/// <summary>
/// Build a new session from a {@link org.whispersystems.libsignal.state.PreKeyBundle} retrieved from
/// a server.
/// </summary>
/// @param preKey A PreKey for the destination recipient, retrieved from a server.
/// @throws InvalidKeyException when the {@link org.whispersystems.libsignal.state.PreKeyBundle} is
/// badly formatted.
/// @throws org.whispersystems.libsignal.UntrustedIdentityException when the sender's
/// {@link IdentityKey} is not
/// trusted.
///
public void Process(PreKeyBundle preKey)
{
lock (SessionCipher.SessionLock)
{
if (!_identityKeyStore.IsTrustedIdentity(_remoteAddress, preKey.GetIdentityKey(), Direction.Sending))
{
throw new UntrustedIdentityException(_remoteAddress.Name, preKey.GetIdentityKey());
}
if (preKey.GetSignedPreKey() != null &&
!Curve.VerifySignature(preKey.GetIdentityKey().GetPublicKey(),
preKey.GetSignedPreKey().Serialize(),
preKey.GetSignedPreKeySignature()))
{
throw new InvalidKeyException("Invalid signature on device key!");
}
if (preKey.GetSignedPreKey() == null)
{
throw new InvalidKeyException("No signed prekey!");
}
SessionRecord sessionRecord = _sessionStore.LoadSession(_remoteAddress);
EcKeyPair ourBaseKey = Curve.GenerateKeyPair();
IEcPublicKey theirSignedPreKey = preKey.GetSignedPreKey();
IEcPublicKey test = preKey.GetPreKey();
May <IEcPublicKey> theirOneTimePreKey = (test == null) ? May <IEcPublicKey> .NoValue : new May <IEcPublicKey>(test);
May <uint> theirOneTimePreKeyId = theirOneTimePreKey.HasValue ? new May <uint>(preKey.GetPreKeyId()) :
May <uint> .NoValue;
AliceSignalProtocolParameters.Builder parameters = AliceSignalProtocolParameters.NewBuilder();
parameters.SetOurBaseKey(ourBaseKey)
.SetOurIdentityKey(_identityKeyStore.GetIdentityKeyPair())
.SetTheirIdentityKey(preKey.GetIdentityKey())
.SetTheirSignedPreKey(theirSignedPreKey)
.SetTheirRatchetKey(theirSignedPreKey)
.SetTheirOneTimePreKey(theirOneTimePreKey);
if (!sessionRecord.IsFresh())
{
sessionRecord.ArchiveCurrentState();
}
RatchetingSession.InitializeSession(sessionRecord.GetSessionState(), parameters.Create());
sessionRecord.GetSessionState().SetUnacknowledgedPreKeyMessage(theirOneTimePreKeyId, preKey.GetSignedPreKeyId(), ourBaseKey.GetPublicKey());
sessionRecord.GetSessionState().SetLocalRegistrationId(_identityKeyStore.GetLocalRegistrationId());
sessionRecord.GetSessionState().SetRemoteRegistrationId(preKey.GetRegistrationId());
sessionRecord.GetSessionState().SetAliceBaseKey(ourBaseKey.GetPublicKey().Serialize());
_identityKeyStore.SaveIdentity(_remoteAddress, preKey.GetIdentityKey());
