1135 lines
34 KiB
Go
1135 lines
34 KiB
Go
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package qtls
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import (
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"bytes"
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"context"
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"crypto"
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"crypto/ecdh"
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"crypto/ecdsa"
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"crypto/ed25519"
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"crypto/rsa"
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"crypto/subtle"
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"crypto/x509"
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"errors"
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"fmt"
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"hash"
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"io"
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"net"
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"strings"
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"time"
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"golang.org/x/crypto/cryptobyte"
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)
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const clientSessionStateVersion = 1
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type clientHandshakeState struct {
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c *Conn
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ctx context.Context
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serverHello *serverHelloMsg
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hello *clientHelloMsg
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suite *cipherSuite
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finishedHash finishedHash
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masterSecret []byte
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session *clientSessionState
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}
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var testingOnlyForceClientHelloSignatureAlgorithms []SignatureScheme
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func (c *Conn) makeClientHello() (*clientHelloMsg, *ecdh.PrivateKey, error) {
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config := c.config
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if len(config.ServerName) == 0 && !config.InsecureSkipVerify {
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return nil, nil, errors.New("tls: either ServerName or InsecureSkipVerify must be specified in the tls.Config")
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}
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nextProtosLength := 0
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for _, proto := range config.NextProtos {
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if l := len(proto); l == 0 || l > 255 {
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return nil, nil, errors.New("tls: invalid NextProtos value")
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} else {
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nextProtosLength += 1 + l
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}
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}
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if nextProtosLength > 0xffff {
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return nil, nil, errors.New("tls: NextProtos values too large")
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}
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var supportedVersions []uint16
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var clientHelloVersion uint16
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if c.extraConfig.usesAlternativeRecordLayer() {
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if config.maxSupportedVersion(roleClient) < VersionTLS13 {
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return nil, nil, errors.New("tls: MaxVersion prevents QUIC from using TLS 1.3")
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}
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// Only offer TLS 1.3 when QUIC is used.
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supportedVersions = []uint16{VersionTLS13}
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clientHelloVersion = VersionTLS13
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} else {
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supportedVersions = config.supportedVersions(roleClient)
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if len(supportedVersions) == 0 {
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return nil, nil, errors.New("tls: no supported versions satisfy MinVersion and MaxVersion")
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}
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clientHelloVersion = config.maxSupportedVersion(roleClient)
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}
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// The version at the beginning of the ClientHello was capped at TLS 1.2
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// for compatibility reasons. The supported_versions extension is used
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// to negotiate versions now. See RFC 8446, Section 4.2.1.
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if clientHelloVersion > VersionTLS12 {
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clientHelloVersion = VersionTLS12
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}
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hello := &clientHelloMsg{
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vers: clientHelloVersion,
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compressionMethods: []uint8{compressionNone},
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random: make([]byte, 32),
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ocspStapling: true,
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scts: true,
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serverName: hostnameInSNI(config.ServerName),
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supportedCurves: config.curvePreferences(),
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supportedPoints: []uint8{pointFormatUncompressed},
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secureRenegotiationSupported: true,
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alpnProtocols: config.NextProtos,
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supportedVersions: supportedVersions,
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}
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if c.handshakes > 0 {
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hello.secureRenegotiation = c.clientFinished[:]
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}
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preferenceOrder := cipherSuitesPreferenceOrder
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if !hasAESGCMHardwareSupport {
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preferenceOrder = cipherSuitesPreferenceOrderNoAES
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}
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configCipherSuites := config.cipherSuites()
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hello.cipherSuites = make([]uint16, 0, len(configCipherSuites))
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for _, suiteId := range preferenceOrder {
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suite := mutualCipherSuite(configCipherSuites, suiteId)
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if suite == nil {
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continue
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}
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// Don't advertise TLS 1.2-only cipher suites unless
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// we're attempting TLS 1.2.
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if hello.vers < VersionTLS12 && suite.flags&suiteTLS12 != 0 {
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continue
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}
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hello.cipherSuites = append(hello.cipherSuites, suiteId)
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}
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_, err := io.ReadFull(config.rand(), hello.random)
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if err != nil {
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return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
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}
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// A random session ID is used to detect when the server accepted a ticket
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// and is resuming a session (see RFC 5077). In TLS 1.3, it's always set as
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// a compatibility measure (see RFC 8446, Section 4.1.2).
