| // 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 "strings" |
| |
| type clientHelloMsg struct { |
| raw []byte |
| major, minor uint8 |
| random []byte |
| sessionId []byte |
| cipherSuites []uint16 |
| compressionMethods []uint8 |
| nextProtoNeg bool |
| serverName string |
| } |
| |
| func (m *clientHelloMsg) marshal() []byte { |
| if m.raw != nil { |
| return m.raw |
| } |
| |
| length := 2 + 32 + 1 + len(m.sessionId) + 2 + len(m.cipherSuites)*2 + 1 + len(m.compressionMethods) |
| numExtensions := 0 |
| extensionsLength := 0 |
| if m.nextProtoNeg { |
| numExtensions++ |
| } |
| if len(m.serverName) > 0 { |
| extensionsLength += 5 + len(m.serverName) |
| numExtensions++ |
| } |
| if numExtensions > 0 { |
| extensionsLength += 4 * numExtensions |
| length += 2 + extensionsLength |
| } |
| |
| x := make([]byte, 4+length) |
| x[0] = typeClientHello |
| x[1] = uint8(length >> 16) |
| x[2] = uint8(length >> 8) |
| x[3] = uint8(length) |
| x[4] = m.major |
| x[5] = m.minor |
| copy(x[6:38], m.random) |
| x[38] = uint8(len(m.sessionId)) |
| copy(x[39:39+len(m.sessionId)], m.sessionId) |
| y := x[39+len(m.sessionId):] |
| y[0] = uint8(len(m.cipherSuites) >> 7) |
| y[1] = uint8(len(m.cipherSuites) << 1) |
| for i, suite := range m.cipherSuites { |
| y[2+i*2] = uint8(suite >> 8) |
| y[3+i*2] = uint8(suite) |
| } |
| z := y[2+len(m.cipherSuites)*2:] |
| z[0] = uint8(len(m.compressionMethods)) |
| copy(z[1:], m.compressionMethods) |
| |
| z = z[1+len(m.compressionMethods):] |
| if numExtensions > 0 { |
| z[0] = byte(extensionsLength >> 8) |
| z[1] = byte(extensionsLength) |
| z = z[2:] |
| } |
| if m.nextProtoNeg { |
| z[0] = byte(extensionNextProtoNeg >> 8) |
| z[1] = byte(extensionNextProtoNeg) |
| // The length is always 0 |
| z = z[4:] |
| } |
| if len(m.serverName) > 0 { |
| z[0] = byte(extensionServerName >> 8) |
| z[1] = byte(extensionServerName) |
| l := len(m.serverName) + 5 |
| z[2] = byte(l >> 8) |
| z[3] = byte(l) |
| z = z[4:] |
| |
| // RFC 3546, section 3.1 |
| // |
| // struct { |
| // NameType name_type; |
| // select (name_type) { |
| // case host_name: HostName; |
| // } name; |
| // } ServerName; |
| // |
| // enum { |
| // host_name(0), (255) |
| // } NameType; |
| // |
| // opaque HostName<1..2^16-1>; |
| // |
| // struct { |
| // ServerName server_name_list<1..2^16-1> |
| // } ServerNameList; |
| |
| z[1] = 1 |
| z[3] = byte(len(m.serverName) >> 8) |
| z[4] = byte(len(m.serverName)) |
| copy(z[5:], strings.Bytes(m.serverName)) |
| z = z[l:] |
| } |
| |
| m.raw = x |
| |
| return x |
| } |
| |
| func (m *clientHelloMsg) unmarshal(data []byte) bool { |
| if len(data) < 43 { |
| return false |
| } |
| m.raw = data |
| m.major = data[4] |
| m.minor = data[5] |
| m.random = data[6:38] |
| sessionIdLen := int(data[38]) |
| if sessionIdLen > 32 || len(data) < 39+sessionIdLen { |
| return false |
| } |
| m.sessionId = data[39 : 39+sessionIdLen] |
| data = data[39+sessionIdLen:] |
| if len(data) < 2 { |
| return false |
| } |
| // cipherSuiteLen is the number of bytes of cipher suite numbers. Since |
| // they are uint16s, the number must be even. |
| cipherSuiteLen := int(data[0])<<8 | int(data[1]) |
| if cipherSuiteLen%2 == 1 || len(data) < 2+cipherSuiteLen { |
