Better encryption support

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

@@ -1218,7 +1218,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
                 // Find encrypted data
                 List<EntityAttachment> attachments = db.attachment().getAttachments(id);
                 for (EntityAttachment attachment : attachments)
-                    if ("encrypted.asc".equals(attachment.name)) {
+                    if (EntityAttachment.PGP_MESSAGE.equals(attachment.encryption)) {
                         if (!attachment.available)
                             throw new IllegalArgumentException(getString(R.string.title_attachments_missing));
 
@@ -1291,7 +1291,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
 
                                 // Remove previously decrypted attachments
                                 for (EntityAttachment a : attachments)
-                                    if (!"encrypted.asc".equals(a.name))
+                                    if (a.encryption == null)
                                         db.attachment().deleteAttachment(a.id);
 
                                 // Add decrypted attachments

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

@@ -128,7 +128,7 @@ public class AdapterAttachment extends RecyclerView.Adapter<AdapterAttachment.Vi
             progressbar.setVisibility(
                     attachment.progress == null || attachment.available ? View.GONE : View.VISIBLE);
 
-            tvType.setText(attachment.type + " " + attachment.cid);
+            tvType.setText(attachment.type + " " + attachment.cid + " " + attachment.encryption);
             tvType.setVisibility(debug ? View.VISIBLE : View.GONE);
         }
 

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

@@ -49,7 +49,7 @@ import io.requery.android.database.sqlite.RequerySQLiteOpenHelperFactory;
 // https://developer.android.com/topic/libraries/architecture/room.html
 
 @Database(
-        version = 29,
+        version = 30,
         entities = {
                 EntityIdentity.class,
                 EntityAccount.class,
@@ -377,6 +377,14 @@ public abstract class DB extends RoomDatabase {
                         db.execSQL("ALTER TABLE `folder` ADD COLUMN `last_sync` INTEGER");
                     }
                 })
+                .addMigrations(new Migration(29, 30) {
+                    @Override
+                    public void migrate(SupportSQLiteDatabase db) {
+                        Log.i("DB migration from version " + startVersion + " to " + endVersion);
+                        db.execSQL("ALTER TABLE `attachment` ADD COLUMN `encryption` INTEGER");
+                        db.execSQL("UPDATE attachment SET encryption = " + EntityAttachment.PGP_MESSAGE + " where name = 'encrypted.asc'");
+                    }
+                })
                 .build();
     }
 

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

@@ -57,6 +57,9 @@ public class EntityAttachment {
     static final String TABLE_NAME = "attachment";
     static final int ATTACHMENT_BUFFER_SIZE = 8192; // bytes
 
+    static final Integer PGP_MESSAGE = 1;
+    static final Integer PGP_SIGNATURE = 2;
+
     @PrimaryKey(autoGenerate = true)
     public Long id;
     @NonNull
@@ -67,8 +70,8 @@ public class EntityAttachment {
     @NonNull
     public String type;
     public String cid; // Content-ID
+    public Integer encryption;
     public Integer size;
-
     public Integer progress;
     @NonNull
     public Boolean available = false;

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

@@ -785,7 +785,7 @@ public class FragmentCompose extends FragmentEx {
                 EntityMessage message = db.message().getMessage(id);
                 List<EntityAttachment> attachments = db.attachment().getAttachments(id);
                 for (EntityAttachment attachment : new ArrayList<>(attachments))
-                    if ("encrypted.asc".equals(attachment.name) || "signature.asc".equals(attachment.name))
+                    if (attachment.encryption != null)
                         attachments.remove(attachment);
 
                 // Build message
@@ -822,7 +822,7 @@ public class FragmentCompose extends FragmentEx {
 
                             // Delete previously encrypted data
                             for (EntityAttachment attachment : db.attachment().getAttachments(id))
-                                if ("encrypted.asc".equals(attachment.name) || "signature.asc".equals(attachment.name))
+                                if (attachment.encryption != null)
                                     db.attachment().deleteAttachment(attachment.id);
 
                             int seq = db.attachment().getAttachmentSequence(id);
@@ -832,6 +832,7 @@ public class FragmentCompose extends FragmentEx {
                             attachment1.sequence = seq + 1;
                             attachment1.name = "encrypted.asc";
                             attachment1.type = "application/octet-stream";
+                            attachment1.encryption = EntityAttachment.PGP_MESSAGE;
                             attachment1.id = db.attachment().insertAttachment(attachment1);
 
