credentials: move TLS implementation to a separate file (#3243)

credentials/credentials.go

@@ -24,17 +24,11 @@ package credentials // import "google.golang.org/grpc/credentials"
 
 import (
 	"context"
-	"crypto/tls"
-	"crypto/x509"
 	"errors"
-	"fmt"
-	"io/ioutil"
 	"net"
 
 	"github.com/golang/protobuf/proto"
-
+	"google.golang.org/grpc/internal"
-	"google.golang.org/grpc/credentials/internal"
-	ginternal "google.golang.org/grpc/internal"
 )
 
 // PerRPCCredentials defines the common interface for the credentials which need to
@@ -127,217 +121,6 @@ type Bundle interface {
 	NewWithMode(mode string) (Bundle, error)
 }
 
-// TLSInfo contains the auth information for a TLS authenticated connection.
-// It implements the AuthInfo interface.
-type TLSInfo struct {
-	State tls.ConnectionState
-}
-
-// AuthType returns the type of TLSInfo as a string.
-func (t TLSInfo) AuthType() string {
-	return "tls"
-}
-
-// GetSecurityValue returns security info requested by channelz.
-func (t TLSInfo) GetSecurityValue() ChannelzSecurityValue {
-	v := &TLSChannelzSecurityValue{
-		StandardName: cipherSuiteLookup[t.State.CipherSuite],
-	}
-	// Currently there's no way to get LocalCertificate info from tls package.
-	if len(t.State.PeerCertificates) > 0 {
-		v.RemoteCertificate = t.State.PeerCertificates[0].Raw
-	}
-	return v
-}
-
-// tlsCreds is the credentials required for authenticating a connection using TLS.
-type tlsCreds struct {
-	// TLS configuration
-	config *tls.Config
-}
-
-func (c tlsCreds) Info() ProtocolInfo {
-	return ProtocolInfo{
-		SecurityProtocol: "tls",
-		SecurityVersion:  "1.2",
-		ServerName:       c.config.ServerName,
-	}
-}
-
-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)
-	if cfg.ServerName == "" {
-		serverName, _, err := net.SplitHostPort(authority)
-		if err != nil {
-			// If the authority had no host port or if the authority cannot be parsed, use it as-is.
-			serverName = authority
-		}
-		cfg.ServerName = serverName
-	}
-	conn := tls.Client(rawConn, cfg)
-	errChannel := make(chan error, 1)
-	go func() {
-		errChannel <- conn.Handshake()
-	}()
-	select {
-	case err := <-errChannel:
-		if err != nil {
-			return nil, nil, err
-		}
-	case <-ctx.Done():
-		return nil, nil, ctx.Err()
-	}
-	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
-}
-
-func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {
-	conn := tls.Server(rawConn, c.config)
-	if err := conn.Handshake(); err != nil {
-		return nil, nil, err
-	}
-	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
-}
-
-func (c *tlsCreds) Clone() TransportCredentials {
-	return NewTLS(c.config)
-}
-
-func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
-	c.config.ServerName = serverNameOverride
-	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)
-	return tc
-}
-
-// NewClientTLSFromCert constructs TLS credentials from the input certificate for client.
-// serverNameOverride is for testing only. If set to a non empty string,
-// it will override the virtual host name of authority (e.g. :authority header field) in requests.
-func NewClientTLSFromCert(cp *x509.CertPool, serverNameOverride string) TransportCredentials {
-	return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp})
-}
-
-// NewClientTLSFromFile constructs TLS credentials from the input certificate file for client.
-// serverNameOverride is for testing only. If set to a non empty string,
-// it will override the virtual host name of authority (e.g. :authority header field) in requests.
-func NewClientTLSFromFile(certFile, serverNameOverride string) (TransportCredentials, error) {
-	b, err := ioutil.ReadFile(certFile)
-	if err != nil {
-		return nil, err
-	}
-	cp := x509.NewCertPool()
-	if !cp.AppendCertsFromPEM(b) {
-		return nil, fmt.Errorf("credentials: failed to append certificates")
-	}
-	return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp}), nil
-}
-
-// NewServerTLSFromCert constructs TLS credentials from the input certificate for server.
-func NewServerTLSFromCert(cert *tls.Certificate) TransportCredentials {
-	return NewTLS(&tls.Config{Certificates: []tls.Certificate{*cert}})
-}
-
-// NewServerTLSFromFile constructs TLS credentials from the input certificate file and key
-// file for server.
-func NewServerTLSFromFile(certFile, keyFile string) (TransportCredentials, error) {
-	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
-	if err != nil {
-		return nil, err
-	}
-	return NewTLS(&tls.Config{Certificates: []tls.Certificate{cert}}), nil
-}
-
-// ChannelzSecurityInfo defines the interface that security protocols should implement
-// in order to provide security info to channelz.
-type ChannelzSecurityInfo interface {
-	GetSecurityValue() ChannelzSecurityValue
-}
-
-// ChannelzSecurityValue defines the interface that GetSecurityValue() return value
-// should satisfy. This interface should only be satisfied by *TLSChannelzSecurityValue
-// and *OtherChannelzSecurityValue.
-type ChannelzSecurityValue interface {
-	isChannelzSecurityValue()
-}
-
-// TLSChannelzSecurityValue defines the struct that TLS protocol should return
-// from GetSecurityValue(), containing security info like cipher and certificate used.
-type TLSChannelzSecurityValue struct {
-	ChannelzSecurityValue
-	StandardName      string
-	LocalCertificate  []byte
-	RemoteCertificate []byte
-}
-
-// OtherChannelzSecurityValue defines the struct that non-TLS protocol should return
-// from GetSecurityValue(), which contains protocol specific security info. Note
-// the Value field will be sent to users of channelz requesting channel info, and
-// thus sensitive info should better be avoided.
-type OtherChannelzSecurityValue struct {
-	ChannelzSecurityValue
-	Name  string
-	Value proto.Message
-}
-
-var cipherSuiteLookup = map[uint16]string{
-	tls.TLS_RSA_WITH_RC4_128_SHA:                "TLS_RSA_WITH_RC4_128_SHA",
-	tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA:           "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
-	tls.TLS_RSA_WITH_AES_128_CBC_SHA:            "TLS_RSA_WITH_AES_128_CBC_SHA",
-	tls.TLS_RSA_WITH_AES_256_CBC_SHA:            "TLS_RSA_WITH_AES_256_CBC_SHA",
-	tls.TLS_RSA_WITH_AES_128_GCM_SHA256:         "TLS_RSA_WITH_AES_128_GCM_SHA256",
-	tls.TLS_RSA_WITH_AES_256_GCM_SHA384:         "TLS_RSA_WITH_AES_256_GCM_SHA384",
-	tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA:        "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA",
-	tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA:    "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
-	tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA:    "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA",
-	tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA:          "TLS_ECDHE_RSA_WITH_RC4_128_SHA",
-	tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA:     "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA",
-	tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA:      "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA",
-	tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA:      "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA",
-	tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:   "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
-	tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
-	tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:   "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
-	tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
-	tls.TLS_FALLBACK_SCSV:                       "TLS_FALLBACK_SCSV",
-	tls.TLS_RSA_WITH_AES_128_CBC_SHA256:         "TLS_RSA_WITH_AES_128_CBC_SHA256",
-	tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
-	tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256:   "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
-	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()
-}
-
 // RequestInfo contains request data attached to the context passed to GetRequestMetadata calls.
 //
 // This API is experimental.
@@ -358,7 +141,36 @@ func RequestInfoFromContext(ctx context.Context) (ri RequestInfo, ok bool) {
 }
 
