git.squeep.com Git - akkoma/blob - lib/pleroma/web/media_proxy/controller.ex

   1 # Pleroma: A lightweight social networking server
   2 # Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
   3 # SPDX-License-Identifier: AGPL-3.0-only
   4
   5 defmodule Pleroma.Web.MediaProxy.MediaProxyController do
   6   use Pleroma.Web, :controller
   7   alias Pleroma.{Web.MediaProxy, ReverseProxy}
   8
   9   @default_proxy_opts [max_body_length: 25 * 1_048_576, http: [follow_redirect: true]]
  10
  11   def remote(conn, params = %{"sig" => sig64, "url" => url64}) do
  12     with config <- Pleroma.Config.get([:media_proxy], []),
  13          true <- Keyword.get(config, :enabled, false),
  14          {:ok, url} <- MediaProxy.decode_url(sig64, url64),
  15          :ok <- filename_matches(Map.has_key?(params, "filename"), conn.request_path, url) do
  16       ReverseProxy.call(conn, url, Keyword.get(config, :proxy_opts, @default_proxy_opts))
  17     else
  18       false ->
  19         send_resp(conn, 404, Plug.Conn.Status.reason_phrase(404))
  20
  21       {:error, :invalid_signature} ->
  22         send_resp(conn, 403, Plug.Conn.Status.reason_phrase(403))
  23
  24       {:wrong_filename, filename} ->
  25         redirect(conn, external: MediaProxy.build_url(sig64, url64, filename))
  26     end
  27   end
  28
  29   def filename_matches(has_filename, path, url) do
  30     filename =
  31       url
  32       |> MediaProxy.filename()
  33       |> URI.decode()
  34
  35     path = URI.decode(path)
  36
  37     if has_filename && filename && Path.basename(path) != filename do
  38       {:wrong_filename, filename}
  39     else
  40       :ok
  41     end
  42   end
  43 end