entropy estimation, but causes an immediate reseed after the input
(read in sizeof(u_int64_t) chunks) is "harvested".
This will be used in the reboot "reseeder", coming in another
commit. This can be used very effectively at any time you think
your randomness is compromised; something like
# (ps -gauxwww; netstat -an; dmesg; vmstat -c10 1) > /dev/random
will give the attacker something to think about.
with splhigh(). However, the entropy-harvesting routine needs pretty
serious irq-protection, as it is called out of irq handlers etc.
Clues given by: bde
structure; remind myself in the cooments. Also regroup all the Yarrow
variables at the top of the variable list; they are "special".
(no functional change).
stack. It's bad for your machine's health.
Make the two huge structs in reseed() static to prevent crashes. This
is the bug that people have been running into and panic()ing on for the
past few days.
Reviewed by: phk
This is work-in-progress, and the entropy-gathering routines are not
yet present. As such, this should be viewed as a pretty reasonable
PRNG with _ABSOLUTELY_NO_ security!!
Entropy gathering will be the subject of ongoing work.
This is written as a module, and as such is unloadable, but there is
no refcounting done. I would like to use something like device_busy(9)
to achieve this (eventually).
Lots of useful ideas from: bde, phk, Jeroen van Gelderen
Reviewed by: dfr