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if c.extraConfig == nil || c.extraConfig.AlternativeRecordLayer == nil {
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hello.sessionId = make([]byte, 32)
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if _, err := io.ReadFull(config.rand(), hello.sessionId); err != nil {
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return nil, nil, errors.New("tls: short read from Rand: " + err.Error())
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}
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}
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if hello.vers >= VersionTLS12 {
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hello.supportedSignatureAlgorithms = supportedSignatureAlgorithms()
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}
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if testingOnlyForceClientHelloSignatureAlgorithms != nil {
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hello.supportedSignatureAlgorithms = testingOnlyForceClientHelloSignatureAlgorithms
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}
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var key *ecdh.PrivateKey
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if hello.supportedVersions[0] == VersionTLS13 {
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if len(hello.supportedVersions) == 1 {
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hello.cipherSuites = hello.cipherSuites[:0]
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}
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if hasAESGCMHardwareSupport {
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hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13...)
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} else {
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hello.cipherSuites = append(hello.cipherSuites, defaultCipherSuitesTLS13NoAES...)
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}
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curveID := config.curvePreferences()[0]
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if _, ok := curveForCurveID(curveID); !ok {
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return nil, nil, errors.New("tls: CurvePreferences includes unsupported curve")
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}
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key, err = generateECDHEKey(config.rand(), curveID)
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if err != nil {
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return nil, nil, err
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}
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hello.keyShares = []keyShare{{group: curveID, data: key.PublicKey().Bytes()}}
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}
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if hello.supportedVersions[0] == VersionTLS13 && c.extraConfig != nil && c.extraConfig.GetExtensions != nil {
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hello.additionalExtensions = c.extraConfig.GetExtensions(typeClientHello)
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}
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return hello, key, nil
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}
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func (c *Conn) clientHandshake(ctx context.Context) (err error) {
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if c.config == nil {
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c.config = fromConfig(defaultConfig())
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}
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c.setAlternativeRecordLayer()
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// This may be a renegotiation handshake, in which case some fields
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// need to be reset.
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c.didResume = false
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hello, ecdheKey, err := c.makeClientHello()
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if err != nil {
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return err
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}
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c.serverName = hello.serverName
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cacheKey, session, earlySecret, binderKey, err := c.loadSession(hello)
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if err != nil {
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return err
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}
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if cacheKey != "" && session != nil {
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var deletedTicket bool
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if session.vers == VersionTLS13 && hello.earlyData && c.extraConfig != nil && c.extraConfig.Enable0RTT {
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// don't reuse a session ticket that enabled 0-RTT
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c.config.ClientSessionCache.Put(cacheKey, nil)
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deletedTicket = true
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if suite := cipherSuiteTLS13ByID(session.cipherSuite); suite != nil {
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h := suite.hash.New()
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helloBytes, err := hello.marshal()
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if err != nil {
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return err
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}
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h.Write(helloBytes)
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clientEarlySecret := suite.deriveSecret(earlySecret, "c e traffic", h)
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c.out.exportKey(Encryption0RTT, suite, clientEarlySecret)
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if err := c.config.writeKeyLog(keyLogLabelEarlyTraffic, hello.random, clientEarlySecret); err != nil {
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return err
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}
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}
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}
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if !deletedTicket {
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defer func() {
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// If we got a handshake failure when resuming a session, throw away
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// the session ticket. See RFC 5077, Section 3.2.
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//
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// RFC 8446 makes no mention of dropping tickets on failure, but it
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// does require servers to abort on invalid binders, so we need to
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// delete tickets to recover from a corrupted PSK.
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if err != nil {
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c.config.ClientSessionCache.Put(cacheKey, nil)
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}
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}()
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}
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}
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if _, err := c.writeHandshakeRecord(hello, nil); err != nil {
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return err
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}
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// serverHelloMsg is not included in the transcript
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msg, err := c.readHandshake(nil)
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if err != nil {
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return err
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}
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serverHello, ok := msg.(*serverHelloMsg)
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if !ok {
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c.sendAlert(alertUnexpectedMessage)
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return unexpectedMessageError(serverHello, msg)
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}
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if err := c.pickTLSVersion(serverHello); err != nil {
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return err
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}
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// If we are negotiating a protocol version that's lower than what we
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// support, check for the server downgrade canaries.
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// See RFC 8446, Section 4.1.3.
