ceos/fastmcp
1
0
Fork 0
mirror of https://github.com/PrefectHQ/fastmcp.git synced 2026-08-09 07:09:11 +02:00
Code Issues Projects Releases Packages Wiki Activity

Require exact consent cookie domain

Browse source
This commit is contained in:
Jeremiah Lowin 2026-08-04 17:32:02 -04:00
commit ce58ceec7b
No known key found for this signature in database
14 changed files with 121 additions and 93 deletions
Download patch file Download diff file Expand all files Collapse all files

12
docs/servers/auth/oauth-proxy.mdx
View file

@ -342,23 +342,23 @@ auth = OAuthProxy(..., client_storage=MemoryStore())
</Warning>
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Controls the browser-enforced scope of the signed cookies used by FastMCP's consent flow.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Sets an explicit domain for the signed cookies used by FastMCP's consent flow. By default, FastMCP uses `__Host-` cookies on HTTPS, which browsers restrict to the exact host.
- `"host-only"` (default) uses the `__Host-` prefix on HTTPS. This is the strongest policy because browsers reject a `Domain` attribute and prevent sibling subdomains from setting the cookie.
- `"domain-compatible"` uses the `__Secure-` prefix on HTTPS. Use this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. Cookie signing, `Secure`, `HttpOnly`, and `SameSite=Lax` remain enabled, but browser-enforced host isolation is lost.
Set this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. The value must exactly match the hostname in `base_url`; FastMCP rejects parent domains. Configuring it uses `__Secure-` cookies and preserves signing, `Secure`, `HttpOnly`, and `SameSite=Lax`.
```python
from fastmcp.server.auth.providers.azure import AzureProvider
auth = AzureProvider(
...,
consent_cookie_policy="domain-compatible",
base_url="https://my-app.azurewebsites.net",
consent_cookie_domain="my-app.azurewebsites.net",
)
```
<Warning>
Prefer the default `"host-only"` policy. The compatibility policy allows consent cookies to be scoped to sibling subdomains and should only be enabled when the deployment platform makes `__Host-` cookies unusable.
Prefer the host-only default. A domain cookie is also sent to child subdomains, so only enable this when those hosts are trusted and the deployment platform makes `__Host-` cookies unusable.
</Warning>
</ParamField>

4
docs/servers/auth/oidc-proxy.mdx
View file

@ -209,8 +209,8 @@ auth = OIDCProxy(
Consent screen behavior for authorization requests. Accepts `True` (default; always prompt — strongest protection), `"remember"` (silent consent on return visits via signed cookie, gated by `Sec-Fetch-Site` to block AS-in-the-middle attacks), `"external"` (same authorization path as `False`, but the warning is suppressed because the operator asserts that equivalent protections are enforced externally), or `False` (disable entirely; local/testing only). See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for full details on each mode and the security trade-offs.
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Consent cookie scope policy. The default `"host-only"` uses `__Host-` cookies on HTTPS. `"domain-compatible"` uses `__Secure-` cookies for hosting layers that add a `Domain` attribute, weakening browser-enforced host isolation while retaining signed, `Secure`, `HttpOnly`, `SameSite=Lax` cookies. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Explicit domain for consent cookies. By default, FastMCP uses host-only `__Host-` cookies on HTTPS. Set this only for hosting layers that add a `Domain` attribute; the value must exactly match the hostname in `base_url`. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
</ParamField>
<ParamField body="consent_csp_policy" type="str | None" default="None">

