public OutgoingPushMessage Encrypt(SignalProtocolAddress destination, UnidentifiedAccess unidentifiedAccess, byte[] unpaddedMessage)
{
if (unidentifiedAccess != null)
{
SealedSessionCipher sessionCipher = new SealedSessionCipher(SignalProtocolStore, new SignalProtocolAddress(LocalAddress.E164number, 1));
PushTransportDetails transportDetails = new PushTransportDetails((uint)sessionCipher.GetSessionVersion(destination));
byte[] ciphertext = sessionCipher.Encrypt(destination, unidentifiedAccess.UnidentifiedCertificate, transportDetails.getPaddedMessageBody(unpaddedMessage));
String body = Base64.EncodeBytes(ciphertext);
uint remoteRegistrationId = (uint)sessionCipher.GetRemoteRegistrationId(destination);
return(new OutgoingPushMessage((uint)Envelope.Types.Type.UnidentifiedSender, destination.DeviceId, remoteRegistrationId, body));
}
else
{
SessionCipher sessionCipher = new SessionCipher(SignalProtocolStore, destination);
PushTransportDetails transportDetails = new PushTransportDetails(sessionCipher.getSessionVersion());
CiphertextMessage message = sessionCipher.encrypt(transportDetails.getPaddedMessageBody(unpaddedMessage));
uint remoteRegistrationId = sessionCipher.getRemoteRegistrationId();
string body = Base64.EncodeBytes(message.serialize());
var type = (message.getType()) switch
{
CiphertextMessage.PREKEY_TYPE => (uint)Envelope.Types.Type.PrekeyBundle,
CiphertextMessage.WHISPER_TYPE => (uint)Envelope.Types.Type.Ciphertext,
_ => throw new Exception("Bad type: " + message.getType()),
};
return(new OutgoingPushMessage(type, destination.DeviceId, remoteRegistrationId, body));
}
}
public void TestKeyDerivation()
{
byte[] key = new byte[32];
Arrays.fill(key, 0x02);
byte[] result = UnidentifiedAccess.DeriveAccessKeyFrom(key);
CollectionAssert.AreEqual(EXPECTED_RESULT, result);
}
public bool VerifyUnidentifiedAccess(byte[] theirUnidentifiedAccessVerifier)
{
if (theirUnidentifiedAccessVerifier == null || theirUnidentifiedAccessVerifier.Length == 0)
{
return(false);
}
byte[] unidentifiedAccessKey = UnidentifiedAccess.DeriveAccessKeyFrom(Key);
throw new NotImplementedException();
//TODO
/*
* Mac mac = Mac.getInstance("HmacSHA256");
* mac.init(new SecretKeySpec(unidentifiedAccessKey, "HmacSHA256"));
*
* byte[] ourUnidentifiedAccessVerifier = mac.doFinal(new byte[32]);
*
* return MessageDigest.isEqual(theirUnidentifiedAccessVerifier, ourUnidentifiedAccessVerifier);
*/
}
public bool VerifyUnidentifiedAccess(byte[] theirUnidentifiedAccessVerifier)
{
try
{
if (theirUnidentifiedAccessVerifier == null || theirUnidentifiedAccessVerifier.Length == 0)
{
return(false);
}
byte[] unidentifiedAccessKey = UnidentifiedAccess.DeriveAccessKeyFrom(key);
HMAC mac = new HMACSHA256(unidentifiedAccessKey);
byte[] ourUnidentifiedAccessVerifier = mac.ComputeHash(new byte[32]);
return(Enumerable.SequenceEqual(theirUnidentifiedAccessVerifier, ourUnidentifiedAccessVerifier));
}
catch (InvalidKeyException ex)
{
throw new ArgumentException(null, ex);
}
}
