1 # Pleroma: A lightweight social networking server
2 # Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
3 # SPDX-License-Identifier: AGPL-3.0-only
5 defmodule Pleroma.Web.Salmon do
6 @behaviour Pleroma.Web.Federator.Publisher
10 alias Pleroma.Activity
12 alias Pleroma.Instances
15 alias Pleroma.Web.ActivityPub.Visibility
16 alias Pleroma.Web.Federator.Publisher
17 alias Pleroma.Web.OStatus
18 alias Pleroma.Web.OStatus.ActivityRepresenter
24 doc = XML.parse_document(salmon)
26 {:xmlObj, :string, data} = :xmerl_xpath.string('string(//me:data[1])', doc)
27 {:xmlObj, :string, sig} = :xmerl_xpath.string('string(//me:sig[1])', doc)
28 {:xmlObj, :string, alg} = :xmerl_xpath.string('string(//me:alg[1])', doc)
29 {:xmlObj, :string, encoding} = :xmerl_xpath.string('string(//me:encoding[1])', doc)
30 {:xmlObj, :string, type} = :xmerl_xpath.string('string(//me:data[1]/@type)', doc)
32 {:ok, data} = Base.url_decode64(to_string(data), ignore: :whitespace)
33 {:ok, sig} = Base.url_decode64(to_string(sig), ignore: :whitespace)
35 encoding = to_string(encoding)
36 type = to_string(type)
38 [data, type, encoding, alg, sig]
41 def fetch_magic_key(salmon) do
42 with [data, _, _, _, _] <- decode(salmon),
43 doc <- XML.parse_document(data),
44 uri when not is_nil(uri) <- XML.string_from_xpath("/entry/author[1]/uri", doc),
45 {:ok, public_key} <- User.get_public_key_for_ap_id(uri),
46 magic_key <- encode_key(public_key) do
51 def decode_and_validate(magickey, salmon) do
52 [data, type, encoding, alg, sig] = decode(salmon)
55 [data, type, encoding, alg]
56 |> Enum.map(&Base.url_encode64/1)
59 key = decode_key(magickey)
61 verify = :public_key.verify(signed_text, :sha256, sig, key)
70 def decode_key("RSA." <> magickey) do
71 make_integer = fn bin ->
72 list = :erlang.binary_to_list(bin)
73 Enum.reduce(list, 0, fn el, acc -> acc <<< 8 ||| el end)
79 |> Enum.map(fn n -> Base.url_decode64!(n, padding: false) end)
80 |> Enum.map(make_integer)
82 {:RSAPublicKey, modulus, exponent}
85 def encode_key({:RSAPublicKey, modulus, exponent}) do
86 modulus_enc = :binary.encode_unsigned(modulus) |> Base.url_encode64()
87 exponent_enc = :binary.encode_unsigned(exponent) |> Base.url_encode64()
89 "RSA.#{modulus_enc}.#{exponent_enc}"
92 def encode(private_key, doc) do
93 type = "application/atom+xml"
94 encoding = "base64url"
98 [doc, type, encoding, alg]
99 |> Enum.map(&Base.url_encode64/1)
104 |> :public_key.sign(:sha256, private_key)
106 |> Base.url_encode64()
110 |> Base.url_encode64()
112 # Don't need proper xml building, these strings are safe to leave unescaped
114 <?xml version="1.0" encoding="UTF-8"?>
115 <me:env xmlns:me="http://salmon-protocol.org/ns/magic-env">
116 <me:data type="application/atom+xml">#{doc_base64}</me:data>
117 <me:encoding>#{encoding}</me:encoding>
118 <me:alg>#{alg}</me:alg>
119 <me:sig>#{signature}</me:sig>
126 def remote_users(%{data: %{"to" => to} = data}) do
127 to = to ++ (data["cc"] || [])
130 |> Enum.map(fn id -> User.get_cached_by_ap_id(id) end)
131 |> Enum.filter(fn user -> user && !user.local end)
134 @doc "Pushes an activity to remote account."
135 def publish_one(%{recipient: %{info: %{salmon: salmon}}} = params),
136 do: publish_one(Map.put(params, :recipient, salmon))
138 def publish_one(%{recipient: url, feed: feed} = params) when is_binary(url) do
139 with {:ok, %{status: code}} when code in 200..299 <-
143 [{"Content-Type", "application/magic-envelope+xml"}]
145 if !Map.has_key?(params, :unreachable_since) || params[:unreachable_since],
146 do: Instances.set_reachable(url)
148 Logger.debug(fn -> "Pushed to #{url}, code #{code}" end)
152 unless params[:unreachable_since], do: Instances.set_reachable(url)
153 Logger.debug(fn -> "Pushing Salmon to #{url} failed, #{inspect(e)}" end)
154 {:error, "Unreachable instance"}
158 def publish_one(_), do: :noop
160 @supported_activities [
169 def is_representable?(%Activity{data: %{"type" => type}} = activity)
170 when type in @supported_activities,
171 do: Visibility.is_public?(activity)
173 def is_representable?(_), do: false
176 Publishes an activity to remote accounts
178 @spec publish(User.t(), Pleroma.Activity.t()) :: none
179 def publish(user, activity)
181 def publish(%{info: %{keys: keys}} = user, %{data: %{"type" => type}} = activity)
182 when type in @supported_activities do
183 feed = ActivityRepresenter.to_simple_form(activity, user, true)
187 ActivityRepresenter.wrap_with_entry(feed)
188 |> :xmerl.export_simple(:xmerl_xml)
191 {:ok, private, _} = Keys.keys_from_pem(keys)
192 {:ok, feed} = encode(private, feed)
194 remote_users = remote_users(activity)
196 salmon_urls = Enum.map(remote_users, & &1.info.salmon)
197 reachable_urls_metadata = Instances.filter_reachable(salmon_urls)
198 reachable_urls = Map.keys(reachable_urls_metadata)
201 |> Enum.filter(&(&1.info.salmon in reachable_urls))
202 |> Enum.each(fn remote_user ->
203 Logger.debug(fn -> "Sending Salmon to #{remote_user.ap_id}" end)
205 Publisher.enqueue_one(__MODULE__, %{
206 recipient: remote_user,
208 unreachable_since: reachable_urls_metadata[remote_user.info.salmon]
214 def publish(%{id: id}, _), do: Logger.debug(fn -> "Keys missing for user #{id}" end)
216 def gather_webfinger_links(%User{} = user) do
217 {:ok, _private, public} = Keys.keys_from_pem(user.info.keys)
218 magic_key = encode_key(public)
221 %{"rel" => "salmon", "href" => OStatus.salmon_path(user)},
223 "rel" => "magic-public-key",
224 "href" => "data:application/magic-public-key,#{magic_key}"
229 def gather_nodeinfo_protocol_names, do: []