12
docs/v2/servers/auth/oauth-proxy.mdx
View file

@ -323,23 +323,23 @@ auth = OAuthProxy(..., client_storage=MemoryStore())
</Warning>
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Controls the browser-enforced scope of the signed cookies used by FastMCP's consent flow.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Sets an explicit domain for the signed cookies used by FastMCP's consent flow. By default, FastMCP uses `__Host-` cookies on HTTPS, which browsers restrict to the exact host.
- `"host-only"` (default) uses the `__Host-` prefix on HTTPS. This is the strongest policy because browsers reject a `Domain` attribute and prevent sibling subdomains from setting the cookie.
- `"domain-compatible"` uses the `__Secure-` prefix on HTTPS. Use this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. Cookie signing, `Secure`, `HttpOnly`, and `SameSite=Lax` remain enabled, but browser-enforced host isolation is lost.
Set this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. The value must exactly match the hostname in `base_url`; FastMCP rejects parent domains. Configuring it uses `__Secure-` cookies and preserves signing, `Secure`, `HttpOnly`, and `SameSite=Lax`.
```python
from fastmcp.server.auth.providers.azure import AzureProvider
auth = AzureProvider(
...,
consent_cookie_policy="domain-compatible",
base_url="https://my-app.azurewebsites.net",
consent_cookie_domain="my-app.azurewebsites.net",
)
```
<Warning>
Prefer the default `"host-only"` policy. The compatibility policy allows consent cookies to be scoped to sibling subdomains and should only be enabled when the deployment platform makes `__Host-` cookies unusable.
Prefer the host-only default. A domain cookie is also sent to child subdomains, so only enable this when those hosts are trusted and the deployment platform makes `__Host-` cookies unusable.
</Warning>
</ParamField>

4
docs/v2/servers/auth/oidc-proxy.mdx
View file

@ -202,8 +202,8 @@ auth = OIDCProxy(
Consent screen behavior for authorization requests. Accepts `True` (default; always prompt — strongest protection), `"remember"` (silent consent on return visits via signed cookie, gated by `Sec-Fetch-Site` to block AS-in-the-middle attacks), `"external"` (same authorization path as `False`, but the warning is suppressed because the operator asserts that equivalent protections are enforced externally), or `False` (disable entirely; local/testing only). See the [OAuthProxy documentation](/v2/servers/auth/oauth-proxy) for full details on each mode and the security trade-offs.
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Consent cookie scope policy. The default `"host-only"` uses `__Host-` cookies on HTTPS. `"domain-compatible"` uses `__Secure-` cookies for hosting layers that add a `Domain` attribute, weakening browser-enforced host isolation while retaining signed, `Secure`, `HttpOnly`, `SameSite=Lax` cookies. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Explicit domain for consent cookies. By default, FastMCP uses host-only `__Host-` cookies on HTTPS. Set this only for hosting layers that add a `Domain` attribute; the value must exactly match the hostname in `base_url`. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
</ParamField>
<ParamField body="consent_csp_policy" type="str | None" default="None">

12
docs/v3/servers/auth/oauth-proxy.mdx
View file

@ -337,23 +337,23 @@ auth = OAuthProxy(..., client_storage=MemoryStore())
</Warning>
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Controls the browser-enforced scope of the signed cookies used by FastMCP's consent flow.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Sets an explicit domain for the signed cookies used by FastMCP's consent flow. By default, FastMCP uses `__Host-` cookies on HTTPS, which browsers restrict to the exact host.
- `"host-only"` (default) uses the `__Host-` prefix on HTTPS. This is the strongest policy because browsers reject a `Domain` attribute and prevent sibling subdomains from setting the cookie.
- `"domain-compatible"` uses the `__Secure-` prefix on HTTPS. Use this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. Cookie signing, `Secure`, `HttpOnly`, and `SameSite=Lax` remain enabled, but browser-enforced host isolation is lost.
Set this only when a hosting layer, such as Azure Functions, adds a `Domain` attribute to response cookies. The value must exactly match the hostname in `base_url`; FastMCP rejects parent domains. Configuring it uses `__Secure-` cookies and preserves signing, `Secure`, `HttpOnly`, and `SameSite=Lax`.
```python
from fastmcp.server.auth.providers.azure import AzureProvider
auth = AzureProvider(
...,
consent_cookie_policy="domain-compatible",
base_url="https://my-app.azurewebsites.net",
consent_cookie_domain="my-app.azurewebsites.net",
)
```
<Warning>
Prefer the default `"host-only"` policy. The compatibility policy allows consent cookies to be scoped to sibling subdomains and should only be enabled when the deployment platform makes `__Host-` cookies unusable.
Prefer the host-only default. A domain cookie is also sent to child subdomains, so only enable this when those hosts are trusted and the deployment platform makes `__Host-` cookies unusable.
</Warning>
</ParamField>

