diff options
Diffstat (limited to 'src/de/gultsch/chat/crypto')
| -rw-r--r-- | src/de/gultsch/chat/crypto/OtrEngine.java | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/src/de/gultsch/chat/crypto/OtrEngine.java b/src/de/gultsch/chat/crypto/OtrEngine.java new file mode 100644 index 00000000..d994f0f9 --- /dev/null +++ b/src/de/gultsch/chat/crypto/OtrEngine.java @@ -0,0 +1,229 @@ +package de.gultsch.chat.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.content.Context; +import android.util.Log; + +import de.gultsch.chat.entities.Account; +import de.gultsch.chat.persistance.DatabaseBackend; +import de.gultsch.chat.xml.Element; +import de.gultsch.chat.xmpp.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 static final String LOGTAG = "xmppService"; + + private Account account; + private OtrPolicy otrPolicy; + private KeyPair keyPair; + private Context context; + + public OtrEngine(Context context, 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()); + } + + 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) { + // TODO Auto-generated catch block + e.printStackTrace(); + } catch (NoSuchAlgorithmException e) { + // TODO Auto-generated catch block + e.printStackTrace(); + } catch (InvalidKeySpecException e) { + // TODO Auto-generated catch block + e.printStackTrace(); + } + 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(); + } catch (JSONException 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 { + // TODO Auto-generated method stub + + } + + @Override + public String getFallbackMessage(SessionID arg0) { + // TODO Auto-generated method stub + return null; + } + + @Override + public byte[] getLocalFingerprintRaw(SessionID arg0) { + // TODO Auto-generated method stub + return null; + } + + @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(); + DatabaseBackend.getInstance(context).updateAccount(account); + } catch (NoSuchAlgorithmException e) { + Log.d(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()); //sender + packet.setTo(session.getAccountID()+"/"+session.getUserID()); //reciepient + packet.setBody(body); + Element privateTag = new Element("private"); + privateTag.setAttribute("xmlns","urn:xmpp:carbons:2"); + packet.addChild(privateTag); + account.getXmppConnection().sendMessagePacket(packet); + } + + @Override + public void messageFromAnotherInstanceReceived(SessionID arg0) { + // TODO Auto-generated method stub + + } + + @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 { + // TODO Auto-generated method stub + + } + + @Override + public void unencryptedMessageReceived(SessionID arg0, String arg1) + throws OtrException { + // TODO Auto-generated method stub + + } + + @Override + public void unreadableMessageReceived(SessionID arg0) throws OtrException { + // TODO Auto-generated method stub + + } + + @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 + + } + +} |