diff options
Diffstat (limited to 'src/main/java/eu/siacs/conversations/crypto/OtrEngine.java')
| -rw-r--r-- | src/main/java/eu/siacs/conversations/crypto/OtrEngine.java | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/src/main/java/eu/siacs/conversations/crypto/OtrEngine.java b/src/main/java/eu/siacs/conversations/crypto/OtrEngine.java new file mode 100644 index 00000000..e0bd0e79 --- /dev/null +++ b/src/main/java/eu/siacs/conversations/crypto/OtrEngine.java @@ -0,0 +1,231 @@ +package eu.siacs.conversations.crypto; + +import java.math.BigInteger; +import java.security.KeyFactory; +import java.security.KeyPair; +import java.security.KeyPairGenerator; +import java.security.NoSuchAlgorithmException; +import java.security.PrivateKey; +import java.security.PublicKey; +import java.security.spec.DSAPrivateKeySpec; +import java.security.spec.DSAPublicKeySpec; +import java.security.spec.InvalidKeySpecException; + +import org.json.JSONException; +import org.json.JSONObject; + +import android.util.Log; + +import eu.siacs.conversations.Config; +import eu.siacs.conversations.entities.Account; +import eu.siacs.conversations.services.XmppConnectionService; +import eu.siacs.conversations.xmpp.stanzas.MessagePacket; + +import net.java.otr4j.OtrEngineHost; +import net.java.otr4j.OtrException; +import net.java.otr4j.OtrPolicy; +import net.java.otr4j.OtrPolicyImpl; +import net.java.otr4j.session.InstanceTag; +import net.java.otr4j.session.SessionID; + +public class OtrEngine implements OtrEngineHost { + + private Account account; + private OtrPolicy otrPolicy; + private KeyPair keyPair; + private XmppConnectionService mXmppConnectionService; + + public OtrEngine(XmppConnectionService service, Account account) { + this.account = account; + this.otrPolicy = new OtrPolicyImpl(); + this.otrPolicy.setAllowV1(false); + this.otrPolicy.setAllowV2(true); + this.otrPolicy.setAllowV3(true); + this.keyPair = loadKey(account.getKeys()); + this.mXmppConnectionService = service; + } + + private KeyPair loadKey(JSONObject keys) { + if (keys == null) { + return null; + } + try { + BigInteger x = new BigInteger(keys.getString("otr_x"), 16); + BigInteger y = new BigInteger(keys.getString("otr_y"), 16); + BigInteger p = new BigInteger(keys.getString("otr_p"), 16); + BigInteger q = new BigInteger(keys.getString("otr_q"), 16); + BigInteger g = new BigInteger(keys.getString("otr_g"), 16); + KeyFactory keyFactory = KeyFactory.getInstance("DSA"); + DSAPublicKeySpec pubKeySpec = new DSAPublicKeySpec(y, p, q, g); + DSAPrivateKeySpec privateKeySpec = new DSAPrivateKeySpec(x, p, q, g); + PublicKey publicKey = keyFactory.generatePublic(pubKeySpec); + PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec); + return new KeyPair(publicKey, privateKey); + } catch (JSONException e) { + return null; + } catch (NoSuchAlgorithmException e) { + return null; + } catch (InvalidKeySpecException e) { + return null; + } + } + + private void saveKey() { + PublicKey publicKey = keyPair.getPublic(); + PrivateKey privateKey = keyPair.getPrivate(); + KeyFactory keyFactory; + try { + keyFactory = KeyFactory.getInstance("DSA"); + DSAPrivateKeySpec privateKeySpec = keyFactory.getKeySpec( + privateKey, DSAPrivateKeySpec.class); + DSAPublicKeySpec publicKeySpec = keyFactory.getKeySpec(publicKey, + DSAPublicKeySpec.class); + this.account.setKey("otr_x", privateKeySpec.getX().toString(16)); + this.account.setKey("otr_g", privateKeySpec.getG().toString(16)); + this.account.setKey("otr_p", privateKeySpec.getP().toString(16)); + this.account.setKey("otr_q", privateKeySpec.getQ().toString(16)); + this.account.setKey("otr_y", publicKeySpec.getY().toString(16)); + } catch (NoSuchAlgorithmException e) { + e.printStackTrace(); + } catch (InvalidKeySpecException e) { + e.printStackTrace(); + } + + } + + @Override + public void askForSecret(SessionID arg0, InstanceTag arg1, String arg2) { + // TODO Auto-generated method stub + + } + + @Override + public void finishedSessionMessage(SessionID arg0, String arg1) + throws OtrException { + + } + + @Override + public String getFallbackMessage(SessionID arg0) { + return "I would like to start a private (OTR encrypted) conversation but your client doesn’t seem to support that"; + } + + @Override + public byte[] getLocalFingerprintRaw(SessionID arg0) { + // TODO Auto-generated method stub + return null; + } + + public PublicKey getPublicKey() { + if (this.keyPair == null) { + return null; + } + return this.keyPair.getPublic(); + } + + @Override + public KeyPair getLocalKeyPair(SessionID arg0) throws OtrException { + if (this.keyPair == null) { + KeyPairGenerator kg; + try { + kg = KeyPairGenerator.getInstance("DSA"); + this.keyPair = kg.genKeyPair(); + this.saveKey(); + mXmppConnectionService.databaseBackend.updateAccount(account); + } catch (NoSuchAlgorithmException e) { + Log.d(Config.LOGTAG, + "error generating key pair " + e.getMessage()); + } + } + return this.keyPair; + } + + @Override + public String getReplyForUnreadableMessage(SessionID arg0) { + // TODO Auto-generated method stub + return null; + } + + @Override + public OtrPolicy getSessionPolicy(SessionID arg0) { + return otrPolicy; + } + + @Override + public void injectMessage(SessionID session, String body) + throws OtrException { + MessagePacket packet = new MessagePacket(); + packet.setFrom(account.getFullJid()); + if (session.getUserID().isEmpty()) { + packet.setTo(session.getAccountID()); + } else { + packet.setTo(session.getAccountID() + "/" + session.getUserID()); + } + packet.setBody(body); + packet.addChild("private", "urn:xmpp:carbons:2"); + packet.addChild("no-copy", "urn:xmpp:hints"); + packet.setType(MessagePacket.TYPE_CHAT); + account.getXmppConnection().sendMessagePacket(packet); + } + + @Override + public void messageFromAnotherInstanceReceived(SessionID id) { + Log.d(Config.LOGTAG, + "unreadable message received from " + id.getAccountID()); + } + + @Override + public void multipleInstancesDetected(SessionID arg0) { + // TODO Auto-generated method stub + + } + + @Override + public void requireEncryptedMessage(SessionID arg0, String arg1) + throws OtrException { + // TODO Auto-generated method stub + + } + + @Override + public void showError(SessionID arg0, String arg1) throws OtrException { + // TODO Auto-generated method stub + + } + + @Override + public void smpAborted(SessionID arg0) throws OtrException { + // TODO Auto-generated method stub + + } + + @Override + public void smpError(SessionID arg0, int arg1, boolean arg2) + throws OtrException { + throw new OtrException(new Exception("smp error")); + } + + @Override + public void unencryptedMessageReceived(SessionID arg0, String arg1) + throws OtrException { + throw new OtrException(new Exception("unencrypted message received")); + } + + @Override + public void unreadableMessageReceived(SessionID arg0) throws OtrException { + throw new OtrException(new Exception("unreadable message received")); + } + + @Override + public void unverify(SessionID arg0, String arg1) { + // TODO Auto-generated method stub + + } + + @Override + public void verify(SessionID arg0, String arg1, boolean arg2) { + // TODO Auto-generated method stub + + } + +} |