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-rw-r--r--src/crypto/tls/handshake_client.go1011
1 files changed, 1011 insertions, 0 deletions
diff --git a/src/crypto/tls/handshake_client.go b/src/crypto/tls/handshake_client.go
new file mode 100644
index 0000000..a3e0077
--- /dev/null
+++ b/src/crypto/tls/handshake_client.go
@@ -0,0 +1,1011 @@
+// 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 (
+ "bytes"
+ "context"
+ "crypto"
+ "crypto/ecdsa"
+ "crypto/ed25519"
+ "crypto/rsa"
+ "crypto/subtle"
+ "crypto/x509"
+ "errors"
+ "fmt"
+ "hash"
+ "io"
+ "net"
+ "strings"
+ "sync/atomic"
+ "time"
+)
+
+type clientHandshakeState struct {
+ c *Conn
+ ctx context.Context
+ serverHello *serverHelloMsg
+ hello *clientHelloMsg
+ suite *cipherSuite
+ finishedHash finishedHash
+ masterSecret []byte
+ session *ClientSessionState
+}
+
+func (c *Conn) makeClientHello() (*clientHelloMsg, ecdheParameters, error) {
+ config := c.config
+ if len(config.ServerName) == 0 && !config.InsecureSkipVerify {
+ return nil, nil, errors.New("tls: either ServerName or InsecureSkipVerify must be specified in the tls.Config")
+ }
+
+ nextProtosLength := 0
+ for _, proto := range config.NextProtos {
+ if l := len(proto); l == 0 || l > 255 {
+ return nil, nil, errors.New("tls: invalid NextProtos value")
+ } else {
+ nextProtosLength += 1 + l
+ }
+ }
+ if nextProtosLength > 0xffff {
+ return nil, nil, errors.New("tls: NextProtos values too large")
+ }
+
+ supportedVersions := config.supportedVersions(roleClient)
+ if len(supportedVersions) == 0 {
+ return nil, nil, errors.New("tls: no supported versions satisfy MinVersion and MaxVersion")
+ }
+
+ clientHelloVersion := config.maxSupportedVersion(roleClient)
+ // The version at the beginning of the ClientHello was capped at TLS 1.2
+ // for compatibility reasons. The supported_versions extension is used
+ // to negotiate versions now. See RFC 8446, Section 4.2.1.
+ if clientHelloVersion > VersionTLS12 {
+ clientHelloVersion = VersionTLS12
+ }
+
+ hello := &clientHelloMsg{
+ vers: clientHelloVersion,
+ compressionMethods: []uint8{compressionNone},
+ random: make([]byte, 32),
+ sessionId: make([]byte, 32),
+ ocspStapling: true,
+ scts: true,
+ serverName: hostnameInSNI(config.ServerName),
+ supportedCurves: config.curvePreferences(),
+ supportedPoints: []uint8{pointFormatUncompressed},
+ secureRenegotiationSupported: true,
+ alpnProtocols: config.NextProtos,
+ supportedVersions: supportedVersions,
+ }
+
+ if c.handshakes > 0 {
+ hello.secureRenegotiation = c.clientFinished[:]
+ }
+
+ preferenceOrder := cipherSuitesPreferenceOrder
+ if !hasAESGCMHardwareSupport {
+ preferenceOrder = cipherSuitesPreferenceOrderNoAES
+ }
+ configCipherSuites := config.cipherSuites()
+ hello.cipherSuites = make([]uint16, 0, len(configCipherSuites))
+
+ for _, suiteId := range preferenceOrder {
+ suite := mutualCipherSuite(configCipherSuites, suiteId)
+ if suite == nil {
+ continue
+ }
+ // Don't advertise TLS 1.2-only cipher suites unless
+ // we're attempting TLS 1.2.
+ if hello.vers < VersionTLS12 && suite.flags&suiteTLS12 != 0 {
+ continue
+ }
+ hello.cipherSuites = append(hello.cipherSuites, suiteId)
+ }
+
+ _, err := io.ReadFull(config.rand(), hello.random)
+ if err != nil {
+ return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
+ }
+
+ // A random session ID is used to detect when the server accepted a ticket
+ // and is resuming a session (see RFC 5077). In TLS 1.3, it's always set as
+ // a compatibility measure (see RFC 8446, Section 4.1.2).
+ if _, err := io.ReadFull(config.rand(), hello.sessionId); err != nil {
+ return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
+ }
+
+ if hello.vers >= VersionTLS12 {
+ hello.supportedSignatureAlgorithms = supportedSignatureAlgorithms
+ }
+
+ var params ecdheParameters
+ if hello.supportedVersions[0] == VersionTLS13 {
+ if hasAESGCMHardwareSupport {
+ hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13...)
