delete secret chat messages as well

This reverts commit 635e5675d1.

build.gradle

@@ -71,6 +71,7 @@ dependencies {
     implementation 'com.google.guava:guava:32.1.3-android'
     implementation 'io.michaelrocks:libphonenumber-android:8.13.17'
     implementation 'im.conversations.webrtc:webrtc-android:119.0.0'
+    implementation 'org.jitsi:org.otr4j:0.23'
 
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     implementation "androidx.recyclerview:recyclerview:1.2.1"
@@ -83,6 +84,7 @@ dependencies {
 
     implementation 'com.github.singpolyma:TokenAutoComplete:bfa93780e0'
 
+    implementation 'com.github.kizitonwose.colorpreference:core:1.1.0'
     implementation 'com.github.kizitonwose.colorpreference:support:1.1.0'
     implementation 'com.caverock:androidsvg-aar:1.4'
     implementation 'com.github.singpolyma:Better-Link-Movement-Method:4df081e1e4'
@@ -102,8 +104,8 @@ android {
     defaultConfig {
         minSdkVersion 24
         targetSdkVersion 34
-        versionCode 42115
-        versionName "2.3.1"
+        versionCode 42116
+        versionName "2.3.2"
         archivesBaseName += "-$versionName"
         applicationId "eu.siacs.conversations.classic"
         resValue "string", "applicationId", applicationId

src/conversations/java/eu/siacs/conversations/ui/ManageAccountActivity.java

@@ -36,6 +36,7 @@ import eu.siacs.conversations.services.XmppConnectionService;
 import eu.siacs.conversations.services.XmppConnectionService.OnAccountUpdate;
 import eu.siacs.conversations.ui.adapter.AccountAdapter;
 import eu.siacs.conversations.ui.util.MenuDoubleTabUtil;
+import eu.siacs.conversations.utils.UIHelper;
 import eu.siacs.conversations.xmpp.Jid;
 import eu.siacs.conversations.xmpp.XmppConnection;
 
@@ -44,8 +45,14 @@ import static eu.siacs.conversations.utils.PermissionUtils.writeGranted;
 
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 import com.google.android.material.navigation.NavigationBarView;
+import com.kizitonwose.colorpreference.ColorDialog;
+import com.kizitonwose.colorpreference.ColorShape;
 
-public class ManageAccountActivity extends XmppActivity implements OnAccountUpdate, KeyChainAliasCallback, XmppConnectionService.OnAccountCreated, AccountAdapter.OnTglAccountState {
+public class ManageAccountActivity extends XmppActivity implements OnAccountUpdate,
+        KeyChainAliasCallback,
+        XmppConnectionService.OnAccountCreated,
+        AccountAdapter.OnTglAccountState,
+        ColorDialog.OnColorSelectedListener {
 
     private final String STATE_SELECTED_ACCOUNT = "selected_account";
 
@@ -61,6 +68,18 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
 
     protected Pair<Integer, Intent> mPostponedActivityResult = null;
 
+    private AccountAdapter.ColorSelectorListener colorSelectorListener = new AccountAdapter.ColorSelectorListener() {
+        @Override
+        public void onColorPickerRequested(Jid accountJid, int currentColor) {
+            new ColorDialog.Builder(ManageAccountActivity.this)
+                    .setColorShape(ColorShape.CIRCLE)
+                    .setColorChoices(R.array.themeColorsOverride)
+                    .setSelectedColor(currentColor)
+                    .setTag(accountJid.asBareJid().toEscapedString())
+                    .show();
+        }
+    };
+
     @Override
     public void onAccountUpdate() {
         refreshUi();
@@ -102,7 +121,7 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
         }
 
         accountListView = findViewById(R.id.account_list);
-        this.mAccountAdapter = new AccountAdapter(this, accountList);
+        this.mAccountAdapter = new AccountAdapter(this, accountList, colorSelectorListener);
         accountListView.setAdapter(this.mAccountAdapter);
         accountListView.setOnItemClickListener((arg0, view, position, arg3) -> switchToAccount(accountList.get(position)));
         registerForContextMenu(accountListView);
@@ -158,6 +177,13 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
         super.onSaveInstanceState(savedInstanceState);
     }
 
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        colorSelectorListener = null;
+        mAccountAdapter.colorSelectorListener = null;
+    }
+
     @Override
     public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
         super.onCreateContextMenu(menu, v, menuInfo);
@@ -349,6 +375,12 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
         }
     }
 
+    @Override
+    public void onColorSelected(int newColor, String tag) {
+        UIHelper.overrideAccountColor(this, tag, newColor);
+        refreshUiReal();
+    }
+
     private void addAccountFromKey() {
         try {
             KeyChain.choosePrivateKeyAlias(this, this, null, null, null, -1, null);

src/main/AndroidManifest.xml

@@ -299,6 +299,11 @@
         <activity
             android:name=".ui.PublishGroupChatProfilePictureActivity"
             android:label="@string/group_chat_avatar" />
+        <activity
+            android:name=".ui.VerifyOTRActivity"
+            android:label="@string/verify_otr"
+            android:exported="false"
+            android:windowSoftInputMode="stateHidden" />
         <activity
             android:name=".ui.ShareWithActivity"
             android:exported="true"

src/main/java/eu/siacs/conversations/Config.java

@@ -15,9 +15,10 @@ import eu.siacs.conversations.xmpp.chatstate.ChatState;
 public final class Config {
     private static final int UNENCRYPTED = 1;
     private static final int OPENPGP = 2;
+    private static final int OTR = 4;
     private static final int OMEMO = 8;
 
-    private static final int ENCRYPTION_MASK = UNENCRYPTED | OPENPGP | OMEMO;
+    private static final int ENCRYPTION_MASK = UNENCRYPTED | OPENPGP | OTR | OMEMO;
 
     public static boolean supportUnencrypted() {
         return (ENCRYPTION_MASK & UNENCRYPTED) != 0;
@@ -31,6 +32,10 @@ public final class Config {
         return (ENCRYPTION_MASK & OMEMO) != 0;
     }
 
+    public static boolean supportOtr() {
+        return (ENCRYPTION_MASK & OTR) != 0;
+    }
+
     public static boolean omemoOnly() {
         return !multipleEncryptionChoices() && supportOmemo();
     }

src/main/java/eu/siacs/conversations/crypto/OtrService.java

@@ -0,0 +1,312 @@
+package eu.siacs.conversations.crypto;
+
+import android.util.Log;
+
+import net.java.otr4j.OtrEngineHost;
+import net.java.otr4j.OtrException;
+import net.java.otr4j.OtrPolicy;
+import net.java.otr4j.OtrPolicyImpl;
+import net.java.otr4j.crypto.OtrCryptoEngineImpl;
+import net.java.otr4j.crypto.OtrCryptoException;
+import net.java.otr4j.session.FragmenterInstructions;
+import net.java.otr4j.session.InstanceTag;
+import net.java.otr4j.session.SessionID;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+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 eu.siacs.conversations.Config;
+import eu.siacs.conversations.entities.Account;
+import eu.siacs.conversations.entities.Conversation;
+import eu.siacs.conversations.generator.MessageGenerator;
+import eu.siacs.conversations.services.XmppConnectionService;
+import eu.siacs.conversations.xmpp.Jid;
+import eu.siacs.conversations.xmpp.chatstate.ChatState;
+import eu.siacs.conversations.xmpp.jid.OtrJidHelper;
+import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
+
+public class OtrService extends OtrCryptoEngineImpl implements OtrEngineHost {
+
+    private Account account;
+    private OtrPolicy otrPolicy;
+    private KeyPair keyPair;
+    private XmppConnectionService mXmppConnectionService;
+
+    public OtrService(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(final JSONObject keys) {
+        if (keys == null) {
+            return null;
+        }
+        synchronized (keys) {
+            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 (final NoSuchAlgorithmException e) {
+            e.printStackTrace();
+        } catch (final InvalidKeySpecException e) {
+            e.printStackTrace();
+        }
+
+    }
+
+    @Override
+    public void askForSecret(SessionID id, InstanceTag instanceTag, String question) {
+        try {
+            final Jid jid = OtrJidHelper.fromSessionID(id);
+            Conversation conversation = this.mXmppConnectionService.find(this.account, jid, jid);
+            if (conversation != null) {
+                conversation.smp().hint = question;
+                conversation.smp().status = Conversation.Smp.STATUS_CONTACT_REQUESTED;
+                mXmppConnectionService.updateConversationUi();
+            }
+        } catch (IllegalArgumentException e) {
+            Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": smp in invalid session " + id.toString());
+        }
+    }
+
+    @Override
+    public void finishedSessionMessage(SessionID arg0, String arg1)
+            throws OtrException {
+
+    }
+
+    @Override
+    public String getFallbackMessage(SessionID arg0) {
+        return MessageGenerator.OTR_FALLBACK_MESSAGE;
+    }
+
+    @Override
+    public byte[] getLocalFingerprintRaw(SessionID arg0) {
+        try {
+            return getFingerprintRaw(getPublicKey());
+        } catch (OtrCryptoException e) {
+            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.getJid());
+        if (session.getUserID().isEmpty()) {
+            packet.setAttribute("to", session.getAccountID());
+        } else {
+            packet.setAttribute("to", session.getAccountID() + "/" + session.getUserID());
+        }
+        packet.setBody(body);
+        MessageGenerator.addMessageHints(packet);
+        try {
+            Jid jid = OtrJidHelper.fromSessionID(session);
+            Conversation conversation = mXmppConnectionService.find(account, jid, jid);
+            if (conversation != null && conversation.setOutgoingChatState(Config.DEFAULT_CHAT_STATE)) {
+                if (mXmppConnectionService.sendChatStates()) {
+                    packet.addChild(ChatState.toElement(conversation.getOutgoingChatState()));
+                }
+            }
+        } catch (final IllegalArgumentException ignored) {
+
+        }
+
+        packet.setType(MessagePacket.TYPE_CHAT);
+        packet.addChild("encryption", "urn:xmpp:eme:0").setAttribute("namespace", "urn:xmpp:otr:0");
+        account.getXmppConnection().sendMessagePacket(packet);
+    }
+
+    @Override
+    public void messageFromAnotherInstanceReceived(SessionID session) {
+        sendOtrErrorMessage(session, "Message from another OTR-instance received");
+    }
+
+    @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 {
+        Log.d(Config.LOGTAG, "show error");
+    }
+
+    @Override
+    public void smpAborted(SessionID id) throws OtrException {
+        setSmpStatus(id, Conversation.Smp.STATUS_NONE);
+    }
+
+    private void setSmpStatus(SessionID id, int status) {
+        try {
+            final Jid jid = OtrJidHelper.fromSessionID(id);
+            Conversation conversation = this.mXmppConnectionService.find(this.account, jid, jid);
+            if (conversation != null) {
+                conversation.smp().status = status;
+                mXmppConnectionService.updateConversationUi();
+            }
+        } catch (final IllegalArgumentException ignored) {
+
+        }
+    }
+
+    @Override
+    public void smpError(SessionID id, int arg1, boolean arg2)
+            throws OtrException {
+        setSmpStatus(id, Conversation.Smp.STATUS_NONE);
+    }
+
+    @Override
+    public void unencryptedMessageReceived(SessionID arg0, String arg1)
+            throws OtrException {
+        throw new OtrException(new Exception("unencrypted message received"));
+    }
+
+    @Override
+    public void unreadableMessageReceived(SessionID session) throws OtrException {
+        Log.d(Config.LOGTAG, "unreadable message received");
+        sendOtrErrorMessage(session, "You sent me an unreadable OTR-encrypted message");
+    }
+
+    public void sendOtrErrorMessage(SessionID session, String errorText) {
+        try {
+            Jid jid = OtrJidHelper.fromSessionID(session);
+            Conversation conversation = mXmppConnectionService.find(account, jid, jid);
+            String id = conversation == null ? null : conversation.getLastReceivedOtrMessageId();
+            if (id != null) {
+                MessagePacket packet = mXmppConnectionService.getMessageGenerator()
+                        .generateOtrError(jid, id, errorText);
+                packet.setFrom(account.getJid());
+                mXmppConnectionService.sendMessagePacket(account, packet);
+                Log.d(Config.LOGTAG, packet.toString());
+                Log.d(Config.LOGTAG, account.getJid().asBareJid().toString()
+                        + ": unreadable OTR message in " + conversation.getName());
+            }
+        } catch (IllegalArgumentException e) {
+            return;
+        }
+    }
+
+    @Override
+    public void unverify(SessionID id, String arg1) {
+        setSmpStatus(id, Conversation.Smp.STATUS_FAILED);
+    }
+
+    @Override
+    public void verify(SessionID id, String fingerprint, boolean approved) {
+        Log.d(Config.LOGTAG, "OtrService.verify(" + id.toString() + "," + fingerprint + "," + String.valueOf(approved) + ")");
+        try {
+            final Jid jid = OtrJidHelper.fromSessionID(id);
+            Conversation conversation = this.mXmppConnectionService.find(this.account, jid, jid);
+            if (conversation != null) {
+                if (approved) {
+                    conversation.getContact().addOtrFingerprint(fingerprint);
+                }
+                conversation.smp().hint = null;
+                conversation.smp().status = Conversation.Smp.STATUS_VERIFIED;
+                mXmppConnectionService.updateConversationUi();
+                mXmppConnectionService.syncRosterToDisk(conversation.getAccount());
+            }
+        } catch (final IllegalArgumentException ignored) {
+        }
+    }
+
+    @Override
+    public FragmenterInstructions getFragmenterInstructions(SessionID sessionID) {
+        return null;
+    }
+
+}

src/main/java/eu/siacs/conversations/entities/Account.java

@@ -8,20 +8,27 @@ import android.util.Log;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 
+import net.java.otr4j.crypto.OtrCryptoEngineImpl;
+import net.java.otr4j.crypto.OtrCryptoException;
+
 import org.json.JSONException;
 import org.json.JSONObject;
 
+import java.security.PublicKey;
+import java.security.interfaces.DSAPublicKey;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.R;
+import eu.siacs.conversations.crypto.OtrService;
 import eu.siacs.conversations.crypto.PgpDecryptionService;
 import eu.siacs.conversations.crypto.axolotl.AxolotlService;
 import eu.siacs.conversations.crypto.axolotl.XmppAxolotlSession;
@@ -93,6 +100,7 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
     protected String avatar;
     protected String hostname = null;
     protected int port = 5222;
+    private OtrService mOtrService = null;
     protected boolean online = false;
     private String rosterVersion;
     private String displayName = null;
@@ -100,6 +108,7 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
     private PgpDecryptionService pgpDecryptionService = null;
     private XmppConnection xmppConnection = null;
     private long mEndGracePeriod = 0L;
+    private String otrFingerprint;
     private final Map<Jid, Bookmark> bookmarks = new HashMap<>();
     private Presence.Status presenceStatus;
     private String presenceStatusMessage;
@@ -535,6 +544,7 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
     }
 
     public void initAccountServices(final XmppConnectionService context) {
+        this.mOtrService = new OtrService(context, this);
         this.axolotlService = new AxolotlService(this, context);
         this.pgpDecryptionService = new PgpDecryptionService(context);
         if (xmppConnection != null) {
@@ -542,6 +552,10 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
         }
     }
 
+    public OtrService getOtrService() {
+        return this.mOtrService;
+    }
+
     public PgpDecryptionService getPgpDecryptionService() {
         return this.pgpDecryptionService;
     }
@@ -554,6 +568,27 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
         this.xmppConnection = connection;
     }
 
+    public String getOtrFingerprint() {
+        if (this.otrFingerprint == null) {
+            try {
+                if (this.mOtrService == null) {
+                    return null;
+                }
+                final PublicKey publicKey = this.mOtrService.getPublicKey();
+                if (publicKey == null || !(publicKey instanceof DSAPublicKey)) {
+                    return null;
+                }
+                this.otrFingerprint = new OtrCryptoEngineImpl().getFingerprint(publicKey).toLowerCase(Locale.US);
+                return this.otrFingerprint;
+            } catch (final OtrCryptoException ignored) {
+                return null;
+            }
+        } else {
+            return this.otrFingerprint;
+        }
+    }
+
+
     public String getRosterVersion() {
         if (this.rosterVersion == null) {
             return "";
@@ -721,6 +756,10 @@ public class Account extends AbstractEntity implements AvatarService.Avatarable
 
     private List<XmppUri.Fingerprint> getFingerprints() {
         ArrayList<XmppUri.Fingerprint> fingerprints = new ArrayList<>();
+        final String otr = this.getOtrFingerprint();
+        if (otr != null) {
+            fingerprints.add(new XmppUri.Fingerprint(XmppUri.FingerprintType.OTR, otr));
+        }
         if (axolotlService == null) {
             return fingerprints;
         }

src/main/java/eu/siacs/conversations/entities/Contact.java

@@ -348,6 +348,47 @@ public class Contact implements ListItem, Blockable {
         return groups;
     }
 
+    public ArrayList<String> getOtrFingerprints() {
+        synchronized (this.keys) {
+            final ArrayList<String> fingerprints = new ArrayList<String>();
+            try {
+                if (this.keys.has("otr_fingerprints")) {
+                    final JSONArray prints = this.keys.getJSONArray("otr_fingerprints");
+                    for (int i = 0; i < prints.length(); ++i) {
+                        final String print = prints.isNull(i) ? null : prints.getString(i);
+                        if (print != null && !print.isEmpty()) {
+                            fingerprints.add(prints.getString(i).toLowerCase(Locale.US));
+                        }
+                    }
+                }
+            } catch (final JSONException ignored) {
+
+            }
+            return fingerprints;
+        }
+    }
+
+    public boolean addOtrFingerprint(String print) {
+        synchronized (this.keys) {
+            if (getOtrFingerprints().contains(print)) {
+                return false;
+            }
+            try {
+                JSONArray fingerprints;
+                if (!this.keys.has("otr_fingerprints")) {
+                    fingerprints = new JSONArray();
+                } else {
+                    fingerprints = this.keys.getJSONArray("otr_fingerprints");
+                }
+                fingerprints.put(print);
+                this.keys.put("otr_fingerprints", fingerprints);
+                return true;
+            } catch (final JSONException ignored) {
+                return false;
+            }
+        }
+    }
+
     public long getPgpKeyId() {
         synchronized (this.keys) {
             if (this.keys.has("pgp_keyid")) {

src/main/java/eu/siacs/conversations/entities/Conversation.java

@@ -71,6 +71,7 @@ import org.json.JSONException;
 import org.json.JSONObject;
 
 import java.lang.ref.WeakReference;
+import java.security.interfaces.DSAPublicKey;
 import java.time.ZoneId;
 import java.time.ZonedDateTime;
 import java.time.format.DateTimeFormatter;
@@ -81,6 +82,7 @@ import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.ListIterator;
+import java.util.Locale;
 import java.util.Objects;
 import java.util.Set;
 import java.util.Timer;
@@ -132,6 +134,12 @@ import me.saket.bettermovementmethod.BetterLinkMovementMethod;
 
 import static eu.siacs.conversations.entities.Bookmark.printableValue;
 