4
docs/v3/servers/auth/oidc-proxy.mdx
View file

@ -202,8 +202,8 @@ auth = OIDCProxy(
Consent screen behavior for authorization requests. Accepts `True` (default; always prompt — strongest protection), `"remember"` (silent consent on return visits via signed cookie, gated by `Sec-Fetch-Site` to block AS-in-the-middle attacks), `"external"` (same authorization path as `False`, but the warning is suppressed because the operator asserts that equivalent protections are enforced externally), or `False` (disable entirely; local/testing only). See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for full details on each mode and the security trade-offs.
</ParamField>
<ParamField body="consent_cookie_policy" type='Literal["host-only", "domain-compatible"]' default='"host-only"'>
Consent cookie scope policy. The default `"host-only"` uses `__Host-` cookies on HTTPS. `"domain-compatible"` uses `__Secure-` cookies for hosting layers that add a `Domain` attribute, weakening browser-enforced host isolation while retaining signed, `Secure`, `HttpOnly`, `SameSite=Lax` cookies. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
<ParamField body="consent_cookie_domain" type="str | None" default="None">
Explicit domain for consent cookies. By default, FastMCP uses host-only `__Host-` cookies on HTTPS. Set this only for hosting layers that add a `Domain` attribute; the value must exactly match the hostname in `base_url`. See the [OAuthProxy documentation](/servers/auth/oauth-proxy) for the security trade-off.
</ParamField>
<ParamField body="consent_csp_policy" type="str | None" default="None">

3
fastmcp_slim/fastmcp/server/auth/oauth_proxy/__init__.py
View file

@ -7,9 +7,8 @@ This package provides OAuth proxy functionality split across multiple modules:
- proxy: Main OAuthProxy class
"""
from fastmcp.server.auth.oauth_proxy.proxy import ConsentCookiePolicy, OAuthProxy
from fastmcp.server.auth.oauth_proxy.proxy import OAuthProxy
__all__ = [
"ConsentCookiePolicy",
"OAuthProxy",
]

5
fastmcp_slim/fastmcp/server/auth/oauth_proxy/consent.py
View file

@ -76,7 +76,7 @@ class ConsentMixin:
def _cookie_name(self: OAuthProxy, base_name: str) -> str:
"""Return secure cookie name for HTTPS, fallback for HTTP development."""
if self._is_https:
if self._consent_cookie_policy == "domain-compatible":
if self._consent_cookie_domain is not None:
return f"__Secure-{base_name}"
return f"__Host-{base_name}"
return f"__{base_name}"
@ -178,6 +178,7 @@ class ConsentMixin:
httponly=True,
samesite="lax",
path="/",
domain=self._consent_cookie_domain,
)
def _read_consent_bindings(self: OAuthProxy, request: Request) -> dict[str, str]:
@ -220,6 +221,7 @@ class ConsentMixin:
httponly=True,
samesite="lax",
path="/",
domain=self._consent_cookie_domain,
)
return
payload_bytes = json.dumps(bindings, separators=(",", ":")).encode()
@ -233,6 +235,7 @@ class ConsentMixin:
httponly=True,
samesite="lax",
path="/",
domain=self._consent_cookie_domain,
)
def _set_consent_binding_cookie(

