1package eu.siacs.conversations.crypto;
2
3import android.util.Log;
4
5import net.java.otr4j.OtrEngineHost;
6import net.java.otr4j.OtrException;
7import net.java.otr4j.OtrPolicy;
8import net.java.otr4j.OtrPolicyImpl;
9import net.java.otr4j.crypto.OtrCryptoEngineImpl;
10import net.java.otr4j.crypto.OtrCryptoException;
11import net.java.otr4j.session.FragmenterInstructions;
12import net.java.otr4j.session.InstanceTag;
13import net.java.otr4j.session.SessionID;
14
15import org.json.JSONException;
16import org.json.JSONObject;
17
18import java.math.BigInteger;
19import java.security.KeyFactory;
20import java.security.KeyPair;
21import java.security.KeyPairGenerator;
22import java.security.NoSuchAlgorithmException;
23import java.security.PrivateKey;
24import java.security.PublicKey;
25import java.security.spec.DSAPrivateKeySpec;
26import java.security.spec.DSAPublicKeySpec;
27import java.security.spec.InvalidKeySpecException;
28
29import eu.siacs.conversations.Config;
30import eu.siacs.conversations.entities.Account;
31import eu.siacs.conversations.entities.Conversation;
32import eu.siacs.conversations.services.XmppConnectionService;
33import eu.siacs.conversations.xmpp.chatstate.ChatState;
34import eu.siacs.conversations.xmpp.jid.InvalidJidException;
35import eu.siacs.conversations.xmpp.jid.Jid;
36import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
37
38public class OtrService extends OtrCryptoEngineImpl implements OtrEngineHost {
39
40 private Account account;
41 private OtrPolicy otrPolicy;
42 private KeyPair keyPair;
43 private XmppConnectionService mXmppConnectionService;
44
45 public OtrService(XmppConnectionService service, Account account) {
46 this.account = account;
47 this.otrPolicy = new OtrPolicyImpl();
48 this.otrPolicy.setAllowV1(false);
49 this.otrPolicy.setAllowV2(true);
50 this.otrPolicy.setAllowV3(true);
51 this.keyPair = loadKey(account.getKeys());
52 this.mXmppConnectionService = service;
53 }
54
55 private KeyPair loadKey(JSONObject keys) {
56 if (keys == null) {
57 return null;
58 }
59 try {
60 BigInteger x = new BigInteger(keys.getString("otr_x"), 16);
61 BigInteger y = new BigInteger(keys.getString("otr_y"), 16);
62 BigInteger p = new BigInteger(keys.getString("otr_p"), 16);
63 BigInteger q = new BigInteger(keys.getString("otr_q"), 16);
64 BigInteger g = new BigInteger(keys.getString("otr_g"), 16);
65 KeyFactory keyFactory = KeyFactory.getInstance("DSA");
66 DSAPublicKeySpec pubKeySpec = new DSAPublicKeySpec(y, p, q, g);
67 DSAPrivateKeySpec privateKeySpec = new DSAPrivateKeySpec(x, p, q, g);
68 PublicKey publicKey = keyFactory.generatePublic(pubKeySpec);
69 PrivateKey privateKey = keyFactory.generatePrivate(privateKeySpec);
70 return new KeyPair(publicKey, privateKey);
71 } catch (JSONException e) {
72 return null;
73 } catch (NoSuchAlgorithmException e) {
74 return null;
75 } catch (InvalidKeySpecException e) {
76 return null;
77 }
78 }
79
80 private void saveKey() {
81 PublicKey publicKey = keyPair.getPublic();
82 PrivateKey privateKey = keyPair.getPrivate();
83 KeyFactory keyFactory;
84 try {
85 keyFactory = KeyFactory.getInstance("DSA");
86 DSAPrivateKeySpec privateKeySpec = keyFactory.getKeySpec(
87 privateKey, DSAPrivateKeySpec.class);
88 DSAPublicKeySpec publicKeySpec = keyFactory.getKeySpec(publicKey,
89 DSAPublicKeySpec.class);
90 this.account.setKey("otr_x", privateKeySpec.getX().toString(16));
91 this.account.setKey("otr_g", privateKeySpec.getG().toString(16));