_sessionStore.StoreSession(_remoteAddress, sessionRecord);
}
}
private void InitializeSessionsV3(SessionState aliceSessionState, SessionState bobSessionState)
{
EcKeyPair aliceIdentityKeyPair = Curve.GenerateKeyPair();
IdentityKeyPair aliceIdentityKey = new IdentityKeyPair(new IdentityKey(aliceIdentityKeyPair.GetPublicKey()),
aliceIdentityKeyPair.GetPrivateKey());
EcKeyPair aliceBaseKey = Curve.GenerateKeyPair();
EcKeyPair aliceEphemeralKey = Curve.GenerateKeyPair();
EcKeyPair alicePreKey = aliceBaseKey;
EcKeyPair bobIdentityKeyPair = Curve.GenerateKeyPair();
IdentityKeyPair bobIdentityKey = new IdentityKeyPair(new IdentityKey(bobIdentityKeyPair.GetPublicKey()),
bobIdentityKeyPair.GetPrivateKey());
EcKeyPair bobBaseKey = Curve.GenerateKeyPair();
EcKeyPair bobEphemeralKey = bobBaseKey;
EcKeyPair bobPreKey = Curve.GenerateKeyPair();
AliceSignalProtocolParameters aliceParameters = AliceSignalProtocolParameters.NewBuilder()
.SetOurBaseKey(aliceBaseKey)
.SetOurIdentityKey(aliceIdentityKey)
.SetTheirOneTimePreKey(May <IEcPublicKey> .NoValue)
.SetTheirRatchetKey(bobEphemeralKey.GetPublicKey())
.SetTheirSignedPreKey(bobBaseKey.GetPublicKey())
.SetTheirIdentityKey(bobIdentityKey.GetPublicKey())
.Create();
BobSignalProtocolParameters bobParameters = BobSignalProtocolParameters.NewBuilder()
.SetOurRatchetKey(bobEphemeralKey)
.SetOurSignedPreKey(bobBaseKey)
.SetOurOneTimePreKey(May <EcKeyPair> .NoValue)
.SetOurIdentityKey(bobIdentityKey)
.SetTheirIdentityKey(aliceIdentityKey.GetPublicKey())
.SetTheirBaseKey(aliceBaseKey.GetPublicKey())
.Create();
RatchetingSession.InitializeSession(aliceSessionState, aliceParameters);
RatchetingSession.InitializeSession(bobSessionState, bobParameters);
}
public void TestRatchetingSessionAsAlice()
{
byte[] bobPublic = { (byte)0x05, (byte)0x2c, (byte)0xb4, (byte)0x97, (byte)0x76,
(byte)0xb8, (byte)0x77, (byte)0x02, (byte)0x05, (byte)0x74,
(byte)0x5a, (byte)0x3a, (byte)0x6e, (byte)0x24, (byte)0xf5,
(byte)0x79, (byte)0xcd, (byte)0xb4, (byte)0xba, (byte)0x7a,
(byte)0x89, (byte)0x04, (byte)0x10, (byte)0x05, (byte)0x92,
(byte)0x8e, (byte)0xbb, (byte)0xad, (byte)0xc9, (byte)0xc0,
(byte)0x5a, (byte)0xd4, (byte)0x58 };
byte[] bobIdentityPublic = { (byte)0x05, (byte)0xf1, (byte)0xf4, (byte)0x38, (byte)0x74,
(byte)0xf6, (byte)0x96, (byte)0x69, (byte)0x56, (byte)0xc2,
(byte)0xdd, (byte)0x47, (byte)0x3f, (byte)0x8f, (byte)0xa1,
(byte)0x5a, (byte)0xde, (byte)0xb7, (byte)0x1d, (byte)0x1c,
(byte)0xb9, (byte)0x91, (byte)0xb2, (byte)0x34, (byte)0x16,
(byte)0x92, (byte)0x32, (byte)0x4c, (byte)0xef, (byte)0xb1,
