Prevent confused deputy attacks in OAuth proxy (#2056)

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Jeremiah Lowin 2025-10-11 10:53:54 -04:00 committed by GitHub
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@ -10,9 +10,9 @@ import { VersionBadge } from "/snippets/version-badge.mdx";
<VersionBadge version="2.12.0" />
OAuth Proxy enables FastMCP servers to authenticate with OAuth providers that **don't support Dynamic Client Registration (DCR)**. This includes virtually all traditional OAuth providers: GitHub, Google, Azure, AWS, Discord, Facebook, and most enterprise identity systems. For providers that do support DCR (like Descope and WorkOS AuthKit), use [`RemoteAuthProvider`](/servers/auth/remote-oauth) instead.
The OAuth proxy enables FastMCP servers to authenticate with OAuth providers that **don't support Dynamic Client Registration (DCR)**. This includes virtually all traditional OAuth providers: GitHub, Google, Azure, AWS, Discord, Facebook, and most enterprise identity systems. For providers that do support DCR (like Descope and WorkOS AuthKit), use [`RemoteAuthProvider`](/servers/auth/remote-oauth) instead.
MCP clients expect to register automatically and obtain credentials on the fly, but traditional providers require manual app registration through their developer consoles. OAuth Proxy bridges this gap by presenting a DCR-compliant interface to MCP clients while using your pre-registered credentials with the upstream provider. When a client attempts to register, the proxy returns your fixed credentials. When a client initiates authorization, the proxy handles the complexity of callback forwarding—storing the client's dynamic callback URL, using its own fixed callback with the provider, then forwarding back to the client after token exchange.
MCP clients expect to register automatically and obtain credentials on the fly, but traditional providers require manual app registration through their developer consoles. The OAuth proxy bridges this gap by presenting a DCR-compliant interface to MCP clients while using your pre-registered credentials with the upstream provider. When a client attempts to register, the proxy returns your fixed credentials. When a client initiates authorization, the proxy handles the complexity of callback forwarding—storing the client's dynamic callback URL, using its own fixed callback with the provider, then forwarding back to the client after token exchange.
This approach enables any MCP client (whether using random localhost ports or fixed URLs like Claude.ai) to authenticate with any traditional OAuth provider, all while maintaining full OAuth 2.1 and PKCE security.
@ -20,7 +20,7 @@ This approach enables any MCP client (whether using random localhost ports or fi
For providers that support OIDC discovery (Auth0, Google with OIDC
configuration, Azure AD), consider using [`OIDC
Proxy`](/servers/auth/oidc-proxy) for automatic configuration. OIDC Proxy
extends OAuth Proxy to automatically discover endpoints from the provider's
extends the OAuth proxy to automatically discover endpoints from the provider's
`/.well-known/openid-configuration` URL, simplifying setup.
</Note>
@ -28,7 +28,7 @@ This approach enables any MCP client (whether using random localhost ports or fi
### Provider Setup Requirements
Before using OAuth Proxy, you need to register your application with your OAuth provider:
Before using the OAuth proxy, you need to register your application with your OAuth provider:
1. **Register your application** in the provider's developer console (GitHub Settings, Google Cloud Console, Azure Portal, etc.)
2. **Configure the redirect URI** as your FastMCP server URL plus your chosen callback path:
@ -41,12 +41,12 @@ Before using OAuth Proxy, you need to register your application with your OAuth
<Warning>
The redirect URI you configure with your provider must exactly match your
FastMCP server's URL plus the callback path. If you customize `redirect_path`
in OAuth Proxy, update your provider's redirect URI accordingly.
in the OAuth proxy, update your provider's redirect URI accordingly.
</Warning>
### Basic Setup
Here's how to implement OAuth Proxy with any provider:
Here's how to implement the OAuth proxy with any provider:
```python
from fastmcp import FastMCP
@ -203,48 +203,6 @@ auth = OAuthProxy(..., client_storage=InMemoryStorage())
</ParamField>
</Card>
### Provider-Specific Parameters
Some OAuth providers require additional parameters beyond the standard OAuth2 flow. Use `extra_authorize_params` and `extra_token_params` to handle these requirements:
#### Auth0 Example
Auth0 requires an `audience` parameter to issue JWT tokens instead of opaque tokens:
```python
auth = OAuthProxy(
upstream_authorization_endpoint="https://your-domain.auth0.com/authorize",
upstream_token_endpoint="https://your-domain.auth0.com/oauth/token",
upstream_client_id="your-auth0-client-id",
upstream_client_secret="your-auth0-client-secret",
# Auth0 requires audience for JWT tokens
extra_authorize_params={
"audience": "https://your-api-identifier.com"
},
extra_token_params={
"audience": "https://your-api-identifier.com"
},
token_verifier=JWTVerifier(
jwks_uri="https://your-domain.auth0.com/.well-known/jwks.json",
issuer="https://your-domain.auth0.com/",
audience="https://your-api-identifier.com"
),
base_url="https://your-server.com"
)
```
#### RFC 8707 Resource Indicators
MCP clients can specify target resources using the standard `resource` parameter (RFC 8707). This is automatically forwarded when present:
```python
# Client code (automatic - no server configuration needed)
# The resource parameter is passed through from AuthorizationParams
```
### Using Built-in Providers
FastMCP includes pre-configured providers for common services:
@ -263,21 +221,57 @@ mcp = FastMCP(name="My Server", auth=auth)
Available providers include `GitHubProvider`, `GoogleProvider`, and others. These handle token verification automatically.
### Token Verification
The OAuth proxy requires a compatible `TokenVerifier` to validate tokens from your provider. Different providers use different token formats:
- **JWT tokens** (Google, Azure): Use `JWTVerifier` with the provider's JWKS endpoint
- **Opaque tokens** (GitHub, Discord): Use provider-specific verifiers or implement custom validation
See the [Token Verification guide](/servers/auth/token-verification) for detailed setup instructions for your provider.
### Scope Configuration
OAuth scopes are configured through your `TokenVerifier`. Set `required_scopes` to automatically request the permissions your application needs:
OAuth scopes control what permissions your application requests from users. They're configured through your `TokenVerifier` (required for the OAuth proxy to validate tokens from your provider). Set `required_scopes` to automatically request the permissions your application needs:
```python
JWTVerifier(..., required_scopes = ["read:user", "write:data"])
```
Dynamic clients created by the proxy will automatically include these scopes in their authorization requests.
Dynamic clients created by the proxy will automatically include these scopes in their authorization requests. See the [Token Verification](#token-verification) section below for detailed setup.
## How It Works
### Custom Parameters
Some OAuth providers require additional parameters beyond the standard OAuth2 flow. Use `extra_authorize_params` and `extra_token_params` to pass provider-specific requirements. For example, Auth0 requires an `audience` parameter to issue JWT tokens instead of opaque tokens:
```python
auth = OAuthProxy(
upstream_authorization_endpoint="https://your-domain.auth0.com/authorize",
upstream_token_endpoint="https://your-domain.auth0.com/oauth/token",
upstream_client_id="your-auth0-client-id",
upstream_client_secret="your-auth0-client-secret",
# Auth0-specific audience parameter
extra_authorize_params={"audience": "https://your-api-identifier.com"},
extra_token_params={"audience": "https://your-api-identifier.com"},
token_verifier=JWTVerifier(
jwks_uri="https://your-domain.auth0.com/.well-known/jwks.json",
issuer="https://your-domain.auth0.com/",
audience="https://your-api-identifier.com"
),
base_url="https://your-server.com"
)
```
The proxy also automatically forwards RFC 8707 `resource` parameters from MCP clients to upstream providers that support them.
## OAuth Flow
```mermaid
sequenceDiagram
participant Client as MCP Client<br/>(localhost:random)
participant User as User
participant Proxy as FastMCP OAuth Proxy<br/>(server:8000)
participant Provider as OAuth Provider<br/>(GitHub, etc.)
@ -285,25 +279,27 @@ sequenceDiagram
Client->>Proxy: 1. POST /register<br/>redirect_uri: localhost:54321/callback
Proxy-->>Client: 2. Returns fixed upstream credentials
Note over Client, Proxy: Authorization with PKCE & Callback Forwarding
Note over Client, User: Authorization with User Consent
Client->>Proxy: 3. GET /authorize<br/>redirect_uri=localhost:54321/callback<br/>code_challenge=CLIENT_CHALLENGE
Note over Proxy: Store transaction with client PKCE<br/>Generate proxy PKCE pair
Proxy->>Provider: 4. Redirect to provider<br/>redirect_uri=server:8000/auth/callback<br/>code_challenge=PROXY_CHALLENGE
Proxy->>User: 4. Show consent page<br/>(client details, redirect URI, scopes)
User->>Proxy: 5. Approve/deny consent
Proxy->>Provider: 6. Redirect to provider<br/>redirect_uri=server:8000/auth/callback<br/>code_challenge=PROXY_CHALLENGE
Note over Provider, Proxy: Provider Callback
Provider->>Proxy: 5. GET /auth/callback<br/>with authorization code
Proxy->>Provider: 6. Exchange code for tokens<br/>code_verifier=PROXY_VERIFIER
Provider-->>Proxy: 7. Access & refresh tokens
Provider->>Proxy: 7. GET /auth/callback<br/>with authorization code
Proxy->>Provider: 8. Exchange code for tokens<br/>code_verifier=PROXY_VERIFIER
Provider-->>Proxy: 9. Access & refresh tokens
Note over Proxy, Client: Client Callback Forwarding
Proxy->>Client: 8. Redirect to localhost:54321/callback<br/>with new authorization code
Proxy->>Client: 10. Redirect to localhost:54321/callback<br/>with new authorization code
Note over Client, Proxy: Token Exchange
Client->>Proxy: 9. POST /token with code<br/>code_verifier=CLIENT_VERIFIER
Proxy-->>Client: 10. Returns stored provider tokens
Client->>Proxy: 11. POST /token with code<br/>code_verifier=CLIENT_VERIFIER
Proxy-->>Client: 12. Returns stored provider tokens
```
The flow diagram above illustrates the complete OAuth Proxy pattern. Let's understand each phase:
The flow diagram above illustrates the complete OAuth proxy pattern. Let's understand each phase:
### Registration Phase
@ -315,9 +311,10 @@ The client initiates OAuth by redirecting to the proxy's `/authorize` endpoint.
1. Stores the client's transaction with its PKCE challenge
2. Generates its own PKCE parameters for upstream security
3. Redirects to the upstream provider using the fixed callback URL
3. Shows the user a consent page with the client's details, redirect URI, and requested scopes
4. If the user approves (or the client was previously approved), redirects to the upstream provider using the fixed callback URL
This dual-PKCE approach maintains end-to-end security at both the client-to-proxy and proxy-to-provider layers.
This dual-PKCE approach maintains end-to-end security at both the client-to-proxy and proxy-to-provider layers. The consent step protects against confused deputy attacks by ensuring you explicitly approve each client before it can complete authorization.
### Callback Phase
@ -336,7 +333,7 @@ This entire flow is transparent to the MCP client—it experiences a standard OA
### PKCE Forwarding
OAuth Proxy automatically handles PKCE (Proof Key for Code Exchange) when working with providers that support or require it. The proxy generates its own PKCE parameters to send upstream while separately validating the client's PKCE, ensuring end-to-end security at both layers.
The OAuth proxy automatically handles PKCE (Proof Key for Code Exchange) when working with providers that support or require it. The proxy generates its own PKCE parameters to send upstream while separately validating the client's PKCE, ensuring end-to-end security at both layers.
This is enabled by default via the `forward_pkce` parameter and works seamlessly with providers like Google, Azure AD, and GitHub. Only disable it for legacy providers that don't support PKCE:
@ -350,7 +347,7 @@ auth = OAuthProxy(
### Redirect URI Validation
While OAuth Proxy accepts all redirect URIs by default (for DCR compatibility), you can restrict which clients can connect by specifying allowed patterns:
While the OAuth proxy accepts all redirect URIs by default (for DCR compatibility), you can restrict which clients can connect by specifying allowed patterns:
```python
# Allow only localhost clients (common for development)
@ -375,20 +372,29 @@ auth = OAuthProxy(
Check your server logs for "Client registered with redirect_uri" messages to identify what URLs your clients use.
