modelcontextprotocol/python-sdk
Watch
1
0
Fork
You've already forked python-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Require integrity protection for MRTR requestState (#3032)

Browse source
This commit is contained in:
Max 2026-06-30 21:30:32 +01:00 • committed by GitHub
commit 7322ca56f4
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
1 changed files with 3338 additions and 183 deletions
Download patch file Download diff file Expand all files Collapse all files

42
examples/servers/everything-server/mcp_everything_server/server.py
View file

@ -6,16 +6,13 @@ Server implementing all MCP features for conformance testing based on Conformanc
import asyncio
import base64
import binascii
import hashlib
import hmac
import json
import logging
from typing import Annotated, Any
import click
from mcp.server import ServerRequestContext
from mcp.server.mcpserver import Context, MCPServer
from mcp.server.mcpserver import Context, MCPServer, RequestStateSecurity
from mcp.server.mcpserver.prompts.base import UserMessage
from mcp.server.streamable_http import EventCallback, EventMessage, EventStore
from mcp.shared.exceptions import MCPError
@ -47,7 +44,7 @@ from mcp_types import (
TextResourceContents,
UnsubscribeRequestParams,
)
from mcp_types.jsonrpc import INVALID_PARAMS, MISSING_REQUIRED_CLIENT_CAPABILITY
from mcp_types.jsonrpc import MISSING_REQUIRED_CLIENT_CAPABILITY
from pydantic import BaseModel, Field
logger = logging.getLogger(__name__)
@ -100,8 +97,12 @@ watched_resource_content = "Watched resource content"
# Create event store for SSE resumability (SEP-1699)
event_store = InMemoryEventStore()
# Fixed fixture key (RequestStateSecurity requires at least 32 bytes); a real deployment would load a shared secret.
_REQUEST_STATE_KEY = b"everything-server-fixture-request-state-key"
mcp = MCPServer(
name="mcp-conformance-test-server",
request_state_security=RequestStateSecurity(keys=[_REQUEST_STATE_KEY]),
)
@ -497,30 +498,12 @@ async def test_input_required_result_multi_round(ctx: Context) -> str | InputReq
)
# Fixed key for the conformance fixture; a real server would derive or rotate this.
_STATE_HMAC_KEY = b"everything-server-fixture-key"
def _seal_state(payload: str) -> str:
encoded = base64.urlsafe_b64encode(payload.encode()).decode()
sig = hmac.new(_STATE_HMAC_KEY, encoded.encode(), hashlib.sha256).hexdigest()
return f"{encoded}.{sig}"
def _unseal_state(state: str) -> str:
encoded, _, sig = state.partition(".")
expected = hmac.new(_STATE_HMAC_KEY, encoded.encode(), hashlib.sha256).hexdigest()
if not sig or not hmac.compare_digest(sig, expected):
raise MCPError(code=INVALID_PARAMS, message="requestState failed integrity verification")
try:
return base64.urlsafe_b64decode(encoded).decode()
except (binascii.Error, UnicodeDecodeError) as e:
raise MCPError(code=INVALID_PARAMS, message="requestState failed integrity verification") from e
@mcp.tool()
async def test_input_required_result_tampered_state(ctx: Context) -> str | InputRequiredResult:
"""Tests that the server rejects a requestState that fails HMAC verification"""
"""Tests that the server rejects a tampered requestState echo.
The handler stays plaintext; tamper rejection happens in the SDK's request-state boundary.
"""
if ctx.request_state is None:
confirm = ElicitRequest(
params=ElicitRequestFormParams(
@ -528,9 +511,8 @@ async def test_input_required_result_tampered_state(ctx: Context) -> str | Input
requested_schema={"type": "object", "properties": {"ok": {"type": "boolean"}}, "required": ["ok"]},
)
)
return InputRequiredResult(input_requests={"confirm": confirm}, request_state=_seal_state("round-1"))
payload = _unseal_state(ctx.request_state)
return f"state-ok: {payload}"
return InputRequiredResult(input_requests={"confirm": confirm}, request_state="round-1")
return f"state-ok: {ctx.request_state}"
@mcp.tool()