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

credentials/credentials_ext_test.go

@@ -0,0 +1,538 @@
+/*
+ *
+ * Copyright 2025 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 credentials_test
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"fmt"
+	"math/big"
+	"net"
+	"strings"
+	"testing"
+	"time"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/credentials/insecure"
+	"google.golang.org/grpc/credentials/local"
+	"google.golang.org/grpc/internal/stubserver"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/testdata"
+
+	testgrpc "google.golang.org/grpc/interop/grpc_testing"
+	testpb "google.golang.org/grpc/interop/grpc_testing"
+)
+
+func authorityChecker(ctx context.Context, wantAuthority string) error {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return status.Error(codes.InvalidArgument, "failed to parse metadata")
+	}
+	auths, ok := md[":authority"]
+	if !ok {
+		return status.Error(codes.InvalidArgument, "no authority header")
+	}
+	if len(auths) != 1 {
+		return status.Errorf(codes.InvalidArgument, "expected exactly one authority header, got %v", auths)
+	}
+	if auths[0] != wantAuthority {
+		return status.Errorf(codes.InvalidArgument, "invalid authority header %q, want %q", auths[0], wantAuthority)
+	}
+	return nil
+}
+
+func loadTLSCreds(t *testing.T) (grpc.ServerOption, grpc.DialOption) {
+	t.Helper()
+	cert, err := tls.LoadX509KeyPair(testdata.Path("x509/server1_cert.pem"), testdata.Path("x509/server1_key.pem"))
+	if err != nil {
+		t.Fatalf("Failed to load key pair: %v", err)
+		return nil, nil
+	}
+	serverCreds := grpc.Creds(credentials.NewServerTLSFromCert(&cert))
+
+	clientCreds, err := credentials.NewClientTLSFromFile(testdata.Path("x509/server_ca_cert.pem"), "x.test.example.com")
+	if err != nil {
+		t.Fatalf("Failed to create client credentials: %v", err)
+	}
+	return serverCreds, grpc.WithTransportCredentials(clientCreds)
+}
+
+// Tests the scenario where the `grpc.CallAuthority` call option is used with
+// different transport credentials. The test verifies that the specified
+// authority is correctly propagated to the serve when a correct authority is
+// used.
+func (s) TestCorrectAuthorityWithCreds(t *testing.T) {
+	const authority = "auth.test.example.com"
+	const authorityWithPort = "auth.test.example.com:8010"
+
+	tests := []struct {
+		name         string
+		creds        func(t *testing.T) (grpc.ServerOption, grpc.DialOption)
+		expectedAuth string
+	}{
+		{
+			name: "Insecure",
+			creds: func(*testing.T) (grpc.ServerOption, grpc.DialOption) {
+				c := insecure.NewCredentials()
+				return grpc.Creds(c), grpc.WithTransportCredentials(c)
+			},
+			expectedAuth: authority,
+		},
+		{
+			name: "Local",
+			creds: func(*testing.T) (grpc.ServerOption, grpc.DialOption) {
+				c := local.NewCredentials()
+				return grpc.Creds(c), grpc.WithTransportCredentials(c)
+			},
+			expectedAuth: authority,
+		},
+		{
+			name: "TLS",
+			creds: func(t *testing.T) (grpc.ServerOption, grpc.DialOption) {
+				return loadTLSCreds(t)
+			},
+			expectedAuth: authority,
+		},
+		{
+			name: "TLSAuthorityWithPort",
+			creds: func(t *testing.T) (grpc.ServerOption, grpc.DialOption) {
+				return loadTLSCreds(t)
+			},
+			expectedAuth: authorityWithPort,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ss := &stubserver.StubServer{
+				EmptyCallF: func(ctx context.Context, _ *testpb.Empty) (*testpb.Empty, error) {
+					if err := authorityChecker(ctx, tt.expectedAuth); err != nil {
+						return nil, err
+					}
+					return &testpb.Empty{}, nil
+				},
+			}
+			serverOpt, dialOpt := tt.creds(t)
+			if err := ss.StartServer(serverOpt); err != nil {
+				t.Fatalf("Error starting endpoint server: %v", err)
+			}
+			defer ss.Stop()
+
+			cc, err := grpc.NewClient(ss.Address, dialOpt)
+			if err != nil {
+				t.Fatalf("grpc.NewClient(%q) = %v", ss.Address, err)
+			}
+			defer cc.Close()
+
+			ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+			defer cancel()
+			if _, err = testgrpc.NewTestServiceClient(cc).EmptyCall(ctx, &testpb.Empty{}, grpc.CallAuthority(tt.expectedAuth)); err != nil {
+				t.Fatalf("EmptyCall() rpc failed: %v", err)
+			}
+		})
+	}
+}
+
+// Tests the `grpc.CallAuthority` option with TLS credentials. This test verifies
+// that the RPC fails with `UNAVAILABLE` status code and doesn't reach the server
+// when an incorrect authority is used.