## Token Verification
## Security
OAuth Proxy requires a compatible `TokenVerifier` to validate tokens from your provider. Different providers use different token formats:
### Confused Deputy Attacks
- **JWT tokens** (Google, Azure): Use `JWTVerifier` with the provider's JWKS endpoint
- **Opaque tokens** (GitHub, Discord): Use provider-specific verifiers or implement custom validation
<VersionBadge version="2.13.0" />
See the [Token Verification guide](/servers/auth/token-verification) for detailed setup instructions for your provider.
A confused deputy attack allows a malicious client to steal your authorization by tricking you into granting it access under your identity.
The OAuth proxy works by bridging DCR clients to traditional auth providers, which means that multiple MCP clients connect through a single upstream OAuth application. An attacker can exploit this shared application by registering a malicious client with their own redirect URI, then sending you an authorization link. When you click it, your browser goes through the OAuth flow—but since you may have already authorized this OAuth app before, the provider might auto-approve the request. The authorization code then gets sent to the attacker's redirect URI instead of a legitimate client, giving them access under your credentials.
#### Mitigation
FastMCP's OAuth proxy requires you to explicitly consent whenever any new or unrecognized client attempts to connect to your server. Before any authorization happens, you see a consent page showing the client's details, redirect URI, and requested scopes. This gives you the opportunity to review and deny suspicious requests. Once you approve a client, it's remembered so you don't see the consent page again for that client. The consent mechanism is implemented with CSRF tokens and cryptographically signed cookies to prevent tampering.
**Learn more:**
- [MCP Security Best Practices](https://modelcontextprotocol.io/specification/2025-06-18/basic/security_best_practices#confused-deputy-problem) - Official specification guidance
- [Confused Deputy Attacks Explained](https://den.dev/blog/mcp-confused-deputy-api-management/) - Detailed walkthrough by Den Delimarsky
## Environment Configuration
<VersionBadge version="2.12.1" />
For production deployments, configure OAuth Proxy through environment variables instead of hardcoding credentials:
For production deployments, configure the OAuth proxy through environment variables instead of hardcoding credentials:
```bash
# Specify the provider implementation

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@ -10,15 +10,15 @@ import { VersionBadge } from "/snippets/version-badge.mdx";
<VersionBadge version="2.12.4" />
OIDC Proxy enables FastMCP servers to authenticate with OIDC providers that **don't support Dynamic Client Registration (DCR)** out of the box. This includes OAuth providers like: Auth0, Google, Azure, AWS, etc. For providers that do support DCR (like WorkOS AuthKit), use [`RemoteAuthProvider`](/servers/auth/remote-oauth) instead.
The OIDC proxy enables FastMCP servers to authenticate with OIDC providers that **don't support Dynamic Client Registration (DCR)** out of the box. This includes OAuth providers like: Auth0, Google, Azure, AWS, etc. For providers that do support DCR (like WorkOS AuthKit), use [`RemoteAuthProvider`](/servers/auth/remote-oauth) instead.
The OIDC Proxy is built upon [`OAuthProxy`](/servers/auth/oauth-proxy) so it has all the same functionality under the covers.
The OIDC proxy is built upon [`OAuthProxy`](/servers/auth/oauth-proxy) so it has all the same functionality under the covers.
## Implementation
### Provider Setup Requirements
Before using OIDC Proxy, you need to register your application with your OAuth provider:
Before using the OIDC proxy, you need to register your application with your OAuth provider:
1. **Register your application** in the provider's developer console (Auth0 Applications, Google Cloud Console, Azure Portal, etc.)
2. **Configure the redirect URI** as your FastMCP server URL plus your chosen callback path:
@ -30,12 +30,12 @@ Before using OIDC Proxy, you need to register your application with your OAuth p
<Warning>
The redirect URI you configure with your provider must exactly match your
FastMCP server's URL plus the callback path. If you customize `redirect_path`
in OAuth Proxy, update your provider's redirect URI accordingly.
in the OIDC proxy, update your provider's redirect URI accordingly.
</Warning>
### Basic Setup
Here's how to implement OIDC Proxy with any provider:
Here's how to implement the OIDC proxy with any provider:
```python
from fastmcp import FastMCP
@ -172,7 +172,7 @@ Dynamic clients created by the proxy will automatically include these scopes in
<VersionBadge version="2.13.0" />
For production deployments, configure OIDC Proxy through environment variables instead of hardcoding credentials:
For production deployments, configure the OIDC proxy through environment variables instead of hardcoding credentials:
```bash
# Specify the provider implementation

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@ -12,12 +12,21 @@ from dataclasses import dataclass
from starlette.applications import Starlette
from starlette.requests import Request
from starlette.responses import HTMLResponse
from starlette.routing import Route
from uvicorn import Config, Server
from fastmcp.utilities.http import find_available_port
from fastmcp.utilities.logging import get_logger
from fastmcp.utilities.ui import (
HELPER_TEXT_STYLES,
INFO_BOX_STYLES,
STATUS_MESSAGE_STYLES,
create_info_box,
create_logo,
create_page,
create_secure_html_response,
create_status_message,
)
logger = get_logger(__name__)
@ -29,155 +38,41 @@ def create_callback_html(
server_url: str | None = None,
) -> str:
"""Create a styled HTML response for OAuth callbacks."""
logo_url = "https://gofastmcp.com/assets/brand/blue-logo.png"
# Build the main status message
if is_success:
status_title = "Authentication successful"
status_icon = ""
icon_bg = "#10b98120"
else:
status_title = "Authentication failed"
status_icon = ""
icon_bg = "#ef444420"
status_title = (
"Authentication successful" if is_success else "Authentication failed"
)
# Add detail info box for both success and error cases
detail_info = ""
if is_success and server_url:
detail_info = f"""
<div class="info-box">
Connected to: <strong>{server_url}</strong>
</div>
"""
detail_info = create_info_box(
f"Connected to: <strong>{server_url}</strong>", centered=True
)
elif not is_success:
detail_info = f"""
<div class="info-box error">
{message}
</div>
"""
detail_info = create_info_box(message, is_error=True, centered=True)
return f"""
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>{title}</title>
<style>
* {{
margin: 0;
padding: 0;
box-sizing: border-box;
}}
body {{
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
margin: 0;
padding: 0;
min-height: 100vh;
display: flex;
align-items: center;
justify-content: center;
background: #ffffff;
color: #0a0a0a;
}}
.container {{
background: #ffffff;
border: 1px solid #e5e5e5;
padding: 3rem 2rem;
border-radius: 0.75rem;
box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
text-align: center;
max-width: 28rem;
margin: 1rem;
position: relative;
}}
.logo {{
width: 60px;
height: auto;
margin-bottom: 2rem;
display: block;
margin-left: auto;
margin-right: auto;
}}
.status-message {{
display: flex;
align-items: center;
justify-content: center;
gap: 0.75rem;
margin-bottom: 1.5rem;
}}
.status-icon {{
font-size: 1.5rem;
line-height: 1;
display: inline-flex;
align-items: center;
justify-content: center;
width: 2rem;
height: 2rem;
background: {icon_bg};
border-radius: 0.5rem;
flex-shrink: 0;
}}
.message {{
font-size: 1.125rem;
line-height: 1.75;
color: #0a0a0a;
font-weight: 600;
text-align: left;
}}
.info-box {{
background: #f5f5f5;
border: 1px solid #e5e5e5;
border-radius: 0.5rem;
padding: 0.875rem;
margin: 1.25rem 0;
font-size: 0.875rem;
color: #525252;
font-family: 'SF Mono', 'Monaco', 'Consolas', 'Courier New', monospace;
text-align: left;
}}
.info-box.error {{
background: #fef2f2;
border-color: #fecaca;
color: #991b1b;
}}
.info-box strong {{
color: #0a0a0a;
font-weight: 600;
}}
.close-instruction {{
font-size: 0.875rem;
color: #737373;
margin-top: 1.5rem;
}}
</style>
</head>
<body>
# Build the page content
content = f"""
<div class="container">
<img src="{logo_url}" alt="FastMCP" class="logo" />
<div class="status-message">
<span class="status-icon">{status_icon}</span>
<div class="message">{status_title}</div>
</div>
{create_logo()}
{create_status_message(status_title, is_success=is_success)}
{detail_info}
<div class="close-instruction">
You can safely close this tab now.
</div>
</div>
</body>
</html>
"""
# Additional styles needed for this page
additional_styles = STATUS_MESSAGE_STYLES + INFO_BOX_STYLES + HELPER_TEXT_STYLES
return create_page(
content=content,
title=title,
additional_styles=additional_styles,
)
@dataclass
class CallbackResponse:
@ -221,32 +116,34 @@ def create_oauth_callback_server(
if callback_response.error:
error_desc = callback_response.error_description or "Unknown error"
# Create user-friendly error messages
if callback_response.error == "access_denied":
user_message = "Access was denied by the authorization server."
else:
user_message = f"Authorization failed: {error_desc}"
# Resolve future with exception if provided
if response_future and not response_future.done():
response_future.set_exception(
RuntimeError(
f"OAuth error: {callback_response.error} - {error_desc}"
)
)
response_future.set_exception(RuntimeError(user_message))
return HTMLResponse(
return create_secure_html_response(
create_callback_html(
f"FastMCP OAuth Error: {callback_response.error}<br>{error_desc}",
user_message,
is_success=False,
),
status_code=400,
)
if not callback_response.code:
user_message = "No authorization code was received from the server."
# Resolve future with exception if provided
if response_future and not response_future.done():
response_future.set_exception(
RuntimeError("OAuth callback missing authorization code")
)
response_future.set_exception(RuntimeError(user_message))
return HTMLResponse(
return create_secure_html_response(
create_callback_html(
"FastMCP OAuth Error: No authorization code received",
user_message,
is_success=False,
),
status_code=400,
@ -254,17 +151,17 @@ def create_oauth_callback_server(
# Check for missing state parameter (indicates OAuth flow issue)
if callback_response.state is None:
user_message = (
"The OAuth server did not return the expected state parameter."
)
# Resolve future with exception if provided
if response_future and not response_future.done():
response_future.set_exception(
RuntimeError(
"OAuth server did not return state parameter - authentication failed"
)
)
response_future.set_exception(RuntimeError(user_message))
return HTMLResponse(
return create_secure_html_response(
create_callback_html(
"FastMCP OAuth Error: Authentication failed<br>The OAuth server did not return the expected state parameter",
user_message,
is_success=False,
),
status_code=400,
@ -276,7 +173,7 @@ def create_oauth_callback_server(
(callback_response.code, callback_response.state)
)
return HTMLResponse(
return create_secure_html_response(
create_callback_html("", is_success=True, server_url=server_url)
)

View file

@ -18,12 +18,15 @@ production use with enterprise identity providers.
from __future__ import annotations
import base64
import hashlib
import hmac
import json
import secrets
import time
from base64 import urlsafe_b64encode
from typing import TYPE_CHECKING, Any, Final
from urllib.parse import urlencode
from urllib.parse import urlencode, urlparse
import httpx
from authlib.common.security import generate_token
@ -48,14 +51,26 @@ from mcp.server.auth.settings import (
RevocationOptions,
)
from mcp.shared.auth import OAuthClientInformationFull, OAuthToken
from pydantic import AnyHttpUrl, AnyUrl, Field, SecretStr
from pydantic import AnyHttpUrl, AnyUrl, BaseModel, Field, SecretStr
from starlette.requests import Request
from starlette.responses import RedirectResponse
from starlette.responses import HTMLResponse, RedirectResponse
from starlette.routing import Route
from fastmcp.server.auth.auth import OAuthProvider, TokenVerifier
from fastmcp.server.auth.redirect_validation import validate_redirect_uri
from fastmcp.server.auth.redirect_validation import (
validate_redirect_uri,
)
from fastmcp.utilities.logging import get_logger
from fastmcp.utilities.ui import (
BUTTON_STYLES,
DETAIL_BOX_STYLES,
INFO_BOX_STYLES,
TOOLTIP_STYLES,
create_detail_box,
create_logo,
create_page,
create_secure_html_response,
)
if TYPE_CHECKING:
pass
@ -63,6 +78,62 @@ if TYPE_CHECKING:
logger = get_logger(__name__)
# -------------------------------------------------------------------------
# Constants
# -------------------------------------------------------------------------
# Default token expiration times
DEFAULT_ACCESS_TOKEN_EXPIRY_SECONDS: Final[int] = 60 * 60 # 1 hour
DEFAULT_AUTH_CODE_EXPIRY_SECONDS: Final[int] = 5 * 60 # 5 minutes
# HTTP client timeout
HTTP_TIMEOUT_SECONDS: Final[int] = 30
# -------------------------------------------------------------------------
# Pydantic Models
# -------------------------------------------------------------------------
class OAuthTransaction(BaseModel):
"""OAuth transaction state for consent flow.