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maxVers := c.config.maxSupportedVersion(roleClient)
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tls12Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS12
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tls11Downgrade := string(serverHello.random[24:]) == downgradeCanaryTLS11
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if maxVers == VersionTLS13 && c.vers <= VersionTLS12 && (tls12Downgrade || tls11Downgrade) ||
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maxVers == VersionTLS12 && c.vers <= VersionTLS11 && tls11Downgrade {
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c.sendAlert(alertIllegalParameter)
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return errors.New("tls: downgrade attempt detected, possibly due to a MitM attack or a broken middlebox")
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}
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if c.vers == VersionTLS13 {
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hs := &clientHandshakeStateTLS13{
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c: c,
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ctx: ctx,
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serverHello: serverHello,
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hello: hello,
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ecdheKey: ecdheKey,
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session: session,
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earlySecret: earlySecret,
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binderKey: binderKey,
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}
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// In TLS 1.3, session tickets are delivered after the handshake.
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return hs.handshake()
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}
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hs := &clientHandshakeState{
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c: c,
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ctx: ctx,
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serverHello: serverHello,
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hello: hello,
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session: session,
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}
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if err := hs.handshake(); err != nil {
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return err
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}
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// If we had a successful handshake and hs.session is different from
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// the one already cached - cache a new one.
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if cacheKey != "" && hs.session != nil && session != hs.session {
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c.config.ClientSessionCache.Put(cacheKey, toClientSessionState(hs.session))
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}
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c.updateConnectionState()
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return nil
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}
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// extract the app data saved in the session.nonce,
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// and set the session.nonce to the actual nonce value
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func (c *Conn) decodeSessionState(session *clientSessionState) (uint32 /* max early data */, []byte /* app data */, bool /* ok */) {
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s := cryptobyte.String(session.nonce)
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var version uint16
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if !s.ReadUint16(&version) {
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return 0, nil, false
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}
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if version != clientSessionStateVersion {
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return 0, nil, false
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}
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var maxEarlyData uint32
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if !s.ReadUint32(&maxEarlyData) {
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return 0, nil, false
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}
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var appData []byte
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if !readUint16LengthPrefixed(&s, &appData) {
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return 0, nil, false
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}
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var nonce []byte
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if !readUint16LengthPrefixed(&s, &nonce) {
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return 0, nil, false
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}
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session.nonce = nonce
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return maxEarlyData, appData, true
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}
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func (c *Conn) loadSession(hello *clientHelloMsg) (cacheKey string,
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session *clientSessionState, earlySecret, binderKey []byte, err error) {
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if c.config.SessionTicketsDisabled || c.config.ClientSessionCache == nil {
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return "", nil, nil, nil, nil
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}
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hello.ticketSupported = true
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if hello.supportedVersions[0] == VersionTLS13 {
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// Require DHE on resumption as it guarantees forward secrecy against
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// compromise of the session ticket key. See RFC 8446, Section 4.2.9.
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hello.pskModes = []uint8{pskModeDHE}
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}
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// Session resumption is not allowed if renegotiating because
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// renegotiation is primarily used to allow a client to send a client
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// certificate, which would be skipped if session resumption occurred.
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if c.handshakes != 0 {
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return "", nil, nil, nil, nil
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}
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// Try to resume a previously negotiated TLS session, if available.
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cacheKey = clientSessionCacheKey(c.conn.RemoteAddr(), c.config)
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sess, ok := c.config.ClientSessionCache.Get(cacheKey)
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if !ok || sess == nil {
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return cacheKey, nil, nil, nil, nil
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}
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session = fromClientSessionState(sess)
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var appData []byte
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var maxEarlyData uint32
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if session.vers == VersionTLS13 {
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var ok bool
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maxEarlyData, appData, ok = c.decodeSessionState(session)
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if !ok { // delete it, if parsing failed
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c.config.ClientSessionCache.Put(cacheKey, nil)
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return cacheKey, nil, nil, nil, nil
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}
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}
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// Check that version used for the previous session is still valid.
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versOk := false
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for _, v := range hello.supportedVersions {
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if v == session.vers {
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versOk = true
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break
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}
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}
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if !versOk {
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return cacheKey, nil, nil, nil, nil
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}
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// Check that the cached server certificate is not expired, and that it's
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// valid for the ServerName. This should be ensured by the cache key, but
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// protect the application from a faulty ClientSessionCache implementation.
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if !c.config.InsecureSkipVerify {
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if len(session.verifiedChains) == 0 {
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// The original connection had InsecureSkipVerify, while this doesn't.
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return cacheKey, nil, nil, nil, nil
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}
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serverCert := session.serverCertificates[0]
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if c.config.time().After(serverCert.NotAfter) {
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// Expired certificate, delete the entry.
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c.config.ClientSessionCache.Put(cacheKey, nil)
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return cacheKey, nil, nil, nil, nil
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}
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if err := serverCert.VerifyHostname(c.config.ServerName); err != nil {
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return cacheKey, nil, nil, nil, nil
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}
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}
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if session.vers != VersionTLS13 {
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// In TLS 1.2 the cipher suite must match the resumed session. Ensure we
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// are still offering it.
