func (this *SimpleAuthenticator) Open(buffer *alloc.Buffer) bool {
len := buffer.Len()
xtra := 4 - len%4
if xtra != 0 {
buffer.Slice(0, len+xtra)
}
xorbkd(buffer.Value)
if xtra != 0 {
buffer.Slice(0, len)
}
fnvHash := fnv.New32a()
fnvHash.Write(buffer.Value[4:])
if serial.BytesToUint32(buffer.Value[:4]) != fnvHash.Sum32() {
return false
}
length := serial.BytesToUint16(buffer.Value[4:6])
if buffer.Len()-6 != int(length) {
return false
}
buffer.SliceFrom(6)
return true
}
// Open implements cipher.AEAD.Open().
func (v *SimpleAuthenticator) Open(dst, nonce, cipherText, extra []byte) ([]byte, error) {
dst = append(dst, cipherText...)
dstLen := len(dst)
xtra := 4 - dstLen%4
if xtra != 4 {
dst = append(dst, make([]byte, xtra)...)
}
xorbkd(dst)
if xtra != 4 {
dst = dst[:dstLen]
}
fnvHash := fnv.New32a()
fnvHash.Write(dst[4:])
if serial.BytesToUint32(dst[:4]) != fnvHash.Sum32() {
return nil, crypto.ErrAuthenticationFailed
}
length := serial.BytesToUint16(dst[4:6])
if len(dst)-6 != int(length) {
return nil, crypto.ErrAuthenticationFailed
}
return dst[6:], nil
}
func UnmarshalCommand(cmdId byte, data []byte) (protocol.ResponseCommand, error) {
if len(data) <= 4 {
return nil, transport.ErrCorruptedPacket
}
expectedAuth := Authenticate(data[4:])
actualAuth := serial.BytesToUint32(data[:4])
if expectedAuth != actualAuth {
return nil, transport.ErrCorruptedPacket
}
var factory CommandFactory
switch cmdId {
case 1:
factory = new(CommandSwitchAccountFactory)
default:
return nil, ErrUnknownCommand
}
return factory.Unmarshal(data[4:])
}
func UnmarshalCommand(cmdID byte, data []byte) (protocol.ResponseCommand, error) {
if len(data) <= 4 {
return nil, errors.New("VMess|Command: Insufficient length.")
}
expectedAuth := Authenticate(data[4:])
actualAuth := serial.BytesToUint32(data[:4])
if expectedAuth != actualAuth {
return nil, errors.New("VMess|Command: Invalid auth.")
}
var factory CommandFactory
switch cmdID {
case 1:
factory = new(CommandSwitchAccountFactory)
default:
return nil, ErrUnknownCommand
}
return factory.Unmarshal(data[4:])
}
func ReadSegment(buf []byte) (Segment, []byte) {
if len(buf) <= 4 {
return nil, nil
}
conv := serial.BytesToUint16(buf)
buf = buf[2:]
cmd := Command(buf[0])
opt := SegmentOption(buf[1])
buf = buf[2:]
if cmd == CommandData {
seg := NewDataSegment()
seg.Conv = conv
seg.Option = opt
if len(buf) < 16 {
return nil, nil
}
seg.Timestamp = serial.BytesToUint32(buf)
buf = buf[4:]
seg.Number = serial.BytesToUint32(buf)
buf = buf[4:]
seg.SendingNext = serial.BytesToUint32(buf)
buf = buf[4:]
dataLen := int(serial.BytesToUint16(buf))
buf = buf[2:]
if len(buf) < dataLen {
return nil, nil
}
seg.Data = AllocateBuffer().Clear().Append(buf[:dataLen])
buf = buf[dataLen:]
return seg, buf
}
if cmd == CommandACK {
seg := NewAckSegment()
seg.Conv = conv
seg.Option = opt
if len(buf) < 13 {
return nil, nil
}
seg.ReceivingWindow = serial.BytesToUint32(buf)
buf = buf[4:]
seg.ReceivingNext = serial.BytesToUint32(buf)
buf = buf[4:]
seg.Timestamp = serial.BytesToUint32(buf)
buf = buf[4:]
count := int(buf[0])
buf = buf[1:]
if len(buf) < count*4 {
return nil, nil
}
for i := 0; i < count; i++ {
seg.PutNumber(serial.BytesToUint32(buf))
buf = buf[4:]
}
return seg, buf
}
seg := NewCmdOnlySegment()
seg.Conv = conv
seg.Command = cmd
seg.Option = opt
if len(buf) < 12 {
return nil, nil
}
seg.SendingNext = serial.BytesToUint32(buf)
buf = buf[4:]
seg.ReceivinNext = serial.BytesToUint32(buf)
buf = buf[4:]
seg.PeerRTO = serial.BytesToUint32(buf)
buf = buf[4:]
return seg, buf
}
func (this *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.RequestHeader, error) {
buffer := make([]byte, 512)
_, err := io.ReadFull(reader, buffer[:protocol.IDBytesLen])
