crypto/tls: implement TLS 1.3 version-specific messages

Note that there is significant code duplication due to extensions with
the same format appearing in different messages in TLS 1.3. This will be
cleaned up in a future refactor once CL 145317 is merged.

Enforcing the presence/absence of each extension in each message is left
to the upper layer, based on both protocol version and extensions
advertised in CH and CR. Duplicated extensions and unknown extensions in
SH, EE, HRR, and CT will be tightened up in a future CL.

The TLS 1.2 CertificateStatus message was restricted to accepting only
type OCSP as any other type (none of which are specified so far) would
have to be negotiated.

Updates #9671

Change-Id: I7c42394c5cc0af01faa84b9b9f25fdc6e7cfbb9e
Reviewed-on: https://go-review.googlesource.com/c/145477
Reviewed-by: Adam Langley <agl@golang.org>

src/crypto/tls/common.go

@@ -56,19 +56,23 @@ const (
 
 // TLS handshake message types.
 const (
-	typeHelloRequest       uint8 = 0
-	typeClientHello        uint8 = 1
-	typeServerHello        uint8 = 2
-	typeNewSessionTicket   uint8 = 4
-	typeCertificate        uint8 = 11
-	typeServerKeyExchange  uint8 = 12
-	typeCertificateRequest uint8 = 13
-	typeServerHelloDone    uint8 = 14
-	typeCertificateVerify  uint8 = 15
-	typeClientKeyExchange  uint8 = 16
-	typeFinished           uint8 = 20
-	typeCertificateStatus  uint8 = 22
-	typeNextProtocol       uint8 = 67 // Not IANA assigned
+	typeHelloRequest        uint8 = 0
+	typeClientHello         uint8 = 1
+	typeServerHello         uint8 = 2
+	typeNewSessionTicket    uint8 = 4
+	typeEndOfEarlyData      uint8 = 5
+	typeEncryptedExtensions uint8 = 8
+	typeCertificate         uint8 = 11
+	typeServerKeyExchange   uint8 = 12
+	typeCertificateRequest  uint8 = 13
+	typeServerHelloDone     uint8 = 14
+	typeCertificateVerify   uint8 = 15
+	typeClientKeyExchange   uint8 = 16
+	typeFinished            uint8 = 20
+	typeCertificateStatus   uint8 = 22
+	typeKeyUpdate           uint8 = 24
+	typeNextProtocol        uint8 = 67  // Not IANA assigned
+	typeMessageHash         uint8 = 254 // synthetic message
 )
 
 // TLS compression types.
@@ -87,6 +91,7 @@ const (
 	extensionSCT                     uint16 = 18
 	extensionSessionTicket           uint16 = 35
 	extensionPreSharedKey            uint16 = 41
+	extensionEarlyData               uint16 = 42
 	extensionSupportedVersions       uint16 = 43
 	extensionCookie                  uint16 = 44
 	extensionPSKModes                uint16 = 45

src/crypto/tls/conn.go

@@ -990,12 +990,24 @@ func (c *Conn) readHandshake() (interface{}, error) {
 	case typeServerHello:
 		m = new(serverHelloMsg)
 	case typeNewSessionTicket:
-		m = new(newSessionTicketMsg)
+		if c.vers == VersionTLS13 {
+			m = new(newSessionTicketMsgTLS13)
+		} else {
+			m = new(newSessionTicketMsg)
+		}
 	case typeCertificate:
-		m = new(certificateMsg)
+		if c.vers == VersionTLS13 {
+			m = new(certificateMsgTLS13)
+		} else {
+			m = new(certificateMsg)
+		}
 	case typeCertificateRequest:
-		m = &certificateRequestMsg{
-			hasSignatureAlgorithm: c.vers >= VersionTLS12,
+		if c.vers == VersionTLS13 {
+			m = new(certificateRequestMsgTLS13)
+		} else {
+			m = &certificateRequestMsg{
+				hasSignatureAlgorithm: c.vers >= VersionTLS12,
+			}
 		}
 	case typeCertificateStatus:
 		m = new(certificateStatusMsg)
@@ -1013,6 +1025,12 @@ func (c *Conn) readHandshake() (interface{}, error) {
 		m = new(nextProtoMsg)
 	case typeFinished:
 		m = new(finishedMsg)
+	case typeEncryptedExtensions:
+		m = new(encryptedExtensionsMsg)
+	case typeEndOfEarlyData:
+		m = new(endOfEarlyDataMsg)
+	case typeKeyUpdate:
+		m = new(keyUpdateMsg)
 	default:
 		return nil, c.in.setErrorLocked(c.sendAlert(alertUnexpectedMessage))
 	}