+import net.java.otr4j.OtrException;
+import net.java.otr4j.crypto.OtrCryptoException;
+import net.java.otr4j.session.SessionID;
+import net.java.otr4j.session.SessionImpl;
+import net.java.otr4j.session.SessionStatus;
+
 
 public class Conversation extends AbstractEntity implements Blockable, Comparable<Conversation>, Conversational, AvatarService.Avatarable {
     public static final String TABLENAME = "conversations";
@@ -180,10 +188,16 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
     private int mode;
     private JSONObject attributes;
     private Jid nextCounterpart;
+    private boolean hasPermanentCounterpart;
+    private transient SessionImpl otrSession;
+    private transient String otrFingerprint = null;
+    private Smp mSmp = new Smp();
     private transient MucOptions mucOptions = null;
+    private byte[] symmetricKey;
     private boolean messagesLeftOnServer = true;
     private ChatState mOutgoingChatState = Config.DEFAULT_CHAT_STATE;
     private ChatState mIncomingChatState = Config.DEFAULT_CHAT_STATE;
+    private String mLastReceivedOtrMessageId = null;
     private String mFirstMamReference = null;
     protected Message replyTo = null;
     protected int mCurrentTab = -1;
@@ -216,6 +230,9 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
             this.attributes = new JSONObject();
         }
         this.nextCounterpart = nextCounterpart;
+        if (nextCounterpart != null) {
+            hasPermanentCounterpart = true;
+        }
     }
 
     public String getContactUuid() {
@@ -490,6 +507,17 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         }
     }
 
+    public void findUnsentMessagesWithEncryption(int encryptionType, OnMessageFound onMessageFound) {
+        synchronized (this.messages) {
+            for (Message message : this.messages) {
+                if ((message.getStatus() == Message.STATUS_UNSEND || message.getStatus() == Message.STATUS_WAITING)
+                        && (message.getEncryption() == encryptionType)) {
+                    onMessageFound.onMessageFound(message);
+                }
+            }
+        }
+    }
+
     public void findUnsentTextMessages(OnMessageFound onMessageFound) {
         final ArrayList<Message> results = new ArrayList<>();
         synchronized (this.messages) {
@@ -662,6 +690,14 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         return getContact().getBlockedJid();
     }
 
+    public String getLastReceivedOtrMessageId() {
+        return this.mLastReceivedOtrMessageId;
+    }
+
+    public void setLastReceivedOtrMessageId(String id) {
+        this.mLastReceivedOtrMessageId = id;
+    }
+
     public int countMessages() {
         synchronized (this.messages) {
             return this.messages.size();
@@ -905,7 +941,7 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         values.put(STATUS, status);
         values.put(MODE, mode);
 
-        if (nextCounterpart != null) {
+        if (nextCounterpart != null && hasPermanentCounterpart) {
             values.put(NEXT_COUNTERPART, nextCounterpart.toString());
         }
 
@@ -923,6 +959,124 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         this.mode = mode;
     }
 
+    public SessionImpl startOtrSession(String presence, boolean sendStart) {
+        if (this.otrSession != null) {
+            return this.otrSession;
+        } else {
+            final SessionID sessionId = new SessionID(this.getJid().asBareJid().toString(),
+                    presence,
+                    "xmpp");
+            this.otrSession = new SessionImpl(sessionId, getAccount().getOtrService());
+            try {
+                if (sendStart) {
+                    this.otrSession.startSession();
+                    return this.otrSession;
+                }
+                return this.otrSession;
+            } catch (OtrException e) {
+                return null;
+            }
+        }
+
+    }
+
+    public SessionImpl getOtrSession() {
+        return this.otrSession;
+    }
+
+    public void resetOtrSession() {
+        this.otrFingerprint = null;
+        this.otrSession = null;
+        this.mSmp.hint = null;
+        this.mSmp.secret = null;
+        this.mSmp.status = Smp.STATUS_NONE;
+    }
+
+    public Smp smp() {
+        return mSmp;
+    }
+
+    public boolean startOtrIfNeeded() {
+        if (this.otrSession != null && this.otrSession.getSessionStatus() != SessionStatus.ENCRYPTED) {
+            try {
+                this.otrSession.startSession();
+                return true;
+            } catch (OtrException e) {
+                this.resetOtrSession();
+                return false;
+            }
+        } else {
+            return true;
+        }
+    }
+
+    public boolean endOtrIfNeeded() {
+        if (this.otrSession != null) {
+            if (this.otrSession.getSessionStatus() == SessionStatus.ENCRYPTED) {
+                try {
+                    this.otrSession.endSession();
+                    this.resetOtrSession();
+                    return true;
+                } catch (OtrException e) {
+                    this.resetOtrSession();
+                    return false;
+                }
+            } else {
+                this.resetOtrSession();
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    public boolean hasValidOtrSession() {
+        return this.otrSession != null;
+    }
+
+    public synchronized String getOtrFingerprint() {
+        if (this.otrFingerprint == null) {
+            try {
+                if (getOtrSession() == null || getOtrSession().getSessionStatus() != SessionStatus.ENCRYPTED) {
+                    return null;
+                }
+                DSAPublicKey remotePubKey = (DSAPublicKey) getOtrSession().getRemotePublicKey();
+                this.otrFingerprint = getAccount().getOtrService().getFingerprint(remotePubKey).toLowerCase(Locale.US);
+            } catch (final OtrCryptoException ignored) {
+                return null;
+            } catch (final UnsupportedOperationException ignored) {
+                return null;
+            }
+        }
+        return this.otrFingerprint;
+    }
+
+    public boolean verifyOtrFingerprint() {
+        final String fingerprint = getOtrFingerprint();
+        if (fingerprint != null) {
+            getContact().addOtrFingerprint(fingerprint);
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    public boolean isOtrFingerprintVerified() {
+        return getContact().getOtrFingerprints().contains(getOtrFingerprint());
+    }
+
+    public class Smp {
+        public static final int STATUS_NONE = 0;
+        public static final int STATUS_CONTACT_REQUESTED = 1;
+        public static final int STATUS_WE_REQUESTED = 2;
+        public static final int STATUS_FAILED = 3;
+        public static final int STATUS_VERIFIED = 4;
+
+        public String secret = null;
+        public String hint = null;
+        public int status = 0;
+    }
+
     /**
      * short for is Private and Non-anonymous
      */
@@ -959,14 +1113,23 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         return this.nextCounterpart;
     }
 
+    public boolean hasPermanentCounterpart() {
+        return hasPermanentCounterpart;
+    }
+
     public void setNextCounterpart(Jid jid) {
         this.nextCounterpart = jid;
     }
 
     public int getNextEncryption() {
-        if (!Config.supportOmemo() && !Config.supportOpenPgp()) {
+        if (!Config.supportOmemo() && !Config.supportOpenPgp() && !Config.supportOtr()) {
             return Message.ENCRYPTION_NONE;
         }
+
+        if (Config.supportOtr() && nextCounterpart != null && getMode() == MODE_SINGLE && hasPermanentCounterpart) {
+            return Message.ENCRYPTION_OTR;
+        }
+
         if (OmemoSetting.isAlways()) {
             return suitableForOmemoByDefault(this) ? Message.ENCRYPTION_AXOLOTL : Message.ENCRYPTION_NONE;
         }
@@ -977,7 +1140,7 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
             defaultEncryption = Message.ENCRYPTION_NONE;
         }
         int encryption = this.getIntAttribute(ATTRIBUTE_NEXT_ENCRYPTION, defaultEncryption);
-        if (encryption == Message.ENCRYPTION_OTR || encryption < 0) {
+        if (encryption < 0) {
             return defaultEncryption;
         } else {
             return encryption;
@@ -993,6 +1156,10 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         return nextMessage == null ? "" : nextMessage;
     }
 
+    public boolean smpRequested() {
+        return smp().status == Smp.STATUS_CONTACT_REQUESTED;
+    }
+
     public @Nullable
     Draft getDraft() {
         long timestamp = getLongAttribute(ATTRIBUTE_NEXT_MESSAGE_TIMESTAMP, 0);
@@ -1015,6 +1182,14 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         return changed;
     }
 
+    public void setSymmetricKey(byte[] key) {
+        this.symmetricKey = key;
+    }
+
+    public byte[] getSymmetricKey() {
+        return this.symmetricKey;
+    }
+
     public Bookmark getBookmark() {
         return this.account.getBookmark(this.contactJid);
     }
@@ -1231,14 +1406,14 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         String res2 = nextCounterpart == null ? null : nextCounterpart.getResource();
 
         if (nextCounterpart == null) {
-            if (!message.isPrivateMessage()) {
+            if (!message.isPrivateMessage() && message.encryption != Message.ENCRYPTION_OTR) {
                 synchronized (this.messages) {
                     this.messages.add(message);
                     actualizeReplyMessages(this.messages, List.of(message));
                 }
             }
         } else {
-            if (message.isPrivateMessage() && Objects.equals(res1, res2)) {
+            if ((message.isPrivateMessage() || message.encryption == Message.ENCRYPTION_OTR) && Objects.equals(res1, res2)) {
                 synchronized (this.messages) {
                     this.messages.add(message);
                     actualizeReplyMessages(this.messages, List.of(message));
@@ -1260,14 +1435,14 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
         }
 
         if (nextCounterpart == null) {
-            if (!message.isPrivateMessage()) {
+            if (!message.isPrivateMessage() && message.encryption != Message.ENCRYPTION_OTR) {
                 synchronized (this.messages) {
                     properListToAdd.add(Math.min(offset, properListToAdd.size()), message);
                     actualizeReplyMessages(properListToAdd, List.of(message));
                 }
             }
         } else {
-            if (message.isPrivateMessage() && Objects.equals(res1, res2)) {
+            if ((message.isPrivateMessage() || message.encryption == Message.ENCRYPTION_OTR) && Objects.equals(res1, res2)) {
                 synchronized (this.messages) {
                     properListToAdd.add(Math.min(offset, properListToAdd.size()), message);
                     actualizeReplyMessages(properListToAdd, List.of(message));
@@ -1291,7 +1466,7 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
 
         if (nextCounterpart == null) {
             for(Message m : messages) {
-                if (!m.isPrivateMessage()) {
+                if (!m.isPrivateMessage() && m.encryption != Message.ENCRYPTION_OTR) {
                     newM.add(m);
                 }
             }
@@ -1302,7 +1477,7 @@ public class Conversation extends AbstractEntity implements Blockable, Comparabl
                 String res2 = nextCounterpart == null ? null : nextCounterpart.getResource();
 
 
-                if (m.isPrivateMessage() && Objects.equals(res1, res2)) {
+                if ((m.isPrivateMessage() || m.encryption == Message.ENCRYPTION_OTR) && Objects.equals(res1, res2)) {
                     newM.add(m);
                 }
             }

src/main/java/eu/siacs/conversations/entities/Message.java

@@ -352,7 +352,10 @@ public class Message extends AbstractEntity implements AvatarService.Avatarable
     }
 
     public String replyId() {
-        return conversation.getMode() == Conversation.MODE_MULTI || getRemoteMsgId() == null ? getServerMsgId() : getRemoteMsgId();
+        if (conversation.getMode() == Conversation.MODE_MULTI) return getServerMsgId();
+        final String remote = getRemoteMsgId();
+        if (remote == null && getStatus() > STATUS_RECEIVED) return getUuid();
+        return remote;
     }
 
     public Message reply() {

src/main/java/eu/siacs/conversations/entities/Transferable.java

@@ -6,7 +6,7 @@ import java.util.List;
 public interface Transferable {
 
 	List<String> VALID_IMAGE_EXTENSIONS = Arrays.asList("webp", "jpeg", "jpg", "png", "jpe");
-	List<String> VALID_CRYPTO_EXTENSIONS = Arrays.asList("pgp", "gpg");
+	List<String> VALID_CRYPTO_EXTENSIONS = Arrays.asList("pgp", "gpg", "otr");
 
 	int STATUS_UNKNOWN = 0x200;
 	int STATUS_CHECKING = 0x201;

src/main/java/eu/siacs/conversations/generator/AbstractGenerator.java

@@ -57,6 +57,9 @@ public abstract class AbstractGenerator {
     private final String[] PRIVACY_SENSITIVE = {
             "urn:xmpp:time" //XEP-0202: Entity Time leaks time zone
     };
+    private final String[] OTR = {
+            "urn:xmpp:otr:0"
+    };
     private final String[] VOIP_NAMESPACES = {
             Namespace.JINGLE_TRANSPORT_ICE_UDP,
             Namespace.JINGLE_FEATURE_AUDIO,
@@ -125,6 +128,9 @@ public abstract class AbstractGenerator {
             features.addAll(Arrays.asList(PRIVACY_SENSITIVE));
             features.addAll(Arrays.asList(VOIP_NAMESPACES));
         }
+        if (Config.supportOtr()) {
+            features.addAll(Arrays.asList(OTR));
+        }
         if (mXmppConnectionService.broadcastLastActivity()) {
             features.add(Namespace.IDLE);
         }

src/main/java/eu/siacs/conversations/generator/MessageGenerator.java

@@ -1,5 +1,8 @@
 package eu.siacs.conversations.generator;
 
+import net.java.otr4j.OtrException;
+import net.java.otr4j.session.Session;
+
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Date;
@@ -24,6 +27,7 @@ import eu.siacs.conversations.xmpp.jingle.Media;
 import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
 
 public class MessageGenerator extends AbstractGenerator {
+    public static final String OTR_FALLBACK_MESSAGE = "I would like to start a private (OTR encrypted) conversation but your client doesn’t seem to support that";
     private static final String OMEMO_FALLBACK_MESSAGE = "I sent you an OMEMO encrypted message but your client doesn’t seem to support that. Find more information on https://conversations.im/omemo";
     private static final String PGP_FALLBACK_MESSAGE = "I sent you a PGP encrypted message but your client doesn’t seem to support that.";
 
@@ -102,6 +106,36 @@ public class MessageGenerator extends AbstractGenerator {
         return packet;
     }
 
+    public static void addMessageHints(MessagePacket packet) {
+        packet.addChild("private", "urn:xmpp:carbons:2");
+        packet.addChild("no-copy", "urn:xmpp:hints");
+        packet.addChild("no-permanent-store", "urn:xmpp:hints");
+        packet.addChild("no-permanent-storage", "urn:xmpp:hints"); //do not copy this. this is wrong. it is *store*
+    }
+
+    public MessagePacket generateOtrChat(Message message) {
+        Conversation conversation = (Conversation) message.getConversation();
+        Session otrSession = conversation.getOtrSession();
+        if (otrSession == null) {
+            return null;
+        }
+        MessagePacket packet = preparePacket(message);
+        addMessageHints(packet);
+        try {
+            String content;
+            if (message.hasFileOnRemoteHost()) {
+                content = message.getFileParams().url.toString();
+            } else {
+                content = message.getBody();
+            }
+            packet.setBody(otrSession.transformSending(content)[0]);
+            packet.addChild("encryption", "urn:xmpp:eme:0").setAttribute("namespace", "urn:xmpp:otr:0");
+            return packet;
+        } catch (OtrException e) {
+            return null;
+        }
+    }
+
     public MessagePacket generateChat(Message message) {
         MessagePacket packet = preparePacket(message);
         String content;
@@ -233,6 +267,19 @@ public class MessageGenerator extends AbstractGenerator {
         return packet;
     }
 
+    public MessagePacket generateOtrError(Jid to, String id, String errorText) {
+        MessagePacket packet = new MessagePacket();
+        packet.setType(MessagePacket.TYPE_ERROR);
+        packet.setAttribute("id", id);
+        packet.setTo(to);
+        Element error = packet.addChild("error");
+        error.setAttribute("code", "406");
+        error.setAttribute("type", "modify");
+        error.addChild("not-acceptable", "urn:ietf:params:xml:ns:xmpp-stanzas");
+        error.addChild("text").setContent("?OTR Error:" + errorText);
+        return packet;
+    }
+
     public MessagePacket sessionProposal(final JingleConnectionManager.RtpSessionProposal proposal) {
         final MessagePacket packet = new MessagePacket();
         packet.setType(MessagePacket.TYPE_CHAT); //we want to carbon copy those

src/main/java/eu/siacs/conversations/parser/MessageParser.java

@@ -1,8 +1,15 @@
 package eu.siacs.conversations.parser;
 
+import android.os.Build;
+import android.text.Html;
 import android.util.Log;
 import android.util.Pair;
 
+import com.google.common.base.Strings;
+
+import net.java.otr4j.session.Session;
+import net.java.otr4j.session.SessionStatus;
+
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -16,6 +23,7 @@ import java.util.UUID;
 
 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.R;
+import eu.siacs.conversations.crypto.OtrService;
 import eu.siacs.conversations.crypto.axolotl.AxolotlService;
 import eu.siacs.conversations.crypto.axolotl.BrokenSessionException;
 import eu.siacs.conversations.crypto.axolotl.NotEncryptedForThisDeviceException;
@@ -28,9 +36,11 @@ import eu.siacs.conversations.entities.Conversation;
 import eu.siacs.conversations.entities.Conversational;
 import eu.siacs.conversations.entities.Message;
 import eu.siacs.conversations.entities.MucOptions;
+import eu.siacs.conversations.entities.Presence;
 import eu.siacs.conversations.entities.ReadByMarker;
 import eu.siacs.conversations.entities.ReceiptRequest;
 import eu.siacs.conversations.entities.RtpSessionStatus;
+import eu.siacs.conversations.entities.ServiceDiscoveryResult;
 import eu.siacs.conversations.http.HttpConnectionManager;
 import eu.siacs.conversations.services.MessageArchiveService;
 import eu.siacs.conversations.services.QuickConversationsService;
@@ -49,6 +59,7 @@ import eu.siacs.conversations.xmpp.pep.Avatar;
 import eu.siacs.conversations.xmpp.stanzas.MessagePacket;
 
 public class MessageParser extends AbstractParser implements OnMessagePacketReceived {
+    private static final List<String> CLIENTS_SENDING_HTML_IN_OTR = Arrays.asList("Pidgin", "Adium", "Trillian");
 
     private static final SimpleDateFormat TIME_FORMAT = new SimpleDateFormat("HH:mm:ss", Locale.ENGLISH);
 
