Dinesh Belwalkar | 396b652 | 2020-02-06 22:11:53 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2014 gRPC authors. |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | package credentials |
| 20 | |
| 21 | import ( |
| 22 | "context" |
| 23 | "crypto/tls" |
| 24 | "crypto/x509" |
| 25 | "fmt" |
| 26 | "io/ioutil" |
| 27 | "net" |
| 28 | |
| 29 | "google.golang.org/grpc/credentials/internal" |
| 30 | ) |
| 31 | |
| 32 | // TLSInfo contains the auth information for a TLS authenticated connection. |
| 33 | // It implements the AuthInfo interface. |
| 34 | type TLSInfo struct { |
| 35 | State tls.ConnectionState |
| 36 | CommonAuthInfo |
| 37 | } |
| 38 | |
| 39 | // AuthType returns the type of TLSInfo as a string. |
| 40 | func (t TLSInfo) AuthType() string { |
| 41 | return "tls" |
| 42 | } |
| 43 | |
| 44 | // GetSecurityValue returns security info requested by channelz. |
| 45 | func (t TLSInfo) GetSecurityValue() ChannelzSecurityValue { |
| 46 | v := &TLSChannelzSecurityValue{ |
| 47 | StandardName: cipherSuiteLookup[t.State.CipherSuite], |
| 48 | } |
| 49 | // Currently there's no way to get LocalCertificate info from tls package. |
| 50 | if len(t.State.PeerCertificates) > 0 { |
| 51 | v.RemoteCertificate = t.State.PeerCertificates[0].Raw |
| 52 | } |
| 53 | return v |
| 54 | } |
| 55 | |
| 56 | // tlsCreds is the credentials required for authenticating a connection using TLS. |
| 57 | type tlsCreds struct { |
| 58 | // TLS configuration |
| 59 | config *tls.Config |
| 60 | } |
| 61 | |
| 62 | func (c tlsCreds) Info() ProtocolInfo { |
| 63 | return ProtocolInfo{ |
| 64 | SecurityProtocol: "tls", |
| 65 | SecurityVersion: "1.2", |
| 66 | ServerName: c.config.ServerName, |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | func (c *tlsCreds) ClientHandshake(ctx context.Context, authority string, rawConn net.Conn) (_ net.Conn, _ AuthInfo, err error) { |
| 71 | // use local cfg to avoid clobbering ServerName if using multiple endpoints |
| 72 | cfg := cloneTLSConfig(c.config) |
| 73 | if cfg.ServerName == "" { |
| 74 | serverName, _, err := net.SplitHostPort(authority) |
| 75 | if err != nil { |
| 76 | // If the authority had no host port or if the authority cannot be parsed, use it as-is. |
| 77 | serverName = authority |
| 78 | } |
| 79 | cfg.ServerName = serverName |
| 80 | } |
| 81 | conn := tls.Client(rawConn, cfg) |
| 82 | errChannel := make(chan error, 1) |
| 83 | go func() { |
| 84 | errChannel <- conn.Handshake() |
| 85 | close(errChannel) |
| 86 | }() |
| 87 | select { |
| 88 | case err := <-errChannel: |
| 89 | if err != nil { |
| 90 | conn.Close() |
| 91 | return nil, nil, err |
| 92 | } |
| 93 | case <-ctx.Done(): |
| 94 | conn.Close() |
| 95 | return nil, nil, ctx.Err() |
| 96 | } |
| 97 | return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState(), CommonAuthInfo{PrivacyAndIntegrity}}, nil |
| 98 | } |
| 99 | |
| 100 | func (c *tlsCreds) ServerHandshake(rawConn net.Conn) (net.Conn, AuthInfo, error) { |
| 101 | conn := tls.Server(rawConn, c.config) |
| 102 | if err := conn.Handshake(); err != nil { |
| 103 | conn.Close() |
| 104 | return nil, nil, err |
| 105 | } |
| 106 | return internal.WrapSyscallConn(rawConn, conn), TLSInfo{conn.ConnectionState(), CommonAuthInfo{PrivacyAndIntegrity}}, nil |
| 107 | } |
| 108 | |
| 109 | func (c *tlsCreds) Clone() TransportCredentials { |
| 110 | return NewTLS(c.config) |
| 111 | } |
| 112 | |
| 113 | func (c *tlsCreds) OverrideServerName(serverNameOverride string) error { |
| 114 | c.config.ServerName = serverNameOverride |
| 115 | return nil |
| 116 | } |
| 117 | |
| 118 | const alpnProtoStrH2 = "h2" |
| 119 | |
| 120 | func appendH2ToNextProtos(ps []string) []string { |
| 121 | for _, p := range ps { |
| 122 | if p == alpnProtoStrH2 { |
| 123 | return ps |
| 124 | } |
| 125 | } |
| 126 | ret := make([]string, 0, len(ps)+1) |
| 127 | ret = append(ret, ps...) |
| 128 | return append(ret, alpnProtoStrH2) |
| 129 | } |
| 130 | |
| 131 | // NewTLS uses c to construct a TransportCredentials based on TLS. |
| 132 | func NewTLS(c *tls.Config) TransportCredentials { |
| 133 | tc := &tlsCreds{cloneTLSConfig(c)} |
| 134 | tc.config.NextProtos = appendH2ToNextProtos(tc.config.NextProtos) |
| 135 | return tc |
| 136 | } |
| 137 | |
| 138 | // NewClientTLSFromCert constructs TLS credentials from the input certificate for client. |
| 139 | // serverNameOverride is for testing only. If set to a non empty string, |
| 140 | // it will override the virtual host name of authority (e.g. :authority header field) in requests. |
| 141 | func NewClientTLSFromCert(cp *x509.CertPool, serverNameOverride string) TransportCredentials { |
| 142 | return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp}) |
| 143 | } |
| 144 | |
| 145 | // NewClientTLSFromFile constructs TLS credentials from the input certificate file for client. |
