akkoma/lib/pleroma/mfa/backup_codes.ex

32 lines
990 B
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.MFA.BackupCodes do
@moduledoc """
This module contains functions for generating backup codes.
"""
alias Pleroma.Config
@config_ns [:instance, :multi_factor_authentication, :backup_codes]
@doc """
Generates backup codes.
"""
@spec generate(Keyword.t()) :: list(String.t())
def generate(opts \\ []) do
number_of_codes = Keyword.get(opts, :number_of_codes, default_backup_codes_number())
code_length = Keyword.get(opts, :length, default_backup_codes_code_length())
Enum.map(1..number_of_codes, fn _ ->
:crypto.strong_rand_bytes(div(code_length, 2))
|> Base.encode16(case: :lower)
end)
end
defp default_backup_codes_number, do: Config.get(@config_ns ++ [:number], 5)
defp default_backup_codes_code_length,
do: Config.get(@config_ns ++ [:length], 16)
end