@@ -95,6 +106,30 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
         return result != null ? result : fallback;
     }
 
+    private static boolean clientMightSendHtml(Account account, Jid from) {
+        String resource = from.getResource();
+        if (resource == null) {
+            return false;
+        }
+        Presence presence = account.getRoster().getContact(from).getPresences().getPresencesMap().get(resource);
+        ServiceDiscoveryResult disco = presence == null ? null : presence.getServiceDiscoveryResult();
+        if (disco == null) {
+            return false;
+        }
+        return hasIdentityKnowForSendingHtml(disco.getIdentities());
+    }
+
+    private static boolean hasIdentityKnowForSendingHtml(List<ServiceDiscoveryResult.Identity> identities) {
+        for (ServiceDiscoveryResult.Identity identity : identities) {
+            if (identity.getName() != null) {
+                if (CLIENTS_SENDING_HTML_IN_OTR.contains(identity.getName())) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
     private boolean extractChatState(Conversation c, final boolean isTypeGroupChat, final MessagePacket packet) {
         ChatState state = ChatState.parse(packet);
         if (state != null && c != null) {
@@ -126,6 +161,70 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
         return false;
     }
 
+    private Message parseOtrChat(String body, Jid from, String id, Conversation conversation) {
+        String presence;
+        if (from.isBareJid()) {
+            presence = "";
+        } else {
+            presence = from.getResource();
+        }
+        if (body.matches("^\\?OTRv\\d{1,2}\\?.*")) {
+            conversation.endOtrIfNeeded();
+        }
+        if (!conversation.hasValidOtrSession()) {
+            conversation.startOtrSession(presence, false);
+        } else {
+            String foreignPresence = conversation.getOtrSession().getSessionID().getUserID();
+            if (!foreignPresence.equals(presence)) {
+                conversation.endOtrIfNeeded();
+                conversation.startOtrSession(presence, false);
+            }
+        }
+        try {
+            conversation.setLastReceivedOtrMessageId(id);
+            Session otrSession = conversation.getOtrSession();
+            body = otrSession.transformReceiving(body);
+            SessionStatus status = otrSession.getSessionStatus();
+            if (body == null && status == SessionStatus.ENCRYPTED) {
+                mXmppConnectionService.onOtrSessionEstablished(conversation);
+                return null;
+            } else if (body == null && status == SessionStatus.FINISHED) {
+                conversation.resetOtrSession();
+                mXmppConnectionService.updateConversationUi();
+                return null;
+            } else if (body == null || (body.isEmpty())) {
+                return null;
+            }
+            if (body.startsWith(CryptoHelper.FILETRANSFER)) {
+                String key = body.substring(CryptoHelper.FILETRANSFER.length());
+                conversation.setSymmetricKey(CryptoHelper.hexToBytes(key));
+                return null;
+            }
+            if (clientMightSendHtml(conversation.getAccount(), from)) {
+                Log.d(Config.LOGTAG, conversation.getAccount().getJid().asBareJid() + ": received OTR message from bad behaving client. escaping HTML…");
+                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
+                    body = Html.fromHtml(body, Html.FROM_HTML_MODE_LEGACY).toString();
+                } else {
+                    body = Html.fromHtml(body).toString();
+                }
+            }
+
+            final OtrService otrService = conversation.getAccount().getOtrService();
+            Message finishedMessage = new Message(conversation, body, Message.ENCRYPTION_OTR, Message.STATUS_RECEIVED);
+            finishedMessage.setFingerprint(otrService.getFingerprint(otrSession.getRemotePublicKey()));
+            conversation.setLastReceivedOtrMessageId(null);
+
+            if (body.startsWith("?OTR")) {
+                return null;
+            }
+
+            return finishedMessage;
+        } catch (Exception e) {
+            conversation.resetOtrSession();
+            return null;
+        }
+    }
+
     private Message parseAxolotlChat(Element axolotlMessage, Jid from, Conversation conversation, int status, final boolean checkedForDuplicates, boolean postpone) {
         final AxolotlService service = conversation.getAccount().getAxolotlService();
         final XmppAxolotlMessage xmppAxolotlMessage;
@@ -327,6 +426,11 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
             final Jid from = packet.getFrom();
             final String id = packet.getId();
             if (from != null && id != null) {
+                final Message message = mXmppConnectionService.markMessage(account,
+                        from.asBareJid(),
+                        packet.getId(),
+                        Message.STATUS_SEND_FAILED,
+                        extractErrorMessage(packet));
                 if (id.startsWith(JingleRtpConnection.JINGLE_MESSAGE_PROPOSE_ID_PREFIX)) {
                     final String sessionId = id.substring(JingleRtpConnection.JINGLE_MESSAGE_PROPOSE_ID_PREFIX.length());
                     mXmppConnectionService.getJingleConnectionManager()
@@ -335,8 +439,8 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
                 }
                 if (id.startsWith(JingleRtpConnection.JINGLE_MESSAGE_PROCEED_ID_PREFIX)) {
                     final String sessionId = id.substring(JingleRtpConnection.JINGLE_MESSAGE_PROCEED_ID_PREFIX.length());
-                    final String message = extractErrorMessage(packet);
-                    mXmppConnectionService.getJingleConnectionManager().failProceed(account, from, sessionId, message);
+                    final String errorMessage = extractErrorMessage(packet);
+                    mXmppConnectionService.getJingleConnectionManager().failProceed(account, from, sessionId, errorMessage);
                     return true;
                 }
                 mXmppConnectionService.markMessage(account,
@@ -355,6 +459,13 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
                         }
                     }
                 }
+
+                if (message != null) {
+                    if (message.getEncryption() == Message.ENCRYPTION_OTR) {
+                        Conversation conversation = (Conversation) message.getConversation();
+                        conversation.endOtrIfNeeded();
+                    }
+                }
             }
             return true;
         }
@@ -368,6 +479,7 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
         }
         final MessagePacket packet;
         Long timestamp = null;
+        final boolean isForwarded;
         boolean isCarbon = false;
         String serverMsgId = null;
         final Element fin = original.findChild("fin", MessageArchiveService.Version.MAM_0.namespace);
@@ -385,7 +497,9 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
             }
             timestamp = f.second;
             packet = f.first;
+            isForwarded = true;
             serverMsgId = result.getAttribute("id");
+
             query.incrementMessageCount();
             if (handleErrorMessage(account, packet)) {
                 return;
@@ -403,8 +517,10 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
             }
             timestamp = f != null ? f.second : null;
             isCarbon = f != null;
+            isForwarded = isCarbon;
         } else {
             packet = original;
+            isForwarded = false;
         }
 
         if (timestamp == null) {
@@ -449,6 +565,7 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
             Log.e(Config.LOGTAG, account.getJid().asBareJid() + ": received groupchat (" + from + ") message on regular MAM request. skipping");
             return;
         }
+        boolean isProperlyAddressed = (to != null) && (!to.isBareJid() || account.countPresences() == 0);
         boolean isMucStatusMessage = InvalidJid.hasValidFrom(packet) && from.isBareJid() && mucUserElement != null && mucUserElement.hasChild("status");
         boolean selfAddressed;
         if (packet.fromAccount(account)) {
@@ -483,7 +600,10 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
 
         final boolean conversationIsProbablyMuc = isTypeGroupChat || mucUserElement != null || account.getXmppConnection().getMucServersWithholdAccount().contains(counterpart.getDomain().toEscapedString());
 
-        if (conversationIsProbablyMuc && !isTypeGroupChat) {
+        final boolean isOTR = body != null && body.content.startsWith("?OTR") && Config.supportOtr();
+        final boolean correctOTR = !isForwarded && !isTypeGroupChat && isProperlyAddressed;
+
+        if ((conversationIsProbablyMuc && !isTypeGroupChat) || (!Strings.isNullOrEmpty(counterpart.getResource()) && isOTR && correctOTR)) {
             nextCounterpart = counterpart;
         }
 
@@ -508,10 +628,6 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
             }
         }
 
-        if (nextCounterpart != null && mXmppConnectionService.checkIsArchived(account, counterpart.asBareJid(), nextCounterpart)) {
-            return;
-        }
-
         if ((body != null || pgpEncrypted != null || (axolotlEncrypted != null && axolotlEncrypted.hasChild("payload")) || oobUrl != null) && !isMucStatusMessage) {
             final Conversation conversation = mXmppConnectionService.findOrCreateConversation(account, counterpart.asBareJid(), null, conversationIsProbablyMuc, nextCounterpart != null, false, nextCounterpart);
             final boolean conversationMultiMode = conversation.getMode() == Conversation.MODE_MULTI;
@@ -551,7 +667,17 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
                 }
             }
             final Message message;
-            if (pgpEncrypted != null && Config.supportOpenPgp()) {
+            if (isOTR) {
+                if (correctOTR && !conversationMultiMode) {
+                    message = parseOtrChat(body.content, from, remoteMsgId, conversation);
+                    if (message == null) {
+                        return;
+                    }
+                } else {
+                    Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": ignoring OTR message from " + from + " isForwarded=" + Boolean.toString(isForwarded) + ", isProperlyAddressed=" + Boolean.valueOf(isProperlyAddressed));
+                    return;
+                }
+            } else if (pgpEncrypted != null && Config.supportOpenPgp()) {
                 message = new Message(conversation, pgpEncrypted, Message.ENCRYPTION_PGP, status);
             } else if (axolotlEncrypted != null && Config.supportOmemo()) {
                 Jid origin;
@@ -800,6 +926,13 @@ public class MessageParser extends AbstractParser implements OnMessagePacketRece
                 processMessageReceipts(account, packet, remoteMsgId, query);
             }
 
+            if (message.getStatus() == Message.STATUS_RECEIVED
+                    && conversation.getOtrSession() != null
+                    && !conversation.getOtrSession().getSessionID().getUserID()
+                    .equals(message.getCounterpart().getResource())) {
+                conversation.endOtrIfNeeded();
+            }
+
             mXmppConnectionService.databaseBackend.createMessage(message);
             final HttpConnectionManager manager = this.mXmppConnectionService.getHttpConnectionManager();
             if (message.trusted() && message.treatAsDownloadable() && manager.getAutoAcceptFileSize() > 0) {

src/main/java/eu/siacs/conversations/persistance/DatabaseBackend.java

@@ -50,6 +50,7 @@ import eu.siacs.conversations.crypto.axolotl.SQLiteAxolotlStore;
 import eu.siacs.conversations.entities.Account;
 import eu.siacs.conversations.entities.Contact;
 import eu.siacs.conversations.entities.Conversation;
+import eu.siacs.conversations.entities.Conversational;
 import eu.siacs.conversations.entities.Message;
 import eu.siacs.conversations.entities.PresenceTemplate;
 import eu.siacs.conversations.entities.Roster;
@@ -887,30 +888,40 @@ public class DatabaseBackend extends SQLiteOpenHelper {
         String comparsionOperation = isForward ? ">?" : "<?";
         String sorting = isForward ? " ASC" : " DESC";
         if (timestamp == -1) {
-            if (conversation.getNextCounterpart() == null) {
-                String[] selectionArgs = {conversation.getUuid()};
-                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
-                        + "=?", selectionArgs, null, null, Message.TIME_SENT
-                        + sorting, String.valueOf(limit));
-            } else {
+            if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart() && conversation.getMode() == Conversational.MODE_MULTI) {
                 String[] selectionArgs = {conversation.getUuid(), String.valueOf(Message.TYPE_PRIVATE), String.valueOf(Message.TYPE_PRIVATE_FILE), conversation.getNextCounterpart().toString()};
                 cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
                     + "=? and (" + Message.TYPE + "=? or " + Message.TYPE + "=?) and " + Message.COUNTERPART + "=?" , selectionArgs, null, null, Message.TIME_SENT
                     + sorting, String.valueOf(limit));
+            } else if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart()) {
+                String[] selectionArgs = {conversation.getUuid(), String.valueOf(Message.ENCRYPTION_OTR), conversation.getNextCounterpart().toString()};
+                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
+                        + "=? and " + Message.ENCRYPTION + "=? and " + Message.COUNTERPART + "=?" , selectionArgs, null, null, Message.TIME_SENT
+                        + sorting, String.valueOf(limit));
+            } else {
+                String[] selectionArgs = {conversation.getUuid()};
+                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
+                        + "=?", selectionArgs, null, null, Message.TIME_SENT
+                        + sorting, String.valueOf(limit));
             }
         } else {
-            if (conversation.getNextCounterpart() == null) {
+            if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart() && conversation.getMode() == Conversational.MODE_MULTI) {
+                String[] selectionArgs = {conversation.getUuid(), String.valueOf(Message.TYPE_PRIVATE), String.valueOf(Message.TYPE_PRIVATE_FILE), conversation.getNextCounterpart().toString(), Long.toString(timestamp)};
+                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
+                        + "=? and (" + Message.TYPE + "=? or " + Message.TYPE + "=?) and " + Message.COUNTERPART + "=? and " + Message.TIME_SENT + comparsionOperation, selectionArgs, null, null, Message.TIME_SENT
+                        + sorting, String.valueOf(limit));
+            } else if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart()) {
+                String[] selectionArgs = {conversation.getUuid(), String.valueOf(Message.ENCRYPTION_OTR), conversation.getNextCounterpart().toString(), Long.toString(timestamp)};
+                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
+                        + "=? and " + Message.ENCRYPTION + "=? and " + Message.COUNTERPART + "=? and " + Message.TIME_SENT + comparsionOperation, selectionArgs, null, null, Message.TIME_SENT
+                        + sorting, String.valueOf(limit));
+            } else {
                 String[] selectionArgs = {conversation.getUuid(),
                         Long.toString(timestamp)};
                 cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
                                 + "=? and " + Message.TIME_SENT + comparsionOperation, selectionArgs,
                         null, null, Message.TIME_SENT + sorting,
                         String.valueOf(limit));
-            } else {
-                String[] selectionArgs = {conversation.getUuid(), String.valueOf(Message.TYPE_PRIVATE), String.valueOf(Message.TYPE_PRIVATE_FILE), conversation.getNextCounterpart().toString(), Long.toString(timestamp)};
-                cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
-                        + "=? and (" + Message.TYPE + "=? or " + Message.TYPE + "=?) and " + Message.COUNTERPART + "=? and " + Message.TIME_SENT + comparsionOperation, selectionArgs, null, null, Message.TIME_SENT
-                        + sorting, String.valueOf(limit));
             }
         }
         CursorUtils.upgradeCursorWindowSize(cursor);
@@ -1084,7 +1095,7 @@ public class DatabaseBackend extends SQLiteOpenHelper {
 
             try(final Cursor cursor = db.query(Conversation.TABLENAME, null,
                     Conversation.ACCOUNT + "=? AND (" + Conversation.CONTACTJID
-                            + " like ? OR " + Conversation.CONTACTJID + "=?)", selectionArgs, null, null, null)) {
+                            + " like ? OR " + Conversation.CONTACTJID + "=?) AND " + Conversation.NEXT_COUNTERPART + " =NULL", selectionArgs, null, null, null)) {
                 if (cursor.getCount() == 0) {
                     return null;
                 }
@@ -1101,6 +1112,37 @@ public class DatabaseBackend extends SQLiteOpenHelper {
         return null;
     }
 
+    public boolean deleteConversation(final Account account, final Jid contactJid, final Jid counterpart) {
+        SQLiteDatabase db = this.getWritableDatabase();
+
+        if (counterpart != null) {
+            String[] selectionArgs = {account.getUuid(),
+                    contactJid.asBareJid().toString() + "/%",
+                    contactJid.asBareJid().toString(),
+                    counterpart.toString()
+            };
+
+            int rows = db.delete(Conversation.TABLENAME,
+                    Conversation.ACCOUNT + "=? AND (" + Conversation.CONTACTJID
+                            + " like ? OR " + Conversation.CONTACTJID + "=?) AND " + Conversation.NEXT_COUNTERPART + "=?", selectionArgs);
+
+            return rows == 1;
+        } else {
+            String[] selectionArgs = new String[]{
+                    account.getUuid(),
+                    contactJid.asBareJid().toString() + "/%",
+                    contactJid.asBareJid().toString()
+            };
+
+            int rows = db.delete(Conversation.TABLENAME,
+                    Conversation.ACCOUNT + "=? AND (" + Conversation.CONTACTJID
+                            + " like ? OR " + Conversation.CONTACTJID + "=?) AND " + Conversation.NEXT_COUNTERPART + " =NULL", selectionArgs);
+
+            return rows == 1;
+
+        }
+    }
+
     public void updateConversation(final Conversation conversation) {
         final SQLiteDatabase db = this.getWritableDatabase();
         final String[] args = {conversation.getUuid()};

src/main/java/eu/siacs/conversations/services/XmppConnectionService.java

@@ -61,6 +61,11 @@ import com.google.common.base.Objects;
 import com.google.common.base.Optional;
 import com.google.common.base.Strings;
 
+import net.java.otr4j.session.Session;
+import net.java.otr4j.session.SessionID;
+import net.java.otr4j.session.SessionImpl;
+import net.java.otr4j.session.SessionStatus;
+
 import org.conscrypt.Conscrypt;
 import org.jxmpp.stringprep.libidn.LibIdnXmppStringprep;
 import org.openintents.openpgp.IOpenPgpService2;
@@ -171,6 +176,7 @@ import eu.siacs.conversations.xmpp.OnUpdateBlocklist;
 import eu.siacs.conversations.xmpp.XmppConnection;
 import eu.siacs.conversations.xmpp.chatstate.ChatState;
 import eu.siacs.conversations.xmpp.forms.Data;
+import eu.siacs.conversations.xmpp.jid.OtrJidHelper;
 import eu.siacs.conversations.xmpp.jingle.AbstractJingleConnection;
 import eu.siacs.conversations.xmpp.jingle.JingleConnectionManager;
 import eu.siacs.conversations.xmpp.jingle.JingleRtpConnection;
@@ -255,9 +261,18 @@ public class XmppConnectionService extends Service {
         Conversation conversation = find(getConversations(), contact);
         if (conversation != null) {
             if (online) {
+                conversation.endOtrIfNeeded();
                 if (contact.getPresences().size() == 1) {
                     sendUnsentMessages(conversation);
                 }
+            } else {
+                //check if the resource we are haveing a conversation with is still online
+                if (conversation.hasValidOtrSession()) {
+                    String otrResource = conversation.getOtrSession().getSessionID().getUserID();
+                    if (!(Arrays.asList(contact.getPresences().toResourceArray()).contains(otrResource))) {
+                        conversation.endOtrIfNeeded();
+                    }
+                }
             }
         }
     };
@@ -447,6 +462,9 @@ public class XmppConnectionService extends Service {
                     if (conversation.getAccount() == account
                             && !pendingJoin
                             && !inProgressJoin) {
+                        if (!conversation.startOtrIfNeeded()) {
+                            Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": couldn't start OTR with " + conversation.getContact().getJid() + " when needed");
+                        }
                         sendUnsentMessages(conversation);
                     }
                 }
@@ -1704,6 +1722,12 @@ public class XmppConnectionService extends Service {
             }
         }
 