+ } else {
+ hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13NoAES...)
+ }
+
+ curveID := config.curvePreferences()[0]
+ if _, ok := curveForCurveID(curveID); curveID != X25519 && !ok {
+ return nil, nil, errors.New("tls: CurvePreferences includes unsupported curve")
+ }
+ params, err = generateECDHEParameters(config.rand(), curveID)
+ if err != nil {
+ return nil, nil, err
+ }
+ hello.keyShares = []keyShare{{group: curveID, data: params.PublicKey()}}
+ }
+
+ return hello, params, nil
+}
+
+func (c *Conn) clientHandshake(ctx context.Context) (err error) {
+ if c.config == nil {
+ c.config = defaultConfig()
+ }
+
+ // This may be a renegotiation handshake, in which case some fields
+ // need to be reset.
+ c.didResume = false
+
+ hello, ecdheParams, err := c.makeClientHello()
+ if err != nil {
+ return err
+ }
+ c.serverName = hello.serverName
+
+ cacheKey, session, earlySecret, binderKey := c.loadSession(hello)
+ if cacheKey != "" && session != nil {
+ defer func() {
+ // If we got a handshake failure when resuming a session, throw away
+ // the session ticket. See RFC 5077, Section 3.2.
+ //
+ // RFC 8446 makes no mention of dropping tickets on failure, but it
+ // does require servers to abort on invalid binders, so we need to
+ // delete tickets to recover from a corrupted PSK.
+ if err != nil {
+ c.config.ClientSessionCache.Put(cacheKey, nil)
+ }
+ }()
+ }
+
+ if _, err := c.writeRecord(recordTypeHandshake, hello.marshal()); err != nil {
+ return err
+ }
+
+ msg, err := c.readHandshake()
+ if err != nil {
+ return err
+ }
+
+ serverHello, ok := msg.(*serverHelloMsg)
+ if !ok {
+ c.sendAlert(alertUnexpectedMessage)
+ return unexpectedMessageError(serverHello, msg)
+ }
+
+ if err := c.pickTLSVersion(serverHello); err != nil {
+ return err
+ }
+
+ // If we are negotiating a protocol version that's lower than what we
+ // support, check for the server downgrade canaries.
+ // See RFC 8446, Section 4.1.3.
+ maxVers := c.config.maxSupportedVersion(roleClient)
+ tls12Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS12
+ tls11Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS11
+ if maxVers == VersionTLS13 && c.vers <= VersionTLS12 && (tls12Downgrade || tls11Downgrade) ||
+ maxVers == VersionTLS12 && c.vers <= VersionTLS11 && tls11Downgrade {
+ c.sendAlert(alertIllegalParameter)
+ return errors.New("tls: downgrade attempt detected, possibly due to a MitM attack or a broken middlebox")
+ }
+
+ if c.vers == VersionTLS13 {
+ hs := &clientHandshakeStateTLS13{
+ c: c,
+ ctx: ctx,
+ serverHello: serverHello,
+ hello: hello,
+ ecdheParams: ecdheParams,
+ session: session,
+ earlySecret: earlySecret,
+ binderKey: binderKey,
+ }
+
+ // In TLS 1.3, session tickets are delivered after the handshake.
+ return hs.handshake()
+ }
+
+ hs := &clientHandshakeState{
+ c: c,
+ ctx: ctx,
+ serverHello: serverHello,
+ hello: hello,
+ session: session,
+ }
+
+ if err := hs.handshake(); err != nil {
+ return err
+ }
+
+ // If we had a successful handshake and hs.session is different from
+ // the one already cached - cache a new one.
+ if cacheKey != "" && hs.session != nil && session != hs.session {
+ c.config.ClientSessionCache.Put(cacheKey, hs.session)
+ }
+
+ return nil
+}
+
+func (c *Conn) loadSession(hello *clientHelloMsg) (cacheKey string,
+ session *ClientSessionState, earlySecret, binderKey []byte) {
+ if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
+ return "", nil, nil, nil
+ }
+
+ hello.ticketSupported = true
+
+ if hello.supportedVersions[0] == VersionTLS13 {
+ // Require DHE on resumption as it guarantees forward secrecy against
+ // compromise of the session ticket key. See RFC 8446, Section 4.2.9.
+ hello.pskModes = []uint8{pskModeDHE}
+ }
+
+ // Session resumption is not allowed if renegotiating because
+ // renegotiation is primarily used to allow a client to send a client
+ // certificate, which would be skipped if session resumption occurred.
