internal void ProcessData(BinaryReader data)
{
// [ErrorCode 1](ErrorCode == 0: [EncryptionMethod 1][EncryptionMagicValue 4] [RemotePublicKey 256]( EncryptionMethod == AUTH: [PasswordSalt 16]))
ErrorCode = data.ReadByte();
if (ErrorCode == 0)
{
EncryptionMethod = (EEncryptionMethod)data.ReadByte();
EncryptedMagicValue = BBProtocol.ReadByteArray(data);
if (EncryptedMagicValue.Length != 4)
{
IsValid = false;
return;
}
RemotePublicKey = BBProtocol.ReadByteArray(data);
if (RemotePublicKey.Length != 256)
{
IsValid = false;
return;
}
if (EncryptionMethod == EEncryptionMethod.DH_PLUS_AUTH)
{
PasswordSalt = BBProtocol.ReadByteArray(data);
if (PasswordSalt.Length != 16)
{
IsValid = false;
return;
}
}
}
IsValid = true;
}
public BbTcpPacket_StartEncryption(byte byProtolVersion, EEncryptionMethod method, byte[] abyLocalPublicKey, byte[] abyLocalIV, byte[] abyRemoteIV)
: base(BBProtocol.OP_STARTENCRYPTION, byProtolVersion)
{
if (abyLocalPublicKey.Length != 256 || abyLocalIV.Length != 16 || abyRemoteIV.Length != 16)
{
throw new ArgumentException("Invalid Encryption data for remote client");
}
Method = method;
LocalPublicKey = abyLocalPublicKey;
LocalIV = abyLocalIV;
RemoteIV = abyRemoteIV;
}
private async Task HandlePacket(BbTcpPacket packet)
{
if (packet is BbTcpPacket_Hello_Ans && m_bRequestedHello)
{
m_bRequestedHello = false;
BbTcpPacket_Hello_Ans hello_ans = (BbTcpPacket_Hello_Ans)packet;
ServerName = hello_ans.Desc;
ServerGUID = hello_ans.ServerGUID;
ServerMinProtocolVersion = hello_ans.MinSupportedVersion;
m_bRequiresPassword = hello_ans.RequiresPassword;
UsedProtocolVersion = (byte)Math.Min(hello_ans.MaxSupportedVersion, BBProtocol.CURRENT_PROTOCOL_VERSION);
if (UsedProtocolVersion < hello_ans.MinSupportedVersion || UsedProtocolVersion < BBProtocol.MIN_PROTOCOL_VERSION)
{
ProtocolIncompatible = true;
Log.w(TAG, "Server supported protocol versions incompatible - " + ServerName);
Disconnect(false, true);
}
SupportsScreenCapture = hello_ans.SupportsScreenCapture;
IsProVersion = hello_ans.IsProVersion;
Log.d(TAG, "Received Hello Answer from " + ServerName + " Protocol Version: " + UsedProtocolVersion + " Needs Password: "******"Got Pong");
}
else if (packet is BbTcpPacket_EncryptionACK crypt)
{
await ContinueEncryptionNegotiation(crypt);
}
else if (packet is BbTcpPacket_Encryption_AuthAns auth)
{
if (m_abyTestedSharedSecret != null)
{
if (auth.ErrorCode == 0)
{
Log.d(TAG, "DH+Auth negotiated encryption key for session is: " + BitConverter.ToString(m_abyTestedSharedSecret));
m_sendStreamCipher.Init(m_abyTestedSharedSecret);
m_recvStreamCipher.Init(m_abyTestedSharedSecret);
m_bAuthentificated = true;
m_abyTestedSharedSecret = null;
m_dhKeyExchange = null;
m_requestedEncryptionMethod = EEncryptionMethod.NONE;
Log.d(TAG, "Password accepted, DH+Auth Encryption negotiation finished, transmissions will now be encrypted with " + m_sendStreamCipher.Algorithm);
Attach();
}
else
{
Log.w(TAG, "Challenge failed - Password rejected. Trying again.");
m_abyTestedSharedSecret = null;
await Authenticate(true);
}
}
else
{
Log.e(TAG, "Unexpected/Unrequested Encryption_AuthAns packet");
Disconnect(false, false);
}
}
else if (packet is BbTcpPacket_Attach_Ans attach_ans && m_bRequestedAttach)
{
m_bRequestedAttach = false;
if (attach_ans.AttachResult == EAttachResult.ACCEPTED)
{
Attached = true;
WasAttached = true;
ConnectedTime.Start();
Connecting = false;
ConnectionChanged?.Invoke(this, new ConnectionEventArgs(ConnectionEventArgs.EState.CONNECTED, SessionID));
Log.d(TAG, "Attached to " + ServerName);
}
else
{
Log.d(TAG, "Cannot Attach to " + ServerName + " Error: " + attach_ans.AttachResult);
Disconnect(false, false);
}
}