More progress on JET

smack-experimental/src/main/java/org/jivesoftware/smackx/ciphers/Aes128GcmNoPadding.java

@@ -0,0 +1,43 @@
+/**
+ *
+ * Copyright 2017 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jivesoftware.smackx.ciphers;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.NoSuchProviderException;
+import javax.crypto.NoSuchPaddingException;
+
+public class Aes128GcmNoPadding extends AesGcmNoPadding {
+    public static final String NAMESPACE = "urn:xmpp:ciphers:aes-128-gcm-nopadding:0";
+
+    public Aes128GcmNoPadding() throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException,
+            NoSuchProviderException, InvalidAlgorithmParameterException {
+        super(128);
+    }
+
+    public Aes128GcmNoPadding(byte[] keyAndIv) throws NoSuchProviderException, InvalidAlgorithmParameterException,
+            NoSuchAlgorithmException, InvalidKeyException, NoSuchPaddingException {
+        super(AesGcmNoPadding.copyOfRange(keyAndIv, 0, keyAndIv.length / 2), //Key
+                AesGcmNoPadding.copyOfRange(keyAndIv, keyAndIv.length / 2, keyAndIv.length / 2)); //IV
+    }
+
+    @Override
+    public String getNamespace() {
+        return NAMESPACE;
+    }
+}

smack-experimental/src/main/java/org/jivesoftware/smackx/ciphers/Aes256GcmNoPadding.java

@@ -0,0 +1,43 @@
+/**
+ *
+ * Copyright 2017 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jivesoftware.smackx.ciphers;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.NoSuchProviderException;
+import javax.crypto.NoSuchPaddingException;
+
+public class Aes256GcmNoPadding extends AesGcmNoPadding {
+    public static final String NAMESPACE = "urn:xmpp:ciphers:aes-256-gcm-nopadding:0";
+
+    public Aes256GcmNoPadding() throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException,
+            NoSuchProviderException, InvalidAlgorithmParameterException {
+        super(256);
+    }
+
+    public Aes256GcmNoPadding(byte[] keyAndIv) throws NoSuchProviderException, InvalidAlgorithmParameterException,
+            NoSuchAlgorithmException, InvalidKeyException, NoSuchPaddingException {
+        super(AesGcmNoPadding.copyOfRange(keyAndIv, 0, keyAndIv.length / 2), //Key
+                AesGcmNoPadding.copyOfRange(keyAndIv, keyAndIv.length / 2, keyAndIv.length / 2)); //IV
+    }
+
+    @Override
+    public String getNamespace() {
+        return NAMESPACE;
+    }
+}

smack-experimental/src/main/java/org/jivesoftware/smackx/ciphers/AesGcmNoPadding.java

@@ -0,0 +1,105 @@
+/**
+ *
+ * Copyright 2017 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jivesoftware.smackx.ciphers;
+
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.NoSuchProviderException;
+import java.security.SecureRandom;
+import javax.crypto.Cipher;
+import javax.crypto.KeyGenerator;
+import javax.crypto.NoSuchPaddingException;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+
+public abstract class AesGcmNoPadding {
+
+    public static final String keyType = "AES";
+    public static final String cipherMode = "AES/GCM/NoPadding";
+
+    private final int length;
+    protected final Cipher cipher;
+    protected final byte[] key, iv, keyAndIv;
+
+    public AesGcmNoPadding(int length) throws NoSuchAlgorithmException, NoSuchProviderException,
+            NoSuchPaddingException, InvalidAlgorithmParameterException, InvalidKeyException {
+        this.length = length;
+
+        KeyGenerator keyGenerator = KeyGenerator.getInstance(keyType);
+        keyGenerator.init(length);
+        key = keyGenerator.generateKey().getEncoded();
+
+        SecureRandom secureRandom = new SecureRandom();
+        iv = new byte[length];
+        secureRandom.nextBytes(iv);
+
+        keyAndIv = new byte[2 * length];
+        System.arraycopy(key, 0, keyAndIv, 0, length);
+        System.arraycopy(iv, 0, keyAndIv, length, length);
+
+        SecretKey secretKey = new SecretKeySpec(key, keyType);
+        IvParameterSpec ivSpec = new IvParameterSpec(iv);
+        cipher = Cipher.getInstance(cipherMode, "BC");
+        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);
+    }
+
+    public AesGcmNoPadding(byte[] key, byte[] iv) throws NoSuchPaddingException, NoSuchAlgorithmException,
+            NoSuchProviderException, InvalidAlgorithmParameterException, InvalidKeyException {
+        this.length = key.length;
+        this.key = key;
+        this.iv = iv;
+
+        keyAndIv = new byte[2 * length];
+        System.arraycopy(key, 0, keyAndIv, 0, length);
+        System.arraycopy(iv, 0, keyAndIv, length, length);
+
+        cipher = Cipher.getInstance(cipherMode, "BC");
+        SecretKeySpec keySpec = new SecretKeySpec(key, keyType);
+        IvParameterSpec ivSpec = new IvParameterSpec(iv);
+        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
+    }
+
+    public byte[] getKeyAndIv() {
+        return keyAndIv.clone();
+    }
+
+    public byte[] getKey() {
+        return key.clone();
+    }
+
+    public byte[] getIv() {
+        return iv.clone();
+    }
+
+    public int getLength() {
+        return length;
+    }
+
+    public Cipher getCipher() {
+        return cipher;
+    }
+
+    public abstract String getNamespace();
+
+    public static byte[] copyOfRange(byte[] source, int start, int end) {
+        byte[] copy = new byte[end - start];
+        System.arraycopy(source, start, copy, 0, end - start);
+        return copy;
+    }
+}