 func init() {
-	ginternal.NewRequestInfoContext = func(ctx context.Context, ri RequestInfo) context.Context {
+	internal.NewRequestInfoContext = func(ctx context.Context, ri RequestInfo) context.Context {
 		return context.WithValue(ctx, requestInfoKey{}, ri)
 	}
 }
+
+// ChannelzSecurityInfo defines the interface that security protocols should implement
+// in order to provide security info to channelz.
+//
+// This API is experimental.
+type ChannelzSecurityInfo interface {
+	GetSecurityValue() ChannelzSecurityValue
+}
+
+// ChannelzSecurityValue defines the interface that GetSecurityValue() return value
+// should satisfy. This interface should only be satisfied by *TLSChannelzSecurityValue
+// and *OtherChannelzSecurityValue.
+//
+// This API is experimental.
+type ChannelzSecurityValue interface {
+	isChannelzSecurityValue()
+}
+
+// OtherChannelzSecurityValue defines the struct that non-TLS protocol should return
+// from GetSecurityValue(), which contains protocol specific security info. Note
+// the Value field will be sent to users of channelz requesting channel info, and
+// thus sensitive info should better be avoided.
+//
+// This API is experimental.
+type OtherChannelzSecurityValue struct {
+	ChannelzSecurityValue
+	Name  string
+	Value proto.Message
+}

