public OutgoingPushMessage encrypt(AxolotlAddress destination, byte[] unpaddedMessage, bool legacy)
{
SessionCipher sessionCipher = new SessionCipher(axolotlStore, destination);
PushTransportDetails transportDetails = new PushTransportDetails(sessionCipher.getSessionVersion());
CiphertextMessage message = sessionCipher.encrypt(transportDetails.getPaddedMessageBody(unpaddedMessage));
uint remoteRegistrationId = sessionCipher.getRemoteRegistrationId();
String body = Base64.encodeBytes(message.serialize());
uint type;
switch (message.getType())
{
case CiphertextMessage.PREKEY_TYPE: type = (uint)Envelope.Types.Type.PREKEY_BUNDLE; break; // todo check
case CiphertextMessage.WHISPER_TYPE: type = (uint)Envelope.Types.Type.CIPHERTEXT; break; // todo check
default: throw new Exception("Bad type: " + message.getType());
}
return new OutgoingPushMessage(type, destination.DeviceId, remoteRegistrationId, legacy ? body : null, legacy ? null : body);
}
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);
}