private async Task buildSessionForDevicesAsync(Dictionary <uint, SessionCipher> sessions, IList <SignalProtocolAddress> devices)
{
if (devices.Count <= 0)
{
return;
}
SignalProtocolAddress device = devices[0];
devices.RemoveAt(0);
// Check if there exists already a session for this device:
if (OMEMO_HELPER.OMEMO_STORE.ContainsSession(device))
{
// If yes, the load it:
SessionCipher cipher = OMEMO_HELPER.loadCipher(device);
sessions.Add(device.getDeviceId(), cipher);
Logger.Info("[OmemoSessionBuildHelper] Session for " + device.ToString() + " loaded from cache.");
}
else
{
// Else try to build a new one by requesting the devices bundle information:
OmemoBundleInformationResultMessage bundleMsg = await requestBundleInformationAsync(device);
if (!(bundleMsg is null))
{
SignalProtocolAddress address = OMEMO_HELPER.newSession(CHAT_JID, bundleMsg);
SessionCipher cipher = OMEMO_HELPER.loadCipher(address);
sessions.Add(device.getDeviceId(), cipher);
Logger.Info("[OmemoSessionBuildHelper] Session with " + device.ToString() + " established.");
}
public OmemoDeviceTable(SignalProtocolAddress device, string accountId)
{
this.id = generateId(accountId, device.getName(), device.getDeviceId());
this.accountId = accountId;
this.name = device.getName();
this.deviceId = device.getDeviceId();
}
private void requestBundleInformation()
{
setState(OmemoSessionBuildHelperState.REQUESTING_BUNDLE_INFORMATION);
if (requestBundleInfoHelper != null)
{
requestBundleInfoHelper?.Dispose();
requestBundleInfoHelper = null;
}
requestBundleInfoHelper = new MessageResponseHelper <IQMessage>(CONNECTION, onRequestBundleInformationMessage, onTimeout);
OmemoRequestBundleInformationMessage msg = new OmemoRequestBundleInformationMessage(FULL_ACCOUNT_JID, curAddress.getName(), curAddress.getDeviceId());
requestBundleInfoHelper.start(msg);
}
public OutgoingPushMessage encrypt(SignalProtocolAddress destination, byte[] unpaddedMessage, bool legacy, bool silent)
{
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());
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.getDeviceId(),
remoteRegistrationId,
legacy ? body : null,
legacy ? null : body,
silent));
}
public bool ContainsSession(SignalProtocolAddress address)
{
var name = address.getName();
var deviceId = address.getDeviceId();
var query = conn.Table <Session>().Where(v => v.Name == name && v.DeviceId == deviceId);
return(query.Count() != 0);
}
public void setSession(SignalProtocolAddress address, SessionRecord record, string accountId)
{
dB.InsertOrReplace(new SessionStoreTable()
{
id = SessionStoreTable.generateId(address, accountId),
accountId = accountId,
deviceId = address.getDeviceId(),
name = address.getName(),
session = record.serialize()
});
}
public void StoreSession(SignalProtocolAddress address, SessionRecord record)
{
DeleteSession(address); // TODO: sqlite-net combined private keys for insertOrReplace
var session = new Session()
{
DeviceId = address.getDeviceId(), Name = address.getName(), Record = record.serialize()
};
conn.InsertOrReplace(session);
return;
}
public SessionRecord LoadSession(SignalProtocolAddress address)
{
var name = address.getName();
var deviceId = address.getDeviceId();
var query = conn.Table <Session>().Where(t => t.Name == name && t.DeviceId == deviceId);