smack-experimental/src/main/java/org/jivesoftware/smackx/ciphers/package-info.java

@@ -0,0 +1,22 @@
+/**
+ *
+ * Copyright 2017 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Smack's API for XEP-XXXX: Ciphers</a>.
+ * This contains some AES cipher utility functions.
+ */
+package org.jivesoftware.smackx.ciphers;

smack-experimental/src/main/java/org/jivesoftware/smackx/jet/JetManager.java

@@ -20,13 +20,14 @@ import java.io.File;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.WeakHashMap;
-import java.util.logging.Logger;
 
 import org.jivesoftware.smack.Manager;
 import org.jivesoftware.smack.XMPPConnection;
 import org.jivesoftware.smackx.jet.internal.JetSecurity;
+import org.jivesoftware.smackx.jft.JingleFileTransferManager;
 import org.jivesoftware.smackx.jft.controller.OutgoingFileOfferController;
 import org.jivesoftware.smackx.jft.internal.JingleOutgoingFileOffer;
+import org.jivesoftware.smackx.jingle.JingleDescriptionManager;
 import org.jivesoftware.smackx.jingle.JingleManager;
 import org.jivesoftware.smackx.jingle.JingleTransportManager;
 import org.jivesoftware.smackx.jingle.components.JingleContent;
@@ -39,16 +40,17 @@ import org.jxmpp.jid.FullJid;
 /**
  * Manager for Jingle Encrypted Transfers (XEP-XXXX).
  */
-public final class JetManager extends Manager {
+public final class JetManager extends Manager implements JingleDescriptionManager {
-
-    private static final Logger LOGGER = Logger.getLogger(JetManager.class.getName());
 
     private static final WeakHashMap<XMPPConnection, JetManager> INSTANCES = new WeakHashMap<>();
-
     private static final Map<String, JingleEncryptionMethod> encryptionMethods = new HashMap<>();
 
     private final JingleManager jingleManager;
 
+    static {
+        JingleManager.addJingleSecurityAdapter(new JetSecurityAdapter());
+    }
+
     private JetManager(XMPPConnection connection) {
         super(connection);
         this.jingleManager = JingleManager.getInstanceFor(connection);
@@ -65,7 +67,7 @@ public final class JetManager extends Manager {
         return manager;
     }
 
-    public OutgoingFileOfferController sendEncryptedFile(FullJid recipient, File file, String encryptionMethodNamespace) throws Exception {
+    public OutgoingFileOfferController sendEncryptedFile(FullJid recipient, File file, JingleEncryptionMethod method) throws Exception {
         if (file == null || !file.exists()) {
             throw new IllegalArgumentException("File MUST NOT be null and MUST exist.");
         }
@@ -81,16 +83,15 @@ public final class JetManager extends Manager {
         JingleTransportManager transportManager = jingleManager.getBestAvailableTransportManager();
         content.setTransport(transportManager.createTransport(content));
 
