@Nullable
private XmppAxolotlMessage buildHeader(Contact contact) {
final XmppAxolotlMessage axolotlMessage =
new XmppAxolotlMessage(contact.getJid().toBareJid(), getOwnDeviceId());
Set<XmppAxolotlSession> contactSessions = findSessionsforContact(contact);
Set<XmppAxolotlSession> ownSessions = findOwnSessions();
if (contactSessions.isEmpty()) {
return null;
}
Log.d(
Config.LOGTAG,
AxolotlService.getLogprefix(account) + "Building axolotl foreign keyElements...");
for (XmppAxolotlSession session : contactSessions) {
Log.v(
Config.LOGTAG,
AxolotlService.getLogprefix(account) + session.getRemoteAddress().toString());
axolotlMessage.addDevice(session);
}
Log.d(
Config.LOGTAG,
AxolotlService.getLogprefix(account) + "Building axolotl own keyElements...");
for (XmppAxolotlSession session : ownSessions) {
Log.v(
Config.LOGTAG,
AxolotlService.getLogprefix(account) + session.getRemoteAddress().toString());
axolotlMessage.addDevice(session);
}
return axolotlMessage;
}
private XmppAxolotlSession getReceivingSession(XmppAxolotlMessage message) {
AxolotlAddress senderAddress =
new AxolotlAddress(message.getFrom().toString(), message.getSenderDeviceId());
XmppAxolotlSession session = sessions.get(senderAddress);
if (session == null) {
Log.d(
Config.LOGTAG,
AxolotlService.getLogprefix(account)
+ "Account: "
+ account.getJid()
+ " No axolotl session found while parsing received message "
+ message);
session = recreateUncachedSession(senderAddress);
if (session == null) {
session = new XmppAxolotlSession(account, axolotlStore, senderAddress);
}
}
return session;
}
public XmppAxolotlMessage.XmppAxolotlKeyTransportMessage processReceivingKeyTransportMessage(
XmppAxolotlMessage message) {
XmppAxolotlMessage.XmppAxolotlKeyTransportMessage keyTransportMessage = null;
XmppAxolotlSession session = getReceivingSession(message);
keyTransportMessage = message.getParameters(session, getOwnDeviceId());
if (session.isFresh() && keyTransportMessage != null) {
sessions.put(session);
}
return keyTransportMessage;
}
@Nullable
public XmppAxolotlMessage encrypt(Message message) {
XmppAxolotlMessage axolotlMessage = buildHeader(message.getContact());
if (axolotlMessage != null) {
final String content;
if (message.hasFileOnRemoteHost()) {
content = message.getFileParams().url.toString();
} else {
content = message.getBody();
}
try {
axolotlMessage.encrypt(content);
} catch (CryptoFailedException e) {
Log.w(
Config.LOGTAG, getLogprefix(account) + "Failed to encrypt message: " + e.getMessage());
return null;
}
}
return axolotlMessage;
}
public XmppAxolotlMessage.XmppAxolotlPlaintextMessage processReceivingPayloadMessage(
XmppAxolotlMessage message) {
XmppAxolotlMessage.XmppAxolotlPlaintextMessage plaintextMessage = null;
XmppAxolotlSession session = getReceivingSession(message);
try {
plaintextMessage = message.decrypt(session, getOwnDeviceId());
Integer preKeyId = session.getPreKeyId();
if (preKeyId != null) {
publishBundlesIfNeeded();
session.resetPreKeyId();
}
} catch (CryptoFailedException e) {
Log.w(Config.LOGTAG, getLogprefix(account) + "Failed to decrypt message: " + e.getMessage());
}
if (session.isFresh() && plaintextMessage != null) {
sessions.put(session);
}
return plaintextMessage;
}