credentials: Migrate helper functions to /internal/credentials for future cleanup (#3780)

* credentials: migrate functions in credentials/internal to internal/credentials to be used for other modules

credentials/credentials_test.go

@@ -22,7 +22,6 @@ import (
 	"context"
 	"crypto/tls"
 	"net"
-	"reflect"
 	"strings"
 	"testing"
 
@@ -326,39 +325,3 @@ func tlsClientHandshake(conn net.Conn, _ string) (AuthInfo, error) {
 	}
 	return TLSInfo{State: clientConn.ConnectionState(), CommonAuthInfo: CommonAuthInfo{SecurityLevel: PrivacyAndIntegrity}}, nil
 }
-
-func (s) TestAppendH2ToNextProtos(t *testing.T) {
-	tests := []struct {
-		name string
-		ps   []string
-		want []string
-	}{
-		{
-			name: "empty",
-			ps:   nil,
-			want: []string{"h2"},
-		},
-		{
-			name: "only h2",
-			ps:   []string{"h2"},
-			want: []string{"h2"},
-		},
-		{
-			name: "with h2",
-			ps:   []string{"alpn", "h2"},
-			want: []string{"alpn", "h2"},
-		},
-		{
-			name: "no h2",
-			ps:   []string{"alpn"},
-			want: []string{"alpn", "h2"},
-		},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			if got := appendH2ToNextProtos(tt.ps); !reflect.DeepEqual(got, tt.want) {
-				t.Errorf("appendH2ToNextProtos() = %v, want %v", got, tt.want)
-			}
-		})
-	}
-}

credentials/tls.go

@@ -27,7 +27,6 @@ import (
 	"net"
 	"net/url"
 
-	"google.golang.org/grpc/credentials/internal"
 	credinternal "google.golang.org/grpc/internal/credentials"
 )
 
@@ -73,7 +72,7 @@ func (c tlsCreds) Info() ProtocolInfo {
 
 func (c *tlsCreds) ClientHandshake(ctx context.Context, authority string, rawConn net.Conn) (_ net.Conn, _ AuthInfo, err error) {
 	// use local cfg to avoid clobbering ServerName if using multiple endpoints
-	cfg := cloneTLSConfig(c.config)
+	cfg := credinternal.CloneTLSConfig(c.config)
 	if cfg.ServerName == "" {
 		serverName, _, err := net.SplitHostPort(authority)
 		if err != nil {
@@ -108,7 +107,7 @@ func (c *tlsCreds) ClientHandshake(ctx context.Context, authority string, rawCon
 	if id != nil {
 		tlsInfo.SPIFFEID = id
 	}
-	return internal.WrapSyscallConn(rawConn, conn), tlsInfo, nil
+	return credinternal.WrapSyscallConn(rawConn, conn), tlsInfo, nil
 }
 
 func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {
@@ -127,7 +126,7 @@ func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error)
 	if id != nil {
 		tlsInfo.SPIFFEID = id
 	}
-	return internal.WrapSyscallConn(rawConn, conn), tlsInfo, nil
+	return credinternal.WrapSyscallConn(rawConn, conn), tlsInfo, nil
 }
 
 func (c *tlsCreds) Clone() TransportCredentials {
@@ -139,23 +138,10 @@ func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
 	return nil
 }
 
-const alpnProtoStrH2 = "h2"
-
-func appendH2ToNextProtos(ps []string) []string {
-	for _, p := range ps {
-		if p == alpnProtoStrH2 {
-			return ps
-		}
-	}
-	ret := make([]string, 0, len(ps)+1)
-	ret = append(ret, ps...)
-	return append(ret, alpnProtoStrH2)
-}
-
 // NewTLS uses c to construct a TransportCredentials based on TLS.
 func NewTLS(c *tls.Config) TransportCredentials {
-	tc := &tlsCreds{cloneTLSConfig(c)}
-	tc.config.NextProtos = appendH2ToNextProtos(tc.config.NextProtos)
+	tc := &tlsCreds{credinternal.CloneTLSConfig(c)}
+	tc.config.NextProtos = credinternal.AppendH2ToNextProtos(tc.config.NextProtos)
 	return tc
 }
 