-        JetSecurity security = new JetSecurity(encryptionMethodNamespace, connection());
+        JetSecurity security = new JetSecurity(method, recipient, content.getName());
         content.setSecurity(security);
         session.initiate(connection());
 
         return offer;
     }
 
-
+    public void registerEncryptionMethod(JingleEncryptionMethod method) {
-    public void registerEncryptionMethod(String namespace, JingleEncryptionMethod method) {
+        encryptionMethods.put(method.getNamespace(), method);
-        encryptionMethods.put(namespace, method);
     }
 
     public void unregisterEncryptionMethod(String namespace) {
@@ -101,4 +102,18 @@ public final class JetManager extends Manager {
         return encryptionMethods.get(namespace);
     }
 
+    @Override
+    public String getNamespace() {
+        return JetSecurity.NAMESPACE;
+    }
+
+    @Override
+    public void notifySessionInitiate(JingleSession session) {
+        JingleFileTransferManager.getInstanceFor(connection()).notifySessionInitiate(session);
+    }
+
+    @Override
+    public void notifyContentAdd(JingleSession session, JingleContent content) {
+        JingleFileTransferManager.getInstanceFor(connection()).notifyContentAdd(session, content);
+    }
 }

smack-experimental/src/main/java/org/jivesoftware/smackx/jet/JetSecurityAdapter.java

@@ -0,0 +1,35 @@
+/**
+ *
+ * Copyright 2017 Paul Schaub
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.jivesoftware.smackx.jet;
+
+import org.jivesoftware.smackx.jet.element.JetSecurityElement;
+import org.jivesoftware.smackx.jet.internal.JetSecurity;
+import org.jivesoftware.smackx.jingle.adapter.JingleSecurityAdapter;
+import org.jivesoftware.smackx.jingle.element.JingleContentSecurityElement;
+
+public class JetSecurityAdapter implements JingleSecurityAdapter<JetSecurity> {
+
+    @Override
+    public JetSecurity securityFromElement(JingleContentSecurityElement element) {
+        return new JetSecurity((JetSecurityElement) element);
+    }
+
+    @Override
+    public String getNamespace() {
+        return JetSecurity.NAMESPACE;
+    }
+}

smack-experimental/src/main/java/org/jivesoftware/smackx/jet/JingleEncryptionMethod.java

@@ -19,6 +19,7 @@ package org.jivesoftware.smackx.jet;
 import java.security.NoSuchAlgorithmException;
 
 import org.jivesoftware.smack.SmackException;
+import org.jivesoftware.smack.XMPPConnection;
 import org.jivesoftware.smack.XMPPException;
 import org.jivesoftware.smack.packet.ExtensionElement;
 
@@ -40,4 +41,8 @@ public interface JingleEncryptionMethod {
             super(throwable);
         }
     }
+
+    XMPPConnection getConnection();
+
+    String getNamespace();
 }

smack-experimental/src/main/java/org/jivesoftware/smackx/jet/element/JetSecurityElement.java

@@ -57,4 +57,16 @@ public class JetSecurityElement extends JingleContentSecurityElement {
     public String getNamespace() {
         return JetSecurity.NAMESPACE;
     }
+
+    public String getMethodNamespace() {
+        return child.getNamespace();
+    }
+
+    public ExtensionElement getChild() {
+        return child;
+    }
+
+    public String getName() {
+        return name;
+    }
 }

smack-experimental/src/main/java/org/jivesoftware/smackx/jet/internal/JetSecurity.java

@@ -20,18 +20,14 @@ import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
-import java.security.SecureRandom;
-import javax.crypto.Cipher;
-import javax.crypto.KeyGenerator;
 import javax.crypto.NoSuchPaddingException;
-import javax.crypto.SecretKey;
-import javax.crypto.spec.IvParameterSpec;
-import javax.crypto.spec.SecretKeySpec;
 