credentials/tls.go

@@ -0,0 +1,220 @@
+/*
+ *
+ * Copyright 2014 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 (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"io/ioutil"
+	"net"
+
+	"google.golang.org/grpc/credentials/internal"
+)
+
+// TLSInfo contains the auth information for a TLS authenticated connection.
+// It implements the AuthInfo interface.
+type TLSInfo struct {
+	State tls.ConnectionState
+}
+
+// AuthType returns the type of TLSInfo as a string.
+func (t TLSInfo) AuthType() string {
+	return "tls"
+}
+
+// GetSecurityValue returns security info requested by channelz.
+func (t TLSInfo) GetSecurityValue() ChannelzSecurityValue {
+	v := &TLSChannelzSecurityValue{
+		StandardName: cipherSuiteLookup[t.State.CipherSuite],
+	}
+	// Currently there's no way to get LocalCertificate info from tls package.
+	if len(t.State.PeerCertificates) > 0 {
+		v.RemoteCertificate = t.State.PeerCertificates[0].Raw
+	}
+	return v
+}
+
+// tlsCreds is the credentials required for authenticating a connection using TLS.
+type tlsCreds struct {
+	// TLS configuration
+	config *tls.Config
+}
+
+func (c tlsCreds) Info() ProtocolInfo {
+	return ProtocolInfo{
+		SecurityProtocol: "tls",
+		SecurityVersion:  "1.2",
+		ServerName:       c.config.ServerName,
+	}
+}
+
+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)
+	if cfg.ServerName == "" {
+		serverName, _, err := net.SplitHostPort(authority)
+		if err != nil {
+			// If the authority had no host port or if the authority cannot be parsed, use it as-is.
+			serverName = authority
+		}
+		cfg.ServerName = serverName
+	}
+	conn := tls.Client(rawConn, cfg)
+	errChannel := make(chan error, 1)
+	go func() {
+		errChannel <- conn.Handshake()
+	}()
+	select {
+	case err := <-errChannel:
+		if err != nil {
+			return nil, nil, err
+		}
+	case <-ctx.Done():
+		return nil, nil, ctx.Err()
+	}
+	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
+}
+
+func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) {
+	conn := tls.Server(rawConn, c.config)
+	if err := conn.Handshake(); err != nil {
+		return nil, nil, err
+	}
+	return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState()}, nil
+}
+
+func (c *tlsCreds) Clone() TransportCredentials {
+	return NewTLS(c.config)
+}
+
+func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
+	c.config.ServerName = serverNameOverride
+	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)
+	return tc
+}
+
+// NewClientTLSFromCert constructs TLS credentials from the input certificate for client.
+// serverNameOverride is for testing only. If set to a non empty string,
+// it will override the virtual host name of authority (e.g. :authority header field) in requests.
+func NewClientTLSFromCert(cp *x509.CertPool, serverNameOverride string) TransportCredentials {
+	return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp})
+}
+
+// NewClientTLSFromFile constructs TLS credentials from the input certificate file for client.
+// serverNameOverride is for testing only. If set to a non empty string,
+// it will override the virtual host name of authority (e.g. :authority header field) in requests.
+func NewClientTLSFromFile(certFile, serverNameOverride string) (TransportCredentials, error) {
+	b, err := ioutil.ReadFile(certFile)
+	if err != nil {
+		return nil, err
+	}
+	cp := x509.NewCertPool()
+	if !cp.AppendCertsFromPEM(b) {
+		return nil, fmt.Errorf("credentials: failed to append certificates")
+	}
+	return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp}), nil
+}
+
+// NewServerTLSFromCert constructs TLS credentials from the input certificate for server.
+func NewServerTLSFromCert(cert *tls.Certificate) TransportCredentials {
+	return NewTLS(&tls.Config{Certificates: []tls.Certificate{*cert}})
+}
+
+// NewServerTLSFromFile constructs TLS credentials from the input certificate file and key
+// file for server.
+func NewServerTLSFromFile(certFile, keyFile string) (TransportCredentials, error) {
+	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
+	if err != nil {
+		return nil, err
+	}
+	return NewTLS(&tls.Config{Certificates: []tls.Certificate{cert}}), nil
+}
+
+// TLSChannelzSecurityValue defines the struct that TLS protocol should return
+// from GetSecurityValue(), containing security info like cipher and certificate used.
+//
+// This API is EXPERIMENTAL.
+type TLSChannelzSecurityValue struct {
+	ChannelzSecurityValue
+	StandardName      string
+	LocalCertificate  []byte
+	RemoteCertificate []byte
+}
+
+var cipherSuiteLookup = map[uint16]string{
+	tls.TLS_RSA_WITH_RC4_128_SHA:                "TLS_RSA_WITH_RC4_128_SHA",
+	tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA:           "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
+	tls.TLS_RSA_WITH_AES_128_CBC_SHA:            "TLS_RSA_WITH_AES_128_CBC_SHA",
+	tls.TLS_RSA_WITH_AES_256_CBC_SHA:            "TLS_RSA_WITH_AES_256_CBC_SHA",
+	tls.TLS_RSA_WITH_AES_128_GCM_SHA256:         "TLS_RSA_WITH_AES_128_GCM_SHA256",
+	tls.TLS_RSA_WITH_AES_256_GCM_SHA384:         "TLS_RSA_WITH_AES_256_GCM_SHA384",
+	tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA:        "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA:    "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA:    "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA",
+	tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA:          "TLS_ECDHE_RSA_WITH_RC4_128_SHA",
+	tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA:     "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA",
+	tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA:      "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA",
+	tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA:      "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA",
+	tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256:   "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
+	tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384:   "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
+	tls.TLS_FALLBACK_SCSV:                       "TLS_FALLBACK_SCSV",
+	tls.TLS_RSA_WITH_AES_128_CBC_SHA256:         "TLS_RSA_WITH_AES_128_CBC_SHA256",
+	tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
+	tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256:   "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
+	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()
+}

dialoptions.go

@@ -479,6 +479,8 @@ func WithAuthority(a string) DialOption {
 // WithChannelzParentID returns a DialOption that specifies the channelz ID of
 // current ClientConn's parent. This function is used in nested channel creation
 // (e.g. grpclb dial).
+//
+// This API is EXPERIMENTAL.
 func WithChannelzParentID(id int64) DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.channelzParentID = id