public void Test_OmemoKeyExchangeMessage()
{
Random rand = new Random();
byte[] hmac = new byte[16];
rand.NextBytes(hmac);
byte[] sessionKey = new byte[32];
rand.NextBytes(sessionKey);
IdentityKeyPairModel identityKey = KeyHelper.GenerateIdentityKeyPair();
SignedPreKeyModel signedPreKey = KeyHelper.GenerateSignedPreKey(0, identityKey.privKey);
OmemoSessionModel refOmemoSession = new OmemoSessionModel(new Bundle()
{
identityKey = identityKey.pubKey,
preKeys = KeyHelper.GeneratePreKeys(0, 10),
preKeySignature = signedPreKey.signature,
signedPreKey = signedPreKey.preKey.pubKey,
signedPreKeyId = signedPreKey.preKey.keyId
}, 0, KeyHelper.GenerateIdentityKeyPair())
{
ek = KeyHelper.GenerateKeyPair().pubKey
};
OmemoMessage refOmemoMessage = new OmemoMessage(refOmemoSession);
OmemoAuthenticatedMessage refOmemoAuthenticatedMessage = new OmemoAuthenticatedMessage(new byte[16], refOmemoMessage.ToByteArray());
OmemoKeyExchangeMessage refOmemoKeyExchangeMessage = new OmemoKeyExchangeMessage((uint)rand.Next(), (uint)rand.Next(), KeyHelper.GenerateKeyPair().pubKey, KeyHelper.GenerateKeyPair().pubKey, refOmemoAuthenticatedMessage);
byte[] data = refOmemoKeyExchangeMessage.ToByteArray();
Assert.IsTrue(data.Length > 0);
OmemoKeyExchangeMessage omemoKeyExchangeMessage = new OmemoKeyExchangeMessage(data);
Assert.IsTrue(omemoKeyExchangeMessage.Equals(refOmemoKeyExchangeMessage));
}
/// <summary>
/// Encrypts the given <paramref name="keyHmac"/> combination for all given devices and returns the resulting messages.
/// Uses the given <see cref="OmemoSessionModel"/> for encrypting.
/// </summary>
/// <param name="keyHmac">The key HMAC combination, that should be encrypted.</param>
/// <param name="devices">A collection of devices, we should encrypt the message for.</param>
/// <returns>A collection of encrypted messages for each device grouped by their bare JID (List[Tuple[bareJid, List[Tuple[deviceId, IOmemoMessage]]]]).</returns>
public List <Tuple <string, List <Tuple <uint, IOmemoMessage> > > > EncryptKeyHmacForDevices(byte[] keyHmac, List <OmemoDeviceGroup> devices)
{
List <Tuple <string, List <Tuple <uint, IOmemoMessage> > > > msgs = new List <Tuple <string, List <Tuple <uint, IOmemoMessage> > > >();
foreach (OmemoDeviceGroup group in devices)
{
List <Tuple <uint, IOmemoMessage> > groupMsgs = new List <Tuple <uint, IOmemoMessage> >();
foreach (KeyValuePair <uint, OmemoSessionModel> device in group.SESSIONS)
{
try
{
OmemoSessionModel session = device.Value;
OmemoAuthenticatedMessage authMsg = EncryptKeyHmacForDevices(keyHmac, device.Value, session.assData);
// To account for lost and out-of-order messages during the key exchange, OmemoKeyExchange structures are sent until a response by the recipient confirms that the key exchange was successfully completed.
if (session.nS == 0 || session.nR == 0)
{
OmemoKeyExchangeMessage kexMsg = new OmemoKeyExchangeMessage(session.preKeyId, session.signedPreKeyId, OWN_IDENTITY_KEY.pubKey, session.ek, authMsg);
groupMsgs.Add(new Tuple <uint, IOmemoMessage>(device.Key, kexMsg));
}
else
{
groupMsgs.Add(new Tuple <uint, IOmemoMessage>(device.Key, authMsg));
}
}
catch (OmemoException e)
{
Logger.Error("Failed to encrypt message for device " + group.ToString() + " with: " + e.ToString());
}
}
msgs.Add(new Tuple <string, List <Tuple <uint, IOmemoMessage> > >(group.BARE_JID, groupMsgs));
}
return(msgs);
}
