Basic encryption support

app/build.gradle

@@ -84,6 +84,7 @@ dependencies {
     def jsoup_version = "1.11.3"
     def jcharset_version = "2.0"
     def dnsjava_version = "2.1.8"
+    def openpgp_version = "12.0"
 
     implementation "androidx.appcompat:appcompat:$androidx_version"
     implementation "androidx.recyclerview:recyclerview:$androidx_version"
@@ -113,6 +114,9 @@ dependencies {
     // http://www.xbill.org/dnsjava/
     implementation "dnsjava:dnsjava:$dnsjava_version"
 
+    // https://github.com/open-keychain/openpgp-api
+    implementation "org.sufficientlysecure:openpgp-api:$openpgp_version"
+
     // git clone https://android.googlesource.com/platform/frameworks/opt/colorpicker
     implementation project(path: ':colorpicker')
 }

app/src/main/java/eu/faircode/email/ActivityCompose.java

@@ -35,6 +35,7 @@ public class ActivityCompose extends ActivityBilling implements FragmentManager.
     static final int REQUEST_CONTACT_BCC = 3;
     static final int REQUEST_IMAGE = 4;
     static final int REQUEST_ATTACHMENT = 5;
+    static final int REQUEST_ENCRYPT = 6;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {

app/src/main/java/eu/faircode/email/ActivityView.java

@@ -20,6 +20,7 @@ package eu.faircode.email;
 */
 
 import android.app.Activity;
+import android.app.PendingIntent;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.DialogInterface;
@@ -45,14 +46,22 @@ import android.widget.ListView;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import com.google.android.material.snackbar.Snackbar;
+
 import org.json.JSONArray;
 import org.json.JSONObject;
+import org.openintents.openpgp.OpenPgpError;
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.openintents.openpgp.util.OpenPgpServiceConnection;
 
 import java.io.BufferedReader;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.FileReader;
+import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.URL;
 import java.text.Collator;
@@ -76,7 +85,6 @@ import androidx.lifecycle.Lifecycle;
 import androidx.lifecycle.Observer;
 import androidx.lifecycle.ViewModelProviders;
 import androidx.localbroadcastmanager.content.LocalBroadcastManager;
-import androidx.paging.PagedList;
 
 public class ActivityView extends ActivityBilling implements FragmentManager.OnBackStackChangedListener {
     private View view;
@@ -85,7 +93,9 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
     private ActionBarDrawerToggle drawerToggle;
 
     private long attachment = -1;
-    private PagedList<TupleMessageEx> messages = null;
+    private long decryptId = -1;
+    private File decryptFile = null;
+    private OpenPgpServiceConnection pgpService;
 
     private static final int ATTACHMENT_BUFFER_SIZE = 8192; // bytes
 
@@ -95,6 +105,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
 
     static final int REQUEST_ATTACHMENT = 1;
     static final int REQUEST_INVITE = 2;
+    static final int REQUEST_DECRYPT = 3;
 
     static final String ACTION_VIEW_MESSAGES = BuildConfig.APPLICATION_ID + ".VIEW_MESSAGES";
     static final String ACTION_VIEW_THREAD = BuildConfig.APPLICATION_ID + ".VIEW_THREAD";
@@ -102,6 +113,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
     static final String ACTION_EDIT_FOLDER = BuildConfig.APPLICATION_ID + ".EDIT_FOLDER";
     static final String ACTION_EDIT_ANSWER = BuildConfig.APPLICATION_ID + ".EDIT_ANSWER";
     static final String ACTION_STORE_ATTACHMENT = BuildConfig.APPLICATION_ID + ".STORE_ATTACHMENT";
+    static final String ACTION_DECRYPT = BuildConfig.APPLICATION_ID + ".DECRYPT";
     static final String ACTION_SHOW_PRO = BuildConfig.APPLICATION_ID + ".SHOW_PRO";
 
     static final String UPDATE_LATEST_API = "https://api.github.com/repos/M66B/open-source-email/releases/latest";
@@ -262,6 +274,9 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         checkCrash();
         if (!Helper.isPlayStoreInstall(this))
             checkUpdate();
+
+        pgpService = new OpenPgpServiceConnection(this, "org.sufficientlysecure.keychain");
+        pgpService.bindToService();
     }
 
