--- /dev/null
+/*
+ *
+ * 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 implements various credentials supported by gRPC library,
+// which encapsulate all the state needed by a client to authenticate with a
+// server and make various assertions, e.g., about the client's identity, role,
+// or whether it is authorized to make a particular call.
+package credentials // import "google.golang.org/grpc/credentials"
+
+import (
+ "crypto/tls"
+ "crypto/x509"
+ "errors"
+ "fmt"
+ "io/ioutil"
+ "net"
+ "strings"
+
+ "golang.org/x/net/context"
+)
+
+// alpnProtoStr are the specified application level protocols for gRPC.
+var alpnProtoStr = []string{"h2"}
+
+// PerRPCCredentials defines the common interface for the credentials which need to
+// attach security information to every RPC (e.g., oauth2).
+type PerRPCCredentials interface {
+ // GetRequestMetadata gets the current request metadata, refreshing
+ // tokens if required. This should be called by the transport layer on
+ // each request, and the data should be populated in headers or other
+ // context. uri is the URI of the entry point for the request. When
+ // supported by the underlying implementation, ctx can be used for
+ // timeout and cancellation.
+ // TODO(zhaoq): Define the set of the qualified keys instead of leaving
+ // it as an arbitrary string.
+ GetRequestMetadata(ctx context.Context, uri ...string) (map[string]string, error)
+ // RequireTransportSecurity indicates whether the credentials requires
+ // transport security.
+ RequireTransportSecurity() bool
+}
+
+// ProtocolInfo provides information regarding the gRPC wire protocol version,
+// security protocol, security protocol version in use, server name, etc.
+type ProtocolInfo struct {
+ // ProtocolVersion is the gRPC wire protocol version.
+ ProtocolVersion string
+ // SecurityProtocol is the security protocol in use.
+ SecurityProtocol string
+ // SecurityVersion is the security protocol version.
+ SecurityVersion string
+ // ServerName is the user-configured server name.
+ ServerName string
+}
+
+// AuthInfo defines the common interface for the auth information the users are interested in.
+type AuthInfo interface {
+ AuthType() string
+}
+
+// ErrConnDispatched indicates that rawConn has been dispatched out of gRPC
+// and the caller should not close rawConn.
+var ErrConnDispatched = errors.New("credentials: rawConn is dispatched out of gRPC")
+
+// TransportCredentials defines the common interface for all the live gRPC wire
+// protocols and supported transport security protocols (e.g., TLS, SSL).
+type TransportCredentials interface {
+ // ClientHandshake does the authentication handshake specified by the corresponding
+ // authentication protocol on rawConn for clients. It returns the authenticated
+ // connection and the corresponding auth information about the connection.
+ // Implementations must use the provided context to implement timely cancellation.
+ // gRPC will try to reconnect if the error returned is a temporary error
+ // (io.EOF, context.DeadlineExceeded or err.Temporary() == true).
+ // If the returned error is a wrapper error, implementations should make sure that
+ // the error implements Temporary() to have the correct retry behaviors.
+ ClientHandshake(context.Context, string, net.Conn) (net.Conn, AuthInfo, error)
+ // ServerHandshake does the authentication handshake for servers. It returns
+ // the authenticated connection and the corresponding auth information about
+ // the connection.
+ ServerHandshake(net.Conn) (net.Conn, AuthInfo, error)
+ // Info provides the ProtocolInfo of this TransportCredentials.
+ Info() ProtocolInfo
+ // Clone makes a copy of this TransportCredentials.
+ Clone() TransportCredentials
+ // OverrideServerName overrides the server name used to verify the hostname on the returned certificates from the server.
+ // gRPC internals also use it to override the virtual hosting name if it is set.
+ // It must be called before dialing. Currently, this is only used by grpclb.
+ OverrideServerName(string) 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"
+}
+
+// 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 == "" {
+ colonPos := strings.LastIndex(authority, ":")
+ if colonPos == -1 {
+ colonPos = len(authority)
+ }
+ cfg.ServerName = authority[:colonPos]
+ }
+ 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 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 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
+}
+
+// NewTLS uses c to construct a TransportCredentials based on TLS.
+func NewTLS(c *tls.Config) TransportCredentials {
+ tc := &tlsCreds{cloneTLSConfig(c)}
+ tc.config.NextProtos = alpnProtoStr
+ 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
+}
OSDN Git Service
