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path: root/src/pkg/crypto/tls/handshake_server.go
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Diffstat (limited to 'src/pkg/crypto/tls/handshake_server.go')
-rw-r--r--src/pkg/crypto/tls/handshake_server.go654
1 files changed, 0 insertions, 654 deletions
diff --git a/src/pkg/crypto/tls/handshake_server.go b/src/pkg/crypto/tls/handshake_server.go
deleted file mode 100644
index dff6fd9ad..000000000
--- a/src/pkg/crypto/tls/handshake_server.go
+++ /dev/null
@@ -1,654 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package tls
-
-import (
- "crypto"
- "crypto/ecdsa"
- "crypto/rsa"
- "crypto/subtle"
- "crypto/x509"
- "encoding/asn1"
- "errors"
- "fmt"
- "io"
-)
-
-// serverHandshakeState contains details of a server handshake in progress.
-// It's discarded once the handshake has completed.
-type serverHandshakeState struct {
- c *Conn
- clientHello *clientHelloMsg
- hello *serverHelloMsg
- suite *cipherSuite
- ellipticOk bool
- ecdsaOk bool
- sessionState *sessionState
- finishedHash finishedHash
- masterSecret []byte
- certsFromClient [][]byte
- cert *Certificate
-}
-
-// serverHandshake performs a TLS handshake as a server.
-func (c *Conn) serverHandshake() error {
- config := c.config
-
- // If this is the first server handshake, we generate a random key to
- // encrypt the tickets with.
- config.serverInitOnce.Do(config.serverInit)
-
- hs := serverHandshakeState{
- c: c,
- }
- isResume, err := hs.readClientHello()
- if err != nil {
- return err
- }
-
- // For an overview of TLS handshaking, see https://tools.ietf.org/html/rfc5246#section-7.3
- if isResume {
- // The client has included a session ticket and so we do an abbreviated handshake.
- if err := hs.doResumeHandshake(); err != nil {
- return err
- }
- if err := hs.establishKeys(); err != nil {
- return err
- }
- if err := hs.sendFinished(); err != nil {
- return err
- }
- if err := hs.readFinished(); err != nil {
- return err
- }
- c.didResume = true
- } else {
- // The client didn't include a session ticket, or it wasn't
- // valid so we do a full handshake.
- if err := hs.doFullHandshake(); err != nil {
- return err
- }
- if err := hs.establishKeys(); err != nil {
- return err
- }
- if err := hs.readFinished(); err != nil {
- return err
- }
- if err := hs.sendSessionTicket(); err != nil {
- return err
- }
- if err := hs.sendFinished(); err != nil {
- return err
- }
- }
- c.handshakeComplete = true
-
- return nil
-}
-
-// readClientHello reads a ClientHello message from the client and decides
-// whether we will perform session resumption.
-func (hs *serverHandshakeState) readClientHello() (isResume bool, err error) {
- config := hs.c.config
- c := hs.c
-
- msg, err := c.readHandshake()
- if err != nil {
- return false, err
- }
- var ok bool
- hs.clientHello, ok = msg.(*clientHelloMsg)
- if !ok {
- c.sendAlert(alertUnexpectedMessage)
- return false, unexpectedMessageError(hs.clientHello, msg)
- }
- c.vers, ok = config.mutualVersion(hs.clientHello.vers)
- if !ok {
- c.sendAlert(alertProtocolVersion)
- return false, fmt.Errorf("tls: client offered an unsupported, maximum protocol version of %x", hs.clientHello.vers)
- }
- c.haveVers = true
-
- hs.finishedHash = newFinishedHash(c.vers)
- hs.finishedHash.Write(hs.clientHello.marshal())
-
- hs.hello = new(serverHelloMsg)
-
- supportedCurve := false
- preferredCurves := config.curvePreferences()
-Curves:
- for _, curve := range hs.clientHello.supportedCurves {
- for _, supported := range preferredCurves {
- if supported == curve {
- supportedCurve = true
- break Curves
- }
- }
- }
-
- supportedPointFormat := false
- for _, pointFormat := range hs.clientHello.supportedPoints {
- if pointFormat == pointFormatUncompressed {
- supportedPointFormat = true
- break
- }
- }
- hs.ellipticOk = supportedCurve && supportedPointFormat
-
- foundCompression := false
- // We only support null compression, so check that the client offered it.
