Merge branch 'feature/jobs' into 'develop'

[akkoma] / lib / pleroma / web / media_proxy / media_proxy.ex

diff --git a/lib/pleroma/web/media_proxy/media_proxy.ex b/lib/pleroma/web/media_proxy/media_proxy.ex
index 93c36b4ed3668f15634bed6c49402772c436a418..39a725a6941c86c61ae69d18657772ad7fb61c43 100644 (file)
--- a/lib/pleroma/web/media_proxy/media_proxy.ex
+++ b/lib/pleroma/web/media_proxy/media_proxy.ex
@@ -1,9 +1,15 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Pleroma.Web.MediaProxy do
   @base64_opts [padding: false]
 
   def url(nil), do: nil
 
-  def url(url = "/" <> _), do: url
+  def url(""), do: nil
+
+  def url("/" <> _ = url), do: url
 
   def url(url) do
     config = Application.get_env(:pleroma, :media_proxy, [])
@@ -12,13 +18,23 @@ defmodule Pleroma.Web.MediaProxy do
       url
     else
       secret = Application.get_env(:pleroma, Pleroma.Web.Endpoint)[:secret_key_base]
-      base64 = Base.url_encode64(url, @base64_opts)
+
+      # Must preserve `%2F` for compatibility with S3 (https://git.pleroma.social/pleroma/pleroma/issues/580)
+      replacement = get_replacement(url, ":2F:")
+
+      # The URL is url-decoded and encoded again to ensure it is correctly encoded and not twice.
+      base64 =
+        url
+        |> String.replace("%2F", replacement)
+        |> URI.decode()
+        |> URI.encode()
+        |> String.replace(replacement, "%2F")
+        |> Base.url_encode64(@base64_opts)
+
       sig = :crypto.hmac(:sha, secret, base64)
       sig64 = sig |> Base.url_encode64(@base64_opts)
-      filename = Path.basename(URI.parse(url).path)
 
-      Keyword.get(config, :base_url, Pleroma.Web.base_url()) <>
-        "/proxy/#{sig64}/#{base64}/#{filename}"
+      build_url(sig64, base64, filename(url))
     end
   end
 
@@ -33,4 +49,28 @@ defmodule Pleroma.Web.MediaProxy do
       {:error, :invalid_signature}
     end
   end
+
+  def filename(url_or_path) do
+    if path = URI.parse(url_or_path).path, do: Path.basename(path)
+  end
+
+  def build_url(sig_base64, url_base64, filename \\ nil) do
+    [
+      Pleroma.Config.get([:media_proxy, :base_url], Pleroma.Web.base_url()),
+      "proxy",
+      sig_base64,
+      url_base64,
+      filename
+    ]
+    |> Enum.filter(fn value -> value end)
+    |> Path.join()
+  end
+
+  defp get_replacement(url, replacement) do
+    if String.contains?(url, replacement) do
+      get_replacement(url, replacement <> replacement)
+    else
+      replacement
+    end
+  end
 end