Source file src/github.com/tjfoc/gmsm/gmtls/gm_handshake_server.go

Documentation: github.com/tjfoc/gmsm/gmtls

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build single_cert
     6  
     7  package gmtls
     8  
     9  import (
    10  	"crypto"
    11  	"crypto/ecdsa"
    12  	"crypto/rsa"
    13  	"crypto/subtle"
    14  	"errors"
    15  	"fmt"
    16  	"io"
    17  	"sync/atomic"
    18  
    19  	"github.com/tjfoc/gmsm/sm2"
    20  	"github.com/tjfoc/gmsm/x509"
    21  )
    22  
    23  // serverHandshakeStateGM contains details of a server handshake in progress.
    24  // It's discarded once the handshake has completed.
    25  type serverHandshakeStateGM struct {
    26  	c                     *Conn
    27  	clientHello           *clientHelloMsg
    28  	hello                 *serverHelloMsg
    29  	suite                 *cipherSuite
    30  	sessionState          *sessionState
    31  	finishedHash          finishedHash
    32  	masterSecret          []byte
    33  	certsFromClient       [][]byte
    34  	cert                  *Certificate
    35  	cachedClientHelloInfo *ClientHelloInfo
    36  }
    37  
    38  // serverHandshake performs a TLS handshake as a server.
    39  func (c *Conn) serverHandshakeGM() error {
    40  	// If this is the first server handshake, we generate a random key to
    41  	// encrypt the tickets with.
    42  	c.config.serverInitOnce.Do(func() { c.config.serverInit(nil) })
    43  
    44  	hs := serverHandshakeStateGM{
    45  		c: c,
    46  	}
    47  	isResume, err := hs.readClientHello()
    48  	if err != nil {
    49  		return err
    50  	}
    51  
    52  	// For an overview of TLS handshaking, see https://tools.ietf.org/html/rfc5246#section-7.3
    53  	c.buffering = true
    54  	if isResume {
    55  		// The client has included a session ticket and so we do an abbreviated handshake.
    56  		if err := hs.doResumeHandshake(); err != nil {
    57  			return err
    58  		}
    59  		if err := hs.establishKeys(); err != nil {
    60  			return err
    61  		}
    62  		// ticketSupported is set in a resumption handshake if the
    63  		// ticket from the client was encrypted with an old session
    64  		// ticket key and thus a refreshed ticket should be sent.
    65  		if hs.hello.ticketSupported {
    66  			if err := hs.sendSessionTicket(); err != nil {
    67  				return err
    68  			}
    69  		}
    70  		if err := hs.sendFinished(c.serverFinished[:]); err != nil {
    71  			return err
    72  		}
    73  		if _, err := c.flush(); err != nil {
    74  			return err
    75  		}
    76  		c.clientFinishedIsFirst = false
    77  		if err := hs.readFinished(nil); err != nil {
    78  			return err
    79  		}
    80  		c.didResume = true
    81  	} else {
    82  		// The client didn't include a session ticket, or it wasn't
    83  		// valid so we do a full handshake.
    84  		if err := hs.doFullHandshake(); err != nil {
    85  			return err
    86  		}
    87  		if err := hs.establishKeys(); err != nil {
    88  			return err
    89  		}
    90  		if err := hs.readFinished(c.clientFinished[:]); err != nil {
    91  			return err
    92  		}
    93  		c.clientFinishedIsFirst = true
    94  		c.buffering = true
    95  		if err := hs.sendSessionTicket(); err != nil {
    96  			return err
    97  		}
    98  		if err := hs.sendFinished(nil); err != nil {
    99  			return err
   100  		}
   101  		if _, err := c.flush(); err != nil {
   102  			return err
   103  		}
   104  	}
   105  
   106  	c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random)
   107  	atomic.StoreUint32(&c.handshakeStatus, 1)
   108  
   109  	return nil
   110  }
   111  
   112  // readClientHello reads a ClientHello message from the client and decides
   113  // whether we will perform session resumption.