- for _, compression := range hs.clientHello.compressionMethods {
- if compression == compressionNone {
- foundCompression = true
- break
- }
- }
-
- if !foundCompression {
- c.sendAlert(alertHandshakeFailure)
- return false, errors.New("tls: client does not support uncompressed connections")
- }
-
- hs.hello.vers = c.vers
- hs.hello.random = make([]byte, 32)
- _, err = io.ReadFull(config.rand(), hs.hello.random)
- if err != nil {
- c.sendAlert(alertInternalError)
- return false, err
- }
- hs.hello.secureRenegotiation = hs.clientHello.secureRenegotiation
- hs.hello.compressionMethod = compressionNone
- if len(hs.clientHello.serverName) > 0 {
- c.serverName = hs.clientHello.serverName
- }
- // Although sending an empty NPN extension is reasonable, Firefox has
- // had a bug around this. Best to send nothing at all if
- // config.NextProtos is empty. See
- // https://code.google.com/p/go/issues/detail?id=5445.
- if hs.clientHello.nextProtoNeg && len(config.NextProtos) > 0 {
- hs.hello.nextProtoNeg = true
- hs.hello.nextProtos = config.NextProtos
- }
-
- if len(config.Certificates) == 0 {
- c.sendAlert(alertInternalError)
- return false, errors.New("tls: no certificates configured")
- }
- hs.cert = &config.Certificates[0]
- if len(hs.clientHello.serverName) > 0 {
- hs.cert = config.getCertificateForName(hs.clientHello.serverName)
- }
-
- _, hs.ecdsaOk = hs.cert.PrivateKey.(*ecdsa.PrivateKey)
-
- if hs.checkForResumption() {
- return true, nil
- }
-
- var preferenceList, supportedList []uint16
- if c.config.PreferServerCipherSuites {
- preferenceList = c.config.cipherSuites()
- supportedList = hs.clientHello.cipherSuites
- } else {
- preferenceList = hs.clientHello.cipherSuites
- supportedList = c.config.cipherSuites()
- }
-
- for _, id := range preferenceList {
- if hs.suite = c.tryCipherSuite(id, supportedList, c.vers, hs.ellipticOk, hs.ecdsaOk); hs.suite != nil {
- break
- }
- }
-
- if hs.suite == nil {
- c.sendAlert(alertHandshakeFailure)
- return false, errors.New("tls: no cipher suite supported by both client and server")
- }
-
- return false, nil
-}
-
-// checkForResumption returns true if we should perform resumption on this connection.
-func (hs *serverHandshakeState) checkForResumption() bool {
- c := hs.c
-
- if c.config.SessionTicketsDisabled {
- return false
- }
-
- var ok bool
- if hs.sessionState, ok = c.decryptTicket(hs.clientHello.sessionTicket); !ok {
- return false
- }
-
- if hs.sessionState.vers > hs.clientHello.vers {
- return false
- }
- if vers, ok := c.config.mutualVersion(hs.sessionState.vers); !ok || vers != hs.sessionState.vers {
- return false
- }
-
- cipherSuiteOk := false
- // Check that the client is still offering the ciphersuite in the session.
- for _, id := range hs.clientHello.cipherSuites {
- if id == hs.sessionState.cipherSuite {
- cipherSuiteOk = true
- break
- }
- }
- if !cipherSuiteOk {
- return false
- }
-
- // Check that we also support the ciphersuite from the session.
- hs.suite = c.tryCipherSuite(hs.sessionState.cipherSuite, c.config.cipherSuites(), hs.sessionState.vers, hs.ellipticOk, hs.ecdsaOk)
- if hs.suite == nil {
- return false
- }
-
- sessionHasClientCerts := len(hs.sessionState.certificates) != 0
- needClientCerts := c.config.ClientAuth == RequireAnyClientCert || c.config.ClientAuth == RequireAndVerifyClientCert
- if needClientCerts && !sessionHasClientCerts {
- return false
- }
- if sessionHasClientCerts && c.config.ClientAuth == NoClientCert {
- return false
- }
-
- return true
-}
-
-func (hs *serverHandshakeState) doResumeHandshake() error {
- c := hs.c
-
- hs.hello.cipherSuite = hs.suite.id
- // We echo the client's session ID in the ServerHello to let it know
- // that we're doing a resumption.
