public int EndReceiveFrom(IAsyncResult ar, ref EndPoint ep)
{
int bytesRead = _socket.EndReceiveFrom(ar, ref ep);
if (bytesRead > 0)
{
CallbackState st = (CallbackState)ar.AsyncState;
st.size = bytesRead;
int bytesToSend;
if (!RemoveRemoteUDPRecvBufferHeader(st.buffer, ref bytesRead))
{
return(0); // drop
}
byte[] remoteSendBuffer = new byte[65536];
byte[] obfsBuffer;
lock (_decryptionLock)
{
byte[] decryptBuffer = new byte[65536];
_encryptor.ResetDecrypt();
_encryptor.Decrypt(st.buffer, bytesRead, decryptBuffer, out bytesToSend);
obfsBuffer = _protocol.ClientUdpPostDecrypt(decryptBuffer, bytesToSend, out bytesToSend);
decryptBuffer = ParseUDPHeader(obfsBuffer, ref bytesToSend);
AddRemoteUDPRecvBufferHeader(decryptBuffer, remoteSendBuffer, ref bytesToSend);
}
Array.Copy(remoteSendBuffer, 0, st.buffer, 0, bytesToSend);
return(bytesToSend);
}
else
{
_close = true;
}
return(bytesRead);
}
public int BeginSend(byte[] buffer, int size, SocketFlags flags, AsyncCallback callback, object state)
{
CallbackState st = new CallbackState
{
size = size,
state = state
};
_socket.BeginSend(buffer, 0, size, 0, callback, st);
return(size);
}
public IAsyncResult BeginReceiveFrom(byte[] buffer, int size, SocketFlags flags, ref EndPoint ep, AsyncCallback callback, object state)
{
CallbackState st = new CallbackState
{
buffer = buffer,
size = size,
state = state
};
return(_socket.BeginReceiveFrom(buffer, 0, size, flags, ref ep, callback, st));
}
public int EndReceive(IAsyncResult ar)
{
int bytesRead = _socket.EndReceive(ar);
if (bytesRead > 0)
{
CallbackState st = (CallbackState)ar.AsyncState;
st.size = bytesRead;
return(bytesRead);
}
else
{
_close = true;
}
return(bytesRead);
}
public int EndReceive(IAsyncResult ar, out bool sendback)
{
int bytesRead = _socket.EndReceive(ar);
sendback = false;
if (bytesRead > 0)
{
CallbackState st = (CallbackState)ar.AsyncState;
st.size = bytesRead;
lock (_decryptionLock)
{
int bytesToSend = 0;
byte[] remoteRecvObfsBuffer = _obfs.ClientDecode(st.buffer, bytesRead, out int obfsRecvSize, out sendback);
if (obfsRecvSize > 0)
{
Util.Utils.SetArrayMinSize(ref ReceiveDecryptBuffer, obfsRecvSize);
_encryptor.Decrypt(remoteRecvObfsBuffer, obfsRecvSize, ReceiveDecryptBuffer, out bytesToSend);
st.protocol_size = bytesToSend;
byte[] buffer = _protocol.ClientPostDecrypt(ReceiveDecryptBuffer, bytesToSend, out int outlength);
TcpMSS = _protocol.GetTcpMSS();
if (st.buffer.Length < outlength)
{
Array.Resize(ref st.buffer, outlength);
}
Array.Copy(buffer, 0, st.buffer, 0, outlength);
return(outlength);
}
}
return(0);
}
else
{
_close = true;
}
return(bytesRead);
}
public int BeginSendTo(byte[] buffer, int size, SocketFlags flags, AsyncCallback callback, object state)
{
CallbackState st = new CallbackState
{
buffer = buffer,
size = size,
state = state
};
int bytesToSend;
byte[] bytesToEncrypt = null;
byte[] connetionSendBuffer = new byte[65536];
int bytes_beg = 3;
int length = size - bytes_beg;
bytesToEncrypt = new byte[length];
Array.Copy(buffer, bytes_beg, bytesToEncrypt, 0, length);
lock (_encryptionLock)
{
_encryptor.ResetEncrypt();
_protocol.SetServerInfoIV(_encryptor.getIV());
byte[] obfsBuffer = _protocol.ClientUdpPreEncrypt(bytesToEncrypt, length, out int obfsSendSize);
_encryptor.Encrypt(obfsBuffer, obfsSendSize, connetionSendBuffer, out bytesToSend);
}
if (_proxy)
{
string serverURI = _proxy_server;
int serverPort = _proxy_udp_port;
bool parsed = IPAddress.TryParse(serverURI, out IPAddress ipAddress);
if (!parsed)
{
bytesToEncrypt = new byte[bytes_beg + 1 + 1 + serverURI.Length + 2 + bytesToSend];
Array.Copy(connetionSendBuffer, 0, bytesToEncrypt, bytes_beg + 1 + 1 + serverURI.Length + 2, bytesToSend);
bytesToEncrypt[0] = 0;
bytesToEncrypt[1] = 0;
bytesToEncrypt[2] = 0;
bytesToEncrypt[3] = 3;
bytesToEncrypt[4] = (byte)serverURI.Length;
for (int i = 0; i < serverURI.Length; ++i)
{
bytesToEncrypt[5 + i] = (byte)serverURI[i];
}
bytesToEncrypt[5 + serverURI.Length] = (byte)(serverPort / 0x100);
bytesToEncrypt[5 + serverURI.Length + 1] = (byte)(serverPort % 0x100);
}
else
{
byte[] addBytes = ipAddress.GetAddressBytes();
bytesToEncrypt = new byte[bytes_beg + 1 + addBytes.Length + 2 + bytesToSend];
Array.Copy(connetionSendBuffer, 0, bytesToEncrypt, bytes_beg + 1 + addBytes.Length + 2, bytesToSend);
bytesToEncrypt[0] = 0;
bytesToEncrypt[1] = 0;
bytesToEncrypt[2] = 0;
bytesToEncrypt[3] = ipAddress.AddressFamily == AddressFamily.InterNetworkV6 ? (byte)4 : (byte)1;
for (int i = 0; i < addBytes.Length; ++i)
{
bytesToEncrypt[4 + i] = addBytes[i];
}
bytesToEncrypt[4 + addBytes.Length] = (byte)(serverPort / 0x100);
bytesToEncrypt[4 + addBytes.Length + 1] = (byte)(serverPort % 0x100);
}
bytesToSend = bytesToEncrypt.Length;
Array.Copy(bytesToEncrypt, connetionSendBuffer, bytesToSend);
}
_socket.BeginSendTo(connetionSendBuffer, 0, bytesToSend, flags, _remoteUDPEndPoint, callback, st);
return(bytesToSend);
}
public byte[] GetAsyncResultBuffer(IAsyncResult ar)
{
CallbackState st = (CallbackState)ar.AsyncState;
return(st.buffer);
}
public int GetAsyncResultSize(IAsyncResult ar)
{
CallbackState st = (CallbackState)ar.AsyncState;
return(st.size);
}
public int GetAsyncProtocolSize(IAsyncResult ar)
{
CallbackState st = (CallbackState)ar.AsyncState;
return(st.protocol_size);
}