+ if c.handshakes != 0 {
+ return "", nil, nil, nil
+ }
+
+ // Try to resume a previously negotiated TLS session, if available.
+ cacheKey = clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
+ session, ok := c.config.ClientSessionCache.Get(cacheKey)
+ if !ok || session == nil {
+ return cacheKey, nil, nil, nil
+ }
+
+ // Check that version used for the previous session is still valid.
+ versOk := false
+ for _, v := range hello.supportedVersions {
+ if v == session.vers {
+ versOk = true
+ break
+ }
+ }
+ if !versOk {
+ return cacheKey, nil, nil, nil
+ }
+
+ // Check that the cached server certificate is not expired, and that it's
+ // valid for the ServerName. This should be ensured by the cache key, but
+ // protect the application from a faulty ClientSessionCache implementation.
+ if !c.config.InsecureSkipVerify {
+ if len(session.verifiedChains) == 0 {
+ // The original connection had InsecureSkipVerify, while this doesn't.
+ return cacheKey, nil, nil, nil
+ }
+ serverCert := session.serverCertificates[0]
+ if c.config.time().After(serverCert.NotAfter) {
+ // Expired certificate, delete the entry.
+ c.config.ClientSessionCache.Put(cacheKey, nil)
+ return cacheKey, nil, nil, nil
+ }
+ if err := serverCert.VerifyHostname(c.config.ServerName); err != nil {
+ return cacheKey, nil, nil, nil
+ }
+ }
+
+ if session.vers != VersionTLS13 {
+ // In TLS 1.2 the cipher suite must match the resumed session. Ensure we
+ // are still offering it.
+ if mutualCipherSuite(hello.cipherSuites, session.cipherSuite) == nil {
+ return cacheKey, nil, nil, nil
+ }
+
+ hello.sessionTicket = session.sessionTicket
+ return
+ }
+
+ // Check that the session ticket is not expired.
+ if c.config.time().After(session.useBy) {
+ c.config.ClientSessionCache.Put(cacheKey, nil)
+ return cacheKey, nil, nil, nil
+ }
+
+ // In TLS 1.3 the KDF hash must match the resumed session. Ensure we
+ // offer at least one cipher suite with that hash.
+ cipherSuite := cipherSuiteTLS13ByID(session.cipherSuite)
+ if cipherSuite == nil {
+ return cacheKey, nil, nil, nil
+ }
+ cipherSuiteOk := false
+ for _, offeredID := range hello.cipherSuites {
+ offeredSuite := cipherSuiteTLS13ByID(offeredID)
+ if offeredSuite != nil && offeredSuite.hash == cipherSuite.hash {
+ cipherSuiteOk = true
+ break
+ }
+ }
+ if !cipherSuiteOk {
+ return cacheKey, nil, nil, nil
+ }
+
+ // Set the pre_shared_key extension. See RFC 8446, Section 4.2.11.1.
+ ticketAge := uint32(c.config.time().Sub(session.receivedAt) / time.Millisecond)
+ identity := pskIdentity{
+ label: session.sessionTicket,
+ obfuscatedTicketAge: ticketAge + session.ageAdd,
+ }
+ hello.pskIdentities = []pskIdentity{identity}
+ hello.pskBinders = [][]byte{make([]byte, cipherSuite.hash.Size())}
+
+ // Compute the PSK binders. See RFC 8446, Section 4.2.11.2.
+ psk := cipherSuite.expandLabel(session.masterSecret, "resumption",
+ session.nonce, cipherSuite.hash.Size())
+ earlySecret = cipherSuite.extract(psk, nil)
+ binderKey = cipherSuite.deriveSecret(earlySecret, resumptionBinderLabel, nil)
+ transcript := cipherSuite.hash.New()
+ transcript.Write(hello.marshalWithoutBinders())
+ pskBinders := [][]byte{cipherSuite.finishedHash(binderKey, transcript)}
+ hello.updateBinders(pskBinders)
+
+ return
+}
+
+func (c *Conn) pickTLSVersion(serverHello *serverHelloMsg) error {
+ peerVersion := serverHello.vers
+ if serverHello.supportedVersion != 0 {
+ peerVersion = serverHello.supportedVersion
+ }
+
+ vers, ok := c.config.mutualVersion(roleClient, []uint16{peerVersion})
+ if !ok {
+ c.sendAlert(alertProtocolVersion)
+ return fmt.Errorf("tls: server selected unsupported protocol version %x", peerVersion)
+ }
+
+ c.vers = vers
+ c.haveVers = true
+ c.in.version = vers
+ c.out.version = vers
+
+ return nil
+}
+
+// Does the handshake, either a full one or resumes old session. Requires hs.c,
+// hs.hello, hs.serverHello, and, optionally, hs.session to be set.
