Merge pull request #382 from cbcoutinho/renovate/mcp-1.x

fix(deps): update dependency mcp to >=1.23,<1.24
2025-12-12 18:00:04 +01:00
parent 4a79b37714 5166c2c4d7
commit c8da826ef7
5 changed files with 306 additions and 7 deletions
@@ -0,0 +1,174 @@
+"""
+Test that DNS rebinding protection is properly disabled for containerized deployments.
+
+This test verifies that the fix for MCP 1.23.x DNS rebinding protection works correctly.
+Without the fix, requests with Host headers that don't match the default allowed list
+(127.0.0.1:*, localhost:*, [::1]:*) would be rejected with a 421 Misdirected Request error.
+"""
+
+import httpx
+import pytest
+
+
+@pytest.mark.integration
+async def test_accepts_various_host_headers():
+    """Test that the MCP server accepts requests with various Host headers.
+
+    This test simulates what happens in containerized deployments where the Host
+    header might be a k8s service DNS name, a proxied hostname, or other values
+    that don't match the default allowed list.
+
+    Without the DNS rebinding protection fix, these requests would fail with:
+    - 421 Misdirected Request (for Host header mismatch)
+    - 403 Forbidden (for Origin header mismatch)
+    """
+    mcp_url = "http://localhost:8000/mcp"
+
+    # Test various Host headers that would be rejected by DNS rebinding protection
+    test_cases = [
+        {
+            "name": "Kubernetes service DNS",
+            "headers": {
+                "Host": "nextcloud-mcp-server.default.svc.cluster.local:8000",
+                "Content-Type": "application/json",
+                "Accept": "application/json, text/event-stream",
+            },
+        },
+        {
+            "name": "Custom domain",
+            "headers": {
+                "Host": "mcp.example.com:8000",
+                "Content-Type": "application/json",
+                "Accept": "application/json, text/event-stream",
+            },
+        },
+        {
+            "name": "Proxied hostname",
+            "headers": {
+                "Host": "proxy.internal:8000",
+                "Content-Type": "application/json",
+                "Accept": "application/json, text/event-stream",
+            },
+        },
+        {
+            "name": "Default localhost (should always work)",
+            "headers": {
+                "Host": "localhost:8000",
+                "Content-Type": "application/json",
+                "Accept": "application/json, text/event-stream",
+            },
+        },
+    ]
+
+    # Create a simple initialize request payload
+    initialize_request = {
+        "jsonrpc": "2.0",
+        "method": "initialize",
+        "params": {
+            "protocolVersion": "2024-11-05",
+            "capabilities": {},
+            "clientInfo": {"name": "test-client", "version": "1.0.0"},
+        },
+        "id": 1,
+    }
+
+    async with httpx.AsyncClient() as client:
+        for test_case in test_cases:
+            print(f"\n🧪 Testing: {test_case['name']}")
+            print(f"   Host header: {test_case['headers']['Host']}")
+
+            response = await client.post(
+                mcp_url,
+                json=initialize_request,
+                headers=test_case["headers"],
+                timeout=10.0,
+            )
+
+            # With DNS rebinding protection enabled (MCP 1.23 default), these would fail with:
+            # - 421 Misdirected Request (Host header not in allowed list)
+            # - 403 Forbidden (Origin header not in allowed list)
+            #
+            # With our fix (enable_dns_rebinding_protection=False), they should succeed
+            assert response.status_code in [200, 202], (
+                f"Request failed for {test_case['name']}: "
+                f"status={response.status_code}, "
+                f"headers={test_case['headers']}, "
+                f"body={response.text[:200]}"
+            )
+
+            print(f"   ✅ Status: {response.status_code}")
+
+            # For SSE responses (status 200), verify we got SSE format
+            # For JSON responses (status 202), verify we got valid JSON
+            if response.status_code == 200:
+                # SSE response - should start with "event: message" or similar
+                response_text = response.text
+                assert "event:" in response_text or "data:" in response_text, (
+                    f"Expected SSE format for {test_case['name']}, got: {response_text[:200]}"
+                )
+                print("   ✅ Received SSE stream response")
+            elif response.status_code == 202:
+                # JSON response for notifications
+                response_json = response.json()
+                assert "jsonrpc" in response_json or response_json is None, (
+                    f"Invalid response for {test_case['name']}: {response_json}"
+                )
+                print("   ✅ Received JSON response")
+
+
+@pytest.mark.integration
+async def test_dns_rebinding_protection_is_disabled():
+    """Verify that DNS rebinding protection is actually disabled in the configuration.
+
+    This test makes a request that would DEFINITELY fail if DNS rebinding protection
+    was enabled with default settings (only allowing 127.0.0.1:*, localhost:*, [::1]:*).
+    """
+    mcp_url = "http://localhost:8000/mcp"
+
+    # Use a Host header that would NEVER be in the default allowed list
+    malicious_host = "evil.attacker.com:8000"
+
+    initialize_request = {
+        "jsonrpc": "2.0",
+        "method": "initialize",
+        "params": {
+            "protocolVersion": "2024-11-05",
+            "capabilities": {},
+            "clientInfo": {"name": "test-client", "version": "1.0.0"},
+        },
+        "id": 1,
+    }
+
+    async with httpx.AsyncClient() as client:
+        response = await client.post(
+            mcp_url,
+            json=initialize_request,
+            headers={
+                "Host": malicious_host,
+                "Content-Type": "application/json",
+                "Accept": "application/json, text/event-stream",
+            },
+            timeout=10.0,
+        )
+
+        # If DNS rebinding protection was enabled, this would return:
+        # - 421 Misdirected Request (Host header validation failed)
+        #
+        # Since we disabled it, this should succeed (status 200 or 202)
+        assert response.status_code in [200, 202], (
+            f"DNS rebinding protection may still be enabled! "
+            f"Request with Host='{malicious_host}' was rejected: "
+            f"status={response.status_code}, body={response.text[:500]}"
+        )
+
+        # Verify we got a valid response (SSE or JSON)
+        if response.status_code == 200:
+            response_text = response.text
+            assert "event:" in response_text or "data:" in response_text, (
+                f"Expected SSE format, got: {response_text[:200]}"
+            )
+
+        print("✅ DNS rebinding protection is properly disabled")
+        print(
+            f"   Request with Host '{malicious_host}' succeeded: {response.status_code}"
+        )