src/crypto/tls/handshake_client.go

@@ -393,9 +393,7 @@ func (hs *clientHandshakeState) doFullHandshake() error {
 		}
 		hs.finishedHash.Write(cs.marshal())
 
-		if cs.statusType == statusTypeOCSP {
-			c.ocspResponse = cs.response
-		}
+		c.ocspResponse = cs.response
 
 		msg, err = c.readHandshake()
 		if err != nil {

src/crypto/tls/handshake_messages.go

@@ -71,6 +71,7 @@ type clientHelloMsg struct {
 	supportedVersions                []uint16
 	cookie                           []byte
 	keyShares                        []keyShare
+	earlyData                        bool
 	pskModes                         []uint8
 	pskIdentities                    []pskIdentity
 	pskBinders                       [][]byte
@@ -239,6 +240,11 @@ func (m *clientHelloMsg) marshal() []byte {
 					})
 				})
 			}
+			if m.earlyData {
+				// RFC 8446, Section 4.2.10
+				b.AddUint16(extensionEarlyData)
+				b.AddUint16(0) // empty extension_data
+			}
 			if len(m.pskModes) > 0 {
 				// RFC 8446, Section 4.2.9
 				b.AddUint16(extensionPSKModes)
@@ -478,6 +484,9 @@ func (m *clientHelloMsg) unmarshal(data []byte) bool {
 				}
 				m.keyShares = append(m.keyShares, ks)
 			}
+		case extensionEarlyData:
+			// RFC 8446, Section 4.2.10
+			m.earlyData = true
 		case extensionPSKModes:
 			// RFC 8446, Section 4.2.9
 			if !readUint8LengthPrefixed(&extData, &m.pskModes) {
@@ -782,6 +791,342 @@ func (m *serverHelloMsg) unmarshal(data []byte) bool {
 	return true
 }
 