@@ -242,18 +228,3 @@ var cipherSuiteLookup = map[uint16]string{
 	tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305:    "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305",
 	tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305:  "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305",
 }
-
-// cloneTLSConfig returns a shallow clone of the exported
-// fields of cfg, ignoring the unexported sync.Once, which
-// contains a mutex and must not be copied.
-//
-// If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO: inline this function if possible.
-func cloneTLSConfig(cfg *tls.Config) *tls.Config {
-	if cfg == nil {
-		return &tls.Config{}
-	}
-
-	return cfg.Clone()
-}

internal/credentials/syscallconn.go

@@ -16,8 +16,7 @@
  *
  */
 
-// Package internal contains credentials-internal code.
-package internal
+package credentials
 
 import (
 	"net"

internal/credentials/syscallconn_test.go

@@ -16,29 +16,14 @@
  *
  */
 
-package internal_test
+package credentials
 
 import (
 	"net"
 	"syscall"
 	"testing"
-
-	"google.golang.org/grpc/credentials/internal"
-	"google.golang.org/grpc/internal/grpctest"
 )
 
-type s struct {
-	grpctest.Tester
-}
-
-func Test(t *testing.T) {
-	grpctest.RunSubTests(t, s{})
-}
-
-type syscallConn struct {
-	net.Conn
-}
-
 func (*syscallConn) SyscallConn() (syscall.RawConn, error) {
 	return nil, nil
 }
@@ -51,7 +36,7 @@ func (s) TestWrapSyscallConn(t *testing.T) {
 	sc := &syscallConn{}
 	nsc := &nonSyscallConn{}
 
-	wrapConn := internal.WrapSyscallConn(sc, nsc)
+	wrapConn := WrapSyscallConn(sc, nsc)
 	if _, ok := wrapConn.(syscall.Conn); !ok {
 		t.Errorf("returned conn (type %T) doesn't implement syscall.Conn, want implement", wrapConn)
 	}
@@ -61,7 +46,7 @@ func (s) TestWrapSyscallConnNoWrap(t *testing.T) {
 	nscRaw := &nonSyscallConn{}
 	nsc := &nonSyscallConn{}
 
-	wrapConn := internal.WrapSyscallConn(nscRaw, nsc)
+	wrapConn := WrapSyscallConn(nscRaw, nsc)
 	if _, ok := wrapConn.(syscall.Conn); ok {
 		t.Errorf("returned conn (type %T) implements syscall.Conn, want not implement", wrapConn)
 	}

internal/credentials/util.go

@@ -0,0 +1,50 @@
+/*
+ *
+ * Copyright 2020 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
+
+import "crypto/tls"
+
+const alpnProtoStrH2 = "h2"
+
+// AppendH2ToNextProtos appends h2 to next protos.
+func AppendH2ToNextProtos(ps []string) []string {
+	for _, p := range ps {
+		if p == alpnProtoStrH2 {
+			return ps
+		}
+	}
+	ret := make([]string, 0, len(ps)+1)
+	ret = append(ret, ps...)
+	return append(ret, alpnProtoStrH2)
+}
+
+// CloneTLSConfig returns a shallow clone of the exported
+// fields of cfg, ignoring the unexported sync.Once, which
+// contains a mutex and must not be copied.
+//
+// If cfg is nil, a new zero tls.Config is returned.
+//
+// TODO: inline this function if possible.
+func CloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+
+	return cfg.Clone()
+}

internal/credentials/util_test.go

@@ -0,0 +1,60 @@
+/*
+ *
+ * Copyright 2020 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
+
+import (
+	"reflect"
+	"testing"
+)
+
+func (s) TestAppendH2ToNextProtos(t *testing.T) {
+	tests := []struct {
+		name string
+		ps   []string
+		want []string
+	}{
+		{
+			name: "empty",
+			ps:   nil,
+			want: []string{"h2"},
+		},
+		{
+			name: "only h2",
+			ps:   []string{"h2"},
+			want: []string{"h2"},
+		},
+		{
+			name: "with h2",
+			ps:   []string{"alpn", "h2"},
+			want: []string{"alpn", "h2"},
+		},
+		{
+			name: "no h2",
+			ps:   []string{"alpn"},
+			want: []string{"alpn", "h2"},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := AppendH2ToNextProtos(tt.ps); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("AppendH2ToNextProtos() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}