happen in interrupt context; 1) sleep locks, and 2) malloc/free
calls.
1) is fixed by using spin locks instead.
2) is fixed by preallocating a FIFO (implemented with a STAILQ)
and using elements from this FIFO instead. This turns out
to be rather fast.
OK'ed by: re (scottl)
Thanks to: peter, jhb, rwatson, jake
Apologies to: *
o Each source gets its own queue, which is a FIFO, not a ring buffer.
The FIFOs are implemented with the sys/queue.h macros. The separation
is so that a low entropy/high rate source can't swamp the harvester
with low-grade entropy and destroy the reseeds.
o Each FIFO is limited to 256 (set as a macro, so adjustable) events
queueable. Full FIFOs are ignored by the harvester. This is to
prevent memory wastage, and helps to keep the kernel thread CPU
usage within reasonable limits.
o There is no need to break up the event harvesting into ${burst}
sized chunks, so retire that feature.
o Break the device away from its roots with the memory device, and
allow it to get its major number automagically.
thread being waken up. The thread waken up can run at a priority as
high as after tsleep().
- Replace selwakeup()s with selwakeuppri()s and pass appropriate
priorities.
- Add cv_broadcastpri() which raises the priority of the broadcast
threads. Used by selwakeuppri() if collision occurs.
Not objected in: -arch, -current
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
doesn't give them enough stack to do much before blowing away the pcb.
This adds MI and MD code to allow the allocation of an alternate kstack
who's size can be speficied when calling kthread_create. Passing the
value 0 prevents the alternate kstack from being created. Note that the
ia64 MD code is missing for now, and PowerPC was only partially written
due to the pmap.c being incomplete there.
Though this patch does not modify anything to make use of the alternate
kstack, acpi and usb are good candidates.
Reviewed by: jake, peter, jhb
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
o Separate the kernel stuff from the Yarrow algorithm. Yarrow is now
well contained in one source file and one header.
o Replace the Blowfish-based crypto routines with Rijndael-based ones.
(Rijndael is the new AES algorithm). The huge improvement in
Rijndael's key-agility over Blowfish means that this is an
extremely dramatic improvement in speed, and makes a heck of
a difference in its (lack of) CPU load.
o Clean up the sysctl's. At BDE's prompting, I have gone back to
static sysctls.
o Bug fixes. The streamlining of the crypto stuff enabled me to
find and fix some bugs. DES also found a bug in the reseed routine
which is fixed.
o Change the way reseeds clear "used" entropy. Previously, only the
source(s) that caused a reseed were cleared. Now all sources in the
relevant pool(s) are cleared.
o Code tidy-up. Mostly to make it (nearly) 80-column compliant.
exactly the same functionality via a sysctl, making this feature
a run-time option.
The default is 1(ON), which means that /dev/random device will
NOT block at startup.
setting kern.random.sys.seeded to 0(OFF) will cause /dev/random
to block until the next reseed, at which stage the sysctl
will be changed back to 1(ON).
While I'm here, clean up the sysctls, and make them dynamic.
Reviewed by: des
Tested on Alpha by: obrien
<sys/proc.h> to <sys/systm.h>.
Correctly document the #includes needed in the manpage.
Add one now needed #include of <sys/systm.h>.
Remove the consequent 48 unused #includes of <sys/proc.h>.
priority "0" and without PCATCH, so it was uninterruptable. And
even when it did wake up after entropy arrived, it exited after the
wakeup without actually reading the freshly arrived entropy. I
sent this to Mark before but it seems he is in transit.
Mark: feel free to replace this if it gets in your way.
now in dirs called sys/*/random/ instead of sys/*/randomdev/*.
Introduce blocking, but only at startup; the random device will
block until the first reseed happens to prevent clients from
using untrustworthy output.
Provide a read_random() call for the rest of the kernel so that
the entropy device does not need to be present. This means that
things like IPX no longer need to have "device random" hardcoded
into thir kernel config. The downside is that read_random() will
provide very poor output until the entropy device is loaded and
reseeded. It is recommended that developers do NOT use the
read_random() call; instead, they should use arc4random() which
internally uses read_random().
Clean up the mutex and locking code a bit; this makes it possible
to unload the module again.
hangover from previous experimentation. Remove it. This will clean
up gratuitous needs for forward references and other namespace
pollution.
Moaned about by: bde
Brought to my attention by: bp
from many folk.
o The reseed process is now a kthread. With SMPng, kthreads are
pre-emptive, so the annoying jerkiness of the mouse is gone.
o The data structures are protected by mutexes now, not splfoo()/splx().
o The cryptographic routines are broken out into their own subroutines.
this facilitates review, and possible replacement if that is ever
found necessary.
Thanks to: kris, green, peter, jasone, grog, jhb
Forgotten to thank: You know who you are; no offense intended.
wrong bytes.
o Improve the public interface; use void* instead of char* or u_int64_t
to pass arbitrary data around.
Submitted by: kris ("horrible bug")
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.
device with Yarrow, and although I coded for that in dev/MAKEDEV, I forgot
to _tell_ folks.
This commit adds back the /dev/urandom device (as a duplicate) of /dev/random,
until such time as it can be properly announced.
This will help the openssl users quite a lot.
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
