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

300 lines
9.1 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.Repo
alias Pleroma.Instances
alias Pleroma.Web.Websub.{WebsubServerSubscription, WebsubClientSubscription}
alias Pleroma.Web.OStatus.FeedRepresenter
alias Pleroma.Web.{XML, Endpoint, OStatus}
alias Pleroma.Web.Router.Helpers
require Logger
import Ecto.Query
@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 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 = Instances.filter_reachable(callbacks)
subscriptions
|> Enum.filter(&(&1.callback in reachable_callbacks))
|> Enum.each(fn sub ->
data = %{
xml: response,
topic: topic,
callback: sub.callback,
secret: sub.secret
}
Pleroma.Web.Federator.enqueue(:publish_single_websub, data)
end)
end
def publish(_, _, _), do: ""
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)
Pleroma.Web.Federator.enqueue(: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)
preferredUsername = XML.string_from_xpath("/feed/author[1]/poco:preferredUsername", doc)
displayName = 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" => preferredUsername || name,
"name" => displayName || 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 ->
Pleroma.Web.Federator.enqueue(:request_subscription, sub)
end)
end
def publish_one(%{xml: xml, topic: topic, callback: callback, secret: secret}) do
signature = sign(secret || "", xml)
Logger.info(fn -> "Pushing #{topic} to #{callback}" end)
with {:reachable, true} <- {:reachable, Instances.reachable?(callback)},
{:ok, %{status: code}} when code in 200..299 <-
@httpoison.post(
callback,
xml,
[
{"Content-Type", "application/atom+xml"},
{"X-Hub-Signature", "sha1=#{signature}"},
{"referer", Pleroma.Web.Endpoint.url()}
]
) do
Instances.set_reachable(callback)
Logger.info(fn -> "Pushed to #{callback}, code #{code}" end)
{:ok, code}
else
{:reachable, false} ->
Logger.debug(fn -> "Pushing to #{callback} skipped as marked unreachable)" end)
{:error, :noop}
e ->
Instances.set_unreachable(callback)
Logger.debug(fn -> "Couldn't push to #{callback}, #{inspect(e)}" end)
{:error, e}
end
end
end