   114  func (hs *serverHandshakeStateGM) readClientHello() (isResume bool, err error) {
   115  	c := hs.c
   116  
   117  	msg, err := c.readHandshake()
   118  	if err != nil {
   119  		return false, err
   120  	}
   121  	var ok bool
   122  	hs.clientHello, ok = msg.(*clientHelloMsg)
   123  	if !ok {
   124  		c.sendAlert(alertUnexpectedMessage)
   125  		return false, unexpectedMessageError(hs.clientHello, msg)
   126  	}
   127  
   128  	if c.config.GetConfigForClient != nil {
   129  		if newConfig, err := c.config.GetConfigForClient(hs.clientHelloInfo()); err != nil {
   130  			c.sendAlert(alertInternalError)
   131  			return false, err
   132  		} else if newConfig != nil {
   133  			newConfig.serverInitOnce.Do(func() { newConfig.serverInit(c.config) })
   134  			c.config = newConfig
   135  		}
   136  	}
   137  
   138  	c.vers, ok = c.config.mutualVersion(hs.clientHello.vers)
   139  	if !ok {
   140  		c.sendAlert(alertProtocolVersion)
   141  		return false, fmt.Errorf("tls: client offered an unsupported, maximum protocol version of %x", hs.clientHello.vers)
   142  	}
   143  	c.haveVers = true
   144  
   145  	hs.hello = new(serverHelloMsg)
   146  
   147  	//supportedCurve := false
   148  	//	preferredCurves := c.config.curvePreferences()
   149  	//Curves:
   150  	//	for _, curve := range hs.clientHello.supportedCurves {
   151  	//		for _, supported := range preferredCurves {
   152  	//			if supported == curve {
   153  	//				supportedCurve = true
   154  	//				break Curves
   155  	//			}
   156  	//		}
   157  	//	}
   158  	//
   159  	//	supportedPointFormat := false
   160  	//	for _, pointFormat := range hs.clientHello.supportedPoints {
   161  	//		if pointFormat == pointFormatUncompressed {
   162  	//			supportedPointFormat = true
   163  	//			break
   164  	//		}
   165  	//	}
   166  	//	hs.ellipticOk = supportedCurve && supportedPointFormat
   167  
   168  	foundCompression := false
   169  	// We only support null compression, so check that the client offered it.
   170  	for _, compression := range hs.clientHello.compressionMethods {
   171  		if compression == compressionNone {
   172  			foundCompression = true
   173  			break
   174  		}
   175  	}
   176  
   177  	if !foundCompression {
   178  		c.sendAlert(alertHandshakeFailure)
   179  		return false, errors.New("tls: client does not support uncompressed connections")
   180  	}
   181  
   182  	hs.hello.vers = c.vers
   183  	hs.hello.random = make([]byte, 32)
   184  	_, err = io.ReadFull(c.config.rand(), hs.hello.random)
   185  	if err != nil {
   186  		c.sendAlert(alertInternalError)
   187  		return false, err
   188  	}
   189  
   190  	if len(hs.clientHello.secureRenegotiation) != 0 {
   191  		c.sendAlert(alertHandshakeFailure)
   192  		return false, errors.New("tls: initial handshake had non-empty renegotiation extension")
   193  	}
   194  
   195  	hs.hello.secureRenegotiationSupported = hs.clientHello.secureRenegotiationSupported
   196  	hs.hello.compressionMethod = compressionNone
   197  	if len(hs.clientHello.serverName) > 0 {
   198  		c.serverName = hs.clientHello.serverName
   199  	}
   200  
   201  	if len(hs.clientHello.alpnProtocols) > 0 {
   202  		if selectedProto, fallback := mutualProtocol(hs.clientHello.alpnProtocols, c.config.NextProtos); !fallback {
   203  			hs.hello.alpnProtocol = selectedProto
   204  			c.clientProtocol = selectedProto
   205  		}
   206  	} else {
   207  		// Although sending an empty NPN extension is reasonable, Firefox has
   208  		// had a bug around this. Best to send nothing at all if
   209  		// c.config.NextProtos is empty. See
   210  		// https://golang.org/issue/5445.