92 this.account.setKey("otr_p", privateKeySpec.getP().toString(16));
93 this.account.setKey("otr_q", privateKeySpec.getQ().toString(16));
94 this.account.setKey("otr_y", publicKeySpec.getY().toString(16));
95 } catch (final NoSuchAlgorithmException | InvalidKeySpecException e) {
96 e.printStackTrace();
97 }
98
99 }
100
101 @Override
102 public void askForSecret(SessionID id, InstanceTag instanceTag, String question) {
103 try {
104 final Jid jid = Jid.fromSessionID(id);
105 Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
106 if (conversation!=null) {
107 conversation.smp().hint = question;
108 conversation.smp().status = Conversation.Smp.STATUS_CONTACT_REQUESTED;
109 mXmppConnectionService.updateConversationUi();
110 }
111 } catch (InvalidJidException e) {
112 Log.d(Config.LOGTAG,account.getJid().toBareJid()+": smp in invalid session "+id.toString());
113 }
114 }
115
116 @Override
117 public void finishedSessionMessage(SessionID arg0, String arg1)
118 throws OtrException {
119
120 }
121
122 @Override
123 public String getFallbackMessage(SessionID arg0) {
124 return "I would like to start a private (OTR encrypted) conversation but your client doesn’t seem to support that";
125 }
126
127 @Override
128 public byte[] getLocalFingerprintRaw(SessionID arg0) {
129 try {
130 return getFingerprintRaw(getPublicKey());
131 } catch (OtrCryptoException e) {
132 return null;
133 }
134 }
135
136 public PublicKey getPublicKey() {
137 if (this.keyPair == null) {
138 return null;
139 }
140 return this.keyPair.getPublic();
141 }
142
143 @Override
144 public KeyPair getLocalKeyPair(SessionID arg0) throws OtrException {
145 if (this.keyPair == null) {
146 KeyPairGenerator kg;
147 try {
148 kg = KeyPairGenerator.getInstance("DSA");
149 this.keyPair = kg.genKeyPair();
150 this.saveKey();
151 mXmppConnectionService.databaseBackend.updateAccount(account);
152 } catch (NoSuchAlgorithmException e) {
153 Log.d(Config.LOGTAG,
154 "error generating key pair " + e.getMessage());
155 }
156 }
157 return this.keyPair;
158 }
159
160 @Override
161 public String getReplyForUnreadableMessage(SessionID arg0) {
162 // TODO Auto-generated method stub
163 return null;
164 }
165
166 @Override
167 public OtrPolicy getSessionPolicy(SessionID arg0) {
168 return otrPolicy;
169 }
170
171 @Override
172 public void injectMessage(SessionID session, String body)
173 throws OtrException {
174 MessagePacket packet = new MessagePacket();
175 packet.setFrom(account.getJid());
176 if (session.getUserID().isEmpty()) {
177 packet.setAttribute("to", session.getAccountID());
178 } else {
179 packet.setAttribute("to", session.getAccountID() + "/" + session.getUserID());
180 }
181 packet.setBody(body);
182 packet.addChild("private", "urn:xmpp:carbons:2");
183 packet.addChild("no-copy", "urn:xmpp:hints");
184 packet.addChild("no-permanent-store", "urn:xmpp:hints");
185 packet.addChild("no-permanent-storage", "urn:xmpp:hints");
186 try {
187 Jid jid = Jid.fromSessionID(session);
188 Conversation conversation = mXmppConnectionService.find(account,jid);
189 if (conversation != null && conversation.setOutgoingChatState(Config.DEFAULT_CHATSTATE)) {
190 if (mXmppConnectionService.sendChatStates()) {
191 packet.addChild(ChatState.toElement(conversation.getOutgoingChatState()));
192 }
193 }
194 } catch (final InvalidJidException ignored) {
195
196 }
197
198 packet.setType(MessagePacket.TYPE_CHAT);
199 account.getXmppConnection().sendMessagePacket(packet);
200 }
201
202 @Override