     @Override
@@ -294,6 +309,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         iff.addAction(ACTION_EDIT_FOLDER);
         iff.addAction(ACTION_EDIT_ANSWER);
         iff.addAction(ACTION_STORE_ATTACHMENT);
+        iff.addAction(ACTION_DECRYPT);
         iff.addAction(ACTION_SHOW_PRO);
         lbm.registerReceiver(receiver, iff);
 
@@ -369,6 +385,14 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         lbm.unregisterReceiver(receiver);
     }
 
+    @Override
+    protected void onDestroy() {
+        if (pgpService != null)
+            pgpService.unbindFromService();
+
+        super.onDestroy();
+    }
+
     @Override
     public void onConfigurationChanged(Configuration newConfig) {
         super.onConfigurationChanged(newConfig);
@@ -801,6 +825,8 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                 onEditAnswer(intent);
             else if (ACTION_STORE_ATTACHMENT.equals(intent.getAction()))
                 onStoreAttachment(intent);
+            else if (ACTION_DECRYPT.equals(intent.getAction()))
+                onDecrypt(intent);
             else if (ACTION_SHOW_PRO.equals(intent.getAction()))
                 onShowPro(intent);
         }
@@ -868,76 +894,207 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
         startActivityForResult(create, REQUEST_ATTACHMENT);
     }
 
+    private void onDecrypt(Intent intent) {
+        Bundle args = new Bundle();
+        args.putLong("id", intent.getLongExtra("id", -1));
+
+        new SimpleTask<File>() {
+            @Override
+            protected File onLoad(Context context, Bundle args) throws Throwable {
+                long id = args.getLong("id");
+
+                DB db = DB.getInstance(context);
+                try {
+                    db.beginTransaction();
+
+                    for (EntityAttachment attachment : db.attachment().getAttachments(id))
+                        if (attachment.available && "encrypted.asc".equals(attachment.name))
+                            return EntityAttachment.getFile(context, attachment.id);
+
+                    db.setTransactionSuccessful();
+                } finally {
+                    db.endTransaction();
+                }
+
+                return null;
+            }
+
+            @Override
+            protected void onLoaded(Bundle args, File file) {
+                if (file != null)
+                    try {
+                        if (!pgpService.isBound())
+                            throw new IllegalArgumentException(getString(R.string.title_no_openpgp));
+
+                        Intent data = new Intent();
+                        data.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
+                        data.putExtra(OpenPgpApi.EXTRA_USER_IDS, new String[]{args.getString("to")});
+                        data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+                        decrypt(data, args.getLong("id"), file);
+                    } catch (Throwable ex) {
+                        if (ex instanceof IllegalArgumentException)
+                            Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                        else
+                            Helper.unexpectedError(ActivityView.this, ex);
+                    }
+            }
+        }.load(this, args);
+    }
+
     private void onShowPro(Intent intent) {
         FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
         fragmentTransaction.replace(R.id.content_frame, new FragmentPro()).addToBackStack("pro");
         fragmentTransaction.commit();
     }
 
