util/random.lua
author Kim Alvefur <zash@zash.se>
Tue, 14 May 2024 17:07:47 +0200
changeset 13494 6f840763fc73
parent 12979 d10957394a3c
permissions -rw-r--r--
net.server_epoll: Add support for systemd socket activation Allows creating listening sockets and accepting client connections before Prosody starts. This is unlike normal Prosody dynamic resource management, where ports may added and removed at any time, and the ports defined by the config. Weird things happen if these are closed (e.g. due to reload) so here we prevent closing and ensure sockets are reused when opened again.

-- 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, "prosody.util.crand");
if ok and pcall(crand.bytes, 1) 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";
};