1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
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.entities.Conversation;
import eu.siacs.conversations.entities.Message;
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;
import net.java.otr4j.session.SessionImpl;
import net.java.otr4j.session.SessionStatus;
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) {
String jid = id.getAccountID();
Conversation conversation = mXmppConnectionService
.findOrCreateConversation(account, jid, false);
Message error = new Message(conversation, null, Message.ENCRYPTION_OTR);
conversation.getMessages().add(error);
error.setStatus(Message.STATUS_RECEPTION_FAILED);
mXmppConnectionService.databaseBackend.createMessage(error);
SessionImpl session = conversation.getOtrSession();
if (session != null
&& session.getSessionStatus() != SessionStatus.ENCRYPTED) {
try {
session.startSession();
} catch (OtrException e) {
}
}
}
@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
}
}
|