(byte)0xc5, (byte)0xe6, (byte)0x26 };
byte[] bobSignedPreKeyPublic = { (byte)0x05, (byte)0xac, (byte)0x24, (byte)0x8a, (byte)0x8f,
(byte)0x26, (byte)0x3b, (byte)0xe6, (byte)0x86, (byte)0x35,
(byte)0x76, (byte)0xeb, (byte)0x03, (byte)0x62, (byte)0xe2,
(byte)0x8c, (byte)0x82, (byte)0x8f, (byte)0x01, (byte)0x07,
(byte)0xa3, (byte)0x37, (byte)0x9d, (byte)0x34, (byte)0xba,
(byte)0xb1, (byte)0x58, (byte)0x6b, (byte)0xf8, (byte)0xc7,
(byte)0x70, (byte)0xcd, (byte)0x67 };
byte[] aliceBasePublic = { (byte)0x05, (byte)0x47, (byte)0x2d, (byte)0x1f, (byte)0xb1,
(byte)0xa9, (byte)0x86, (byte)0x2c, (byte)0x3a, (byte)0xf6,
(byte)0xbe, (byte)0xac, (byte)0xa8, (byte)0x92, (byte)0x02,
(byte)0x77, (byte)0xe2, (byte)0xb2, (byte)0x6f, (byte)0x4a,
(byte)0x79, (byte)0x21, (byte)0x3e, (byte)0xc7, (byte)0xc9,
(byte)0x06, (byte)0xae, (byte)0xb3, (byte)0x5e, (byte)0x03,
(byte)0xcf, (byte)0x89, (byte)0x50 };
byte[] aliceBasePrivate = { (byte)0x11, (byte)0xae, (byte)0x7c, (byte)0x64, (byte)0xd1,
(byte)0xe6, (byte)0x1c, (byte)0xd5, (byte)0x96, (byte)0xb7,
(byte)0x6a, (byte)0x0d, (byte)0xb5, (byte)0x01, (byte)0x26,
(byte)0x73, (byte)0x39, (byte)0x1c, (byte)0xae, (byte)0x66,
(byte)0xed, (byte)0xbf, (byte)0xcf, (byte)0x07, (byte)0x3b,
(byte)0x4d, (byte)0xa8, (byte)0x05, (byte)0x16, (byte)0xa4,
(byte)0x74, (byte)0x49 };
byte[] aliceEphemeralPublic = { (byte)0x05, (byte)0x6c, (byte)0x3e, (byte)0x0d, (byte)0x1f,
(byte)0x52, (byte)0x02, (byte)0x83, (byte)0xef, (byte)0xcc,
(byte)0x55, (byte)0xfc, (byte)0xa5, (byte)0xe6, (byte)0x70,
(byte)0x75, (byte)0xb9, (byte)0x04, (byte)0x00, (byte)0x7f,
(byte)0x18, (byte)0x81, (byte)0xd1, (byte)0x51, (byte)0xaf,
(byte)0x76, (byte)0xdf, (byte)0x18, (byte)0xc5, (byte)0x1d,
(byte)0x29, (byte)0xd3, (byte)0x4b };
byte[] aliceEphemeralPrivate = { (byte)0xd1, (byte)0xba, (byte)0x38, (byte)0xce, (byte)0xa9,
(byte)0x17, (byte)0x43, (byte)0xd3, (byte)0x39, (byte)0x39,
(byte)0xc3, (byte)0x3c, (byte)0x84, (byte)0x98, (byte)0x65,
(byte)0x09, (byte)0x28, (byte)0x01, (byte)0x61, (byte)0xb8,
(byte)0xb6, (byte)0x0f, (byte)0xc7, (byte)0x87, (byte)0x0c,
(byte)0x59, (byte)0x9c, (byte)0x1d, (byte)0x46, (byte)0x20,
(byte)0x12, (byte)0x48 };
byte[] aliceIdentityPublic = { (byte)0x05, (byte)0xb4, (byte)0xa8, (byte)0x45, (byte)0x56,
(byte)0x60, (byte)0xad, (byte)0xa6, (byte)0x5b, (byte)0x40,
(byte)0x10, (byte)0x07, (byte)0xf6, (byte)0x15, (byte)0xe6,
(byte)0x54, (byte)0x04, (byte)0x17, (byte)0x46, (byte)0x43,
(byte)0x2e, (byte)0x33, (byte)0x39, (byte)0xc6, (byte)0x87,
(byte)0x51, (byte)0x49, (byte)0xbc, (byte)0xee, (byte)0xfc,
