akkoma/lib/pleroma/signature.ex
2022-07-18 15:21:27 +01:00

81 lines
2.2 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Signature do
@behaviour HTTPSignatures.Adapter
alias Pleroma.EctoType.ActivityPub.ObjectValidators
alias Pleroma.Keys
alias Pleroma.User
alias Pleroma.Web.ActivityPub.ActivityPub
@known_suffixes ["/publickey", "/main-key"]
def key_id_to_actor_id(key_id) do
uri =
key_id
|> URI.parse()
|> Map.put(:fragment, nil)
|> remove_suffix(@known_suffixes)
maybe_ap_id = URI.to_string(uri)
case ObjectValidators.ObjectID.cast(maybe_ap_id) do
{:ok, ap_id} ->
{:ok, ap_id}
_ ->
case Pleroma.Web.WebFinger.finger(maybe_ap_id) do
%{"ap_id" => ap_id} -> {:ok, ap_id}
_ -> {:error, maybe_ap_id}
end
end
end
defp remove_suffix(uri, [test | rest]) do
if not is_nil(uri.path) and String.ends_with?(uri.path, test) do
Map.put(uri, :path, String.replace(uri.path, test, ""))
else
remove_suffix(uri, rest)
end
end
defp remove_suffix(uri, []), do: uri
def fetch_public_key(conn) do
with %{"keyId" => kid} <- HTTPSignatures.signature_for_conn(conn),
{:ok, actor_id} <- key_id_to_actor_id(kid),
{:ok, public_key} <- User.get_public_key_for_ap_id(actor_id) do
{:ok, public_key}
else
e ->
{:error, e}
end
end
def refetch_public_key(conn) do
with %{"keyId" => kid} <- HTTPSignatures.signature_for_conn(conn),
{:ok, actor_id} <- key_id_to_actor_id(kid),
{:ok, _user} <- ActivityPub.make_user_from_ap_id(actor_id),
{:ok, public_key} <- User.get_public_key_for_ap_id(actor_id) do
{:ok, public_key}
else
e ->
{:error, e}
end
end
def sign(%User{} = user, headers) do
with {:ok, %{keys: keys}} <- User.ensure_keys_present(user),
{:ok, private_key, _} <- Keys.keys_from_pem(keys) do
HTTPSignatures.sign(private_key, user.ap_id <> "#main-key", headers)
end
end
def signed_date, do: signed_date(NaiveDateTime.utc_now())
def signed_date(%NaiveDateTime{} = date) do
Timex.format!(date, "{WDshort}, {0D} {Mshort} {YYYY} {h24}:{m}:{s} GMT")
end
end