46
fastmcp_slim/fastmcp/server/auth/oauth_proxy/proxy.py
View file

@ -119,8 +119,6 @@ from fastmcp.utilities.logging import get_logger
logger = get_logger(__name__)
ConsentCookiePolicy = Literal["host-only", "domain-compatible"]
_REFRESH_LOCK_CACHE_SIZE = 10_000
#: SEP-837: the client's declared `application_type`, recovered from the raw DCR
@ -334,7 +332,7 @@ class OAuthProxy(OAuthProvider, ConsentMixin):
jwt_signing_key: str | bytes | None = None,
# Consent screen configuration
require_authorization_consent: bool | Literal["remember", "external"] = True,
consent_cookie_policy: ConsentCookiePolicy = "host-only",
consent_cookie_domain: str | None = None,
consent_csp_policy: str | None = None,
# Token expiry fallback
fallback_access_token_expiry_seconds: int | None = None,
@ -406,13 +404,14 @@ class OAuthProxy(OAuthProvider, ConsentMixin):
FastMCP does not provide or verify those external protections.
- False: skip consent entirely. SECURITY WARNING: only set to
False for local development or testing environments.
consent_cookie_policy: Cookie scope policy for the consent flow.
``"host-only"`` (default) uses ``__Host-`` cookies on HTTPS,
which browsers reject if a hosting layer adds a ``Domain``
attribute. ``"domain-compatible"`` uses ``__Secure-`` cookies
instead so those rewrites remain valid, at the cost of allowing
the cookies to be scoped to sibling subdomains. Cookie signing,
``Secure``, ``HttpOnly``, and ``SameSite=Lax`` remain enabled.
consent_cookie_domain: Explicit domain for consent cookies. By default,
FastMCP uses host-only ``__Host-`` cookies on HTTPS. Set this only
when a hosting layer adds a ``Domain`` attribute to response cookies.
The value must exactly match the hostname in ``base_url``; parent
domains are rejected. Configuring a domain uses ``__Secure-`` cookies
and allows them to reach child subdomains, weakening browser-enforced
host isolation. Cookie signing, ``Secure``, ``HttpOnly``, and
``SameSite=Lax`` remain enabled.
consent_csp_policy: Content Security Policy for the consent page.
If None (default), uses the built-in CSP policy with appropriate directives.
If empty string "", disables CSP entirely (no meta tag is rendered).
@ -527,17 +526,26 @@ class OAuthProxy(OAuthProvider, ConsentMixin):
self._require_authorization_consent: bool | Literal["remember", "external"] = (
require_authorization_consent
)
if consent_cookie_policy not in ("host-only", "domain-compatible"):
raise ValueError(
"consent_cookie_policy must be 'host-only' or 'domain-compatible'"
)
self._consent_cookie_policy: ConsentCookiePolicy = consent_cookie_policy
self._consent_cookie_domain: str | None = None
if consent_cookie_domain is not None:
assert self.base_url is not None
assert self.base_url.host is not None
configured_domain = consent_cookie_domain.lower().rstrip(".")
base_host = self.base_url.host.lower().rstrip(".")
if configured_domain != base_host:
raise ValueError(
"consent_cookie_domain must exactly match the hostname in base_url"
)
if self.base_url.scheme != "https":
raise ValueError("consent_cookie_domain requires an HTTPS base_url")
self._consent_cookie_domain = configured_domain
self._consent_csp_policy: str | None = consent_csp_policy
if consent_cookie_policy == "domain-compatible":
if self._consent_cookie_domain is not None:
logger.warning(
"Domain-compatible consent cookies use __Secure- instead of "
"__Host-; this permits Domain rewrites but weakens browser-enforced "
"host isolation."
"Consent cookies are scoped to %s and use __Secure- instead of "
"__Host-. Child subdomains can receive or replace these cookies; "
"only use this setting when those hosts are trusted.",
self._consent_cookie_domain,
)
if require_authorization_consent == "external":
logger.info(

