private void ProcessPortforwardingRequest(ISSHConnectionEventReceiver receiver, SSH1Packet packet)
{
SSH1DataReader reader = new SSH1DataReader(packet.Data);
int server_channel = reader.ReadInt32();
string host = Encoding.ASCII.GetString(reader.ReadString());
int port = reader.ReadInt32();
SSH1DataWriter writer = new SSH1DataWriter();
PortForwardingCheckResult result = receiver.CheckPortForwardingRequest(host, port, "", 0);
if (result.allowed)
{
int local_id = this.RegisterChannelEventReceiver(null, result.channel)._localID;
_eventReceiver.EstablishPortforwarding(result.channel, new SSH1Channel(this, ChannelType.ForwardedRemoteToLocal, local_id, server_channel));
writer.Write(server_channel);
writer.Write(local_id);
SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_MSG_CHANNEL_OPEN_CONFIRMATION, writer.ToByteArray());
p.WriteTo(_stream, _tCipher);
}
else
{
writer.Write(server_channel);
SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_MSG_CHANNEL_OPEN_FAILURE, writer.ToByteArray());
p.WriteTo(_stream, _tCipher);
}
}
private void ExecShell()
{
//System.out.println("EXEC SHELL");
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_EXEC_SHELL);
SSH1Packet.WriteTo(_stream, _tCipher);
}
private void SendPlainPassword()
{
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write(_param.Password);
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_AUTH_PASSWORD, writer.ToByteArray());
SSH1Packet.WriteTo(_stream, _tCipher);
}
private void SendUserName(string username)
{
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write(username);
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_USER, writer.ToByteArray());
SSH1Packet.WriteTo(_stream, _tCipher);
}
//RSA authentication
private void DoRSAChallengeResponse()
{
//read key
SSH1UserAuthKey key = new SSH1UserAuthKey(_param.IdentityFile, _param.Password);
SSH1DataWriter w = new SSH1DataWriter();
w.Write(key.PublicModulus);
SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_AUTH_RSA, w.ToByteArray());
p.WriteTo(_stream, _tCipher);
p = ReceivePacket();
if (p.Type == PacketType.SSH_SMSG_FAILURE)
{
throw new SSHException(Strings.GetString("ServerRefusedRSA"));
}
else if (p.Type != PacketType.SSH_SMSG_AUTH_RSA_CHALLENGE)
{
throw new SSHException(String.Format(Strings.GetString("UnexpectedResponse"), p.Type));
}
//creating challenge
SSH1DataReader r = new SSH1DataReader(p.Data);
BigInteger challenge = key.decryptChallenge(r.ReadMPInt());
byte[] rawchallenge = RSAUtil.StripPKCS1Pad(challenge, 2).getBytes();
//building response
MemoryStream bos = new MemoryStream();
bos.Write(rawchallenge, 0, rawchallenge.Length); //!!mindtermでは頭が０かどうかで変なハンドリングがあった
bos.Write(_sessionID, 0, _sessionID.Length);
byte[] response = new MD5CryptoServiceProvider().ComputeHash(bos.ToArray());
w = new SSH1DataWriter();
w.Write(response);
p = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_AUTH_RSA_RESPONSE, w.ToByteArray());
p.WriteTo(_stream, _tCipher);
}
private void SendRequestPTY()
{
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write(_param.TerminalName);
writer.Write(_param.TerminalHeight);
writer.Write(_param.TerminalWidth);
writer.Write(_param.TerminalPixelWidth);
writer.Write(_param.TerminalPixelHeight);
writer.Write(new byte[1]); //TTY_OP_END
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_REQUEST_PTY, writer.ToByteArray());
SSH1Packet.WriteTo(_stream, _tCipher);
}
public override void Disconnect(string msg)
{
if (_closed)
{
return;
}
SSH1DataWriter w = new SSH1DataWriter();
w.Write(msg);
SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_MSG_DISCONNECT, w.ToByteArray());