+type encryptedExtensionsMsg struct {
+	raw          []byte
+	alpnProtocol string
+}
+
+func (m *encryptedExtensionsMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeEncryptedExtensions)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if len(m.alpnProtocol) > 0 {
+				b.AddUint16(extensionALPN)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddBytes([]byte(m.alpnProtocol))
+						})
+					})
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *encryptedExtensionsMsg) unmarshal(data []byte) bool {
+	*m = encryptedExtensionsMsg{raw: data}
+	s := cryptobyte.String(data)
+
+	var extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint16LengthPrefixed(&extensions) || !s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionALPN:
+			var protoList cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&protoList) || protoList.Empty() {
+				return false
+			}
+			var proto cryptobyte.String
+			if !protoList.ReadUint8LengthPrefixed(&proto) ||
+				proto.Empty() || !protoList.Empty() {
+				return false
+			}
+			m.alpnProtocol = string(proto)
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type endOfEarlyDataMsg struct{}
+
+func (m *endOfEarlyDataMsg) marshal() []byte {
+	x := make([]byte, 4)
+	x[0] = typeEndOfEarlyData
+	return x
+}
+
+func (m *endOfEarlyDataMsg) unmarshal(data []byte) bool {
+	return len(data) == 4
+}
+
+type keyUpdateMsg struct {
+	raw             []byte
+	updateRequested bool
+}
+
+func (m *keyUpdateMsg) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeKeyUpdate)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		if m.updateRequested {
+			b.AddUint8(1)
+		} else {
+			b.AddUint8(0)
+		}
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *keyUpdateMsg) unmarshal(data []byte) bool {
+	m.raw = data
+	s := cryptobyte.String(data)
+
+	var updateRequested uint8
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8(&updateRequested) || !s.Empty() {
+		return false
+	}
+	switch updateRequested {
+	case 0:
+		m.updateRequested = false
+	case 1:
+		m.updateRequested = true
+	default:
+		return false
+	}
+	return true
+}
+
+type newSessionTicketMsgTLS13 struct {
+	raw          []byte
+	lifetime     uint32
+	ageAdd       uint32
+	nonce        []byte
+	label        []byte
+	maxEarlyData uint32
+}
+
+func (m *newSessionTicketMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeNewSessionTicket)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint32(m.lifetime)
+		b.AddUint32(m.ageAdd)
+		b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.nonce)
+		})
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.label)
+		})
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.maxEarlyData > 0 {
+				b.AddUint16(extensionEarlyData)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint32(m.maxEarlyData)
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *newSessionTicketMsgTLS13) unmarshal(data []byte) bool {
+	*m = newSessionTicketMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint32(&m.lifetime) ||
+		!s.ReadUint32(&m.ageAdd) ||
+		!readUint8LengthPrefixed(&s, &m.nonce) ||
+		!readUint16LengthPrefixed(&s, &m.label) ||
+		!s.ReadUint16LengthPrefixed(&extensions) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionEarlyData:
+			if !extData.ReadUint32(&m.maxEarlyData) {
+				return false
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
+type certificateRequestMsgTLS13 struct {
+	raw                              []byte
+	ocspStapling                     bool
+	scts                             bool
+	supportedSignatureAlgorithms     []SignatureScheme
+	supportedSignatureAlgorithmsCert []SignatureScheme
+}
+
+func (m *certificateRequestMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificateRequest)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		// certificate_request_context (SHALL be zero length unless used for
+		// post-handshake authentication)
+		b.AddUint8(0)
+
+		b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+			if m.ocspStapling {
+				b.AddUint16(extensionStatusRequest)
+				b.AddUint16(0) // empty extension_data
+			}
+			if m.scts {
+				// RFC 8446, Section 4.4.2.1 makes no mention of
+				// signed_certificate_timestamp in CertificateRequest, but
+				// "Extensions in the Certificate message from the client MUST
+				// correspond to extensions in the CertificateRequest message
+				// from the server." and it appears in the table in Section 4.2.
+				b.AddUint16(extensionSCT)
+				b.AddUint16(0) // empty extension_data
+			}
+			if len(m.supportedSignatureAlgorithms) > 0 {
+				b.AddUint16(extensionSignatureAlgorithms)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithms {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+			if len(m.supportedSignatureAlgorithmsCert) > 0 {
+				b.AddUint16(extensionSignatureAlgorithmsCert)
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+						for _, sigAlgo := range m.supportedSignatureAlgorithmsCert {
+							b.AddUint16(uint16(sigAlgo))
+						}
+					})
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *certificateRequestMsgTLS13) unmarshal(data []byte) bool {
+	*m = certificateRequestMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var context, extensions cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
+		!s.ReadUint16LengthPrefixed(&extensions) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !extensions.Empty() {
+		var extension uint16
+		var extData cryptobyte.String
+		if !extensions.ReadUint16(&extension) ||
+			!extensions.ReadUint16LengthPrefixed(&extData) {
+			return false
+		}
+
+		switch extension {
+		case extensionStatusRequest:
+			m.ocspStapling = true
+		case extensionSCT:
+			m.scts = true
+		case extensionSignatureAlgorithms:
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithms = append(
+					m.supportedSignatureAlgorithms, SignatureScheme(sigAndAlg))
+			}
+		case extensionSignatureAlgorithmsCert:
+			var sigAndAlgs cryptobyte.String
+			if !extData.ReadUint16LengthPrefixed(&sigAndAlgs) || sigAndAlgs.Empty() {
+				return false
+			}
+			for !sigAndAlgs.Empty() {
+				var sigAndAlg uint16
+				if !sigAndAlgs.ReadUint16(&sigAndAlg) {
+					return false
+				}
+				m.supportedSignatureAlgorithmsCert = append(
+					m.supportedSignatureAlgorithmsCert, SignatureScheme(sigAndAlg))
+			}
+		default:
+			// Ignore unknown extensions.
+			continue
+		}
+
+		if !extData.Empty() {
+			return false
+		}
+	}
+
+	return true
+}
+
 type certificateMsg struct {
 	raw          []byte
 	certificates [][]byte
@@ -859,6 +1204,131 @@ func (m *certificateMsg) unmarshal(data []byte) bool {
 	return true
 }
 