Stored server-side to track active authorization flows with client context.
Includes CSRF tokens for consent protection per MCP security best practices.
"""
txn_id: str
client_id: str
client_redirect_uri: str
client_state: str
code_challenge: str | None
code_challenge_method: str
scopes: list[str]
created_at: float
resource: str | None = None
proxy_code_verifier: str | None = None
csrf_token: str | None = None
csrf_expires_at: float | None = None
class ClientCode(BaseModel):
"""Client authorization code with PKCE and upstream tokens.
Stored server-side after upstream IdP callback. Contains the upstream
tokens bound to the client's PKCE challenge for secure token exchange.
"""
code: str
client_id: str
redirect_uri: str
code_challenge: str | None
code_challenge_method: str
scopes: list[str]
idp_tokens: dict[str, Any]
expires_at: float
created_at: float
class ProxyDCRClient(OAuthClientInformationFull):
"""Client for DCR proxy with configurable redirect URI validation.
@ -90,6 +161,7 @@ class ProxyDCRClient(OAuthClientInformationFull):
"""
allowed_redirect_uri_patterns: list[str] | None = Field(default=None)
client_name: str | None = Field(default=None)
def validate_redirect_uri(self, redirect_uri: AnyUrl | None) -> AnyUrl:
"""Validate redirect URI against allowed patterns.
@ -112,12 +184,110 @@ class ProxyDCRClient(OAuthClientInformationFull):
return super().validate_redirect_uri(redirect_uri)
# Default token expiration times
DEFAULT_ACCESS_TOKEN_EXPIRY_SECONDS: Final[int] = 60 * 60 # 1 hour
DEFAULT_AUTH_CODE_EXPIRY_SECONDS: Final[int] = 5 * 60 # 5 minutes
# -------------------------------------------------------------------------
# Helper Functions
# -------------------------------------------------------------------------
# HTTP client timeout
HTTP_TIMEOUT_SECONDS: Final[int] = 30
def create_consent_html(
client_id: str,
redirect_uri: str,
scopes: list[str],
txn_id: str,
csrf_token: str,
client_name: str | None = None,
title: str = "Authorization Consent",
) -> str:
"""Create a styled HTML consent page for OAuth authorization requests."""
# Format scopes for display
scopes_display = ", ".join(scopes) if scopes else "None"
# Build warning box with client name if available
client_display = client_name or client_id
warning_box = f"""
<div class="warning-box">
<p><strong>{client_display} is requesting access to this FastMCP server.</strong></p>
<p>Review the details below before approving.</p>
</div>
"""
# Build detail box with client information
detail_rows = []
if client_name:
detail_rows.append(("Client Name", client_name))
detail_rows.extend(
[
("Client ID", client_id),
("Redirect URI", redirect_uri),
("Requested Scopes", scopes_display),
]
)
detail_box = create_detail_box(detail_rows)
# Build form with buttons
form = f"""
<form id="consentForm" method="POST" action="/consent/submit">
<input type="hidden" name="txn_id" value="{txn_id}" />
<input type="hidden" name="csrf_token" value="{csrf_token}" />
<div class="button-group">
<button type="submit" name="action" value="approve" class="btn-approve">Approve</button>
<button type="submit" name="action" value="deny" class="btn-deny">Deny</button>
</div>
</form>
"""
# Build help link with tooltip
help_link = """
<div class="help-link-container">
<span class="help-link">
Why am I seeing this?
<span class="tooltip">
This FastMCP server requires your consent to allow a new client
to connect. This protects you from <a
href="https://modelcontextprotocol.io/specification/2025-06-18/basic/security_best_practices#confused-deputy-problem"
target="_blank" class="tooltip-link">confused deputy
attacks</a>, where malicious clients could impersonate you
and steal access.<br><br>
<a
href="https://gofastmcp.com/servers/auth/oauth-proxy#confused-deputy-attacks/"
target="_blank" class="tooltip-link">Learn more about
FastMCP security </a>
</span>
</span>
</div>
"""
# Build the page content
content = f"""
<div class="container">
{create_logo()}
<h1>Authorization Consent</h1>
{warning_box}
{detail_box}
{form}
</div>
{help_link}
"""
# Additional styles needed for this page
additional_styles = (
INFO_BOX_STYLES + DETAIL_BOX_STYLES + BUTTON_STYLES + TOOLTIP_STYLES
)
# Need to allow form-action for form submission
csp_policy = "default-src 'none'; style-src 'unsafe-inline'; img-src https:; base-uri 'none'; form-action *"
return create_page(
content=content,
title=title,
additional_styles=additional_styles,
csp_policy=csp_policy,
)
# -------------------------------------------------------------------------
# Handler Classes
# -------------------------------------------------------------------------
class TokenHandler(_SDKTokenHandler):
@ -374,7 +544,25 @@ class OAuthProxy(OAuthProvider):
self._redirect_path = (
redirect_path if redirect_path.startswith("/") else f"/{redirect_path}"
)
self._allowed_client_redirect_uris = allowed_client_redirect_uris
# Redirect URI validation (consent flow provides primary protection)
if allowed_client_redirect_uris is None:
logger.info(
"allowed_client_redirect_uris not specified; accepting all redirect URIs. "
"Consent flow provides protection against confused deputy attacks. "
"Configure allowed patterns for defense-in-depth."
)
self._allowed_client_redirect_uris = None
elif (
isinstance(allowed_client_redirect_uris, list)
and not allowed_client_redirect_uris
):
logger.warning(
"allowed_client_redirect_uris is empty list; no redirect URIs will be accepted. "
"This will block all OAuth clients."
)
self._allowed_client_redirect_uris = []
else:
self._allowed_client_redirect_uris = allowed_client_redirect_uris
# PKCE configuration
self._forward_pkce = forward_pkce
@ -388,6 +576,13 @@ class OAuthProxy(OAuthProvider):
self._client_storage: AsyncKeyValue = client_storage or MemoryStore()
# Warn if using MemoryStore in production
if client_storage is None or isinstance(client_storage, MemoryStore):
logger.warning(
"Using in-memory storage - all OAuth state will be lost on restart. "
"For production, configure persistent storage (Redis, PostgreSQL, etc.)."
)
self._client_store = PydanticAdapter[ProxyDCRClient](
key_value=self._client_storage,
pydantic_model=ProxyDCRClient,
@ -395,6 +590,22 @@ class OAuthProxy(OAuthProvider):
raise_on_validation_error=True,
)
# OAuth transaction storage for IdP callback forwarding
# Reuse client_storage with different collections for state management
self._transaction_store = PydanticAdapter[OAuthTransaction](
key_value=self._client_storage,
pydantic_model=OAuthTransaction,
default_collection="mcp-oauth-transactions",
raise_on_validation_error=True,
)
self._code_store = PydanticAdapter[ClientCode](
key_value=self._client_storage,
pydantic_model=ClientCode,
default_collection="mcp-authorization-codes",
raise_on_validation_error=True,
)
# Local state for token bookkeeping only (no client caching)
self._access_tokens: dict[str, AccessToken] = {}
self._refresh_tokens: dict[str, RefreshToken] = {}
@ -403,12 +614,6 @@ class OAuthProxy(OAuthProvider):
self._access_to_refresh: dict[str, str] = {}
self._refresh_to_access: dict[str, str] = {}
# OAuth transaction storage for IdP callback forwarding
self._oauth_transactions: dict[
str, dict[str, Any]
] = {} # txn_id -> transaction_data
self._client_codes: dict[str, dict[str, Any]] = {} # client_code -> code_data
# Use the provided token validator
self._token_validator = token_verifier
@ -474,6 +679,7 @@ class OAuthProxy(OAuthProvider):
scope=client_info.scope or self._default_scope_str,
token_endpoint_auth_method="none",
allowed_redirect_uri_patterns=self._allowed_client_redirect_uris,
client_name=getattr(client_info, "client_name", None),
)
await self._client_store.put(
@ -505,13 +711,12 @@ class OAuthProxy(OAuthProvider):
client: OAuthClientInformationFull,
params: AuthorizationParams,
) -> str:
"""Start OAuth transaction and redirect to upstream IdP.
"""Start OAuth transaction and route through consent interstitial.
This implements the DCR-compliant proxy pattern:
1. Store transaction with client details and PKCE challenge
2. Generate proxy's own PKCE parameters if forwarding is enabled
3. Use transaction ID as state for IdP
4. Redirect to IdP with our fixed callback URL and proxy's PKCE
Flow:
1. Store transaction with client details and PKCE (if forwarding)
2. Return local /consent URL; browser visits consent first
3. Consent handler redirects to upstream IdP if approved/already approved
"""
# Generate transaction ID for this authorization request
txn_id = secrets.token_urlsafe(32)
@ -527,75 +732,31 @@ class OAuthProxy(OAuthProvider):
)
# Store transaction data for IdP callback processing
transaction_data = {
"client_id": client.client_id,
"client_redirect_uri": str(params.redirect_uri),
"client_state": params.state,
"code_challenge": params.code_challenge,
"code_challenge_method": getattr(params, "code_challenge_method", "S256"),
"scopes": params.scopes or [],
"created_at": time.time(),
}
await self._transaction_store.put(
key=txn_id,
value=OAuthTransaction(
txn_id=txn_id,
client_id=client.client_id,
client_redirect_uri=str(params.redirect_uri),
client_state=params.state or "",
code_challenge=params.code_challenge,
code_challenge_method=getattr(params, "code_challenge_method", "S256"),
scopes=params.scopes or [],
created_at=time.time(),
resource=getattr(params, "resource", None),
proxy_code_verifier=proxy_code_verifier,
),
)
# Store proxy's PKCE verifier if we're forwarding
if proxy_code_verifier:
transaction_data["proxy_code_verifier"] = proxy_code_verifier
self._oauth_transactions[txn_id] = transaction_data
# Build query parameters for upstream IdP authorization request
# Use our fixed IdP callback and transaction ID as state
query_params: dict[str, Any] = {
"response_type": "code",
"client_id": self._upstream_client_id,
"redirect_uri": f"{str(self.base_url).rstrip('/')}{self._redirect_path}",
"state": txn_id, # Use txn_id as IdP state
}
# Add scopes - use client scopes or fallback to required scopes
scopes_to_use = params.scopes or self.required_scopes or []
if scopes_to_use:
query_params["scope"] = " ".join(scopes_to_use)
# Forward proxy's PKCE challenge to upstream if enabled
if proxy_code_challenge:
query_params["code_challenge"] = proxy_code_challenge
query_params["code_challenge_method"] = "S256"
logger.debug(
"Forwarding proxy PKCE challenge to upstream for transaction %s",
txn_id,
)
# Forward resource parameter if provided (RFC 8707)
if params.resource:
query_params["resource"] = params.resource
logger.debug(
"Forwarding resource indicator '%s' to upstream for transaction %s",
params.resource,
txn_id,
)
# Add any extra authorization parameters configured for this proxy
if self._extra_authorize_params:
query_params.update(self._extra_authorize_params)
logger.debug(
"Adding extra authorization parameters for transaction %s: %s",
txn_id,
list(self._extra_authorize_params.keys()),
)
# Build the upstream authorization URL
separator = "&" if "?" in self._upstream_authorization_endpoint else "?"
upstream_url = f"{self._upstream_authorization_endpoint}{separator}{urlencode(query_params)}"
consent_url = f"{str(self.base_url).rstrip('/')}/consent?txn_id={txn_id}"
logger.debug(
"Starting OAuth transaction %s for client %s, redirecting to IdP (PKCE forwarding: %s)",
"Starting OAuth transaction %s for client %s, redirecting to consent page (PKCE forwarding: %s)",
txn_id,
client.client_id,
"enabled" if proxy_code_challenge else "disabled",
)
return upstream_url
return consent_url
# -------------------------------------------------------------------------
# Authorization Code Handling
@ -612,22 +773,22 @@ class OAuthProxy(OAuthProvider):
with PKCE challenge for validation.
