defmodule Pleroma.Web.Websub do alias Pleroma.Repo 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 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) |> 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 = Ecto.Changeset.change(subscription, %{state: "active"}) Repo.update(changeset) else _e -> changeset = Ecto.Changeset.change(subscription, %{state: "rejected"}) {:ok, subscription } = Repo.update(changeset) {:error, subscription} end end def publish(topic, user, activity) do query = from sub in WebsubServerSubscription, where: sub.topic == ^topic and sub.state == "active" subscriptions = Repo.all(query) Enum.each(subscriptions, fn(sub) -> response = FeedRepresenter.to_simple_form(user, [activity], [user]) |> :xmerl.export_simple(:xmerl_xml) |> to_string signature = sign(sub.secret, response) HTTPoison.post(sub.callback, response, [ {"Content-Type", "application/atom+xml"}, {"X-Hub-Signature", "sha1=#{signature}"} ]) end) end def sign(secret, doc) do :crypto.hmac(:sha, secret, to_string(doc)) |> Base.encode16 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 = Ecto.Changeset.change(subscription, data) websub = Repo.insert_or_update!(change) change = Ecto.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 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 {:ok, 60 * 60 * 24 * 3} # three days end defp lease_time(%{"hub.lease_seconds" => lease_seconds}) do {:ok, String.to_integer(lease_seconds)} end defp lease_time(_) do {:ok, 60 * 60 * 24 * 3} # three days 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_code when status_code in 200..299 <- response.status_code, 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) {:ok, %{ "uri" => uri, "hub" => hub, "nickname" => preferredUsername || name, "name" => displayName || name, "host" => URI.parse(uri).host, "avatar" => avatar }} 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_code: 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("Couldn't confirm subscription: #{inspect(websub)}") Logger.debug("error: #{inspect(e)}") {:error, websub} end end end