I had removed <sys/rnd.h> from files that didn't mention anything of
the rnd(9) API. But they included other files which assumed
<sys/rnd.h> had already been included.
1) Move core entropy-pool code and source/sink/sample management code
to sys/kern from sys/dev.
2) Remove use of NRND as test for presence of entropy-pool code throughout
source tree.
3) Remove use of RND_ENABLED in device drivers as microoptimization to
avoid expensive operations on disabled entropy sources; make the
rnd_add calls do this directly so all callers benefit.
4) Fix bug in recent rnd_add_data()/rnd_add_uint32() changes that might
have lead to slight entropy overestimation for some sources.
5) Add new source types for environmental sensors, power sensors, VM
system events, and skew between clocks, with a sample implementation
for each.
ok releng to go in before the branch due to the difficulty of later
pullup (widespread #ifdef removal and moved files). Tested with release
builds on amd64 and evbarm and live testing on amd64.
<20111022023242.BA26F14A158@mail.netbsd.org>. This change includes
the following:
An initial cleanup and minor reorganization of the entropy pool
code in sys/dev/rnd.c and sys/dev/rndpool.c. Several bugs are
fixed. Some effort is made to accumulate entropy more quickly at
boot time.
A generic interface, "rndsink", is added, for stream generators to
request that they be re-keyed with good quality entropy from the pool
as soon as it is available.
The arc4random()/arc4randbytes() implementation in libkern is
adjusted to use the rndsink interface for rekeying, which helps
address the problem of low-quality keys at boot time.
An implementation of the FIPS 140-2 statistical tests for random
number generator quality is provided (libkern/rngtest.c). This
is based on Greg Rose's implementation from Qualcomm.
A new random stream generator, nist_ctr_drbg, is provided. It is
based on an implementation of the NIST SP800-90 CTR_DRBG by
Henric Jungheim. This generator users AES in a modified counter
mode to generate a backtracking-resistant random stream.
An abstraction layer, "cprng", is provided for in-kernel consumers
of randomness. The arc4random/arc4randbytes API is deprecated for
in-kernel use. It is replaced by "cprng_strong". The current
cprng_fast implementation wraps the existing arc4random
implementation. The current cprng_strong implementation wraps the
new CTR_DRBG implementation. Both interfaces are rekeyed from
the entropy pool automatically at intervals justifiable from best
current cryptographic practice.
In some quick tests, cprng_fast() is about the same speed as
the old arc4randbytes(), and cprng_strong() is about 20% faster
than rnd_extract_data(). Performance is expected to improve.
The AES code in src/crypto/rijndael is no longer an optional
kernel component, as it is required by cprng_strong, which is
not an optional kernel component.
The entropy pool output is subjected to the rngtest tests at
startup time; if it fails, the system will reboot. There is
approximately a 3/10000 chance of a false positive from these
tests. Entropy pool _input_ from hardware random numbers is
subjected to the rngtest tests at attach time, as well as the
FIPS continuous-output test, to detect bad or stuck hardware
RNGs; if any are detected, they are detached, but the system
continues to run.
A problem with rndctl(8) is fixed -- datastructures with
pointers in arrays are no longer passed to userspace (this
was not a security problem, but rather a major issue for
compat32). A new kernel will require a new rndctl.
The sysctl kern.arandom() and kern.urandom() nodes are hooked
up to the new generators, but the /dev/*random pseudodevices
are not, yet.
Manual pages for the new kernel interfaces are forthcoming.
- rather than embedding bufq_state in driver softc,
have a pointer to the former.
- move bufq related functions from kern/subr_disk.c to kern/subr_bufq.c.
- rename method to strategy for consistency.
- move some definitions which don't need to be exposed to the rest of kernel
from sys/bufq.h to sys/bufq_impl.h.
(is it better to move it to kern/ or somewhere?)
- fix some obvious breakage in dev/qbus/ts.c. (not tested)
* simplify and clean the attach code a lot, and support the 'drive'
locator
* pass proper dev_t to readdisklabel() - formerly, the passed value was
completely broken (used incorrect major and wrong minor), but worked
by accident
* worker thread is now spawned per controller, rather than per-drive;
i/o cannot be done concurrently by different drivers, only one
i/o can be pending at any time
* simplify the command queue code, just sleep appropriately when
!poll case, g/c 'async' code formerly needed, move the bio code
from ed_mca.c to edc_mca.c:edc_bio()
* other misc cleanups
and for initial autoconf probes; the latter eliminates need for
deferred configuration (and makes dmesg a bit nicer).
g/c EDF_IODONE flag - protect against interrupt by calling tsleep()
at splbio in worker thread
g/c unneeded stuff, improve some autoconf messages
to be cleared always in edmcadone(), otherwise if there is a write
via bounce buffer followed by read directly to buf, the read operation
would return trashed data (the buf data would get overwritten
by contents of bounce buffer in edmcadone()).
Reset b_resid as necessary when the i/o is done, too.
g/c some unneeded stuff, use lockmgr()-style locking in ed_[un]lock(),
better avoid some deadlocks
These changes make the driver quite a bit more stable. It's actually
reliable enough to be possible to newfs the drive and use it for
read/write filesystem now.
Disk & Controller only at the moment.
This driver still needs some touchup (error recovery is not quite
good, MCA DMA controller goo should be moved to driver independant
location), but is working enough to be usable for others. And I
want this under CVS control :)
Thanks to Scott Telford <st@epcc.ed.ac.uk> for providing me docs for
these devices (IBM DASD Storage Interface Specification for MCA rev. 2.2).
