public OmemoFingerprintTable(OmemoFingerprint fingerprint, string chatId)
{
this.chatId = chatId;
bareJid = fingerprint.ADDRESS.getName();
deviceId = fingerprint.ADDRESS.getDeviceId();
id = generateId(chatId, bareJid, deviceId);
identityPubKey = fingerprint.IDENTITY_PUB_KEY.serialize();
lastSeen = fingerprint.lastSeen;
trusted = fingerprint.trusted;
}
public void OnFingerprintTrustedChanged(OmemoFingerprint fingerprint)
{
if (fingerprint.trusted)
{
MODEL.TrustedOnly = true;
}
if (!(MODEL.Client is null))
{
OmemoSignalKeyDBManager.INSTANCE.setFingerprint(fingerprint, MODEL.Client.getXMPPAccount().getBareJid());
}
}
private async Task buildSessionForDevicesAsync(OmemoDeviceGroup deviceGroup, IList <OmemoProtocolAddress> devices)
{
if (devices.Count <= 0)
{
return;
}
OmemoProtocolAddress device = devices[0];
devices.RemoveAt(0);
OmemoFingerprint fingerprint = OMEMO_HELPER.OMEMO_STORAGE.LoadFingerprint(device);
// Check if there exists already a session for this device:
OmemoSessionModel session = OMEMO_HELPER.OMEMO_STORAGE.LoadSession(device);
if (session is null)
{
// Try to build a new session by requesting the devices bundle information:
OmemoBundleInformationResultMessage bundleMsg = await requestBundleInformationAsync(device);
if (!(bundleMsg is null) && !(bundleMsg.BUNDLE_INFO.bundle is null))
{
int preKeyIndex = bundleMsg.BUNDLE_INFO.bundle.GetRandomPreKeyIndex();
session = new OmemoSessionModel(bundleMsg.BUNDLE_INFO.bundle, preKeyIndex, CONNECTION.account.omemoIdentityKey);
// Validate fingerprints:
if (fingerprint is null)
{
fingerprint = new OmemoFingerprint(bundleMsg.BUNDLE_INFO.bundle.identityKey, device);
OMEMO_HELPER.OMEMO_STORAGE.StoreFingerprint(fingerprint);
}
else
{
OmemoFingerprint receivedFingerprint = new OmemoFingerprint(bundleMsg.BUNDLE_INFO.bundle.identityKey, device);
// Make sure the fingerprint did not change or somebody is performing an attack:
if (!fingerprint.checkIdentityKey(receivedFingerprint.IDENTITY_KEY))
{
Logger.Warn("[OmemoSessionBuildHelper] Unable to establish session with " + device.ToString() + " - other fingerprint received than stored locally.");
await buildSessionForDevicesAsync(deviceGroup, devices);
return;
}
}
}
else
{
Logger.Warn("[OmemoSessionBuildHelper] Unable to establish session with: " + device.ToString());
}
}
/// <summary>
/// Checks if the fingerprint is trusted by the following mechanism:
/// 1. Does a chat exist for the fingerprint? Yes -> 2. No. -> false
/// 2. Is "trusted keys only" activated for chats? Yes -> 3. No -> true
/// 3. Is the key trusted? Yes -> true No -> false
/// </summary>
/// <param name="fingerprint">The fingerprint we want to check if it's valid.</param>
public bool IsFingerprintTrusted(OmemoFingerprint fingerprint)
{
// Check for own devices:
if (string.Equals(fingerprint.ADDRESS.getName(), ACCOUNT.getBareJid()))
{
// No trust management for own devices right now.