- hs.hello.sessionId = hs.clientHello.sessionId
- hs.finishedHash.Write(hs.hello.marshal())
- c.writeRecord(recordTypeHandshake, hs.hello.marshal())
-
- if len(hs.sessionState.certificates) > 0 {
- if _, err := hs.processCertsFromClient(hs.sessionState.certificates); err != nil {
- return err
- }
- }
-
- hs.masterSecret = hs.sessionState.masterSecret
-
- return nil
-}
-
-func (hs *serverHandshakeState) doFullHandshake() error {
- config := hs.c.config
- c := hs.c
-
- if hs.clientHello.ocspStapling && len(hs.cert.OCSPStaple) > 0 {
- hs.hello.ocspStapling = true
- }
-
- hs.hello.ticketSupported = hs.clientHello.ticketSupported && !config.SessionTicketsDisabled
- hs.hello.cipherSuite = hs.suite.id
- hs.finishedHash.Write(hs.hello.marshal())
- c.writeRecord(recordTypeHandshake, hs.hello.marshal())
-
- certMsg := new(certificateMsg)
- certMsg.certificates = hs.cert.Certificate
- hs.finishedHash.Write(certMsg.marshal())
- c.writeRecord(recordTypeHandshake, certMsg.marshal())
-
- if hs.hello.ocspStapling {
- certStatus := new(certificateStatusMsg)
- certStatus.statusType = statusTypeOCSP
- certStatus.response = hs.cert.OCSPStaple
- hs.finishedHash.Write(certStatus.marshal())
- c.writeRecord(recordTypeHandshake, certStatus.marshal())
- }
-
- keyAgreement := hs.suite.ka(c.vers)
- skx, err := keyAgreement.generateServerKeyExchange(config, hs.cert, hs.clientHello, hs.hello)
- if err != nil {
- c.sendAlert(alertHandshakeFailure)
- return err
- }
- if skx != nil {
- hs.finishedHash.Write(skx.marshal())
- c.writeRecord(recordTypeHandshake, skx.marshal())
- }
-
- if config.ClientAuth >= RequestClientCert {
- // Request a client certificate
- certReq := new(certificateRequestMsg)
- certReq.certificateTypes = []byte{
- byte(certTypeRSASign),
- byte(certTypeECDSASign),
- }
- if c.vers >= VersionTLS12 {
- certReq.hasSignatureAndHash = true
- certReq.signatureAndHashes = supportedClientCertSignatureAlgorithms
- }
-
- // An empty list of certificateAuthorities signals to
- // the client that it may send any certificate in response
- // to our request. When we know the CAs we trust, then
- // we can send them down, so that the client can choose
- // an appropriate certificate to give to us.
- if config.ClientCAs != nil {
- certReq.certificateAuthorities = config.ClientCAs.Subjects()
- }
- hs.finishedHash.Write(certReq.marshal())
- c.writeRecord(recordTypeHandshake, certReq.marshal())
- }
-
- helloDone := new(serverHelloDoneMsg)
- hs.finishedHash.Write(helloDone.marshal())
- c.writeRecord(recordTypeHandshake, helloDone.marshal())
-
- var pub crypto.PublicKey // public key for client auth, if any
-
- msg, err := c.readHandshake()
- if err != nil {
- return err
- }
-
- var ok bool
- // If we requested a client certificate, then the client must send a
- // certificate message, even if it's empty.
- if config.ClientAuth >= RequestClientCert {
- if certMsg, ok = msg.(*certificateMsg); !ok {
- c.sendAlert(alertUnexpectedMessage)
- return unexpectedMessageError(certMsg, msg)
- }
- hs.finishedHash.Write(certMsg.marshal())
-
- if len(certMsg.certificates) == 0 {
- // The client didn't actually send a certificate
- switch config.ClientAuth {
- case RequireAnyClientCert, RequireAndVerifyClientCert:
- c.sendAlert(alertBadCertificate)
- return errors.New("tls: client didn't provide a certificate")
- }
- }
-
- pub, err = hs.processCertsFromClient(certMsg.certificates)
- if err != nil {
- return err
- }
-
- msg, err = c.readHandshake()
- if err != nil {
- return err
- }
- }
-
- // Get client key exchange
- ckx, ok := msg.(*clientKeyExchangeMsg)
- if !ok {
- c.sendAlert(alertUnexpectedMessage)
- return unexpectedMessageError(ckx, msg)
- }
- hs.finishedHash.Write(ckx.marshal())
-
- // If we received a client cert in response to our certificate request message,
- // the client will send us a certificateVerifyMsg immediately after the
- // clientKeyExchangeMsg. This message is a digest of all preceding
- // handshake-layer messages that is signed using the private key corresponding
- // to the client's certificate. This allows us to verify that the client is in
- // possession of the private key of the certificate.