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if mutualCipherSuite(hello.cipherSuites, session.cipherSuite) == nil {
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return cacheKey, nil, nil, nil, nil
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}
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hello.sessionTicket = session.sessionTicket
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return
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}
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// Check that the session ticket is not expired.
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if c.config.time().After(session.useBy) {
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c.config.ClientSessionCache.Put(cacheKey, nil)
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return cacheKey, nil, nil, nil, nil
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}
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// In TLS 1.3 the KDF hash must match the resumed session. Ensure we
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// offer at least one cipher suite with that hash.
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cipherSuite := cipherSuiteTLS13ByID(session.cipherSuite)
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if cipherSuite == nil {
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return cacheKey, nil, nil, nil, nil
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}
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cipherSuiteOk := false
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for _, offeredID := range hello.cipherSuites {
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offeredSuite := cipherSuiteTLS13ByID(offeredID)
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if offeredSuite != nil && offeredSuite.hash == cipherSuite.hash {
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cipherSuiteOk = true
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break
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}
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}
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if !cipherSuiteOk {
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return cacheKey, nil, nil, nil, nil
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}
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// Set the pre_shared_key extension. See RFC 8446, Section 4.2.11.1.
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ticketAge := uint32(c.config.time().Sub(session.receivedAt) / time.Millisecond)
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identity := pskIdentity{
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label: session.sessionTicket,
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obfuscatedTicketAge: ticketAge + session.ageAdd,
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}
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hello.pskIdentities = []pskIdentity{identity}
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hello.pskBinders = [][]byte{make([]byte, cipherSuite.hash.Size())}
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// Compute the PSK binders. See RFC 8446, Section 4.2.11.2.
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psk := cipherSuite.expandLabel(session.masterSecret, "resumption",
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session.nonce, cipherSuite.hash.Size())
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earlySecret = cipherSuite.extract(psk, nil)
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binderKey = cipherSuite.deriveSecret(earlySecret, resumptionBinderLabel, nil)
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if c.extraConfig != nil {
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hello.earlyData = c.extraConfig.Enable0RTT && maxEarlyData > 0
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}
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transcript := cipherSuite.hash.New()
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helloBytes, err := hello.marshalWithoutBinders()
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if err != nil {
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return "", nil, nil, nil, err
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}
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transcript.Write(helloBytes)
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pskBinders := [][]byte{cipherSuite.finishedHash(binderKey, transcript)}
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if err := hello.updateBinders(pskBinders); err != nil {
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return "", nil, nil, nil, err
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}
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if session.vers == VersionTLS13 && c.extraConfig != nil && c.extraConfig.SetAppDataFromSessionState != nil {
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c.extraConfig.SetAppDataFromSessionState(appData)
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}
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return
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}
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func (c *Conn) pickTLSVersion(serverHello *serverHelloMsg) error {
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peerVersion := serverHello.vers
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if serverHello.supportedVersion != 0 {
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peerVersion = serverHello.supportedVersion
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}
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vers, ok := c.config.mutualVersion(roleClient, []uint16{peerVersion})
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if !ok {
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c.sendAlert(alertProtocolVersion)
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return fmt.Errorf("tls: server selected unsupported protocol version %x", peerVersion)
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}
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c.vers = vers
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c.haveVers = true
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c.in.version = vers
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c.out.version = vers
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return nil
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}
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// Does the handshake, either a full one or resumes old session. Requires hs.c,
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// hs.hello, hs.serverHello, and, optionally, hs.session to be set.
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func (hs *clientHandshakeState) handshake() error {
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c := hs.c
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isResume, err := hs.processServerHello()
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if err != nil {
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return err
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}
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hs.finishedHash = newFinishedHash(c.vers, hs.suite)
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// No signatures of the handshake are needed in a resumption.
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// Otherwise, in a full handshake, if we don't have any certificates
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// configured then we will never send a CertificateVerify message and
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// thus no signatures are needed in that case either.