   211  		if hs.clientHello.nextProtoNeg && len(c.config.NextProtos) > 0 {
   212  			hs.hello.nextProtoNeg = true
   213  			hs.hello.nextProtos = c.config.NextProtos
   214  		}
   215  	}
   216  
   217  	hs.cert, err = c.config.getCertificate(hs.clientHelloInfo())
   218  	if err != nil {
   219  		c.sendAlert(alertInternalError)
   220  		return false, err
   221  	}
   222  	// GMT0024
   223  	// mod by syl just for test change two certs into one cert
   224  	//if len(hs.cert.Certificate) < 2 {
   225  	//	c.sendAlert(alertInternalError)
   226  	//	return false, fmt.Errorf("tls: amount of server certificates must be greater than 2, which will sign and encipher respectively")
   227  	//}
   228  	if len(hs.cert.Certificate) < 1 {
   229  		c.sendAlert(alertInternalError)
   230  		return false, fmt.Errorf("tls: amount of server certificates must be greater than 0")
   231  	}
   232  	if hs.clientHello.scts {
   233  		hs.hello.scts = hs.cert.SignedCertificateTimestamps
   234  	}
   235  
   236  	if hs.checkForResumption() {
   237  		return true, nil
   238  	}
   239  
   240  	var preferenceList, supportedList []uint16
   241  	if c.config.PreferServerCipherSuites {
   242  		preferenceList = getCipherSuites(c.config)
   243  		supportedList = hs.clientHello.cipherSuites
   244  	} else {
   245  		preferenceList = hs.clientHello.cipherSuites
   246  		supportedList = getCipherSuites(c.config)
   247  	}
   248  
   249  	for _, id := range preferenceList {
   250  		if hs.setCipherSuite(id, supportedList, c.vers) {
   251  			break
   252  		}
   253  	}
   254  
   255  	if hs.suite == nil {
   256  		c.sendAlert(alertHandshakeFailure)
   257  		return false, errors.New("tls: no cipher suite supported by both client and server")
   258  	}
   259  
   260  	// See https://tools.ietf.org/html/rfc7507.
   261  	for _, id := range hs.clientHello.cipherSuites {
   262  		if id == TLS_FALLBACK_SCSV {
   263  			// The client is doing a fallback connection.
   264  			if hs.clientHello.vers < c.config.maxVersion() {
   265  				c.sendAlert(alertInappropriateFallback)
   266  				return false, errors.New("tls: client using inappropriate protocol fallback")
   267  			}
   268  			break
   269  		}
   270  	}
   271  
   272  	return false, nil
   273  }
   274  
   275  // checkForResumption reports whether we should perform resumption on this connection.
   276  func (hs *serverHandshakeStateGM) checkForResumption() bool {
   277  	c := hs.c
   278  
   279  	if c.config.SessionTicketsDisabled {
   280  		return false
   281  	}
   282  
   283  	var ok bool
   284  	var sessionTicket = append([]uint8{}, hs.clientHello.sessionTicket...)
   285  	if hs.sessionState, ok = c.decryptTicket(sessionTicket); !ok {
   286  		return false
   287  	}
   288  
   289  	// Never resume a session for a different TLS version.
   290  	if c.vers != hs.sessionState.vers {
   291  		return false
   292  	}
   293  
   294  	cipherSuiteOk := false
   295  	// Check that the client is still offering the ciphersuite in the session.
   296  	for _, id := range hs.clientHello.cipherSuites {
   297  		if id == hs.sessionState.cipherSuite {
   298  			cipherSuiteOk = true
   299  			break
   300  		}
   301  	}
   302  	if !cipherSuiteOk {
   303  		return false
   304  	}
   305  
   306  	// Check that we also support the ciphersuite from the session.
   307  	if !hs.setCipherSuite(hs.sessionState.cipherSuite, c.config.cipherSuites(), hs.sessionState.vers) {
   308  		return false
   309  	}
   310  
   311  	sessionHasClientCerts := len(hs.sessionState.certificates) != 0
   312  	needClientCerts := c.config.ClientAuth == RequireAnyClientCert || c.config.ClientAuth == RequireAndVerifyClientCert
   313  	if needClientCerts && !sessionHasClientCerts {
   314  		return false
   315  	}
   316  	if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
   317  		return false
   318  	}
   319  
   320  	return true
   321  }
   322  
   323  func (hs *serverHandshakeStateGM) doResumeHandshake() error {
   324  	c := hs.c
   325  
   326  	hs.hello.cipherSuite = hs.suite.id
   327  	// We echo the client's session ID in the ServerHello to let it know
   328  	// that we're doing a resumption.