-import org.jivesoftware.smack.XMPPConnection;
+import org.jivesoftware.smack.SmackException;
+import org.jivesoftware.smack.XMPPException;
 import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smackx.bytestreams.BytestreamSession;
-import org.jivesoftware.smackx.jet.JetManager;
+import org.jivesoftware.smackx.ciphers.Aes256GcmNoPadding;
+import org.jivesoftware.smackx.ciphers.AesGcmNoPadding;
 import org.jivesoftware.smackx.jet.JingleEncryptionMethod;
 import org.jivesoftware.smackx.jet.element.JetSecurityElement;
 import org.jivesoftware.smackx.jingle.callbacks.JingleSecurityCallback;
@@ -39,6 +35,8 @@ import org.jivesoftware.smackx.jingle.components.JingleSecurity;
 import org.jivesoftware.smackx.jingle.element.JingleContentSecurityInfoElement;
 import org.jivesoftware.smackx.jingle.element.JingleElement;
 
+import org.jxmpp.jid.FullJid;
+
 /**
  * Created by vanitas on 22.07.17.
  */
@@ -49,49 +47,35 @@ public class JetSecurity extends JingleSecurity<JetSecurityElement> {
 
     private final String methodNamespace;
 
-    private final Cipher cipher;
+    private AesGcmNoPadding aesKey;
-
     private ExtensionElement child;
+    private String name;
 
-    public JetSecurity(Cipher cipher, ExtensionElement child) {
+    public JetSecurity(JetSecurityElement element) {
         super();
-        this.cipher = cipher;
+        this.child = element.getChild();
-        this.child = child;
+        this.methodNamespace = element.getMethodNamespace();
-        this.methodNamespace = child.getNamespace();
+        this.name = element.getName();
     }
 
-    public JetSecurity(String methodNamespace, XMPPConnection connection)
+    public JetSecurity(JingleEncryptionMethod method, FullJid recipient, String name)
             throws NoSuchAlgorithmException, NoSuchProviderException, NoSuchPaddingException,
-            InvalidAlgorithmParameterException, InvalidKeyException {
+            InvalidAlgorithmParameterException, InvalidKeyException, InterruptedException,
-        this.methodNamespace = methodNamespace;
+            JingleEncryptionMethod.JingleEncryptionException, SmackException.NotConnectedException,
+            SmackException.NoResponseException {
 
-        JetManager jetManager = JetManager.getInstanceFor(connection);
+        this.methodNamespace = method.getNamespace();
-        JingleEncryptionMethod encryptionMethod = jetManager.getEncryptionMethod(methodNamespace);
+        this.aesKey = new Aes256GcmNoPadding();
-        if (encryptionMethod == null) {
+        this.child = method.encryptJingleTransfer(recipient, aesKey.getKeyAndIv());
-            throw new IllegalStateException("No encryption method with namespace " + methodNamespace + " registered.");
+        this.name = name;
     }
 
-        //Create key and cipher
+    public void decryptEncryptionKey(JingleEncryptionMethod method, FullJid sender)
-        int keyLength = 256;
+            throws InterruptedException, JingleEncryptionMethod.JingleEncryptionException, XMPPException.XMPPErrorException,
-        String keyType = "AES";
+            SmackException.NotConnectedException, SmackException.NoResponseException, NoSuchAlgorithmException,
-        String cipherMode = "AES/GCM/NoPadding";
+            InvalidAlgorithmParameterException, NoSuchProviderException, InvalidKeyException, NoSuchPaddingException {
-
+        byte[] keyAndIv = method.decryptJingleTransfer(sender, child);
-        KeyGenerator keyGenerator = KeyGenerator.getInstance(keyType);
+        aesKey = new Aes256GcmNoPadding(keyAndIv);
-        keyGenerator.init(keyLength);
-        byte[] key = keyGenerator.generateKey().getEncoded();
-
-        SecureRandom secureRandom = new SecureRandom();
-        byte[] iv = new byte[keyLength];
-        secureRandom.nextBytes(iv);
-
-        byte[] keyAndIv = new byte[2 * keyLength];
-        System.arraycopy(key, 0, keyAndIv, 0, keyLength);
-        System.arraycopy(iv, 0, keyAndIv, keyLength, keyLength);
-
-        SecretKey secretKey = new SecretKeySpec(key, keyType);
-        IvParameterSpec ivSpec = new IvParameterSpec(iv);
-        cipher = Cipher.getInstance(cipherMode, "BC");
-        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);
     }
 
