git.squeep.com Git - akkoma/blob - lib/pleroma/web/websub/websub.ex

   1 defmodule Pleroma.Web.Websub do
   2   alias Ecto.Changeset
   3   alias Pleroma.Repo
   4   alias Pleroma.Web.Websub.WebsubServerSubscription
   5   alias Pleroma.Web.OStatus.FeedRepresenter
   6   alias Pleroma.Web.OStatus
   7
   8   import Ecto.Query
   9
  10   @websub_verifier Application.get_env(:pleroma, :websub_verifier)
  11
  12   def verify(subscription, getter \\ &HTTPoison.get/3) do
  13     challenge = Base.encode16(:crypto.strong_rand_bytes(8))
  14     lease_seconds = NaiveDateTime.diff(subscription.valid_until, subscription.updated_at)
  15     lease_seconds = lease_seconds |> to_string
  16
  17     params = %{
  18       "hub.challenge": challenge,
  19       "hub.lease_seconds": lease_seconds,
  20       "hub.topic": subscription.topic,
  21       "hub.mode": "subscribe"
  22     }
  23
  24     url = hd(String.split(subscription.callback, "?"))
  25     query = URI.parse(subscription.callback).query || ""
  26     params = Map.merge(params, URI.decode_query(query))
  27     with {:ok, response} <- getter.(url, [], [params: params]),
  28          ^challenge <- response.body
  29     do
  30       changeset = Changeset.change(subscription, %{state: "active"})
  31       Repo.update(changeset)
  32     else _e ->
  33       changeset = Changeset.change(subscription, %{state: "rejected"})
  34       {:ok, subscription} = Repo.update(changeset)
  35       {:error, subscription}
  36     end
  37   end
  38
  39   def publish(topic, user, activity) do
  40     query = from sub in WebsubServerSubscription,
  41     where: sub.topic == ^topic and sub.state == "active"
  42     subscriptions = Repo.all(query)
  43     Enum.each(subscriptions, fn(sub) ->
  44       response = user
  45       |> FeedRepresenter.to_simple_form([activity], [user])
  46       |> :xmerl.export_simple(:xmerl_xml)
  47
  48       signature = Base.encode16(:crypto.hmac(:sha, sub.secret, response))
  49
  50       HTTPoison.post(sub.callback, response, [
  51             {"Content-Type", "application/atom+xml"},
  52             {"X-Hub-Signature", "sha1=#{signature}"}
  53           ])
  54     end)
  55   end
  56
  57   def incoming_subscription_request(user, %{"hub.mode" => "subscribe"} = params) do
  58     with {:ok, topic} <- valid_topic(params, user),
  59          {:ok, lease_time} <- lease_time(params),
  60          secret <- params["hub.secret"],
  61          callback <- params["hub.callback"]
  62     do
  63       subscription = get_subscription(topic, callback)
  64       data = %{
  65         state: subscription.state || "requested",
  66         topic: topic,
  67         secret: secret,
  68         callback: callback
  69       }
  70
  71       change = Changeset.change(subscription, data)
  72       websub = Repo.insert_or_update!(change)
  73
  74       change = Changeset.change(websub, %{valid_until:
  75                                           NaiveDateTime.add(websub.updated_at, lease_time)})
  76       websub = Repo.update!(change)
  77
  78       # Just spawn that for now, maybe pool later.
  79       spawn(fn -> @websub_verifier.verify(websub) end)
  80
  81       {:ok, websub}
  82     else {:error, reason} ->
  83       {:error, reason}
  84     end
  85   end
  86
  87   defp get_subscription(topic, callback) do
  88     Repo.get_by(WebsubServerSubscription, topic: topic, callback: callback) ||
  89       %WebsubServerSubscription{}
  90   end
  91
  92   defp lease_time(%{"hub.lease_seconds" => lease_seconds}) do
  93     {:ok, String.to_integer(lease_seconds)}
  94   end
  95
  96   defp lease_time(_) do
  97     {:ok, 60 * 60 * 24 * 3} # three days
  98   end
  99
 100   defp valid_topic(%{"hub.topic" => topic}, user) do
 101     if topic == OStatus.feed_path(user) do
 102       {:ok, topic}
 103     else
 104       {:error, "Wrong topic requested, expected #{OStatus.feed_path(user)}, got #{topic}"}
 105     end
 106   end
 107 end