if (query != null && query.Any())
{
return(new SessionRecord(query.First().Record));
}
else
{
return(new SessionRecord());
}
}
public void DeleteSession(SignalProtocolAddress address)
{
var name = address.getName();
var deviceId = address.getDeviceId();
var query = conn.Table <Session>().Delete(t => t.Name == name && t.DeviceId == deviceId);
}
public void Test_Omemo_Enc_Dec_1()
{
// Generate Alices keys:
IdentityKeyPair aliceIdentKey = CryptoUtils.generateOmemoIdentityKeyPair();
IList <PreKeyRecord> alicePreKeys = CryptoUtils.generateOmemoPreKeys();
SignedPreKeyRecord aliceSignedPreKey = CryptoUtils.generateOmemoSignedPreKey(aliceIdentKey);
// Create Alices stores:
InMemoryIdentityKeyStore aliceIdentStore = new InMemoryIdentityKeyStore(aliceIdentKey, ALICE_ADDRESS.getDeviceId());
InMemoryPreKeyStore alicePreKeyStore = new InMemoryPreKeyStore();
foreach (PreKeyRecord key in alicePreKeys)
{
alicePreKeyStore.StorePreKey(key.getId(), key);
}
InMemorySignedPreKeyStore aliceSignedPreKeyStore = new InMemorySignedPreKeyStore();
aliceSignedPreKeyStore.StoreSignedPreKey(aliceSignedPreKey.getId(), aliceSignedPreKey);
InMemorySessionStore aliceSessionStore = new InMemorySessionStore();
// Generate Bobs keys:
IdentityKeyPair bobIdentKey = CryptoUtils.generateOmemoIdentityKeyPair();
IList <PreKeyRecord> bobPreKeys = CryptoUtils.generateOmemoPreKeys();
SignedPreKeyRecord bobSignedPreKey = CryptoUtils.generateOmemoSignedPreKey(bobIdentKey);
// Create Bobs stores:
InMemoryIdentityKeyStore bobIdentStore = new InMemoryIdentityKeyStore(bobIdentKey, BOB_ADDRESS.getDeviceId());
InMemoryPreKeyStore bobPreKeyStore = new InMemoryPreKeyStore();
foreach (PreKeyRecord key in bobPreKeys)
{
bobPreKeyStore.StorePreKey(key.getId(), key);
}
InMemorySignedPreKeyStore bobSignedPreKeyStore = new InMemorySignedPreKeyStore();
bobSignedPreKeyStore.StoreSignedPreKey(bobSignedPreKey.getId(), bobSignedPreKey);
InMemorySessionStore bobSessionStore = new InMemorySessionStore();
//-----------------OMEOMO Session Building:-----------------
MessageParser2 parser = new MessageParser2();
string deviceListMsg = getDeviceListMsg();
List <AbstractMessage> messages = parser.parseMessages(ref deviceListMsg);
Assert.IsTrue(messages.Count == 1);
Assert.IsTrue(messages[0] is OmemoDeviceListResultMessage);
OmemoDeviceListResultMessage devList = messages[0] as OmemoDeviceListResultMessage;
uint selectedBobDeviceId = devList.DEVICES.getRandomDeviceId();
Assert.IsTrue(selectedBobDeviceId == BOB_ADDRESS.getDeviceId());
// Alice builds a session to Bob:
string bundleInfoMsg = getBundleInfoMsg(bobIdentKey, bobSignedPreKey, bobPreKeys);
messages = parser.parseMessages(ref bundleInfoMsg);
Assert.IsTrue(messages.Count == 1);
Assert.IsTrue(messages[0] is OmemoBundleInformationResultMessage);
OmemoBundleInformationResultMessage bundleInfo = messages[0] as OmemoBundleInformationResultMessage;
Assert.IsTrue(bundleInfo.DEVICE_ID == BOB_ADDRESS.getDeviceId());
SessionBuilder sessionBuilder = new SessionBuilder(aliceSessionStore, alicePreKeyStore, aliceSignedPreKeyStore, aliceIdentStore, BOB_ADDRESS);
PreKeyBundle bobPreKey = bundleInfo.BUNDLE_INFO.getRandomPreKey(bundleInfo.DEVICE_ID);
sessionBuilder.process(bobPreKey);
