PGP inline support

FAQ.md

@@ -174,7 +174,7 @@ To encrypt a message before sending, just select the menu *Encrypt*. Similarly,
 Encryption is [Autocrypt](https://autocrypt.org/) compatible. For security reasons received messages are not decrypted automatically.
 Encryption/decryption is a pro feature.
 
-Inline PGP is not supported, see [here](https://josefsson.org/inline-openpgp-considered-harmful.html) why not.
+Sending inline PGP encrypted messages is not supported, see [here](https://josefsson.org/inline-openpgp-considered-harmful.html) about why not.
 
 Note that signed only or encrypted only messages are not supported, see here for some considerations:
 

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

@@ -62,6 +62,7 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.FileReader;
+import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.net.URL;
 import java.text.Collator;
@@ -125,6 +126,9 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
     static final String UPDATE_LATEST_API = "https://api.github.com/repos/M66B/open-source-email/releases/latest";
     static final long UPDATE_INTERVAL = 12 * 3600 * 1000L; // milliseconds
 
+    private static final String PGP_BEGIN_MESSAGE = "-----BEGIN PGP MESSAGE-----";
+    private static final String PGP_END_MESSAGE = "-----END PGP MESSAGE-----";
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -976,18 +980,41 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
 
                 DB db = DB.getInstance(context);
 
+                boolean inline = false;
+                InputStream encrypted = null;
+
                 // Find encrypted data
-                boolean found = false;
                 List<EntityAttachment> attachments = db.attachment().getAttachments(id);
                 for (EntityAttachment attachment : attachments)
                     if ("encrypted.asc".equals(attachment.name)) {
                         if (!attachment.available)
                             throw new IllegalArgumentException(getString(R.string.title_attachments_missing));
 
-                        found = true;
+                        encrypted = new FileInputStream(EntityAttachment.getFile(context, attachment.id));
+                        break;
+                    }
+
+                if (encrypted == null) {
+                    EntityMessage message = db.message().getMessage(id);
+                    if (message.content) {
+                        String body = message.read(context);
+                        if (body != null) {
+                            int begin = body.indexOf(PGP_BEGIN_MESSAGE);
+                            int end = body.indexOf(PGP_END_MESSAGE);
+                            if (begin >= 0 && begin < end) {
+                                String section = body.substring(begin, end + PGP_END_MESSAGE.length());
+                                section = section.replace("<br />", "\n\r");
+
+                                inline = true;
+                                encrypted = new ByteArrayInputStream(section.getBytes());
+                            }
+                        }
+                    }
+                }
+
+                if (encrypted == null)
+                    throw new IllegalArgumentException(getString(R.string.title_not_encrypted));
 
-                        // Serialize encrypted data
-                        FileInputStream encrypted = new FileInputStream(EntityAttachment.getFile(context, attachment.id));
                 ByteArrayOutputStream decrypted = new ByteArrayOutputStream();
 
                 // Decrypt message
@@ -995,6 +1022,22 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                 Intent result = api.executeApi(data, encrypted, decrypted);
                 switch (result.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR)) {
                     case OpenPgpApi.RESULT_CODE_SUCCESS:
+                        if (inline) {
+                            try {
+                                db.beginTransaction();
+
+                                // Write decrypted body
+                                EntityMessage m = db.message().getMessage(id);
+                                m.write(context, decrypted.toString());
+
+                                db.message().setMessageStored(id, new Date().getTime());
+
+                                db.setTransactionSuccessful();
+                            } finally {
+                                db.endTransaction();
+                            }
+
+                        } else {
                             // Decode message
                             Properties props = MessageHelper.getSessionProperties(Helper.AUTH_TYPE_PASSWORD, false);
                             Session isession = Session.getInstance(props, null);
@@ -1028,6 +1071,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                             } finally {
                                 db.endTransaction();
                             }
+                        }
 
                         break;
 
@@ -1040,12 +1084,6 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                         throw new IllegalArgumentException(error.getMessage());
                 }
 
-                        break;
-                    }
-
-                if (!found)
-                    throw new IllegalArgumentException(getString(R.string.title_not_encrypted));
-
                 return null;
             }