+    private void decrypt(Intent data, final long id, final File file) throws FileNotFoundException {
+        final OpenPgpApi api = new OpenPgpApi(this, pgpService.getService());
+        final FileInputStream msg = new FileInputStream(file);
+        final ByteArrayOutputStream decrypted = new ByteArrayOutputStream();
+
+        api.executeApiAsync(data, msg, decrypted, new OpenPgpApi.IOpenPgpCallback() {
+            @Override
+            public void onReturn(Intent result) {
+                Log.i(Helper.TAG, "Pgp result=" + result);
+                Bundle extras = result.getExtras();
+                for (String key : extras.keySet())
+                    Log.i(Helper.TAG, key + "=" + extras.get(key));
+
+                try {
+                    switch (result.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR)) {
+                        case OpenPgpApi.RESULT_CODE_SUCCESS:
+                            Bundle args = new Bundle();
+                            args.putLong("id", id);
+
+                            new SimpleTask<Void>() {
+                                @Override
+                                protected Void onLoad(Context context, Bundle args) throws Throwable {
+                                    long id = args.getLong("id");
+
+                                    DB db = DB.getInstance(context);
+                                    EntityMessage message = db.message().getMessage(id);
+                                    message.write(context, decrypted.toString("UTF-8"));
+                                    db.message().setMessageStored(id, new Date().getTime());
+
+                                    return null;
+                                }
+
+                                @Override
+                                protected void onException(Bundle args, Throwable ex) {
+                                    Helper.unexpectedError(ActivityView.this, ex);
+                                }
+                            }.load(ActivityView.this, args);
+
+                            break;
+
+                        case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+                            decryptId = id;
+                            decryptFile = file;
+                            PendingIntent pi = result.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+                            startIntentSenderForResult(
+                                    pi.getIntentSender(),
+                                    ActivityView.REQUEST_DECRYPT,
+                                    null, 0, 0, 0, null);
+                            break;
+
+                        case OpenPgpApi.RESULT_CODE_ERROR:
+                            OpenPgpError error = result.getParcelableExtra(OpenPgpApi.RESULT_ERROR);
+                            throw new IllegalArgumentException(error.getMessage());
+                    }
+                } catch (Throwable ex) {
+                    if (ex instanceof IllegalArgumentException)
+                        Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                    else
+                        Helper.unexpectedError(ActivityView.this, ex);
+                } finally {
+                    try {
+                        msg.close();
+                    } catch (IOException ex) {
+                        Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                    }
+                }
+            }
+        });
+    }
+
     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         Log.i(Helper.TAG, "View onActivityResult request=" + requestCode + " result=" + resultCode + " data=" + data);
         if (resultCode == Activity.RESULT_OK)
             if (requestCode == REQUEST_ATTACHMENT) {
-                Bundle args = new Bundle();
-                args.putLong("id", attachment);
-                args.putParcelable("uri", data.getData());
-                new SimpleTask<Void>() {
-                    @Override
-                    protected Void onLoad(Context context, Bundle args) throws Throwable {
-                        long id = args.getLong("id");
-                        Uri uri = args.getParcelable("uri");
-
-                        File file = EntityAttachment.getFile(context, id);
-
-                        ParcelFileDescriptor pfd = null;
-                        FileOutputStream fos = null;
-                        FileInputStream fis = null;
-                        try {
-                            pfd = context.getContentResolver().openFileDescriptor(uri, "w");
-                            fos = new FileOutputStream(pfd.getFileDescriptor());
-                            fis = new FileInputStream(file);
-
-                            byte[] buffer = new byte[ATTACHMENT_BUFFER_SIZE];
-                            int read;
-                            while ((read = fis.read(buffer)) != -1) {
-                                fos.write(buffer, 0, read);
-                            }
-                        } finally {
-                            try {
-                                if (pfd != null)
-                                    pfd.close();
-                            } catch (Throwable ex) {
-                                Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
-                            }
-                            try {
-                                if (fos != null)
-                                    fos.close();
-                            } catch (Throwable ex) {
-                                Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
-                            }
+                if (data != null) {
+                    Bundle args = new Bundle();
+                    args.putLong("id", attachment);
+                    args.putParcelable("uri", data.getData());
+
+                    new SimpleTask<Void>() {
+                        @Override
+                        protected Void onLoad(Context context, Bundle args) throws Throwable {
+                            long id = args.getLong("id");
+                            Uri uri = args.getParcelable("uri");
+
+                            File file = EntityAttachment.getFile(context, id);
+
+                            ParcelFileDescriptor pfd = null;
+                            FileOutputStream fos = null;
+                            FileInputStream fis = null;
                             try {
-                                if (fis != null)
-                                    fis.close();
-                            } catch (Throwable ex) {
-                                Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                                pfd = context.getContentResolver().openFileDescriptor(uri, "w");
+                                fos = new FileOutputStream(pfd.getFileDescriptor());
+                                fis = new FileInputStream(file);
+
+                                byte[] buffer = new byte[ATTACHMENT_BUFFER_SIZE];
+                                int read;
+                                while ((read = fis.read(buffer)) != -1) {
+                                    fos.write(buffer, 0, read);
+                                }
+                            } finally {
+                                try {
+                                    if (pfd != null)
+                                        pfd.close();
+                                } catch (Throwable ex) {
+                                    Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                                }
+                                try {
+                                    if (fos != null)
+                                        fos.close();
+                                } catch (Throwable ex) {
+                                    Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                                }
+                                try {
+                                    if (fis != null)
+                                        fis.close();
+                                } catch (Throwable ex) {
+                                    Log.w(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                                }
                             }
-                        }
 