   329  	hs.hello.sessionId = hs.clientHello.sessionId
   330  	hs.hello.ticketSupported = hs.sessionState.usedOldKey
   331  	hs.finishedHash = newFinishedHash(c.vers, hs.suite)
   332  	hs.finishedHash.discardHandshakeBuffer()
   333  	hs.finishedHash.Write(hs.clientHello.marshal())
   334  	hs.finishedHash.Write(hs.hello.marshal())
   335  	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
   336  		return err
   337  	}
   338  
   339  	if len(hs.sessionState.certificates) > 0 {
   340  		if _, err := hs.processCertsFromClient(hs.sessionState.certificates); err != nil {
   341  			return err
   342  		}
   343  	}
   344  
   345  	hs.masterSecret = hs.sessionState.masterSecret
   346  
   347  	return nil
   348  }
   349  
   350  func (hs *serverHandshakeStateGM) doFullHandshake() error {
   351  	c := hs.c
   352  
   353  	if hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0 {
   354  		hs.hello.ocspStapling = true
   355  	}
   356  
   357  	hs.hello.ticketSupported = hs.clientHello.ticketSupported && !c.config.SessionTicketsDisabled
   358  	hs.hello.cipherSuite = hs.suite.id
   359  
   360  	hs.finishedHash = newFinishedHashGM(hs.suite)
   361  	if c.config.ClientAuth == NoClientCert {
   362  		// No need to keep a full record of the handshake if client
   363  		// certificates won't be used.
   364  		hs.finishedHash.discardHandshakeBuffer()
   365  	}
   366  	hs.finishedHash.Write(hs.clientHello.marshal())
   367  	hs.finishedHash.Write(hs.hello.marshal())
   368  	if _, err := c.writeRecord(recordTypeHandshake, hs.hello.marshal()); err != nil {
   369  		return err
   370  	}
   371  
   372  	certMsg := new(certificateMsg)
   373  	certMsg.certificates = hs.cert.Certificate
   374  	hs.finishedHash.Write(certMsg.marshal())
   375  	if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
   376  		return err
   377  	}
   378  
   379  	if hs.hello.ocspStapling {
   380  		certStatus := new(certificateStatusMsg)
   381  		certStatus.statusType = statusTypeOCSP
   382  		certStatus.response = hs.cert.OCSPStaple
   383  		hs.finishedHash.Write(certStatus.marshal())
   384  		if _, err := c.writeRecord(recordTypeHandshake, certStatus.marshal()); err != nil {
   385  			return err
   386  		}
   387  	}
   388  
   389  	keyAgreement := hs.suite.ka(c.vers)
   390  	skx, err := keyAgreement.generateServerKeyExchange(c.config, hs.cert, hs.cert, hs.clientHello, hs.hello)
   391  	if err != nil {
   392  		c.sendAlert(alertHandshakeFailure)
   393  		return err
   394  	}
   395  	if skx != nil {
   396  		hs.finishedHash.Write(skx.marshal())
   397  		if _, err := c.writeRecord(recordTypeHandshake, skx.marshal()); err != nil {
   398  			return err
   399  		}
   400  	}
   401  
   402  	if c.config.ClientAuth >= RequestClientCert {
   403  		// Request a client certificate
   404  		certReq := new(certificateRequestMsgGM)
   405  		certReq.certificateTypes = []byte{
   406  			byte(certTypeRSASign),
   407  			byte(certTypeECDSASign),
   408  		}
   409  		//if c.vers >= VersionTLS12 {
   410  		//	certReq.hasSignatureAndHash = true
   411  		//	certReq.supportedSignatureAlgorithms = supportedSignatureAlgorithms
   412  		//}
   413  
   414  		// An empty list of certificateAuthorities signals to
   415  		// the client that it may send any certificate in response
   416  		// to our request. When we know the CAs we trust, then
   417  		// we can send them down, so that the client can choose
   418  		// an appropriate certificate to give to us.
   419  		if c.config.ClientCAs != nil {
   420  			certReq.certificateAuthorities = c.config.ClientCAs.Subjects()
   421  		}
   422  		hs.finishedHash.Write(certReq.marshal())
   423  		if _, err := c.writeRecord(recordTypeHandshake, certReq.marshal()); err != nil {
   424  			return err
   425  		}
   426  	}
   427  
   428  	helloDone := new(serverHelloDoneMsg)
   429  	hs.finishedHash.Write(helloDone.marshal())
   430  	if _, err := c.writeRecord(recordTypeHandshake, helloDone.marshal()); err != nil {
   431  		return err
   432  	}
   433  
   434  	if _, err := c.flush(); err != nil {
   435  		return err
   436  	}
   437  
   438  	var pub crypto.PublicKey // public key for client auth, if any
   439  
   440  	msg, err := c.readHandshake()
   441  	if err != nil {
   442  		fmt.Println("readHandshake error:", err)
   443  		return err
   444  	}
   445  
   446  	var ok bool
   447  	// If we requested a client certificate, then the client must send a
   448  	// certificate message, even if it's empty.
