2015-06-17 16:40 GMT+08:00 Reindl Harald <h.rei...@thelounge.net>: > > Am 17.06.2015 um 05:06 schrieb cee1: >> >> 2015-06-16 0:21 GMT+08:00 Lennart Poettering <lenn...@poettering.net>: >>> >>> On Mon, 15.06.15 23:33, cee1 (fykc...@gmail.com) wrote: >>>> >>>> Hi, >>>> >>>> I maybe got confused. >>>> >>>> First, systemd-random-seed.service will save a "seed" from >>>> /dev/urandom when shutdown, and load that "seed" to /dev/urandom when >>>> next boot up. >>>> >>>> My questions are: >>>> 1. Can we not save a seed, but load a seed that is read from ** >>>> /dev/random ** to ** /dev/urandom **? >>> >>> >>> The seed is used for both. Then you'd feed the stuff you got from the >>> RNG back into the RNG which is a pointless excercise. >> >> >> systemd-random-seed.service will load the "seed on disk" to >> /dev/urandom, and save a "seed" to disk when shutdown, right? >> >> The article at http://www.2uo.de/myths-about-urandom/ suggests us >> saving the seed as soon as there is enough entropy(means read from >> /dev/random? if returns, there's enough entropy), > > > well, so you read the seed and inject it to /dev/random followed by read > /dev/random and overwrite the seed for the next boot - don't sounds that > good
What I means is: 1. Load a saved seed to /dev/urandom. 2. The service read /dev/random, which will block until kernel thinks there's enough entropy - then the Random Number should be good? 3. Save the random number returned in step 2 on disk. -- Regards, - cee1 _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
