File

util/random.lua @ 11432:113f3912c7cb

util: Add Teal interface definition files Enables writing code in Teal that is aware of the interfaces and function prototypes in these other utils. Could also be used to do type checks on Lua sources, but this tends to have a lot of noise.
author Kim Alvefur <zash@zash.se>
date Tue, 09 Mar 2021 14:36:46 +0100
parent 10016:af8c514e5cf7
child 12446:e54b8a5e35ad
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-- Prosody IM
-- Copyright (C) 2008-2014 Matthew Wild
-- Copyright (C) 2008-2014 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local ok, crand = pcall(require, "util.crand");
if ok then return crand; end

local urandom, urandom_err = io.open("/dev/urandom", "r");

local function bytes(n)
	local data, err = urandom:read(n);
	if not data then
		if err then
			error("Unable to retrieve data from secure random number generator (/dev/urandom): "..tostring(err));
		else
			error("Secure random number generator (/dev/urandom) returned an end-of-file condition");
		end
	end
	return data;
end

if not urandom then
	function bytes()
		error("Unable to obtain a secure random number generator, please see https://prosody.im/doc/random ("..urandom_err..")");
	end
end

return {
	bytes = bytes;
	_source = "/dev/urandom";
};