203 public void messageFromAnotherInstanceReceived(SessionID session) {
204 sendOtrErrorMessage(session, "Message from another OTR-instance received");
205 }
206
207 @Override
208 public void multipleInstancesDetected(SessionID arg0) {
209 // TODO Auto-generated method stub
210
211 }
212
213 @Override
214 public void requireEncryptedMessage(SessionID arg0, String arg1)
215 throws OtrException {
216 // TODO Auto-generated method stub
217
218 }
219
220 @Override
221 public void showError(SessionID arg0, String arg1) throws OtrException {
222 Log.d(Config.LOGTAG,"show error");
223 }
224
225 @Override
226 public void smpAborted(SessionID id) throws OtrException {
227 setSmpStatus(id, Conversation.Smp.STATUS_NONE);
228 }
229
230 private void setSmpStatus(SessionID id, int status) {
231 try {
232 final Jid jid = Jid.fromSessionID(id);
233 Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
234 if (conversation!=null) {
235 conversation.smp().status = status;
236 mXmppConnectionService.updateConversationUi();
237 }
238 } catch (final InvalidJidException ignored) {
239
240 }
241 }
242
243 @Override
244 public void smpError(SessionID id, int arg1, boolean arg2)
245 throws OtrException {
246 setSmpStatus(id, Conversation.Smp.STATUS_NONE);
247 }
248
249 @Override
250 public void unencryptedMessageReceived(SessionID arg0, String arg1)
251 throws OtrException {
252 throw new OtrException(new Exception("unencrypted message received"));
253 }
254
255 @Override
256 public void unreadableMessageReceived(SessionID session) throws OtrException {
257 Log.d(Config.LOGTAG,"unreadable message received");
258 sendOtrErrorMessage(session, "You sent me an unreadable OTR-encrypted message");
259 }
260
261 public void sendOtrErrorMessage(SessionID session, String errorText) {
262 try {
263 Jid jid = Jid.fromSessionID(session);
264 Conversation conversation = mXmppConnectionService.find(account, jid);
265 String id = conversation == null ? null : conversation.getLastReceivedOtrMessageId();
266 if (id != null) {
267 MessagePacket packet = mXmppConnectionService.getMessageGenerator()
268 .generateOtrError(jid, id, errorText);
269 packet.setFrom(account.getJid());
270 mXmppConnectionService.sendMessagePacket(account,packet);
271 Log.d(Config.LOGTAG,packet.toString());
272 Log.d(Config.LOGTAG,account.getJid().toBareJid().toString()
273 +": unreadable OTR message in "+conversation.getName());
274 }
275 } catch (InvalidJidException e) {
276 return;
277 }
278 }
279
280 @Override
281 public void unverify(SessionID id, String arg1) {
282 setSmpStatus(id, Conversation.Smp.STATUS_FAILED);
283 }
284
285 @Override
286 public void verify(SessionID id, String fingerprint, boolean approved) {
287 Log.d(Config.LOGTAG,"OtrService.verify("+id.toString()+","+fingerprint+","+String.valueOf(approved)+")");
288 try {
289 final Jid jid = Jid.fromSessionID(id);
290 Conversation conversation = this.mXmppConnectionService.find(this.account,jid);
291 if (conversation!=null) {
292 if (approved) {
293 conversation.getContact().addOtrFingerprint(fingerprint);
294 }
295 conversation.smp().hint = null;
296 conversation.smp().status = Conversation.Smp.STATUS_VERIFIED;
297 mXmppConnectionService.updateConversationUi();
298 mXmppConnectionService.syncRosterToDisk(conversation.getAccount());
299 }
300 } catch (final InvalidJidException ignored) {
301 }
302 }
303
304 @Override
305 public FragmenterInstructions getFragmenterInstructions(SessionID sessionID) {
306 return null;
307 }
308
309}