16
fastmcp_slim/fastmcp/server/auth/oidc_proxy.py
View file

@ -19,7 +19,7 @@ from typing_extensions import Self
from fastmcp.server.auth import TokenVerifier
from fastmcp.server.auth.identity_assertion import IdentityAssertion
from fastmcp.server.auth.oauth_proxy import ConsentCookiePolicy, OAuthProxy
from fastmcp.server.auth.oauth_proxy import OAuthProxy
from fastmcp.server.auth.oauth_proxy.models import UpstreamTokenSet
from fastmcp.server.auth.providers.jwt import JWTVerifier
from fastmcp.utilities.logging import get_logger
@ -234,7 +234,7 @@ class OIDCProxy(OAuthProxy):
token_endpoint_auth_method: str | None = None,
# Consent screen configuration
require_authorization_consent: bool | Literal["remember", "external"] = True,
consent_cookie_policy: ConsentCookiePolicy = "host-only",
consent_cookie_domain: str | None = None,
consent_csp_policy: str | None = None,
forward_resource: bool = True,
# Extra parameters
@ -311,11 +311,11 @@ class OIDCProxy(OAuthProxy):
but the warning is suppressed as an operator acknowledgment that
equivalent protections are enforced externally.
SECURITY WARNING: Only set to False for local development or testing environments.
consent_cookie_policy: Cookie scope policy for the consent flow.
``"host-only"`` (default) uses ``__Host-`` cookies on HTTPS.
``"domain-compatible"`` uses ``__Secure-`` cookies for hosting
layers that add a ``Domain`` attribute, weakening browser-enforced
host isolation while retaining signed, secure cookies.
consent_cookie_domain: Explicit domain for consent cookies. By default,
FastMCP uses host-only ``__Host-`` cookies on HTTPS. Set this only
for hosting layers that add a ``Domain`` attribute. The value must
exactly match the hostname in ``base_url`` and causes ``__Secure-``
cookies to be used, allowing child subdomains to receive them.
consent_csp_policy: Content Security Policy for the consent page.
If None (default), uses the built-in CSP policy with appropriate directives.
If empty string "", disables CSP entirely (no meta tag is rendered).
@ -436,7 +436,7 @@ class OIDCProxy(OAuthProxy):
"jwt_signing_key": jwt_signing_key,
"token_endpoint_auth_method": token_endpoint_auth_method,
"require_authorization_consent": require_authorization_consent,
"consent_cookie_policy": consent_cookie_policy,
"consent_cookie_domain": consent_cookie_domain,
"consent_csp_policy": consent_csp_policy,
"forward_resource": forward_resource,
"fallback_access_token_expiry_seconds": fallback_access_token_expiry_seconds,

18
fastmcp_slim/fastmcp/server/auth/providers/azure.py
View file

@ -15,7 +15,7 @@ from key_value.aio.protocols import AsyncKeyValue
from fastmcp.dependencies import Dependency
from fastmcp.server.auth.auth import MultiAuth
from fastmcp.server.auth.oauth_proxy import ConsentCookiePolicy, OAuthProxy
from fastmcp.server.auth.oauth_proxy import OAuthProxy
from fastmcp.server.auth.providers.jwt import JWTVerifier
from fastmcp.utilities.auth import decode_jwt_payload, parse_scopes
from fastmcp.utilities.logging import get_logger
@ -113,7 +113,7 @@ class AzureProvider(OAuthProxy):
client_storage: AsyncKeyValue | None = None,
jwt_signing_key: str | bytes | None = None,
require_authorization_consent: bool | Literal["remember", "external"] = True,
consent_cookie_policy: ConsentCookiePolicy = "host-only",
consent_cookie_domain: str | None = None,
consent_csp_policy: str | None = None,
forward_resource: bool = True,
fallback_refresh_token_expiry_seconds: int | None = None,
@ -178,12 +178,12 @@ class AzureProvider(OAuthProxy):
but the warning is suppressed as an operator acknowledgment that
equivalent protections are enforced externally.
SECURITY WARNING: Only set to False for local development or testing environments.
consent_cookie_policy: Cookie scope policy for the consent flow.
``"host-only"`` (default) uses ``__Host-`` cookies on HTTPS.
``"domain-compatible"`` uses ``__Secure-`` cookies for hosting
layers such as Azure Functions that add a ``Domain`` attribute,
weakening browser-enforced host isolation while retaining signed,
secure cookies.
consent_cookie_domain: Explicit domain for consent cookies. By default,
FastMCP uses host-only ``__Host-`` cookies on HTTPS. Set this only
for hosting layers such as Azure Functions that add a ``Domain``
attribute. The value must exactly match the hostname in ``base_url``
and causes ``__Secure-`` cookies to be used, allowing child
subdomains to receive them.
http_client: Optional httpx2.AsyncClient for connection pooling in JWKS fetches.
When provided, the client is reused for JWT key fetches and the caller
is responsible for its lifecycle. When None (default), a fresh client is created per fetch.
@ -280,7 +280,7 @@ class AzureProvider(OAuthProxy):
client_storage=client_storage,
jwt_signing_key=jwt_signing_key,
require_authorization_consent=require_authorization_consent,
consent_cookie_policy=consent_cookie_policy,
consent_cookie_domain=consent_cookie_domain,
consent_csp_policy=consent_csp_policy,
forward_resource=forward_resource,
fallback_refresh_token_expiry_seconds=fallback_refresh_token_expiry_seconds,