   449  	if c.config.ClientAuth >= RequestClientCert {
   450  		if certMsg, ok = msg.(*certificateMsg); !ok {
   451  			c.sendAlert(alertUnexpectedMessage)
   452  			return unexpectedMessageError(certMsg, msg)
   453  		}
   454  		hs.finishedHash.Write(certMsg.marshal())
   455  
   456  		if len(certMsg.certificates) == 0 {
   457  			// The client didn't actually send a certificate
   458  			switch c.config.ClientAuth {
   459  			case RequireAnyClientCert, RequireAndVerifyClientCert:
   460  				c.sendAlert(alertBadCertificate)
   461  				return errors.New("tls: client didn't provide a certificate")
   462  			}
   463  		}
   464  
   465  		pub, err = hs.processCertsFromClient(certMsg.certificates)
   466  		if err != nil {
   467  			return err
   468  		}
   469  
   470  		msg, err = c.readHandshake()
   471  		if err != nil {
   472  			return err
   473  		}
   474  	}
   475  
   476  	// Get client key exchange
   477  	ckx, ok := msg.(*clientKeyExchangeMsg)
   478  	if !ok {
   479  		c.sendAlert(alertUnexpectedMessage)
   480  		return unexpectedMessageError(ckx, msg)
   481  	}
   482  	hs.finishedHash.Write(ckx.marshal())
   483  
   484  	preMasterSecret, err := keyAgreement.processClientKeyExchange(c.config, hs.cert, ckx, c.vers)
   485  	if err != nil {
   486  		c.sendAlert(alertHandshakeFailure)
   487  		return err
   488  	}
   489  	hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.clientHello.random, hs.hello.random)
   490  	if err := c.config.writeKeyLog(hs.clientHello.random, hs.masterSecret); err != nil {
   491  		c.sendAlert(alertInternalError)
   492  		return err
   493  	}
   494  
   495  	// If we received a client cert in response to our certificate request message,
   496  	// the client will send us a certificateVerifyMsg immediately after the
   497  	// clientKeyExchangeMsg. This message is a digest of all preceding
   498  	// handshake-layer messages that is signed using the private key corresponding
   499  	// to the client's certificate. This allows us to verify that the client is in
   500  	// possession of the private key of the certificate.
   501  	if len(c.peerCertificates) > 0 {
   502  		msg, err = c.readHandshake()
   503  		if err != nil {
   504  			return err
   505  		}
   506  		certVerify, ok := msg.(*certificateVerifyMsg)
   507  		if !ok {
   508  			c.sendAlert(alertUnexpectedMessage)
   509  			return unexpectedMessageError(certVerify, msg)
   510  		}
   511  
   512  		// Determine the signature type.
   513  		_, sigType, hashFunc, err := pickSignatureAlgorithm(pub, []SignatureScheme{certVerify.signatureAlgorithm}, supportedSignatureAlgorithms, c.vers)
   514  		if err != nil {
   515  			c.sendAlert(alertIllegalParameter)
   516  			return err
   517  		}
   518  
   519  		var digest []byte
   520  		if digest, err = hs.finishedHash.hashForClientCertificate(sigType, hashFunc, hs.masterSecret); err == nil {
   521  			err = verifyHandshakeSignature(sigType, pub, hashFunc, digest, certVerify.signature)
   522  		}
   523  		if err != nil {
   524  			c.sendAlert(alertBadCertificate)
   525  			return errors.New("tls: could not validate signature of connection nonces: " + err.Error())
   526  		}
   527  
   528  		hs.finishedHash.Write(certVerify.marshal())
   529  	}
   530  
   531  	hs.finishedHash.discardHandshakeBuffer()
   532  
   533  	return nil
   534  }
   535  
   536  func (hs *serverHandshakeStateGM) establishKeys() error {
   537  	c := hs.c
   538  
   539  	clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
   540  		keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.clientHello.random, hs.hello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
   541  