+        if (!resend && message.getEncryption() != Message.ENCRYPTION_OTR) {
+            conversation.endOtrIfNeeded();
+            conversation.findUnsentMessagesWithEncryption(Message.ENCRYPTION_OTR,
+                    message1 -> markMessage(message1, Message.STATUS_SEND_FAILED));
+        }
+
         final boolean inProgressJoin = isJoinInProgress(conversation);
 
 
@@ -1736,6 +1760,30 @@ public class XmppConnectionService extends Service {
                         packet = mMessageGenerator.generatePgpChat(message);
                     }
                     break;
+                case Message.ENCRYPTION_OTR:
+                    SessionImpl otrSession = conversation.getOtrSession();
+                    if (otrSession != null && otrSession.getSessionStatus() == SessionStatus.ENCRYPTED) {
+                        try {
+                            message.setCounterpart(OtrJidHelper.fromSessionID(otrSession.getSessionID()));
+                        } catch (IllegalArgumentException e) {
+                            break;
+                        }
+                        if (message.needsUploading()) {
+                            mJingleConnectionManager.startJingleFileTransfer(message);
+                        } else {
+                            packet = mMessageGenerator.generateOtrChat(message);
+                        }
+                    } else if (otrSession == null) {
+                        if (message.fixCounterpart()) {
+                            conversation.startOtrSession(message.getCounterpart().getResource(), true);
+                        } else {
+                            Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": could not fix counterpart for OTR message to contact " + message.getCounterpart());
+                            break;
+                        }
+                    } else {
+                        Log.d(Config.LOGTAG, account.getJid().asBareJid() + " OTR session with " + message.getContact() + " is in wrong state: " + otrSession.getSessionStatus().toString());
+                    }
+                    break;
                 case Message.ENCRYPTION_AXOLOTL:
                     message.setFingerprint(account.getAxolotlService().getOwnFingerprint());
                     if (message.needsUploading()) {
@@ -1789,6 +1837,12 @@ public class XmppConnectionService extends Service {
                         }
                     }
                     break;
+                case Message.ENCRYPTION_OTR:
+                    if (!conversation.hasValidOtrSession() && message.getCounterpart() != null) {
+                        Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": create otr session without starting for " + message.getContact().getJid());
+                        conversation.startOtrSession(message.getCounterpart().getResource(), false);
+                    }
+                    break;
                 case Message.ENCRYPTION_AXOLOTL:
                     message.setFingerprint(account.getAxolotlService().getOwnFingerprint());
                     break;
@@ -2446,7 +2500,9 @@ public class XmppConnectionService extends Service {
                         query.setCallback(callback);
                         callback.informUser(R.string.fetching_history_from_server);
                     } else {
-                        callback.informUser(R.string.not_fetching_history_retention_period);
+                        if (conversation.getMode() != Conversational.MODE_SINGLE || !conversation.hasPermanentCounterpart()) {
+                            callback.informUser(R.string.not_fetching_history_retention_period);
+                        }
                     }
 
                 }
@@ -2496,6 +2552,7 @@ public class XmppConnectionService extends Service {
                 if ((account == null || conversation.getAccount() == account)
                         && (conversation.getJid().asBareJid().equals(jid.asBareJid()))
                         && Objects.equal(conversation.getNextCounterpart(), counterpart)
+                        && conversation.hasPermanentCounterpart()
                 ) {
                     return conversation;
                 }
@@ -2504,7 +2561,7 @@ public class XmppConnectionService extends Service {
             for (final Conversation conversation : haystack) {
                 if ((account == null || conversation.getAccount() == account)
                         && (conversation.getJid().asBareJid().equals(jid.asBareJid()))
-                        && conversation.getNextCounterpart() == null
+                        && (conversation.getNextCounterpart() == null || !conversation.hasPermanentCounterpart())
                 ) {
                     return conversation;
                 }
@@ -2566,6 +2623,7 @@ public class XmppConnectionService extends Service {
             if (conversation != null) {
                 return conversation;
             }
+
             conversation = databaseBackend.findConversation(account, jid, counterpart);
             final boolean loadMessagesFromDb;
             if (conversation != null) {
@@ -2647,6 +2705,18 @@ public class XmppConnectionService extends Service {
         archiveConversation(conversation, true);
     }
 
+    public void destroyConversation(Conversation conversation) {
+        archiveConversation(conversation);
+        final Runnable runnable = () -> {
+            databaseBackend.deleteMessagesInConversation(conversation);
+
+            if (!databaseBackend.deleteConversation(conversation.getAccount(), conversation.getContactJid().asBareJid(), conversation.getNextCounterpart())) {
+                Log.d(Config.LOGTAG, conversation.getJid().asBareJid() + ": unable to delete conversation");
+            }
+        };
+        mDatabaseWriterExecutor.execute(runnable);
+    }
+
     private void archiveConversation(Conversation conversation, final boolean maySynchronizeWithBookmarks) {
         getNotificationService().clear(conversation);
         conversation.setStatus(Conversation.STATUS_ARCHIVED);
@@ -2675,6 +2745,7 @@ public class XmppConnectionService extends Service {
                     stopPresenceUpdatesTo(conversation.getContact());
                 }
             }
+            conversation.endOtrIfNeeded();
             updateConversation(conversation);
             this.conversations.remove(conversation);
             updateConversationUi();
@@ -3922,6 +3993,12 @@ public class XmppConnectionService extends Service {
                 if (conversation.getAccount() == account) {
                     if (conversation.getMode() == Conversation.MODE_MULTI) {
                         leaveMuc(conversation, true);
+                    } else {
+                        if (conversation.endOtrIfNeeded()) {
+                            Log.d(Config.LOGTAG, account.getJid().asBareJid()
+                                    + ": ended otr session with "
+                                    + conversation.getJid());
+                        }
                     }
                 }
             }
@@ -3978,6 +4055,39 @@ public class XmppConnectionService extends Service {
         pushContactToServer(contact, preAuth);
     }
 
+    public void onOtrSessionEstablished(Conversation conversation) {
+        final Account account = conversation.getAccount();
+        final Session otrSession = conversation.getOtrSession();
+        Log.d(Config.LOGTAG,
+                account.getJid().asBareJid() + " otr session established with "
+                        + conversation.getJid() + "/"
+                        + otrSession.getSessionID().getUserID());
+        conversation.findUnsentMessagesWithEncryption(Message.ENCRYPTION_OTR, new Conversation.OnMessageFound() {
+
+            @Override
+            public void onMessageFound(Message message) {
+                SessionID id = otrSession.getSessionID();
+                try {
+                    message.setCounterpart(Jid.of(id.getAccountID() + "/" + id.getUserID()));
+                } catch (IllegalArgumentException e) {
+                    return;
+                }
+                if (message.needsUploading()) {
+                    mJingleConnectionManager.startJingleFileTransfer(message);
+                } else {
+                    MessagePacket outPacket = mMessageGenerator.generateOtrChat(message);
+                    if (outPacket != null) {
+                        mMessageGenerator.addDelay(outPacket, message.getTimeSent());
+                        message.setStatus(Message.STATUS_SEND);
+                        databaseBackend.updateMessage(message, false);
+                        sendMessagePacket(account, outPacket);
+                    }
+                }
+                updateConversationUi();
+            }
+        });
+    }
+
     public void pushContactToServer(final Contact contact) {
         pushContactToServer(contact, null);
     }
@@ -4503,6 +4613,7 @@ public class XmppConnectionService extends Service {
             return false;
         } else {
             final Message message = conversation.findSentMessageWithUuid(uuid);
+
             if (message != null) {
                 if (message.getServerMsgId() == null) {
                     message.setServerMsgId(serverMessageId);
@@ -4805,6 +4916,11 @@ public class XmppConnectionService extends Service {
         setMemorizingTrustManager(tm);
     }
 
+    public void syncRosterToDisk(final Account account) {
+        Runnable runnable = () -> databaseBackend.writeRoster(account.getRoster());
+        mDatabaseWriterExecutor.execute(runnable);
+    }
+
     public LruCache<String, Bitmap> getBitmapCache() {
         return this.mBitmapCache;
     }
@@ -5272,10 +5388,14 @@ public class XmppConnectionService extends Service {
     }
 
     public boolean verifyFingerprints(Contact contact, List<XmppUri.Fingerprint> fingerprints) {
+        boolean needsRosterWrite = false;
         boolean performedVerification = false;
         final AxolotlService axolotlService = contact.getAccount().getAxolotlService();
         for (XmppUri.Fingerprint fp : fingerprints) {
-            if (fp.type == XmppUri.FingerprintType.OMEMO) {
+            if (fp.type == XmppUri.FingerprintType.OTR) {
+                performedVerification |= contact.addOtrFingerprint(fp.fingerprint);
+                needsRosterWrite |= performedVerification;
+            } else if (fp.type == XmppUri.FingerprintType.OMEMO) {
                 String fingerprint = "05" + fp.fingerprint.replaceAll("\\s", "");
                 FingerprintStatus fingerprintStatus = axolotlService.getFingerprintTrust(fingerprint);
                 if (fingerprintStatus != null) {
@@ -5288,6 +5408,11 @@ public class XmppConnectionService extends Service {
                 }
             }
         }
+
+        if (needsRosterWrite) {
+            syncRosterToDisk(contact.getAccount());
+        }
+
         return performedVerification;
     }
 

src/main/java/eu/siacs/conversations/ui/ContactDetailsActivity.java

@@ -504,7 +504,7 @@ public class ContactDetailsActivity extends OmemoActivity implements OnAccountUp
                     && contact.getLastseen() > 0
                     && contact.getPresences().allOrNonSupport(Namespace.IDLE)) {
                 binding.detailsLastseen.setVisibility(View.VISIBLE);
-                binding.detailsLastseen.setText(UIHelper.lastseen(getApplicationContext(), contact.isActive(), contact.getLastseen()));
+                binding.detailsLastseen.setText(UIHelper.lastseen(getApplicationContext(), contact.isActive(), contact.getLastseen(), false));
             } else {
                 binding.detailsLastseen.setVisibility(View.GONE);
             }
@@ -523,7 +523,7 @@ public class ContactDetailsActivity extends OmemoActivity implements OnAccountUp
         AvatarWorkerTask.loadAvatar(contact, binding.detailsContactBadge, R.dimen.avatar_on_details_screen_size);
         binding.detailsContactBadge.setOnClickListener(this::onBadgeClick);
 
-        binding.presenceIndicator.setStatus(contact.getShownStatus());
+        binding.presenceIndicator.setStatus(contact);
 
         binding.detailsContactKeys.removeAllViews();
         boolean hasKeys = false;

src/main/java/eu/siacs/conversations/ui/ConversationFragment.java

@@ -79,6 +79,8 @@ import androidx.viewpager.widget.PagerAdapter;
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
 
+import net.java.otr4j.session.SessionStatus;
+
 import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
@@ -223,6 +225,14 @@ public class ConversationFragment extends XmppFragment
     private ConversationsActivity activity;
     private Vibrator vibrator;
     private boolean reInitRequiredOnStart = true;
+
+    protected OnClickListener clickToVerify = new OnClickListener() {
+        @Override
+        public void onClick(View v) {
+            activity.verifyOtrSessionDialog(conversation, v);
+        }
+    };
+
     @ColorInt
     private int primaryColor = -1;
 
@@ -534,6 +544,20 @@ public class ConversationFragment extends XmppFragment
                     }
                 }
             };
+
+    private OnClickListener mAnswerSmpClickListener = new OnClickListener() {
+        @Override
+        public void onClick(View view) {
+            Intent intent = new Intent(activity, VerifyOTRActivity.class);
+            intent.setAction(VerifyOTRActivity.ACTION_VERIFY_CONTACT);
+            intent.putExtra(EXTRA_ACCOUNT, conversation.getAccount().getJid().asBareJid().toString());
+            intent.putExtra(VerifyOTRActivity.EXTRA_ACCOUNT, conversation.getAccount().getJid().asBareJid().toString());
+            intent.putExtra("mode", VerifyOTRActivity.MODE_ANSWER_QUESTION);
+            startActivity(intent);
+            activity.overridePendingTransition(R.animator.fade_in, R.animator.fade_out);
+        }
+    };
+
     protected OnClickListener clickToDecryptListener =
             new OnClickListener() {
 
@@ -590,7 +614,7 @@ public class ConversationFragment extends XmppFragment
                 public void onClick(View v) {
                     stopScrolling();
 
-                    if (previousClickedReply != null) {
+                    /*if (previousClickedReply != null) {
                         int lastVisiblePosition = binding.messagesView.getLastVisiblePosition();
                         Message lastVisibleMessage = messageListAdapter.getItem(lastVisiblePosition);
                         Message jump = previousClickedReply;
@@ -602,7 +626,7 @@ public class ConversationFragment extends XmppFragment
                                 return;
                             }
                         }
-                    }
+                    }*/
 
                     if (conversation.isInHistoryPart()) {
                         conversation.jumpToLatest();
@@ -1064,6 +1088,9 @@ public class ConversationFragment extends XmppFragment
             message.setUuid(UUID.randomUUID().toString());
         }
         switch (conversation.getNextEncryption()) {
+            case Message.ENCRYPTION_OTR:
+                sendOtrMessage(message);
+                break;
             case Message.ENCRYPTION_PGP:
                 sendPgpMessage(message);
                 break;
@@ -1380,8 +1407,16 @@ public class ConversationFragment extends XmppFragment
         final MenuItem menuVideoCall = menu.findItem(R.id.action_video_call);
         final MenuItem menuTogglePinned = menu.findItem(R.id.action_toggle_pinned);
         final MenuItem deleteCustomBg = menu.findItem(R.id.action_delete_custom_bg);
+        final MenuItem startSecretChat = menu.findItem(R.id.action_start_secret_chat);
+        final MenuItem destroySecretChat = menu.findItem(R.id.action_destroy_secret_chat);
+        final MenuItem encryption = menu.findItem(R.id.action_security);
 
         if (conversation != null) {
+            boolean considerAsSecretChat = conversation.getMode() == Conversational.MODE_SINGLE &&
+                    conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart();
+
+
+            destroySecretChat.setVisible(false);
             if (conversation.getMode() == Conversation.MODE_MULTI) {
                 menuContactDetails.setVisible(false);
                 menuInviteContact.setVisible(conversation.getMucOptions().canInvite() && conversation.getNextCounterpart() == null);
@@ -1391,7 +1426,12 @@ public class ConversationFragment extends XmppFragment
                                 : R.string.channel_details);
                 menuCall.setVisible(false);
                 menuOngoingCall.setVisible(false);
+                startSecretChat.setVisible(false);
             } else {
+                if (considerAsSecretChat) {
+                    startSecretChat.setVisible(false);
+                    destroySecretChat.setVisible(true);
+                }
                 menuMucParticipants.setVisible(false);
                 final XmppConnectionService service =
                         activity == null ? null : activity.xmppConnectionService;
@@ -1432,6 +1472,10 @@ public class ConversationFragment extends XmppFragment
                 menuTogglePinned.setTitle(R.string.add_to_favorites);
             }
 
+            if (considerAsSecretChat) {
+                encryption.setVisible(false);
+            }
+
             deleteCustomBg.setVisible(ChatBackgroundHelper.getBgFile(activity, conversation.getUuid()).exists());
         }
 
@@ -2022,6 +2066,12 @@ public class ConversationFragment extends XmppFragment
             case R.id.action_archive:
                 activity.xmppConnectionService.archiveConversation(conversation);
                 break;
+            case R.id.action_start_secret_chat:
+                startOtrChat();
+                break;
+            case R.id.action_destroy_secret_chat:
+                destroySecrectChat();
+                break;
             case R.id.action_contact_details:
                 activity.switchToContactDetails(conversation.getContact());
                 break;
@@ -3550,6 +3600,14 @@ public class ConversationFragment extends XmppFragment
             }
         } else if (account.hasPendingPgpIntent(conversation)) {
             showSnackbar(R.string.openpgp_messages_found, R.string.decrypt, clickToDecryptListener);
+        } else if (mode == Conversation.MODE_SINGLE
+                && conversation.smpRequested()) {
+            showSnackbar(R.string.smp_requested, R.string.verify, this.mAnswerSmpClickListener);
+        } else if (mode == Conversation.MODE_SINGLE
+                && conversation.hasValidOtrSession()
+                && (conversation.getOtrSession().getSessionStatus() == SessionStatus.ENCRYPTED)
+                && (!conversation.isOtrFingerprintVerified())) {
+            showSnackbar(R.string.unknown_otr_fingerprint, R.string.verify, clickToVerify);
         } else if (connection != null
                 && connection.getFeatures().blocking()
                 && conversation.countMessages() != 0
@@ -3610,7 +3668,7 @@ public class ConversationFragment extends XmppFragment
                 conversation.refreshSessions();
 
 
-                if (conversation != null && conversation.getMode() == Conversational.MODE_MULTI) {
+                if (conversation != null && conversation.getMode() == Conversational.MODE_MULTI && conversation.getNextCounterpart() == null) {
                     String subject = conversation.getMucOptions().getSubject();
                     Boolean hidden = conversation.getMucOptions().subjectHidden();
 
@@ -3650,6 +3708,11 @@ public class ConversationFragment extends XmppFragment
             new Handler()
                     .post(
                             () -> {
+                                if (conversation.isInHistoryPart()) {
+                                    conversation.jumpToLatest();
+                                    refresh(false);
+                                }
+
                                 int size = messageList.size();
                                 this.binding.messagesView.setSelection(size - 1);
                             });
@@ -3937,6 +4000,31 @@ public class ConversationFragment extends XmppFragment
         messageSent();
     }
 
