Basic OpenPGP support

Fixes #43

app/build.gradle

@@ -67,6 +67,8 @@ dependencies {
     // https://developer.android.com/topic/libraries/architecture/adding-components.html
     // https://developer.android.com/jetpack/docs/release-notes
 
+    // https://github.com/open-keychain/openpgp-api
+
     def androidx_version = "1.0.0-rc01"
     def constraintlayout_version = "1.1.2"
     def lifecycle_version = "2.0.0-rc01"
@@ -76,6 +78,7 @@ dependencies {
     def javamail_version = "1.6.0"
     def jsoup_version = "1.11.3"
     def jcharset_version = "2.0"
+    def openpgp_version = "12.0"
 
     implementation "androidx.appcompat:appcompat:$androidx_version"
     implementation "androidx.recyclerview:recyclerview:$androidx_version"
@@ -99,4 +102,6 @@ dependencies {
     implementation "org.jsoup:jsoup:$jsoup_version"
 
     implementation "net.freeutils:jcharset:$jcharset_version"
+
+    implementation "org.sufficientlysecure:openpgp-api:$openpgp_version"
 }

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

@@ -36,6 +36,7 @@ public class ActivityCompose extends ActivityBase implements FragmentManager.OnB
     static final int REQUEST_CONTACT_CC = 2;
     static final int REQUEST_CONTACT_BCC = 3;
     static final int REQUEST_ATTACHMENT = 4;
+    static final int REQUEST_OPENPGP = 5;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {

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

@@ -91,6 +91,8 @@ public class ActivityView extends ActivityBase implements FragmentManager.OnBack
 
     static final int REQUEST_VIEW = 1;
     static final int REQUEST_UNSEEN = 2;
+    static final int REQUEST_OPENPGP = 3;
+    static final int REQUEST_ATTACHMENT_OFFSET = 10;
 
     static final String ACTION_VIEW_MESSAGES = BuildConfig.APPLICATION_ID + ".VIEW_MESSAGES";
     static final String ACTION_VIEW_MESSAGE = BuildConfig.APPLICATION_ID + ".VIEW_MESSAGE";
@@ -692,7 +694,7 @@ public class ActivityView extends ActivityBase implements FragmentManager.OnBack
                 create.addCategory(Intent.CATEGORY_OPENABLE);
                 create.setType(intent.getStringExtra("type"));
                 create.putExtra(Intent.EXTRA_TITLE, intent.getStringExtra("name"));
-                startActivityForResult(create, (int) intent.getLongExtra("id", -1));
+                startActivityForResult(create, (int) intent.getLongExtra("id", -1) + REQUEST_ATTACHMENT_OFFSET);
 
             } else if (ACTION_ACTIVATE_PRO.equals(intent.getAction())) {
                 try {
@@ -724,9 +726,9 @@ public class ActivityView extends ActivityBase implements FragmentManager.OnBack
 
     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
-        if (resultCode == Activity.RESULT_OK) {
+        if (resultCode == Activity.RESULT_OK && requestCode > REQUEST_ATTACHMENT_OFFSET) {
             Bundle args = new Bundle();
-            args.putLong("id", requestCode);
+            args.putLong("id", requestCode - REQUEST_ATTACHMENT_OFFSET);
             args.putParcelable("uri", data.getData());
             new SimpleTask<Void>() {
                 @Override

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

@@ -453,6 +453,7 @@ public class FragmentAccount extends FragmentEx {
                             account.password = password;
                             account.synchronize = synchronize;
                             account.primary = (account.synchronize && primary);
+                            account.store_sent = false;
                             account.poll_interval = Integer.parseInt(poll_interval);
 
                             if (!synchronize)

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.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
@@ -54,7 +55,13 @@ 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.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
@@ -110,8 +117,27 @@ public class FragmentCompose extends FragmentEx {
     private boolean addresses;
     private boolean autosave = true;
 
+    private String encrypted = null;
+    private OpenPgpServiceConnection openPgpConnection = null;
+
     private static final int ATTACHMENT_BUFFER_SIZE = 8192; // bytes
 
