From 3946a5529132c80793a9e5ee665a3cd6b0835310 Mon Sep 17 00:00:00 2001 From: Etienne CHAMPETIER Date: Mon, 27 Jun 2016 15:53:30 +0000 Subject: base-files: seed /dev/urandom This commit: 1) seed /dev/urandom with the saved seeds as early as possible (see /lib/preinit/81_urandom_seed) 2) save a seed at /etc/urandom.seed if it doesn't exists 3) save a new seed each boot at "system.@system[0].urandom_seed" (see /etc/init.d/urandom_seed) We use getrandom() so we are sure /dev/urandom pool is initialized Seed size is 512 bytes (ie /proc/sys/kernel/random/poolsize / 8) it's the same size as in ubuntu 14.04 and all systemd systems Seeding /dev/urandom doesn't change entropy estimation, so we still have "random: ubus urandom read with 4 bits of entropy available" messages in the logs, but we can now ignore them if after "urandom-seed: Seeding with ..." message Saving a new seed on each boot is disabled by default to avoid too much writes without user consent v2: log preinit messages to /dev/kmsg v3: use non generic function name for logging, as /lib/preinit/ files are all sourced together in /etc/preinit v4: after a lot of discussion on the ML, use a uci config param v5: config param is now the path of the seed Signed-off-by: Etienne CHAMPETIER Acked-by: Jo-Philipp Wich --- package/base-files/files/bin/config_generate | 1 + 1 file changed, 1 insertion(+) (limited to 'package/base-files/files/bin') diff --git a/package/base-files/files/bin/config_generate b/package/base-files/files/bin/config_generate index 22cc1571aa..7f34eec881 100755 --- a/package/base-files/files/bin/config_generate +++ b/package/base-files/files/bin/config_generate @@ -230,6 +230,7 @@ generate_static_system() { set system.@system[-1].timezone='UTC' set system.@system[-1].ttylogin='0' set system.@system[-1].log_size='64' + set system.@system[-1].urandom_seed='0' delete system.ntp set system.ntp='timeserver' -- cgit v1.2.3