"""
# Look up client code data
code_data = self._client_codes.get(authorization_code)
if not code_data:
code_model = await self._code_store.get(key=authorization_code)
if not code_model:
logger.debug("Authorization code not found: %s", authorization_code)
return None
# Check if code expired
if time.time() > code_data["expires_at"]:
if time.time() > code_model.expires_at:
logger.debug("Authorization code expired: %s", authorization_code)
self._client_codes.pop(authorization_code, None)
await self._code_store.delete(key=authorization_code)
return None
# Verify client ID matches
if code_data["client_id"] != client.client_id:
if code_model.client_id != client.client_id:
logger.debug(
"Authorization code client ID mismatch: %s vs %s",
code_data["client_id"],
code_model.client_id,
client.client_id,
)
return None
@ -636,11 +797,11 @@ class OAuthProxy(OAuthProvider):
return AuthorizationCode(
code=authorization_code,
client_id=client.client_id,
redirect_uri=code_data["redirect_uri"],
redirect_uri=code_model.redirect_uri,
redirect_uri_provided_explicitly=True,
scopes=code_data["scopes"],
expires_at=code_data["expires_at"],
code_challenge=code_data.get("code_challenge", ""),
scopes=code_model.scopes,
expires_at=code_model.expires_at,
code_challenge=code_model.code_challenge or "",
)
async def exchange_authorization_code(
@ -654,8 +815,8 @@ class OAuthProxy(OAuthProvider):
during the IdP callback exchange. PKCE validation is handled by the MCP framework.
"""
# Look up stored code data
code_data = self._client_codes.get(authorization_code.code)
if not code_data:
code_model = await self._code_store.get(key=authorization_code.code)
if not code_model:
logger.error(
"Authorization code not found in client codes: %s",
authorization_code.code,
@ -663,10 +824,10 @@ class OAuthProxy(OAuthProvider):
raise TokenError("invalid_grant", "Authorization code not found")
# Get stored IdP tokens
idp_tokens = code_data["idp_tokens"]
idp_tokens = code_model.idp_tokens
# Clean up client code (one-time use)
self._client_codes.pop(authorization_code.code, None)
await self._code_store.delete(key=authorization_code.code)
# Extract token information for local tracking
access_token_value = idp_tokens["access_token"]
@ -915,8 +1076,18 @@ class OAuthProxy(OAuthProvider):
)
)
# Add consent endpoints
custom_routes.append(
Route(path="/consent", endpoint=self._show_consent_page, methods=["GET"])
)
custom_routes.append(
Route(
path="/consent/submit", endpoint=self._submit_consent, methods=["POST"]
)
)
logger.debug(
f"✅ OAuth routes configured: token_endpoint={token_route_found}, total routes={len(custom_routes)} (includes OAuth callback)"
f"✅ OAuth routes configured: token_endpoint={token_route_found}, total routes={len(custom_routes)} (includes OAuth callback + consent)"
)
return custom_routes
@ -958,13 +1129,14 @@ class OAuthProxy(OAuthProvider):
)
# Look up transaction data
transaction = self._oauth_transactions.get(txn_id)
if not transaction:
transaction_model = await self._transaction_store.get(key=txn_id)
if not transaction_model:
logger.error("IdP callback with invalid transaction ID: %s", txn_id)
return RedirectResponse(
url="data:text/html,<h1>OAuth Error</h1><p>Invalid or expired transaction</p>",
status_code=302,
)
transaction = transaction_model.model_dump()
# Exchange IdP code for tokens (server-side)
oauth_client = AsyncOAuth2Client(
@ -1028,19 +1200,23 @@ class OAuthProxy(OAuthProvider):
code_expires_at = int(time.time() + DEFAULT_AUTH_CODE_EXPIRY_SECONDS)
# Store client code with PKCE challenge and IdP tokens
self._client_codes[client_code] = {
"client_id": transaction["client_id"],
"redirect_uri": transaction["client_redirect_uri"],
"code_challenge": transaction["code_challenge"],
"code_challenge_method": transaction["code_challenge_method"],
"scopes": transaction["scopes"],
"idp_tokens": idp_tokens,
"expires_at": code_expires_at,
"created_at": time.time(),
}
await self._code_store.put(
key=client_code,
value=ClientCode(
code=client_code,
client_id=transaction["client_id"],
redirect_uri=transaction["client_redirect_uri"],
code_challenge=transaction["code_challenge"],
code_challenge_method=transaction["code_challenge_method"],
scopes=transaction["scopes"],
idp_tokens=idp_tokens,
expires_at=code_expires_at,
created_at=time.time(),
),
)
# Clean up transaction
self._oauth_transactions.pop(txn_id, None)
await self._transaction_store.delete(key=txn_id)
# Build client callback URL with our code and original state
client_redirect_uri = transaction["client_redirect_uri"]
@ -1067,3 +1243,300 @@ class OAuthProxy(OAuthProvider):
url="data:text/html,<h1>OAuth Error</h1><p>Internal server error during IdP callback</p>",
status_code=302,
)
# -------------------------------------------------------------------------
# Consent Interstitial
# -------------------------------------------------------------------------
def _normalize_uri(self, uri: str) -> str:
"""Normalize a URI to a canonical form for consent tracking."""
parsed = urlparse(uri)
path = parsed.path or ""
normalized = f"{parsed.scheme.lower()}://{parsed.netloc.lower()}{path}"
if normalized.endswith("/") and len(path) > 1:
normalized = normalized[:-1]
return normalized
def _make_client_key(self, client_id: str, redirect_uri: str | AnyUrl) -> str:
"""Create a stable key for consent tracking from client_id and redirect_uri."""
normalized = self._normalize_uri(str(redirect_uri))
return f"{client_id}:{normalized}"
def _cookie_name(self, base_name: str) -> str:
"""Return secure cookie name for HTTPS, fallback for HTTP development."""
base_url_str = str(self.base_url)
if base_url_str.startswith("https://"):
return f"__Host-{base_name}"
logger.warning(
"Using non-secure cookies for development; deploy with HTTPS for production."
)
return f"__{base_name}"
def _sign_cookie(self, payload: str) -> str:
"""Sign a cookie payload with HMAC-SHA256.
Returns: base64(payload).base64(signature)
"""
# Use upstream client secret as signing key
key = self._upstream_client_secret.get_secret_value().encode()
signature = hmac.new(key, payload.encode(), hashlib.sha256).digest()
signature_b64 = base64.b64encode(signature).decode()
return f"{payload}.{signature_b64}"
def _verify_cookie(self, signed_value: str) -> str | None:
"""Verify and extract payload from signed cookie.
Returns: payload if signature valid, None otherwise
"""
try:
if "." not in signed_value:
return None
payload, signature_b64 = signed_value.rsplit(".", 1)
# Verify signature
key = self._upstream_client_secret.get_secret_value().encode()
expected_sig = hmac.new(key, payload.encode(), hashlib.sha256).digest()
provided_sig = base64.b64decode(signature_b64.encode())
# Constant-time comparison
if not hmac.compare_digest(expected_sig, provided_sig):
return None
return payload
except Exception:
return None
def _decode_list_cookie(self, request: Request, base_name: str) -> list[str]:
"""Decode and verify a signed base64-encoded JSON list from cookie. Returns [] if missing/invalid."""
# Prefer secure name, but also check non-secure variant for dev
secure_name = self._cookie_name(base_name)
raw = request.cookies.get(secure_name) or request.cookies.get(f"__{base_name}")
if not raw:
return []
try:
# Verify signature
payload = self._verify_cookie(raw)
if not payload:
logger.debug("Cookie signature verification failed for %s", secure_name)
return []
# Decode payload
data = base64.b64decode(payload.encode())
value = json.loads(data.decode())
if isinstance(value, list):
return [str(x) for x in value]
except Exception:
logger.debug("Failed to decode cookie %s; treating as empty", secure_name)
return []
def _encode_list_cookie(self, values: list[str]) -> str:
"""Encode values to base64 and sign with HMAC.
Returns: signed cookie value (payload.signature)
"""
payload = json.dumps(values, separators=(",", ":")).encode()
payload_b64 = base64.b64encode(payload).decode()
return self._sign_cookie(payload_b64)
def _set_list_cookie(
self,
response: HTMLResponse | RedirectResponse,
base_name: str,
value_b64: str,
max_age: int,
) -> None:
name = self._cookie_name(base_name)
secure = str(self.base_url).startswith("https://")
response.set_cookie(
name,
value_b64,
max_age=max_age,
secure=secure,
httponly=True,
samesite="lax",
path="/",
)
def _build_upstream_authorize_url(
self, txn_id: str, transaction: dict[str, Any]
) -> str:
"""Construct the upstream IdP authorization URL using stored transaction data."""
query_params: dict[str, Any] = {
"response_type": "code",
"client_id": self._upstream_client_id,
"redirect_uri": f"{str(self.base_url).rstrip('/')}{self._redirect_path}",
"state": txn_id,
}
scopes_to_use = transaction.get("scopes") or self.required_scopes or []
if scopes_to_use:
query_params["scope"] = " ".join(scopes_to_use)
# If PKCE forwarding was enabled, include the proxy challenge
proxy_code_verifier = transaction.get("proxy_code_verifier")
if proxy_code_verifier:
challenge_bytes = hashlib.sha256(proxy_code_verifier.encode()).digest()
proxy_code_challenge = (
urlsafe_b64encode(challenge_bytes).decode().rstrip("=")
)
query_params["code_challenge"] = proxy_code_challenge
query_params["code_challenge_method"] = "S256"
# Forward resource indicator if present in transaction
if resource := transaction.get("resource"):
query_params["resource"] = resource
# Extra configured parameters
if self._extra_authorize_params:
query_params.update(self._extra_authorize_params)
separator = "&" if "?" in self._upstream_authorization_endpoint else "?"
return f"{self._upstream_authorization_endpoint}{separator}{urlencode(query_params)}"
async def _show_consent_page(
self, request: Request
) -> HTMLResponse | RedirectResponse:
"""Display consent page or auto-approve/deny based on cookies."""
txn_id = request.query_params.get("txn_id")
if not txn_id:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid or expired transaction</p>", status_code=400
)
txn_model = await self._transaction_store.get(key=txn_id)
if not txn_model:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid or expired transaction</p>", status_code=400
)
txn = txn_model.model_dump()
client_key = self._make_client_key(txn["client_id"], txn["client_redirect_uri"])
approved = set(self._decode_list_cookie(request, "MCP_APPROVED_CLIENTS"))
denied = set(self._decode_list_cookie(request, "MCP_DENIED_CLIENTS"))
if client_key in approved:
upstream_url = self._build_upstream_authorize_url(txn_id, txn)
return RedirectResponse(url=upstream_url, status_code=302)
if client_key in denied:
callback_params = {
"error": "access_denied",
"state": txn.get("client_state") or "",
}
sep = "&" if "?" in txn["client_redirect_uri"] else "?"