(byte)0xb4, (byte)0x2b, (byte)0x4a };
byte[] aliceIdentityPrivate = { (byte)0x90, (byte)0x40, (byte)0xf0, (byte)0xd4, (byte)0xe0,
(byte)0x9c, (byte)0xf3, (byte)0x8f, (byte)0x6d, (byte)0xc7,
(byte)0xc1, (byte)0x37, (byte)0x79, (byte)0xc9, (byte)0x08,
(byte)0xc0, (byte)0x15, (byte)0xa1, (byte)0xda, (byte)0x4f,
(byte)0xa7, (byte)0x87, (byte)0x37, (byte)0xa0, (byte)0x80,
(byte)0xeb, (byte)0x0a, (byte)0x6f, (byte)0x4f, (byte)0x5f,
(byte)0x8f, (byte)0x58 };
byte[] receiverChain = { (byte)0x97, (byte)0x97, (byte)0xca, (byte)0xca, (byte)0x53,
(byte)0xc9, (byte)0x89, (byte)0xbb, (byte)0xe2, (byte)0x29,
(byte)0xa4, (byte)0x0c, (byte)0xa7, (byte)0x72, (byte)0x70,
(byte)0x10, (byte)0xeb, (byte)0x26, (byte)0x04, (byte)0xfc,
(byte)0x14, (byte)0x94, (byte)0x5d, (byte)0x77, (byte)0x95,
(byte)0x8a, (byte)0x0a, (byte)0xed, (byte)0xa0, (byte)0x88,
(byte)0xb4, (byte)0x4d };
IdentityKey bobIdentityKey = new IdentityKey(bobIdentityPublic, 0);
IEcPublicKey bobEphemeralPublicKey = Curve.DecodePoint(bobPublic, 0);
IEcPublicKey bobSignedPreKey = Curve.DecodePoint(bobSignedPreKeyPublic, 0);
IEcPublicKey aliceBasePublicKey = Curve.DecodePoint(aliceBasePublic, 0);
IEcPrivateKey aliceBasePrivateKey = Curve.DecodePrivatePoint(aliceBasePrivate);
EcKeyPair aliceBaseKey = new EcKeyPair(aliceBasePublicKey, aliceBasePrivateKey);
IEcPublicKey aliceEphemeralPublicKey = Curve.DecodePoint(aliceEphemeralPublic, 0);
IEcPrivateKey aliceEphemeralPrivateKey = Curve.DecodePrivatePoint(aliceEphemeralPrivate);
EcKeyPair aliceEphemeralKey = new EcKeyPair(aliceEphemeralPublicKey, aliceEphemeralPrivateKey);
IdentityKey aliceIdentityPublicKey = new IdentityKey(aliceIdentityPublic, 0);
IEcPrivateKey aliceIdentityPrivateKey = Curve.DecodePrivatePoint(aliceIdentityPrivate);
IdentityKeyPair aliceIdentityKey = new IdentityKeyPair(aliceIdentityPublicKey, aliceIdentityPrivateKey);
SessionState session = new SessionState();
AliceSignalProtocolParameters parameters = AliceSignalProtocolParameters.NewBuilder()
.SetOurBaseKey(aliceBaseKey)
.SetOurIdentityKey(aliceIdentityKey)
.SetTheirIdentityKey(bobIdentityKey)
.SetTheirSignedPreKey(bobSignedPreKey)
.SetTheirRatchetKey(bobEphemeralPublicKey)
.SetTheirOneTimePreKey(May <IEcPublicKey> .NoValue)
.Create();
RatchetingSession.InitializeSession(session, parameters);
Assert.AreEqual <IdentityKey>(session.GetLocalIdentityKey(), aliceIdentityKey.GetPublicKey());
Assert.AreEqual <IdentityKey>(session.GetRemoteIdentityKey(), bobIdentityKey);
CollectionAssert.AreEqual(
session.GetReceiverChainKey(bobEphemeralPublicKey).GetKey(), receiverChain);
}