+func (hs *clientHandshakeState) handshake() error {
+ c := hs.c
+
+ isResume, err := hs.processServerHello()
+ if err != nil {
+ return err
+ }
+
+ hs.finishedHash = newFinishedHash(c.vers, hs.suite)
+
+ // No signatures of the handshake are needed in a resumption.
+ // Otherwise, in a full handshake, if we don't have any certificates
+ // configured then we will never send a CertificateVerify message and
+ // thus no signatures are needed in that case either.
+ if isResume || (len(c.config.Certificates) == 0 && c.config.GetClientCertificate == nil) {
+ hs.finishedHash.discardHandshakeBuffer()
+ }
+
+ hs.finishedHash.Write(hs.hello.marshal())
+ hs.finishedHash.Write(hs.serverHello.marshal())
+
+ c.buffering = true
+ c.didResume = isResume
+ if isResume {
+ if err := hs.establishKeys(); err != nil {
+ return err
+ }
+ if err := hs.readSessionTicket(); err != nil {
+ return err
+ }
+ if err := hs.readFinished(c.serverFinished[:]); err != nil {
+ return err
+ }
+ c.clientFinishedIsFirst = false
+ // Make sure the connection is still being verified whether or not this
+ // is a resumption. Resumptions currently don't reverify certificates so
+ // they don't call verifyServerCertificate. See Issue 31641.
+ if c.config.VerifyConnection != nil {
+ if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+ c.sendAlert(alertBadCertificate)
+ return err
+ }
+ }
+ if err := hs.sendFinished(c.clientFinished[:]); err != nil {
+ return err
+ }
+ if _, err := c.flush(); err != nil {
+ return err
+ }
+ } else {
+ if err := hs.doFullHandshake(); err != nil {
+ return err
+ }
+ if err := hs.establishKeys(); err != nil {
+ return err
+ }
+ if err := hs.sendFinished(c.clientFinished[:]); err != nil {
+ return err
+ }
+ if _, err := c.flush(); err != nil {
+ return err
+ }
+ c.clientFinishedIsFirst = true
+ if err := hs.readSessionTicket(); err != nil {
+ return err
+ }
+ if err := hs.readFinished(c.serverFinished[:]); err != nil {
+ return err
+ }
+ }
+
+ c.ekm = ekmFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random)
+ atomic.StoreUint32(&c.handshakeStatus, 1)
+
+ return nil
+}
+
+func (hs *clientHandshakeState) pickCipherSuite() error {
+ if hs.suite = mutualCipherSuite(hs.hello.cipherSuites, hs.serverHello.cipherSuite); hs.suite == nil {
+ hs.c.sendAlert(alertHandshakeFailure)
+ return errors.New("tls: server chose an unconfigured cipher suite")
+ }
+
+ hs.c.cipherSuite = hs.suite.id
+ return nil
+}
+
+func (hs *clientHandshakeState) doFullHandshake() error {
+ c := hs.c
+
+ msg, err := c.readHandshake()
+ if err != nil {
+ return err
+ }
+ certMsg, ok := msg.(*certificateMsg)
+ if !ok || len(certMsg.certificates) == 0 {
+ c.sendAlert(alertUnexpectedMessage)
+ return unexpectedMessageError(certMsg, msg)
+ }
+ hs.finishedHash.Write(certMsg.marshal())
+
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+
+ cs, ok := msg.(*certificateStatusMsg)
+ if ok {
+ // RFC4366 on Certificate Status Request:
+ // The server MAY return a "certificate_status" message.
+
+ if !hs.serverHello.ocspStapling {
+ // If a server returns a "CertificateStatus" message, then the
+ // server MUST have included an extension of type "status_request"
+ // with empty "extension_data" in the extended server hello.
+
+ c.sendAlert(alertUnexpectedMessage)
+ return errors.New("tls: received unexpected CertificateStatus message")
+ }
+ hs.finishedHash.Write(cs.marshal())
+
+ c.ocspResponse = cs.response
+
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ }
+
+ if c.handshakes == 0 {
+ // If this is the first handshake on a connection, process and
+ // (optionally) verify the server's certificates.
+ if err := c.verifyServerCertificate(certMsg.certificates); err != nil {
+ return err
+ }
+ } else {
+ // This is a renegotiation handshake. We require that the
+ // server's identity (i.e. leaf certificate) is unchanged and
+ // thus any previous trust decision is still valid.