if err != nil {
log.Info("Raw: Failed to read request header: ", err)
return nil, io.EOF
}
user, timestamp, valid := this.userValidator.Get(buffer[:protocol.IDBytesLen])
if !valid {
return nil, protocol.ErrInvalidUser
}
timestampHash := md5.New()
timestampHash.Write(hashTimestamp(timestamp))
iv := timestampHash.Sum(nil)
account := user.Account.(*vmess.Account)
aesStream := crypto.NewAesDecryptionStream(account.ID.CmdKey(), iv)
decryptor := crypto.NewCryptionReader(aesStream, reader)
nBytes, err := io.ReadFull(decryptor, buffer[:41])
if err != nil {
log.Debug("Raw: Failed to read request header (", nBytes, " bytes): ", err)
return nil, err
}
bufferLen := nBytes
request := &protocol.RequestHeader{
User: user,
Version: buffer[0],
}
if request.Version != Version {
log.Info("Raw: Invalid protocol version ", request.Version)
return nil, protocol.ErrInvalidVersion
}
this.requestBodyIV = append([]byte(nil), buffer[1:17]...) // 16 bytes
this.requestBodyKey = append([]byte(nil), buffer[17:33]...) // 16 bytes
this.responseHeader = buffer[33] // 1 byte
request.Option = protocol.RequestOption(buffer[34]) // 1 byte + 2 bytes reserved
request.Command = protocol.RequestCommand(buffer[37])
request.Port = v2net.PortFromBytes(buffer[38:40])
switch buffer[40] {
case AddrTypeIPv4:
nBytes, err = io.ReadFull(decryptor, buffer[41:45]) // 4 bytes
bufferLen += 4
if err != nil {
log.Debug("VMess: Failed to read target IPv4 (", nBytes, " bytes): ", err)
return nil, err
}
request.Address = v2net.IPAddress(buffer[41:45])
case AddrTypeIPv6:
nBytes, err = io.ReadFull(decryptor, buffer[41:57]) // 16 bytes
bufferLen += 16
if err != nil {
log.Debug("VMess: Failed to read target IPv6 (", nBytes, " bytes): ", nBytes, err)
return nil, err
}
request.Address = v2net.IPAddress(buffer[41:57])
case AddrTypeDomain:
nBytes, err = io.ReadFull(decryptor, buffer[41:42])
if err != nil {
log.Debug("VMess: Failed to read target domain (", nBytes, " bytes): ", nBytes, err)
return nil, err
}
domainLength := int(buffer[41])
if domainLength == 0 {
return nil, transport.ErrCorruptedPacket
}
nBytes, err = io.ReadFull(decryptor, buffer[42:42+domainLength])
if err != nil {
log.Debug("VMess: Failed to read target domain (", nBytes, " bytes): ", nBytes, err)
return nil, err
}
bufferLen += 1 + domainLength
request.Address = v2net.DomainAddress(string(buffer[42 : 42+domainLength]))
}
nBytes, err = io.ReadFull(decryptor, buffer[bufferLen:bufferLen+4])
if err != nil {
log.Debug("VMess: Failed to read checksum (", nBytes, " bytes): ", nBytes, err)
return nil, err
}
fnv1a := fnv.New32a()
fnv1a.Write(buffer[:bufferLen])
actualHash := fnv1a.Sum32()
expectedHash := serial.BytesToUint32(buffer[bufferLen : bufferLen+4])
if actualHash != expectedHash {
return nil, transport.ErrCorruptedPacket
}
return request, nil
}
// Open implements AEAD.Open().
func (v *FnvAuthenticator) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
if serial.BytesToUint32(ciphertext[:4]) != Authenticate(ciphertext[4:]) {
return dst, crypto.ErrAuthenticationFailed
}
return append(dst, ciphertext[4:]...), nil
}
func (v *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.RequestHeader, error) {
buffer := make([]byte, 512)
_, err := io.ReadFull(reader, buffer[:protocol.IDBytesLen])
if err != nil {
log.Info("VMess|Server: Failed to read request header: ", err)
return nil, io.EOF
}
user, timestamp, valid := v.userValidator.Get(buffer[:protocol.IDBytesLen])
if !valid {
return nil, errors.New("VMess|Server: Invalid user.")
}
timestampHash := md5.New()
timestampHash.Write(hashTimestamp(timestamp))
iv := timestampHash.Sum(nil)
account, err := user.GetTypedAccount()
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to get user account.")
