akkoma/lib/pleroma/web/websub/websub.ex

332 lines
9.9 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.Websub do
alias Ecto.Changeset
alias Pleroma.Activity
alias Pleroma.Instances
alias Pleroma.Repo
alias Pleroma.User
alias Pleroma.Web.ActivityPub.Visibility
alias Pleroma.Web.Endpoint
alias Pleroma.Web.Federator
alias Pleroma.Web.Federator.Publisher
alias Pleroma.Web.OStatus
alias Pleroma.Web.OStatus.FeedRepresenter
alias Pleroma.Web.Router.Helpers
alias Pleroma.Web.Websub.WebsubClientSubscription
alias Pleroma.Web.Websub.WebsubServerSubscription
alias Pleroma.Web.XML
require Logger
import Ecto.Query
@behaviour Pleroma.Web.Federator.Publisher
@httpoison Application.get_env(:pleroma, :httpoison)
def verify(subscription, getter \\ &@httpoison.get/3) do
challenge = Base.encode16(:crypto.strong_rand_bytes(8))
lease_seconds = NaiveDateTime.diff(subscription.valid_until, subscription.updated_at)
lease_seconds = lease_seconds |> to_string
params = %{
"hub.challenge": challenge,
"hub.lease_seconds": lease_seconds,
"hub.topic": subscription.topic,
"hub.mode": "subscribe"
}
url = hd(String.split(subscription.callback, "?"))
query = URI.parse(subscription.callback).query || ""
params = Map.merge(params, URI.decode_query(query))
with {:ok, response} <- getter.(url, [], params: params),
^challenge <- response.body do
changeset = Changeset.change(subscription, %{state: "active"})
Repo.update(changeset)
else
e ->
Logger.debug("Couldn't verify subscription")
Logger.debug(inspect(e))
{:error, subscription}
end
end
@supported_activities [
"Create",
"Follow",
"Like",
"Announce",
"Undo",
"Delete"
]
def is_representable?(%Activity{data: %{"type" => type}} = activity)
when type in @supported_activities,
do: Visibility.is_public?(activity)
def is_representable?(_), do: false
def publish(topic, user, %{data: %{"type" => type}} = activity)
when type in @supported_activities do
response =
user
|> FeedRepresenter.to_simple_form([activity], [user])
|> :xmerl.export_simple(:xmerl_xml)
|> to_string
query =
from(
sub in WebsubServerSubscription,
where: sub.topic == ^topic and sub.state == "active",
where: fragment("? > (NOW() at time zone 'UTC')", sub.valid_until)
)
subscriptions = Repo.all(query)
callbacks = Enum.map(subscriptions, & &1.callback)
reachable_callbacks_metadata = Instances.filter_reachable(callbacks)
reachable_callbacks = Map.keys(reachable_callbacks_metadata)
subscriptions
|> Enum.filter(&(&1.callback in reachable_callbacks))
|> Enum.each(fn sub ->
data = %{
xml: response,
topic: topic,
callback: sub.callback,
secret: sub.secret,
unreachable_since: reachable_callbacks_metadata[sub.callback]
}
Publisher.enqueue_one(__MODULE__, data)
end)
end
def publish(_, _, _), do: ""
def publish(actor, activity), do: publish(Pleroma.Web.OStatus.feed_path(actor), actor, activity)
def sign(secret, doc) do
:crypto.hmac(:sha, secret, to_string(doc)) |> Base.encode16() |> String.downcase()
end
def incoming_subscription_request(user, %{"hub.mode" => "subscribe"} = params) do
with {:ok, topic} <- valid_topic(params, user),
{:ok, lease_time} <- lease_time(params),
secret <- params["hub.secret"],
callback <- params["hub.callback"] do
subscription = get_subscription(topic, callback)
data = %{
state: subscription.state || "requested",
topic: topic,
secret: secret,
callback: callback
}
change = Changeset.change(subscription, data)
websub = Repo.insert_or_update!(change)
change =
Changeset.change(websub, %{valid_until: NaiveDateTime.add(websub.updated_at, lease_time)})
websub = Repo.update!(change)
Federator.verify_websub(websub)
{:ok, websub}
else
{:error, reason} ->
Logger.debug("Couldn't create subscription")
Logger.debug(inspect(reason))
{:error, reason}
end
end
def incoming_subscription_request(user, params) do
Logger.info("Unhandled WebSub request for #{user.nickname}: #{inspect(params)}")