+ //
+ // See https://mitls.org/pages/attacks/3SHAKE for the
+ // motivation behind this requirement.
+ if !bytes.Equal(c.peerCertificates[0].Raw, certMsg.certificates[0]) {
+ c.sendAlert(alertBadCertificate)
+ return errors.New("tls: server's identity changed during renegotiation")
+ }
+ }
+
+ keyAgreement := hs.suite.ka(c.vers)
+
+ skx, ok := msg.(*serverKeyExchangeMsg)
+ if ok {
+ hs.finishedHash.Write(skx.marshal())
+ err = keyAgreement.processServerKeyExchange(c.config, hs.hello, hs.serverHello, c.peerCertificates[0], skx)
+ if err != nil {
+ c.sendAlert(alertUnexpectedMessage)
+ return err
+ }
+
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ }
+
+ var chainToSend *Certificate
+ var certRequested bool
+ certReq, ok := msg.(*certificateRequestMsg)
+ if ok {
+ certRequested = true
+ hs.finishedHash.Write(certReq.marshal())
+
+ cri := certificateRequestInfoFromMsg(hs.ctx, c.vers, certReq)
+ if chainToSend, err = c.getClientCertificate(cri); err != nil {
+ c.sendAlert(alertInternalError)
+ return err
+ }
+
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ }
+
+ shd, ok := msg.(*serverHelloDoneMsg)
+ if !ok {
+ c.sendAlert(alertUnexpectedMessage)
+ return unexpectedMessageError(shd, msg)
+ }
+ hs.finishedHash.Write(shd.marshal())
+
+ // If the server requested a certificate then we have to send a
+ // Certificate message, even if it's empty because we don't have a
+ // certificate to send.
+ if certRequested {
+ certMsg = new(certificateMsg)
+ certMsg.certificates = chainToSend.Certificate
+ hs.finishedHash.Write(certMsg.marshal())
+ if _, err := c.writeRecord(recordTypeHandshake, certMsg.marshal()); err != nil {
+ return err
+ }
+ }
+
+ preMasterSecret, ckx, err := keyAgreement.generateClientKeyExchange(c.config, hs.hello, c.peerCertificates[0])
+ if err != nil {
+ c.sendAlert(alertInternalError)
+ return err
+ }
+ if ckx != nil {
+ hs.finishedHash.Write(ckx.marshal())
+ if _, err := c.writeRecord(recordTypeHandshake, ckx.marshal()); err != nil {
+ return err
+ }
+ }
+
+ if chainToSend != nil && len(chainToSend.Certificate) > 0 {
+ certVerify := &certificateVerifyMsg{}
+
+ key, ok := chainToSend.PrivateKey.(crypto.Signer)
+ if !ok {
+ c.sendAlert(alertInternalError)
+ return fmt.Errorf("tls: client certificate private key of type %T does not implement crypto.Signer", chainToSend.PrivateKey)
+ }
+
+ var sigType uint8
+ var sigHash crypto.Hash
+ if c.vers >= VersionTLS12 {
+ signatureAlgorithm, err := selectSignatureScheme(c.vers, chainToSend, certReq.supportedSignatureAlgorithms)
+ if err != nil {
+ c.sendAlert(alertIllegalParameter)
+ return err
+ }
+ sigType, sigHash, err = typeAndHashFromSignatureScheme(signatureAlgorithm)
+ if err != nil {
+ return c.sendAlert(alertInternalError)
+ }
+ certVerify.hasSignatureAlgorithm = true
+ certVerify.signatureAlgorithm = signatureAlgorithm
+ } else {
+ sigType, sigHash, err = legacyTypeAndHashFromPublicKey(key.Public())
+ if err != nil {
+ c.sendAlert(alertIllegalParameter)
+ return err
+ }
+ }
+
+ signed := hs.finishedHash.hashForClientCertificate(sigType, sigHash, hs.masterSecret)
+ signOpts := crypto.SignerOpts(sigHash)
+ if sigType == signatureRSAPSS {
+ signOpts = &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash, Hash: sigHash}
+ }
+ certVerify.signature, err = key.Sign(c.config.rand(), signed, signOpts)
+ if err != nil {
+ c.sendAlert(alertInternalError)
+ return err
+ }
+
+ hs.finishedHash.Write(certVerify.marshal())
+ if _, err := c.writeRecord(recordTypeHandshake, certVerify.marshal()); err != nil {
+ return err
+ }
+ }
+
+ hs.masterSecret = masterFromPreMasterSecret(c.vers, hs.suite, preMasterSecret, hs.hello.random, hs.serverHello.random)
+ if err := c.config.writeKeyLog(keyLogLabelTLS12, hs.hello.random, hs.masterSecret); err != nil {
