akkoma/lib/pleroma/web/activity_pub/mrf/simple_policy.ex

324 lines
9.8 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Web.ActivityPub.MRF.SimplePolicy do
@moduledoc "Filter activities depending on their origin instance"
@behaviour Pleroma.Web.ActivityPub.MRF
alias Pleroma.Config
alias Pleroma.FollowingRelationship
alias Pleroma.User
alias Pleroma.Web.ActivityPub.MRF
require Pleroma.Constants
defp check_accept(%{host: actor_host} = _actor_info, object) do
accepts =
Config.get([:mrf_simple, :accept])
|> MRF.subdomains_regex()
cond do
accepts == [] -> {:ok, object}
actor_host == Config.get([Pleroma.Web.Endpoint, :url, :host]) -> {:ok, object}
MRF.subdomain_match?(accepts, actor_host) -> {:ok, object}
true -> {:reject, "[SimplePolicy] host not in accept list"}
end
end
defp check_reject(%{host: actor_host} = _actor_info, object) do
rejects =
Config.get([:mrf_simple, :reject])
|> MRF.subdomains_regex()
if MRF.subdomain_match?(rejects, actor_host) do
{:reject, "[SimplePolicy] host in reject list"}
else
{:ok, object}
end
end
defp check_media_removal(
%{host: actor_host} = _actor_info,
%{"type" => "Create", "object" => %{"attachment" => child_attachment}} = object
)
when length(child_attachment) > 0 do
media_removal =
Config.get([:mrf_simple, :media_removal])
|> MRF.subdomains_regex()
object =
if MRF.subdomain_match?(media_removal, actor_host) do
child_object = Map.delete(object["object"], "attachment")
Map.put(object, "object", child_object)
else
object
end
{:ok, object}
end
defp check_media_removal(_actor_info, object), do: {:ok, object}
defp check_media_nsfw(
%{host: actor_host} = _actor_info,
%{
"type" => "Create",
"object" => child_object
} = object
)
when is_map(child_object) do
media_nsfw =
Config.get([:mrf_simple, :media_nsfw])
|> MRF.subdomains_regex()
object =
if MRF.subdomain_match?(media_nsfw, actor_host) do
child_object =
child_object
|> Map.put("tag", (child_object["tag"] || []) ++ ["nsfw"])
|> Map.put("sensitive", true)
Map.put(object, "object", child_object)
else
object
end
{:ok, object}
end
defp check_media_nsfw(_actor_info, object), do: {:ok, object}
defp check_ftl_removal(%{host: actor_host} = _actor_info, object) do
timeline_removal =
Config.get([:mrf_simple, :federated_timeline_removal])
|> MRF.subdomains_regex()
object =
with true <- MRF.subdomain_match?(timeline_removal, actor_host),
user <- User.get_cached_by_ap_id(object["actor"]),
true <- Pleroma.Constants.as_public() in object["to"] do
to = List.delete(object["to"], Pleroma.Constants.as_public()) ++ [user.follower_address]
cc = List.delete(object["cc"], user.follower_address) ++ [Pleroma.Constants.as_public()]
object
|> Map.put("to", to)
|> Map.put("cc", cc)
else
_ -> object
end
{:ok, object}
end
defp intersection(list1, list2) do
list1 -- list1 -- list2
end
defp check_followers_only(%{host: actor_host} = _actor_info, object) do
followers_only =
Config.get([:mrf_simple, :followers_only])
|> MRF.subdomains_regex()
object =
with true <- MRF.subdomain_match?(followers_only, actor_host),
user <- User.get_cached_by_ap_id(object["actor"]) do
# Don't use Map.get/3 intentionally, these must not be nil
fixed_to = object["to"] || []
fixed_cc = object["cc"] || []
to = FollowingRelationship.followers_ap_ids(user, fixed_to)
cc = FollowingRelationship.followers_ap_ids(user, fixed_cc)
object
|> Map.put("to", intersection([user.follower_address | to], fixed_to))
|> Map.put("cc", intersection([user.follower_address | cc], fixed_cc))
else
_ -> object
end
{:ok, object}
end
defp check_report_removal(%{host: actor_host} = _actor_info, %{"type" => "Flag"} = object) do
report_removal =
Config.get([:mrf_simple, :report_removal])
|> MRF.subdomains_regex()
if MRF.subdomain_match?(report_removal, actor_host) do
{:reject, "[SimplePolicy] host in report_removal list"}
else
{:ok, object}
end
end
defp check_report_removal(_actor_info, object), do: {:ok, object}
defp check_avatar_removal(%{host: actor_host} = _actor_info, %{"icon" => _icon} = object) do
avatar_removal =
Config.get([:mrf_simple, :avatar_removal])
|> MRF.subdomains_regex()
if MRF.subdomain_match?(avatar_removal, actor_host) do