   542  	var clientCipher, serverCipher interface{}
   543  	var clientHash, serverHash macFunction
   544  
   545  	if hs.suite.aead == nil {
   546  		clientCipher = hs.suite.cipher(clientKey, clientIV, true /* for reading */)
   547  		clientHash = hs.suite.mac(c.vers, clientMAC)
   548  		serverCipher = hs.suite.cipher(serverKey, serverIV, false /* not for reading */)
   549  		serverHash = hs.suite.mac(c.vers, serverMAC)
   550  	} else {
   551  		clientCipher = hs.suite.aead(clientKey, clientIV)
   552  		serverCipher = hs.suite.aead(serverKey, serverIV)
   553  	}
   554  
   555  	c.in.prepareCipherSpec(c.vers, clientCipher, clientHash)
   556  	c.out.prepareCipherSpec(c.vers, serverCipher, serverHash)
   557  
   558  	return nil
   559  }
   560  
   561  func (hs *serverHandshakeStateGM) readFinished(out []byte) error {
   562  	c := hs.c
   563  
   564  	c.readRecord(recordTypeChangeCipherSpec)
   565  	if c.in.err != nil {
   566  		return c.in.err
   567  	}
   568  
   569  	if hs.hello.nextProtoNeg {
   570  		msg, err := c.readHandshake()
   571  		if err != nil {
   572  			return err
   573  		}
   574  		nextProto, ok := msg.(*nextProtoMsg)
   575  		if !ok {
   576  			c.sendAlert(alertUnexpectedMessage)
   577  			return unexpectedMessageError(nextProto, msg)
   578  		}
   579  		hs.finishedHash.Write(nextProto.marshal())
   580  		c.clientProtocol = nextProto.proto
   581  	}
   582  
   583  	msg, err := c.readHandshake()
   584  	if err != nil {
   585  		return err
   586  	}
   587  	clientFinished, ok := msg.(*finishedMsg)
   588  	if !ok {
   589  		c.sendAlert(alertUnexpectedMessage)
   590  		return unexpectedMessageError(clientFinished, msg)
   591  	}
   592  
   593  	verify := hs.finishedHash.clientSum(hs.masterSecret)
   594  	if len(verify) != len(clientFinished.verifyData) ||
   595  		subtle.ConstantTimeCompare(verify, clientFinished.verifyData) != 1 {
   596  		c.sendAlert(alertHandshakeFailure)
   597  		return errors.New("tls: client's Finished message is incorrect")
   598  	}
   599  
   600  	hs.finishedHash.Write(clientFinished.marshal())
   601  	copy(out, verify)
   602  	return nil
   603  }
   604  
   605  func (hs *serverHandshakeStateGM) sendSessionTicket() error {
   606  	if !hs.hello.ticketSupported {
   607  		return nil
   608  	}
   609  
   610  	c := hs.c
   611  	m := new(newSessionTicketMsg)
   612  
   613  	var err error
   614  	state := sessionState{
   615  		vers:         c.vers,
   616  		cipherSuite:  hs.suite.id,
   617  		masterSecret: hs.masterSecret,
   618  		certificates: hs.certsFromClient,
   619  	}
   620  	m.ticket, err = c.encryptTicket(&state)
   621  	if err != nil {
   622  		return err
   623  	}
   624  
   625  	hs.finishedHash.Write(m.marshal())
   626  	if _, err := c.writeRecord(recordTypeHandshake, m.marshal()); err != nil {
   627  		return err
   628  	}
   629  
   630  	return nil
   631  }
   632  
   633  func (hs *serverHandshakeStateGM) sendFinished(out []byte) error {
   634  	c := hs.c
   635  
   636  	if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
   637  		return err
   638  	}
   639  
   640  	finished := new(finishedMsg)
   641  	finished.verifyData = hs.finishedHash.serverSum(hs.masterSecret)
   642  	hs.finishedHash.Write(finished.marshal())
   643  	if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
   644  		return err
   645  	}
   646  
   647  	c.cipherSuite = hs.suite.id
   648  	copy(out, finished.verifyData)
   649  
   650  	return nil
   651  }
   652  
   653  // processCertsFromClient takes a chain of client certificates either from a
   654  // Certificates message or from a sessionState and verifies them. It returns
   655  // the public key of the leaf certificate.