+ c.sendAlert(alertInternalError)
+ return errors.New("tls: failed to write to key log: " + err.Error())
+ }
+
+ hs.finishedHash.discardHandshakeBuffer()
+
+ return nil
+}
+
+func (hs *clientHandshakeState) establishKeys() error {
+ c := hs.c
+
+ clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
+ keysFromMasterSecret(c.vers, hs.suite, hs.masterSecret, hs.hello.random, hs.serverHello.random, hs.suite.macLen, hs.suite.keyLen, hs.suite.ivLen)
+ var clientCipher, serverCipher any
+ var clientHash, serverHash hash.Hash
+ if hs.suite.cipher != nil {
+ clientCipher = hs.suite.cipher(clientKey, clientIV, false /* not for reading */)
+ clientHash = hs.suite.mac(clientMAC)
+ serverCipher = hs.suite.cipher(serverKey, serverIV, true /* for reading */)
+ serverHash = hs.suite.mac(serverMAC)
+ } else {
+ clientCipher = hs.suite.aead(clientKey, clientIV)
+ serverCipher = hs.suite.aead(serverKey, serverIV)
+ }
+
+ c.in.prepareCipherSpec(c.vers, serverCipher, serverHash)
+ c.out.prepareCipherSpec(c.vers, clientCipher, clientHash)
+ return nil
+}
+
+func (hs *clientHandshakeState) serverResumedSession() bool {
+ // If the server responded with the same sessionId then it means the
+ // sessionTicket is being used to resume a TLS session.
+ return hs.session != nil && hs.hello.sessionId != nil &&
+ bytes.Equal(hs.serverHello.sessionId, hs.hello.sessionId)
+}
+
+func (hs *clientHandshakeState) processServerHello() (bool, error) {
+ c := hs.c
+
+ if err := hs.pickCipherSuite(); err != nil {
+ return false, err
+ }
+
+ if hs.serverHello.compressionMethod != compressionNone {
+ c.sendAlert(alertUnexpectedMessage)
+ return false, errors.New("tls: server selected unsupported compression format")
+ }
+
+ if c.handshakes == 0 && hs.serverHello.secureRenegotiationSupported {
+ c.secureRenegotiation = true
+ if len(hs.serverHello.secureRenegotiation) != 0 {
+ c.sendAlert(alertHandshakeFailure)
+ return false, errors.New("tls: initial handshake had non-empty renegotiation extension")
+ }
+ }
+
+ if c.handshakes > 0 && c.secureRenegotiation {
+ var expectedSecureRenegotiation [24]byte
+ copy(expectedSecureRenegotiation[:], c.clientFinished[:])
+ copy(expectedSecureRenegotiation[12:], c.serverFinished[:])
+ if !bytes.Equal(hs.serverHello.secureRenegotiation, expectedSecureRenegotiation[:]) {
+ c.sendAlert(alertHandshakeFailure)
+ return false, errors.New("tls: incorrect renegotiation extension contents")
+ }
+ }
+
+ if err := checkALPN(hs.hello.alpnProtocols, hs.serverHello.alpnProtocol); err != nil {
+ c.sendAlert(alertUnsupportedExtension)
+ return false, err
+ }
+ c.clientProtocol = hs.serverHello.alpnProtocol
+
+ c.scts = hs.serverHello.scts
+
+ if !hs.serverResumedSession() {
+ return false, nil
+ }
+
+ if hs.session.vers != c.vers {
+ c.sendAlert(alertHandshakeFailure)
+ return false, errors.New("tls: server resumed a session with a different version")
+ }
+
+ if hs.session.cipherSuite != hs.suite.id {
+ c.sendAlert(alertHandshakeFailure)
+ return false, errors.New("tls: server resumed a session with a different cipher suite")
+ }
+
+ // Restore masterSecret, peerCerts, and ocspResponse from previous state
+ hs.masterSecret = hs.session.masterSecret
+ c.peerCertificates = hs.session.serverCertificates
+ c.verifiedChains = hs.session.verifiedChains
+ c.ocspResponse = hs.session.ocspResponse
+ // Let the ServerHello SCTs override the session SCTs from the original
+ // connection, if any are provided
+ if len(c.scts) == 0 && len(hs.session.scts) != 0 {
+ c.scts = hs.session.scts
+ }
+
+ return true, nil
+}
+
+// checkALPN ensure that the server's choice of ALPN protocol is compatible with
+// the protocols that we advertised in the Client Hello.
