snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

test/malformed_method_test.go

@@ -0,0 +1,159 @@
+/*
+ *
+ * Copyright 2026 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package test
+
+import (
+	"bytes"
+	"context"
+	"net"
+	"testing"
+
+	"golang.org/x/net/http2"
+	"golang.org/x/net/http2/hpack"
+	"google.golang.org/grpc/internal/stubserver"
+
+	testpb "google.golang.org/grpc/interop/grpc_testing"
+)
+
+// TestMalformedMethodPath tests that the server responds with Unimplemented
+// when the method path is malformed. This verifies that the server does not
+// route requests with a malformed method path to the application handler.
+func (s) TestMalformedMethodPath(t *testing.T) {
+	tests := []struct {
+		name       string
+		path       string
+		wantStatus string // string representation of codes.Code
+	}{
+		{
+			name:       "missing_leading_slash",
+			path:       "grpc.testing.TestService/UnaryCall",
+			wantStatus: "12", // Unimplemented
+		},
+		{
+			name:       "empty_path",
+			path:       "",
+			wantStatus: "12", // Unimplemented
+		},
+		{
+			name:       "just_slash",
+			path:       "/",
+			wantStatus: "12", // Unimplemented
+		},
+		{
+			name:       "double_slash",
+			path:       "//grpc.testing.TestService/UnaryCall",
+			wantStatus: "12", // Unimplemented
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+			defer cancel()
+
+			ss := &stubserver.StubServer{
+				UnaryCallF: func(context.Context, *testpb.SimpleRequest) (*testpb.SimpleResponse, error) {
+					return &testpb.SimpleResponse{Payload: &testpb.Payload{Body: []byte("pwned")}}, nil
+				},
+			}
+			if err := ss.Start(nil); err != nil {
+				t.Fatalf("Error starting endpoint server: %v", err)
+			}
+			defer ss.Stop()
+
+			// Open a raw TCP connection to the server and speak HTTP/2 directly.
+			tcpConn, err := net.Dial("tcp", ss.Address)
+			if err != nil {
+				t.Fatalf("Failed to dial tcp: %v", err)
+			}
+			defer tcpConn.Close()
+
+			// Write the HTTP/2 connection preface and the initial settings frame.
+			if _, err := tcpConn.Write([]byte("PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n")); err != nil {
+				t.Fatalf("Failed to write preface: %v", err)
+			}
+			framer := http2.NewFramer(tcpConn, tcpConn)
+			if err := framer.WriteSettings(); err != nil {
+				t.Fatalf("Failed to write settings: %v", err)
+			}
+
+			// Encode and write the HEADERS frame.
+			var headerBuf bytes.Buffer
+			enc := hpack.NewEncoder(&headerBuf)
+			writeHeader := func(name, value string) {
+				enc.WriteField(hpack.HeaderField{Name: name, Value: value})
+			}
+			writeHeader(":method", "POST")
+			writeHeader(":scheme", "http")
+			writeHeader(":authority", ss.Address)
+			writeHeader(":path", tc.path)
+			writeHeader("content-type", "application/grpc")
+			writeHeader("te", "trailers")
+			if err := framer.WriteHeaders(http2.HeadersFrameParam{
+				StreamID:      1,
+				BlockFragment: headerBuf.Bytes(),
+				EndStream:     false,
+				EndHeaders:    true,
+			}); err != nil {
+				t.Fatalf("Failed to write headers: %v", err)
+			}
+
+			// Send a small gRPC-encoded data frame (0 length).
+			if err := framer.WriteData(1, true, []byte{0, 0, 0, 0, 0}); err != nil {
+				t.Fatalf("Failed to write data: %v", err)
+			}
+
+			// Read responses and look for grpc-status.
+			gotStatus := ""
+			dec := hpack.NewDecoder(4096, func(f hpack.HeaderField) {
+				if f.Name == "grpc-status" {
+					gotStatus = f.Value
+				}
+			})
+			done := make(chan struct{})
+			go func() {
+				defer close(done)
+				for {
+					frame, err := framer.ReadFrame()
+					if err != nil {
+						return
+					}
+					if headers, ok := frame.(*http2.HeadersFrame); ok {
+						if _, err := dec.Write(headers.HeaderBlockFragment()); err != nil {
+							return
+						}
+						if headers.StreamEnded() {
+							return
+						}
+					}
+				}
+			}()
+
+			select {
+			case <-done:
+			case <-ctx.Done():
+				t.Fatalf("Timed out waiting for response")
+			}
+
+			if gotStatus != tc.wantStatus {
+				t.Errorf("Got grpc-status %v, want %v", gotStatus, tc.wantStatus)
+			}
+		})
+	}
+}