private Socks4Request(Socks4Command cmd, int remotePort, IPAddress remoteHostIP, string userID, string remoteHost)
{
this.ProxyType = string.IsNullOrEmpty(remoteHost) ? SocksProxyType.Socks4 : SocksProxyType.Socks4a;
this.Command = cmd;
this.RemotePort = remotePort;
this.RemoteIP = remoteHostIP;
this.UserID = userID;
this.RemoteHost = remoteHost;
}
static bool TryParse(byte[] request, int requestLength, out Socks4Command cmd, out int port, out IPAddress addr, out string user)
{
// +----+-----+----------+----------+----------+-------+--------------+-------+
// |VER | CMD | DST.PORT | DST.ADDR | USERID | NULL | DST.DOMAIN | NULL |
// +----+-----+----------+----------+----------+-------+--------------+-------+
// | 1 | 1 | 2 | 4 | VARIABLE | X'00' | VARIABLE | X'00' |
// +----+-----+----------+----------+----------+-------+--------------+-------+
int n = 0;
cmd = Socks4Command.Connect;
addr = null;
user = null;
port = 0;
if (requestLength < 9 || request[n++] != (byte)4)
{
return(false);
}
cmd = (Socks4Command)request[n++];
if (cmd != Socks4Command.Connect && cmd != Socks4Command.Bind)
{
return(false);
}
port = (request[n++] << 8) | request[n++];
var ip = new byte[4];
Buffer.BlockCopy(request, n, ip, 0, 4);
n += 4;
if (!IsInvalidIPAddress(ip))
{
addr = new IPAddress(ip);
}
var buffer = new byte[256];
int index = 0;
while (n < requestLength && index < buffer.Length && request[n] != 0)
{
buffer[index++] = request[n++];
}
if (n >= requestLength || index >= buffer.Length)
{
return(false);
}
user = Encoding.UTF8.GetString(buffer, 0, index);
n++;
return(addr != null);
}
public Socks4Request(Socks4Command cmd, DnsEndPoint remoteEndPoint, string userID = null)
: this(cmd, remoteEndPoint.Port, new IPAddress(new byte[] { 0, 0, 0, 1 }), userID ?? string.Empty, remoteEndPoint.Host)
{
}
public Socks4Request(Socks4Command cmd, IPEndPoint remoteEndPoint, string userID = null)
: this(cmd, remoteEndPoint.Port, remoteEndPoint.Address, userID ?? string.Empty, string.Empty)
{
}
