I replaced the sx_* locks that Arthur used with regular mutexes; this turned out the be the wrong thing to do as the locks need to be sleepable. Revert this folly.
Submitted by: Arthur Mesh <arthurmesh@gmail.com> (In original diff)
Looking pretty good; this mostly works now. New code includes:
* Read cached entropy at startup, both from files and from loader(8) preloaded entropy. Failures are soft, but announced. Untested.
* Use EVENTHANDLER to do above just before we go multiuser. Untested.
been tested. With all sources turned on, this unlocks itself in
a couple of seconds! That is no my box, and there is no guarantee
that this will be the case everywhere.
* Cut debug prints.
* Use the same locks/mutexes all the way through.
* Be a tad more conservative about entropy estimates.
Simplify the malloc pools; We only need one for this device.
Simplify the harvest queue.
Marginally improve the entropy pool hashing, making it a bit faster in the process.
Connect up the hardware "live" source harvesting. This is simplistic for now, and will need to be made rate-adaptive.
All of the above passes a compile test but needs to be debugged.
Contains:
* Refactor the hardware RNG CPU instruction sources to feed into
the software mixer. This is unfinished. The actual harvesting needs
to be sorted out. Modified by me (see below).
* Remove 'frac' parameter from random_harvest(). This was never
used and adds extra code for no good reason.
* Remove device write entropy harvesting. This provided a weak
attack vector, was not very good at bootstrapping the device. To
follow will be a replacement explicit reseed knob.
* Separate out all the RANDOM_PURE sources into separate harvest
entities. This adds some secuity in the case where more than one
is present.
* Review all the code and fix anything obviously messy or inconsistent.
Address som review concerns while I'm here, like rename the pseudo-rng
to 'dummy'.
Submitted by: Arthur Mesh <arthurmesh@gmail.com> (the first item)
