private void ReceiveServerKeys() { DataFragment packet = ReceivePacket(); SSH1DataReader reader = new SSH1DataReader(packet); PacketType pt = reader.ReadPacketType(); if (pt != PacketType.SSH_SMSG_PUBLIC_KEY) throw new SSHException("unexpected SSH SSH1Packet type " + pt, reader.ReadAll()); _cInfo._serverinfo = new SSHServerInfo(reader); _cInfo._hostkey = new RSAPublicKey(_cInfo._serverinfo.host_key_public_exponent, _cInfo._serverinfo.host_key_public_modulus); //read protocol support parameters int protocol_flags = reader.ReadInt32(); int supported_ciphers_mask = reader.ReadInt32(); _cInfo.SetSupportedCipherAlgorithms(supported_ciphers_mask); int supported_authentications_mask = reader.ReadInt32(); //Debug.WriteLine(String.Format("ServerOptions {0} {1} {2}", protocol_flags, supported_ciphers_mask, supported_authentications_mask)); if (reader.Rest > 0) throw new SSHException("data length mismatch", reader.ReadAll()); bool found = false; foreach (CipherAlgorithm a in _param.PreferableCipherAlgorithms) { if (a != CipherAlgorithm.Blowfish && a != CipherAlgorithm.TripleDES) continue; else if (a == CipherAlgorithm.Blowfish && (supported_ciphers_mask & (1 << (int)CipherAlgorithm.Blowfish)) == 0) continue; else if (a == CipherAlgorithm.TripleDES && (supported_ciphers_mask & (1 << (int)CipherAlgorithm.TripleDES)) == 0) continue; _cInfo._algorithmForReception = _cInfo._algorithmForTransmittion = a; found = true; break; } if (!found) throw new SSHException(String.Format(Strings.GetString("ServerNotSupportedX"), "Blowfish/TripleDES")); if (_param.AuthenticationType == AuthenticationType.Password && (supported_authentications_mask & (1 << (int)AuthenticationType.Password)) == 0) throw new SSHException(String.Format(Strings.GetString("ServerNotSupportedPassword")), reader.ReadAll()); if (_param.AuthenticationType == AuthenticationType.PublicKey && (supported_authentications_mask & (1 << (int)AuthenticationType.PublicKey)) == 0) throw new SSHException(String.Format(Strings.GetString("ServerNotSupportedRSA")), reader.ReadAll()); TraceReceptionEvent(pt, "received server key"); }
private DataFragment ReceivePacket() { while (true) { DataFragment data = _packetReceiver.WaitResponse(); PacketType pt = (PacketType)data.ByteAt(0); //shortcut if (pt == PacketType.SSH_MSG_IGNORE) { SSH1DataReader r = new SSH1DataReader(data); r.ReadPacketType(); if (_eventReceiver != null) _eventReceiver.OnIgnoreMessage(r.ReadString()); } else if (pt == PacketType.SSH_MSG_DEBUG) { SSH1DataReader r = new SSH1DataReader(data); r.ReadPacketType(); if (_eventReceiver != null) _eventReceiver.OnDebugMessage(false, r.ReadString()); } else return data; } }
//RSA authentication private void DoRSAChallengeResponse() { //read key SSH1UserAuthKey key = new SSH1UserAuthKey(_param.IdentityFile, _param.Password); SSH1DataWriter w = new SSH1DataWriter(); w.WriteBigInteger(key.PublicModulus); SSH1Packet p = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_AUTH_RSA, w.ToByteArray()); p.WriteTo(_stream, _tCipher); TraceTransmissionEvent(PacketType.SSH_CMSG_AUTH_RSA, "RSA challenge-reponse"); DataFragment response = ReceivePacket(); SSH1DataReader reader = new SSH1DataReader(response); PacketType pt = reader.ReadPacketType(); if (pt == PacketType.SSH_SMSG_FAILURE) throw new SSHException(Strings.GetString("ServerRefusedRSA")); else if (pt != PacketType.SSH_SMSG_AUTH_RSA_CHALLENGE) throw new SSHException(String.Format(Strings.GetString("UnexpectedResponse"), pt)); TraceReceptionEvent(PacketType.SSH_SMSG_AUTH_RSA_CHALLENGE, "received challenge"); //creating challenge BigInteger challenge = key.decryptChallenge(reader.