-                        return null;
-                    }
+                            return null;
+                        }
 
-                    @Override
-                    protected void onLoaded(Bundle args, Void data) {
-                        Toast.makeText(ActivityView.this, R.string.title_attachment_saved, Toast.LENGTH_LONG).show();
-                    }
+                        @Override
+                        protected void onLoaded(Bundle args, Void data) {
+                            Toast.makeText(ActivityView.this, R.string.title_attachment_saved, Toast.LENGTH_LONG).show();
+                        }
 
-                    @Override
-                    protected void onException(Bundle args, Throwable ex) {
-                        Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
-                        Helper.unexpectedError(ActivityView.this, ex);
+                        @Override
+                        protected void onException(Bundle args, Throwable ex) {
+                            Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                            Helper.unexpectedError(ActivityView.this, ex);
+                        }
+                    }.load(this, args);
+                }
+            } else if (requestCode == REQUEST_DECRYPT) {
+                if (data != null)
+                    try {
+                        decrypt(data, decryptId, decryptFile);
+                    } catch (Throwable ex) {
+                        if (ex instanceof IllegalArgumentException)
+                            Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                        else
+                            Helper.unexpectedError(ActivityView.this, ex);
                     }
-                }.load(this, args);
             }
     }
 }

app/src/main/java/eu/faircode/email/AdapterMessage.java

@@ -1071,6 +1071,14 @@ public class AdapterMessage extends PagedListAdapter<TupleMessageEx, AdapterMess
                             .putExtra("from", MessageHelper.getFormattedAddresses(data.message.from, true)));
         }
 
+        private void onDecrypt(ActionData data) {
+            LocalBroadcastManager lbm = LocalBroadcastManager.getInstance(context);
+            lbm.sendBroadcast(
+                    new Intent(ActivityView.ACTION_DECRYPT)
+                            .putExtra("id", data.message.id)
+                            .putExtra("to", ((InternetAddress) data.message.to[0]).getAddress()));
+        }
+
         private void onMore(final ActionData data) {
             boolean inOutbox = EntityFolder.OUTBOX.equals(data.message.folderType);
             boolean show_headers = properties.showHeaders(data.message.id);
@@ -1086,18 +1094,20 @@ public class AdapterMessage extends PagedListAdapter<TupleMessageEx, AdapterMess
             popupMenu.getMenu().findItem(R.id.menu_reply_all).setEnabled(data.message.content);
             popupMenu.getMenu().findItem(R.id.menu_reply_all).setVisible(!inOutbox);
 
-            popupMenu.getMenu().findItem(R.id.menu_show_headers).setChecked(show_headers);
-            popupMenu.getMenu().findItem(R.id.menu_show_headers).setVisible(data.message.uid != null);
+            popupMenu.getMenu().findItem(R.id.menu_answer).setEnabled(data.message.content);
+            popupMenu.getMenu().findItem(R.id.menu_answer).setVisible(!inOutbox);
 
-            popupMenu.getMenu().findItem(R.id.menu_show_html).setEnabled(data.message.content && Helper.classExists("android.webkit.WebView"));
+            popupMenu.getMenu().findItem(R.id.menu_unseen).setVisible(data.message.uid != null && !inOutbox);
 
             popupMenu.getMenu().findItem(R.id.menu_flag).setChecked(data.message.unflagged != 1);
             popupMenu.getMenu().findItem(R.id.menu_flag).setVisible(data.message.uid != null && !inOutbox);
 
-            popupMenu.getMenu().findItem(R.id.menu_unseen).setVisible(data.message.uid != null && !inOutbox);
+            popupMenu.getMenu().findItem(R.id.menu_show_headers).setChecked(show_headers);
+            popupMenu.getMenu().findItem(R.id.menu_show_headers).setVisible(data.message.uid != null);
 