+    protected void sendOtrMessage(final Message message) {
+        final ConversationsActivity activity = (ConversationsActivity) getActivity();
+        final XmppConnectionService xmppService = activity.xmppConnectionService;
+        message.setCounterpart(conversation.getNextCounterpart());
+        xmppService.sendMessage(message);
+        messageSent();
+    }
+
+    protected void startOtrChat() {
+        final ConversationsActivity activity = (ConversationsActivity) getActivity();
+        activity.selectPresence(conversation,
+                () -> {
+                    Conversation c = activity.xmppConnectionService.findOrCreateConversation(conversation.getAccount(), conversation.getJid(), null, false, false, false, conversation.getNextCounterpart());
+                    conversation.setNextCounterpart(null);
+                    if (c != conversation) {
+                        activity.switchToConversation(c);
+                    }
+                });
+    }
+
+    private void destroySecrectChat() {
+        conversation.endOtrIfNeeded();
+        activity.xmppConnectionService.destroyConversation(conversation);
+    }
+
     protected void sendPgpMessage(final Message message) {
         final XmppConnectionService xmppService = activity.xmppConnectionService;
         final Contact contact = message.getConversation().getContact();

src/main/java/eu/siacs/conversations/ui/ConversationsActivity.java

@@ -42,10 +42,14 @@ import android.app.FragmentTransaction;
 import android.content.ActivityNotFoundException;
 import android.content.Context;
 import android.content.Intent;
+import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.Looper;
+import android.preference.PreferenceManager;
 import android.provider.Settings;
 import android.util.Log;
 import android.view.KeyEvent;
@@ -59,9 +63,12 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.ActionBar;
 import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.widget.PopupMenu;
 import androidx.core.app.ActivityCompat;
 import androidx.databinding.DataBindingUtil;
 
+import net.java.otr4j.session.SessionStatus;
+
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 import com.google.android.material.navigation.NavigationBarView;
 
@@ -95,10 +102,13 @@ import eu.siacs.conversations.ui.util.PendingItem;
 import eu.siacs.conversations.utils.ExceptionHelper;
 import eu.siacs.conversations.utils.PhoneNumberUtilWrapper;
 import eu.siacs.conversations.utils.SignupUtils;
+import eu.siacs.conversations.utils.UIHelper;
 import eu.siacs.conversations.utils.XmppUri;
+import eu.siacs.conversations.xml.Namespace;
 import eu.siacs.conversations.xmpp.Jid;
 import eu.siacs.conversations.xmpp.OnUpdateBlocklist;
 import io.michaelrocks.libphonenumber.android.NumberParseException;
+import me.drakeet.support.toast.ToastCompat;
 
 public class ConversationsActivity extends XmppActivity implements OnConversationSelected, OnConversationArchived, OnConversationsListItemUpdated, OnConversationRead, XmppConnectionService.OnAccountUpdate, XmppConnectionService.OnConversationUpdate, XmppConnectionService.OnRosterUpdate, OnUpdateBlocklist, XmppConnectionService.OnShowErrorToast, XmppConnectionService.OnAffiliationChanged {
 
@@ -135,6 +145,10 @@ public class ConversationsActivity extends XmppActivity implements OnConversatio
     private boolean mActivityPaused = true;
     private final AtomicBoolean mRedirectInProcess = new AtomicBoolean(false);
 
+    private final Handler handler = new Handler(Looper.getMainLooper());
+    private final Runnable refreshTitleRunnable = this::invalidateActionBarTitle;
+    private boolean showLastSeen = false;
+
     private static boolean isViewOrShareIntent(Intent i) {
         Log.d(Config.LOGTAG, "action: " + (i == null ? null : i.getAction()));
         return i != null && VIEW_AND_SHARE_ACTIONS.contains(i.getAction()) && i.hasExtra(EXTRA_CONVERSATION);
@@ -660,6 +674,8 @@ public class ConversationsActivity extends XmppActivity implements OnConversatio
             this.mSkipBackgroundBinding = false;
         }
         mRedirectInProcess.set(false);
+        final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
+        this.showLastSeen = preferences.getBoolean("last_activity", false);
 
         BottomNavigationView bottomNavigationView = findViewById(R.id.bottom_navigation);
         bottomNavigationView.setSelectedItemId(R.id.chats);
@@ -735,13 +751,18 @@ public class ConversationsActivity extends XmppActivity implements OnConversatio
         if (actionBar == null) {
             return;
         }
+
         final FragmentManager fragmentManager = getFragmentManager();
         final Fragment mainFragment = fragmentManager.findFragmentById(R.id.main_fragment);
         if (mainFragment instanceof ConversationFragment) {
             final Conversation conversation = ((ConversationFragment) mainFragment).getConversation();
             if (conversation != null) {
-                if (conversation.getNextCounterpart() != null) {
-                    actionBar.setTitle(getString(R.string.muc_private_conversation_title, conversation.getNextCounterpart().getResource(), conversation.getName()));
+                if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart()) {
+                    if (conversation.getMode() == Conversational.MODE_MULTI) {
+                        actionBar.setTitle(getString(R.string.muc_private_conversation_title, conversation.getNextCounterpart().getResource(), conversation.getName()));
+                    } else {
+                        actionBar.setTitle(getString(R.string.secret_chat_title_no_resource, conversation.getName()));
+                    }
                 } else {
                     actionBar.setTitle(conversation.getName());
                 }
@@ -750,10 +771,40 @@ public class ConversationsActivity extends XmppActivity implements OnConversatio
                         binding.toolbar,
                         (v) -> openConversationDetails(conversation)
                 );
+
+                if (conversation.getMode() == Conversation.MODE_MULTI && conversation.getNextCounterpart() == null) {
+                    int usersCount = conversation.getMucOptions().getUserCount();
+                    if (usersCount > 0) {
+                        actionBar.setSubtitle(getResources().getQuantityString(R.plurals.x_participants, conversation.getMucOptions().getUserCount(), conversation.getMucOptions().getUserCount()));
+                    } else {
+                        actionBar.setSubtitle("");
+                    }
+
+                    handler.postDelayed(refreshTitleRunnable, 5000L);
+                } else if (conversation.getMode() == Conversation.MODE_SINGLE) {
+                    Contact contact = conversation.getContact();
+                    List<String> statuses = contact.getPresences().getStatusMessages();
+                    if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart()) {
+                        actionBar.setSubtitle(conversation.getNextCounterpart().getResource());
+                    } else if (!statuses.isEmpty() && !statuses.get(0).isBlank()) {
+                        actionBar.setSubtitle(statuses.get(0));
+                        handler.postDelayed(refreshTitleRunnable, 5000L);
+                    } else {
+                        actionBar.setSubtitle("");
+                        handler.removeCallbacks(refreshTitleRunnable);
+                    }
+                } else {
+                    actionBar.setSubtitle("");
+                    handler.removeCallbacks(refreshTitleRunnable);
+                }
+
                 return;
             }
         }
+
+        handler.removeCallbacks(refreshTitleRunnable);
         actionBar.setTitle(R.string.app_name);
+        actionBar.setSubtitle("");
         actionBar.setDisplayHomeAsUpEnabled(false);
         ActionBarUtil.resetActionBarOnClickListeners(binding.toolbar);
     }
@@ -771,6 +822,41 @@ public class ConversationsActivity extends XmppActivity implements OnConversatio
         }
     }
 
+    public void verifyOtrSessionDialog(final Conversation conversation, View view) {
+        if (!conversation.hasValidOtrSession() || conversation.getOtrSession().getSessionStatus() != SessionStatus.ENCRYPTED) {
+            ToastCompat.makeText(this, R.string.otr_session_not_started, Toast.LENGTH_LONG).show();
+            return;
+        }
+        if (view == null) {
+            return;
+        }
+        PopupMenu popup = new PopupMenu(this, view);
+        popup.inflate(R.menu.verification_choices);
+        popup.setOnMenuItemClickListener(menuItem -> {
+            if (menuItem.getItemId() == R.id.blind_trust) {
+                conversation.verifyOtrFingerprint();
+                xmppConnectionService.syncRosterToDisk(conversation.getAccount());
+                refreshUiReal();
+                return true;
+            }
+
+            Intent intent = new Intent(ConversationsActivity.this, VerifyOTRActivity.class);
+            intent.setAction(VerifyOTRActivity.ACTION_VERIFY_CONTACT);
+            intent.putExtra("contact", conversation.getContact().getJid().asBareJid().toString());
+            intent.putExtra("counterpart", conversation.getNextCounterpart().toString());
+            intent.putExtra(EXTRA_ACCOUNT, conversation.getAccount().getJid().asBareJid().toString());
+            switch (menuItem.getItemId()) {
+                case R.id.ask_question:
+                    intent.putExtra("mode", VerifyOTRActivity.MODE_ASK_QUESTION);
+                    break;
+            }
+            startActivity(intent);
+            overridePendingTransition(R.animator.fade_in, R.animator.fade_out);
+            return true;
+        });
+        popup.show();
+    }
+
     @Override
     public void onConversationArchived(Conversation conversation) {
         if (performRedirectIfNecessary(conversation, false)) {

src/main/java/eu/siacs/conversations/ui/SendLogActivity.java

@@ -265,7 +265,6 @@ public class SendLogActivity extends ActionBarActivity {
                     log.insert(0, mAdditonalInfo);
                 }
 
-                android.util.Log.e("35fd", log.toString());
                 writer.write(log.toString());
             } 
             catch (IOException e){

src/main/java/eu/siacs/conversations/ui/StartConversationActivity.java

@@ -1310,6 +1310,21 @@ public class StartConversationActivity extends XmppActivity implements XmppConne
         }
     }
 
+    protected void startOtrChat() {
+        int position = contact_context_id;
+        Contact contact = (Contact) contacts.get(position);
+
+        Conversation conversation = xmppConnectionService.findOrCreateConversation(contact.getAccount(), contact.getJid(), null, false, false, false, null);
+
+        selectPresence(conversation,
+                () -> {
+                    Conversation c = xmppConnectionService.findOrCreateConversation(contact.getAccount(), contact.getJid(), null, false, false, false, conversation.getNextCounterpart());
+                    conversation.setNextCounterpart(null);
+                    if (c != null) {
+                        switchToConversation(c);
+                    }
+                });
+    }
 
     private void setRefreshing(boolean refreshing) {
         MyListFragment fragment = (MyListFragment) mListPagerAdapter.getItem(0);
@@ -1451,9 +1466,12 @@ public class StartConversationActivity extends XmppActivity implements XmppConne
                 final MenuItem blockUnblockItem = menu.findItem(R.id.context_contact_block_unblock);
                 final MenuItem showContactDetailsItem = menu.findItem(R.id.context_contact_details);
                 final MenuItem deleteContactMenuItem = menu.findItem(R.id.context_delete_contact);
+                final MenuItem startSecrectChat = menu.findItem(R.id.context_contact_start_secrect_chat);
                 if (contact.isSelf()) {
                     showContactDetailsItem.setVisible(false);
+                    startSecrectChat.setVisible(false);
                 }
+
                 deleteContactMenuItem.setVisible(contact.showInRoster() && !contact.getOption(Contact.Options.SYNCED_VIA_OTHER));
                 final XmppConnection xmpp = contact.getAccount().getXmppConnection();
                 if (xmpp != null && xmpp.getFeatures().blocking() && !contact.isSelf()) {
@@ -1492,6 +1510,8 @@ public class StartConversationActivity extends XmppActivity implements XmppConne
                     break;
                 case R.id.context_delete_conference:
                     activity.deleteConference();
+                case R.id.context_contact_start_secrect_chat:
+                    activity.startOtrChat();
             }
             return true;
         }