     @Override
@@ -106,13 +90,20 @@ public class JetSecurity extends JingleSecurity<JetSecurityElement> {
 
     @Override
     public void decryptIncomingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callback) {
-        JetSecurityBytestreamSession securityBytestreamSession = new JetSecurityBytestreamSession(bytestreamSession, cipher);
+        if (aesKey == null) {
+            throw new IllegalStateException("Encryption key has not yet been decrypted.");
+        }
+        JetSecurityBytestreamSession securityBytestreamSession = new JetSecurityBytestreamSession(bytestreamSession, aesKey.getCipher());
         callback.onSecurityReady(securityBytestreamSession);
     }
 
     @Override
-    public void encryptIncomingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callback) {
+    public void encryptOutgoingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callback) {
-        JetSecurityBytestreamSession securityBytestreamSession = new JetSecurityBytestreamSession(bytestreamSession, cipher);
+        JetSecurityBytestreamSession securityBytestreamSession = new JetSecurityBytestreamSession(bytestreamSession, aesKey.getCipher());
         callback.onSecurityReady(securityBytestreamSession);
     }
+
+    public String getMethodNamespace() {
+        return methodNamespace;
+    }
 }

smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/components/JingleContent.java

@@ -102,8 +102,7 @@ public class JingleContent implements JingleTransportCallback, JingleSecurityCal
             if (descriptionAdapter != null) {
                 description = descriptionAdapter.descriptionFromElement(content.getCreator(), content.getSenders(), content.getName(), content.getDisposition(), descriptionElement);
             } else {
-                throw new AssertionError("DescriptionProvider for " + descriptionElement.getNamespace() +
+                throw new AssertionError("Unsupported Description: " + descriptionElement.getNamespace());
-                        " seems to be registered, but no corresponding JingleDescriptionAdapter was found.");
             }
         }
 
@@ -113,8 +112,7 @@ public class JingleContent implements JingleTransportCallback, JingleSecurityCal
             if (transportAdapter != null) {
                 transport = transportAdapter.transportFromElement(transportElement);
             } else {
-                throw new AssertionError("TransportProvider for " + transportElement.getNamespace() +
+                throw new AssertionError("Unsupported Transport: " + transportElement.getNamespace());
-                        " seems to be registered, but no corresponding JingleTransportAdapter was found.");
             }
         }
 
@@ -124,8 +122,7 @@ public class JingleContent implements JingleTransportCallback, JingleSecurityCal
             if (securityAdapter != null) {
                 security = securityAdapter.securityFromElement(securityElement);
             } else {
-                throw new AssertionError("SecurityProvider for " + securityElement.getNamespace() +
+                throw new AssertionError("Unsupported Security: " + securityElement.getNamespace());
-                        " seems to be registered, but no corresponding JingleSecurityAdapter was found.");
             }
         }
 
@@ -341,7 +338,7 @@ public class JingleContent implements JingleTransportCallback, JingleSecurityCal
                 getSecurity().decryptIncomingBytestream(bytestreamSession, this);
             } else if (isSending()) {
                 LOGGER.log(Level.INFO, "Encrypt outgoing Bytestream.");
-                getSecurity().encryptIncomingBytestream(bytestreamSession, this);
+                getSecurity().encryptOutgoingBytestream(bytestreamSession, this);
             }
         } else {
             description.onBytestreamReady(bytestreamSession);

smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/components/JingleSecurity.java

@@ -45,5 +45,5 @@ public abstract class JingleSecurity<D extends JingleContentSecurityElement> {
 
     public abstract void decryptIncomingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callback);
 
-    public abstract void encryptIncomingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callbacks);
+    public abstract void encryptOutgoingBytestream(BytestreamSession bytestreamSession, JingleSecurityCallback callbacks);
 }

smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoManager.java

@@ -799,10 +799,16 @@ public final class OmemoManager extends Manager implements JingleEncryptionMetho
      *
      * @return the connection of this manager
      */
-    XMPPConnection getConnection() {
+    @Override
+    public XMPPConnection getConnection() {
         return connection();
     }
 
+    @Override
+    public String getNamespace() {
+        return OMEMO_NAMESPACE_V_AXOLOTL;
+    }
+
     /**
      * Return the OMEMO service object.
      *