// Check if session exists:
Assert.IsTrue(aliceSessionStore.ContainsSession(BOB_ADDRESS));
Assert.IsTrue(aliceSessionStore.LoadSession(BOB_ADDRESS).getSessionState().getSessionVersion() == 3);
// Alice sends a message:
string aliceOrigMsg = "$(rm -rvf .)";
// 1. Generate a new AES-128 GCM key/iv:
Aes128GcmCpp aes128Gcm = new Aes128GcmCpp();
aes128Gcm.generateKey();
aes128Gcm.generateIv();
// 2. Encrypt the message using the Aes128Gcm instance:
byte[] encryptedData = aes128Gcm.encrypt(Encoding.UTF8.GetBytes(aliceOrigMsg));
string base64Payload = Convert.ToBase64String(encryptedData);
string base64IV = Convert.ToBase64String(aes128Gcm.iv);
// 3. Concatenate key and authentication tag:
byte[] keyAuthTag = new byte[aes128Gcm.authTag.Length + aes128Gcm.key.Length];
Buffer.BlockCopy(aes128Gcm.key, 0, keyAuthTag, 0, aes128Gcm.key.Length);
Buffer.BlockCopy(aes128Gcm.authTag, 0, keyAuthTag, aes128Gcm.key.Length, aes128Gcm.authTag.Length);
SessionCipher aliceSessionCipher = new SessionCipher(aliceSessionStore, alicePreKeyStore, aliceSignedPreKeyStore, aliceIdentStore, BOB_ADDRESS);
CiphertextMessage ciphertextMessage = aliceSessionCipher.encrypt(keyAuthTag);
OmemoKey omemoKey = new OmemoKey(BOB_ADDRESS.getDeviceId(), ciphertextMessage is PreKeySignalMessage, Convert.ToBase64String(ciphertextMessage.serialize()));
Assert.IsTrue(string.Equals(Convert.ToBase64String(ciphertextMessage.serialize()), omemoKey.BASE_64_KEY));
//-------------------Decrypt Again:-------------------
// 2. Load the cipher:
SessionCipher cipher = new SessionCipher(bobSessionStore, bobPreKeyStore, bobSignedPreKeyStore, bobIdentStore, ALICE_ADDRESS);
byte[] encryptedKeyAuthTag = Convert.FromBase64String(omemoKey.BASE_64_KEY);
byte[] decryptedKeyAuthTag = null;
if (omemoKey.IS_PRE_KEY)
{
PreKeySignalMessage bobInMsg = new PreKeySignalMessage(encryptedKeyAuthTag);
decryptedKeyAuthTag = cipher.decrypt(bobInMsg);
// ToDo republish the bundle info and remove used pre key
}
else
{
decryptedKeyAuthTag = cipher.decrypt(new SignalMessage(encryptedKeyAuthTag));
}
// 3. Check if the cipher got loaded successfully:
Assert.IsTrue(decryptedKeyAuthTag != null);
// 4. Decrypt the payload:
byte[] aesIv = Convert.FromBase64String(base64IV);
byte[] aesKey = new byte[16];
byte[] aesAuthTag = new byte[decryptedKeyAuthTag.Length - aesKey.Length];
Buffer.BlockCopy(decryptedKeyAuthTag, 0, aesKey, 0, aesKey.Length);
Buffer.BlockCopy(decryptedKeyAuthTag, aesKey.Length, aesAuthTag, 0, aesAuthTag.Length);
aes128Gcm = new Aes128GcmCpp()
{
key = aesKey,
authTag = aesAuthTag,
iv = aesIv
};
encryptedData = Convert.FromBase64String(base64Payload);
byte[] bobData = aes128Gcm.decrypt(encryptedData);
// 5. Convert decrypted data to Unicode string:
string bobRecMsg = Encoding.UTF8.GetString(bobData);
// Check if successfully send:
Assert.AreEqual(aliceOrigMsg, bobRecMsg);
Assert.IsTrue(bobSessionStore.ContainsSession(ALICE_ADDRESS));
}
//--------------------------------------------------------Set-, Get- Methods:---------------------------------------------------------\\
#region --Set-, Get- Methods--
#endregion
//--------------------------------------------------------Misc Methods:---------------------------------------------------------------\\
