// NewDecryptionReader creates a new DescriptionReader by given byte Reader and
// AES key.
func NewDecryptionReader(reader io.Reader, key []byte, iv []byte) (*DecryptionReader, error) {
decryptionReader := new(DecryptionReader)
aesCipher, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
aesBlockMode := cipher.NewCBCDecrypter(aesCipher, iv)
decryptionReader.reader = v2io.NewCryptionReader(aesBlockMode, reader)
decryptionReader.buffer = bytes.NewBuffer(make([]byte, 0, 2*blockSize))
return decryptionReader, nil
}
func (r *VMessRequestReader) Read(reader io.Reader) (*VMessRequest, error) {
buffer := make([]byte, 256)
nBytes, err := reader.Read(buffer[:core.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, ErrorInvalidUser
}
aesCipher, err := aes.NewCipher(userId.CmdKey())
if err != nil {
return nil, err
}
aesStream := cipher.NewCFBDecrypter(aesCipher, v2hash.Int64Hash(timeSec))
decryptor := v2io.NewCryptionReader(aesStream, reader)
if err != nil {
return nil, err
}
nBytes, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
randomLength := buffer[0]
if randomLength <= 0 || randomLength > 32 {
return nil, fmt.Errorf("Unexpected random length %d", randomLength)
}
_, err = decryptor.Read(buffer[:randomLength])
if err != nil {
return nil, err
}
nBytes, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
request := &VMessRequest{
UserId: *userId,
Version: buffer[0],
}
if request.Version != Version {
log.Error("Unknown VMess version %d", request.Version)
return nil, ErrorInvalidVerion
}
// TODO: check number of bytes returned
_, err = decryptor.Read(request.RequestIV[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(request.RequestKey[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(request.ResponseHeader[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
request.Command = buffer[0]
_, err = decryptor.Read(buffer[0:2])
if err != nil {
return nil, err
}
port := binary.BigEndian.Uint16(buffer[0:2])
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
switch buffer[0] {
case addrTypeIPv4:
_, err = decryptor.Read(buffer[1:5])
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[1:5], port)
case addrTypeIPv6:
_, err = decryptor.Read(buffer[1:17])
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[1:17], port)
case addrTypeDomain:
_, err = decryptor.Read(buffer[1:2])
if err != nil {
return nil, err
}
domainLength := buffer[1]
_, err = decryptor.Read(buffer[2 : 2+domainLength])
if err != nil {
return nil, err
}
request.Address = v2net.DomainAddress(string(buffer[2:2+domainLength]), port)
}
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
randomLength = buffer[0]
_, err = decryptor.Read(buffer[:randomLength])
if err != nil {
return nil, err
}
return request, nil
}
func (r *VMessRequestReader) Read(reader io.Reader) (*VMessRequest, error) {
request := new(VMessRequest)
buffer := make([]byte, 256)
nBytes, err := reader.Read(buffer[0:1])
if err != nil {
return nil, err
}
// TODO: verify version number
request.Version = buffer[0]
nBytes, err = reader.Read(buffer[:len(request.UserId)])
if err != nil {
return nil, err
}
userId, valid := r.vUserSet.IsValidUserId(buffer[:nBytes])
if !valid {
return nil, ErrorInvalidUser
}
request.UserId = *userId
aesCipher, err := aes.NewCipher(userId.Hash([]byte("PWD")))
if err != nil {
return nil, err
}
aesStream := cipher.NewCFBDecrypter(aesCipher, emptyIV)
decryptor := v2io.NewCryptionReader(aesStream, reader)
if err != nil {
return nil, err
}
nBytes, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
randomLength := buffer[0]
if randomLength <= 0 || randomLength > 32 {
return nil, fmt.Errorf("Unexpected random length %d", randomLength)
}
_, err = decryptor.Read(buffer[:randomLength])
if err != nil {
return nil, err
}
// TODO: check number of bytes returned
_, err = decryptor.Read(request.RequestIV[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(request.RequestKey[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(request.ResponseHeader[:])
if err != nil {
return nil, err
}
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
request.Command = buffer[0]
_, err = decryptor.Read(buffer[0:2])
if err != nil {
return nil, err
}
port := binary.BigEndian.Uint16(buffer[0:2])
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
switch buffer[0] {
case addrTypeIPv4:
_, err = decryptor.Read(buffer[1:5])
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[1:5], port)
case addrTypeIPv6:
_, err = decryptor.Read(buffer[1:17])
if err != nil {
return nil, err
}
request.Address = v2net.IPAddress(buffer[1:17], port)
case addrTypeDomain:
_, err = decryptor.Read(buffer[1:2])
if err != nil {
return nil, err
}
domainLength := buffer[1]
_, err = decryptor.Read(buffer[2 : 2+domainLength])
if err != nil {
return nil, err
}
request.Address = v2net.DomainAddress(string(buffer[2:2+domainLength]), port)
}
_, err = decryptor.Read(buffer[0:1])
if err != nil {
return nil, err
}
randomLength = buffer[0]
_, err = decryptor.Read(buffer[:randomLength])
if err != nil {
return nil, err
}
return request, nil
}