return(true);
}
// Check for contact devices:
else
{
string chatId = ChatTable.generateId(fingerprint.ADDRESS.getName(), ACCOUNT.getBareJid());
ChatTable chat = ChatDBManager.INSTANCE.getChat(chatId);
return(!(chat is null) && (!chat.omemoTrustedKeysOnly || fingerprint.trusted));
}
}
public void OnQrCodeScannerShown(QrCodeScannerDialogDataTemplate model)
{
if (model.Success)
{
Uri uri = null;
try
{
uri = new Uri(model.QrCode);
}
catch (Exception e)
{
Logger.Error("Failed to parse OMEMO fingerprint XMPP URI. Malformed URI: " + model.QrCode, e);
return;
}
if (string.Equals(uri.LocalPath.ToLowerInvariant(), MODEL.Chat.chatJabberId.ToLowerInvariant()))
{
IUriAction action = UriUtils.parse(uri);
if (action is OmemoFingerprintUriAction fingerprintUriAction)
{
OmemoFingerprint fingerprint = OmemoSignalKeyDBManager.INSTANCE.getFingerprint(fingerprintUriAction.FINGERPRINT.ADDRESS, MODEL.Client.getXMPPAccount().getBareJid());
if (fingerprint is null)
{
fingerprint = fingerprintUriAction.FINGERPRINT;
}
fingerprint.trusted = true;
OmemoSignalKeyDBManager.INSTANCE.setFingerprint(fingerprint, MODEL.Client.getXMPPAccount().getBareJid());
Logger.Info("Scanned OMEMO fingerprint successful.");
Logger.Debug("Fingerprint: " + fingerprint.ADDRESS.ToString());
LoadFingerprints();
}
else
{
Logger.Warn("Failed to parse OMEMO fingerprint XMPP URI. Not an " + nameof(OmemoFingerprintUriAction) + ".");
}
}
else
{
Logger.Warn("Failed to parse OMEMO fingerprint XMPP URI. Wrong chat: " + uri.LocalPath);
}
}
}
public void StoreFingerprint(OmemoFingerprint fingerprint)
{
OmemoDeviceModel device;
if (string.Equals(fingerprint.ADDRESS.BARE_JID, dbAccount.bareJid))
{
device = dbAccount.omemoInfo.devices.Where(d => fingerprint.ADDRESS.DEVICE_ID == d.deviceId).FirstOrDefault();
}
else
{
ChatModel chat;
using (SemaLock semaLock = DataCache.INSTANCE.NewChatSemaLock())
{
chat = DataCache.INSTANCE.GetChat(dbAccount.bareJid, fingerprint.ADDRESS.BARE_JID, semaLock);
}
if (chat is null)
{
throw new InvalidOperationException("Failed to store fingerprint. Chat '" + fingerprint.ADDRESS.BARE_JID + "' does not exist.");
}
device = chat.omemoInfo.devices.Where(d => d.deviceId == fingerprint.ADDRESS.DEVICE_ID).FirstOrDefault();
}
if (device is null)
{
throw new InvalidOperationException("Failed to store fingerprint. Device '" + fingerprint.ADDRESS.ToString() + "' does not exist.");
}
if (device.fingerprint is null)
{
device.fingerprint = new OmemoFingerprintModel(fingerprint);
using (MainDbContext ctx = new MainDbContext())
{
ctx.Add(device.fingerprint);
ctx.Update(device);
}
}
else
{
device.fingerprint.lastSeen = fingerprint.lastSeen;
device.fingerprint.trusted = fingerprint.trusted;
device.fingerprint.Update();
}
}
//--------------------------------------------------------Constructor:----------------------------------------------------------------\\
#region --Constructors--
public OmemoFingerprintTrustChangedEventArgs(OmemoFingerprint fingerprint)
{
FINGERPRINT = fingerprint;
}
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 setFingerprint(OmemoFingerprint fingerprint, string accountId)
{
string chatId = ChatTable.generateId(fingerprint.ADDRESS.getName(), accountId);
dB.InsertOrReplace(new OmemoFingerprintTable(fingerprint, chatId));
}
//--------------------------------------------------------Constructor:----------------------------------------------------------------\\
#region --Constructors--
public OmemoFingerprintUriAction(OmemoFingerprint fingerprint)
{
FINGERPRINT = fingerprint;
}
public void StoreFingerprint(OmemoFingerprint fingerprint)
{
FINGERPRINTS[fingerprint.ADDRESS] = fingerprint;
}
public void StoreFingerprint(OmemoFingerprint fingerprint)
{
OmemoSignalKeyDBManager.INSTANCE.setFingerprint(fingerprint, ACCOUNT.getBareJid());
}