+func (s) TestIncorrectAuthorityWithTLS(t *testing.T) {
+	cert, err := tls.LoadX509KeyPair(testdata.Path("x509/server1_cert.pem"), testdata.Path("x509/server1_key.pem"))
+	if err != nil {
+		t.Fatalf("Failed to load key pair: %s", err)
+	}
+	creds, err := credentials.NewClientTLSFromFile(testdata.Path("x509/server_ca_cert.pem"), "x.test.example.com")
+	if err != nil {
+		t.Fatalf("Failed to create credentials %v", err)
+	}
+
+	tests := []struct {
+		name      string
+		authority string
+	}{
+		{
+			name:      "IncorrectAuthority",
+			authority: "auth.example.com",
+		},
+		{
+			name:      "IncorrectAuthorityWithPort",
+			authority: "auth.example.com:8443",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+
+			serverCalled := make(chan struct{})
+			ss := &stubserver.StubServer{
+				EmptyCallF: func(context.Context, *testpb.Empty) (*testpb.Empty, error) {
+					close(serverCalled)
+					return nil, nil
+				},
+			}
+			if err := ss.StartServer(grpc.Creds(credentials.NewServerTLSFromCert(&cert))); err != nil {
+				t.Fatalf("Error starting endpoint server: %v", err)
+			}
+			defer ss.Stop()
+			cc, err := grpc.NewClient(ss.Address, grpc.WithTransportCredentials(creds))
+			if err != nil {
+				t.Fatalf("grpc.NewClient(%q) = %v", ss.Address, err)
+			}
+			defer cc.Close()
+			ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+			defer cancel()
+			if _, err = testgrpc.NewTestServiceClient(cc).EmptyCall(ctx, &testpb.Empty{}, grpc.CallAuthority(tt.authority)); status.Code(err) != codes.Unavailable {
+				t.Fatalf("EmptyCall() returned status %v, want %v", status.Code(err), codes.Unavailable)
+			}
+			select {
+			case <-serverCalled:
+				t.Fatalf("Server handler should not have been called")
+			case <-time.After(defaultTestShortTimeout):
+			}
+		})
+	}
+}
+
+// testAuthInfoNoValidator implements only credentials.AuthInfo and not
+// credentials.AuthorityValidator.
+type testAuthInfoNoValidator struct{}
+
+// AuthType returns the authentication type.
+func (testAuthInfoNoValidator) AuthType() string {
+	return "test"
+}
+
+// testAuthInfoWithValidator implements both credentials.AuthInfo and
+// credentials.AuthorityValidator.
+type testAuthInfoWithValidator struct {
+	validAuthority string
+}
+
+// AuthType returns the authentication type.
+func (testAuthInfoWithValidator) AuthType() string {
+	return "test"
+}
+
+// ValidateAuthority implements credentials.AuthorityValidator.
+func (v testAuthInfoWithValidator) ValidateAuthority(authority string) error {
+	if authority == v.validAuthority {
+		return nil
+	}
+	return fmt.Errorf("invalid authority %q, want %q", authority, v.validAuthority)
+}
+
+// testCreds is a test TransportCredentials that can optionally support
+// authority validation.
+type testCreds struct {
+	authority string
+}
+
+// ClientHandshake performs the client-side handshake.
+func (c *testCreds) ClientHandshake(_ context.Context, _ string, rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	if c.authority != "" {
+		return rawConn, testAuthInfoWithValidator{validAuthority: c.authority}, nil
+	}
+	return rawConn, testAuthInfoNoValidator{}, nil
+}
+
+// ServerHandshake performs the server-side handshake.
+func (c *testCreds) ServerHandshake(rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	if c.authority != "" {
+		return rawConn, testAuthInfoWithValidator{validAuthority: c.authority}, nil
+	}
+	return rawConn, testAuthInfoNoValidator{}, nil
+}
+
+// Clone creates a copy of testCreds.
+func (c *testCreds) Clone() credentials.TransportCredentials {
+	return &testCreds{authority: c.authority}
+}
+
+// Info provides protocol information.
+func (c *testCreds) Info() credentials.ProtocolInfo {
+	return credentials.ProtocolInfo{}
+}
+
+// OverrideServerName overrides the server name used for verification.