src/main/java/eu/siacs/conversations/ui/VerifyOTRActivity.java

@@ -0,0 +1,450 @@
+package eu.siacs.conversations.ui;
+
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.os.Bundle;
+import android.util.Log;
+import android.view.Menu;
+import android.view.View;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AlertDialog;
+
+import net.java.otr4j.OtrException;
+import net.java.otr4j.session.Session;
+
+import eu.siacs.conversations.Config;
+import eu.siacs.conversations.R;
+import eu.siacs.conversations.entities.Account;
+import eu.siacs.conversations.entities.Contact;
+import eu.siacs.conversations.entities.Conversation;
+import eu.siacs.conversations.services.XmppConnectionService;
+import eu.siacs.conversations.utils.CryptoHelper;
+import eu.siacs.conversations.utils.XmppUri;
+import eu.siacs.conversations.xmpp.Jid;
+import me.drakeet.support.toast.ToastCompat;
+
+public class VerifyOTRActivity extends XmppActivity implements XmppConnectionService.OnConversationUpdate {
+
+    public static final String ACTION_VERIFY_CONTACT = "verify_contact";
+    public static final int MODE_SCAN_FINGERPRINT = -0x0502;
+    public static final int MODE_ASK_QUESTION = 0x0503;
+    public static final int MODE_ANSWER_QUESTION = 0x0504;
+    public static final int MODE_MANUAL_VERIFICATION = 0x0505;
+
+    private LinearLayout mManualVerificationArea;
+    private LinearLayout mSmpVerificationArea;
+    private TextView mRemoteFingerprint;
+    private TextView mYourFingerprint;
+    private TextView mVerificationExplain;
+    private TextView mStatusMessage;
+    private TextView mSharedSecretHint;
+    private EditText mSharedSecretHintEditable;
+    private EditText mSharedSecretSecret;
+    private Button mLeftButton;
+    private Button mRightButton;
+    private Account mAccount;
+    private Conversation mConversation;
+    private int mode = MODE_MANUAL_VERIFICATION;
+    private XmppUri mPendingUri = null;
+
+    private DialogInterface.OnClickListener mVerifyFingerprintListener = new DialogInterface.OnClickListener() {
+
+        @Override
+        public void onClick(DialogInterface dialogInterface, int click) {
+            mConversation.verifyOtrFingerprint();
+            xmppConnectionService.syncRosterToDisk(mConversation.getAccount());
+            ToastCompat.makeText(VerifyOTRActivity.this, R.string.verified, Toast.LENGTH_SHORT).show();
+            finish();
+        }
+    };
+
+    private View.OnClickListener mCreateSharedSecretListener = new View.OnClickListener() {
+        @Override
+        public void onClick(final View view) {
+            if (isAccountOnline()) {
+                final String question = mSharedSecretHintEditable.getText().toString();
+                final String secret = mSharedSecretSecret.getText().toString();
+                if (question.trim().isEmpty()) {
+                    mSharedSecretHintEditable.requestFocus();
+                    mSharedSecretHintEditable.setError(getString(R.string.shared_secret_hint_should_not_be_empty));
+                } else if (secret.trim().isEmpty()) {
+                    mSharedSecretSecret.requestFocus();
+                    mSharedSecretSecret.setError(getString(R.string.shared_secret_can_not_be_empty));
+                } else {
+                    mSharedSecretSecret.setError(null);
+                    mSharedSecretHintEditable.setError(null);
+                    initSmp(question, secret);
+                    updateView();
+                }
+            }
+        }
+    };
+    private View.OnClickListener mCancelSharedSecretListener = new View.OnClickListener() {
+        @Override
+        public void onClick(View view) {
+            if (isAccountOnline()) {
+                abortSmp();
+                updateView();
+            }
+        }
+    };
+    private View.OnClickListener mRespondSharedSecretListener = new View.OnClickListener() {
+
+        @Override
+        public void onClick(View view) {
+            if (isAccountOnline()) {
+                final String question = mSharedSecretHintEditable.getText().toString();
+                final String secret = mSharedSecretSecret.getText().toString();
+                respondSmp(question, secret);
+                updateView();
+            }
+        }
+    };
+    private View.OnClickListener mRetrySharedSecretListener = new View.OnClickListener() {
+        @Override
+        public void onClick(View view) {
+            mConversation.smp().status = Conversation.Smp.STATUS_NONE;
+            mConversation.smp().hint = null;
+            mConversation.smp().secret = null;
+            updateView();
+        }
+    };
+    private View.OnClickListener mFinishListener = new View.OnClickListener() {
+        @Override
+        public void onClick(View view) {
+            mConversation.smp().status = Conversation.Smp.STATUS_NONE;
+            finish();
+        }
+    };
+
+    protected boolean initSmp(final String question, final String secret) {
+        final Session session = mConversation.getOtrSession();
+        if (session != null) {
+            try {
+                session.initSmp(question, secret);
+                mConversation.smp().status = Conversation.Smp.STATUS_WE_REQUESTED;
+                mConversation.smp().secret = secret;
+                mConversation.smp().hint = question;
+                return true;
+            } catch (OtrException e) {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    protected boolean abortSmp() {
+        final Session session = mConversation.getOtrSession();
+        if (session != null) {
+            try {
+                session.abortSmp();
+                mConversation.smp().status = Conversation.Smp.STATUS_NONE;
+                mConversation.smp().hint = null;
+                mConversation.smp().secret = null;
+                return true;
+            } catch (OtrException e) {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    protected boolean respondSmp(final String question, final String secret) {
+        final Session session = mConversation.getOtrSession();
+        if (session != null) {
+            try {
+                session.respondSmp(question, secret);
+                return true;
+            } catch (OtrException e) {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    protected boolean verifyWithUri(XmppUri uri) {
+        Contact contact = mConversation.getContact();
+        if (this.mConversation.getContact().getJid().equals(uri.getJid()) && uri.hasFingerprints()) {
+            xmppConnectionService.verifyFingerprints(contact, uri.getFingerprints());
+            ToastCompat.makeText(this, R.string.verified, Toast.LENGTH_SHORT).show();
+            updateView();
+            return true;
+        } else {
+            ToastCompat.makeText(this, R.string.could_not_verify_fingerprint, Toast.LENGTH_SHORT).show();
+            return false;
+        }
+    }
+
+    protected boolean isAccountOnline() {
+        if (this.mAccount.getStatus() != Account.State.ONLINE) {
+            ToastCompat.makeText(this, R.string.not_connected_try_again, Toast.LENGTH_SHORT).show();
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    protected boolean handleIntent(Intent intent) {
+        if (intent != null && intent.getAction().equals(ACTION_VERIFY_CONTACT)) {
+            this.mAccount = extractAccount(intent);
+            if (this.mAccount == null) {
+                return false;
+            }
+            try {
+                this.mConversation = this.xmppConnectionService.find(this.mAccount, Jid.of(intent.getExtras().getString("contact")), Jid.of(intent.getExtras().getString("counterpart")));
+                if (this.mConversation == null) {
+                    return false;
+                }
+            } catch (final IllegalArgumentException ignored) {
+                ignored.printStackTrace();
+                return false;
+            } catch (Exception e) {
+                e.printStackTrace();
+                return false;
+            }
+            this.mode = intent.getIntExtra("mode", MODE_MANUAL_VERIFICATION);
+            // todo scan OTR fingerprint
+            if (this.mode == MODE_SCAN_FINGERPRINT) {
+                Log.d(Config.LOGTAG, "Scan OTR fingerprint is not implemented in this version");
+                //new IntentIntegrator(this).initiateScan();
+                return false;
+            }
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent intent) {
+        // todo onActivityResult for OTR scan
+        Log.d(Config.LOGTAG, "Scan OTR fingerprint result is not implemented in this version");
+        /*if ((requestCode & 0xFFFF) == IntentIntegrator.REQUEST_CODE) {
+            IntentResult scanResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, intent);
+            if (scanResult != null && scanResult.getFormatName() != null) {
+                String data = scanResult.getContents();
+                XmppUri uri = new XmppUri(data);
+                if (xmppConnectionServiceBound) {
+                    verifyWithUri(uri);
+                    finish();
+                } else {
+                    this.mPendingUri = uri;
+                }
+            } else {
+                finish();
+            }
+        }*/
+        super.onActivityResult(requestCode, requestCode, intent);
+    }
+
+    @Override
+    protected void onBackendConnected() {
+        if (handleIntent(getIntent())) {
+            updateView();
+        } else if (mPendingUri != null) {
+            verifyWithUri(mPendingUri);
+            finish();
+            mPendingUri = null;
+        }
+        setIntent(null);
+    }
+
+    protected void updateView() {
+        if (this.mConversation != null && this.mConversation.hasValidOtrSession()) {
+            final ActionBar actionBar = getSupportActionBar();
+            this.mVerificationExplain.setText(R.string.no_otr_session_found);
+            invalidateOptionsMenu();
+            switch (this.mode) {
+                case MODE_ASK_QUESTION:
+                    if (actionBar != null) {
+                        actionBar.setTitle(R.string.ask_question);
+                    }
+                    this.updateViewAskQuestion();
+                    break;
+                case MODE_ANSWER_QUESTION:
+                    if (actionBar != null) {
+                        actionBar.setTitle(R.string.smp_requested);
+                    }
+                    this.updateViewAnswerQuestion();
+                    break;
+                case MODE_MANUAL_VERIFICATION:
+                default:
+                    if (actionBar != null) {
+                        actionBar.setTitle(R.string.manually_verify);
+                    }
+                    this.updateViewManualVerification();
+                    break;
+            }
+        } else {
+            this.mManualVerificationArea.setVisibility(View.GONE);
+            this.mSmpVerificationArea.setVisibility(View.GONE);
+        }
+    }
+
+    protected void updateViewManualVerification() {
+        this.mVerificationExplain.setText(R.string.manual_verification_explanation);
+        this.mManualVerificationArea.setVisibility(View.VISIBLE);
+        this.mSmpVerificationArea.setVisibility(View.GONE);
+        this.mYourFingerprint.setText(CryptoHelper.prettifyFingerprint(this.mAccount.getOtrFingerprint()));
+        this.mRemoteFingerprint.setText(CryptoHelper.prettifyFingerprint(this.mConversation.getOtrFingerprint()));
+        if (this.mConversation.isOtrFingerprintVerified()) {
+            deactivateButton(this.mRightButton, R.string.verified);
+            activateButton(this.mLeftButton, R.string.cancel, this.mFinishListener);
+        } else {
+            activateButton(this.mLeftButton, R.string.cancel, this.mFinishListener);
+            activateButton(this.mRightButton, R.string.verify, new View.OnClickListener() {
+                @Override
+                public void onClick(View view) {
+                    showManuallyVerifyDialog();
+                }
+            });
+        }
+    }
+
+    protected void updateViewAskQuestion() {
+        this.mManualVerificationArea.setVisibility(View.GONE);
+        this.mSmpVerificationArea.setVisibility(View.VISIBLE);
+        this.mVerificationExplain.setText(R.string.smp_explain_question);
+        final int smpStatus = this.mConversation.smp().status;
+        switch (smpStatus) {
+            case Conversation.Smp.STATUS_WE_REQUESTED:
+                this.mStatusMessage.setVisibility(View.GONE);
+                this.mSharedSecretHintEditable.setVisibility(View.VISIBLE);
+                this.mSharedSecretSecret.setVisibility(View.VISIBLE);
+                this.mSharedSecretHintEditable.setText(this.mConversation.smp().hint);
+                this.mSharedSecretSecret.setText(this.mConversation.smp().secret);
+                this.activateButton(this.mLeftButton, R.string.cancel, this.mCancelSharedSecretListener);
+                this.deactivateButton(this.mRightButton, R.string.in_progress);
+                break;
+            case Conversation.Smp.STATUS_FAILED:
+                this.mStatusMessage.setVisibility(View.GONE);
+                this.mSharedSecretHintEditable.setVisibility(View.VISIBLE);
+                this.mSharedSecretSecret.setVisibility(View.VISIBLE);
+                this.mSharedSecretSecret.requestFocus();
+                this.mSharedSecretSecret.setError(getString(R.string.secrets_do_not_match));
+                this.deactivateButton(this.mLeftButton, R.string.cancel);
+                this.activateButton(this.mRightButton, R.string.try_again, this.mRetrySharedSecretListener);
+                break;
+            case Conversation.Smp.STATUS_VERIFIED:
+                this.mSharedSecretHintEditable.setText("");
+                this.mSharedSecretHintEditable.setVisibility(View.GONE);
+                this.mSharedSecretSecret.setText("");
+                this.mSharedSecretSecret.setVisibility(View.GONE);
+                this.mStatusMessage.setVisibility(View.VISIBLE);
+                this.deactivateButton(this.mLeftButton, R.string.cancel);
+                this.activateButton(this.mRightButton, R.string.finish, this.mFinishListener);
+                break;
+            default:
+                this.mStatusMessage.setVisibility(View.GONE);
+                this.mSharedSecretHintEditable.setVisibility(View.VISIBLE);
+                this.mSharedSecretSecret.setVisibility(View.VISIBLE);
+                this.activateButton(this.mLeftButton, R.string.cancel, this.mFinishListener);
+                this.activateButton(this.mRightButton, R.string.ask_question, this.mCreateSharedSecretListener);
+                break;
+        }
+    }
+
+    protected void updateViewAnswerQuestion() {
+        this.mManualVerificationArea.setVisibility(View.GONE);
+        this.mSmpVerificationArea.setVisibility(View.VISIBLE);
+        this.mVerificationExplain.setText(R.string.smp_explain_answer);
+        this.mSharedSecretHintEditable.setVisibility(View.GONE);
+        this.mSharedSecretHint.setVisibility(View.VISIBLE);
+        this.deactivateButton(this.mLeftButton, R.string.cancel);
+        final int smpStatus = this.mConversation.smp().status;
+        switch (smpStatus) {
+            case Conversation.Smp.STATUS_CONTACT_REQUESTED:
+                this.mStatusMessage.setVisibility(View.GONE);
+                this.mSharedSecretHint.setText(this.mConversation.smp().hint);
+                this.activateButton(this.mRightButton, R.string.respond, this.mRespondSharedSecretListener);
+                break;
+            case Conversation.Smp.STATUS_VERIFIED:
+                this.mSharedSecretHintEditable.setText("");
+                this.mSharedSecretHintEditable.setVisibility(View.GONE);
+                this.mSharedSecretHint.setVisibility(View.GONE);
+                this.mSharedSecretSecret.setText("");
+                this.mSharedSecretSecret.setVisibility(View.GONE);
+                this.mStatusMessage.setVisibility(View.VISIBLE);
+                this.activateButton(this.mRightButton, R.string.finish, this.mFinishListener);
+                break;
+            case Conversation.Smp.STATUS_FAILED:
+            default:
+                this.mSharedSecretSecret.requestFocus();
+                this.mSharedSecretSecret.setError(getString(R.string.secrets_do_not_match));
+                this.activateButton(this.mRightButton, R.string.finish, this.mFinishListener);
+                break;
+        }
+    }
+
+    protected void activateButton(Button button, int text, View.OnClickListener listener) {
+        button.setEnabled(true);
+        button.setText(text);
+        button.setOnClickListener(listener);
+    }
+
+    protected void deactivateButton(Button button, int text) {
+        button.setEnabled(false);
+        button.setText(text);
+        button.setOnClickListener(null);
+    }
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_verify_otr);
+        this.mRemoteFingerprint = findViewById(R.id.remote_fingerprint);
+        this.mYourFingerprint = findViewById(R.id.your_fingerprint);
+        this.mLeftButton = findViewById(R.id.left_button);
+        this.mRightButton = findViewById(R.id.right_button);
+        this.mVerificationExplain = findViewById(R.id.verification_explanation);
+        this.mStatusMessage = findViewById(R.id.status_message);
+        this.mSharedSecretSecret = findViewById(R.id.shared_secret_secret);
+        this.mSharedSecretHintEditable = findViewById(R.id.shared_secret_hint_editable);
+        this.mSharedSecretHint = findViewById(R.id.shared_secret_hint);
+        this.mManualVerificationArea = findViewById(R.id.manual_verification_area);
+        this.mSmpVerificationArea = findViewById(R.id.smp_verification_area);
+    }
+
+    @Override
+    public boolean onCreateOptionsMenu(final Menu menu) {
+        super.onCreateOptionsMenu(menu);
+        getMenuInflater().inflate(R.menu.verify_otr, menu);
+        return true;
+    }
+
+    private void showManuallyVerifyDialog() {
+        final AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setTitle(R.string.manually_verify);
+        builder.setMessage(R.string.are_you_sure_verify_fingerprint);
+        builder.setNegativeButton(R.string.cancel, null);
+        builder.setPositiveButton(R.string.verify, mVerifyFingerprintListener);
+        builder.create().show();
+    }
+
+    @Override
+    protected String getShareableUri() {
+        if (mAccount != null) {
+            return mAccount.getShareableUri();
+        } else {
+            return "";
+        }
+    }
+
+    public void onConversationUpdate() {
+        refreshUi();
+    }
+
+    @Override
+    protected void refreshUiReal() {
+        updateView();
+    }
+}

src/main/java/eu/siacs/conversations/ui/XmppActivity.java

@@ -56,6 +56,8 @@ import androidx.databinding.DataBindingUtil;
 
 import com.google.common.base.Strings;
 
+import net.java.otr4j.session.SessionID;
+
 import java.io.IOException;
 import java.lang.ref.WeakReference;
 import java.util.ArrayList;
@@ -446,7 +448,18 @@ public abstract class XmppActivity extends ActionBarActivity {
 
     public void selectPresence(final Conversation conversation, final PresenceSelector.OnPresenceSelected listener) {
         final Contact contact = conversation.getContact();
-        if (contact.showInRoster() || contact.isSelf()) {
+
+        if (conversation.hasValidOtrSession()) {
+            SessionID id = conversation.getOtrSession().getSessionID();
+            Jid jid;
+            try {
+                jid = Jid.of(id.getAccountID() + "/" + id.getUserID());
+            } catch (IllegalArgumentException e) {
+                jid = null;
+            }
+            conversation.setNextCounterpart(jid);
+            listener.onPresenceSelected();
+        } else if (contact.showInRoster() || contact.isSelf()) {
             final Presences presences = contact.getPresences();
             if (presences.size() == 0) {
                 if (contact.isSelf()) {

src/main/java/eu/siacs/conversations/ui/adapter/AccountAdapter.java

@@ -9,6 +9,11 @@ import android.widget.ArrayAdapter;
 import androidx.annotation.NonNull;
 import androidx.databinding.DataBindingUtil;
 
+import com.kizitonwose.colorpreference.ColorDialog;
+import com.kizitonwose.colorpreference.ColorPreference;
+import com.kizitonwose.colorpreference.ColorShape;
+import com.kizitonwose.colorpreference.ColorUtils;
+
 import java.util.List;
 
 import eu.siacs.conversations.Config;
@@ -19,22 +24,29 @@ import eu.siacs.conversations.ui.XmppActivity;
 import eu.siacs.conversations.ui.util.AvatarWorkerTask;
 import eu.siacs.conversations.ui.util.StyledAttributes;
 import eu.siacs.conversations.utils.UIHelper;
+import eu.siacs.conversations.xmpp.Jid;
 
 public class AccountAdapter extends ArrayAdapter<Account> {
 
     private final XmppActivity activity;
     private final boolean showStateButton;
+    private final boolean showColorSelector;
+
+    public ColorSelectorListener colorSelectorListener = null;
 
     public AccountAdapter(XmppActivity activity, List<Account> objects, boolean showStateButton) {
         super(activity, 0, objects);
         this.activity = activity;
         this.showStateButton = showStateButton;
+        this.showColorSelector = false;
     }
 
-    public AccountAdapter(XmppActivity activity, List<Account> objects) {
+    public AccountAdapter(XmppActivity activity, List<Account> objects, ColorSelectorListener listener) {
         super(activity, 0, objects);
         this.activity = activity;
         this.showStateButton = true;
+        this.showColorSelector = true;
+        colorSelectorListener = listener;
     }
 
     @Override
@@ -77,18 +89,28 @@ public class AccountAdapter extends ArrayAdapter<Account> {
         } else {
             viewHolder.binding.tglAccountStatus.setVisibility(View.GONE);
         }
+
         viewHolder.binding.tglAccountStatus.setOnCheckedChangeListener((compoundButton, b) -> {
             if (b == isDisabled && activity instanceof OnTglAccountState) {
                 ((OnTglAccountState) activity).onClickTglAccountState(account, b);
             }
         });
 
-        if (activity.xmppConnectionService.getAccounts().size() > 1) {
-            viewHolder.binding.accountIndicator.setBackgroundColor(UIHelper.getColorForName(account.getJid().asBareJid().getEscapedLocal()));
+        if (this.showColorSelector && activity.xmppConnectionService.getAccounts().size() > 1 &&
+                activity.xmppConnectionService.getPreferences().getBoolean("show_account_indicator", activity.getResources().getBoolean(R.bool.show_account_indicator))) {
+            int color = UIHelper.getAccountColor(activity, account.getJid());
+            viewHolder.binding.colorView.setVisibility(View.VISIBLE);
+            ColorUtils.setColorViewValue(viewHolder.binding.colorView, color, false, ColorShape.CIRCLE);
+            viewHolder.binding.colorView.setOnClickListener(v -> {
+                if (colorSelectorListener != null) {
+                    colorSelectorListener.onColorPickerRequested(account.getJid(), color);
+                }
+            });
         } else {
-            viewHolder.binding.accountIndicator.setBackgroundColor(Color.TRANSPARENT);
+            viewHolder.binding.colorView.setVisibility(View.GONE);
         }
 
+
         return view;
     }
 
@@ -106,4 +128,7 @@ public class AccountAdapter extends ArrayAdapter<Account> {
         void onClickTglAccountState(Account account, boolean state);
     }
 
+    public interface ColorSelectorListener {
+        void onColorPickerRequested(Jid accountJid, int currentColor);
+    }
 }

src/main/java/eu/siacs/conversations/ui/adapter/ConversationAdapter.java

@@ -338,8 +338,12 @@ public class ConversationAdapter
         }
 
         CharSequence name = conversation.getName();
-        if (conversation.getNextCounterpart() != null) {
-            name = viewHolder.binding.getRoot().getResources().getString(R.string.muc_private_conversation_title, conversation.getNextCounterpart().getResource(), conversation.getName());
+        if (conversation.getNextCounterpart() != null && conversation.hasPermanentCounterpart()) {
+            if (conversation.getMode() == Conversational.MODE_MULTI) {
+                name = viewHolder.binding.getRoot().getResources().getString(R.string.muc_private_conversation_title, conversation.getNextCounterpart().getResource(), conversation.getName());
+            } else {
+                name = viewHolder.binding.getRoot().getResources().getString(R.string.secret_chat_title, conversation.getName(), conversation.getNextCounterpart().getResource());
+            }
         }
 
         if  (conversation.withSelf()) {
@@ -386,6 +390,10 @@ public class ConversationAdapter
             int drId = activity.getThemeResource(R.attr.ic_group_16, R.drawable.ic_group_selected_black_16);
             Drawable dr = AppCompatResources.getDrawable(activity, drId);
             viewHolder.binding.conversationName.setCompoundDrawablesRelativeWithIntrinsicBounds(null, null, dr, null);
+        } else if (conversation.getMode() == Conversation.MODE_SINGLE && conversation.hasPermanentCounterpart()) {
+            int drId = activity.getThemeResource(R.attr.ic_secret_chat_16, R.drawable.ic_secret_chat_16dp_black);
+            Drawable dr = AppCompatResources.getDrawable(activity, drId);
+            viewHolder.binding.conversationName.setCompoundDrawablesRelativeWithIntrinsicBounds(null, null, dr, null);
         } else {
             viewHolder.binding.conversationName.setCompoundDrawablesRelativeWithIntrinsicBounds(null, null, null, null);
         }
@@ -393,7 +401,7 @@ public class ConversationAdapter
         Contact contact = conversation.getContact();
 
         if (contact != null) {
-            viewHolder.binding.presenceIndicator.setStatus(contact.getShownStatus());
+            viewHolder.binding.presenceIndicator.setStatus(contact);
         } else {
             viewHolder.binding.presenceIndicator.setStatus(null);
         }
@@ -401,7 +409,7 @@ public class ConversationAdapter
         Account account = conversation.getAccount();
 
         if (account != null && activity.xmppConnectionService.getAccounts().size() > 1) {
-            viewHolder.binding.accountIndicator.setBackgroundColor(UIHelper.getColorForName(account.getJid().asBareJid().getEscapedLocal()));
+            viewHolder.binding.accountIndicator.setBackgroundColor(UIHelper.getAccountColor(activity, account.getJid()));
         } else {
             viewHolder.binding.accountIndicator.setBackgroundColor(Color.TRANSPARENT);
         }

src/main/java/eu/siacs/conversations/ui/adapter/ListItemAdapter.java

@@ -94,7 +94,7 @@ public class ListItemAdapter extends ArrayAdapter<ListItem> {
 		AvatarWorkerTask.loadAvatar(item, viewHolder.avatar, R.dimen.avatar);
 
 		if (item instanceof Contact) {
-			viewHolder.presenceIndicator.setStatus(((Contact) item).getShownStatus());
+			viewHolder.presenceIndicator.setStatus(((Contact) item));
 		} else {
 			viewHolder.presenceIndicator.setStatus(null);
 		}
@@ -108,7 +108,7 @@ public class ListItemAdapter extends ArrayAdapter<ListItem> {
 		}
 
 		if (account != null && activity.xmppConnectionService.getAccounts().size() > 1) {
-			viewHolder.accountIndicator.setBackgroundColor(UIHelper.getColorForName(account.getJid().asBareJid().getEscapedLocal()));
+			viewHolder.accountIndicator.setBackgroundColor(UIHelper.getAccountColor(activity, account.getJid()));
 		} else {
 			viewHolder.accountIndicator.setBackgroundColor(Color.TRANSPARENT);
 		}

