Add simple test, localize error messages

filer/admin/clipboardadmin.py

@@ -141,25 +141,35 @@ def ajax_upload(request, folder_id=None):
             # the image gets attached to a folder and saved. We also
             # send the error msg in the JSON and also post the message
             # so that they know what is wrong with the image they uploaded
-            from django.contrib.messages import ERROR, add_message
-            pixels: int = max(1, file_obj.height) * max(1, file_obj.width)
-
+            from django.contrib.messages import ERROR, WARNING, add_message
+            height: int = max(1, file_obj.height)
+            width: int = max(1, file_obj.width)
+            pixels: int = width * height
+            aspect: float = file_obj.width / file_obj.height
+            res_x: int = int((FILER_MAX_IMAGE_PIXELS * aspect) ** 0.5)
+            res_y: int = int(res_x / aspect)
             if pixels > 2 * FILER_MAX_IMAGE_PIXELS:
-                msg = (
-                    f"Image size ({pixels} pixels) exceeds limit of {2 * FILER_MAX_IMAGE_PIXELS} "
-                    "pixels, could be decompression bomb DOS attack."
-                )
-
+                msg = _(
+                    "Image size (%(pixels)d pixels) exceeds limit of %(max_pixels)d "
+                    "pixels by a factor of two or more. Resize image to (%(width)d, "
+                    "%(height)d) resolution or lower."
+                ).format(pixels=pixels, max_pixels=FILER_MAX_IMAGE_PIXELS,
+                         width=res_x, height=res_y)
                 message = str(msg)
                 add_message(request, ERROR, message)
                 return JsonResponse({'error': message})
 
             if pixels > FILER_MAX_IMAGE_PIXELS:
-                msg = f"Image size ({pixels} pixels) exceeds limit of {FILER_MAX_IMAGE_PIXELS} pixels, could be decompression bomb DOS attack."
+                msg = _(
+                    "Image size (%(pixels)d pixels) exceeds limit of %(max_pixels)d "
+                    "pixels. Consider resizing image to (%(width)d, %(height)d) resolution "
+                    "or lower."
+                ).format(pixels=pixels, max_pixels=FILER_MAX_IMAGE_PIXELS,
+                         width=res_x, height=res_y)
 
                 message = str(msg)
-                add_message(request, ERROR, message)
-                return JsonResponse({'error': message})
+                add_message(request, WARNING, message)
+                # return JsonResponse({'warning': message})
             file_obj.folder = folder
             file_obj.save()
         else:

tests/test_admin.py

@@ -1,3 +1,4 @@
+import json
 import os
 
 import django
@@ -475,6 +476,28 @@ def test_filer_ajax_upload_file(self):
         self.assertEqual(stored_image.original_filename, self.image_name)
         self.assertEqual(stored_image.mime_type, 'image/jpeg')
 
+    def test_filer_ajax_decompression_bomb(self):
+        from filer.admin import clipboardadmin
+        DEFAULT_MAX_IMAGE_PIXELS = clipboardadmin.FILER_MAX_IMAGE_PIXELS
+        clipboardadmin.FILER_MAX_IMAGE_PIXELS = 800 * 200
+        self.assertEqual(Image.objects.count(), 0)
+        folder = Folder.objects.create(name='foo')
+        with open(self.filename, 'rb') as fh:
+            file_obj = django.core.files.File(fh)
+            url = reverse(
+                'admin:filer-ajax_upload',
+                kwargs={'folder_id': folder.pk}
+            ) + '?filename=%s' % self.image_name
+            response = self.client.post(
+                url,
+                data=file_obj.read(),
+                content_type='image/jpeg',
+                **{'HTTP_X_REQUESTED_WITH': 'XMLHttpRequest'}
+            )
+        self.assertEqual(Image.objects.count(), 0)
+        self.assertIn("error", json.loads(response.content.decode("utf-8")))
+        clipboardadmin.FILER_MAX_IMAGE_PIXELS = DEFAULT_MAX_IMAGE_PIXELS
+
     def test_filer_ajax_upload_file_using_content_type(self):
         self.assertEqual(Image.objects.count(), 0)
         folder = Folder.objects.create(name='foo')