+func (c *testCreds) OverrideServerName(string) error {
+	return nil
+}
+
+// TestAuthorityValidationFailureWithCustomCreds tests the `grpc.CallAuthority`
+// call option using custom credentials. It covers two failure scenarios:
+// - The credentials implement AuthorityValidator but authority used to override
+// is not valid.
+// - The credentials do not implement AuthorityValidator, but an authority
+// override is specified.
+// In both cases, the RPC is expected to fail with an `UNAVAILABLE` status code.
+func (s) TestAuthorityValidationFailureWithCustomCreds(t *testing.T) {
+	tests := []struct {
+		name      string
+		creds     credentials.TransportCredentials
+		authority string
+	}{
+		{
+			name:      "IncorrectAuthorityWithFakeCreds",
+			authority: "auth.example.com",
+			creds:     &testCreds{authority: "auth.test.example.com"},
+		},
+		{
+			name:      "FakeCredsWithNoAuthValidator",
+			creds:     &testCreds{},
+			authority: "auth.test.example.com",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			serverCalled := make(chan struct{})
+			ss := stubserver.StubServer{
+				EmptyCallF: func(context.Context, *testpb.Empty) (*testpb.Empty, error) {
+					close(serverCalled)
+					return nil, nil
+				},
+			}
+			if err := ss.StartServer(); err != nil {
+				t.Fatalf("Failed to start stub server: %v", err)
+			}
+			defer ss.Stop()
+
+			cc, err := grpc.NewClient(ss.Address, grpc.WithTransportCredentials(tt.creds))
+			if err != nil {
+				t.Fatalf("grpc.NewClient(%q) = %v", ss.Address, err)
+			}
+			defer cc.Close()
+
+			ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+			defer cancel()
+			if _, err = testgrpc.NewTestServiceClient(cc).EmptyCall(ctx, &testpb.Empty{}, grpc.CallAuthority(tt.authority)); status.Code(err) != codes.Unavailable {
+				t.Fatalf("EmptyCall() returned status %v, want %v", status.Code(err), codes.Unavailable)
+			}
+			select {
+			case <-serverCalled:
+				t.Fatalf("Server should not have been called")
+			case <-time.After(defaultTestShortTimeout):
+			}
+		})
+	}
+
+}
+
+// TestCorrectAuthorityWithCustomCreds tests the `grpc.CallAuthority` call
+// option using custom credentials. It verifies that the provided authority is
+// correctly propagated to the server when a correct authority is used.
+func (s) TestCorrectAuthorityWithCustomCreds(t *testing.T) {
+	const authority = "auth.test.example.com"
+	creds := &testCreds{authority: "auth.test.example.com"}
+	ss := stubserver.StubServer{
+		EmptyCallF: func(ctx context.Context, _ *testpb.Empty) (*testpb.Empty, error) {
+			if err := authorityChecker(ctx, authority); err != nil {
+				return nil, err
+			}
+			return &testpb.Empty{}, nil
+		},
+	}
+	if err := ss.StartServer(); err != nil {
+		t.Fatalf("Failed to start stub server: %v", err)
+	}
+	defer ss.Stop()
+
+	cc, err := grpc.NewClient(ss.Address, grpc.WithTransportCredentials(creds))
+	if err != nil {
+		t.Fatalf("grpc.NewClient(%q) = %v", ss.Address, err)
+	}
+	defer cc.Close()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+	if _, err = testgrpc.NewTestServiceClient(cc).EmptyCall(ctx, &testpb.Empty{}, grpc.CallAuthority(authority)); status.Code(err) != codes.OK {
+		t.Fatalf("EmptyCall() returned status %v, want %v", status.Code(err), codes.OK)
+	}
+}
+
+// TestAuthorityOverrideWithCertChain tests that the authority being used to
+// override per-RPC authority is validated against the leaf certificate only
+// and not against the intermediate certificates.
+func (s) TestAuthorityOverrideWithCertChain(t *testing.T) {
+	rootCert, certChain, leafKey := generateCertChain(t, "root.example.com", "intermediate.example.com", "*.leaf.example.com")
+
+	// Construct server credentials from leaf and intermediate certificates.
+	serverCert := tls.Certificate{
+		Certificate: [][]byte{certChain[0].Raw, certChain[1].Raw},
+		PrivateKey:  leafKey,
+	}
+	serverCreds := credentials.NewServerTLSFromCert(&serverCert)
+
+	// Create client credentials trusting the Root CA.