| return false |
| } |
| numCipherSuites := cipherSuiteLen / 2 |
| m.cipherSuites = make([]uint16, numCipherSuites) |
| for i := 0; i < numCipherSuites; i++ { |
| m.cipherSuites[i] = uint16(data[2+2*i])<<8 | uint16(data[3+2*i]) |
| } |
| data = data[2+cipherSuiteLen:] |
| if len(data) < 2 { |
| return false |
| } |
| compressionMethodsLen := int(data[0]) |
| if len(data) < 1+compressionMethodsLen { |
| return false |
| } |
| m.compressionMethods = data[1 : 1+compressionMethodsLen] |
| |
| data = data[1+compressionMethodsLen:] |
| |
| m.nextProtoNeg = false |
| m.serverName = "" |
| |
| if len(data) == 0 { |
| // ClientHello is optionally followed by extension data |
| return true |
| } |
| if len(data) < 2 { |
| return false |
| } |
| |
| extensionsLength := int(data[0])<<8 | int(data[1]) |
| data = data[2:] |
| if extensionsLength != len(data) { |
| return false |
| } |
| |
| for len(data) != 0 { |
| if len(data) < 4 { |
| return false |
| } |
| extension := uint16(data[0])<<8 | uint16(data[1]) |
| length := int(data[2])<<8 | int(data[3]) |
| data = data[4:] |
| if len(data) < length { |
| return false |
| } |
| |
| switch extension { |
| case extensionServerName: |
| if length < 2 { |
| return false |
| } |
| numNames := int(data[0])<<8 | int(data[1]) |
| d := data[2:] |
| for i := 0; i < numNames; i++ { |
| if len(d) < 3 { |
| return false |
| } |
| nameType := d[0] |
| nameLen := int(d[1])<<8 | int(d[2]) |
| d = d[3:] |
| if len(d) < nameLen { |
| return false |
| } |
| if nameType == 0 { |
| m.serverName = string(d[0:nameLen]) |
| break |
| } |
| d = d[nameLen:] |
| } |
| case extensionNextProtoNeg: |
| if length > 0 { |
| return false |
| } |
| m.nextProtoNeg = true |
| } |
| data = data[length:] |
| } |
| |
| return true |
| } |
| |
| type serverHelloMsg struct { |
| raw []byte |
| major, minor uint8 |
| random []byte |
| sessionId []byte |
| cipherSuite uint16 |
| compressionMethod uint8 |
| nextProtoNeg bool |
| nextProtos []string |
| } |
| |
| func (m *serverHelloMsg) marshal() []byte { |
| if m.raw != nil { |
| return m.raw |
| } |
| |
| length := 38 + len(m.sessionId) |
| numExtensions := 0 |
| extensionsLength := 0 |
| |
| nextProtoLen := 0 |
| if m.nextProtoNeg { |
| numExtensions++ |
| for _, v := range m.nextProtos { |
| nextProtoLen += len(v) |
| } |
| nextProtoLen += len(m.nextProtos) |
| extensionsLength += nextProtoLen |
| } |
| if numExtensions > 0 { |
| extensionsLength += 4 * numExtensions |
| length += 2 + extensionsLength |
| } |
| |
| x := make([]byte, 4+length) |
| x[0] = typeServerHello |
| x[1] = uint8(length >> 16) |
| x[2] = uint8(length >> 8) |
| x[3] = uint8(length) |
| x[4] = m.major |
| x[5] = m.minor |
| copy(x[6:38], m.random) |
| x[38] = uint8(len(m.sessionId)) |
| copy(x[39:39+len(m.sessionId)], m.sessionId) |
| z := x[39+len(m.sessionId):] |
| z[0] = uint8(m.cipherSuite >> 8) |
| z[1] = uint8(m.cipherSuite) |
| z[2] = uint8(m.compressionMethod) |
| |
| z = z[3:] |
| if numExtensions > 0 { |
| z[0] = byte(extensionsLength >> 8) |
| z[1] = byte(extensionsLength) |
| z = z[2:] |
| } |
| if m.nextProtoNeg { |
| z[0] = byte(extensionNextProtoNeg >> 8) |
| z[1] = byte(extensionNextProtoNeg) |
| z[2] = byte(nextProtoLen >> 8) |
