@@ -3,6 +3,8 @@ package eu.siacs.conversations.crypto.axolotl;
import android.util.Base64;
import android.util.Log;
+import org.whispersystems.libaxolotl.protocol.CiphertextMessage;
+
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
@@ -41,7 +43,7 @@ public class XmppAxolotlMessage {
private byte[] innerKey;
private byte[] ciphertext = null;
private byte[] iv = null;
- private final Map<Integer, byte[]> keys;
+ private final Map<Integer, XmppAxolotlSession.AxolotlKey> keys;
private final Jid from;
private final int sourceDeviceId;
@@ -104,7 +106,8 @@ public class XmppAxolotlMessage {
try {
Integer recipientId = Integer.parseInt(keyElement.getAttribute(REMOTEID));
byte[] key = Base64.decode(keyElement.getContent().trim(), Base64.DEFAULT);
- this.keys.put(recipientId, key);
+ boolean isPreKey =keyElement.getAttributeAsBoolean("prekey");
+ this.keys.put(recipientId, new XmppAxolotlSession.AxolotlKey(key,isPreKey));
} catch (NumberFormatException e) {
throw new IllegalArgumentException("invalid remote id");
}
@@ -199,7 +202,7 @@ public class XmppAxolotlMessage {
}
public void addDevice(XmppAxolotlSession session) {
- byte[] key = session.processSending(innerKey);
+ XmppAxolotlSession.AxolotlKey key = session.processSending(innerKey);
if (key != null) {
keys.put(session.getRemoteAddress().getDeviceId(), key);
}
@@ -217,10 +220,13 @@ public class XmppAxolotlMessage {
Element encryptionElement = new Element(CONTAINERTAG, AxolotlService.PEP_PREFIX);
Element headerElement = encryptionElement.addChild(HEADER);
headerElement.setAttribute(SOURCEID, sourceDeviceId);
- for (Map.Entry<Integer, byte[]> keyEntry : keys.entrySet()) {
+ for (Map.Entry<Integer, XmppAxolotlSession.AxolotlKey> keyEntry : keys.entrySet()) {
Element keyElement = new Element(KEYTAG);
keyElement.setAttribute(REMOTEID, keyEntry.getKey());
- keyElement.setContent(Base64.encodeToString(keyEntry.getValue(), Base64.NO_WRAP));
+ if (keyEntry.getValue().prekey) {
+ keyElement.setAttribute("prekey","true");
+ }
+ keyElement.setContent(Base64.encodeToString(keyEntry.getValue().key, Base64.NO_WRAP));
headerElement.addChild(keyElement);
}
headerElement.addChild(IVTAG).setContent(Base64.encodeToString(iv, Base64.NO_WRAP));
@@ -232,7 +238,7 @@ public class XmppAxolotlMessage {
}
private byte[] unpackKey(XmppAxolotlSession session, Integer sourceDeviceId) {
- byte[] encryptedKey = keys.get(sourceDeviceId);
+ XmppAxolotlSession.AxolotlKey encryptedKey = keys.get(sourceDeviceId);
return (encryptedKey != null) ? session.processReceiving(encryptedKey) : null;
}
@@ -82,13 +82,13 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
}
@Nullable
- public byte[] processReceiving(byte[] encryptedKey) {
+ public byte[] processReceiving(AxolotlKey encryptedKey) {
byte[] plaintext = null;
FingerprintStatus status = getTrust();
if (!status.isCompromised()) {
try {
try {
- PreKeyWhisperMessage message = new PreKeyWhisperMessage(encryptedKey);
+ PreKeyWhisperMessage message = new PreKeyWhisperMessage(encryptedKey.key);
if (!message.getPreKeyId().isPresent()) {
Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "PreKeyWhisperMessage did not contain a PreKeyId");
return null;
@@ -104,7 +104,7 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
}
} catch (InvalidMessageException | InvalidVersionException e) {
Log.i(Config.LOGTAG, AxolotlService.getLogprefix(account) + "WhisperMessage received");
- WhisperMessage message = new WhisperMessage(encryptedKey);
+ WhisperMessage message = new WhisperMessage(encryptedKey.key);
plaintext = cipher.decrypt(message);
} catch (InvalidKeyException | InvalidKeyIdException | UntrustedIdentityException e) {
Log.w(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Error decrypting axolotl header, " + e.getClass().getName() + ": " + e.getMessage());
@@ -123,11 +123,11 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
}
@Nullable
- public byte[] processSending(@NonNull byte[] outgoingMessage) {
+ public AxolotlKey processSending(@NonNull byte[] outgoingMessage) {
FingerprintStatus status = getTrust();
if (status.isTrustedAndActive()) {
CiphertextMessage ciphertextMessage = cipher.encrypt(outgoingMessage);
- return ciphertextMessage.serialize();
+ return new AxolotlKey(ciphertextMessage.serialize(),ciphertextMessage.getType() == CiphertextMessage.PREKEY_TYPE);
} else {
return null;
}
@@ -141,4 +141,16 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
public int compareTo(XmppAxolotlSession o) {
return getTrust().compareTo(o.getTrust());
}
+
+ public static class AxolotlKey {
+
+
+ public final byte[] key;
+ public final boolean prekey;
+
+ public AxolotlKey(byte[] key, boolean prekey) {
+ this.key = key;
+ this.prekey = prekey;
+ }
+ }
}