+type certificateMsgTLS13 struct {
+	raw          []byte
+	certificate  Certificate
+	ocspStapling bool
+	scts         bool
+}
+
+func (m *certificateMsgTLS13) marshal() []byte {
+	if m.raw != nil {
+		return m.raw
+	}
+
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificate)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint8(0) // certificate_request_context
+		b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+			for i, cert := range m.certificate.Certificate {
+				b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+					b.AddBytes(cert)
+				})
+				b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+					if i > 0 {
+						// This library only supports OCSP and SCT for leaf certificates.
+						return
+					}
+					if m.ocspStapling {
+						b.AddUint16(extensionStatusRequest)
+						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddUint8(statusTypeOCSP)
+							b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+								b.AddBytes(m.certificate.OCSPStaple)
+							})
+						})
+					}
+					if m.scts {
+						b.AddUint16(extensionSCT)
+						b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+							b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+								for _, sct := range m.certificate.SignedCertificateTimestamps {
+									b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+										b.AddBytes(sct)
+									})
+								}
+							})
+						})
+					}
+				})
+			}
+		})
+	})
+
+	m.raw = b.BytesOrPanic()
+	return m.raw
+}
+
+func (m *certificateMsgTLS13) unmarshal(data []byte) bool {
+	*m = certificateMsgTLS13{raw: data}
+	s := cryptobyte.String(data)
+
+	var context, certList cryptobyte.String
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8LengthPrefixed(&context) || !context.Empty() ||
+		!s.ReadUint24LengthPrefixed(&certList) ||
+		!s.Empty() {
+		return false
+	}
+
+	for !certList.Empty() {
+		var cert []byte
+		var extensions cryptobyte.String
+		if !readUint24LengthPrefixed(&certList, &cert) ||
+			!certList.ReadUint16LengthPrefixed(&extensions) {
+			return false
+		}
+		m.certificate.Certificate = append(m.certificate.Certificate, cert)
+		for !extensions.Empty() {
+			var extension uint16
+			var extData cryptobyte.String
+			if !extensions.ReadUint16(&extension) ||
+				!extensions.ReadUint16LengthPrefixed(&extData) {
+				return false
+			}
+			if len(m.certificate.Certificate) > 1 {
+				// This library only supports OCSP and SCT for leaf certificates.
+				continue
+			}
+
+			switch extension {
+			case extensionStatusRequest:
+				m.ocspStapling = true
+				var statusType uint8
+				if !extData.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
+					!readUint24LengthPrefixed(&extData, &m.certificate.OCSPStaple) ||
+					len(m.certificate.OCSPStaple) == 0 {
+					return false
+				}
+			case extensionSCT:
+				m.scts = true
+				var sctList cryptobyte.String
+				if !extData.ReadUint16LengthPrefixed(&sctList) || sctList.Empty() {
+					return false
+				}
+				for !sctList.Empty() {
+					var sct []byte
+					if !readUint16LengthPrefixed(&sctList, &sct) ||
+						len(sct) == 0 {
+						return false
+					}
+					m.certificate.SignedCertificateTimestamps = append(
+						m.certificate.SignedCertificateTimestamps, sct)
+				}
+			default:
+				// Ignore unknown extensions.
+				continue
+			}
+
+			if !extData.Empty() {
+				return false
+			}
+		}
+	}
+	return true
+}
+
 type serverKeyExchangeMsg struct {
 	raw []byte
 	key []byte
@@ -890,9 +1360,8 @@ func (m *serverKeyExchangeMsg) unmarshal(data []byte) bool {
 }
 
 type certificateStatusMsg struct {
-	raw        []byte
-	statusType uint8
-	response   []byte
+	raw      []byte
+	response []byte
 }
 
 func (m *certificateStatusMsg) marshal() []byte {
@@ -900,46 +1369,29 @@ func (m *certificateStatusMsg) marshal() []byte {
 		return m.raw
 	}
 