{:ok, Map.delete(object, "icon")}
else
{:ok, object}
end
end
defp check_avatar_removal(_actor_info, object), do: {:ok, object}
defp check_banner_removal(%{host: actor_host} = _actor_info, %{"image" => _image} = object) do
banner_removal =
Config.get([:mrf_simple, :banner_removal])
|> MRF.subdomains_regex()
if MRF.subdomain_match?(banner_removal, actor_host) do
{:ok, Map.delete(object, "image")}
else
{:ok, object}
end
end
defp check_banner_removal(_actor_info, object), do: {:ok, object}
@impl true
def filter(%{"type" => "Delete", "actor" => actor} = object) do
%{host: actor_host} = URI.parse(actor)
reject_deletes =
Config.get([:mrf_simple, :reject_deletes])
|> MRF.subdomains_regex()
if MRF.subdomain_match?(reject_deletes, actor_host) do
{:reject, "[SimplePolicy] host in reject_deletes list"}
else
{:ok, object}
end
end
@impl true
def filter(%{"actor" => actor} = object) do
actor_info = URI.parse(actor)
with {:ok, object} <- check_accept(actor_info, object),
{:ok, object} <- check_reject(actor_info, object),
{:ok, object} <- check_media_removal(actor_info, object),
{:ok, object} <- check_media_nsfw(actor_info, object),
{:ok, object} <- check_ftl_removal(actor_info, object),
{:ok, object} <- check_followers_only(actor_info, object),
{:ok, object} <- check_report_removal(actor_info, object) do
{:ok, object}
else
{:reject, nil} -> {:reject, "[SimplePolicy]"}
{:reject, _} = e -> e
_ -> {:reject, "[SimplePolicy]"}
end
end
def filter(%{"id" => actor, "type" => obj_type} = object)
when obj_type in ["Application", "Group", "Organization", "Person", "Service"] do
actor_info = URI.parse(actor)
with {:ok, object} <- check_accept(actor_info, object),
{:ok, object} <- check_reject(actor_info, object),
{:ok, object} <- check_avatar_removal(actor_info, object),
{:ok, object} <- check_banner_removal(actor_info, object) do
{:ok, object}
else
{:reject, nil} -> {:reject, "[SimplePolicy]"}
{:reject, _} = e -> e
_ -> {:reject, "[SimplePolicy]"}
end
end
def filter(object), do: {:ok, object}
@impl true
def describe do
exclusions = Config.get([:mrf, :transparency_exclusions])
mrf_simple =
Config.get(:mrf_simple)
|> Enum.map(fn {k, v} -> {k, Enum.reject(v, fn v -> v in exclusions end)} end)
|> Enum.into(%{})
{:ok, %{mrf_simple: mrf_simple}}
end
@impl true
def config_description do
%{
key: :mrf_simple,
related_policy: "Pleroma.Web.ActivityPub.MRF.SimplePolicy",
label: "MRF Simple",
description: "Simple ingress policies",
children: [
%{
key: :media_removal,
type: {:list, :string},
description: "List of instances to strip media attachments from",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :media_nsfw,
label: "Media NSFW",
type: {:list, :string},
description: "List of instances to tag all media as NSFW (sensitive) from",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :federated_timeline_removal,
type: {:list, :string},
description:
"List of instances to remove from the Federated (aka The Whole Known Network) Timeline",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :reject,
type: {:list, :string},
description: "List of instances to reject activities from (except deletes)",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :accept,
type: {:list, :string},
description: "List of instances to only accept activities from (except deletes)",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :followers_only,
type: {:list, :string},
description: "Force posts from the given instances to be visible by followers only",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :report_removal,
type: {:list, :string},
description: "List of instances to reject reports from",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :avatar_removal,
type: {:list, :string},
description: "List of instances to strip avatars from",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :banner_removal,
type: {:list, :string},
description: "List of instances to strip banners from",
suggestions: ["example.com", "*.example.com"]
},
%{
key: :reject_deletes,
type: {:list, :string},
description: "List of instances to reject deletions from",
suggestions: ["example.com", "*.example.com"]
}
]
}
end
end