| z[3] = byte(nextProtoLen) |
| z = z[4:] |
| |
| for _, v := range m.nextProtos { |
| l := len(v) |
| if l > 255 { |
| l = 255 |
| } |
| z[0] = byte(l) |
| copy(z[1:], strings.Bytes(v[0:l])) |
| z = z[1+l:] |
| } |
| } |
| |
| m.raw = x |
| |
| return x |
| } |
| |
| func append(slice []string, elem string) []string { |
| if len(slice) < cap(slice) { |
| slice = slice[0 : len(slice)+1] |
| slice[len(slice)-1] = elem |
| return slice |
| } |
| |
| fresh := make([]string, len(slice)+1, cap(slice)*2+1) |
| copy(fresh, slice) |
| fresh[len(slice)] = elem |
| return fresh |
| } |
| |
| func (m *serverHelloMsg) unmarshal(data []byte) bool { |
| if len(data) < 42 { |
| return false |
| } |
| m.raw = data |
| m.major = data[4] |
| m.minor = data[5] |
| m.random = data[6:38] |
| sessionIdLen := int(data[38]) |
| if sessionIdLen > 32 || len(data) < 39+sessionIdLen { |
| return false |
| } |
| m.sessionId = data[39 : 39+sessionIdLen] |
| data = data[39+sessionIdLen:] |
| if len(data) < 3 { |
| return false |
| } |
| m.cipherSuite = uint16(data[0])<<8 | uint16(data[1]) |
| m.compressionMethod = data[2] |
| data = data[3:] |
| |
| m.nextProtoNeg = false |
| m.nextProtos = nil |
| |
| if len(data) == 0 { |
| // ServerHello is optionally followed by extension data |
| return true |
| } |
| if len(data) < 2 { |
| return false |
| } |
| |
| extensionsLength := int(data[0])<<8 | int(data[1]) |
| data = data[2:] |
| if len(data) != extensionsLength { |
| return false |
| } |
| |
| for len(data) != 0 { |
| if len(data) < 4 { |
| return false |
| } |
| extension := uint16(data[0])<<8 | uint16(data[1]) |
| length := int(data[2])<<8 | int(data[3]) |
| data = data[4:] |
| if len(data) < length { |
| return false |
| } |
| |
| switch extension { |
| case extensionNextProtoNeg: |
| m.nextProtoNeg = true |
| d := data |
| for len(d) > 0 { |
| l := int(d[0]) |
| d = d[1:] |
| if l == 0 || l > len(d) { |
| return false |
| } |
| m.nextProtos = append(m.nextProtos, string(d[0:l])) |
| d = d[l:] |
| } |
| } |
| data = data[length:] |
| } |
| |
| return true |
| } |
| |
| type certificateMsg struct { |
| raw []byte |
| certificates [][]byte |
| } |
| |
| func (m *certificateMsg) marshal() (x []byte) { |
| if m.raw != nil { |
| return m.raw |
| } |
| |
| var i int |
| for _, slice := range m.certificates { |
| i += len(slice) |
| } |
| |
| length := 3 + 3*len(m.certificates) + i |
| x = make([]byte, 4+length) |
| x[0] = typeCertificate |
| x[1] = uint8(length >> 16) |
| x[2] = uint8(length >> 8) |
| x[3] = uint8(length) |
| |
| certificateOctets := length - 3 |
| x[4] = uint8(certificateOctets >> 16) |
| x[5] = uint8(certificateOctets >> 8) |
| x[6] = uint8(certificateOctets) |
| |
| y := x[7:] |
| for _, slice := range m.certificates { |
| y[0] = uint8(len(slice) >> 16) |
| y[1] = uint8(len(slice) >> 8) |
| y[2] = uint8(len(slice)) |
| copy(y[3:], slice) |
| y = y[3+len(slice):] |
| } |
| |
| m.raw = x |
| return |
| } |
| |
| func (m *certificateMsg) unmarshal(data []byte) bool { |
| if len(data) < 7 { |
| return false |
| } |
| |
| m.raw = data |
| certsLen := uint32(data[4])<<16 | uint32(data[5])<<8 | uint32(data[6]) |
| if uint32(len(data)) != certsLen+7 { |
| return false |
| } |
| |
