(Please keep all CCs). On Sun, 01 Aug 2010, Jerry Leichter wrote: > file might be reused: Stir in the date and time and anything else > that might vary - even if it's readily guessable/detectable - along
Well, yes, we have several *guessable* sources of variable data available during early userspace that we could use. We can also distill them through sha256. But it would add very little variation across reboots of the same box, and that variation is easily guessable. Worse, the entire contents of the base data is also guessable, *and* almost all of it is available after boot (and that does include the date/time). It would be something like this: ( dmesg | sha256 ; ( date -u ; date +%N ) | sha256) | dd of=/dev/urandom In addition to the usual shuffling done using the seed file. However, someone would have to put forth a good, solid technical explanation of why the above would give a measurable increase on the security of a system where the seed file does not exist (or is being reused due to a failure that caused an early reboot). As I said, the entire data used (dmesg, system time) is available and/or guessable to very high precision after boot [when a seed file has not been refreshed], AND the variation between boots can be rather small *and* that variation is also guessable. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh _______________________________________________ Pkg-sysvinit-devel mailing list [email protected] http://lists.alioth.debian.org/mailman/listinfo/pkg-sysvinit-devel