#region --Misc Methods (Public)--
public static string generateId(SignalProtocolAddress address, string accountId)
{
return(address.getName() + "_" + address.getDeviceId() + "_" + accountId);
}
private async Task buildSessionForDevicesAsync(Dictionary <uint, SessionCipher> sessions, IList <SignalProtocolAddress> devices)
{
if (devices.Count <= 0)
{
return;
}
SignalProtocolAddress device = devices[0];
devices.RemoveAt(0);
// Validate the device fingerprint:
OmemoFingerprint fingerprint = OMEMO_HELPER.OMEMO_STORE.LoadFingerprint(device);
if (!(fingerprint is null) && !OMEMO_HELPER.OMEMO_STORE.IsFingerprintTrusted(fingerprint))
{
Logger.Warn("[OmemoSessionBuildHelper] Not building a session with " + device.ToString() + " - key not trusted.");
await buildSessionForDevicesAsync(sessions, devices);
return;
}
// Check if there exists already a session for this device:
if (OMEMO_HELPER.OMEMO_STORE.ContainsSession(device))
{
// If yes, the load it:
SessionCipher cipher = OMEMO_HELPER.loadCipher(device);
sessions.Add(device.getDeviceId(), cipher);
Logger.Info("[OmemoSessionBuildHelper] Session for " + device.ToString() + " loaded from cache.");
}
else
{
// Else try to build a new one by requesting the devices bundle information:
OmemoBundleInformationResultMessage bundleMsg = await requestBundleInformationAsync(device);
if (!(bundleMsg is null))
{
OMEMO_HELPER.newSession(device.getName(), bundleMsg);
// Validate fingerprints:
if (fingerprint is null)
{
fingerprint = new OmemoFingerprint(bundleMsg.BUNDLE_INFO.PUBLIC_IDENTITY_KEY, device);
OMEMO_HELPER.OMEMO_STORE.StoreFingerprint(fingerprint);
}
else
{
OmemoFingerprint receivedFingerprint = new OmemoFingerprint(bundleMsg.BUNDLE_INFO.PUBLIC_IDENTITY_KEY, device);
// Make sure the fingerprint did not change or somebody is doing an attack:
if (!fingerprint.checkIdentityKey(receivedFingerprint.IDENTITY_PUB_KEY))
{
Logger.Warn("[OmemoSessionBuildHelper] Unable to establish session with " + device.ToString() + " - other fingerprint received than stored locally.");
await buildSessionForDevicesAsync(sessions, devices);
return;
}
}
// Check if the fingerprint is trusted:
if (OMEMO_HELPER.OMEMO_STORE.IsFingerprintTrusted(fingerprint))
{
SessionCipher cipher = OMEMO_HELPER.loadCipher(device);
sessions.Add(device.getDeviceId(), cipher);
Logger.Info("[OmemoSessionBuildHelper] Session with " + device.ToString() + " established.");
}
else
{
Logger.Warn("[OmemoSessionBuildHelper] Unable to establish session with " + device.ToString() + " - key not trusted.");
}
}
public void Test_Libsignal_Enc_Dec_1()
{
// Generate Alices keys:
IdentityKeyPair aliceIdentKey = CryptoUtils.generateOmemoIdentityKeyPair();
IList <PreKeyRecord> alicePreKeys = CryptoUtils.generateOmemoPreKeys();
SignedPreKeyRecord aliceSignedPreKey = CryptoUtils.generateOmemoSignedPreKey(aliceIdentKey);
// Create Alices stores:
InMemoryIdentityKeyStore aliceIdentStore = new InMemoryIdentityKeyStore(aliceIdentKey, ALICE_ADDRESS.getDeviceId());
InMemoryPreKeyStore alicePreKeyStore = new InMemoryPreKeyStore();
foreach (PreKeyRecord key in alicePreKeys)
{
alicePreKeyStore.StorePreKey(key.getId(), key);
}
InMemorySignedPreKeyStore aliceSignedPreKeyStore = new InMemorySignedPreKeyStore();