| 146 | // serverNameOverride is for testing only. If set to a non empty string, |
| 147 | // it will override the virtual host name of authority (e.g. :authority header field) in requests. |
| 148 | func NewClientTLSFromFile(certFile, serverNameOverride string) (TransportCredentials, error) { |
| 149 | b, err := ioutil.ReadFile(certFile) |
| 150 | if err != nil { |
| 151 | return nil, err |
| 152 | } |
| 153 | cp := x509.NewCertPool() |
| 154 | if !cp.AppendCertsFromPEM(b) { |
| 155 | return nil, fmt.Errorf("credentials: failed to append certificates") |
| 156 | } |
| 157 | return NewTLS(&tls.Config{ServerName: serverNameOverride, RootCAs: cp}), nil |
| 158 | } |
| 159 | |
| 160 | // NewServerTLSFromCert constructs TLS credentials from the input certificate for server. |
| 161 | func NewServerTLSFromCert(cert *tls.Certificate) TransportCredentials { |
| 162 | return NewTLS(&tls.Config{Certificates: []tls.Certificate{*cert}}) |
| 163 | } |
| 164 | |
| 165 | // NewServerTLSFromFile constructs TLS credentials from the input certificate file and key |
| 166 | // file for server. |
| 167 | func NewServerTLSFromFile(certFile, keyFile string) (TransportCredentials, error) { |
| 168 | cert, err := tls.LoadX509KeyPair(certFile, keyFile) |
| 169 | if err != nil { |
| 170 | return nil, err |
| 171 | } |
| 172 | return NewTLS(&tls.Config{Certificates: []tls.Certificate{cert}}), nil |
| 173 | } |
| 174 | |
| 175 | // TLSChannelzSecurityValue defines the struct that TLS protocol should return |
| 176 | // from GetSecurityValue(), containing security info like cipher and certificate used. |
| 177 | // |
| 178 | // This API is EXPERIMENTAL. |
| 179 | type TLSChannelzSecurityValue struct { |
| 180 | ChannelzSecurityValue |
| 181 | StandardName string |
| 182 | LocalCertificate []byte |
| 183 | RemoteCertificate []byte |
| 184 | } |
| 185 | |
| 186 | var cipherSuiteLookup = map[uint16]string{ |
| 187 | tls.TLS_RSA_WITH_RC4_128_SHA: "TLS_RSA_WITH_RC4_128_SHA", |
| 188 | tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA: "TLS_RSA_WITH_3DES_EDE_CBC_SHA", |
| 189 | tls.TLS_RSA_WITH_AES_128_CBC_SHA: "TLS_RSA_WITH_AES_128_CBC_SHA", |
| 190 | tls.TLS_RSA_WITH_AES_256_CBC_SHA: "TLS_RSA_WITH_AES_256_CBC_SHA", |
| 191 | tls.TLS_RSA_WITH_AES_128_GCM_SHA256: "TLS_RSA_WITH_AES_128_GCM_SHA256", |
| 192 | tls.TLS_RSA_WITH_AES_256_GCM_SHA384: "TLS_RSA_WITH_AES_256_GCM_SHA384", |
| 193 | tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA: "TLS_ECDHE_ECDSA_WITH_RC4_128_SHA", |
| 194 | tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA: "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA", |
| 195 | tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA: "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA", |
| 196 | tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA: "TLS_ECDHE_RSA_WITH_RC4_128_SHA", |
| 197 | tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA: "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA", |
| 198 | tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA: "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA", |
| 199 | tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA: "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA", |
| 200 | tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256: "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256", |
| 201 | tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", |
| 202 | tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384: "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384", |
| 203 | tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384: "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", |
| 204 | tls.TLS_FALLBACK_SCSV: "TLS_FALLBACK_SCSV", |
| 205 | tls.TLS_RSA_WITH_AES_128_CBC_SHA256: "TLS_RSA_WITH_AES_128_CBC_SHA256", |
| 206 | tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256: "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256", |
| 207 | tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256: "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256", |
| 208 | tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305: "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305", |
| 209 | tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305: "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305", |
| 210 | } |
| 211 | |
| 212 | // cloneTLSConfig returns a shallow clone of the exported |
| 213 | // fields of cfg, ignoring the unexported sync.Once, which |
| 214 | // contains a mutex and must not be copied. |
| 215 | // |
| 216 | // If cfg is nil, a new zero tls.Config is returned. |
| 217 | // |
| 218 | // TODO: inline this function if possible. |
| 219 | func cloneTLSConfig(cfg *tls.Config) *tls.Config { |
| 220 | if cfg == nil { |
| 221 | return &tls.Config{} |
| 222 | } |
| 223 | |
| 224 | return cfg.Clone() |
| 225 | } |