-            popupMenu.getMenu().findItem(R.id.menu_answer).setEnabled(data.message.content);
-            popupMenu.getMenu().findItem(R.id.menu_answer).setVisible(!inOutbox);
+            popupMenu.getMenu().findItem(R.id.menu_show_html).setEnabled(data.message.content && Helper.classExists("android.webkit.WebView"));
+
+            popupMenu.getMenu().findItem(R.id.menu_decrypt).setEnabled(data.message.to != null && data.message.to.length > 0);
 
             popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
                 @Override
@@ -1112,20 +1122,23 @@ public class AdapterMessage extends PagedListAdapter<TupleMessageEx, AdapterMess
                         case R.id.menu_reply_all:
                             onReplyAll(data);
                             return true;
-                        case R.id.menu_show_headers:
-                            onShowHeaders(data);
+                        case R.id.menu_answer:
+                            onAnswer(data);
                             return true;
-                        case R.id.menu_show_html:
-                            onShowHtml(data);
+                        case R.id.menu_unseen:
+                            onUnseen(data);
                             return true;
                         case R.id.menu_flag:
                             onFlag(data);
                             return true;
-                        case R.id.menu_unseen:
-                            onUnseen(data);
+                        case R.id.menu_show_headers:
+                            onShowHeaders(data);
                             return true;
-                        case R.id.menu_answer:
-                            onAnswer(data);
+                        case R.id.menu_show_html:
+                            onShowHtml(data);
+                            return true;
+                        case R.id.menu_decrypt:
+                            onDecrypt(data);
                             return true;
                         default:
                             return false;
@@ -1382,7 +1395,6 @@ public class AdapterMessage extends PagedListAdapter<TupleMessageEx, AdapterMess
 
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
 
-
         this.contacts = (ContextCompat.checkSelfPermission(context, Manifest.permission.READ_CONTACTS)
                 == PackageManager.PERMISSION_GRANTED);
         this.avatars = (prefs.getBoolean("avatars", true) && this.contacts);

app/src/main/java/eu/faircode/email/DaoMessage.java

@@ -225,6 +225,9 @@ public interface DaoMessage {
     @Query("UPDATE message SET headers = :headers WHERE id = :id")
     int setMessageHeaders(long id, String headers);
 
+    @Query("UPDATE message SET stored = :stored WHERE id = :id")
+    int setMessageStored(long id, long stored);
+
     @Query("UPDATE message SET ui_ignored = 1" +
             " WHERE NOT ui_ignored" +
             " AND folder IN (SELECT id FROM folder WHERE type = '" + EntityFolder.INBOX + "')")

app/src/main/java/eu/faircode/email/EntityMessage.java

@@ -37,7 +37,6 @@ import javax.mail.Address;
 import androidx.annotation.NonNull;
 import androidx.room.Entity;
 import androidx.room.ForeignKey;
-import androidx.room.Ignore;
 import androidx.room.Index;
 import androidx.room.PrimaryKey;
 
@@ -116,9 +115,6 @@ public class EntityMessage implements Serializable {
     public Boolean ui_ignored;
     public String error;
 
-    @Ignore
-    String body = null;
-
     static String generateMessageId() {
         StringBuffer sb = new StringBuffer();
         sb.append('<')
@@ -139,9 +135,8 @@ public class EntityMessage implements Serializable {
         File file = getFile(context, id);
         BufferedWriter out = null;
         try {
-            this.body = (body == null ? "" : body);
             out = new BufferedWriter(new FileWriter(file));
-            out.write(this.body);
+            out.write(body == null ? "" : body);
         } finally {
             if (out != null)
                 try {
@@ -153,9 +148,7 @@ public class EntityMessage implements Serializable {
     }
 
     String read(Context context) throws IOException {
-        if (body == null)
-            body = read(context, this.id);
-        return body;
+        return read(context, this.id);
     }
 
     static String read(Context context, Long id) throws IOException {

app/src/main/java/eu/faircode/email/FragmentCompose.java

@@ -20,6 +20,7 @@ package eu.faircode.email;
 */
 
 import android.Manifest;
+import android.app.PendingIntent;
 import android.content.ClipboardManager;
 import android.content.Context;
 import android.content.DialogInterface;
@@ -64,8 +65,14 @@ import android.widget.Toast;
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 import com.google.android.material.snackbar.Snackbar;
 
+import org.openintents.openpgp.OpenPgpError;
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.openintents.openpgp.util.OpenPgpServiceConnection;
+
 import java.io.BufferedOutputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -119,6 +126,8 @@ public class FragmentCompose extends FragmentEx {
     private long working = -1;
     private boolean autosave = false;
 
