74 lines
1.7 KiB
Elixir
74 lines
1.7 KiB
Elixir
# 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
|
|
alias Pleroma.Config
|
|
alias Pleroma.Web
|
|
|
|
@base64_opts [padding: false]
|
|
|
|
def url(url) when is_nil(url) or url == "", do: nil
|
|
def url("/" <> _ = url), do: url
|
|
|
|
def url(url) do
|
|
if disabled?() or local?(url) or whitelisted?(url) do
|
|
url
|
|
else
|
|
encode_url(url)
|
|
end
|
|
end
|
|
|
|
defp disabled?, do: !Config.get([:media_proxy, :enabled], false)
|
|
|
|
defp local?(url), do: String.starts_with?(url, Pleroma.Web.base_url())
|
|
|
|
defp whitelisted?(url) do
|
|
%{host: domain} = URI.parse(url)
|
|
|
|
Enum.any?(Config.get([:media_proxy, :whitelist]), fn pattern ->
|
|
String.equivalent?(domain, pattern)
|
|
end)
|
|
end
|
|
|
|
def encode_url(url) do
|
|
base64 = Base.url_encode64(url, @base64_opts)
|
|
|
|
sig64 =
|
|
base64
|
|
|> signed_url
|
|
|> Base.url_encode64(@base64_opts)
|
|
|
|
build_url(sig64, base64, filename(url))
|
|
end
|
|
|
|
def decode_url(sig, url) do
|
|
with {:ok, sig} <- Base.url_decode64(sig, @base64_opts),
|
|
signature when signature == sig <- signed_url(url) do
|
|
{:ok, Base.url_decode64!(url, @base64_opts)}
|
|
else
|
|
_ -> {:error, :invalid_signature}
|
|
end
|
|
end
|
|
|
|
defp signed_url(url) do
|
|
:crypto.hmac(:sha, Config.get([Web.Endpoint, :secret_key_base]), url)
|
|
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], Web.base_url()),
|
|
"proxy",
|
|
sig_base64,
|
|
url_base64,
|
|
filename
|
|
]
|
|
|> Enum.filter(& &1)
|
|
|> Path.join()
|
|
end
|
|
end
|