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[] reply = new MD5CryptoServiceProvider().ComputeHash(bos.ToArray()); w = new SSH1DataWriter(); w.Write(reply); p = SSH1Packet.FromPlainPayload(PacketType.SSH_CMSG_AUTH_RSA_RESPONSE, w.ToByteArray()); p.WriteTo(_stream, _tCipher); TraceReceptionEvent(PacketType.SSH_CMSG_AUTH_RSA_RESPONSE, "received response"); }
private bool ReceiveAuthenticationResult() { DataFragment packet = ReceivePacket(); SSH1DataReader r = new SSH1DataReader(packet); PacketType type = r.ReadPacketType(); TraceReceptionEvent(type, "user authentication response"); if (type == PacketType.SSH_MSG_DEBUG) { //Debug.WriteLine("receivedd debug message:"+Encoding.ASCII.GetString(r.ReadString())); return ReceiveAuthenticationResult(); } else if (type == PacketType.SSH_SMSG_SUCCESS) return true; else if (type == PacketType.SSH_SMSG_FAILURE) return false; else throw new SSHException("unexpected type: " + type); }
internal void AsyncReceivePacket(DataFragment data) { try { int len = 0, channel = 0; SSH1DataReader re = new SSH1DataReader(data); PacketType pt = re.ReadPacketType(); switch (pt) { case PacketType.SSH_SMSG_STDOUT_DATA: len = re.ReadInt32(); _channel_collection.FindChannelEntry(_shellID).Receiver.OnData(re.Image, re.Offset, len); break; case PacketType.SSH_SMSG_STDERR_DATA: { _channel_collection.FindChannelEntry(_shellID).Receiver.OnExtendedData((int)PacketType.SSH_SMSG_STDERR_DATA, re.ReadString()); } break; case PacketType.SSH_MSG_CHANNEL_DATA: channel = re.ReadInt32(); len = re.ReadInt32(); _channel_collection.FindChannelEntry(channel).Receiver.OnData(re.Image, re.Offset, len); break; case PacketType.SSH_MSG_PORT_OPEN: ProcessPortforwardingRequest(_eventReceiver, re); break; case PacketType.SSH_MSG_CHANNEL_CLOSE: { channel = re.ReadInt32(); ISSHChannelEventReceiver r = _channel_collection.FindChannelEntry(channel).Receiver; _channel_collection.UnregisterChannelEventReceiver(channel); r.OnChannelClosed(); } break; case PacketType.SSH_MSG_CHANNEL_CLOSE_CONFIRMATION: channel = re.ReadInt32(); break; case PacketType.SSH_MSG_DISCONNECT: _eventReceiver.OnConnectionClosed(); break; case PacketType.SSH_SMSG_EXITSTATUS: _channel_collection.FindChannelEntry(_shellID).Receiver.OnChannelClosed(); break; case PacketType.SSH_MSG_DEBUG: _eventReceiver.OnDebugMessage(false, re.ReadString()); break; case PacketType.SSH_MSG_IGNORE: _eventReceiver.OnIgnoreMessage(re.ReadString()); break; case PacketType.SSH_MSG_CHANNEL_OPEN_CONFIRMATION: { int local = re.ReadInt32(); int remote = re.ReadInt32(); _channel_collection.FindChannelEntry(local).Receiver.OnChannelReady(); } break; case PacketType.SSH_SMSG_SUCCESS: if (_executingShell) { ExecShell(); _channel_collection.FindChannelEntry(_shellID).Receiver.OnChannelReady(); _executingShell = false; } break; default: _eventReceiver.OnUnknownMessage((byte)pt, re.ReadAll()); break; } } catch (Exception ex) { _eventReceiver.OnError(ex); } }