+func checkALPN(clientProtos []string, serverProto string) error {
+ if serverProto == "" {
+ return nil
+ }
+ if len(clientProtos) == 0 {
+ return errors.New("tls: server advertised unrequested ALPN extension")
+ }
+ for _, proto := range clientProtos {
+ if proto == serverProto {
+ return nil
+ }
+ }
+ return errors.New("tls: server selected unadvertised ALPN protocol")
+}
+
+func (hs *clientHandshakeState) readFinished(out []byte) error {
+ c := hs.c
+
+ if err := c.readChangeCipherSpec(); err != nil {
+ return err
+ }
+
+ msg, err := c.readHandshake()
+ if err != nil {
+ return err
+ }
+ serverFinished, ok := msg.(*finishedMsg)
+ if !ok {
+ c.sendAlert(alertUnexpectedMessage)
+ return unexpectedMessageError(serverFinished, msg)
+ }
+
+ verify := hs.finishedHash.serverSum(hs.masterSecret)
+ if len(verify) != len(serverFinished.verifyData) ||
+ subtle.ConstantTimeCompare(verify, serverFinished.verifyData) != 1 {
+ c.sendAlert(alertHandshakeFailure)
+ return errors.New("tls: server's Finished message was incorrect")
+ }
+ hs.finishedHash.Write(serverFinished.marshal())
+ copy(out, verify)
+ return nil
+}
+
+func (hs *clientHandshakeState) readSessionTicket() error {
+ if !hs.serverHello.ticketSupported {
+ return nil
+ }
+
+ c := hs.c
+ msg, err := c.readHandshake()
+ if err != nil {
+ return err
+ }
+ sessionTicketMsg, ok := msg.(*newSessionTicketMsg)
+ if !ok {
+ c.sendAlert(alertUnexpectedMessage)
+ return unexpectedMessageError(sessionTicketMsg, msg)
+ }
+ hs.finishedHash.Write(sessionTicketMsg.marshal())
+
+ hs.session = &ClientSessionState{
+ sessionTicket: sessionTicketMsg.ticket,
+ vers: c.vers,
+ cipherSuite: hs.suite.id,
+ masterSecret: hs.masterSecret,
+ serverCertificates: c.peerCertificates,
+ verifiedChains: c.verifiedChains,
+ receivedAt: c.config.time(),
+ ocspResponse: c.ocspResponse,
+ scts: c.scts,
+ }
+
+ return nil
+}
+
+func (hs *clientHandshakeState) sendFinished(out []byte) error {
+ c := hs.c
+
+ if _, err := c.writeRecord(recordTypeChangeCipherSpec, []byte{1}); err != nil {
+ return err
+ }
+
+ finished := new(finishedMsg)
+ finished.verifyData = hs.finishedHash.clientSum(hs.masterSecret)
+ hs.finishedHash.Write(finished.marshal())
+ if _, err := c.writeRecord(recordTypeHandshake, finished.marshal()); err != nil {
+ return err
+ }
+ copy(out, finished.verifyData)
+ return nil
+}
+
+// verifyServerCertificate parses and verifies the provided chain, setting
+// c.verifiedChains and c.peerCertificates or sending the appropriate alert.
+func (c *Conn) verifyServerCertificate(certificates [][]byte) error {
+ certs := make([]*x509.Certificate, len(certificates))
+ for i, asn1Data := range certificates {
+ cert, err := x509.ParseCertificate(asn1Data)
+ if err != nil {
+ c.sendAlert(alertBadCertificate)
+ return errors.New("tls: failed to parse certificate from server: " + err.Error())
+ }
+ certs[i] = cert
+ }
+
+ if !c.config.InsecureSkipVerify {
+ opts := x509.VerifyOptions{
+ Roots: c.config.RootCAs,
+ CurrentTime: c.config.time(),
+ DNSName: c.config.ServerName,
+ Intermediates: x509.NewCertPool(),
+ }
+ for _, cert := range certs[1:] {
+ opts.Intermediates.AddCert(cert)
+ }
+ var err error
+ c.verifiedChains, err = certs[0].Verify(opts)
+ if err != nil {
+ c.sendAlert(alertBadCertificate)
+ return err
+ }
+ }
+
+ switch certs[0].PublicKey.(type) {
+ case *rsa.PublicKey, *ecdsa.PublicKey, ed25519.PublicKey:
+ break
+ default:
+ c.sendAlert(alertUnsupportedCertificate)
+ return fmt.Errorf("tls: server's certificate contains an unsupported type of public key: %T", certs[0].PublicKey)
+ }
+
+ c.peerCertificates = certs
+
+ if c.config.VerifyPeerCertificate != nil {
+ if err := c.config.VerifyPeerCertificate(certificates, c.verifiedChains); err != nil {
+ c.sendAlert(alertBadCertificate)
+ return err
+ }
+ }
+
+ if c.config.VerifyConnection != nil {
+ if err := c.config.VerifyConnection(c.connectionStateLocked()); err != nil {
+ c.sendAlert(alertBadCertificate)
+ return err
+ }
+ }
+
+ return nil
+}
+
+// certificateRequestInfoFromMsg generates a CertificateRequestInfo from a TLS
+// <= 1.2 CertificateRequest, making an effort to fill in missing information.