- if len(c.peerCertificates) > 0 {
- msg, err = c.readHandshake()
- if err != nil {
- return err
- }
- certVerify, ok := msg.(*certificateVerifyMsg)
- if !ok {
- c.sendAlert(alertUnexpectedMessage)
- return unexpectedMessageError(certVerify, msg)
- }
-
- switch key := pub.(type) {
- case *ecdsa.PublicKey:
- ecdsaSig := new(ecdsaSignature)
- if _, err = asn1.Unmarshal(certVerify.signature, ecdsaSig); err != nil {
- break
- }
- if ecdsaSig.R.Sign() <= 0 || ecdsaSig.S.Sign() <= 0 {
- err = errors.New("ECDSA signature contained zero or negative values")
- break
- }
- digest, _, _ := hs.finishedHash.hashForClientCertificate(signatureECDSA)
- if !ecdsa.Verify(key, digest, ecdsaSig.R, ecdsaSig.S) {
- err = errors.New("ECDSA verification failure")
- break
- }
- case *rsa.PublicKey:
- digest, hashFunc, _ := hs.finishedHash.hashForClientCertificate(signatureRSA)
- err = rsa.VerifyPKCS1v15(key, hashFunc, digest, certVerify.signature)
- }
- if err != nil {
- c.sendAlert(alertBadCertificate)
- return errors.New("could not validate signature of connection nonces: " + err.Error())
- }
-
- hs.finishedHash.Write(certVerify.marshal())
- }
-
- preMasterSecret, err := keyAgreement.processClientKeyExchange(config, hs.cert, ckx, c.vers)
- if err != nil {
- c.sendAlert(alertHandshakeFailure)
- return err
- }
- hs.masterSecret = masterFromPreMasterSecret(c.vers, preMasterSecret, hs.clientHello.random, hs.hello.random)
-
- return nil
-}
-
-func (hs *serverHandshakeState) establishKeys() error {
- c := hs.c
-
- clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
- keysFromMasterSecret(c.vers, hs.masterSecret, hs.clientHello.random, hs.hello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
-
- var clientCipher, serverCipher interface{}
- var clientHash, serverHash macFunction
-
- if hs.suite.aead == nil {
- clientCipher = hs.suite.cipher(clientKey, clientIV, true /* for reading */)
- clientHash = hs.suite.mac(c.vers, clientMAC)
- serverCipher = hs.suite.cipher(serverKey, serverIV, false /* not for reading */)
- serverHash = hs.suite.mac(c.vers, serverMAC)
- } else {
- clientCipher = hs.suite.aead(clientKey, clientIV)
- serverCipher = hs.suite.aead(serverKey, serverIV)
- }
-
- c.in.prepareCipherSpec(c.vers, clientCipher, clientHash)
- c.out.prepareCipherSpec(c.vers, serverCipher, serverHash)
-
- return nil
-}
-
-func (hs *serverHandshakeState) readFinished() error {
- c := hs.c
-
- c.readRecord(recordTypeChangeCipherSpec)
- if err := c.in.error(); err != nil {
- return err
- }
-
- if hs.hello.nextProtoNeg {
- msg, err := c.readHandshake()
- if err != nil {
- return err
- }
- nextProto, ok := msg.(*nextProtoMsg)
- if !ok {
- c.sendAlert(alertUnexpectedMessage)
- return unexpectedMessageError(nextProto, msg)
- }
- hs.finishedHash.Write(nextProto.marshal())
- c.clientProtocol = nextProto.proto
- }
-
- msg, err := c.readHandshake()
- if err != nil {
- return err
- }
- clientFinished, ok := msg.(*finishedMsg)
- if !ok {
- c.sendAlert(alertUnexpectedMessage)
- return unexpectedMessageError(clientFinished, msg)
- }
-
- verify := hs.finishedHash.clientSum(hs.masterSecret)
- if len(verify) != len(clientFinished.verifyData) ||
- subtle.ConstantTimeCompare(verify, clientFinished.verifyData) != 1 {
- c.sendAlert(alertHandshakeFailure)
- return errors.New("tls: client's Finished message is incorrect")
- }
-
- hs.finishedHash.Write(clientFinished.marshal())
- return nil
-}
-
-func (hs *serverHandshakeState) sendSessionTicket() error {
- if !hs.hello.ticketSupported {
- return nil
- }
-
- c := hs.c
- m := new(newSessionTicketMsg)
