001/**
002 *
003 * Copyright 2017 Paul Schaub
004 *
005 * This file is part of smack-omemo-signal.
006 *
007 * smack-omemo-signal is free software; you can redistribute it and/or modify
008 * it under the terms of the GNU General Public License as published by
009 * the Free Software Foundation; either version 3 of the License, or
010 * (at your option) any later version.
011 *
012 * This program is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
015 * GNU General Public License for more details.
016 *
017 * You should have received a copy of the GNU General Public License
018 * along with this program; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
020 */
021package org.jivesoftware.smackx.omemo.signal;
022
023import java.io.UnsupportedEncodingException;
024import java.security.InvalidAlgorithmParameterException;
025import java.security.InvalidKeyException;
026import java.security.NoSuchAlgorithmException;
027import java.security.NoSuchProviderException;
028import java.util.logging.Level;
029
030import javax.crypto.BadPaddingException;
031import javax.crypto.IllegalBlockSizeException;
032import javax.crypto.NoSuchPaddingException;
033
034import org.jivesoftware.smack.SmackException;
035import org.jivesoftware.smack.XMPPException;
036import org.jivesoftware.smack.XMPPException.XMPPErrorException;
037
038import org.jivesoftware.smackx.omemo.OmemoManager;
039import org.jivesoftware.smackx.omemo.OmemoService;
040import org.jivesoftware.smackx.omemo.OmemoStore;
041import org.jivesoftware.smackx.omemo.exceptions.CorruptedOmemoKeyException;
042import org.jivesoftware.smackx.omemo.internal.OmemoDevice;
043
044import org.whispersystems.libsignal.IdentityKey;
045import org.whispersystems.libsignal.IdentityKeyPair;
046import org.whispersystems.libsignal.SessionBuilder;
047import org.whispersystems.libsignal.SessionCipher;
048import org.whispersystems.libsignal.SignalProtocolAddress;
049import org.whispersystems.libsignal.UntrustedIdentityException;
050import org.whispersystems.libsignal.ecc.ECPublicKey;
051import org.whispersystems.libsignal.state.PreKeyBundle;
052import org.whispersystems.libsignal.state.PreKeyRecord;
053import org.whispersystems.libsignal.state.SessionRecord;
054import org.whispersystems.libsignal.state.SignedPreKeyRecord;
055
056/**
057 * Concrete implementation of the OmemoService using the Signal library.
058 *
059 * @author Paul Schaub
060 */
061@SuppressWarnings("unused")
062public final class SignalOmemoService extends OmemoService<IdentityKeyPair, IdentityKey, PreKeyRecord, SignedPreKeyRecord, SessionRecord, SignalProtocolAddress, ECPublicKey, PreKeyBundle, SessionCipher> {
063
064    private static SignalOmemoService INSTANCE;
065    private static boolean LICENSE_ACKNOWLEDGED = false;
066
067    public static void setup() throws InvalidKeyException, XMPPErrorException, NoSuchPaddingException, InvalidAlgorithmParameterException, UnsupportedEncodingException, IllegalBlockSizeException, BadPaddingException, NoSuchAlgorithmException, NoSuchProviderException, SmackException, InterruptedException, CorruptedOmemoKeyException {
068        if (!LICENSE_ACKNOWLEDGED) {
069            throw new IllegalStateException("smack-omemo-signal is licensed under the terms of the GPLv3. Please be aware that you " +
070                    "can only use this library within the terms of the GPLv3. See for example " +
071                    "https://www.gnu.org/licenses/quick-guide-gplv3 for more details. Please call " +
072                    "SignalOmemoService.acknowledgeLicense() prior to the setup() method in order to prevent " +
073                    "this exception.");
074        }
075        if (INSTANCE == null) {
076            INSTANCE = new SignalOmemoService();
077        }
078        setInstance(INSTANCE);
079    }
080
081    @Override
082    public OmemoStore<IdentityKeyPair, IdentityKey, PreKeyRecord, SignedPreKeyRecord, SessionRecord, SignalProtocolAddress, ECPublicKey, PreKeyBundle, SessionCipher> createDefaultOmemoStoreBackend() {
083        return new SignalFileBasedOmemoStore();
084    }
085
086    private SignalOmemoService()
087            throws SmackException, InterruptedException, XMPPException.XMPPErrorException, CorruptedOmemoKeyException,
088            NoSuchPaddingException, InvalidAlgorithmParameterException, UnsupportedEncodingException,
089            IllegalBlockSizeException, BadPaddingException, NoSuchAlgorithmException, NoSuchProviderException,
090            java.security.InvalidKeyException {
091        super();
092    }
093
094    public static void acknowledgeLicense() {
095        LICENSE_ACKNOWLEDGED = true;
096    }
097
098    @Override
099    protected void processBundle(OmemoManager omemoManager, PreKeyBundle preKeyBundle, OmemoDevice contact) throws CorruptedOmemoKeyException {
100        SignalOmemoStoreConnector connector = new SignalOmemoStoreConnector(omemoManager, getOmemoStoreBackend());
101        SessionBuilder builder = new SessionBuilder(connector, connector, connector, connector,
102                getOmemoStoreBackend().keyUtil().omemoDeviceAsAddress(contact));
103        try {
104            builder.process(preKeyBundle);
105            LOGGER.log(Level.INFO, "Session built with " + contact);
106            getOmemoStoreBackend().getOmemoSessionOf(omemoManager, contact); //method puts session in session map.
107        } catch (org.whispersystems.libsignal.InvalidKeyException e) {
108            throw new CorruptedOmemoKeyException(e.getMessage());
109        } catch (UntrustedIdentityException e) {
110            // This should never happen.
111            throw new AssertionError(e);
112        }
113    }
114}