+    private OpenPgpServiceConnection pgpService;
+
     @Override
     @Nullable
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
@@ -189,20 +198,14 @@ public class FragmentCompose extends FragmentEx {
             @Override
             public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                 int action = item.getItemId();
-                if (action == R.id.action_delete) {
-                    new DialogBuilderLifecycle(getContext(), getViewLifecycleOwner())
-                            .setMessage(R.string.title_ask_discard)
-                            .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
-                                @Override
-                                public void onClick(DialogInterface dialog, int which) {
-                                    onAction(R.id.action_delete);
-                                }
-                            })
-                            .setNegativeButton(android.R.string.cancel, null)
-                            .show();
+                switch (action) {
+                    case R.id.action_delete:
+                        onDelete();
+                        break;
 
-                } else
-                    onAction(action);
+                    default:
+                        onAction(action);
+                }
                 return false;
             }
         });
@@ -298,12 +301,19 @@ public class FragmentCompose extends FragmentEx {
         adapter = new AdapterAttachment(getContext(), getViewLifecycleOwner(), false);
         rvAttachment.setAdapter(adapter);
 
+        pgpService = new OpenPgpServiceConnection(getContext(), "org.sufficientlysecure.keychain");
+        pgpService.bindToService();
+
         return view;
     }
 
     @Override
     public void onDestroyView() {
         adapter = null;
+
+        if (pgpService != null)
+            pgpService.unbindFromService();
+
         super.onDestroyView();
     }
 
@@ -457,6 +467,145 @@ public class FragmentCompose extends FragmentEx {
         grpAddresses.setVisibility(grpAddresses.getVisibility() == View.GONE ? View.VISIBLE : View.GONE);
     }
 