-
- var err error
- state := sessionState{
- vers: c.vers,
- cipherSuite: hs.suite.id,
- masterSecret: hs.masterSecret,
- certificates: hs.certsFromClient,
- }
- m.ticket, err = c.encryptTicket(&state)
- if err != nil {
- return err
- }
-
- hs.finishedHash.Write(m.marshal())
- c.writeRecord(recordTypeHandshake, m.marshal())
-
- return nil
-}
-
-func (hs *serverHandshakeState) sendFinished() error {
- c := hs.c
-
- c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
-
- finished := new(finishedMsg)
- finished.verifyData = hs.finishedHash.serverSum(hs.masterSecret)
- hs.finishedHash.Write(finished.marshal())
- c.writeRecord(recordTypeHandshake, finished.marshal())
-
- c.cipherSuite = hs.suite.id
-
- return nil
-}
-
-// processCertsFromClient takes a chain of client certificates either from a
-// Certificates message or from a sessionState and verifies them. It returns
-// the public key of the leaf certificate.
-func (hs *serverHandshakeState) processCertsFromClient(certificates [][]byte) (crypto.PublicKey, error) {
- c := hs.c
-
- hs.certsFromClient = certificates
- certs := make([]*x509.Certificate, len(certificates))
- var err error
- for i, asn1Data := range certificates {
- if certs[i], err = x509.ParseCertificate(asn1Data); err != nil {
- c.sendAlert(alertBadCertificate)
- return nil, errors.New("tls: failed to parse client certificate: " + err.Error())
- }
- }
-
- if c.config.ClientAuth >= VerifyClientCertIfGiven && len(certs) > 0 {
- opts := x509.VerifyOptions{
- Roots: c.config.ClientCAs,
- CurrentTime: c.config.time(),
- Intermediates: x509.NewCertPool(),
- KeyUsages: []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
- }
-
- for _, cert := range certs[1:] {
- opts.Intermediates.AddCert(cert)
- }
-
- chains, err := certs[0].Verify(opts)
- if err != nil {
- c.sendAlert(alertBadCertificate)
- return nil, errors.New("tls: failed to verify client's certificate: " + err.Error())
- }
-
- ok := false
- for _, ku := range certs[0].ExtKeyUsage {
- if ku == x509.ExtKeyUsageClientAuth {
- ok = true
- break
- }
- }
- if !ok {
- c.sendAlert(alertHandshakeFailure)
- return nil, errors.New("tls: client's certificate's extended key usage doesn't permit it to be used for client authentication")
- }
-
- c.verifiedChains = chains
- }
-
- if len(certs) > 0 {
- var pub crypto.PublicKey
- switch key := certs[0].PublicKey.(type) {
- case *ecdsa.PublicKey, *rsa.PublicKey:
- pub = key
- default:
- c.sendAlert(alertUnsupportedCertificate)
- return nil, fmt.Errorf("tls: client's certificate contains an unsupported public key of type %T", certs[0].PublicKey)
- }
- c.peerCertificates = certs
- return pub, nil
- }
-
- return nil, nil
-}
-
-// tryCipherSuite returns a cipherSuite with the given id if that cipher suite
-// is acceptable to use.
-func (c *Conn) tryCipherSuite(id uint16, supportedCipherSuites []uint16, version uint16, ellipticOk, ecdsaOk bool) *cipherSuite {
- for _, supported := range supportedCipherSuites {
- if id == supported {
- var candidate *cipherSuite
-
- for _, s := range cipherSuites {
- if s.id == id {
- candidate = s
- break
- }
- }
- if candidate == nil {
- continue
- }
- // Don't select a ciphersuite which we can't
- // support for this client.
- if (candidate.flags&suiteECDHE != 0) && !ellipticOk {
- continue
- }
- if (candidate.flags&suiteECDSA != 0) != ecdsaOk {
- continue
- }
- if version < VersionTLS12 && candidate.flags&suiteTLS12 != 0 {
- continue
- }
- return candidate
- }
- }
-
- return nil
-}
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-29 07:17:57 +0000