aliceSignedPreKeyStore.StoreSignedPreKey(aliceSignedPreKey.getId(), aliceSignedPreKey);
InMemorySessionStore aliceSessionStore = new InMemorySessionStore();
// Generate Bobs keys:
IdentityKeyPair bobIdentKey = CryptoUtils.generateOmemoIdentityKeyPair();
IList <PreKeyRecord> bobPreKeys = CryptoUtils.generateOmemoPreKeys();
SignedPreKeyRecord bobSignedPreKey = CryptoUtils.generateOmemoSignedPreKey(bobIdentKey);
// Create Bobs stores:
InMemoryIdentityKeyStore bobIdentStore = new InMemoryIdentityKeyStore(bobIdentKey, BOB_ADDRESS.getDeviceId());
InMemoryPreKeyStore bobPreKeyStore = new InMemoryPreKeyStore();
foreach (PreKeyRecord key in bobPreKeys)
{
bobPreKeyStore.StorePreKey(key.getId(), key);
}
InMemorySignedPreKeyStore bobSignedPreKeyStore = new InMemorySignedPreKeyStore();
bobSignedPreKeyStore.StoreSignedPreKey(bobSignedPreKey.getId(), bobSignedPreKey);
InMemorySessionStore bobSessionStore = new InMemorySessionStore();
// Alice builds a session to Bob:
SessionBuilder sessionBuilder = new SessionBuilder(aliceSessionStore, alicePreKeyStore, aliceSignedPreKeyStore, aliceIdentStore, BOB_ADDRESS);
PreKeyBundle bobPreKey = new PreKeyBundle(BOB_ADDRESS.getDeviceId(), BOB_ADDRESS.getDeviceId(), bobPreKeys[0].getId(), bobPreKeys[0].getKeyPair().getPublicKey(), bobSignedPreKey.getId(), bobSignedPreKey.getKeyPair().getPublicKey(), bobSignedPreKey.getSignature(), bobIdentKey.getPublicKey());
sessionBuilder.process(bobPreKey);
// Check if session exists:
Assert.IsTrue(aliceSessionStore.ContainsSession(BOB_ADDRESS));
Assert.IsTrue(aliceSessionStore.LoadSession(BOB_ADDRESS).getSessionState().getSessionVersion() == 3);
// Alice sends a message:
string aliceOrigMsg = "$(rm -rvf .)";
SessionCipher aliceSessionCipher = new SessionCipher(aliceSessionStore, alicePreKeyStore, aliceSignedPreKeyStore, aliceIdentStore, BOB_ADDRESS);
CiphertextMessage aliceOutMsg = aliceSessionCipher.encrypt(Encoding.UTF8.GetBytes(aliceOrigMsg));
// Check if successfully encrypted:
Assert.IsTrue(aliceOutMsg.getType() == CiphertextMessage.PREKEY_TYPE);
// Bob receives the message:
PreKeySignalMessage bobInMsg = new PreKeySignalMessage(aliceOutMsg.serialize());
SessionCipher bobSessionCipher = new SessionCipher(bobSessionStore, bobPreKeyStore, bobSignedPreKeyStore, bobIdentStore, ALICE_ADDRESS);
byte[] bobData = bobSessionCipher.decrypt(bobInMsg);
string bobRecMsg = Encoding.UTF8.GetString(bobData);
// Check if successfully send:
Assert.AreEqual(aliceOrigMsg, bobRecMsg);
Assert.IsTrue(bobSessionStore.ContainsSession(ALICE_ADDRESS));
}
//--------------------------------------------------------Set-, Get- Methods:---------------------------------------------------------\\
#region --Set-, Get- Methods--
#endregion
//--------------------------------------------------------Misc Methods:---------------------------------------------------------------\\
#region --Misc Methods (Public)--
public static string generateId(string chatId, SignalProtocolAddress address)
{
return(generateId(chatId, address.getName(), address.getDeviceId()));
}
public String serialize()
{
return(groupId + "::" + sender.getName() + "::" + sender.getDeviceId());
}
public int CompareTo(object obj)
{
return(ADDRESS.getName().GetHashCode() ^ ADDRESS.getDeviceId().GetHashCode());
}
