libdecaf

%% -*- mode: erlang; tab-width: 4; indent-tabs-mode: 1; st-rulers: [70] -*-
%% vim: ts=4 sw=4 ft=erlang noet
%%%-------------------------------------------------------------------
%%% @author Andrew Bennett <potatosaladx@gmail.com>
%%% @copyright 2015-2022, Andrew Bennett
%%% @doc
%%%
%%% @end
%%% Created :  29 Feb 2016 by Andrew Bennett <potatosaladx@gmail.com>
%%%-------------------------------------------------------------------
-module(libdecaf_sha2).

%% API
-export([
	hash/2,
	hash/3,
	init/1,
	update/2,
	final/1,
	final/2
]).

%% Macros
-define(WRAP_STATE(T, R),
	case R of
		NewState when is_reference(NewState) ->
			{T, NewState};
		Other ->
			Other
	end).
-define(SHA2_512_OUTPUT_BYTES, 64).

%%%===================================================================
%%% API functions
%%%===================================================================

hash(sha2_512, In) ->
	libdecaf:sha2_512(In, ?SHA2_512_OUTPUT_BYTES);
hash(Type, In) ->
	erlang:error({badarg, [Type, In]}).

hash(sha2_512, In, Outlen) ->
	libdecaf:sha2_512(In, Outlen);
hash(Type, In, Outlen) ->
	erlang:error({badarg, [Type, In, Outlen]}).

init(sha2_512) ->
	?WRAP_STATE(sha2_512, libdecaf:sha2_512_init());
init(Type) ->
	erlang:error({badarg, [Type]}).

update({sha2_512, State}, In) ->
	?WRAP_STATE(sha2_512, libdecaf:sha2_512_update(State, In));
update(State, In) ->
	erlang:error({badarg, [State, In]}).

final({sha2_512, State}) ->
	libdecaf:sha2_512_final(State, ?SHA2_512_OUTPUT_BYTES);
final(State) ->
	erlang:error({badarg, [State]}).

final({sha2_512, State}, Outlen) ->
	libdecaf:sha2_512_final(State, Outlen);
final(State, Outlen) ->
	erlang:error({badarg, [State, Outlen]}).

%%%-------------------------------------------------------------------
%%% Internal functions
%%%-------------------------------------------------------------------