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if isResume || (len(c.config.Certificates) == 0 && c.config.GetClientCertificate == nil) {
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hs.finishedHash.discardHandshakeBuffer()
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}
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if err := transcriptMsg(hs.hello, &hs.finishedHash); err != nil {
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return err
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}
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if err := transcriptMsg(hs.serverHello, &hs.finishedHash); err != nil {
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return err
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}
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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)
|
|
c.isHandshakeComplete.Store(true)
|
|
|
|
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(&hs.finishedHash)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
certMsg, ok := msg.(*certificateMsg)
|
|
if !ok || len(certMsg.certificates) == 0 {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
return unexpectedMessageError(certMsg, msg)
|
|
}
|
|
|
|
msg, err = c.readHandshake(&hs.finishedHash)
|
|
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")
|
|
}
|
|
|
|
c.ocspResponse = cs.response
|
|
|
|
msg, err = c.readHandshake(&hs.finishedHash)
|
|
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 {
|
|
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(&hs.finishedHash)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
var chainToSend *Certificate
|
|
var certRequested bool
|
|
certReq, ok := msg.(*certificateRequestMsg)
|
|
if ok {
|
|
certRequested = true
|
|
|
|
cri := certificateRequestInfoFromMsg(hs.ctx, c.vers, certReq)
|
|
if chainToSend, err = c.getClientCertificate(cri); err != nil {
|
|
c.sendAlert(alertInternalError)
|
|
return err
|
|
}
|
|
|
|
msg, err = c.readHandshake(&hs.finishedHash)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
shd, ok := msg.(*serverHelloDoneMsg)
|
|
if !ok {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
return unexpectedMessageError(shd, msg)
|
|
}
|
|
|
|
// 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
|
|
if _, err := hs.c.writeHandshakeRecord(certMsg, &hs.finishedHash); 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 {
|
|
if _, err := hs.c.writeHandshakeRecord(ckx, &hs.finishedHash); 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)
|
|
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
|
|
}
|
|
|
|
if _, err := hs.c.writeHandshakeRecord(certVerify, &hs.finishedHash); 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
|
|
}
|
|
|
|
// finishedMsg is included in the transcript, but not until after we
|
|
// check the client version, since the state before this message was
|
|
// sent is used during verification.
|
|
msg, err := c.readHandshake(nil)
|
|
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")
|
|
}
|
|
|
|
if err := transcriptMsg(serverFinished, &hs.finishedHash); err != nil {
|
|
return err
|
|
}
|
|
|
|
copy(out, verify)
|
|
return nil
|
|
}
|
|
|
|
func (hs *clientHandshakeState) readSessionTicket() error {
|
|
if !hs.serverHello.ticketSupported {
|
|
return nil
|
|
}
|
|
|
|
c := hs.c
|
|
msg, err := c.readHandshake(&hs.finishedHash)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
sessionTicketMsg, ok := msg.(*newSessionTicketMsg)
|
|
if !ok {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
return unexpectedMessageError(sessionTicketMsg, msg)
|
|
}
|
|
|
|
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.writeChangeCipherRecord(); err != nil {
|
|
return err
|
|
}
|
|
|
|
finished := new(finishedMsg)
|
|
finished.verifyData = hs.finishedHash.clientSum(hs.masterSecret)
|
|
if _, err := hs.c.writeHandshakeRecord(finished, &hs.finishedHash); err != nil {
|
|
return err
|
|
}
|
|
copy(out, finished.verifyData)
|
|
return nil
|
|
}
|
|
|
|
// maxRSAKeySize is the maximum RSA key size in bits that we are willing
|
|
// to verify the signatures of during a TLS handshake.
|
|
const maxRSAKeySize = 8192
|
|
|
|
// 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 {
|
|
activeHandles := make([]*activeCert, len(certificates))
|
|
certs := make([]*x509.Certificate, len(certificates))
|
|
for i, asn1Data := range certificates {
|
|
cert, err := clientCertCache.newCert(asn1Data)
|
|
if err != nil {
|
|
c.sendAlert(alertBadCertificate)
|
|
return errors.New("tls: failed to parse certificate from server: " + err.Error())
|
|
}
|
|
if cert.cert.PublicKeyAlgorithm == x509.RSA && cert.cert.PublicKey.(*rsa.PublicKey).N.BitLen() > maxRSAKeySize {
|
|
c.sendAlert(alertBadCertificate)
|
|
return fmt.Errorf("tls: server sent certificate containing RSA key larger than %d bits", maxRSAKeySize)
|
|
}
|
|
activeHandles[i] = cert
|
|
certs[i] = cert.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 &CertificateVerificationError{UnverifiedCertificates: certs, Err: 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.activeCertHandles = activeHandles
|
|
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 toCertificateRequestInfo(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 toCertificateRequestInfo(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
|
|
}
|
|
|
|
const clientSessionCacheKeyPrefix = "qtls-"
|
|
|
|
// 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 clientSessionCacheKeyPrefix + config.ServerName
|
|
}
|
|
return clientSessionCacheKeyPrefix + 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
|
|
}
|