X-Git-Url: http://git.squeep.com/?a=blobdiff_plain;f=lib%2Fpleroma%2Fweb%2Fmedia_proxy%2Fmedia_proxy.ex;h=1b6242cb4d0fa9fad178216094956d9f088145a9;hb=61180ab6f4b85ab78de2eaf1bc1b974c9e7908af;hp=cee6d8481a33942d1d41d51a0cb16ba6fb98ac0b;hpb=e706b42f519fe754af980fc758be492b24e3ccde;p=akkoma diff --git a/lib/pleroma/web/media_proxy/media_proxy.ex b/lib/pleroma/web/media_proxy/media_proxy.ex index cee6d8481..1b6242cb4 100644 --- a/lib/pleroma/web/media_proxy/media_proxy.ex +++ b/lib/pleroma/web/media_proxy/media_proxy.ex @@ -1,91 +1,176 @@ # Pleroma: A lightweight social networking server -# Copyright © 2017-2019 Pleroma Authors +# Copyright © 2017-2020 Pleroma Authors # SPDX-License-Identifier: AGPL-3.0-only defmodule Pleroma.Web.MediaProxy do + alias Pleroma.Config + alias Pleroma.Upload + alias Pleroma.Web + alias Pleroma.Web.MediaProxy.Invalidation + @base64_opts [padding: false] - def url(nil), do: nil + @spec in_banned_urls(String.t()) :: boolean() + def in_banned_urls(url), do: elem(Cachex.exists?(:banned_urls_cache, url(url)), 1) + + def remove_from_banned_urls(urls) when is_list(urls) do + Cachex.execute!(:banned_urls_cache, fn cache -> + Enum.each(Invalidation.prepare_urls(urls), &Cachex.del(cache, &1)) + end) + end + + def remove_from_banned_urls(url) when is_binary(url) do + Cachex.del(:banned_urls_cache, url(url)) + end + + def put_in_banned_urls(urls) when is_list(urls) do + Cachex.execute!(:banned_urls_cache, fn cache -> + Enum.each(Invalidation.prepare_urls(urls), &Cachex.put(cache, &1, true)) + end) + end - def url(""), do: nil + def put_in_banned_urls(url) when is_binary(url) do + Cachex.put(:banned_urls_cache, url(url), true) + end + def url(url) when is_nil(url) or url == "", do: nil def url("/" <> _ = url), do: url def url(url) do - if !enabled?() or local?(url) or whitelisted?(url) do + if not enabled?() or not url_proxiable?(url) do url else encode_url(url) end end - defp enabled?, do: Pleroma.Config.get([:media_proxy, :enabled], false) + @spec url_proxiable?(String.t()) :: boolean() + def url_proxiable?(url) do + if local?(url) or whitelisted?(url) do + false + else + true + end + end + + # Note: routing all URLs to preview handler (even local and whitelisted). + # Preview handler will call url/1 on decoded URLs, and applicable ones will detour media proxy. + def preview_url(url) do + if preview_enabled?() do + encode_preview_url(url) + else + url + end + end + + def enabled?, do: Config.get([:media_proxy, :enabled], false) + + # Note: media proxy must be enabled for media preview proxy in order to load all + # non-local non-whitelisted URLs through it and be sure that body size constraint is preserved. + def preview_enabled?, do: enabled?() and Config.get([:media_preview_proxy, :enabled], false) - defp local?(url), do: String.starts_with?(url, Pleroma.Web.base_url()) + def local?(url), do: String.starts_with?(url, Pleroma.Web.base_url()) - defp whitelisted?(url) do + def whitelisted?(url) do %{host: domain} = URI.parse(url) - Enum.any?(Pleroma.Config.get([:media_proxy, :whitelist]), fn pattern -> + mediaproxy_whitelist = Config.get([:media_proxy, :whitelist]) + + upload_base_url_domain = + if !is_nil(Config.get([Upload, :base_url])) do + [URI.parse(Config.get([Upload, :base_url])).host] + else + [] + end + + whitelist = mediaproxy_whitelist ++ upload_base_url_domain + + Enum.any?(whitelist, fn pattern -> String.equivalent?(domain, pattern) end) end - def encode_url(url) do - secret = Pleroma.Config.get([Pleroma.Web.Endpoint, :secret_key_base]) + defp base64_sig64(url) do + 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") + sig64 = + base64 + |> signed_url() |> Base.url_encode64(@base64_opts) - sig = :crypto.hmac(:sha, secret, base64) - sig64 = sig |> Base.url_encode64(@base64_opts) + {base64, sig64} + end + + def encode_url(url) do + {base64, sig64} = base64_sig64(url) build_url(sig64, base64, filename(url)) end - def decode_url(sig, url) do - secret = Pleroma.Config.get([Pleroma.Web.Endpoint, :secret_key_base]) - sig = Base.url_decode64!(sig, @base64_opts) - local_sig = :crypto.hmac(:sha, secret, url) + def encode_preview_url(url) do + {base64, sig64} = base64_sig64(url) - if local_sig == sig do + build_preview_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} + _ -> {: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 + defp proxy_url(path, sig_base64, url_base64, filename) do [ - Pleroma.Config.get([:media_proxy, :base_url], Pleroma.Web.base_url()), - "proxy", + Pleroma.Config.get([:media_proxy, :base_url], Web.base_url()), + path, sig_base64, url_base64, filename ] - |> Enum.filter(fn value -> value end) + |> Enum.filter(& &1) |> Path.join() end - defp get_replacement(url, replacement) do - if String.contains?(url, replacement) do - get_replacement(url, replacement <> replacement) + def build_url(sig_base64, url_base64, filename \\ nil) do + proxy_url("proxy", sig_base64, url_base64, filename) + end + + def build_preview_url(sig_base64, url_base64, filename \\ nil) do + proxy_url("proxy/preview", sig_base64, url_base64, filename) + end + + def verify_request_path_and_url( + %Plug.Conn{params: %{"filename" => _}, request_path: request_path}, + url + ) do + verify_request_path_and_url(request_path, url) + end + + def verify_request_path_and_url(request_path, url) when is_binary(request_path) do + filename = filename(url) + + if filename && not basename_matches?(request_path, filename) do + {:wrong_filename, filename} else - replacement + :ok end end + + def verify_request_path_and_url(_, _), do: :ok + + defp basename_matches?(path, filename) do + basename = Path.basename(path) + basename == filename or URI.decode(basename) == filename or URI.encode(basename) == filename + end end