From cd13fa17fd8d2c959b4a257a3bdcf52e7f61ddf2 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Sun, 16 Sep 2018 02:07:01 +0000
Subject: [PATCH 1/3] html: allow scrubbing policies to be stackable

---
 lib/pleroma/html.ex | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/pleroma/html.ex b/lib/pleroma/html.ex
index a0c43b82c..1eb0fdc00 100644
--- a/lib/pleroma/html.ex
+++ b/lib/pleroma/html.ex
@@ -3,13 +3,24 @@ defmodule Pleroma.HTML do
 
   @markup Application.get_env(:pleroma, :markup)
 
+  defp get_scrubbers(scrubber) when is_atom(scrubber), do: [scrubber]
+  defp get_scrubbers(scrubbers) when is_list(scrubbers), do: scrubbers
+  defp get_scrubbers(_), do: [Pleroma.HTML.Scrubber.Default]
+
+  def get_scrubbers() do
+    Keyword.get(@markup, :scrub_policy)
+    |> get_scrubbers
+  end
+
   def filter_tags(html, scrubber) do
     html |> Scrubber.scrub(scrubber)
   end
 
   def filter_tags(html) do
-    scrubber = Keyword.get(@markup, :scrub_policy)
-    filter_tags(html, scrubber)
+    get_scrubbers()
+    |> Enum.reduce(html, fn scrubber, html ->
+      filter_tags(html, scrubber)
+    end)
   end
 
   def strip_tags(html) do

From a7d0ecdc7c901476f064a9d9fbad639742d3b509 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Sun, 16 Sep 2018 02:07:32 +0000
Subject: [PATCH 2/3] html: add policy which transforms inline images to pass
 through the media proxy

---
 lib/pleroma/html.ex | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/lib/pleroma/html.ex b/lib/pleroma/html.ex
index 1eb0fdc00..ab62dd1da 100644
--- a/lib/pleroma/html.ex
+++ b/lib/pleroma/html.ex
@@ -142,3 +142,34 @@ defmodule Pleroma.HTML.Scrubber.Default do
 
   Meta.strip_everything_not_covered()
 end
+
+defmodule Pleroma.HTML.Transform.MediaProxy do
+  @moduledoc "Transforms inline image URIs to use MediaProxy."
+
+  alias Pleroma.Web.MediaProxy
+
+  def before_scrub(html), do: html
+
+  def scrub_attribute("img", {"src", "http" <> target}) do
+    media_url =
+      ("http" <> target)
+      |> MediaProxy.url()
+
+    {"src", media_url}
+  end
+
+  def scrub_attribute(tag, attribute), do: attribute
+
+  def scrub({"img", attributes, children}) do
+    attributes =
+      attributes
+      |> Enum.map(fn attr -> scrub_attribute("img", attr) end)
+      |> Enum.reject(&is_nil(&1))
+
+    {"img", attributes, children}
+  end
+
+  def scrub({tag, attributes, children}), do: {tag, attributes, children}
+  def scrub({tag, children}), do: children
+  def scrub(text), do: text
+end

From 5acfa2e0919f459beae6ada55d087db8a74949e1 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Sun, 16 Sep 2018 02:13:54 +0000
Subject: [PATCH 3/3] config: pass inline images through mediaproxy (closes
 #275)

---
 config/config.exs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/config/config.exs b/config/config.exs
index d8edc4862..2290119f7 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -83,7 +83,10 @@ config :pleroma, :markup,
   allow_headings: false,
   allow_tables: false,
   allow_fonts: false,
-  scrub_policy: Pleroma.HTML.Scrubber.Default
+  scrub_policy: [
+    Pleroma.HTML.Transform.MediaProxy,
+    Pleroma.HTML.Scrubber.Default
+  ]
 
 config :pleroma, :fe,
   theme: "pleroma-dark",