+func certificateRequestInfoFromMsg(ctx context.Context, vers uint16, certReq *certificateRequestMsg) *CertificateRequestInfo {
+ cri := &CertificateRequestInfo{
+ AcceptableCAs: certReq.certificateAuthorities,
+ Version: vers,
+ ctx: ctx,
+ }
+
+ var rsaAvail, ecAvail bool
+ for _, certType := range certReq.certificateTypes {
+ switch certType {
+ case certTypeRSASign:
+ rsaAvail = true
+ case certTypeECDSASign:
+ ecAvail = true
+ }
+ }
+
+ if !certReq.hasSignatureAlgorithm {
+ // Prior to TLS 1.2, signature schemes did not exist. In this case we
+ // make up a list based on the acceptable certificate types, to help
+ // GetClientCertificate and SupportsCertificate select the right certificate.
+ // The hash part of the SignatureScheme is a lie here, because
+ // TLS 1.0 and 1.1 always use MD5+SHA1 for RSA and SHA1 for ECDSA.
+ switch {
+ case rsaAvail && ecAvail:
+ cri.SignatureSchemes = []SignatureScheme{
+ ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
+ PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
+ }
+ case rsaAvail:
+ cri.SignatureSchemes = []SignatureScheme{
+ PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512, PKCS1WithSHA1,
+ }
+ case ecAvail:
+ cri.SignatureSchemes = []SignatureScheme{
+ ECDSAWithP256AndSHA256, ECDSAWithP384AndSHA384, ECDSAWithP521AndSHA512,
+ }
+ }
+ return cri
+ }
+
+ // Filter the signature schemes based on the certificate types.
+ // See RFC 5246, Section 7.4.4 (where it calls this "somewhat complicated").
+ cri.SignatureSchemes = make([]SignatureScheme, 0, len(certReq.supportedSignatureAlgorithms))
+ for _, sigScheme := range certReq.supportedSignatureAlgorithms {
+ sigType, _, err := typeAndHashFromSignatureScheme(sigScheme)
+ if err != nil {
+ continue
+ }
+ switch sigType {
+ case signatureECDSA, signatureEd25519:
+ if ecAvail {
+ cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
+ }
+ case signatureRSAPSS, signaturePKCS1v15:
+ if rsaAvail {
+ cri.SignatureSchemes = append(cri.SignatureSchemes, sigScheme)
+ }
+ }
+ }
+
+ return cri
+}
+
+func (c *Conn) getClientCertificate(cri *CertificateRequestInfo) (*Certificate, error) {
+ if c.config.GetClientCertificate != nil {
+ return c.config.GetClientCertificate(cri)
+ }
+
+ for _, chain := range c.config.Certificates {
+ if err := cri.SupportsCertificate(&chain); err != nil {
+ continue
+ }
+ return &chain, nil
+ }
+
+ // No acceptable certificate found. Don't send a certificate.
+ return new(Certificate), nil
+}
+
+// clientSessionCacheKey returns a key used to cache sessionTickets that could
+// be used to resume previously negotiated TLS sessions with a server.
+func clientSessionCacheKey(serverAddr net.Addr, config *Config) string {
+ if len(config.ServerName) > 0 {
+ return config.ServerName
+ }
+ return serverAddr.String()
+}
+
+// hostnameInSNI converts name into an appropriate hostname for SNI.
+// Literal IP addresses and absolute FQDNs are not permitted as SNI values.
+// See RFC 6066, Section 3.
+func hostnameInSNI(name string) string {
+ host := name
+ if len(host) > 0 && host[0] == '[' && host[len(host)-1] == ']' {
+ host = host[1 : len(host)-1]
+ }
+ if i := strings.LastIndex(host, "%"); i > 0 {
+ host = host[:i]
+ }
+ if net.ParseIP(host) != nil {
+ return ""
+ }
+ for len(name) > 0 && name[len(name)-1] == '.' {
+ name = name[:len(name)-1]
+ }
+ return name
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 01:21:00 +0000