p.WriteTo(_stream, _tCipher);
_stream.Flush();
_closed = true;
_stream.Close();
}
public override void ListenForwardedPort(string allowed_host, int bind_port)
{
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write(bind_port);
writer.Write(allowed_host);
writer.Write(0);
SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_PORT_FORWARD_REQUEST, writer.ToByteArray());
p.WriteTo(_stream, _tCipher);
if (_shellID == -1)
{
ExecShell();
_shellID = RegisterChannelEventReceiver(null, new SSH1DummyReceiver())._localID;
}
}
public override SSHChannel ForwardPort(ISSHChannelEventReceiver receiver, string remote_host, int remote_port, string originator_host, int originator_port)
{
if (_shellID == -1)
{
ExecShell();
_shellID = RegisterChannelEventReceiver(null, new SSH1DummyReceiver())._localID;
}
int local_id = this.RegisterChannelEventReceiver(null, receiver)._localID;
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write(local_id); //channel id is fixed to 0
writer.Write(remote_host);
writer.Write(remote_port);
//originator is specified only if SSH_PROTOFLAG_HOST_IN_FWD_OPEN is specified
//writer.Write(originator_host);
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_MSG_PORT_OPEN, writer.ToByteArray());
SSH1Packet.WriteTo(_stream, _tCipher);
return(new SSH1Channel(this, ChannelType.ForwardedLocalToRemote, local_id));
}
private void SendSessionKey(byte[] session_key)
{
try
{
//step1 XOR with session_id
byte[] working_data = new byte[session_key.Length];
byte[] session_id = CalcSessionID();
Array.Copy(session_key, 0, working_data, 0, session_key.Length);
for (int i = 0; i < session_id.Length; i++)
{
working_data[i] ^= session_id[i];
}
//step2 decrypts with RSA
RSAPublicKey first_encryption;
RSAPublicKey second_encryption;
SSHServerInfo si = _cInfo._serverinfo;
int first_key_bytelen, second_key_bytelen;
if (si.server_key_bits < si.host_key_bits)
{
first_encryption = new RSAPublicKey(si.server_key_public_exponent, si.server_key_public_modulus);
second_encryption = new RSAPublicKey(si.host_key_public_exponent, si.host_key_public_modulus);
first_key_bytelen = (si.server_key_bits + 7) / 8;
second_key_bytelen = (si.host_key_bits + 7) / 8;
}
else
{
first_encryption = new RSAPublicKey(si.host_key_public_exponent, si.host_key_public_modulus);
second_encryption = new RSAPublicKey(si.server_key_public_exponent, si.server_key_public_modulus);
first_key_bytelen = (si.host_key_bits + 7) / 8;
second_key_bytelen = (si.server_key_bits + 7) / 8;
}
BigInteger first_result = RSAUtil.PKCS1PadType2(new BigInteger(working_data), first_key_bytelen, _param.Random).modPow(first_encryption.Exponent, first_encryption.Modulus);
BigInteger second_result = RSAUtil.PKCS1PadType2(first_result, second_key_bytelen, _param.Random).modPow(second_encryption.Exponent, second_encryption.Modulus);
//output
SSH1DataWriter writer = new SSH1DataWriter();
writer.Write((byte)_cInfo._algorithmForTransmittion);
writer.Write(si.anti_spoofing_cookie);
writer.Write(second_result);
writer.Write(0); //protocol flags
//send
SSH1Packet SSH1Packet = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_SESSION_KEY, writer.ToByteArray());
SSH1Packet.WriteTo(_stream);
_sessionID = session_id;
}
catch (Exception e)
{
if (e is IOException)
{
throw (IOException)e;
}
else
{
string t = e.StackTrace;
throw new SSHException(e.Message); //IOException以外はみなSSHExceptionにしてしまう
}
}
}
internal void Transmit(SSH1Packet p)
{
lock (this) {
p.WriteTo(_stream, _tCipher);
}
}
internal void Transmit(SSH1Packet p)
{
lock(this) {
p.WriteTo(_stream, _tCipher);
}
}