private byte[] decrypt(SignalServiceEnvelope envelope, byte[] ciphertext)
{
SignalProtocolAddress sourceAddress = new SignalProtocolAddress(envelope.getSource(), (uint)envelope.getSourceDevice());
SessionCipher sessionCipher = new SessionCipher(signalProtocolStore, sourceAddress);
byte[] paddedMessage;
if (envelope.isPreKeySignalMessage())
{
paddedMessage = sessionCipher.decrypt(new PreKeySignalMessage(ciphertext));
}
else if (envelope.isSignalMessage())
{
paddedMessage = sessionCipher.decrypt(new SignalMessage(ciphertext));
}
else
{
throw new InvalidMessageException("Unknown type: " + envelope.getType() + " from " + envelope.getSource());
}
PushTransportDetails transportDetails = new PushTransportDetails(sessionCipher.getSessionVersion());
return(transportDetails.getStrippedPaddingMessageBody(paddedMessage));
}
private byte[] decrypt(TextSecureEnvelope envelope, byte[] ciphertext)
{
AxolotlAddress sourceAddress = new AxolotlAddress(envelope.getSource(), envelope.getSourceDevice());
SessionCipher sessionCipher = new SessionCipher(axolotlStore, sourceAddress);
byte[] paddedMessage;
if (envelope.isPreKeyWhisperMessage())
{
paddedMessage = sessionCipher.decrypt(new PreKeyWhisperMessage(ciphertext));
}
else if (envelope.isWhisperMessage())
{
paddedMessage = sessionCipher.decrypt(new WhisperMessage(ciphertext));
}
else
{
throw new InvalidMessageException("Unknown type: " + envelope.getType());
}
PushTransportDetails transportDetails = new PushTransportDetails(sessionCipher.getSessionVersion());
return(transportDetails.getStrippedPaddingMessageBody(paddedMessage));
}