architex/lib/architex_web/federation/sign_request_middleware.ex
2021-09-01 14:43:55 +02:00

41 lines
1.3 KiB
Elixir

defmodule ArchitexWeb.Federation.Middleware.SignRequest do
@behaviour Tesla.Middleware
def call(%Tesla.Env{opts: opts} = env, next, _opts) do
sign = Keyword.get(opts, :sign, true)
case sign_request(env, sign) do
%Tesla.Env{} = env -> Tesla.run(env, next)
:error -> {:error, :sign_request}
end
end
defp sign_request(env, false), do: env
defp sign_request(%Tesla.Env{method: method, url: path, opts: opts, body: body} = env, true) do
origin = Architex.server_name()
object_to_sign = %{
method: Atom.to_string(method) |> String.upcase(),
origin: origin,
uri: URI.decode_www_form(path),
destination: Keyword.fetch!(opts, :server_name)
}
object_to_sign =
if not is_nil(body), do: Map.put(object_to_sign, :content, body), else: object_to_sign
with {:ok, sig, key_id} <- Architex.KeyServer.sign_object(object_to_sign) do
sigs = %{origin => %{key_id => sig}}
auth_headers = create_signature_authorization_headers(sigs, origin)
Tesla.put_headers(env, auth_headers)
end
end
defp create_signature_authorization_headers(signatures, origin) do
Enum.map(signatures[origin], fn {key, sig} ->
{"Authorization", "X-Matrix origin=#{origin},key=\"#{key}\",sig=\"#{sig}\""}
end)
end
end