+	certPool := x509.NewCertPool()
+	certPool.AddCert(rootCert)
+	clientCreds := credentials.NewTLS(&tls.Config{
+		RootCAs:    certPool,
+		ServerName: "test1.leaf.example.com",
+	})
+
+	tests := []struct {
+		name      string
+		authority string
+		wantCode  codes.Code
+		wantErr   string
+	}{
+		{
+			name:      "AuthorityMatchesIntermediate",
+			authority: "intermediate.example.com",
+			wantCode:  codes.Unavailable,
+			wantErr:   "failed to validate authority",
+		},
+		{
+			name:      "AuthorityMatchesLeaf",
+			authority: "test2.leaf.example.com",
+			wantCode:  codes.OK,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Setup and start the stub server.
+			ss := &stubserver.StubServer{
+				EmptyCallF: func(ctx context.Context, _ *testpb.Empty) (*testpb.Empty, error) {
+					if err := authorityChecker(ctx, tt.authority); err != nil {
+						return nil, err
+					}
+					return &testpb.Empty{}, nil
+				},
+			}
+			if err := ss.StartServer(grpc.Creds(serverCreds)); err != nil {
+				t.Fatalf("failed to start server: %v", err)
+			}
+			defer ss.Stop()
+
+			cc, err := grpc.NewClient(ss.Address, grpc.WithTransportCredentials(clientCreds))
+			if err != nil {
+				t.Fatalf("grpc.NewClient(%q) = %v", ss.Address, err)
+			}
+			defer cc.Close()
+
+			ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+			defer cancel()
+
+			_, err = testgrpc.NewTestServiceClient(cc).EmptyCall(ctx, &testpb.Empty{}, grpc.CallAuthority(tt.authority))
+			if got := status.Code(err); got != tt.wantCode {
+				t.Fatalf("EmptyCall() with authority %q: got code %v, want %v", tt.authority, got, tt.wantCode)
+			}
+			if tt.wantErr != "" && (err == nil || !strings.Contains(err.Error(), tt.wantErr)) {
+				t.Fatalf("EmptyCall() with authority %q: expected error to contain %q, got %v", tt.authority, tt.wantErr, err)
+			}
+		})
+	}
+}
+
+// certConfig defines the configuration for generating a certificate.
+type certConfig struct {
+	commonName string
+	dnsNames   []string
+	isCA       bool
+	serial     int64
+	parentCert *x509.Certificate
+	parentKey  *rsa.PrivateKey
+}
+
+// createCertificate generates a certificate based on the provided certConfig.
+// It creates self-signed certificates if parentCert is nil otherwise it creates
+// certificates signed by a parent certificate.
+func createCertificate(t *testing.T, cfg certConfig) (*x509.Certificate, *rsa.PrivateKey) {
+	t.Helper()
+
+	key, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	now := time.Now()
+	tmpl := &x509.Certificate{
+		SerialNumber:          big.NewInt(cfg.serial),
+		Subject:               pkix.Name{CommonName: cfg.commonName},
+		DNSNames:              cfg.dnsNames,
+		NotBefore:             now.Add(-time.Hour),
+		NotAfter:              now.Add(time.Hour),
+		BasicConstraintsValid: true,
+		IsCA:                  cfg.isCA,
+	}
+
+	// If no parent is provided, the certificate is self-signed
+	signingCert := cfg.parentCert
+	signingKey := cfg.parentKey
+	if signingCert == nil {
+		signingCert = tmpl
+		signingKey = key
+	}
+
+	der, err := x509.CreateCertificate(rand.Reader, tmpl, signingCert, key.Public(), signingKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	cert, err := x509.ParseCertificate(der)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return cert, key
+}
+
+// generateCertChain creates a 3 certificate chain (Root -> Intermediate ->
+// Leaf). It returns the root certificate, a slice containing the leaf and
+// intermediate certificates in the order [leaf, intermediate], and the private
+// key for the leaf certificate.
+func generateCertChain(t *testing.T, rootName, interName, leafName string) (root *x509.Certificate, chain []*x509.Certificate, leafKey *rsa.PrivateKey) {
+	t.Helper()
+
+	rootCfg := certConfig{
+		commonName: rootName,
+		isCA:       true,
+	}
+	root, rootKey := createCertificate(t, rootCfg)
+
+	interCfg := certConfig{
+		commonName: interName,
+		dnsNames:   []string{interName},
+		isCA:       true,
+		serial:     2,
+		parentCert: root,
+		parentKey:  rootKey,
+	}
+	intermediate, interKey := createCertificate(t, interCfg)
+
+	leafCfg := certConfig{
+		commonName: leafName,
+		dnsNames:   []string{leafName},
+		isCA:       false,
+		serial:     3,
+		parentCert: intermediate,
+		parentKey:  interKey,
+	}
+	leaf, leafKey := createCertificate(t, leafCfg)
+
+	return root, []*x509.Certificate{leaf, intermediate}, leafKey
+}