func ReadAuthentication(reader io.Reader) (auth Socks5AuthenticationRequest, auth4 Socks4AuthenticationRequest, err error) {
buffer := alloc.NewSmallBuffer()
defer buffer.Release()
nBytes, err := reader.Read(buffer.Value)
if err != nil {
return
}
if nBytes < 2 {
log.Info("Socks expected 2 bytes read, but only %d bytes read", nBytes)
err = errors.NewCorruptedPacketError()
return
}
if buffer.Value[0] == socks4Version {
auth4.Version = buffer.Value[0]
auth4.Command = buffer.Value[1]
auth4.Port = binary.BigEndian.Uint16(buffer.Value[2:4])
copy(auth4.IP[:], buffer.Value[4:8])
err = NewSocksVersion4Error()
return
}
auth.version = buffer.Value[0]
if auth.version != socksVersion {
err = errors.NewProtocolVersionError(int(auth.version))
return
}
auth.nMethods = buffer.Value[1]
if auth.nMethods <= 0 {
log.Info("Zero length of authentication methods")
err = errors.NewCorruptedPacketError()
return
}
if nBytes-2 != int(auth.nMethods) {
log.Info("Unmatching number of auth methods, expecting %d, but got %d", auth.nMethods, nBytes)
err = errors.NewCorruptedPacketError()
return
}
copy(auth.authMethods[:], buffer.Value[2:nBytes])
return
}
// Read reads a VMessRequest from a byte stream.
func (r *VMessRequestReader) Read(reader io.Reader) (*VMessRequest, error) {
buffer := make([]byte, 256)
nBytes, err := reader.Read(buffer[:user.IDBytesLen])
if err != nil {
return nil, err
}
log.Debug("Read user hash: %v", buffer[:nBytes])
userId, timeSec, valid := r.vUserSet.GetUser(buffer[:nBytes])
if !valid {
return nil, errors.NewAuthenticationError(buffer[:nBytes])
}
aesCipher, err := aes.NewCipher(userId.CmdKey())
if err != nil {
return nil, err
}
aesStream := cipher.NewCFBDecrypter(aesCipher, user.Int64Hash(timeSec))
decryptor := v2io.NewCryptionReader(aesStream, reader)
if err != nil {
return nil, err
}
nBytes, err = decryptor.Read(buffer[:41])
if err != nil {
return nil, err
}
bufferLen := nBytes
request := &VMessRequest{
UserId: *userId,
Version: buffer[0],
}
if request.Version != Version {
return nil, errors.NewProtocolVersionError(int(request.Version))
}
copy(request.RequestIV[:], buffer[1:17]) // 16 bytes
copy(request.RequestKey[:], buffer[17:33]) // 16 bytes
copy(request.ResponseHeader[:], buffer[33:37]) // 4 bytes
request.Command = buffer[37]
port := binary.BigEndian.Uint16(buffer[38:40])
switch buffer[40] {
case addrTypeIPv4:
_, err = decryptor.Read(buffer[41:45]) // 4 bytes
bufferLen += 4
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[41:45], port)
case addrTypeIPv6:
_, err = decryptor.Read(buffer[41:57]) // 16 bytes
bufferLen += 16
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[41:57], port)
case addrTypeDomain:
_, err = decryptor.Read(buffer[41:42])
if err != nil {
return nil, err
}
domainLength := int(buffer[41])
_, err = decryptor.Read(buffer[42 : 42+domainLength])
if err != nil {
return nil, err
}
bufferLen += 1 + domainLength
request.Address = v2net.DomainAddress(string(buffer[42:42+domainLength]), port)
}
_, err = decryptor.Read(buffer[bufferLen : bufferLen+4])
if err != nil {
return nil, err
}
fnv1a := fnv.New32a()
fnv1a.Write(buffer[:bufferLen])
actualHash := fnv1a.Sum32()
expectedHash := binary.BigEndian.Uint32(buffer[bufferLen : bufferLen+4])
if actualHash != expectedHash {
return nil, errors.NewCorruptedPacketError()
}
return request, nil
}