src/main/java/eu/siacs/conversations/ui/adapter/UserAdapter.java

@@ -91,7 +91,7 @@ public class UserAdapter extends ListAdapter<MucOptions.User, UserAdapter.ViewHo
             } else {
                 viewHolder.binding.contactJid.setText(ConferenceDetailsActivity.getStatus(viewHolder.binding.getRoot().getContext(), user, advancedMode));
             }
-            viewHolder.binding.presenceIndicator.setStatus(contact.getShownStatus());
+            viewHolder.binding.presenceIndicator.setStatus(contact);
         } else {
             viewHolder.binding.contactDisplayName.setText(name == null ? "" : name);
             viewHolder.binding.contactJid.setText(ConferenceDetailsActivity.getStatus(viewHolder.binding.getRoot().getContext(), user, advancedMode));

src/main/java/eu/siacs/conversations/ui/adapter/UserPreviewAdapter.java

@@ -38,7 +38,7 @@ public class UserPreviewAdapter extends ListAdapter<MucOptions.User, UserPreview
         AvatarWorkerTask.loadAvatar(user, viewHolder.binding.avatar, R.dimen.media_size);
         Contact contact = user.getContact();
         if (contact != null) {
-            viewHolder.binding.presenceIndicator.setStatus(user.getContact().getShownStatus());
+            viewHolder.binding.presenceIndicator.setStatus(user.getContact());
         } else {
             viewHolder.binding.presenceIndicator.setStatus(null);
         }

src/main/java/eu/siacs/conversations/ui/widget/AccountIndicator.kt

@@ -0,0 +1,37 @@
+package eu.siacs.conversations.ui.widget
+
+import android.content.Context
+import android.util.AttributeSet
+import android.view.View
+import eu.siacs.conversations.R
+import eu.siacs.conversations.ui.XmppActivity
+
+class AccountIndicator : View {
+    constructor(context: Context?) : super(context)
+    constructor(context: Context?, attrs: AttributeSet?) : super(context, attrs)
+    constructor(context: Context?, attrs: AttributeSet?, defStyleAttr: Int) : super(
+        context,
+        attrs,
+        defStyleAttr
+    )
+
+    constructor(
+        context: Context?,
+        attrs: AttributeSet?,
+        defStyleAttr: Int,
+        defStyleRes: Int
+    ) : super(context, attrs, defStyleAttr, defStyleRes)
+
+    override fun onAttachedToWindow() {
+        super.onAttachedToWindow()
+        val enabled = (context as? XmppActivity)
+            ?.xmppConnectionService?.preferences
+            ?.getBoolean("show_account_indicator", context.resources.getBoolean(R.bool.show_account_indicator)) ?: false
+
+        visibility = if (enabled) {
+            VISIBLE
+        } else {
+            INVISIBLE
+        }
+    }
+}

src/main/java/eu/siacs/conversations/ui/widget/PresenceIndicator.kt

@@ -8,9 +8,13 @@ import android.graphics.Paint
 import android.util.AttributeSet
 import android.view.View
 import android.view.ViewOutlineProvider
+import eu.siacs.conversations.R
+import eu.siacs.conversations.entities.Contact
 import eu.siacs.conversations.entities.Presence
+import eu.siacs.conversations.ui.XmppActivity
 import eu.siacs.conversations.ui.util.StyledAttributes
 import eu.siacs.conversations.utils.UIHelper
+import eu.siacs.conversations.xml.Namespace
 
 class PresenceIndicator : View {
     private var paint: Paint = Paint().also {
@@ -19,13 +23,9 @@ class PresenceIndicator : View {
         it.strokeWidth = 1 * Resources.getSystem().displayMetrics.density
     }
 
-    var status: Presence.Status? = null
-        set(value) {
-            if (field != value) {
-                field = value
-                invalidate()
-            }
-        }
+    private var status: Presence.Status? = null
+
+    private var enabled = false
 
     constructor(context: Context?) : super(context)
     constructor(context: Context?, attrs: AttributeSet?) : super(context, attrs)
@@ -51,7 +51,28 @@ class PresenceIndicator : View {
         }
     }
 
+    fun setStatus(contact: Contact?) {
+        val status = contact?.shownStatus?.takeIf {
+            contact.account?.isOnlineAndConnected == true
+        }
+        if (status != this.status) {
+            this.status = status
+            invalidate()
+        }
+    }
+
+    override fun onAttachedToWindow() {
+        super.onAttachedToWindow()
+        enabled = (context as? XmppActivity)
+            ?.xmppConnectionService?.preferences
+            ?.getBoolean("show_contact_status", context.resources.getBoolean(R.bool.show_contact_status)) ?: false
+    }
+
     override fun onDraw(canvas: Canvas) {
+        if (!enabled) {
+            return
+        }
+
         super.onDraw(canvas)
 
         val color: Int? = UIHelper.getColorForStatus(status);

src/main/java/eu/siacs/conversations/utils/CryptoHelper.java

@@ -41,6 +41,7 @@ public final class CryptoHelper {
     private static final int PW_LENGTH = 12;
     private static final char[] VOWELS = "aeiou".toCharArray();
     private static final char[] CONSONANTS = "bcfghjklmnpqrstvwxyz".toCharArray();
+    public static final String FILETRANSFER = "?FILETRANSFERv1:";
     private final static char[] hexArray = "0123456789abcdef".toCharArray();
 
     public static String bytesToHex(byte[] bytes) {

src/main/java/eu/siacs/conversations/utils/UIHelper.java

@@ -1,6 +1,7 @@
 package eu.siacs.conversations.utils;
 
 import android.content.Context;
+import android.content.SharedPreferences;
 import android.text.SpannableStringBuilder;
 import android.text.format.DateFormat;
 import android.text.format.DateUtils;
@@ -204,26 +205,60 @@ public class UIHelper {
                 .get(Calendar.DAY_OF_YEAR);
     }
 
-    public static String lastseen(Context context, boolean active, long time) {
+    public static String lastseen(Context context, boolean active, long time, boolean shortText) {
         long difference = (System.currentTimeMillis() - time) / 1000;
         if (active) {
-            return context.getString(R.string.online_right_now);
+            if (shortText) {
+                return context.getString(R.string.online_right_now_short);
+            } else {
+                return context.getString(R.string.online_right_now);
+            }
         } else if (difference < 60) {
-            return context.getString(R.string.last_seen_now);
+            if (shortText) {
+                return context.getString(R.string.last_seen_now_short);
+            } else {
+                return context.getString(R.string.last_seen_now);
+            }
         } else if (difference < 60 * 2) {
-            return context.getString(R.string.last_seen_min);
+            if (shortText) {
+                return context.getString(R.string.last_seen_min_short);
+            } else {
+                return context.getString(R.string.last_seen_min);
+            }
         } else if (difference < 60 * 60) {
-            return context.getString(R.string.last_seen_mins, Math.round(difference / 60.0));
+            if (shortText) {
+                return context.getString(R.string.last_seen_mins_short, Math.round(difference / 60.0));
+            } else {
+                return context.getString(R.string.last_seen_mins, Math.round(difference / 60.0));
+            }
         } else if (difference < 60 * 60 * 2) {
-            return context.getString(R.string.last_seen_hour);
+            if (shortText) {
+                return context.getString(R.string.last_seen_hour_short);
+            } else {
+                return context.getString(R.string.last_seen_hour);
+            }
         } else if (difference < 60 * 60 * 24) {
-            return context.getString(R.string.last_seen_hours,
-                    Math.round(difference / (60.0 * 60.0)));
+            if (shortText) {
+                return context.getString(R.string.last_seen_hours_short,
+                        Math.round(difference / (60.0 * 60.0)));
+            } else {
+                return context.getString(R.string.last_seen_hours,
+                        Math.round(difference / (60.0 * 60.0)));
+            }
         } else if (difference < 60 * 60 * 48) {
-            return context.getString(R.string.last_seen_day);
+            if (shortText) {
+                return context.getString(R.string.last_seen_day_short);
+            } else {
+                return context.getString(R.string.last_seen_day);
+            }
         } else {
-            return context.getString(R.string.last_seen_days,
-                    Math.round(difference / (60.0 * 60.0 * 24.0)));
+            if (shortText) {
+                return context.getString(R.string.last_seen_days_short,
+                        Math.round(difference / (60.0 * 60.0 * 24.0)));
+            } else {
+                return context.getString(R.string.last_seen_days,
+                        Math.round(difference / (60.0 * 60.0 * 24.0)));
+            }
         }
     }
 
@@ -231,6 +266,23 @@ public class UIHelper {
         return getColorForName(name, false);
     }
 
+    public static int getAccountColor(Context context, Jid accountJid) {
+        SharedPreferences prefs = context.getSharedPreferences("accountColorsPrefs", Context.MODE_PRIVATE);
+        String name = accountJid.asBareJid().toEscapedString();
+        int overrideColor = prefs.getInt(name, -1);
+
+        if (overrideColor != -1) {
+            return overrideColor;
+        } else {
+            return getColorForName(name);
+        }
+    }
+
+    public static void overrideAccountColor(Context context, String accountName, int color) {
+        SharedPreferences prefs = context.getSharedPreferences("accountColorsPrefs", Context.MODE_PRIVATE);
+        prefs.edit().putInt(accountName, color).apply();
+    }
+
     public static int getColorForName(String name, boolean safe) {
         if (Config.XEP_0392) {
             return XEP0392Helper.rgbFromNick(name);
@@ -292,6 +344,8 @@ public class UIHelper {
             return new Pair<>(context.getString(R.string.file_deleted), true);
         } else if (message.getEncryption() == Message.ENCRYPTION_PGP) {
             return new Pair<>(context.getString(R.string.pgp_message), true);
+        } else if (message.getEncryption() == Message.ENCRYPTION_OTR) {
+            return new Pair<>(context.getString(R.string.otr_message), true);
         } else if (message.getEncryption() == Message.ENCRYPTION_DECRYPTION_FAILED) {
             return new Pair<>(context.getString(R.string.decryption_failed), true);
         } else if (message.getEncryption() == Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE) {
@@ -557,6 +611,8 @@ public class UIHelper {
                 } else {
                     return context.getString(R.string.send_message_to_x, conversation.getName());
                 }
+            case Message.ENCRYPTION_OTR:
+                return context.getString(R.string.send_otr_message);
             case Message.ENCRYPTION_AXOLOTL:
                 AxolotlService axolotlService = conversation.getAccount().getAxolotlService();
                 if (axolotlService != null && axolotlService.trustedSessionVerified(conversation)) {

src/main/java/eu/siacs/conversations/utils/XmppUri.java

@@ -29,6 +29,7 @@ public class XmppUri {
     public static final String PARAMETER_PRE_AUTH = "preauth";
     public static final String PARAMETER_IBR = "ibr";
     private static final String OMEMO_URI_PARAM = "omemo-sid-";
+    private static final String OTR_URI_PARAM = "otr-fingerprint";
     protected Uri uri;
     protected String jid;
     private List<Fingerprint> fingerprints = new ArrayList<>();
@@ -111,6 +112,8 @@ public class XmppUri {
             if (type == XmppUri.FingerprintType.OMEMO) {
                 builder.append(XmppUri.OMEMO_URI_PARAM);
                 builder.append(fingerprints.get(i).deviceId);
+            } else if (type == XmppUri.FingerprintType.OTR) {
+                builder.append(XmppUri.OTR_URI_PARAM);
             }
             builder.append('=');
             builder.append(fingerprints.get(i).fingerprint);
@@ -241,7 +244,8 @@ public class XmppUri {
     }
 
     public enum FingerprintType {
-        OMEMO
+        OMEMO,
+        OTR
     }
 
     public static class Fingerprint {
@@ -249,6 +253,10 @@ public class XmppUri {
         public final String fingerprint;
         final int deviceId;
 
+        public Fingerprint(FingerprintType type, String fingerprint) {
+            this(type, fingerprint, 0);
+        }
+
         public Fingerprint(FingerprintType type, String fingerprint, int deviceId) {
             this.type = type;
             this.fingerprint = fingerprint;

src/main/java/eu/siacs/conversations/xmpp/jid/OtrJidHelper.java

@@ -0,0 +1,17 @@
+
+package eu.siacs.conversations.xmpp.jid;
+
+import net.java.otr4j.session.SessionID;
+
+import eu.siacs.conversations.xmpp.Jid;
+
+public final class OtrJidHelper {
+
+    public static Jid fromSessionID(final SessionID id) throws IllegalArgumentException {
+        if (id.getUserID().isEmpty()) {
+            return Jid.of(id.getAccountID());
+        } else {
+            return Jid.of(id.getAccountID() + "/" + id.getUserID());
+        }
+    }
+}

src/main/res/drawable/ic_secret_chat_16dp_black.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="16dp"
+    android:height="16dp"
+    android:viewportWidth="960"
+    android:viewportHeight="960">
+    <path
+        android:fillColor="#000000"
+        android:pathData="M263.72,864Q234,864 213,842.85Q192,821.7 192,792L192,408Q192,378.3 213.15,357.15Q234.3,336 264,336L288,336L288,240Q288,160.32 344.23,104.16Q400.45,48 480.23,48Q560,48 616,104.16Q672,160.32 672,240L672,336L696,336Q725.7,336 746.85,357.15Q768,378.3 768,408L768,792Q768,821.7 746.84,842.85Q725.68,864 695.96,864L263.72,864ZM264,792L696,792Q696,792 696,792Q696,792 696,792L696,408Q696,408 696,408Q696,408 696,408L264,408Q264,408 264,408Q264,408 264,408L264,792Q264,792 264,792Q264,792 264,792ZM480.21,672Q510,672 531,650.79Q552,629.58 552,599.79Q552,570 530.79,549Q509.58,528 479.79,528Q450,528 429,549.21Q408,570.42 408,600.21Q408,630 429.21,651Q450.42,672 480.21,672ZM360,336L600,336L600,240Q600,190 565,155Q530,120 480,120Q430,120 395,155Q360,190 360,240L360,336ZM264,792Q264,792 264,792Q264,792 264,792L264,408Q264,408 264,408Q264,408 264,408L264,408Q264,408 264,408Q264,408 264,408L264,792Q264,792 264,792Q264,792 264,792Z"/>
+</vector>

src/main/res/drawable/ic_secret_chat_16dp_white.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="16dp"
+    android:height="16dp"
+    android:viewportWidth="960"
+    android:viewportHeight="960">
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M263.72,864Q234,864 213,842.85Q192,821.7 192,792L192,408Q192,378.3 213.15,357.15Q234.3,336 264,336L288,336L288,240Q288,160.32 344.23,104.16Q400.45,48 480.23,48Q560,48 616,104.16Q672,160.32 672,240L672,336L696,336Q725.7,336 746.85,357.15Q768,378.3 768,408L768,792Q768,821.7 746.84,842.85Q725.68,864 695.96,864L263.72,864ZM264,792L696,792Q696,792 696,792Q696,792 696,792L696,408Q696,408 696,408Q696,408 696,408L264,408Q264,408 264,408Q264,408 264,408L264,792Q264,792 264,792Q264,792 264,792ZM480.21,672Q510,672 531,650.79Q552,629.58 552,599.79Q552,570 530.79,549Q509.58,528 479.79,528Q450,528 429,549.21Q408,570.42 408,600.21Q408,630 429.21,651Q450.42,672 480.21,672ZM360,336L600,336L600,240Q600,190 565,155Q530,120 480,120Q430,120 395,155Q360,190 360,240L360,336ZM264,792Q264,792 264,792Q264,792 264,792L264,408Q264,408 264,408Q264,408 264,408L264,408Q264,408 264,408Q264,408 264,408L264,792Q264,792 264,792Q264,792 264,792Z"/>
+</vector>

src/main/res/drawable/ic_subject_black.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="960"
+    android:viewportHeight="960">
+    <path
+        android:fillColor="#000000"
+        android:pathData="M160,760L160,680L560,680L560,760L160,760ZM160,600L160,520L800,520L800,600L160,600ZM160,440L160,360L800,360L800,440L160,440ZM160,280L160,200L800,200L800,280L160,280Z"/>
+</vector>

src/main/res/drawable/ic_subject_white.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="960"
+    android:viewportHeight="960">
+    <path
+        android:fillColor="#ffffff"
+        android:pathData="M160,760L160,680L560,680L560,760L160,760ZM160,600L160,520L800,520L800,600L160,600ZM160,440L160,360L800,360L800,440L160,440ZM160,280L160,200L800,200L800,280L160,280Z"/>
+</vector>

src/main/res/layout/account_row.xml

@@ -6,17 +6,10 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:background="?selectableItemBackground"
-        android:clipToPadding="false"
         android:paddingLeft="8dp"
         android:paddingBottom="8dp"
         android:paddingTop="8dp">
 
-        <View
-            android:id="@+id/account_indicator"
-            android:layout_width="@dimen/account_indicator_width"
-            android:layout_marginStart="-4dp"
-            android:layout_height="48dp" />
-
         <eu.siacs.conversations.ui.widget.AvatarView
             android:id="@+id/account_image"
             android:layout_width="48dp"
@@ -31,8 +24,8 @@
             android:layout_toEndOf="@+id/account_image"
             android:orientation="vertical"
             android:paddingLeft="@dimen/avatar_item_distance"
-            android:layout_toLeftOf="@+id/tgl_account_status"
-            android:layout_toStartOf="@+id/tgl_account_status">
+            android:layout_toLeftOf="@+id/controls"
+            android:layout_toStartOf="@+id/controls">
 
             <TextView
                 android:id="@+id/account_jid"
@@ -50,14 +43,31 @@
                 android:textAppearance="@style/TextAppearance.Conversations.Body2" />
         </LinearLayout>
 
-        <androidx.appcompat.widget.SwitchCompat
-            android:id="@+id/tgl_account_status"
+        <LinearLayout
+            android:id="@+id/controls"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_alignParentRight="true"
-            android:layout_centerVertical="true"
+            android:orientation="horizontal"
+            android:gravity="center_vertical"
             android:padding="16dp"
-            android:focusable="false" />
+            android:layout_alignParentRight="true"
+            android:layout_centerVertical="true">
+
+            <ImageView
+                android:id="@+id/color_view"
+                android:layout_width="32dp"
+                android:layout_height="32dp"
+                android:layout_gravity="center"
+                android:layout_marginEnd="12dp"
+                android:scaleType="fitXY" />
+
+            <androidx.appcompat.widget.SwitchCompat
+                android:id="@+id/tgl_account_status"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:focusable="false" />
+
+        </LinearLayout>
 
