Use temporary folder for encryption

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

@@ -2320,8 +2320,11 @@ public class FragmentCompose extends FragmentBase {
                     throw new IllegalArgumentException(context.getString(R.string.title_from_missing));
 
                 // Create files
-                File input = new File(context.getCacheDir(), "pgp_input." + draft.id);
-                File output = new File(context.getCacheDir(), "pgp_output." + draft.id);
+                File tmp = new File(context.getFilesDir(), "encryption");
+                if (!tmp.exists())
+                    tmp.mkdir();
+                File input = new File(tmp, draft.id + ".pgp_input");
+                File output = new File(tmp, draft.id + ".pgp_output");
 
                 // Serializing messages is NOT reproducible
                 if ((EntityMessage.PGP_SIGNONLY.equals(draft.ui_encrypt) &&
@@ -2652,6 +2655,10 @@ public class FragmentCompose extends FragmentBase {
                 SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
                 boolean check_certificate = prefs.getBoolean("check_certificate", true);
 
+                File tmp = new File(context.getFilesDir(), "encryption");
+                if (!tmp.exists())
+                    tmp.mkdir();
+
                 DB db = DB.getInstance(context);
 
                 // Get data
@@ -2777,7 +2784,7 @@ public class FragmentCompose extends FragmentBase {
                         .build(contentSigner, chain[0]);
                 cmsGenerator.addSignerInfoGenerator(signerInfoGenerator);
 
-                File sinput = new File(context.getCacheDir(), "smime_sign." + draft.id);
+                File sinput = new File(tmp, draft.id + ".smime_sign");
                 try (FileOutputStream fos = new FileOutputStream(sinput)) {
                     bpContent.writeTo(fos);
                 }
@@ -2895,7 +2902,7 @@ public class FragmentCompose extends FragmentBase {
                     }
                 }
 
-                File einput = new File(context.getCacheDir(), "smime_encrypt." + draft.id);
+                File einput = new File(tmp, draft.id + ".smime_encrypt");
                 try (FileOutputStream fos = new FileOutputStream(einput)) {
                     imessage.writeTo(fos);
                 }

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

@@ -191,6 +191,7 @@ public class WorkerCleanup extends Worker {
             File[] messages = new File(context.getFilesDir(), "messages").listFiles();
             File[] revision = new File(context.getFilesDir(), "revision").listFiles();
             File[] references = new File(context.getFilesDir(), "references").listFiles();
+            File[] encryption = new File(context.getFilesDir(), "encryption").listFiles();
             File[] photos = new File(context.getCacheDir(), "photo").listFiles();
             File[] calendars = new File(context.getCacheDir(), "calendar").listFiles();
 
@@ -200,6 +201,8 @@ public class WorkerCleanup extends Worker {
                 files.addAll(Arrays.asList(revision));
             if (references != null)
                 files.addAll(Arrays.asList(references));
+            if (encryption != null)
+                files.addAll(Arrays.asList(encryption));
             if (photos != null)
                 files.addAll(Arrays.asList(photos));
             if (calendars != null)