+    private void onDelete() {
+        new DialogBuilderLifecycle(getContext(), getViewLifecycleOwner())
+                .setMessage(R.string.title_ask_discard)
+                .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        onAction(R.id.action_delete);
+                    }
+                })
+                .setNegativeButton(android.R.string.cancel, null)
+                .show();
+    }
+
+    private void onEncrypt() {
+        try {
+            if (!pgpService.isBound())
+                throw new IllegalArgumentException(getString(R.string.title_no_openpgp));
+
+            String to = etTo.getText().toString();
+            InternetAddress ato[] = (TextUtils.isEmpty(to) ? new InternetAddress[0] : InternetAddress.parse(to));
+            if (ato.length == 0)
+                throw new IllegalArgumentException(getString(R.string.title_to_missing));
+
+            String[] tos = new String[ato.length];
+            for (int i = 0; i < ato.length; i++)
+                tos[i] = ato[i].getAddress();
+
+            Intent data = new Intent();
+            data.setAction(OpenPgpApi.ACTION_ENCRYPT);
+            data.putExtra(OpenPgpApi.EXTRA_USER_IDS, tos);
+            data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+            encrypt(data);
+        } catch (Throwable ex) {
+            if (ex instanceof IllegalArgumentException)
+                Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+            else
+                Helper.unexpectedError(getContext(), ex);
+        }
+    }
+
+    private void encrypt(Intent data) throws IOException {
+        final OpenPgpApi api = new OpenPgpApi(getContext(), pgpService.getService());
+        final FileInputStream msg = new FileInputStream(EntityMessage.getFile(getContext(), working));
+        final ByteArrayOutputStream encrypted = new ByteArrayOutputStream();
+
+        final Bundle args = new Bundle();
+        args.putLong("id", working);
+
+        api.executeApiAsync(data, msg, encrypted, new OpenPgpApi.IOpenPgpCallback() {
+            @Override
+            public void onReturn(Intent result) {
+                Log.i(Helper.TAG, "Pgp result=" + result);
+                Bundle extras = result.getExtras();
+                for (String key : extras.keySet())
+                    Log.i(Helper.TAG, key + "=" + extras.get(key));
+
+                try {
+                    switch (result.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR)) {
+                        case OpenPgpApi.RESULT_CODE_SUCCESS:
+                            new SimpleTask<Void>() {
+                                @Override
+                                protected Void onLoad(Context context, Bundle args) throws Throwable {
+                                    long id = args.getLong("id");
+                                    EntityAttachment attachment = new EntityAttachment();
+
+                                    DB db = DB.getInstance(context);
+                                    try {
+                                        db.beginTransaction();
+
+                                        int seq = db.attachment().getAttachmentCount(id);
+
+                                        attachment.message = id;
+                                        attachment.sequence = seq + 1;
+                                        attachment.name = "encrypted.asc";
+                                        attachment.type = "application/octet-stream";
+                                        attachment.id = db.attachment().insertAttachment(attachment);
+
+                                        File file = EntityAttachment.getFile(context, attachment.id);
+
+                                        OutputStream os = null;
+                                        try {
+                                            os = new BufferedOutputStream(new FileOutputStream(file));
+                                            byte[] data = encrypted.toByteArray();
+                                            os.write(data);
+
+                                            attachment.size = data.length;
+                                            attachment.progress = null;
+                                            attachment.available = true;
+                                            db.attachment().updateAttachment(attachment);
+                                        } finally {
+                                            if (os != null)
+                                                os.close();
+                                        }
+
+                                        db.setTransactionSuccessful();
+                                    } finally {
+                                        db.endTransaction();
+                                    }
+
+                                    return null;
+                                }
+
+                                @Override
+                                protected void onException(Bundle args, Throwable ex) {
+                                    Helper.unexpectedError(getContext(), ex);
+                                }
+                            }.load(FragmentCompose.this, args);
+
+                            break;
+
+                        case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED:
+                            PendingIntent pi = result.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+                            startIntentSenderForResult(
+                                    pi.getIntentSender(),
+                                    ActivityCompose.REQUEST_ENCRYPT,
+                                    null, 0, 0, 0, null);
+                            break;
+
+                        case OpenPgpApi.RESULT_CODE_ERROR:
+                            OpenPgpError error = result.getParcelableExtra(OpenPgpApi.RESULT_ERROR);
+                            throw new IllegalArgumentException(error.getMessage());
+                    }
+                } catch (Throwable ex) {
+                    if (ex instanceof IllegalArgumentException)
+                        Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                    else
+                        Helper.unexpectedError(getContext(), ex);
+                } finally {
+                    try {
+                        msg.close();
+                    } catch (IOException ex) {
+                        Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                    }
+                }
+            }
+        });
+    }
+
     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
         Log.i(Helper.TAG, "Compose onActivityResult request=" + requestCode + " result=" + resultCode + " data=" + data);
@@ -467,6 +616,16 @@ public class FragmentCompose extends FragmentEx {
             } else if (requestCode == ActivityCompose.REQUEST_ATTACHMENT) {
                 if (data != null)
                     handleAddAttachment(data, false);
+            } else if (requestCode == ActivityCompose.REQUEST_ENCRYPT) {
+                if (data != null)
+                    try {
+                        encrypt(data);
+                    } catch (Throwable ex) {
+                        if (ex instanceof IllegalArgumentException)
+                            Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                        else
+                            Helper.unexpectedError(getContext(), ex);
+                    }
             } else {
                 if (data != null)
                     handlePickContact(requestCode, data);
@@ -626,7 +785,8 @@ public class FragmentCompose extends FragmentEx {
         actionLoader.load(this, args);
     }
 
-    private static EntityAttachment addAttachment(Context context, long id, Uri uri, boolean image) throws IOException {
+    private static EntityAttachment addAttachment(Context context, long id, Uri uri,
+                                                  boolean image) throws IOException {
         EntityAttachment attachment = new EntityAttachment();
 
         String name = null;
@@ -1159,7 +1319,7 @@ public class FragmentCompose extends FragmentEx {
                             Toast.makeText(context, R.string.title_draft_deleted, Toast.LENGTH_LONG).show();
                         }
                     });
-                } else if (action == R.id.action_save) {
+                } else if (action == R.id.action_save || action == R.id.action_encrypt) {
                     db.message().updateMessage(draft);
                     draft.write(context, body);
 
@@ -1250,6 +1410,9 @@ public class FragmentCompose extends FragmentEx {
             } else if (action == R.id.action_save) {
                 // Do nothing
 
+            } else if (action == R.id.action_encrypt) {
+                onEncrypt();
+
             } else if (action == R.id.action_send) {
                 autosave = false;
                 getFragmentManager().popBackStack();

app/src/main/java/eu/faircode/email/MessageHelper.java

@@ -195,7 +195,41 @@ public class MessageHelper {
         if (message.subject != null)
             imessage.setSubject(message.subject);
 