-	var x []byte
-	if m.statusType == statusTypeOCSP {
-		x = make([]byte, 4+4+len(m.response))
-		x[0] = typeCertificateStatus
-		l := len(m.response) + 4
-		x[1] = byte(l >> 16)
-		x[2] = byte(l >> 8)
-		x[3] = byte(l)
-		x[4] = statusTypeOCSP
+	var b cryptobyte.Builder
+	b.AddUint8(typeCertificateStatus)
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddUint8(statusTypeOCSP)
+		b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+			b.AddBytes(m.response)
+		})
+	})
 
-		l -= 4
-		x[5] = byte(l >> 16)
-		x[6] = byte(l >> 8)
-		x[7] = byte(l)
-		copy(x[8:], m.response)
-	} else {
-		x = []byte{typeCertificateStatus, 0, 0, 1, m.statusType}
-	}
-
-	m.raw = x
-	return x
+	m.raw = b.BytesOrPanic()
+	return m.raw
 }
 
 func (m *certificateStatusMsg) unmarshal(data []byte) bool {
 	m.raw = data
-	if len(data) < 5 {
-		return false
-	}
-	m.statusType = data[4]
+	s := cryptobyte.String(data)
 
-	m.response = nil
-	if m.statusType == statusTypeOCSP {
-		if len(data) < 8 {
-			return false
-		}
-		respLen := uint32(data[5])<<16 | uint32(data[6])<<8 | uint32(data[7])
-		if uint32(len(data)) != 4+4+respLen {
-			return false
-		}
-		m.response = data[8:]
+	var statusType uint8
+	if !s.Skip(4) || // message type and uint24 length field
+		!s.ReadUint8(&statusType) || statusType != statusTypeOCSP ||
+		!readUint24LengthPrefixed(&s, &m.response) ||
+		len(m.response) == 0 || !s.Empty() {
+		return false
 	}
 	return true
 }

src/crypto/tls/handshake_messages_test.go

@@ -29,6 +29,12 @@ var tests = []interface{}{
 	&nextProtoMsg{},
 	&newSessionTicketMsg{},
 	&sessionState{},
+	&encryptedExtensionsMsg{},
+	&endOfEarlyDataMsg{},
+	&keyUpdateMsg{},
+	&newSessionTicketMsgTLS13{},
+	&certificateRequestMsgTLS13{},
+	&certificateMsgTLS13{},
 }
 
 func TestMarshalUnmarshal(t *testing.T) {
@@ -184,6 +190,9 @@ func (*clientHelloMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 		m.pskIdentities = append(m.pskIdentities, psk)
 		m.pskBinders = append(m.pskBinders, randomBytes(rand.Intn(50)+32, rand))
 	}
+	if rand.Intn(10) > 5 {
+		m.earlyData = true
+	}
 
 	return reflect.ValueOf(m)
 }
@@ -209,7 +218,9 @@ func (*serverHelloMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 	if rand.Intn(10) > 5 {
 		m.ticketSupported = true
 	}
-	m.alpnProtocol = randomString(rand.Intn(32)+1, rand)
+	if rand.Intn(10) > 5 {
+		m.alpnProtocol = randomString(rand.Intn(32)+1, rand)
+	}
 
 	for i := 0; i < rand.Intn(4); i++ {
 		m.scts = append(m.scts, randomBytes(rand.Intn(500)+1, rand))
@@ -241,6 +252,16 @@ func (*serverHelloMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 	return reflect.ValueOf(m)
 }
 