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        openPgpConnection = new OpenPgpServiceConnection(getContext(), "org.sufficientlysecure.keychain");
+        openPgpConnection.bindToService();
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        if (openPgpConnection != null) {
+            openPgpConnection.unbindFromService();
+            openPgpConnection = null;
+        }
+    }
+
     @Override
     @Nullable
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
@@ -317,6 +343,7 @@ public class FragmentCompose extends FragmentEx {
     public void onSaveInstanceState(Bundle outState) {
         super.onSaveInstanceState(outState);
         outState.putLong("working", working);
+        outState.putString("encrypted", encrypted);
     }
 
     @Override
@@ -337,6 +364,8 @@ public class FragmentCompose extends FragmentEx {
             args.putParcelableArrayList("attachments", getArguments().getParcelableArrayList("attachments"));
             draftLoader.load(this, args);
         } else {
+            encrypted = savedInstanceState.getString("encrypted");
+
             Bundle args = new Bundle();
             args.putString("action", "edit");
             args.putLong("id", savedInstanceState.getLong("working"));
@@ -365,6 +394,7 @@ public class FragmentCompose extends FragmentEx {
         menu.findItem(R.id.menu_attachment).setVisible(!free && working >= 0);
         menu.findItem(R.id.menu_attachment).setEnabled(etBody.isEnabled());
         menu.findItem(R.id.menu_addresses).setVisible(!free && working >= 0);
+        menu.findItem(R.id.menu_encrypt).setVisible(encrypted == null);
     }
 
     @Override
@@ -376,6 +406,9 @@ public class FragmentCompose extends FragmentEx {
             case R.id.menu_addresses:
                 onMenuAddresses();
                 return true;
+            case R.id.menu_encrypt:
+                onMenuEncrypt();
+                return true;
             default:
                 return super.onOptionsItemSelected(item);
         }
@@ -392,12 +425,77 @@ public class FragmentCompose extends FragmentEx {
         grpAddresses.setVisibility(grpAddresses.getVisibility() == View.GONE ? View.VISIBLE : View.GONE);
     }
 
+    private void onMenuEncrypt() {
+        Log.i(Helper.TAG, "On encrypt");
+        try {
+            if (openPgpConnection == null)
+                throw new IllegalArgumentException();
+            if (!openPgpConnection.isBound())
+                throw new IllegalArgumentException("OpenPgp not available");
+
+            EntityIdentity identity = (EntityIdentity) spFrom.getSelectedItem();
+            if (identity == null)
+                throw new IllegalArgumentException("No identity selected");
+
+            Intent data = new Intent();
+            data.setAction(OpenPgpApi.ACTION_ENCRYPT);
+            data.putExtra(OpenPgpApi.EXTRA_USER_IDS, new String[]{identity.email});
+            data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+            String plain = etBody.getText().toString();
+            final InputStream is = new ByteArrayInputStream(plain.getBytes("UTF-8"));
+            final ByteArrayOutputStream os = new ByteArrayOutputStream();
+
+            OpenPgpApi api = new OpenPgpApi(getContext(), openPgpConnection.getService());
+            api.executeApiAsync(data, is, os, new OpenPgpApi.IOpenPgpCallback() {
+                @Override
+                public void onReturn(Intent result) {
+                    try {
+                        int code = result.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR);
+                        switch (code) {
+                            case OpenPgpApi.RESULT_CODE_SUCCESS: {
+                                Log.i(Helper.TAG, "Encrypted");
+                                FragmentCompose.this.encrypted = os.toString("UTF-8");
+                                getActivity().invalidateOptionsMenu();
+                                etBody.setText(FragmentCompose.this.encrypted);
+                                break;
+                            }
+                            case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED: {
+                                Log.i(Helper.TAG, "User interaction");
+                                PendingIntent pi = result.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+                                getActivity().startIntentSenderForResult(
+                                        pi.getIntentSender(),
+                                        ActivityCompose.REQUEST_OPENPGP,
+                                        null, 0, 0, 0);
+                                break;
+                            }
+                            case OpenPgpApi.RESULT_CODE_ERROR: {
+                                OpenPgpError error = result.getParcelableExtra(OpenPgpApi.RESULT_ERROR);
+                                Log.e(Helper.TAG, error.getMessage());
+                                Toast.makeText(getContext(), error.getMessage(), Toast.LENGTH_LONG).show();
+                            }
+                        }
+                    } catch (Throwable ex) {
+                        Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                        Toast.makeText(getContext(), ex.toString(), Toast.LENGTH_LONG).show();
+                    }
+                }
+            });
+        } catch (Throwable ex) {
+            Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+            Toast.makeText(getContext(), ex.toString(), Toast.LENGTH_LONG).show();
+        }
+    }
+
     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
         if (resultCode == RESULT_OK) {
             if (requestCode == ActivityCompose.REQUEST_ATTACHMENT) {
                 if (data != null)
                     handleAddAttachment(data);
+            } else if (requestCode == ActivityCompose.REQUEST_OPENPGP) {
+                Log.i(Helper.TAG, "User interacted");
+                onMenuEncrypt();
             } else
                 handlePickContact(requestCode, data);
         }
@@ -531,7 +629,6 @@ public class FragmentCompose extends FragmentEx {
             if (attachment.type == null)
                 attachment.type = "application/octet-stream";
 
