public function processPreKeyBundle($preKey)
{
/*
:type preKey: PreKeyBundle
*/
if (!$this->identityKeyStore->isTrustedIdentity($this->recipientId, $preKey->getIdentityKey())) {
throw new UntrustedIdentityException();
}
if ($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 && $preKey->getPreKey() == null) {
throw new InvalidKeyException('Both signed and unsigned prekeys are absent!');
}
$supportsV3 = $preKey->getSignedPreKey() != null;
$sessionRecord = $this->sessionStore->loadSession($this->recipientId, $this->deviceId);
$ourBaseKey = Curve::generateKeyPair();
$theirSignedPreKey = $supportsV3 ? $preKey->getSignedPreKey() : $preKey->getPreKey();
$theirOneTimePreKey = $preKey->getPreKey();
$theirOneTimePreKeyId = $theirOneTimePreKey != null ? $preKey->getPreKeyId() : null;
$parameters = new AliceBuilder();
$parameters->setOurBaseKey($ourBaseKey)->setOurIdentityKey($this->identityKeyStore->getIdentityKeyPair())->setTheirIdentityKey($preKey->getIdentityKey())->setTheirSignedPreKey($theirSignedPreKey)->setTheirRatchetKey($theirSignedPreKey)->setTheirOneTimePreKey($supportsV3 ? $theirOneTimePreKey : null);
if (!$sessionRecord->isFresh()) {
$sessionRecord->archiveCurrentState();
}
RatchetingSession::initializeSessionAsAlice($sessionRecord->getSessionState(), $supportsV3 ? 3 : 2, $parameters->create());
$sessionRecord->getSessionState()->setUnacknowledgedPreKeyMessage($theirOneTimePreKeyId, $preKey->getSignedPreKeyId(), $ourBaseKey->getPublicKey());
$sessionRecord->getSessionState()->setLocalRegistrationId($this->identityKeyStore->getLocalRegistrationId());
$sessionRecord->getSessionState()->setRemoteRegistrationId($preKey->getRegistrationId());
$sessionRecord->getSessionState()->setAliceBaseKey($ourBaseKey->getPublicKey()->serialize());
$this->sessionStore->storeSession($this->recipientId, $this->deviceId, $sessionRecord);
$this->identityKeyStore->saveIdentity($this->recipientId, $preKey->getIdentityKey());
}
protected function initializeSessionsV3($aliceSessionState, $bobSessionState)
{
$aliceIdentityKeyPair = Curve::generateKeyPair();
$aliceIdentityKey = new IdentityKeyPair(new IdentityKey($aliceIdentityKeyPair->getPublicKey()), $aliceIdentityKeyPair->getPrivateKey());
$aliceBaseKey = Curve::generateKeyPair();
$aliceEphemeralKey = Curve::generateKeyPair();
$alicePreKey = $aliceBaseKey;
$bobIdentityKeyPair = Curve::generateKeyPair();
$bobIdentityKey = new IdentityKeyPair(new IdentityKey($bobIdentityKeyPair->getPublicKey()), $bobIdentityKeyPair->getPrivateKey());
$bobBaseKey = Curve::generateKeyPair();
$bobEphemeralKey = $bobBaseKey;
$bobPreKey = Curve::generateKeyPair();
$aliceParameters = AliceAxolotlParameters::newBuilder()->setOurBaseKey($aliceBaseKey)->setOurIdentityKey($aliceIdentityKey)->setTheirOneTimePreKey(null)->setTheirRatchetKey($bobEphemeralKey->getPublicKey())->setTheirSignedPreKey($bobBaseKey->getPublicKey())->setTheirIdentityKey($bobIdentityKey->getPublicKey())->create();
$bobParameters = BobAxolotlParameters::newBuilder()->setOurRatchetKey($bobEphemeralKey)->setOurSignedPreKey($bobBaseKey)->setOurOneTimePreKey(null)->setOurIdentityKey($bobIdentityKey)->setTheirIdentityKey($aliceIdentityKey->getPublicKey())->setTheirBaseKey($aliceBaseKey->getPublicKey())->create();
RatchetingSession::initializeSessionAsAlice($aliceSessionState, 3, $aliceParameters);
RatchetingSession::initializeSessionAsBob($bobSessionState, 3, $bobParameters);
}