{:error, "Invalid WebSub request"}
end
defp get_subscription(topic, callback) do
Repo.get_by(WebsubServerSubscription, topic: topic, callback: callback) ||
%WebsubServerSubscription{}
end
# Temp hack for mastodon.
defp lease_time(%{"hub.lease_seconds" => ""}) do
# three days
{:ok, 60 * 60 * 24 * 3}
end
defp lease_time(%{"hub.lease_seconds" => lease_seconds}) do
{:ok, String.to_integer(lease_seconds)}
end
defp lease_time(_) do
# three days
{:ok, 60 * 60 * 24 * 3}
end
defp valid_topic(%{"hub.topic" => topic}, user) do
if topic == OStatus.feed_path(user) do
{:ok, OStatus.feed_path(user)}
else
{:error, "Wrong topic requested, expected #{OStatus.feed_path(user)}, got #{topic}"}
end
end
def subscribe(subscriber, subscribed, requester \\ &request_subscription/1) do
topic = subscribed.info.topic
# FIXME: Race condition, use transactions
{:ok, subscription} =
with subscription when not is_nil(subscription) <-
Repo.get_by(WebsubClientSubscription, topic: topic) do
subscribers = [subscriber.ap_id | subscription.subscribers] |> Enum.uniq()
change = Ecto.Changeset.change(subscription, %{subscribers: subscribers})
Repo.update(change)
else
_e ->
subscription = %WebsubClientSubscription{
topic: topic,
hub: subscribed.info.hub,
subscribers: [subscriber.ap_id],
state: "requested",
secret: :crypto.strong_rand_bytes(8) |> Base.url_encode64(),
user: subscribed
}
Repo.insert(subscription)
end
requester.(subscription)
end
def gather_feed_data(topic, getter \\ &@httpoison.get/1) do
with {:ok, response} <- getter.(topic),
status when status in 200..299 <- response.status,
body <- response.body,
doc <- XML.parse_document(body),
uri when not is_nil(uri) <- XML.string_from_xpath("/feed/author[1]/uri", doc),
hub when not is_nil(hub) <- XML.string_from_xpath(~S{/feed/link[@rel="hub"]/@href}, doc) do
name = XML.string_from_xpath("/feed/author[1]/name", doc)
preferred_username = XML.string_from_xpath("/feed/author[1]/poco:preferredUsername", doc)
display_name = XML.string_from_xpath("/feed/author[1]/poco:displayName", doc)
avatar = OStatus.make_avatar_object(doc)
bio = XML.string_from_xpath("/feed/author[1]/summary", doc)
{:ok,
%{
"uri" => uri,
"hub" => hub,
"nickname" => preferred_username || name,
"name" => display_name || name,
"host" => URI.parse(uri).host,
"avatar" => avatar,
"bio" => bio
}}
else
e ->
{:error, e}
end
end
def request_subscription(websub, poster \\ &@httpoison.post/3, timeout \\ 10_000) do
data = [
"hub.mode": "subscribe",
"hub.topic": websub.topic,
"hub.secret": websub.secret,
"hub.callback": Helpers.websub_url(Endpoint, :websub_subscription_confirmation, websub.id)
]
# This checks once a second if we are confirmed yet
websub_checker = fn ->
helper = fn helper ->
:timer.sleep(1000)
websub = Repo.get_by(WebsubClientSubscription, id: websub.id, state: "accepted")
if websub, do: websub, else: helper.(helper)
end
helper.(helper)
end
task = Task.async(websub_checker)
with {:ok, %{status: 202}} <-
poster.(websub.hub, {:form, data}, "Content-type": "application/x-www-form-urlencoded"),
{:ok, websub} <- Task.yield(task, timeout) do
{:ok, websub}
else
e ->
Task.shutdown(task)
change = Ecto.Changeset.change(websub, %{state: "rejected"})
{:ok, websub} = Repo.update(change)
Logger.debug(fn -> "Couldn't confirm subscription: #{inspect(websub)}" end)
Logger.debug(fn -> "error: #{inspect(e)}" end)
{:error, websub}
end
end
def refresh_subscriptions(delta \\ 60 * 60 * 24) do
Logger.debug("Refreshing subscriptions")
cut_off = NaiveDateTime.add(NaiveDateTime.utc_now(), delta)
query = from(sub in WebsubClientSubscription, where: sub.valid_until < ^cut_off)
subs = Repo.all(query)
Enum.each(subs, fn sub ->
Federator.request_subscription(sub)
end)
end
def publish_one(%{xml: xml, topic: topic, callback: callback, secret: secret} = params) do
signature = sign(secret || "", xml)
Logger.info(fn -> "Pushing #{topic} to #{callback}" end)
with {:ok, %{status: code}} when code in 200..299 <-
@httpoison.post(
callback,
xml,
[
{"Content-Type", "application/atom+xml"},
{"X-Hub-Signature", "sha1=#{signature}"}
]
) do
if !Map.has_key?(params, :unreachable_since) || params[:unreachable_since],
do: Instances.set_reachable(callback)
Logger.info(fn -> "Pushed to #{callback}, code #{code}" end)
{:ok, code}
else
{_post_result, response} ->
unless params[:unreachable_since], do: Instances.set_reachable(callback)
Logger.debug(fn -> "Couldn't push to #{callback}, #{inspect(response)}" end)
{:error, response}
end
end
def gather_webfinger_links(%User{} = user) do
[
%{
"rel" => "http://schemas.google.com/g/2010#updates-from",
"type" => "application/atom+xml",
"href" => OStatus.feed_path(user)
},
%{
"rel" => "http://ostatus.org/schema/1.0/subscribe",
"template" => OStatus.remote_follow_path()
}
]
end
end