1 files changed, 54 insertions, 26 deletions
diff --git a/src/main/java/de/pixart/messenger/crypto/axolotl/XmppAxolotlSession.java b/src/main/java/de/pixart/messenger/crypto/axolotl/XmppAxolotlSession.java
index cbfdaf28e..71e20676e 100644
--- a/src/main/java/de/pixart/messenger/crypto/axolotl/XmppAxolotlSession.java
+++ b/src/main/java/de/pixart/messenger/crypto/axolotl/XmppAxolotlSession.java
@@ -2,6 +2,7 @@ package de.pixart.messenger.crypto.axolotl;
 
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
+import android.util.Log;
 
 import org.whispersystems.libsignal.DuplicateMessageException;
 import org.whispersystems.libsignal.IdentityKey;
@@ -19,6 +20,10 @@ import org.whispersystems.libsignal.protocol.PreKeySignalMessage;
 import org.whispersystems.libsignal.protocol.SignalMessage;
 import org.whispersystems.libsignal.util.guava.Optional;
 
+import java.util.Iterator;
+import java.util.List;
+
+import de.pixart.messenger.Config;
 import de.pixart.messenger.entities.Account;
 import de.pixart.messenger.utils.CryptoHelper;
 
@@ -79,35 +84,56 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
     }
 
     @Nullable
-    byte[] processReceiving(AxolotlKey encryptedKey) throws CryptoFailedException {
-        byte[] plaintext;
+    byte[] processReceiving(List<AxolotlKey> possibleKeys) throws CryptoFailedException {
+        byte[] plaintext = null;
         FingerprintStatus status = getTrust();
         if (!status.isCompromised()) {
-            try {
-                if (encryptedKey.prekey) {
-                    PreKeySignalMessage preKeySignalMessage = new PreKeySignalMessage(encryptedKey.key);
-                    Optional<Integer> optionalPreKeyId = preKeySignalMessage.getPreKeyId();
-                    IdentityKey identityKey = preKeySignalMessage.getIdentityKey();
-                    if (!optionalPreKeyId.isPresent()) {
-                        throw new CryptoFailedException("PreKeyWhisperMessage did not contain a PreKeyId");
+            Iterator<AxolotlKey> iterator = possibleKeys.iterator();
+            while (iterator.hasNext()) {
+                AxolotlKey encryptedKey = iterator.next();
+                try {
+                    if (encryptedKey.prekey) {
+                        PreKeySignalMessage preKeySignalMessage = new PreKeySignalMessage(encryptedKey.key);
+                        Optional<Integer> optionalPreKeyId = preKeySignalMessage.getPreKeyId();
+                        IdentityKey identityKey = preKeySignalMessage.getIdentityKey();
+                        if (!optionalPreKeyId.isPresent()) {
+                            if (iterator.hasNext()) {
+                                continue;
+                            }
+                            throw new CryptoFailedException("PreKeyWhisperMessage did not contain a PreKeyId");
+                        }
+                        preKeyId = optionalPreKeyId.get();
+                        if (this.identityKey != null && !this.identityKey.equals(identityKey)) {
+                            if (iterator.hasNext()) {
+                                continue;
+                            }
+                            throw new CryptoFailedException("Received PreKeyWhisperMessage but preexisting identity key changed.");
+                        }
+                        this.identityKey = identityKey;
+                        plaintext = cipher.decrypt(preKeySignalMessage);
+                    } else {
+                        SignalMessage signalMessage = new SignalMessage(encryptedKey.key);
+                        try {
+                            plaintext = cipher.decrypt(signalMessage);
+                        } catch (InvalidMessageException | NoSessionException e) {
+                            if (iterator.hasNext()) {
+                                Log.w(Config.LOGTAG, account.getJid().asBareJid() + ": ignoring crypto exception because possible keys left to try", e);
+                                continue;
+                            }
+                            throw new BrokenSessionException(this.remoteAddress, e);
+                        }
+                        preKeyId = null; //better safe than sorry because we use that to do special after prekey handling
                     }
-                    preKeyId = optionalPreKeyId.get();
-                    if (this.identityKey != null && !this.identityKey.equals(identityKey)) {
-                        throw new CryptoFailedException("Received PreKeyWhisperMessage but preexisting identity key changed.");
+                } catch (InvalidVersionException | InvalidKeyException | LegacyMessageException | InvalidMessageException | DuplicateMessageException | InvalidKeyIdException | UntrustedIdentityException e) {
+                    if (iterator.hasNext()) {
+                        Log.w(Config.LOGTAG, account.getJid().asBareJid() + ": ignoring crypto exception because possible keys left to try", e);
+                        continue;
                     }
-                    this.identityKey = identityKey;
-                    plaintext = cipher.decrypt(preKeySignalMessage);
-                } else {
-                    SignalMessage signalMessage = new SignalMessage(encryptedKey.key);
-                    try {
-                        plaintext = cipher.decrypt(signalMessage);
-                    } catch (InvalidMessageException | NoSessionException e) {
-                        throw new BrokenSessionException(this.remoteAddress, e);
-                    }
-                    preKeyId = null; //better safe than sorry because we use that to do special after prekey handling
+                    throw new CryptoFailedException("Error decrypting SignalMessage", e);
+                }
+                if (iterator.hasNext()) {
+                    break;
                 }
-            } catch (InvalidVersionException | InvalidKeyException | LegacyMessageException | InvalidMessageException | DuplicateMessageException | InvalidKeyIdException | UntrustedIdentityException e) {
-                throw new CryptoFailedException("Error decrypting SignalMessage", e);
             }
             if (!status.isActive()) {
                 setTrust(status.toActive());
@@ -125,7 +151,7 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
         if (ignoreSessionTrust || status.isTrustedAndActive()) {
             try {
                 CiphertextMessage ciphertextMessage = cipher.encrypt(outgoingMessage);
-                return new AxolotlKey(ciphertextMessage.serialize(), ciphertextMessage.getType() == CiphertextMessage.PREKEY_TYPE);
+                return new AxolotlKey(getRemoteAddress().getDeviceId(), ciphertextMessage.serialize(), ciphertextMessage.getType() == CiphertextMessage.PREKEY_TYPE);
             } catch (UntrustedIdentityException e) {
                 return null;
             }
@@ -148,8 +174,10 @@ public class XmppAxolotlSession implements Comparable<XmppAxolotlSession> {
 
         public final byte[] key;
         public final boolean prekey;
+        public final int deviceId;
 
-        public AxolotlKey(byte[] key, boolean prekey) {
+        public AxolotlKey(int deviceId, byte[] key, boolean prekey) {
+            this.deviceId = deviceId;
             this.key = key;
             this.prekey = prekey;
         }