   656  func (hs *serverHandshakeStateGM) processCertsFromClient(certificates [][]byte) (crypto.PublicKey, error) {
   657  	c := hs.c
   658  
   659  	hs.certsFromClient = certificates
   660  	certs := make([]*x509.Certificate, len(certificates))
   661  	var err error
   662  	for i, asn1Data := range certificates {
   663  		if certs[i], err = x509.ParseCertificate(asn1Data); err != nil {
   664  			c.sendAlert(alertBadCertificate)
   665  			return nil, errors.New("tls: failed to parse client certificate: " + err.Error())
   666  		}
   667  	}
   668  
   669  	if c.config.ClientAuth >= VerifyClientCertIfGiven && len(certs) > 0 {
   670  		opts := x509.VerifyOptions{
   671  			Roots:         c.config.ClientCAs,
   672  			CurrentTime:   c.config.time(),
   673  			Intermediates: x509.NewCertPool(),
   674  			KeyUsages:     []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
   675  		}
   676  
   677  		for _, cert := range certs[1:] {
   678  			opts.Intermediates.AddCert(cert)
   679  		}
   680  
   681  		chains, err := certs[0].Verify(opts)
   682  		if err != nil {
   683  			c.sendAlert(alertBadCertificate)
   684  			return nil, errors.New("tls: failed to verify client's certificate: " + err.Error())
   685  		}
   686  
   687  		c.verifiedChains = chains
   688  	}
   689  
   690  	if c.config.VerifyPeerCertificate != nil {
   691  		if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
   692  			c.sendAlert(alertBadCertificate)
   693  			return nil, err
   694  		}
   695  	}
   696  
   697  	if len(certs) == 0 {
   698  		return nil, nil
   699  	}
   700  
   701  	var pub crypto.PublicKey
   702  	switch key := certs[0].PublicKey.(type) {
   703  	case *ecdsa.PublicKey, *rsa.PublicKey, *sm2.PublicKey:
   704  		pub = key
   705  	default:
   706  		c.sendAlert(alertUnsupportedCertificate)
   707  		return nil, fmt.Errorf("tls: client's certificate contains an unsupported public key of type %T", certs[0].PublicKey)
   708  	}
   709  	c.peerCertificates = certs
   710  	return pub, nil
   711  }
   712  
   713  // setCipherSuite sets a cipherSuite with the given id as the serverHandshakeStateGM
   714  // suite if that cipher suite is acceptable to use.
   715  // It returns a bool indicating if the suite was set.
   716  func (hs *serverHandshakeStateGM) setCipherSuite(id uint16, supportedCipherSuites []uint16, version uint16) bool {
   717  	for _, supported := range supportedCipherSuites {
   718  		if id == supported {
   719  			var candidate *cipherSuite
   720  
   721  			for _, s := range gmCipherSuites {
   722  				if s.id == id {
   723  					candidate = s
   724  					break
   725  				}
   726  			}
   727  			if candidate == nil {
   728  				continue
   729  			}
   730  			if version < VersionTLS12 && candidate.flags&suiteTLS12 != 0 {
   731  				continue
   732  			}
   733  			hs.suite = candidate
   734  			return true
   735  		}
   736  	}
   737  	return false
   738  }
   739  
   740  func (hs *serverHandshakeStateGM) clientHelloInfo() *ClientHelloInfo {
   741  	if hs.cachedClientHelloInfo != nil {
   742  		return hs.cachedClientHelloInfo
   743  	}
   744  
   745  	var supportedVersions []uint16
   746  	if hs.clientHello.vers > VersionTLS12 {
   747  		supportedVersions = suppVersArray[:]
   748  	} else if hs.clientHello.vers >= VersionSSL30 {
   749  		supportedVersions = suppVersArray[VersionTLS12-hs.clientHello.vers:]
   750  	}
   751  
   752  	hs.cachedClientHelloInfo = &ClientHelloInfo{
   753  		CipherSuites:      hs.clientHello.cipherSuites,
   754  		ServerName:        hs.clientHello.serverName,
   755  		SupportedCurves:   hs.clientHello.supportedCurves,
   756  		SupportedPoints:   hs.clientHello.supportedPoints,
   757  		SignatureSchemes:  hs.clientHello.supportedSignatureAlgorithms,
   758  		SupportedProtos:   hs.clientHello.alpnProtocols,
   759  		SupportedVersions: supportedVersions,
   760  		Conn:              hs.c.conn,
   761  	}
   762  
   763  	return hs.cachedClientHelloInfo
   764  }
   765  

View as plain text