From 718e8e1edb537aca984216be39b3be5c8af4e6da Mon Sep 17 00:00:00 2001 From: Alex Gleason Date: Sun, 16 May 2021 21:39:58 -0500 Subject: [PATCH] Create NsfwApiPolicy --- config/config.exs | 7 + .../web/activity_pub/mrf/nsfw_api_policy.ex | 185 +++++++++++++++++++++ 2 files changed, 192 insertions(+) create mode 100644 lib/pleroma/web/activity_pub/mrf/nsfw_api_policy.ex diff --git a/config/config.exs b/config/config.exs index 66aee3264..d96dc1646 100644 --- a/config/config.exs +++ b/config/config.exs @@ -404,6 +404,13 @@ config :pleroma, :mrf_object_age, threshold: 604_800, actions: [:delist, :strip_followers] +config :pleroma, :mrf_nsfw_api, + url: "http://127.0.0.1:5000/", + threshold: 0.7, + mark_sensitive: true, + unlist: false, + reject: false + config :pleroma, :rich_media, enabled: true, ignore_hosts: [], diff --git a/lib/pleroma/web/activity_pub/mrf/nsfw_api_policy.ex b/lib/pleroma/web/activity_pub/mrf/nsfw_api_policy.ex new file mode 100644 index 000000000..9ad175b1b --- /dev/null +++ b/lib/pleroma/web/activity_pub/mrf/nsfw_api_policy.ex @@ -0,0 +1,185 @@ +# Pleroma: A lightweight social networking server +# Copyright © 2017-2021 Pleroma Authors +# SPDX-License-Identifier: AGPL-3.0-only + +defmodule Pleroma.Web.ActivityPub.MRF.NsfwApiPolicy do + @moduledoc """ + Hide, delete, or mark sensitive NSFW content with artificial intelligence. + + Requires a NSFW API server, configured like so: + + config :pleroma, Pleroma.Web.ActivityPub.MRF.NsfwMRF, + url: "http://127.0.0.1:5000/", + threshold: 0.8, + mark_sensitive: true, + unlist: false, + reject: false + + The NSFW API server must implement an HTTP endpoint like this: + + curl http://localhost:5000/?url=https://fedi.com/images/001.jpg + + Returning a response like this: + + {"score", 0.314} + + Where a score is 0-1, with `1` being definitely NSFW. + + A good API server is here: https://github.com/EugenCepoi/nsfw_api + You can run it with Docker with a one-liner: + + docker run -it -p 127.0.0.1:5000:5000/tcp --env PORT=5000 eugencepoi/nsfw_api:latest + + Options: + + - `url`: Base URL of the API server. Default: "http://127.0.0.1:5000/" + - `threshold`: Lowest score to take action on. Default: `0.7` + - `mark_sensitive`: Mark sensitive all detected NSFW content? Default: `true` + - `unlist`: Unlist all detected NSFW content? Default: `false` + - `reject`: Reject all detected NSFW content (takes precedence)? Default: `false` + """ + alias Pleroma.Config + alias Pleroma.Constants + alias Pleroma.HTTP + alias Pleroma.User + + require Logger + require Pleroma.Constants + + @behaviour Pleroma.Web.ActivityPub.MRF + @policy :mrf_nsfw_api + + defp build_request_url(url) do + Config.get([@policy, :url]) + |> URI.parse() + |> Map.put(:query, "url=#{url}") + |> URI.to_string() + end + + defp parse_url(url) do + request = build_request_url(url) + + with {:ok, %Tesla.Env{body: body}} <- HTTP.get(request) do + Jason.decode(body) + else + error -> + Logger.warn(""" + [NsfwApiPolicy]: The API server failed. Skipping. + #{inspect(error)} + """) + + error + end + end + + defp check_url_nsfw(url) when is_binary(url) do + threshold = Config.get([@policy, :threshold]) + + case parse_url(url) do + {:ok, %{"score" => score}} when score >= threshold -> + {:nsfw, %{url: url, score: score, threshold: threshold}} + + _ -> + {:sfw, url} + end + end + + defp check_url_nsfw(%{"href" => url}) when is_binary(url) do + check_url_nsfw(url) + end + + defp check_attachment_nsfw(%{"url" => urls} = attachment) when is_list(urls) do + if Enum.all?(urls, &match?({:sfw, _}, check_url_nsfw(&1))) do + {:sfw, attachment} + else + {:nsfw, attachment} + end + end + + defp check_object_nsfw(%{"attachment" => attachments} = object) when is_list(attachments) do + if Enum.all?(attachments, &match?({:sfw, _}, check_attachment_nsfw(&1))) do + {:sfw, object} + else + {:nsfw, object} + end + end + + defp check_object_nsfw(%{"object" => %{} = child_object} = object) do + case check_object_nsfw(child_object) do + {:sfw, _} -> {:sfw, object} + {:nsfw, _} -> {:nsfw, object} + end + end + + defp check_object_nsfw(object), do: {:sfw, object} + + @impl true + def filter(object) do + with {:sfw, object} <- check_object_nsfw(object) do + {:ok, object} + else + {:nsfw, _data} -> handle_nsfw(object) + _ -> {:reject, "NSFW: Attachment rejected"} + end + end + + defp handle_nsfw(object) do + if Config.get([@policy, :reject]) do + {:reject, object} + else + {:ok, + object + |> maybe_unlist() + |> maybe_mark_sensitive()} + end + end + + defp maybe_unlist(object) do + if Config.get([@policy, :unlist]) do + unlist(object) + else + object + end + end + + defp maybe_mark_sensitive(object) do + if Config.get([@policy, :mark_sensitive]) do + mark_sensitive(object) + else + object + end + end + + defp unlist(%{"to" => to, "cc" => cc, "actor" => actor} = object) do + with %User{} = user <- User.get_cached_by_ap_id(actor) do + to = + [user.follower_address | to] + |> List.delete(Constants.as_public()) + |> Enum.uniq() + + cc = + [Constants.as_public() | cc] + |> List.delete(user.follower_address) + |> Enum.uniq() + + object + |> Map.put("to", to) + |> Map.put("cc", cc) + end + end + + defp mark_sensitive(%{"object" => child_object} = object) when is_map(child_object) do + Map.put(object, "object", mark_sensitive(child_object)) + end + + defp mark_sensitive(object) when is_map(object) do + tags = (object["tag"] || []) ++ ["nsfw"] + + object + |> Map.put("tag", tags) + |> Map.put("sensitive", true) + end + + @impl true + def describe, do: {:ok, %{}} +end