                             File file1 = EntityAttachment.getFile(context, attachment1.id);
@@ -856,6 +857,7 @@ public class FragmentCompose extends FragmentEx {
                             attachment2.sequence = seq + 2;
                             attachment2.name = "signature.asc";
                             attachment2.type = "application/octet-stream";
+                            attachment2.encryption = EntityAttachment.PGP_SIGNATURE;
                             attachment2.id = db.attachment().insertAttachment(attachment2);
 
                             File file2 = EntityAttachment.getFile(context, attachment2.id);
@@ -1435,6 +1437,7 @@ public class FragmentCompose extends FragmentEx {
                                 copy.name = attachment.name;
                                 copy.type = attachment.type;
                                 copy.cid = attachment.cid;
+                                copy.encryption = attachment.encryption;
                                 copy.size = attachment.size;
                                 copy.progress = attachment.progress;
                                 copy.available = attachment.available;

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

@@ -218,7 +218,7 @@ public class MessageHelper {
 
         if (message.from != null && message.from.length > 0)
             for (EntityAttachment attachment : attachments)
-                if (attachment.available && "signature.asc".equals(attachment.name)) {
+                if (attachment.available && EntityAttachment.PGP_SIGNATURE.equals(attachment.encryption)) {
                     InternetAddress from = (InternetAddress) message.from[0];
                     File file = EntityAttachment.getFile(context, attachment.id);
                     BufferedReader br = null;
@@ -238,7 +238,7 @@ public class MessageHelper {
                 }
 
         for (final EntityAttachment attachment : attachments)
-            if (attachment.available && "encrypted.asc".equals(attachment.name)) {
+            if (attachment.available && EntityAttachment.PGP_MESSAGE.equals(attachment.encryption)) {
                 Multipart multipart = new MimeMultipart("encrypted; protocol=\"application/pgp-encrypted\"");
 
                 BodyPart pgp = new MimeBodyPart();
@@ -576,9 +576,15 @@ public class MessageHelper {
                 return result;
 
             if (content instanceof Multipart) {
+                boolean pgp = false;
                 Multipart multipart = (Multipart) content;
-                for (int i = 0; i < multipart.getCount(); i++)
+                for (int i = 0; i < multipart.getCount(); i++) {
-                    result.addAll(getAttachments(multipart.getBodyPart(i)));
+                    BodyPart part = multipart.getBodyPart(i);
+                    result.addAll(getAttachments(part, pgp));
+                    ContentType ct = new ContentType(part.getContentType());
+                    if ("application/pgp-encrypted".equals(ct.getBaseType().toLowerCase()))
+                        pgp = true;
+                }
             }
         } catch (IOException ex) {
             if (ex.getCause() instanceof MessagingException)
@@ -592,7 +598,7 @@ public class MessageHelper {
         return result;
     }
 
-    private static List<EntityAttachment> getAttachments(BodyPart part) throws
+    private static List<EntityAttachment> getAttachments(BodyPart part, boolean pgp) throws
             IOException, MessagingException {
         List<EntityAttachment> result = new ArrayList<>();
 
@@ -635,6 +641,7 @@ public class MessageHelper {
                 attachment.type = ct.getBaseType().toLowerCase();
                 attachment.size = part.getSize();
                 attachment.cid = (cid == null || cid.length == 0 ? null : cid[0]);
+                attachment.encryption = (pgp ? EntityAttachment.PGP_MESSAGE : null);
                 attachment.part = part;
 
                 // Try to guess a better content type
@@ -658,8 +665,13 @@ public class MessageHelper {
             }
         } else if (content instanceof Multipart) {
             Multipart multipart = (Multipart) content;
-            for (int i = 0; i < multipart.getCount(); i++)
+            for (int i = 0; i < multipart.getCount(); i++) {
-                result.addAll(getAttachments(multipart.getBodyPart(i)));
+                BodyPart cpart = multipart.getBodyPart(i);
+                result.addAll(getAttachments(cpart, pgp));
+                ContentType ct = new ContentType(cpart.getContentType());
+                if ("application/pgp-encrypted".equals(ct.getBaseType().toLowerCase()))
+                    pgp = true;
+            }
         }
 
         return result;

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

@@ -2436,7 +2436,8 @@ public class ServiceSynchronize extends LifecycleService {
             int sequence = 1;
             for (EntityAttachment attachment : helper.getAttachments()) {
                 Log.i(folder.name + " attachment seq=" + sequence +
-                        " name=" + attachment.name + " type=" + attachment.type + " cid=" + attachment.cid);
+                        " name=" + attachment.name + " type=" + attachment.type +
+                        " cid=" + attachment.cid + " pgp=" + attachment.encryption);
                 if (!TextUtils.isEmpty(attachment.cid) &&
                         db.attachment().getAttachment(message.id, attachment.cid) != null) {
                     Log.i("Skipping duplicated CID");