private void OnGetFullResponse(SocksContext context)
{
List <byte> receivedData = context.ReceivedData;
if (receivedData[0] != 5)
{
OnException("invalid protocol version");
return;
}
byte b = receivedData[1];
if (b == 0)
{
OnCompleted(new ProxyEventArgs(context.Socket));
return;
}
string empty = string.Empty;
switch (b)
{
case 2:
empty = "connection not allowed by ruleset";
break;
case 3:
empty = "network unreachable";
break;
case 4:
empty = "host unreachable";
break;
case 5:
empty = "connection refused by destination host";
break;
case 6:
empty = "TTL expired";
break;
case 7:
empty = "command not supported / protocol error";
break;
case 8:
empty = "address type not supported";
break;
default:
empty = "general failure";
break;
}
OnException(empty);
}
protected override void ProcessSend(SocketAsyncEventArgs e)
{
if (ValidateAsyncResult(e))
{
SocksContext socksContext = e.UserToken as SocksContext;
if (socksContext.State == SocksState.NotAuthenticated)
{
e.SetBuffer(0, 2);
StartReceive(socksContext.Socket, e);
}
else if (socksContext.State == SocksState.Authenticating)
{
e.SetBuffer(0, 2);
StartReceive(socksContext.Socket, e);
}
else
{
e.SetBuffer(0, e.Buffer.Length);
StartReceive(socksContext.Socket, e);
}
}
}
private void OnGetFullResponse(SocksContext context)
{
var response = context.ReceivedData;
if (response[0] != 0x05)
{
OnException("invalid protocol version");
return;
}
var status = response[1];
if (status == 0x00)
{
OnCompleted(new ProxyEventArgs(context.Socket));
return;
}
//0x01 = general failure
//0x02 = connection not allowed by ruleset
//0x03 = network unreachable
//0x04 = host unreachable
//0x05 = connection refused by destination host
//0x06 = TTL expired
//0x07 = command not supported / protocol error
//0x08 = address type not supported
string message = string.Empty;
switch (status)
{
case (0x02):
message = "connection not allowed by ruleset";
break;
case (0x03):
message = "network unreachable";
break;
case (0x04):
message = "host unreachable";
break;
case (0x05):
message = "connection refused by destination host";
break;
case (0x06):
message = "TTL expired";
break;
case (0x07):
message = "command not supported / protocol error";
break;
case (0x08):
message = "address type not supported";
break;
default:
message = "general failure";
break;
}
OnException(message);
}
private void SendHandshake(SocketAsyncEventArgs e)
{
SocksContext socksContext = e.UserToken as SocksContext;
EndPoint targetEndPoint = socksContext.TargetEndPoint;
int num = 0;
byte[] array;
int num2;
if (targetEndPoint is IPEndPoint)
{
IPEndPoint iPEndPoint = targetEndPoint as IPEndPoint;
num = iPEndPoint.Port;
if (iPEndPoint.AddressFamily == AddressFamily.InterNetwork)
{
array = new byte[10]
{
0,
0,
0,
1,
0,
0,
0,
0,
0,
0
};
Buffer.BlockCopy(iPEndPoint.Address.GetAddressBytes(), 0, array, 4, 4);
}
else
{
if (iPEndPoint.AddressFamily != AddressFamily.InterNetworkV6)
{
OnException("unknown address family");
return;
}
array = new byte[22];
array[3] = 4;
Buffer.BlockCopy(iPEndPoint.Address.GetAddressBytes(), 0, array, 4, 16);
}
num2 = array.Length;
}
else
{
DnsEndPoint dnsEndPoint = targetEndPoint as DnsEndPoint;
num = dnsEndPoint.Port;
array = new byte[7 + ProxyConnectorBase.ASCIIEncoding.GetMaxByteCount(dnsEndPoint.Host.Length)];
array[3] = 3;
num2 = 5;
num2 += ProxyConnectorBase.ASCIIEncoding.GetBytes(dnsEndPoint.Host, 0, dnsEndPoint.Host.Length, array, num2);
num2 += 2;
}
array[0] = 5;
array[1] = 1;
array[2] = 0;
array[num2 - 2] = (byte)(num / 256);
array[num2 - 1] = (byte)(num % 256);
e.SetBuffer(array, 0, num2);
socksContext.ReceivedData = new List <byte>(num2 + 5);
socksContext.ExpectedLength = 5;
StartSend(socksContext.Socket, e);
}
protected override void ProcessReceive(SocketAsyncEventArgs e)
{
if (!ValidateAsyncResult(e))
{
return;
}
SocksContext socksContext = (SocksContext)e.UserToken;
if (socksContext.State == SocksState.NotAuthenticated)
{
if (ProcessAuthenticationResponse(socksContext.Socket, e))
{
switch (e.Buffer[1])
{
case 0:
socksContext.State = SocksState.Authenticated;
SendHandshake(e);
break;
case 2:
socksContext.State = SocksState.Authenticating;
AutheticateWithUserNamePassword(e);
break;
case byte.MaxValue:
OnException("no acceptable methods were offered");
break;
default:
OnException("protocol error");
break;
}
}
return;
}
if (socksContext.State == SocksState.Authenticating)
{
if (ProcessAuthenticationResponse(socksContext.Socket, e))
{
if (e.Buffer[1] == 0)
{
socksContext.State = SocksState.Authenticated;
SendHandshake(e);
}
else
{
OnException("authentication failure");
}
}
return;
}
byte[] array = new byte[e.BytesTransferred];
Buffer.BlockCopy(e.Buffer, e.Offset, array, 0, e.BytesTransferred);
socksContext.ReceivedData.AddRange(array);
if (socksContext.ExpectedLength > socksContext.ReceivedData.Count)
{
StartReceive(socksContext.Socket, e);
}
else if (socksContext.State != SocksState.FoundLength)
{
int num;
switch (socksContext.ReceivedData[3])
{
case 1:
num = 10;
break;
case 3:
num = 7 + socksContext.ReceivedData[4];
break;
default:
num = 22;
break;
}
if (socksContext.ReceivedData.Count < num)
{
socksContext.ExpectedLength = num;
StartReceive(socksContext.Socket, e);
}
else if (socksContext.ReceivedData.Count > num)
{
OnException("response length exceeded");
}
else
{
OnGetFullResponse(socksContext);
}
}
else if (socksContext.ReceivedData.Count > socksContext.ExpectedLength)
{
OnException("response length exceeded");
}
else
{
OnGetFullResponse(socksContext);
}
}
private void OnGetFullResponse(SocksContext context)
{
var response = context.ReceivedData;
if (response[0] != 0x05)
{
OnException("invalid protocol version");
return;
}
var status = response[1];
if (status == 0x00)
{
OnCompleted(new ProxyEventArgs(context.Socket));
return;
}
//0x01 = general failure
//0x02 = connection not allowed by ruleset
//0x03 = network unreachable
//0x04 = host unreachable
//0x05 = connection refused by destination host
//0x06 = TTL expired
//0x07 = command not supported / protocol error
//0x08 = address type not supported
string message = string.Empty;
switch (status)
{
case (0x02):
message = "connection not allowed by ruleset";
break;
case (0x03):
message = "network unreachable";
break;
case (0x04):
message = "host unreachable";
break;
case (0x05):
message = "connection refused by destination host";
break;
case (0x06):
message = "TTL expired";
break;
case (0x07):
message = "command not supported / protocol error";
break;
case (0x08):
message = "address type not supported";
break;
default:
message = "general failure";
break;
}
OnException(message);
}
