From fce6747f55fd538917f2bd60e601dc95866c16d0 Mon Sep 17 00:00:00 2001 From: markm Date: Thu, 30 Oct 2014 21:21:53 +0000 Subject: This is the much-discussed major upgrade to the random(4) device, known to you all as /dev/random. This code has had an extensive rewrite and a good series of reviews, both by the author and other parties. This means a lot of code has been simplified. Pluggable structures for high-rate entropy generators are available, and it is most definitely not the case that /dev/random can be driven by only a hardware souce any more. This has been designed out of the device. Hardware sources are stirred into the CSPRNG (Yarrow, Fortuna) like any other entropy source. Pluggable modules may be written by third parties for additional sources. The harvesting structures and consequently the locking have been simplified. Entropy harvesting is done in a more general way (the documentation for this will follow). There is some GREAT entropy to be had in the UMA allocator, but it is disabled for now as messing with that is likely to annoy many people. The venerable (but effective) Yarrow algorithm, which is no longer supported by its authors now has an alternative, Fortuna. For now, Yarrow is retained as the default algorithm, but this may be changed using a kernel option. It is intended to make Fortuna the default algorithm for 11.0. Interested parties are encouraged to read ISBN 978-0-470-47424-2 "Cryptography Engineering" By Ferguson, Schneier and Kohno for Fortuna's gory details. Heck, read it anyway. Many thanks to Arthur Mesh who did early grunt work, and who got caught in the crossfire rather more than he deserved to. My thanks also to folks who helped me thresh this out on whiteboards and in the odd "Hallway track", or otherwise. My Nomex pants are on. Let the feedback commence! Reviewed by: trasz,des(partial),imp(partial?),rwatson(partial?) Approved by: so(des) --- etc/defaults/rc.conf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'etc/defaults') diff --git a/etc/defaults/rc.conf b/etc/defaults/rc.conf index 18989fa..79799bf 100644 --- a/etc/defaults/rc.conf +++ b/etc/defaults/rc.conf @@ -645,7 +645,7 @@ update_motd="YES" # update version info in /etc/motd (or NO) entropy_file="/entropy" # Set to NO to disable caching entropy through reboots. # /var/db/entropy-file is preferred if / is not avail. entropy_dir="/var/db/entropy" # Set to NO to disable caching entropy via cron. -entropy_save_sz="2048" # Size of the entropy cache files. +entropy_save_sz="4096" # Size of the entropy cache files. entropy_save_num="8" # Number of entropy cache files to save. harvest_interrupt="YES" # Entropy device harvests interrupt randomness harvest_ethernet="YES" # Entropy device harvests ethernet randomness -- cgit v1.1