| numCerts := 0 |
| d := data[7:] |
| for certsLen > 0 { |
| if len(d) < 4 { |
| return false |
| } |
| certLen := uint32(d[0])<<24 | uint32(d[1])<<8 | uint32(d[2]) |
| if uint32(len(d)) < 3+certLen { |
| return false |
| } |
| d = d[3+certLen:] |
| certsLen -= 3 + certLen |
| numCerts++ |
| } |
| |
| m.certificates = make([][]byte, numCerts) |
| d = data[7:] |
| for i := 0; i < numCerts; i++ { |
| certLen := uint32(d[0])<<24 | uint32(d[1])<<8 | uint32(d[2]) |
| m.certificates[i] = d[3 : 3+certLen] |
| d = d[3+certLen:] |
| } |
| |
| return true |
| } |
| |
| type serverHelloDoneMsg struct{} |
| |
| func (m *serverHelloDoneMsg) marshal() []byte { |
| x := make([]byte, 4) |
| x[0] = typeServerHelloDone |
| return x |
| } |
| |
| func (m *serverHelloDoneMsg) unmarshal(data []byte) bool { |
| return len(data) == 4 |
| } |
| |
| type clientKeyExchangeMsg struct { |
| raw []byte |
| ciphertext []byte |
| } |
| |
| func (m *clientKeyExchangeMsg) marshal() []byte { |
| if m.raw != nil { |
| return m.raw |
| } |
| length := len(m.ciphertext) + 2 |
| x := make([]byte, length+4) |
| x[0] = typeClientKeyExchange |
| x[1] = uint8(length >> 16) |
| x[2] = uint8(length >> 8) |
| x[3] = uint8(length) |
| x[4] = uint8(len(m.ciphertext) >> 8) |
| x[5] = uint8(len(m.ciphertext)) |
| copy(x[6:], m.ciphertext) |
| |
| m.raw = x |
| return x |
| } |
| |
| func (m *clientKeyExchangeMsg) unmarshal(data []byte) bool { |
| m.raw = data |
| if len(data) < 7 { |
| return false |
| } |
| cipherTextLen := int(data[4])<<8 | int(data[5]) |
| if len(data) != 6+cipherTextLen { |
| return false |
| } |
| m.ciphertext = data[6:] |
| return true |
| } |
| |
| type finishedMsg struct { |
| raw []byte |
| verifyData []byte |
| } |
| |
| func (m *finishedMsg) marshal() (x []byte) { |
| if m.raw != nil { |
| return m.raw |
| } |
| |
| x = make([]byte, 16) |
| x[0] = typeFinished |
| x[3] = 12 |
| copy(x[4:], m.verifyData) |
| m.raw = x |
| return |
| } |
| |
| func (m *finishedMsg) unmarshal(data []byte) bool { |
| m.raw = data |
| if len(data) != 4+12 { |
| return false |
| } |
| m.verifyData = data[4:] |
| return true |
| } |
| |
| type nextProtoMsg struct { |
| raw []byte |
| proto string |
| } |
| |
| func (m *nextProtoMsg) marshal() []byte { |
| if m.raw != nil { |
| return m.raw |
| } |
| l := len(m.proto) |
| if l > 255 { |
| l = 255 |
| } |
| |
| padding := 32 - (l+2)%32 |
| length := l + padding + 2 |
| x := make([]byte, length+4) |
| x[0] = typeNextProtocol |
| x[1] = uint8(length >> 16) |
| x[2] = uint8(length >> 8) |
| x[3] = uint8(length) |
| |
| y := x[4:] |
| y[0] = byte(l) |
| copy(y[1:], strings.Bytes(m.proto[0:l])) |
| y = y[1+l:] |
| y[0] = byte(padding) |
| |
| m.raw = x |
| |
| return x |
| } |
| |
| func (m *nextProtoMsg) unmarshal(data []byte) bool { |
| m.raw = data |
| |
| if len(data) < 5 { |
| return false |
| } |
| data = data[4:] |
| protoLen := int(data[0]) |
| data = data[1:] |
| if len(data) < protoLen { |
| return false |
| } |
| m.proto = string(data[0:protoLen]) |
| data = data[protoLen:] |
| |
| if len(data) < 1 { |
| return false |
| } |
| paddingLen := int(data[0]) |
| data = data[1:] |
| if len(data) != paddingLen { |
| return false |
| } |
| |
| return true |
| } |