5
tests/server/auth/providers/test_azure.py
View file

@ -66,7 +66,7 @@ class TestAzureProvider:
assert provider._redirect_path == "/auth/callback"
# Azure provider defaults are set but we can't easily verify them without accessing internals
def test_domain_compatible_consent_cookies(self, memory_storage: MemoryStore):
def test_explicit_consent_cookie_domain(self, memory_storage: MemoryStore):
provider = AzureProvider(
client_id="test_client",
client_secret="test_secret",
@ -75,12 +75,13 @@ class TestAzureProvider:
required_scopes=["read"],
jwt_signing_key="test-secret",
client_storage=memory_storage,
consent_cookie_policy="domain-compatible",
consent_cookie_domain="myserver.com",
)
assert (
provider._cookie_name("MCP_CONSENT_STATE") == "__Secure-MCP_CONSENT_STATE"
)
assert provider._consent_cookie_domain == "myserver.com"
def test_offline_access_automatically_included(self, memory_storage: MemoryStore):
"""Test that offline_access is automatically added to get refresh tokens."""

68
tests/server/auth/test_oauth_consent_page.py
View file

@ -65,8 +65,8 @@ def oauth_proxy_https_remember():
@pytest.fixture
def oauth_proxy_https_domain_compatible():
"""OAuthProxy using __Secure- cookies for platforms that add Domain."""
def oauth_proxy_https_with_cookie_domain():
"""OAuthProxy using an explicit cookie domain for platform compatibility."""
return OAuthProxy(
upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
upstream_token_endpoint="https://github.com/login/oauth/access_token",
@ -76,7 +76,7 @@ def oauth_proxy_https_domain_compatible():
base_url="https://myserver.example",
client_storage=MemoryStore(),
jwt_signing_key="test-secret",
consent_cookie_policy="domain-compatible",
consent_cookie_domain="myserver.example",
)
@ -116,11 +116,11 @@ def _extract_csrf(html: str) -> str | None:
return m.group(1) if m else None
class TestConsentCookiePolicy:
def test_invalid_policy_is_rejected(self):
class TestConsentCookieDomain:
def test_parent_domain_is_rejected(self):
with pytest.raises(
ValueError,
match="consent_cookie_policy must be 'host-only' or 'domain-compatible'",
match="consent_cookie_domain must exactly match the hostname in base_url",
):
OAuthProxy(
upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
@ -131,20 +131,36 @@ class TestConsentCookiePolicy:
base_url="https://myserver.example",
client_storage=MemoryStore(),
jwt_signing_key="test-secret",
consent_cookie_policy="invalid", # ty: ignore[invalid-argument-type]
consent_cookie_domain="example",
)
async def test_domain_compatible_policy_completes_consent_with_secure_cookies(
self, oauth_proxy_https_domain_compatible
def test_domain_requires_https(self):
with pytest.raises(
ValueError, match="consent_cookie_domain requires an HTTPS base_url"
):
OAuthProxy(
upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
upstream_token_endpoint="https://github.com/login/oauth/access_token",
upstream_client_id="client-id",
upstream_client_secret="client-secret",
token_verifier=_Verifier(),
base_url="http://myserver.example",
client_storage=MemoryStore(),
jwt_signing_key="test-secret",
consent_cookie_domain="myserver.example",
)
async def test_explicit_domain_completes_consent_with_secure_cookies(
self, oauth_proxy_https_with_cookie_domain
):
txn_id, _ = await _start_flow(
oauth_proxy_https_domain_compatible,
"domain-compatible-client",
oauth_proxy_https_with_cookie_domain,
"explicit-domain-client",
"http://localhost:6000/callback",
)
app = Starlette(routes=oauth_proxy_https_domain_compatible.get_routes())
app = Starlette(routes=oauth_proxy_https_with_cookie_domain.get_routes())