+func (*encryptedExtensionsMsg) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &encryptedExtensionsMsg{}
+
+	if rand.Intn(10) > 5 {
+		m.alpnProtocol = randomString(rand.Intn(32)+1, rand)
+	}
+
+	return reflect.ValueOf(m)
+}
+
 func (*certificateMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 	m := &certificateMsg{}
 	numCerts := rand.Intn(20)
@@ -270,12 +291,7 @@ func (*certificateVerifyMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 
 func (*certificateStatusMsg) Generate(rand *rand.Rand, size int) reflect.Value {
 	m := &certificateStatusMsg{}
-	if rand.Intn(10) > 5 {
-		m.statusType = statusTypeOCSP
-		m.response = randomBytes(rand.Intn(10)+1, rand)
-	} else {
-		m.statusType = 42
-	}
+	m.response = randomBytes(rand.Intn(10)+1, rand)
 	return reflect.ValueOf(m)
 }
 
@@ -316,6 +332,66 @@ func (*sessionState) Generate(rand *rand.Rand, size int) reflect.Value {
 	return reflect.ValueOf(s)
 }
 
+func (*endOfEarlyDataMsg) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &endOfEarlyDataMsg{}
+	return reflect.ValueOf(m)
+}
+
+func (*keyUpdateMsg) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &keyUpdateMsg{}
+	m.updateRequested = rand.Intn(10) > 5
+	return reflect.ValueOf(m)
+}
+
+func (*newSessionTicketMsgTLS13) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &newSessionTicketMsgTLS13{}
+	m.lifetime = uint32(rand.Intn(500000))
+	m.ageAdd = uint32(rand.Intn(500000))
+	m.nonce = randomBytes(rand.Intn(100), rand)
+	m.label = randomBytes(rand.Intn(1000), rand)
+	if rand.Intn(10) > 5 {
+		m.maxEarlyData = uint32(rand.Intn(500000))
+	}
+	return reflect.ValueOf(m)
+}
+
+func (*certificateRequestMsgTLS13) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &certificateRequestMsgTLS13{}
+	if rand.Intn(10) > 5 {
+		m.ocspStapling = true
+	}
+	if rand.Intn(10) > 5 {
+		m.scts = true
+	}
+	if rand.Intn(10) > 5 {
+		m.supportedSignatureAlgorithms = supportedSignatureAlgorithms
+	}
+	if rand.Intn(10) > 5 {
+		m.supportedSignatureAlgorithmsCert = supportedSignatureAlgorithms
+	}
+	return reflect.ValueOf(m)
+}
+
+func (*certificateMsgTLS13) Generate(rand *rand.Rand, size int) reflect.Value {
+	m := &certificateMsgTLS13{}
+	for i := 0; i < rand.Intn(2)+1; i++ {
+		m.certificate.Certificate = append(
+			m.certificate.Certificate, randomBytes(rand.Intn(500)+1, rand))
+	}
+	if rand.Intn(10) > 5 {
+		m.ocspStapling = true
+		m.certificate.OCSPStaple = randomBytes(rand.Intn(100)+1, rand)
+	}
+	if rand.Intn(10) > 5 {
+		m.scts = true
+		for i := 0; i < rand.Intn(2)+1; i++ {
+			m.certificate.SignedCertificateTimestamps = append(
+				m.certificate.SignedCertificateTimestamps, randomBytes(rand.Intn(500)+1, rand))
+		}
+	}
+	return reflect.ValueOf(m)
+}
+
 func TestRejectEmptySCTList(t *testing.T) {
 	// RFC 6962, Section 3.3.1 specifies that empty SCT lists are invalid.
 

src/crypto/tls/handshake_server.go

@@ -389,7 +389,6 @@ func (hs *serverHandshakeState) doFullHandshake() error {
 
 	if hs.hello.ocspStapling {
 		certStatus := new(certificateStatusMsg)
-		certStatus.statusType = statusTypeOCSP
 		certStatus.response = hs.cert.OCSPStaple
 		hs.finishedHash.Write(certStatus.marshal())
 		if _, err := c.writeRecord(recordTypeHandshake, certStatus.marshal()); err != nil {