-        // TODO: plain message?
+        imessage.setSentDate(new Date());
+
+        for (final EntityAttachment attachment : attachments)
+            if (attachment.available && "encrypted.asc".equals(attachment.name)) {
+                Multipart multipart = new MimeMultipart("encrypted; protocol=\"application/pgp-encrypted\"");
+
+                BodyPart pgp = new MimeBodyPart();
+                pgp.setContent("", "application/pgp-encrypted");
+                multipart.addBodyPart(pgp);
+
+                BodyPart bpAttachment = new MimeBodyPart();
+                bpAttachment.setFileName(attachment.name);
+
+                File file = EntityAttachment.getFile(context, attachment.id);
+                FileDataSource dataSource = new FileDataSource(file);
+                dataSource.setFileTypeMap(new FileTypeMap() {
+                    @Override
+                    public String getContentType(File file) {
+                        return attachment.type;
+                    }
+
+                    @Override
+                    public String getContentType(String filename) {
+                        return attachment.type;
+                    }
+                });
+                bpAttachment.setDataHandler(new DataHandler(dataSource));
+                bpAttachment.setDisposition(Part.INLINE);
+
+                multipart.addBodyPart(bpAttachment);
+
+                imessage.setContent(multipart);
+
+                return imessage;
+            }
 
         String body = message.read(context);
 
@@ -246,8 +280,6 @@ public class MessageHelper {
             imessage.setContent(multipart);
         }
 
-        imessage.setSentDate(new Date());
-
         return imessage;
     }
 

app/src/main/res/drawable/baseline_lock_24.xml

@@ -0,0 +1,10 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0"
+        android:tint="?attr/colorControlNormal">
+    <path
+        android:fillColor="@android:color/white"
+        android:pathData="M18,8h-1L17,6c0,-2.76 -2.24,-5 -5,-5S7,3.24 7,6v2L6,8c-1.1,0 -2,0.9 -2,2v10c0,1.1 0.9,2 2,2h12c1.1,0 2,-0.9 2,-2L20,10c0,-1.1 -0.9,-2 -2,-2zM12,17c-1.1,0 -2,-0.9 -2,-2s0.9,-2 2,-2 2,0.9 2,2 -0.9,2 -2,2zM15.1,8L8.9,8L8.9,6c0,-1.71 1.39,-3.1 3.1,-3.1 1.71,0 3.1,1.39 3.1,3.1v2z"/>
+</vector>

app/src/main/res/menu/action_compose.xml

@@ -11,6 +11,11 @@
         android:icon="@drawable/baseline_save_alt_24"
         android:title="@string/title_save" />
 
+    <item
+        android:id="@+id/action_encrypt"
+        android:icon="@drawable/baseline_lock_24"
+        android:title="@string/title_encrypt" />
+
     <item
         android:id="@+id/action_send"
         android:icon="@drawable/baseline_send_24"

app/src/main/res/menu/menu_message.xml

@@ -33,4 +33,8 @@
     <item
         android:id="@+id/menu_show_html"
         android:title="@string/title_show_html" />
+
+    <item
+        android:id="@+id/menu_decrypt"
+        android:title="@string/title_decrypt" />
 </menu>

app/src/main/res/values/strings.xml

@@ -182,6 +182,7 @@
     <string name="title_reply_all">Reply to all</string>
     <string name="title_show_headers">Show headers</string>
     <string name="title_show_html">Show original</string>
+    <string name="title_decrypt">Decrypt</string>
 
     <string name="title_trash">Trash</string>
     <string name="title_delete">Delete</string>
@@ -211,6 +212,7 @@
     <string name="title_body_hint">Your message</string>
     <string name="title_discard">Discard</string>
     <string name="title_save">Save</string>
+    <string name="title_encrypt">Encrypt</string>
     <string name="title_send">Send</string>
 
     <string name="title_clipboard_empty">Clipboard empty</string>
@@ -228,6 +230,8 @@
     <string name="title_draft_saved">Draft saved</string>
     <string name="title_queued">Sending message</string>
 
+    <string name="title_no_openpgp">OpenPgp not found</string>
+
     <string name="title_search">Search</string>
     <string name="title_search_hint">Search on server</string>
     <string name="title_searching">Searching \'%1$s\'</string>