-
             attachment.size = (s == null ? null : Integer.parseInt(s));
             attachment.progress = 0;
 
@@ -903,7 +1000,11 @@ public class FragmentCompose extends FragmentEx {
                 draft.subject = subject;
                 draft.received = new Date().getTime();
 
-                String pbody = "<pre>" + body.replaceAll("\\r?\\n", "<br />") + "</pre>";
+                String pbody;
+                if (encrypted == null)
+                    pbody = "<pre>" + body.replaceAll("\\r?\\n", "<br />") + "</pre>";
+                else
+                    pbody = encrypted;
 
                 // Execute action
                 if (action == R.id.action_trash) {

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

@@ -19,6 +19,7 @@ package eu.faircode.email;
     Copyright 2018 by Marcel Bokhorst (M66B)
 */
 
+import android.app.PendingIntent;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
@@ -55,8 +56,13 @@ import android.widget.Toast;
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 import com.google.android.material.floatingactionbutton.FloatingActionButton;
 
+import org.openintents.openpgp.OpenPgpError;
+import org.openintents.openpgp.util.OpenPgpApi;
+import org.openintents.openpgp.util.OpenPgpServiceConnection;
 import org.xml.sax.XMLReader;
 
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
@@ -73,6 +79,8 @@ import java.util.Date;
 import java.util.List;
 import java.util.Locale;
 
+import javax.mail.internet.InternetAddress;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AlertDialog;
@@ -86,6 +94,8 @@ import androidx.localbroadcastmanager.content.LocalBroadcastManager;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
+import static android.app.Activity.RESULT_OK;
+
 public class FragmentMessage extends FragmentEx {
     private ViewGroup view;
     private TextView tvFrom;
@@ -116,11 +126,30 @@ public class FragmentMessage extends FragmentEx {
     private boolean free = false;
     private AdapterAttachment adapter;
 
+    private String decrypted = null;
+    private OpenPgpServiceConnection openPgpConnection = null;
+
     private boolean debug;
     private DateFormat df = SimpleDateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT);
 
     private static final long CACHE_IMAGE_DURATION = 24 * 3600 * 1000L;
 
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        openPgpConnection = new OpenPgpServiceConnection(getContext(), "org.sufficientlysecure.keychain");
+        openPgpConnection.bindToService();
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        if (openPgpConnection != null) {
+            openPgpConnection.unbindFromService();
+            openPgpConnection = null;
+        }
+    }
+
     @Override
     @Nullable
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
@@ -611,6 +640,7 @@ public class FragmentMessage extends FragmentEx {
         menu.findItem(R.id.menu_seen).setVisible(!free && message != null && !inOutbox);
         menu.findItem(R.id.menu_forward).setVisible(!free && message != null && !inOutbox);
         menu.findItem(R.id.menu_reply_all).setVisible(!free && message != null && message.cc != null && !inOutbox);
+        menu.findItem(R.id.menu_decrypt).setVisible(decrypted == null);
 
         if (message != null) {
             MenuItem menuSeen = menu.findItem(R.id.menu_seen);
@@ -639,6 +669,9 @@ public class FragmentMessage extends FragmentEx {
             case R.id.menu_reply_all:
                 onMenuReplyAll(message.id);
                 return true;
+            case R.id.menu_decrypt:
+                onMenuDecrypt(message);
+                return true;
             default:
                 return super.onOptionsItemSelected(item);
         }
@@ -719,6 +752,75 @@ public class FragmentMessage extends FragmentEx {
                 .putExtra("reference", id));
     }
 