}
aesStream := crypto.NewAesDecryptionStream(account.(*vmess.InternalAccount).ID.CmdKey(), iv)
decryptor := crypto.NewCryptionReader(aesStream, reader)
nBytes, err := io.ReadFull(decryptor, buffer[:41])
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to read request header.")
}
bufferLen := nBytes
request := &protocol.RequestHeader{
User: user,
Version: buffer[0],
}
if request.Version != Version {
return nil, errors.New("VMess|Server: Invalid protocol version ", request.Version)
}
v.requestBodyIV = append([]byte(nil), buffer[1:17]...) // 16 bytes
v.requestBodyKey = append([]byte(nil), buffer[17:33]...) // 16 bytes
v.responseHeader = buffer[33] // 1 byte
request.Option = protocol.RequestOption(buffer[34]) // 1 byte
padingLen := int(buffer[35] >> 4)
request.Security = protocol.NormSecurity(protocol.Security(buffer[35] & 0x0F))
// 1 bytes reserved
request.Command = protocol.RequestCommand(buffer[37])
request.Port = v2net.PortFromBytes(buffer[38:40])
switch buffer[40] {
case AddrTypeIPv4:
_, err = io.ReadFull(decryptor, buffer[41:45]) // 4 bytes
bufferLen += 4
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to read IPv4.")
}
request.Address = v2net.IPAddress(buffer[41:45])
case AddrTypeIPv6:
_, err = io.ReadFull(decryptor, buffer[41:57]) // 16 bytes
bufferLen += 16
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to read IPv6 address.")
}
request.Address = v2net.IPAddress(buffer[41:57])
case AddrTypeDomain:
_, err = io.ReadFull(decryptor, buffer[41:42])
if err != nil {
return nil, errors.Base(err).Message("VMess:Server: Failed to read domain.")
}
domainLength := int(buffer[41])
if domainLength == 0 {
return nil, errors.New("VMess|Server: Zero length domain.")
}
_, err = io.ReadFull(decryptor, buffer[42:42+domainLength])
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to read domain.")
}
bufferLen += 1 + domainLength
request.Address = v2net.DomainAddress(string(buffer[42 : 42+domainLength]))
}
if padingLen > 0 {
_, err = io.ReadFull(decryptor, buffer[bufferLen:bufferLen+padingLen])
if err != nil {
return nil, errors.New("VMess|Server: Failed to read padding.")
}
bufferLen += padingLen
}
_, err = io.ReadFull(decryptor, buffer[bufferLen:bufferLen+4])
if err != nil {
return nil, errors.Base(err).Message("VMess|Server: Failed to read checksum.")
}
fnv1a := fnv.New32a()
fnv1a.Write(buffer[:bufferLen])
actualHash := fnv1a.Sum32()
expectedHash := serial.BytesToUint32(buffer[bufferLen : bufferLen+4])
if actualHash != expectedHash {
return nil, errors.New("VMess|Server: Invalid auth.")
}
if request.Address == nil {
return nil, errors.New("VMess|Server: Invalid remote address.")
}
return request, nil
}
func (this *AuthChunkReader) Read() (*alloc.Buffer, error) {
var buffer *alloc.Buffer
if this.last != nil {
buffer = this.last
this.last = nil
} else {
buffer = alloc.NewBufferWithSize(4096).Clear()
}
if this.chunkLength == -1 {
for buffer.Len() < 6 {
_, err := buffer.FillFrom(this.reader)
if err != nil {
buffer.Release()
return nil, io.ErrUnexpectedEOF
}
}
length := serial.BytesToUint16(buffer.Value[:2])
this.chunkLength = int(length) - 4
this.validator = NewValidator(serial.BytesToUint32(buffer.Value[2:6]))
buffer.SliceFrom(6)
if buffer.Len() < this.chunkLength && this.chunkLength <= 2048 {
_, err := buffer.FillFrom(this.reader)
if err != nil {
buffer.Release()
return nil, io.ErrUnexpectedEOF
}
}
} else if buffer.Len() < this.chunkLength {
_, err := buffer.FillFrom(this.reader)
if err != nil {
buffer.Release()
return nil, io.ErrUnexpectedEOF
}
}
if this.chunkLength == 0 {
buffer.Release()
return nil, io.EOF
}
if buffer.Len() < this.chunkLength {
this.validator.Consume(buffer.Value)
this.chunkLength -= buffer.Len()
} else {
this.validator.Consume(buffer.Value[:this.chunkLength])
if !this.validator.Validate() {
buffer.Release()
return nil, transport.ErrCorruptedPacket
}
leftLength := buffer.Len() - this.chunkLength
if leftLength > 0 {
this.last = alloc.NewBufferWithSize(leftLength + 4096).Clear()
this.last.Append(buffer.Value[this.chunkLength:])
buffer.Slice(0, this.chunkLength)
}
this.chunkLength = -1
this.validator = nil
}
return buffer, nil
}