with TestClient(app) as client:
with TestClient(app, base_url="https://myserver.example") as client:
consent = client.get(f"/consent?txn_id={txn_id}")
csrf = _extract_csrf(consent.text)
assert csrf
@ -154,9 +170,8 @@ class TestConsentCookiePolicy:
assert "Secure" in set_cookie
assert "HttpOnly" in set_cookie
assert "SameSite=lax" in set_cookie
assert "Domain=myserver.example" in set_cookie
for key, value in consent.cookies.items():
client.cookies.set(key, value)
response = client.post(
"/consent",
data={
@ -168,25 +183,27 @@ class TestConsentCookiePolicy:
)
assert response.status_code in (302, 303)
assert "__Secure-MCP_CONSENT_BINDING=" in response.headers.get("set-cookie", "")
binding_cookie = response.headers.get("set-cookie", "")
assert "__Secure-MCP_CONSENT_BINDING=" in binding_cookie
assert "Domain=myserver.example" in binding_cookie
async def test_domain_compatible_policy_does_not_accept_host_prefix(
self, oauth_proxy_https_domain_compatible
async def test_explicit_domain_does_not_accept_host_prefix(
self, oauth_proxy_https_with_cookie_domain
):
txn_id, _ = await _start_flow(
oauth_proxy_https_domain_compatible,
oauth_proxy_https_with_cookie_domain,
"wrong-prefix-client",
"http://localhost:6001/callback",
)
app = Starlette(routes=oauth_proxy_https_domain_compatible.get_routes())
app = Starlette(routes=oauth_proxy_https_with_cookie_domain.get_routes())
with TestClient(app) as browser:
with TestClient(app, base_url="https://myserver.example") as browser:
consent = browser.get(f"/consent?txn_id={txn_id}")
csrf = _extract_csrf(consent.text)
assert csrf
signed_state = consent.cookies["__Secure-MCP_CONSENT_STATE"]
with TestClient(app) as browser:
with TestClient(app, base_url="https://myserver.example") as browser:
browser.cookies.set("__Host-MCP_CONSENT_STATE", signed_state)
response = browser.post(
"/consent",
@ -200,9 +217,7 @@ class TestConsentCookiePolicy:
assert response.status_code == 403
async def test_default_policy_does_not_accept_secure_prefix(
self, oauth_proxy_https
):
async def test_default_does_not_accept_secure_prefix(self, oauth_proxy_https):
txn_id, _ = await _start_flow(
oauth_proxy_https,
"default-policy-client",
@ -230,11 +245,12 @@ class TestConsentCookiePolicy:
assert response.status_code == 403
def test_default_policy_remains_host_only(self, oauth_proxy_https):
def test_default_remains_host_only(self, oauth_proxy_https):
assert (
oauth_proxy_https._cookie_name("MCP_CONSENT_STATE")
== "__Host-MCP_CONSENT_STATE"
)
assert oauth_proxy_https._consent_cookie_domain is None
class TestConsentPageServerIcon:

5
tests/server/auth/test_oidc_proxy.py
View file

@ -489,7 +489,7 @@ class TestOIDCProxyInitialization:
call_args = mock_get.call_args
assert call_args[1]["timeout_seconds"] == 12
def test_domain_compatible_consent_cookies(self, valid_oidc_configuration_dict):
def test_explicit_consent_cookie_domain(self, valid_oidc_configuration_dict):
with patch(
"fastmcp.server.auth.oidc_proxy.OIDCConfiguration.get_oidc_configuration"
) as mock_get:
@ -504,13 +504,14 @@ class TestOIDCProxyInitialization:
client_secret=TEST_CLIENT_SECRET,
base_url=TEST_BASE_URL,
jwt_signing_key="test-secret",
consent_cookie_policy="domain-compatible",
consent_cookie_domain="example.com",
)
validate_proxy(mock_get, proxy, oidc_config)
assert (
proxy._cookie_name("MCP_CONSENT_STATE") == "__Secure-MCP_CONSENT_STATE"
)
assert proxy._consent_cookie_domain == "example.com"
def test_token_verifier_initialization(self, valid_oidc_configuration_dict):
"""Test token verifier initialization."""