X-Git-Url: https://git.enpas.org/?a=blobdiff_plain;f=util%2Frandom.lua;h=574e2e1cdf384cf7d893530fdcd97c80843aaba7;hb=bca35c227886965fb03723280c0fc79bdadb5faa;hp=5938a94f820ac4e3379c1f56594d3abe07810a15;hpb=41977f3e683e553a2a96b23b467e2ac6b8c3cec3;p=prosody.git

diff --git a/util/random.lua b/util/random.lua
index 5938a94f..574e2e1c 100644
--- a/util/random.lua
+++ b/util/random.lua
@@ -6,35 +6,22 @@
 -- COPYING file in the source package for more information.
 --
 
-local tostring = tostring;
-local os_time = os.time;
-local os_clock = os.clock;
-local ceil = math.ceil;
-local H = require "util.hashes".sha512;
+local ok, crand = pcall(require, "util.crand");
+if ok then return crand; end
 
-local last_uniq_time = 0;
-local function uniq_time()
-	local new_uniq_time = os_time();
-	if last_uniq_time >= new_uniq_time then new_uniq_time = last_uniq_time + 1; end
-	last_uniq_time = new_uniq_time;
-	return new_uniq_time;
-end
+local urandom, urandom_err = io.open("/dev/urandom", "r");
 
-local function new_random(x)
-	return H(x..os_clock()..tostring({}));
+local function seed()
 end
 
-local buffer = new_random(uniq_time());
-
-local function seed(x)
-	buffer = new_random(buffer..x);
+local function bytes(n)
+	return urandom:read(n);
 end
 
-local function bytes(n)
-	if #buffer < n+4 then seed(uniq_time()); end
-	local r = buffer:sub(1, n);
-	buffer = buffer:sub(n+1);
-	return r;
+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 {