     </RelativeLayout>
 </layout>

src/main/res/layout/activity_verify_otr.xml

@@ -0,0 +1,148 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="?attr/color_background_tertiary">
+
+    <ScrollView
+        android:layout_width="fill_parent"
+        android:layout_height="fill_parent"
+        android:layout_above="@+id/button_bar">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_marginStart="@dimen/activity_horizontal_margin"
+            android:layout_marginLeft="@dimen/activity_horizontal_margin"
+            android:layout_marginTop="@dimen/activity_vertical_margin"
+            android:layout_marginEnd="@dimen/activity_horizontal_margin"
+            android:layout_marginRight="@dimen/activity_horizontal_margin"
+            android:layout_marginBottom="@dimen/activity_vertical_margin"
+            android:orientation="vertical">
+
+            <TextView
+                android:id="@+id/verification_explanation"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content" />
+
+            <LinearLayout
+                android:id="@+id/manual_verification_area"
+                android:layout_width="fill_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="16dp"
+                android:orientation="vertical">
+
+                <TextView
+                    android:id="@+id/your_fingerprint"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:fontFamily="monospace"
+                    android:textAppearance="@style/TextAppearance.Conversations.Body1"
+                    android:typeface="monospace" />
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="@string/your_fingerprint"
+                    android:textAppearance="@style/TextAppearance.Conversations.Caption" />
+
+                <TextView
+                    android:id="@+id/remote_fingerprint"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="20dp"
+                    android:fontFamily="monospace"
+                    android:textAppearance="@style/TextAppearance.Conversations.Body1"
+                    android:typeface="monospace" />
+
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginBottom="20dp"
+                    android:text="@string/remote_fingerprint"
+                    android:textAppearance="@style/TextAppearance.Conversations.Caption" />
+
+            </LinearLayout>
+
+            <LinearLayout
+                android:id="@+id/smp_verification_area"
+                android:layout_width="fill_parent"
+                android:layout_height="fill_parent"
+                android:layout_marginTop="16dp"
+                android:orientation="vertical">
+
+                <TextView
+                    android:id="@+id/status_message"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_gravity="center_horizontal"
+                    android:text="@string/verified"
+                    android:textAppearance="@style/TextAppearance.Conversations.Title"
+                    android:textStyle="bold"
+                    android:visibility="gone" />
+
+                <TextView
+                    android:id="@+id/shared_secret_hint"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginBottom="8dp"
+                    android:textAppearance="@style/TextAppearance.Conversations.Body1"
+                    android:textStyle="bold"
+                    android:visibility="gone" />
+
+                <eu.siacs.conversations.ui.widget.TextInputEditText
+                    android:id="@+id/shared_secret_hint_editable"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginBottom="8dp"
+                    android:hint="@string/shared_secret_hint"
+                    android:inputType="textAutoComplete"
+                    android:textAppearance="@style/TextAppearance.Conversations.Body1"
+                    android:textColorHint="?attr/colorAccent" />
+
+                <eu.siacs.conversations.ui.widget.TextInputEditText
+                    android:id="@+id/shared_secret_secret"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="8dp"
+                    android:hint="@string/shared_secret_secret"
+                    android:inputType="textPassword"
+                    android:textAppearance="@style/TextAppearance.Conversations.Body1"
+                    android:textColorHint="?attr/colorAccent" />
+            </LinearLayout>
+        </LinearLayout>
+    </ScrollView>
+
+    <LinearLayout
+        android:id="@+id/button_bar"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_alignParentStart="true"
+        android:layout_alignParentLeft="true"
+        android:layout_alignParentEnd="true"
+        android:layout_alignParentRight="true"
+        android:layout_alignParentBottom="true">
+
+        <Button
+            android:id="@+id/left_button"
+            style="@style/Widget.Conversations.Button.Borderless"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1" />
+
+        <View
+            android:layout_width="1dp"
+            android:layout_height="fill_parent"
+            android:layout_marginTop="7dp"
+            android:layout_marginBottom="7dp"
+            android:background="?attr/color_background_primary" />
+
+        <Button
+            android:id="@+id/right_button"
+            style="@style/Widget.Conversations.Button.Borderless"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1" />
+    </LinearLayout>
+
+</RelativeLayout>

src/main/res/layout/contact.xml

@@ -9,7 +9,7 @@
         android:clipToPadding="false"
         android:padding="@dimen/list_padding">
 
-        <View
+        <eu.siacs.conversations.ui.widget.AccountIndicator
             android:id="@+id/account_indicator"
             android:layout_width="@dimen/account_indicator_width"
             android:layout_marginStart="-4dp"

src/main/res/layout/conversation_list_row.xml

@@ -20,7 +20,7 @@
                 android:clipToPadding="false"
                 android:padding="8dp">
 
-                <View
+                <eu.siacs.conversations.ui.widget.AccountIndicator
                     android:id="@+id/account_indicator"
                     android:layout_width="@dimen/account_indicator_width"
                     android:layout_marginStart="-4dp"

src/main/res/layout/fragment_conversation.xml

@@ -54,7 +54,7 @@
                     <ImageView
                         android:layout_width="24dp"
                         android:layout_height="24dp"
-                        android:src="?attr/ic_pin"
+                        android:src="?attr/ic_subject"
                         android:layout_marginEnd="8dp"
                         />
 

src/main/res/layout/toolbar.xml

@@ -6,6 +6,8 @@
     android:minHeight="?attr/actionBarSize"
     android:elevation="@dimen/toolbar_elevation"
     android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
+    app:titleTextAppearance="@style/ToolbarTitleAppearance"
+    app:subtitleTextAppearance="@style/ToolbarSubtitleAppearance"
     app:popupTheme="?popupOverlayStyle"
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto" />

src/main/res/menu/contact_context.xml

@@ -4,6 +4,11 @@
     <item
         android:id="@+id/context_contact_details"
         android:title="@string/view_contact_details"/>
+
+    <item
+        android:id="@+id/context_contact_start_secrect_chat"
+        android:title="@string/action_start_secret_chat"/>
+
     <item
         android:id="@+id/context_show_qr"
         android:title="@string/show_qr_code"/>

src/main/res/menu/fragment_conversation.xml

@@ -121,6 +121,17 @@
         android:orderInCategory="60"
         android:title="@string/action_end_conversation"
         app:showAsAction="never" />
+    <item
+        android:id="@+id/action_start_secret_chat"
+        android:orderInCategory="65"
+        android:title="@string/action_start_secret_chat"
+        app:showAsAction="never" />
+
+    <item
+        android:id="@+id/action_destroy_secret_chat"
+        android:orderInCategory="66"
+        android:title="@string/action_destroy_secret_chat"
+        app:showAsAction="never" />
     <item
         android:orderInCategory="70"
         android:title="@string/more_options">

src/main/res/menu/verification_choices.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item
+        android:id="@+id/ask_question"
+        android:title="@string/ask_question" />
+
+    <item
+        android:id="@+id/manual_verification"
+        android:title="@string/manually_verify" />
+
+    <item
+        android:id="@+id/blind_trust"
+        android:title="@string/otr_blind_trust" />
+
+</menu>

src/main/res/menu/verify_otr.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <item
+        android:id="@+id/action_show_qr_code"
+        android:title="@string/show_qr_code"
+        app:showAsAction="never" />
+
+    <item
+        android:id="@+id/action_settings"
+        android:orderInCategory="100"
+        app:showAsAction="never"
+        android:title="@string/action_settings" />
+</menu>

src/main/res/values/about.xml

@@ -60,6 +60,7 @@
 			\n\nhttps://github.com/zxing/zxing\n(Apache License, Version 2.0)
 			\n\nhttps://github.com/osmdroid/osmdroid\n(Apache License, Version 2.0)
 		    \n\nhttps://git.singpolyma.net/cheogram-android\n(GPLv3)
+		    \n\nhttps://github.com/jitsi/otr4j\n(LGPL-3.0)
 			\n\n\nMaps
 			\n\nMaps by Open Street Map (https://www.openstreetmap.org). Copyright restrictions may apply.
 	</string>

src/main/res/values/attrs.xml

@@ -40,6 +40,7 @@
     <attr name="ic_send_voice_offline" format="reference" />
 
     <attr name="ic_pin" format="reference" />
+    <attr name="ic_subject" format="reference" />
     <attr name="ic_close" format="reference" />
     <attr name="ic_attach_camera" format="reference" />
     <attr name="ic_attach_videocam" format="reference" />
@@ -133,6 +134,7 @@
     <attr name="ic_group_unselected" format="reference" />
     <attr name="ic_group_selected" format="reference" />
     <attr name="ic_group_16" format="reference" />
+    <attr name="ic_secret_chat_16" format="reference" />
 
     <attr name="dialog_horizontal_padding" format="dimension" />
     <attr name="dialog_vertical_padding" format="dimension" />

src/main/res/values/defaults.xml

@@ -55,4 +55,6 @@
     <bool name="always_full_timestamps">false</bool>
     <bool name="skip_image_editor_screen">false</bool>
     <string name="avatar_shape">rounded_square</string>
+    <bool name="show_contact_status">true</bool>
+    <bool name="show_account_indicator">true</bool>
 </resources>

src/main/res/values/strings.xml

@@ -6,6 +6,8 @@
     <string name="action_accounts">Manage accounts</string>
     <string name="action_account">Manage account</string>
     <string name="action_end_conversation">Close conversation</string>
+    <string name="action_start_secret_chat">Start secret chat</string>
+    <string name="action_destroy_secret_chat">Destroy secret chat</string>
     <string name="action_contact_details">Contact details</string>
     <string name="action_muc_details">Group chat details</string>
     <string name="channel_details">Channel details</string>
@@ -38,6 +40,7 @@
     <string name="sending">sending…</string>
     <string name="message_decrypting">Decrypting message. Please wait…</string>
     <string name="pgp_message">OpenPGP encrypted message</string>
+    <string name="otr_message">Secret chat message</string>
     <string name="nick_in_use">Nickname is already in use</string>
     <string name="invalid_muc_nick">Invalid nickname</string>
     <string name="admin">Admin</string>
@@ -612,6 +615,10 @@
     <string name="pref_skip_image_editor_screen_summary">Don’t open image editor screen automatically for single image attachments</string>
     <string name="unable_to_connect_to_keychain">Could not connect to OpenKeychain</string>
     <string name="this_device_is_no_longer_in_use">This device is no longer in use</string>
+    <string name="pref_show_contact_presence">Contact presence</string>
+    <string name="pref_show_contact_presence_details">Show contact presence nearby contact avatar</string>
+    <string name="pref_show_account_indicator">Account indicator</string>
+    <string name="pref_show_account_indicator_details">Mark conversations with different colors in case of several account</string>
     <string name="type_pc">Computer</string>
     <string name="type_phone">Mobile phone</string>
     <string name="type_tablet">Tablet</string>
@@ -1085,6 +1092,8 @@
     <string name="resize">resize</string>
     <string name="filter">filter</string>
     <string name="could_not_create_file">could_not_create_file</string>
+    <string name="secret_chat_title">%1$s (Secret Chat / %2$s)</string>
+    <string name="secret_chat_title_no_resource">%1$s (Secret Chat)</string>
     <string name="muc_private_conversation_title">%1$s (%2$s)</string>
     <string name="note_to_self_conversation_title">Note to self (%1$s)</string>
     <string name="muc_private_conversation_info_title">Private conversation with:</string>
@@ -1108,6 +1117,19 @@
     <string name="avater_shape_rounded_square">Rounded Square</string>
     <string name="avater_shape_square">Square</string>
 
+    <plurals name="x_participants">
+        <item quantity="one">%1$d participant</item>
+        <item quantity="other">%1$d participants</item>
+    </plurals>
+
+    <string name="online_right_now_short">online</string>
+    <string name="last_seen_now_short">just now</string>
+    <string name="last_seen_min_short">one minute ago</string>
+    <string name="last_seen_mins_short">%d minutes ago</string>
+    <string name="last_seen_hour_short">one hour ago</string>
+    <string name="last_seen_hours_short">%d hours ago</string>
+    <string name="last_seen_day_short">one day ago</string>
+    <string name="last_seen_days_short">%d days ago</string>
 
     <string name="clarendon" translatable="false">Clarendon</string>
     <string name="oldman" translatable="false">OldMan</string>
@@ -1125,4 +1147,39 @@
     <string name="struck" translatable="false">Struck</string>
     <string name="whisper" translatable="false">Whisper</string>
     <string name="lime" translatable="false">Lime</string>
+
+    <string name="send_otr_message">Write message…</string>
+    <string name="unknown_otr_fingerprint">Unknown OTR fingerprint</string>
+    <string name="otr_fingerprint">OTR fingerprint</string>
+    <string name="otr_fingerprint_selected_message">OTR fingerprint of message</string>
+    <string name="toast_message_otr_fingerprint">OTR fingerprint copied to clipboard!</string>
+    <string name="verify_otr">Verify OTR</string>
+    <string name="no_otr_session_found">No valid OTR session has been found!</string>
+    <string name="are_you_sure_verify_fingerprint">Are you sure that you want to verify your contacts OTR fingerprint?</string>
+    <string name="copy_otr_clipboard_description">Copy OTR fingerprint to clipboard</string>
+    <string name="otr_session_not_started">Send a message to start an encrypted chat</string>
+    <string name="pref_enable_otr_summary">Enable OTR encryption for message encryption. OTR is still highly unstable, please only use it if you know what you do.</string>
+    <string name="pref_enable_otr">Enable OTR encryption (BETA)</string>
+    <string name="otr_warning">The support of OTR encryption is in the beta mode. Click read more to get more information. A link in a browser will open.</string>
+    <string name="verified">Verified!</string>
+    <string name="smp_requested">Contact requested SMP verification</string>
+    <string name="smp_explain_question">If you and your contact have a secret in common that no one else knows (like an inside joke or simply what you had for lunch the last time you met) you can use that secret to verify each other’s fingerprints.\n\nYou provide a hint or a question for your contact who will respond with a case-sensitive answer.</string>
+    <string name="smp_explain_answer">Your contact would like to verify your fingerprint by challenging you with a shared secret. Your contact provided the following hint or question for that secret.</string>
+    <string name="shared_secret_hint_should_not_be_empty">Your hint should not be empty</string>
+    <string name="shared_secret_can_not_be_empty">Your shared secret can not be empty</string>
+    <string name="manual_verification_explanation">Carefully compare the fingerprint shown below with the fingerprint of your contact.\nYou can use any trusted form of communication like an encrypted e-mail or a telephone call to exchange those.</string>
+    <string name="could_not_verify_fingerprint">Could not verify fingerprint</string>
+    <string name="manually_verify">Manually verify</string>
+    <string name="otr_blind_trust">Blind trust</string>
+    <string name="secrets_do_not_match">Secrets do not match</string>
+    <string name="ask_question">Ask question</string>
+    <string name="verify">Verify</string>
+    <string name="in_progress">In progress</string>
+    <string name="respond">Respond</string>
+    <string name="failed">Failed</string>
+    <string name="finish">Finish</string>
+    <string name="your_fingerprint">Your fingerprint</string>
+    <string name="remote_fingerprint">Remote Fingerprint</string>
+    <string name="shared_secret_hint">Hint or Question</string>
+    <string name="shared_secret_secret">Shared Secret</string>
 </resources>

src/main/res/values/styles.xml

@@ -51,6 +51,14 @@
         <item name="android:textSize">?TextSizeCaption</item>
     </style>
 
+    <style name="ToolbarTitleAppearance" parent="@style/TextAppearance.Widget.AppCompat.Toolbar.Title">
+        <item name="android:textSize">18dp</item>
+    </style>
+
+    <style name="ToolbarSubtitleAppearance" parent="@style/TextAppearance.Widget.AppCompat.Toolbar.Subtitle">
+        <item name="android:textSize">13dp</item>
+    </style>
+
     <style name="Widget.Conversations.EditText" parent="Widget.AppCompat.EditText">
         <item name="android:textSize">?TextSizeInput</item>
     </style>

src/main/res/values/themes.xml

@@ -59,6 +59,7 @@
         <item name="ic_attach_videocam" type="reference">@drawable/ic_attach_videocam</item>
         <item name="ic_attach_document" type="reference">@drawable/ic_attach_document</item>
         <item name="ic_pin" type="reference">@drawable/ic_pin_black</item>
+        <item name="ic_subject" type="reference">@drawable/ic_subject_black</item>
         <item name="ic_close" type="reference">@drawable/ic_close_24dp_black</item>
         <item name="ic_attach_location" type="reference">@drawable/ic_attach_location</item>
         <item name="ic_attach_photo" type="reference">@drawable/ic_attach_photo</item>
@@ -152,6 +153,7 @@
         <item name="ic_group_unselected" type="reference">@drawable/outline_group_black_24dp</item>
         <item name="ic_group_selected" type="reference">@drawable/ic_group_selected_black_24</item>
         <item name="ic_group_16" type="reference">@drawable/ic_group_selected_black_16</item>
+        <item name="ic_secret_chat_16" type="reference">@drawable/ic_secret_chat_16dp_black</item>
 
         <item name="icon_notifications" type="reference">@drawable/ic_notifications_black_24dp
         </item>
@@ -239,6 +241,7 @@
         <item name="ic_attach_videocam" type="reference">@drawable/ic_attach_videocam_white</item>
         <item name="ic_attach_document" type="reference">@drawable/ic_attach_document_white</item>
         <item name="ic_pin" type="reference">@drawable/ic_pin_white</item>
+        <item name="ic_subject" type="reference">@drawable/ic_subject_white</item>
         <item name="ic_close" type="reference">@drawable/ic_close_24dp</item>
         <item name="ic_attach_location" type="reference">@drawable/ic_attach_location_white</item>
         <item name="ic_attach_photo" type="reference">@drawable/ic_attach_photo_white</item>
@@ -329,6 +332,7 @@
         <item name="ic_group_unselected" type="reference">@drawable/outline_group_white_24</item>
         <item name="ic_group_selected" type="reference">@drawable/ic_group_selected_white_24</item>
         <item name="ic_group_16" type="reference">@drawable/ic_group_selected_white_16</item>
+        <item name="ic_secret_chat_16" type="reference">@drawable/ic_secret_chat_16dp_white</item>
 
         <item name="icon_notifications" type="reference">@drawable/ic_notifications_white_24dp
         </item>

src/main/res/xml/preferences.xml

@@ -64,6 +64,16 @@
                 android:key="always_full_timestamps"
                 android:summary="@string/pref_always_show_full_timestamps_summary"
                 android:title="@string/pref_always_show_full_timestamps" />
+            <CheckBoxPreference
+                android:defaultValue="@bool/use_green_background"
+                android:key="show_contact_status"
+                android:summary="@string/pref_show_contact_presence_details"
+                android:title="@string/pref_show_contact_presence" />
+            <CheckBoxPreference
+                android:defaultValue="@bool/use_green_background"
+                android:key="show_account_indicator"
+                android:summary="@string/pref_show_account_indicator_details"
+                android:title="@string/pref_show_account_indicator" />
         </PreferenceCategory>
 
         <PreferenceCategory android:title="@string/pref_navigation">