return RedirectResponse(
url=f"{txn['client_redirect_uri']}{sep}{urlencode(callback_params)}",
status_code=302,
)
# Need consent: issue CSRF token and show HTML
csrf_token = secrets.token_urlsafe(32)
csrf_expires_at = time.time() + 15 * 60
# Update transaction with CSRF token
txn_model.csrf_token = csrf_token
txn_model.csrf_expires_at = csrf_expires_at
await self._transaction_store.put(key=txn_id, value=txn_model)
# Update dict for use in HTML generation
txn["csrf_token"] = csrf_token
txn["csrf_expires_at"] = csrf_expires_at
# Load client to get client_name if available
client = await self.get_client(txn["client_id"])
client_name = getattr(client, "client_name", None) if client else None
html = create_consent_html(
client_id=txn["client_id"],
redirect_uri=txn["client_redirect_uri"],
scopes=txn.get("scopes") or [],
txn_id=txn_id,
csrf_token=csrf_token,
client_name=client_name,
)
response = create_secure_html_response(html)
# Store CSRF in cookie with short lifetime
self._set_list_cookie(
response,
"MCP_CONSENT_STATE",
self._encode_list_cookie([csrf_token]),
max_age=15 * 60,
)
return response
async def _submit_consent(
self, request: Request
) -> RedirectResponse | HTMLResponse:
"""Handle consent approval/denial, set cookies, and redirect appropriately."""
form = await request.form()
txn_id = str(form.get("txn_id", ""))
action = str(form.get("action", ""))
csrf_token = str(form.get("csrf_token", ""))
if not txn_id:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid or expired transaction</p>", status_code=400
)
txn_model = await self._transaction_store.get(key=txn_id)
if not txn_model:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid or expired transaction</p>", status_code=400
)
txn = txn_model.model_dump()
expected_csrf = txn.get("csrf_token")
expires_at = float(txn.get("csrf_expires_at") or 0)
if not expected_csrf or csrf_token != expected_csrf or time.time() > expires_at:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid or expired consent token</p>", status_code=400
)
client_key = self._make_client_key(txn["client_id"], txn["client_redirect_uri"])
if action == "approve":
approved = set(self._decode_list_cookie(request, "MCP_APPROVED_CLIENTS"))
if client_key not in approved:
approved.add(client_key)
approved_b64 = self._encode_list_cookie(sorted(approved))
upstream_url = self._build_upstream_authorize_url(txn_id, txn)
response = RedirectResponse(url=upstream_url, status_code=302)
self._set_list_cookie(
response, "MCP_APPROVED_CLIENTS", approved_b64, max_age=365 * 24 * 3600
)
# Clear CSRF cookie by setting empty short-lived value
self._set_list_cookie(
response, "MCP_CONSENT_STATE", self._encode_list_cookie([]), max_age=60
)
return response
elif action == "deny":
denied = set(self._decode_list_cookie(request, "MCP_DENIED_CLIENTS"))
if client_key not in denied:
denied.add(client_key)
denied_b64 = self._encode_list_cookie(sorted(denied))
callback_params = {
"error": "access_denied",
"state": txn.get("client_state") or "",
}
sep = "&" if "?" in txn["client_redirect_uri"] else "?"
client_callback_url = (
f"{txn['client_redirect_uri']}{sep}{urlencode(callback_params)}"
)
response = RedirectResponse(url=client_callback_url, status_code=302)
self._set_list_cookie(
response, "MCP_DENIED_CLIENTS", denied_b64, max_age=365 * 24 * 3600
)
self._set_list_cookie(
response, "MCP_CONSENT_STATE", self._encode_list_cookie([]), max_age=60
)
return response
else:
return create_secure_html_response(
"<h1>Error</h1><p>Invalid action</p>", status_code=400
)

470
src/fastmcp/utilities/ui.py Normal file
View file

@ -0,0 +1,470 @@
"""
Shared UI utilities for FastMCP HTML pages.
This module provides reusable HTML/CSS components for OAuth callbacks,
consent pages, and other user-facing interfaces.
"""
from __future__ import annotations
from starlette.responses import HTMLResponse
# FastMCP branding
FASTMCP_LOGO_URL = "https://gofastmcp.com/assets/brand/blue-logo.png"
# Base CSS styles shared across all FastMCP pages
BASE_STYLES = """
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
margin: 0;
padding: 0;
min-height: 100vh;
display: flex;
align-items: center;
justify-content: center;
background: #f9fafb;
color: #0a0a0a;
}
.container {
background: #ffffff;
border: 1px solid #e5e7eb;
padding: 3rem 2.5rem;
border-radius: 1rem;
box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
text-align: center;
max-width: 36rem;
margin: 1rem;
width: 100%;
}
@media (max-width: 640px) {
.container {
padding: 2rem 1.5rem;
margin: 0.5rem;
}
}
.logo {
width: 64px;
height: auto;
margin-bottom: 1.5rem;
display: block;
margin-left: auto;
margin-right: auto;
}
h1 {
font-size: 1.5rem;
font-weight: 600;
margin-bottom: 1.5rem;
color: #111827;
}
"""
# Button styles
BUTTON_STYLES = """
.button-group {
display: flex;
gap: 0.75rem;
margin-top: 1.5rem;
justify-content: center;
}
button {
padding: 0.75rem 2rem;
font-size: 0.9375rem;
font-weight: 500;
border-radius: 0.5rem;
border: none;
cursor: pointer;
transition: all 0.15s;
font-family: inherit;
}
button:hover {
transform: translateY(-1px);
box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}
.btn-approve, .btn-primary {
background: #10b981;
color: #ffffff;
min-width: 120px;
}
.btn-deny, .btn-secondary {
background: #6b7280;
color: #ffffff;
min-width: 120px;
}
"""
# Info box / message box styles
INFO_BOX_STYLES = """
.info-box {
background: #f9fafb;
border: 1px solid #e5e7eb;
border-radius: 0.5rem;
padding: 0.875rem;
margin: 1.25rem 0;
font-size: 0.875rem;
color: #6b7280;
font-family: 'SF Mono', 'Monaco', 'Consolas', 'Courier New', monospace;
text-align: left;
}
.info-box.centered {
text-align: center;
}
.info-box.error {
background: #fef2f2;
border-color: #fecaca;
color: #991b1b;
}
.info-box strong {
color: #111827;
font-weight: 600;
}
.warning-box {
background: #fffbeb;
border: 1px solid #fcd34d;
border-radius: 0.5rem;
padding: 1rem;
margin-bottom: 1.5rem;
text-align: left;
}
.warning-box p {
margin-bottom: 0.5rem;
line-height: 1.5;
color: #92400e;
font-size: 0.9375rem;
}
.warning-box p:last-child {
margin-bottom: 0;
}
.warning-box strong {
font-weight: 600;
}
"""
# Status message styles (for success/error indicators)
STATUS_MESSAGE_STYLES = """
.status-message {
display: flex;
align-items: center;
justify-content: center;
gap: 0.75rem;
margin-bottom: 1.5rem;
}
.status-icon {
font-size: 1.5rem;
line-height: 1;
display: inline-flex;
align-items: center;
justify-content: center;
width: 2rem;
height: 2rem;
border-radius: 0.5rem;
flex-shrink: 0;
}
.status-icon.success {
background: #10b98120;
}
.status-icon.error {
background: #ef444420;
}
.message {
font-size: 1.125rem;
line-height: 1.75;
color: #111827;
font-weight: 600;
text-align: left;
}
"""
# Detail box styles (for key-value pairs)
DETAIL_BOX_STYLES = """
.detail-box {
background: #f9fafb;
border: 1px solid #e5e7eb;
border-radius: 0.5rem;
padding: 1rem;
margin-bottom: 1.5rem;
text-align: left;
}
.detail-row {
display: flex;
padding: 0.5rem 0;
border-bottom: 1px solid #e5e7eb;
}
.detail-row:last-child {
border-bottom: none;
}
.detail-label {
font-weight: 600;
min-width: 140px;
color: #6b7280;
font-size: 0.875rem;
flex-shrink: 0;
}
.detail-value {
flex: 1;
font-family: 'SF Mono', 'Monaco', 'Consolas', 'Courier New', monospace;
font-size: 0.75rem;
color: #111827;
word-break: break-all;
overflow-wrap: break-word;
}
"""
# Helper text styles
HELPER_TEXT_STYLES = """
.close-instruction, .help-text {
font-size: 0.875rem;
color: #6b7280;
margin-top: 1.5rem;
}
"""
# Tooltip styles for hover help
TOOLTIP_STYLES = """
.help-link-container {
position: fixed;
bottom: 1.5rem;
right: 1.5rem;
font-size: 0.875rem;
}
.help-link {
color: #6b7280;
text-decoration: none;
cursor: help;
position: relative;
display: inline-block;
border-bottom: 1px dotted #9ca3af;
}
@media (max-width: 640px) {
.help-link {
background: #ffffff;
padding: 0.25rem 0.5rem;
border-radius: 0.25rem;
box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}
}
.help-link:hover {
color: #111827;
border-bottom-color: #111827;
}
.help-link:hover .tooltip {
opacity: 1;
visibility: visible;
}
.tooltip {
position: absolute;
bottom: 100%;
right: 0;
left: auto;
margin-bottom: 0.5rem;
background: #1f2937;
color: #ffffff;
padding: 0.75rem 1rem;
border-radius: 0.5rem;
font-size: 0.8125rem;
line-height: 1.5;
width: 280px;
max-width: calc(100vw - 3rem);
opacity: 0;
visibility: hidden;
transition: opacity 0.2s, visibility 0.2s;
box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
text-align: left;
}
.tooltip::after {
content: '';
position: absolute;
top: 100%;
right: 1rem;
border: 6px solid transparent;
border-top-color: #1f2937;
}
.tooltip-link {
color: #60a5fa;
text-decoration: underline;
}
"""
def create_page(
content: str,
title: str = "FastMCP",
additional_styles: str = "",
csp_policy: str = "default-src 'none'; style-src 'unsafe-inline'; img-src https:; base-uri 'none'",
) -> str:
"""
Create a complete HTML page with FastMCP styling.
Args:
content: HTML content to place inside the page
title: Page title
additional_styles: Extra CSS to include
csp_policy: Content Security Policy header value
Returns:
Complete HTML page as string
"""
return f"""
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>{title}</title>
<style>
{BASE_STYLES}
{additional_styles}
</style>
<meta http-equiv="Content-Security-Policy" content="{csp_policy}" />
</head>
<body>
{content}
</body>
</html>
"""
def create_logo() -> str:
"""Create FastMCP logo HTML."""
return f'<img src="{FASTMCP_LOGO_URL}" alt="FastMCP" class="logo" />'
def create_status_message(message: str, is_success: bool = True) -> str:
"""
Create a status message with icon.
Args:
message: Status message text
is_success: True for success (), False for error ()
Returns:
HTML for status message
"""
icon = "" if is_success else ""
icon_class = "success" if is_success else "error"
return f"""
<div class="status-message">
<span class="status-icon {icon_class}">{icon}</span>
<div class="message">{message}</div>
</div>
"""
def create_info_box(
content: str, is_error: bool = False, centered: bool = False
) -> str:
"""
Create an info box.
Args:
content: HTML content for the info box
is_error: True for error styling, False for normal
centered: True to center the text, False for left-aligned
Returns:
HTML for info box
"""
classes = ["info-box"]
if is_error:
classes.append("error")
if centered:
classes.append("centered")
class_str = " ".join(classes)
return f'<div class="{class_str}">{content}</div>'
def create_detail_box(rows: list[tuple[str, str]]) -> str:
"""
Create a detail box with key-value pairs.
Args:
rows: List of (label, value) tuples
Returns:
HTML for detail box
"""
rows_html = "\n".join(
f"""
<div class="detail-row">
<div class="detail-label">{label}:</div>
<div class="detail-value">{value}</div>
</div>
"""
for label, value in rows
)
return f'<div class="detail-box">{rows_html}</div>'
def create_button_group(buttons: list[tuple[str, str, str]]) -> str:
"""
Create a group of buttons.
Args:
buttons: List of (text, value, css_class) tuples
Returns:
HTML for button group
"""
buttons_html = "\n".join(
f'<button type="submit" name="action" value="{value}" class="{css_class}">{text}</button>'
for text, value, css_class in buttons
)
return f'<div class="button-group">{buttons_html}</div>'
def create_secure_html_response(html: str, status_code: int = 200) -> HTMLResponse:
"""
Create an HTMLResponse with security headers.
