File

util/random.lua @ 11769:071715a18394

mod_pubsub: Move reversal of item order in <items> Examples in XEP-0060 suggest that items should be listed in chronological order, but we get them from the archive in reverse order. However when requesting specific items by id the results keep that order and we don't want to flip it again. At some point it would likely be best to use the archive API directly instead of this util.cache-compatible wrapper.
author Kim Alvefur <zash@zash.se>
date Sun, 05 Sep 2021 18:42:44 +0200
parent 10016:af8c514e5cf7
child 12446:e54b8a5e35ad
line wrap: on
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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";
};