+    private void onMenuDecrypt(EntityMessage message) {
+        Log.i(Helper.TAG, "On decrypt");
+        try {
+            if (openPgpConnection == null)
+                throw new IllegalArgumentException();
+            if (!openPgpConnection.isBound())
+                throw new IllegalArgumentException("OpenPgp not available");
+
+            InternetAddress to = (InternetAddress) message.to[0];
+
+            Intent data = new Intent();
+            data.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
+            data.putExtra(OpenPgpApi.EXTRA_USER_IDS, new String[]{to.getAddress()});
+
+            String encrypted = message.read(getContext());
+            final InputStream is = new ByteArrayInputStream(encrypted.getBytes("UTF-8"));
+            final ByteArrayOutputStream os = new ByteArrayOutputStream();
+
+            OpenPgpApi api = new OpenPgpApi(getContext(), openPgpConnection.getService());
+            api.executeApiAsync(data, is, os, new OpenPgpApi.IOpenPgpCallback() {
+                @Override
+                public void onReturn(Intent result) {
+                    try {
+                        int code = result.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR);
+                        switch (code) {
+                            case OpenPgpApi.RESULT_CODE_SUCCESS: {
+                                Log.i(Helper.TAG, "Decrypted");
+                                FragmentMessage.this.decrypted = os.toString("UTF-8");
+                                getActivity().invalidateOptionsMenu();
+                                tvBody.setText(decrypted);
+                                break;
+                            }
+                            case OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED: {
+                                Log.i(Helper.TAG, "User interaction");
+                                PendingIntent pi = result.getParcelableExtra(OpenPgpApi.RESULT_INTENT);
+                                getActivity().startIntentSenderForResult(
+                                        pi.getIntentSender(),
+                                        ActivityView.REQUEST_OPENPGP,
+                                        null, 0, 0, 0);
+                                break;
+                            }
+                            case OpenPgpApi.RESULT_CODE_ERROR: {
+                                OpenPgpError error = result.getParcelableExtra(OpenPgpApi.RESULT_ERROR);
+                                Log.e(Helper.TAG, error.getMessage());
+                                Toast.makeText(getContext(), error.getMessage(), Toast.LENGTH_LONG).show();
+                            }
+                        }
+                    } catch (Throwable ex) {
+                        Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+                        Toast.makeText(getContext(), ex.toString(), Toast.LENGTH_LONG).show();
+                    }
+                }
+            });
+        } catch (Throwable ex) {
+            Log.e(Helper.TAG, ex + "\n" + Log.getStackTraceString(ex));
+            Toast.makeText(getContext(), ex.toString(), Toast.LENGTH_LONG).show();
+        }
+    }
+
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, Intent data) {
+        if (resultCode == RESULT_OK) {
+            if (requestCode == ActivityView.REQUEST_OPENPGP && message != null) {
+                Log.i(Helper.TAG, "User interacted");
+                onMenuDecrypt(message);
+            }
+        }
+    }
+
     private void onActionSpam(final long id) {
         AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
         builder

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

@@ -13,4 +13,9 @@
         android:icon="@drawable/baseline_people_24"
         android:title="@string/title_show_addresses"
         app:showAsAction="always" />
+
+    <item
+        android:id="@+id/menu_encrypt"
+        android:title="@string/title_encrypt"
+        app:showAsAction="never" />
 </menu>

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

@@ -31,4 +31,9 @@
         android:icon="@drawable/baseline_reply_all_24"
         android:title="@string/title_reply_all"
         app:showAsAction="never" />
+
+    <item
+        android:id="@+id/menu_decrypt"
+        android:title="@string/title_decrypt"
+        app:showAsAction="never" />
 </menu>

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

@@ -160,6 +160,9 @@
     <string name="title_show_addresses">Show CC/BCC</string>
     <string name="title_add_attachment">Add attachment</string>
 
+    <string name="title_encrypt">Encrypt</string>
+    <string name="title_decrypt">Decrypt</string>
+
     <string name="title_from_missing">Sender missing</string>
     <string name="title_to_missing">Recipient missing</string>
     <string name="title_attachments_missing">Attachments still loading</string>