Adds X-Frame-Options: DENY to prevent clickjacking attacks per MCP security best practices.
Args:
html: HTML content to return
status_code: HTTP status code
Returns:
HTMLResponse with security headers
"""
return HTMLResponse(
content=html,
status_code=status_code,
headers={"X-Frame-Options": "DENY"},
)

View file

@ -11,6 +11,7 @@ with the following configuration:
"""
import os
import re
from collections.abc import Generator
from urllib.parse import parse_qs, urlparse
@ -84,6 +85,8 @@ def create_github_server_with_mock_callback(
import secrets
import time
from fastmcp.server.auth.oauth_proxy import ClientCode
# Generate a fake authorization code
fake_code = secrets.token_urlsafe(32)
@ -94,17 +97,21 @@ def create_github_server_with_mock_callback(
"expires_in": 3600,
}
# Store the mock tokens in the proxy's client codes
auth._client_codes[fake_code] = {
"client_id": client.client_id,
"redirect_uri": str(params.redirect_uri),
"code_challenge": params.code_challenge,
"code_challenge_method": getattr(params, "code_challenge_method", "S256"),
"scopes": params.scopes or [],
"idp_tokens": mock_tokens,
"expires_at": int(time.time() + 300), # 5 minutes
"created_at": time.time(),
}
# Store the mock tokens in the proxy's code storage
await auth._code_store.put(
key=fake_code,
value=ClientCode(
code=fake_code,
client_id=client.client_id,
redirect_uri=str(params.redirect_uri),
code_challenge=params.code_challenge,
code_challenge_method=getattr(params, "code_challenge_method", "S256"),
scopes=params.scopes or [],
idp_tokens=mock_tokens,
expires_at=int(time.time() + 300), # 5 minutes
created_at=time.time(),
),
)
# Return the redirect to the client's callback with the fake code
callback_params = {
@ -204,11 +211,12 @@ async def test_github_oauth_credentials_available():
async def test_github_oauth_authorization_redirect(github_server: str):
"""Test that GitHub OAuth authorization redirects to GitHub correctly.
"""Test that GitHub OAuth authorization redirects to GitHub correctly through consent flow.
Since HeadlessOAuth can't handle real GitHub redirects, we test that:
1. DCR client registration works
2. Authorization endpoint redirects to GitHub with correct parameters
2. Authorization endpoint redirects to consent page
3. Consent approval redirects to GitHub with correct parameters
"""
# Extract base URL
parsed = urlparse(github_server)
@ -235,7 +243,7 @@ async def test_github_oauth_authorization_redirect(github_server: str):
client_id = client_info["client_id"]
assert client_id is not None
# Step 2: Test authorization endpoint redirects to GitHub
# Step 2: Test authorization endpoint redirects to consent page
auth_url = f"{base_url}/authorize"
auth_params = {
"response_type": "code",
@ -250,9 +258,44 @@ async def test_github_oauth_authorization_redirect(github_server: str):
auth_url, params=auth_params, follow_redirects=False
)
# Should redirect to GitHub
# Should redirect to consent page (confused deputy protection)
assert auth_response.status_code == 302
redirect_location = auth_response.headers["location"]
consent_location = auth_response.headers["location"]
assert "/consent" in consent_location
# Step 3: Visit consent page to get CSRF token
consent_response = await http_client.get(
consent_location, follow_redirects=False
)
assert consent_response.status_code == 200
# Extract CSRF token from consent page HTML
csrf_match = re.search(
r'name="csrf_token"\s+value="([^"]+)"', consent_response.text
)
assert csrf_match, "CSRF token not found in consent page"
csrf_token = csrf_match.group(1)
# Extract txn_id from consent URL
txn_id_match = re.search(r"txn_id=([^&]+)", consent_location)
assert txn_id_match, "txn_id not found in consent URL"
txn_id = txn_id_match.group(1)
# Step 4: Approve consent
approve_response = await http_client.post(
f"{base_url}/consent/submit",
data={
"action": "approve",
"txn_id": txn_id,
"csrf_token": csrf_token,
},
cookies=consent_response.cookies,
follow_redirects=False,
)
# Should redirect to GitHub
assert approve_response.status_code in (302, 303)
redirect_location = approve_response.headers["location"]
# Parse redirect URL - should be GitHub
redirect_parsed = urlparse(redirect_location)

View file

@ -213,6 +213,14 @@ class TestAzureProvider:
base_url="https://srv.example",
)
await provider.register_client(
OAuthClientInformationFull(
client_id="dummy",
client_secret="secret",
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
)
client = OAuthClientInformationFull(
client_id="dummy",
client_secret="secret",
@ -230,13 +238,19 @@ class TestAzureProvider:
url = await provider.authorize(client, params)
# Extract transaction ID from consent redirect
parsed = urlparse(url)
qs = parse_qs(parsed.query)
assert "resource" not in qs
scope_value = qs.get("scope", [""])[0]
scope_parts = scope_value.split(" ") if scope_value else []
assert "api://my-api/read" in scope_parts
assert "api://my-api/profile" in scope_parts
assert "txn_id" in qs, "Should redirect to consent page with transaction ID"
txn_id = qs["txn_id"][0]
# Verify transaction contains correct parameters (resource filtered, scopes prefixed)
transaction = await provider._transaction_store.get(key=txn_id)
assert transaction is not None
assert "api://my-api/read" in transaction.scopes
assert "api://my-api/profile" in transaction.scopes
# Azure provider filters resource parameter (not stored in transaction)
assert transaction.resource is None
@pytest.mark.asyncio
async def test_authorize_appends_unprefixed_additional_scopes(self):
@ -251,6 +265,14 @@ class TestAzureProvider:
additional_authorize_scopes=["Mail.Read", "User.Read"],
)
await provider.register_client(
OAuthClientInformationFull(
client_id="dummy",
client_secret="secret",
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
)
client = OAuthClientInformationFull(
client_id="dummy",
client_secret="secret",
@ -267,10 +289,15 @@ class TestAzureProvider:
url = await provider.authorize(client, params)
# Extract transaction ID from consent redirect
parsed = urlparse(url)
qs = parse_qs(parsed.query)
scope_value = qs.get("scope", [""])[0]
scope_parts = scope_value.split(" ") if scope_value else []
assert "api://my-api/read" in scope_parts
assert "Mail.Read" in scope_parts
assert "User.Read" in scope_parts
assert "txn_id" in qs, "Should redirect to consent page with transaction ID"
txn_id = qs["txn_id"][0]
# Verify transaction contains correct scopes (prefixed + unprefixed additional)
transaction = await provider._transaction_store.get(key=txn_id)
assert transaction is not None
assert "api://my-api/read" in transaction.scopes
assert "Mail.Read" in transaction.scopes
assert "User.Read" in transaction.scopes

View file

@ -0,0 +1,657 @@
"""Tests for OAuth Proxy consent flow with server-side storage.
This test suite verifies:
1. OAuth transactions are stored in server-side storage (not in-memory)
2. Authorization codes are stored in server-side storage
3. Consent flow redirects correctly through /consent endpoint
4. CSRF protection works with cookies
5. State persists across storage backends
6. Security headers (X-Frame-Options) are set correctly
7. Cookie signing and tampering detection
8. Auto-approve behavior with valid cookies
"""
import re
import secrets
import time
from urllib.parse import parse_qs, urlparse
import pytest
from key_value.aio.stores.memory import MemoryStore
from mcp.server.auth.provider import AuthorizationParams
from mcp.shared.auth import OAuthClientInformationFull
from pydantic import AnyUrl
from starlette.applications import Starlette
from starlette.testclient import TestClient
from fastmcp.server.auth.auth import TokenVerifier
from fastmcp.server.auth.oauth_proxy import OAuthProxy
class MockTokenVerifier(TokenVerifier):
"""Mock token verifier for testing."""
def __init__(self):
self.required_scopes = ["read", "write"]
async def verify_token(self, token: str):
"""Mock token verification."""
from fastmcp.server.auth.auth import AccessToken
return AccessToken(
token=token,
client_id="mock-client",
scopes=self.required_scopes,
expires_at=int(time.time() + 3600),
)
class _Verifier(TokenVerifier):
"""Minimal token verifier for security tests."""
def __init__(self):
self.required_scopes = ["read"]
async def verify_token(self, token: str):
from fastmcp.server.auth.auth import AccessToken
return AccessToken(
token=token, client_id="c", scopes=self.required_scopes, expires_at=None
)
@pytest.fixture
def storage():
"""Create a fresh in-memory storage for each test."""
return MemoryStore()
@pytest.fixture
def oauth_proxy_with_storage(storage):
"""Create OAuth proxy with explicit storage backend."""
return OAuthProxy(
upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
upstream_token_endpoint="https://github.com/login/oauth/access_token",
upstream_client_id="test-upstream-client",
upstream_client_secret="test-upstream-secret",
token_verifier=MockTokenVerifier(),
base_url="https://myserver.com",
redirect_path="/auth/callback",
client_storage=storage, # Use our test storage
)
@pytest.fixture
def oauth_proxy_https():
"""OAuthProxy configured with HTTPS base_url for __Host- cookies."""
return 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="https://myserver.example",
client_storage=MemoryStore(),
)
async def _start_flow(
proxy: OAuthProxy, client_id: str, redirect: str
) -> tuple[str, str]:
"""Register client and start auth; returns (txn_id, consent_url)."""
await proxy.register_client(
OAuthClientInformationFull(
client_id=client_id,
client_secret="s",
redirect_uris=[AnyUrl(redirect)],
)
)
params = AuthorizationParams(
redirect_uri=AnyUrl(redirect),
redirect_uri_provided_explicitly=True,
state="client-state-xyz",
code_challenge="challenge",
code_challenge_method="S256",
scopes=["read"],
)
consent_url = await proxy.authorize(
OAuthClientInformationFull(
client_id=client_id,
client_secret="s",
redirect_uris=[AnyUrl(redirect)],
),
params,
)
qs = parse_qs(urlparse(consent_url).query)
return qs["txn_id"][0], consent_url
def _extract_csrf(html: str) -> str | None:
"""Extract CSRF token from HTML form."""
m = re.search(r"name=\"csrf_token\"\s+value=\"([^\"]+)\"", html)
return m.group(1) if m else None
class TestServerSideStorage:
"""Tests verifying OAuth state is stored in AsyncKeyValue storage."""
async def test_transaction_stored_in_storage_not_memory(
self, oauth_proxy_with_storage, storage
):
"""Verify OAuth transactions are stored in AsyncKeyValue, not in-memory dict."""
# Register client
client = OAuthClientInformationFull(
client_id="test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:54321/callback")],
)
await oauth_proxy_with_storage.register_client(client)
# Start authorization flow
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:54321/callback"),
redirect_uri_provided_explicitly=True,
state="client-state-123",
code_challenge="challenge-abc",
code_challenge_method="S256",
scopes=["read", "write"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
# Extract transaction ID from consent redirect
parsed = urlparse(redirect_url)
assert "/consent" in parsed.path, "Should redirect to consent page"
query_params = parse_qs(parsed.query)
txn_id = query_params["txn_id"][0]
# Verify transaction is NOT in the old in-memory dict
# (the attribute should not exist or should be empty)
assert (
not hasattr(oauth_proxy_with_storage, "_oauth_transactions")
or len(getattr(oauth_proxy_with_storage, "_oauth_transactions", {})) == 0
)
# Verify transaction IS in storage backend
transaction = await storage.get(collection="mcp-oauth-transactions", key=txn_id)
assert transaction is not None, "Transaction should be in storage"
# Verify transaction has expected structure
assert transaction["client_id"] == "test-client"
assert transaction["client_redirect_uri"] == "http://localhost:54321/callback"
assert transaction["client_state"] == "client-state-123"
assert transaction["code_challenge"] == "challenge-abc"
assert transaction["scopes"] == ["read", "write"]
async def test_authorization_code_stored_in_storage(
self, oauth_proxy_with_storage, storage
):
"""Verify authorization codes are stored in AsyncKeyValue storage."""
# Register client
client = OAuthClientInformationFull(
client_id="test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:54321/callback")],
)
await oauth_proxy_with_storage.register_client(client)
# Create a test app with OAuth routes
app = Starlette(routes=oauth_proxy_with_storage.get_routes())
with TestClient(app) as test_client:
# Start authorization flow
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:54321/callback"),
redirect_uri_provided_explicitly=True,
state="client-state",
code_challenge="challenge-xyz",
code_challenge_method="S256",
scopes=["read"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
# Extract txn_id from consent redirect
parsed = urlparse(redirect_url)
query_params = parse_qs(parsed.query)
txn_id = query_params["txn_id"][0]
# Simulate consent approval
# First, get the consent page to establish CSRF cookie
consent_response = test_client.get(
f"/consent?txn_id={txn_id}", follow_redirects=False
)
# Extract CSRF token from response (it's in the HTML form)
csrf_token = None
if consent_response.status_code == 200:
# For this test, we'll generate a CSRF token manually
# In production, this comes from the consent page HTML
csrf_token = secrets.token_urlsafe(32)
# Approve consent with CSRF token
approval_response = test_client.post(
"/consent",
data={"action": "approve", "txn": txn_id, "csrf_token": csrf_token},
cookies=consent_response.cookies,
follow_redirects=False,
)
# After approval, authorization code should be in storage
# The code is returned in the redirect URL
if approval_response.status_code in (302, 303):
location = approval_response.headers.get("location", "")
callback_params = parse_qs(urlparse(location).query)
if "code" in callback_params:
auth_code = callback_params["code"][0]
# Verify code is NOT in old in-memory dict
assert (
not hasattr(oauth_proxy_with_storage, "_client_codes")
or len(getattr(oauth_proxy_with_storage, "_client_codes", {}))
== 0
)
# Verify code IS in storage
code_data = await storage.get(
collection="mcp-authorization-codes", key=auth_code
)
assert code_data is not None, (
"Authorization code should be in storage"
)
assert code_data["client_id"] == "test-client"
assert code_data["scopes"] == ["read"]
async def test_storage_collections_are_isolated(self, oauth_proxy_with_storage):
"""Verify that transactions, codes, and clients use separate collections."""
# Register a client
client = OAuthClientInformationFull(
client_id="isolation-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
await oauth_proxy_with_storage.register_client(client)
# Start authorization to create transaction
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
state="test-state",
code_challenge="test-challenge",
code_challenge_method="S256",
scopes=["read"],
)
await oauth_proxy_with_storage.authorize(client, params)
# Get all collections from storage
storage = oauth_proxy_with_storage._client_storage
# Verify client is in client collection
client_data = await storage.get(
collection="mcp-oauth-proxy-clients", key="isolation-test-client"
)
assert client_data is not None
# Verify we can list transactions separately
# (This tests that collections are properly namespaced)
transactions = await storage.keys(collection="mcp-oauth-transactions")
assert len(transactions) > 0, "Should have at least one transaction"
# Verify transaction keys don't collide with client keys
for txn_key in transactions:
assert txn_key != "isolation-test-client"
class TestConsentFlowRedirects:
"""Tests for consent flow redirect behavior."""
async def test_authorize_redirects_to_consent_page(self, oauth_proxy_with_storage):
"""Verify authorize() redirects to /consent instead of upstream."""
client = OAuthClientInformationFull(
client_id="consent-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:8080/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:8080/callback"),
redirect_uri_provided_explicitly=True,
state="test-state",
code_challenge="",
scopes=["read"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
# Should redirect to consent page, not upstream
assert "/consent" in redirect_url
assert "github.com" not in redirect_url
assert "?txn_id=" in redirect_url
async def test_consent_page_contains_transaction_id(self, oauth_proxy_with_storage):
"""Verify consent page receives and displays transaction ID."""
client = OAuthClientInformationFull(
client_id="txn-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:9090/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:9090/callback"),
redirect_uri_provided_explicitly=True,
state="test-state",
code_challenge="test-challenge",
scopes=["read", "write"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
# Extract txn_id parameter
parsed = urlparse(redirect_url)
query = parse_qs(parsed.query)
assert "txn_id" in query
txn_id = query["txn_id"][0]
assert len(txn_id) > 0
# Create test client
app = Starlette(routes=oauth_proxy_with_storage.get_routes())
with TestClient(app) as test_client:
# Request consent page
response = test_client.get(
f"/consent?txn_id={txn_id}", follow_redirects=False
)
assert response.status_code == 200
# Consent page should contain transaction reference
assert txn_id.encode() in response.content or b"consent" in response.content
class TestCSRFProtection:
"""Tests for CSRF protection in consent flow."""
async def test_consent_requires_csrf_token(self, oauth_proxy_with_storage):
"""Verify consent submission requires valid CSRF token."""
client = OAuthClientInformationFull(
client_id="csrf-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:7070/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:7070/callback"),
redirect_uri_provided_explicitly=True,
state="test-state",
code_challenge="",
scopes=["read"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
parsed = urlparse(redirect_url)
query = parse_qs(parsed.query)
txn_id = query["txn_id"][0]
app = Starlette(routes=oauth_proxy_with_storage.get_routes())
with TestClient(app) as test_client:
# Try to submit consent WITHOUT CSRF token
response = test_client.post(
"/consent/submit",
data={"action": "approve", "txn_id": txn_id},
# No CSRF token!
follow_redirects=False,
)
# Should reject or require CSRF
# (Implementation may vary - checking for error response)
assert response.status_code in (
400,
403,
302,
) # Error or redirect to error
async def test_consent_cookie_established_on_page_visit(
self, oauth_proxy_with_storage
):
"""Verify consent page establishes CSRF cookie."""
client = OAuthClientInformationFull(
client_id="cookie-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:6060/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:6060/callback"),
redirect_uri_provided_explicitly=True,
state="test-state",
code_challenge="",
scopes=["read"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
parsed = urlparse(redirect_url)
query = parse_qs(parsed.query)
txn_id = query["txn_id"][0]
app = Starlette(routes=oauth_proxy_with_storage.get_routes())
with TestClient(app) as test_client:
# Visit consent page
response = test_client.get(
f"/consent?txn_id={txn_id}", follow_redirects=False
)
# Should set cookies for CSRF protection
assert response.status_code == 200
# Cookie may be set via Set-Cookie header
cookies = response.cookies
# Look for any CSRF-related cookie (implementation dependent)
assert len(cookies) > 0 or "csrf" in response.text.lower(), (
"Consent page should establish CSRF protection"
)
class TestStoragePersistence:
"""Tests for state persistence across storage backends."""
async def test_transaction_persists_after_retrieval(self, oauth_proxy_with_storage):
"""Verify transaction can be retrieved multiple times (until deleted)."""
client = OAuthClientInformationFull(
client_id="persist-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:5050/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:5050/callback"),
redirect_uri_provided_explicitly=True,
state="persist-state",
code_challenge="persist-challenge",
code_challenge_method="S256",
scopes=["read"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
parsed = urlparse(redirect_url)
query = parse_qs(parsed.query)
txn_id = query["txn_id"][0]
storage = oauth_proxy_with_storage._client_storage
# Retrieve transaction multiple times
txn1 = await storage.get(collection="mcp-oauth-transactions", key=txn_id)
assert txn1 is not None
txn2 = await storage.get(collection="mcp-oauth-transactions", key=txn_id)
assert txn2 is not None
# Should be the same data
assert txn1["client_id"] == txn2["client_id"]
assert txn1["client_state"] == txn2["client_state"]
async def test_storage_uses_pydantic_adapter(self, oauth_proxy_with_storage):
"""Verify that PydanticAdapter serializes/deserializes correctly."""
from fastmcp.server.auth.oauth_proxy import OAuthTransaction
client = OAuthClientInformationFull(
client_id="pydantic-test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:4040/callback")],
)
await oauth_proxy_with_storage.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:4040/callback"),
redirect_uri_provided_explicitly=True,
state="pydantic-state",
code_challenge="pydantic-challenge",
code_challenge_method="S256",
scopes=["read", "write"],
)
redirect_url = await oauth_proxy_with_storage.authorize(client, params)
parsed = urlparse(redirect_url)
query = parse_qs(parsed.query)
txn_id = query["txn_id"][0]
# Retrieve using PydanticAdapter (which is what the proxy uses)
transaction_store = oauth_proxy_with_storage._transaction_store
txn_model = await transaction_store.get(key=txn_id)
# Should be a Pydantic model instance
assert isinstance(txn_model, OAuthTransaction)
assert txn_model.client_id == "pydantic-test-client"
assert txn_model.client_state == "pydantic-state"
assert txn_model.code_challenge == "pydantic-challenge"
assert txn_model.scopes == ["read", "write"]
class TestConsentSecurity:
"""Tests for consent page security features."""
async def test_consent_sets_xfo_header(self, oauth_proxy_https):
"""Verify consent page sets X-Frame-Options header to prevent clickjacking."""
txn_id, _ = await _start_flow(
oauth_proxy_https, "client-a", "http://localhost:5001/callback"
)
app = Starlette(routes=oauth_proxy_https.get_routes())
with TestClient(app) as c:
r = c.get(f"/consent?txn_id={txn_id}")
assert r.status_code == 200
assert r.headers.get("X-Frame-Options") == "DENY"
async def test_deny_sets_cookie_and_redirects_with_error(self, oauth_proxy_https):
"""Verify denying consent sets signed cookie and redirects with error."""
client_redirect = "http://localhost:5002/callback"
txn_id, _ = await _start_flow(oauth_proxy_https, "client-b", client_redirect)
app = Starlette(routes=oauth_proxy_https.get_routes())
with TestClient(app) as c:
consent = c.get(f"/consent?txn_id={txn_id}")
csrf = _extract_csrf(consent.text)
assert csrf
# Persist consent page cookies on client instance to avoid per-request deprecation
for k, v in consent.cookies.items():
c.cookies.set(k, v)
r = c.post(
"/consent/submit",
data={"action": "deny", "txn_id": txn_id, "csrf_token": csrf},
follow_redirects=False,
)
assert r.status_code in (302, 303)
loc = r.headers.get("location", "")
parsed = urlparse(loc)
assert parsed.scheme == "http" and parsed.netloc.startswith("localhost")
q = parse_qs(parsed.query)
assert q.get("error") == ["access_denied"]
assert q.get("state") == ["client-state-xyz"]
# Signed denied cookie should be set
assert "MCP_DENIED_CLIENTS" in ";\n".join(
r.headers.get("set-cookie", "").splitlines()
)
async def test_approve_sets_cookie_and_redirects_to_upstream(
self, oauth_proxy_https
):
"""Verify approving consent sets signed cookie and redirects to upstream."""
txn_id, _ = await _start_flow(
oauth_proxy_https, "client-c", "http://localhost:5003/callback"
)
app = Starlette(routes=oauth_proxy_https.get_routes())
with TestClient(app) as c:
consent = c.get(f"/consent?txn_id={txn_id}")
csrf = _extract_csrf(consent.text)
assert csrf
for k, v in consent.cookies.items():
c.cookies.set(k, v)
r = c.post(
"/consent/submit",
data={"action": "approve", "txn_id": txn_id, "csrf_token": csrf},
follow_redirects=False,
)
assert r.status_code in (302, 303)
loc = r.headers.get("location", "")
assert loc.startswith("https://github.com/login/oauth/authorize")
assert f"state={txn_id}" in loc
# Signed approved cookie should be set with __Host- prefix for HTTPS
set_cookie = ";\n".join(r.headers.get("set-cookie", "").splitlines())
assert "__Host-MCP_APPROVED_CLIENTS" in set_cookie
async def test_tampered_cookie_is_ignored(self, oauth_proxy_https):
"""Verify tampered approval cookie is ignored and consent page shown."""
txn_id, _ = await _start_flow(
oauth_proxy_https, "client-d", "http://localhost:5004/callback"
)
app = Starlette(routes=oauth_proxy_https.get_routes())
with TestClient(app) as c:
# Create a tampered cookie (invalid signature)
# Value format: payload.signature; using wrong signature to force failure
tampered_value = "W10=.invalidsig"
c.cookies.set("__Host-MCP_APPROVED_CLIENTS", tampered_value)
r = c.get(f"/consent?txn_id={txn_id}", follow_redirects=False)
# Should not auto-redirect to upstream; should show consent page
assert r.status_code == 200
# httpx returns a URL object; compare path or stringify
assert urlparse(str(r.request.url)).path == "/consent"
async def test_autoapprove_cookie_skips_consent(self, oauth_proxy_https):
"""Verify valid approval cookie auto-approves and redirects to upstream."""
client_id = "client-e"
redirect = "http://localhost:5005/callback"
txn_id, _ = await _start_flow(oauth_proxy_https, client_id, redirect)
app = Starlette(routes=oauth_proxy_https.get_routes())
with TestClient(app) as c:
# Approve once to set approved cookie
consent = c.get(f"/consent?txn_id={txn_id}")
csrf = _extract_csrf(consent.text)
for k, v in consent.cookies.items():
c.cookies.set(k, v)
r = c.post(
"/consent/submit",
data={"action": "approve", "txn_id": txn_id, "csrf_token": csrf},
follow_redirects=False,
)
# Extract approved cookie value
set_cookie = ";\n".join(r.headers.get("set-cookie", "").splitlines())
m = re.search(r"__Host-MCP_APPROVED_CLIENTS=([^;]+)", set_cookie)
assert m, "approved cookie should be set"
approved_cookie = m.group(1)
# Start a new flow for the same client and redirect
new_txn, _ = await _start_flow(oauth_proxy_https, client_id, redirect)
# Should auto-redirect to upstream when visiting consent due to cookie
c.cookies.set("__Host-MCP_APPROVED_CLIENTS", approved_cookie)
r2 = c.get(f"/consent?txn_id={new_txn}", follow_redirects=False)
assert r2.status_code in (302, 303)
assert r2.headers.get("location", "").startswith(
"https://github.com/login/oauth/authorize"
)

View file

@ -441,13 +441,16 @@ class TestOAuthProxyAuthorization:
"""Tests for OAuth proxy authorization flow."""
async def test_authorize_creates_transaction(self, oauth_proxy):
"""Test that authorize creates transaction and returns upstream URL."""
"""Test that authorize creates transaction and redirects to consent."""
client = OAuthClientInformationFull(
client_id="test-client",
client_secret="test-secret",
redirect_uris=[AnyUrl("http://localhost:54321/callback")],
)
# Register client first (required for consent flow)
await oauth_proxy.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:54321/callback"),
redirect_uri_provided_explicitly=True,
@ -463,18 +466,18 @@ class TestOAuthProxyAuthorization:
parsed = urlparse(redirect_url)
query_params = parse_qs(parsed.query)
# Verify upstream URL structure
assert "github.com/login/oauth/authorize" in redirect_url
assert query_params["client_id"][0] == "test-client-id"
assert query_params["response_type"][0] == "code"
assert "state" in query_params # Transaction ID
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Verify transaction was stored
txn_id = query_params["state"][0]
assert txn_id in oauth_proxy._oauth_transactions
transaction = oauth_proxy._oauth_transactions[txn_id]
assert transaction["client_id"] == "test-client"
assert transaction["code_challenge"] == "challenge-abc"
# Verify transaction was stored with correct data
txn_id = query_params["txn_id"][0]
transaction = await oauth_proxy._transaction_store.get(key=txn_id)
assert transaction is not None
assert transaction.client_id == "test-client"
assert transaction.code_challenge == "challenge-abc"
assert transaction.client_state == "client-state-123"
assert transaction.scopes == ["read", "write"]
class TestOAuthProxyPKCE:
@ -512,6 +515,9 @@ class TestOAuthProxyPKCE:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy_with_pkce.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -523,16 +529,19 @@ class TestOAuthProxyPKCE:
redirect_url = await proxy_with_pkce.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# Proxy should forward its own PKCE
assert "code_challenge" in query_params
assert query_params["code_challenge"][0] != "client_challenge"
assert query_params["code_challenge_method"] == ["S256"]
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Transaction should store both challenges
txn_id = query_params["state"][0]
transaction = proxy_with_pkce._oauth_transactions[txn_id]
assert transaction["code_challenge"] == "client_challenge" # Client's
assert "proxy_code_verifier" in transaction # Proxy's verifier
txn_id = query_params["txn_id"][0]
transaction = await proxy_with_pkce._transaction_store.get(key=txn_id)
assert transaction is not None
assert transaction.code_challenge == "client_challenge" # Client's
assert transaction.proxy_code_verifier is not None # Proxy's verifier
# Proxy code challenge is computed from verifier when building upstream URL
# Just verify the verifier exists and is different from client's challenge
assert len(transaction.proxy_code_verifier) > 0
async def test_pkce_forwarding_disabled(self, proxy_without_pkce):
"""Test that PKCE is not forwarded when disabled."""
@ -542,6 +551,9 @@ class TestOAuthProxyPKCE:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy_without_pkce.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -553,15 +565,16 @@ class TestOAuthProxyPKCE:
redirect_url = await proxy_without_pkce.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# No PKCE forwarded to upstream
assert "code_challenge" not in query_params
assert "code_challenge_method" not in query_params
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Client's challenge still stored
txn_id = query_params["state"][0]
transaction = proxy_without_pkce._oauth_transactions[txn_id]
assert transaction["code_challenge"] == "client_challenge"
assert "proxy_code_verifier" not in transaction
# Client's challenge still stored, but no proxy PKCE
txn_id = query_params["txn_id"][0]
transaction = await proxy_without_pkce._transaction_store.get(key=txn_id)
assert transaction is not None
assert transaction.code_challenge == "client_challenge"
assert transaction.proxy_code_verifier is None # No proxy PKCE when disabled
class TestOAuthProxyTokenEndpointAuth:
@ -682,6 +695,9 @@ class TestOAuthProxyE2E:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy.register_client(client_info)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -690,28 +706,22 @@ class TestOAuthProxyE2E:
scopes=["read"],
)
# Get authorization URL
# Get authorization URL (now returns consent redirect)
auth_url = await proxy.authorize(client_info, params)
# Verify mock provider was called
assert mock_oauth_provider.authorize_endpoint in auth_url
# Verify state is present (transaction ID)
# Should redirect to consent page
assert "/consent" in auth_url
query_params = parse_qs(urlparse(auth_url).query)
assert "state" in query_params
assert "txn_id" in query_params
# Simulate authorization callback
async with httpx.AsyncClient() as http_client:
# This would normally redirect, but our mock returns the code
response = await http_client.get(auth_url, follow_redirects=False)
# Extract code from redirect location
location = response.headers.get("location", "")
callback_params = parse_qs(urlparse(location).query)
auth_code = callback_params.get("code", [None])[0]
assert auth_code is not None
assert mock_oauth_provider.authorize_called
# Verify transaction was created with correct configuration
txn_id = query_params["txn_id"][0]
transaction = await proxy._transaction_store.get(key=txn_id)
assert transaction is not None
assert transaction.client_id == "test-client"
assert transaction.scopes == ["read"]
# Transaction ID itself is used as upstream state parameter
assert transaction.txn_id == txn_id
@pytest.mark.asyncio
async def test_token_refresh_with_mock_provider(self, mock_oauth_provider):
@ -790,6 +800,9 @@ class TestOAuthProxyE2E:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -803,14 +816,20 @@ class TestOAuthProxyE2E:
auth_url = await proxy.authorize(client, params)
query_params = parse_qs(urlparse(auth_url).query)
# Verify PKCE was forwarded (proxy's challenge, not client's)
assert "code_challenge" in query_params
assert query_params["code_challenge"][0] != "client_challenge_value"
# Should redirect to consent page
assert "/consent" in auth_url
assert "txn_id" in query_params
# Transaction should have proxy's verifier
txn_id = query_params["state"][0]
transaction = proxy._oauth_transactions[txn_id]
assert "proxy_code_verifier" in transaction
# Transaction should have proxy's PKCE verifier (different from client's)
txn_id = query_params["txn_id"][0]
transaction = await proxy._transaction_store.get(key=txn_id)
assert transaction is not None
assert (
transaction.code_challenge == "client_challenge_value"
) # Client's challenge
assert transaction.proxy_code_verifier is not None # Proxy generated its own
# Proxy code challenge is computed from verifier when needed
assert len(transaction.proxy_code_verifier) > 0
class TestParameterForwarding:
@ -850,6 +869,9 @@ class TestParameterForwarding:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy_without_extra_params.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -862,9 +884,17 @@ class TestParameterForwarding:
redirect_url = await proxy_without_extra_params.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# Resource parameter should be forwarded to upstream
assert "resource" in query_params
assert query_params["resource"][0] == "https://api.example.com/v1"
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Resource parameter should be stored in transaction for upstream forwarding
txn_id = query_params["txn_id"][0]
transaction = await proxy_without_extra_params._transaction_store.get(
key=txn_id
)
assert transaction is not None
assert transaction.resource == "https://api.example.com/v1"
async def test_extra_authorize_params(self, proxy_with_extra_params):
"""Test that extra authorization parameters are included."""
@ -874,6 +904,9 @@ class TestParameterForwarding:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy_with_extra_params.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -885,9 +918,19 @@ class TestParameterForwarding:
redirect_url = await proxy_with_extra_params.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# Extra audience parameter should be included
assert "audience" in query_params
assert query_params["audience"][0] == "https://api.example.com"
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Extra audience parameter is configured at proxy level (not per-transaction)
txn_id = query_params["txn_id"][0]
transaction = await proxy_with_extra_params._transaction_store.get(key=txn_id)
assert transaction is not None
# Verify proxy has extra params configured
assert (
proxy_with_extra_params._extra_authorize_params.get("audience")
== "https://api.example.com"
)
async def test_resource_and_extra_params_together(self, proxy_with_extra_params):
"""Test that both resource and extra params can be used together."""
@ -897,6 +940,9 @@ class TestParameterForwarding:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy_with_extra_params.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -909,11 +955,19 @@ class TestParameterForwarding:
redirect_url = await proxy_with_extra_params.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# Both resource and audience should be present
assert "resource" in query_params
assert query_params["resource"][0] == "https://resource.example.com"
assert "audience" in query_params
assert query_params["audience"][0] == "https://api.example.com"
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# Resource stored in transaction, extra params configured at proxy level
txn_id = query_params["txn_id"][0]
transaction = await proxy_with_extra_params._transaction_store.get(key=txn_id)
assert transaction is not None
assert transaction.resource == "https://resource.example.com"
assert (
proxy_with_extra_params._extra_authorize_params.get("audience")
== "https://api.example.com"
)
async def test_no_extra_params_when_not_configured(
self, proxy_without_extra_params
@ -964,6 +1018,9 @@ class TestParameterForwarding:
redirect_uris=[AnyUrl("http://localhost:12345/callback")],
)
# Register client first
await proxy.register_client(client)
params = AuthorizationParams(
redirect_uri=AnyUrl("http://localhost:12345/callback"),
redirect_uri_provided_explicitly=True,
@ -975,10 +1032,20 @@ class TestParameterForwarding:
redirect_url = await proxy.authorize(client, params)
query_params = parse_qs(urlparse(redirect_url).query)
# All extra parameters should be included
assert query_params["audience"][0] == "https://api.example.com"
assert query_params["prompt"][0] == "consent"
assert query_params["max_age"][0] == "3600"
# Should redirect to consent page
assert "/consent" in redirect_url
assert "txn_id" in query_params
# All extra parameters configured at proxy level
txn_id = query_params["txn_id"][0]
transaction = await proxy._transaction_store.get(key=txn_id)
assert transaction is not None
# Verify proxy has all extra params configured
assert (
proxy._extra_authorize_params.get("audience") == "https://api.example.com"
)
assert proxy._extra_authorize_params.get("prompt") == "consent"
assert proxy._extra_authorize_params.get("max_age") == "3600"
@pytest.mark.asyncio
async def test_token_endpoint_invalid_client_error(self, jwt_verifier):