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* This is the much-discussed major upgrade to the random(4) device, known to ↵Mark Murray2014-10-301-141/+0
| | | | | | | | | | | | | | | | | | | | | | you all as /dev/random. This code has had an extensive rewrite and a good series of reviews, both by the author and other parties. This means a lot of code has been simplified. Pluggable structures for high-rate entropy generators are available, and it is most definitely not the case that /dev/random can be driven by only a hardware souce any more. This has been designed out of the device. Hardware sources are stirred into the CSPRNG (Yarrow, Fortuna) like any other entropy source. Pluggable modules may be written by third parties for additional sources. The harvesting structures and consequently the locking have been simplified. Entropy harvesting is done in a more general way (the documentation for this will follow). There is some GREAT entropy to be had in the UMA allocator, but it is disabled for now as messing with that is likely to annoy many people. The venerable (but effective) Yarrow algorithm, which is no longer supported by its authors now has an alternative, Fortuna. For now, Yarrow is retained as the default algorithm, but this may be changed using a kernel option. It is intended to make Fortuna the default algorithm for 11.0. Interested parties are encouraged to read ISBN 978-0-470-47424-2 "Cryptography Engineering" By Ferguson, Schneier and Kohno for Fortuna's gory details. Heck, read it anyway. Many thanks to Arthur Mesh who did early grunt work, and who got caught in the crossfire rather more than he deserved to. My thanks also to folks who helped me thresh this out on whiteboards and in the odd "Hallway track", or otherwise. My Nomex pants are on. Let the feedback commence! Reviewed by: trasz,des(partial),imp(partial?),rwatson(partial?) Approved by: so(des) Notes: svn path=/head/; revision=273872
* Convert the random entropy harvesting code to use a const void * pointerAdrian Chadd2013-11-011-1/+1
| | | | | | | | | | | | | | rather than just void *. Then, as part of this, convert a couple of mbuf m->m_data accesses to mtod(m, const void *). Reviewed by: markm Approved by: security-officer (delphij) Sponsored by: Netflix, Inc. Notes: svn path=/head/; revision=257525
* Snapshot. This passes the build test, but has not yet been finished or debugged.Mark Murray2013-10-041-7/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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) Notes: svn path=/projects/random_number_generator/; revision=256042
* Snapshot of current work;Mark Murray2013-08-261-3/+3
| | | | | | | | | | | | | | | | | | 1) Clean up namespace; only use "Yarrow" where it is Yarrow-specific or close enough to the Yarrow algorithm. For the rest use a neutral name. 2) Tidy up headers; put private stuff in private places. More could be done here. 3) Streamline the hashing/encryption; no need for a 256-bit counter; 128 bits will last for long enough. There are bits of debug code lying around; these will be removed at a later stage. Notes: svn path=/projects/random_number_generator/; revision=254927
* Generate a warning if the kernel's arc4random() is seeded with bogus entropy.David Schultz2012-01-161-0/+8
| | | | Notes: svn path=/head/; revision=230230
* Rename the kthread_xxx (e.g. kthread_create()) callsJulian Elischer2007-10-201-2/+2
| | | | | | | | | | | | | | to kproc_xxx as they actually make whole processes. Thos makes way for us to add REAL kthread_create() and friends that actually make theads. it turns out that most of these calls actually end up being moved back to the thread version when it's added. but we need to make this cosmetic change first. I'd LOVE to do this rename in 7.0 so that we can eventually MFC the new kthread_xxx() calls. Notes: svn path=/head/; revision=172836
* Annotate that get_cyclecount() can be expensive on some platforms,Robert Watson2004-10-181-0/+4
| | | | | | | | which juxtaposes nicely with the comment just above on how the harvest function must be cheap. Notes: svn path=/head/; revision=136672
* Default to harvesting everything. This is to help give a fasterMark Murray2004-04-161-1/+1
| | | | | | | | startup. harvesting can be turned OFF in etc/rc.d/* if it is a burden. Notes: svn path=/head/; revision=128320
* Reorganise the entropy device so that high-yield entropy sourcesMark Murray2004-04-091-14/+12
| | | | | | | | | | can more easily be used INSTEAD OF the hard-working Yarrow. The only hardware source used at this point is the one inside the VIA C3 Nehemiah (Stepping 3 and above) CPU. More sources will be added in due course. Contributions welcome! Notes: svn path=/head/; revision=128059
* kthread_exit() no longer requires Giant, so don't force callers to acquireJohn Baldwin2004-03-051-1/+0
| | | | | | | | | Giant just to call kthread_exit(). Requested by: many Notes: svn path=/head/; revision=126674
* Overhaul the entropy device:Mark Murray2003-11-171-5/+5
| | | | | | | | | | | | | | | | | | | | | 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. Notes: svn path=/head/; revision=122871
* Use __FBSDID().David E. O'Brien2003-08-241-1/+3
| | | | | | | Also some minor style cleanups. Notes: svn path=/head/; revision=119418
* Remove srandom():Andrey A. Chernov2003-02-051-6/+1
| | | | | | | | | | | 1) It is already called in init_main.c:proc0_post() 2) It is called each time read_random_phony() called, because "initialized" variable is never set to 1. Approved by: markm Notes: svn path=/head/; revision=110404
* Fix really dumb braino of mine; cast a sizeof() to an int, which it isMark Murray2002-04-211-1/+1
| | | | | | | being compared to, not size_t, which it already is. Notes: svn path=/head/; revision=95197
* Massive lint-inspired cleanup.Mark Murray2002-03-031-10/+12
| | | | | | | | | | Remove unneeded includes. Deal with unused function arguments. Resolve a boatload of signed/unsigned imcompatabilities. Etc. Notes: svn path=/head/; revision=91600
* Fix type warnings.Mark Murray2001-07-201-4/+8
| | | | | | | PR: 29101 Notes: svn path=/head/; revision=80032
* Catch up to header include changes:John Baldwin2001-03-281-0/+1
| | | | | | | | - <sys/mutex.h> now requires <sys/systm.h> - <sys/mutex.h> and <sys/sx.h> now require <sys/lock.h> Notes: svn path=/head/; revision=74914
* Silence (harmless) warnings.Mark Murray2001-03-241-0/+1
| | | | Notes: svn path=/head/; revision=74741
* Very large makeover of the /dev/random driver.Mark Murray2001-03-101-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Notes: svn path=/head/; revision=74072
* Provide the infrastructure for sysadmins to select the broad classMark Murray2001-02-181-0/+3
| | | | | | | | of entropy harvesting they wish to perform: "ethernet" (LAN), point-to-point and interrupt. Notes: svn path=/head/; revision=72667
* Change and clean the mutex lock interface.Bosko Milekic2001-02-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order) Notes: svn path=/head/; revision=72200
* select() DKI is now in <sys/selinfo.h>.Garrett Wollman2001-01-091-1/+1
| | | | Notes: svn path=/head/; revision=70834
* Stop explicitly using nanotime(9) and use the new get_cyclecounter(9)Mark Murray2000-11-251-16/+11
| | | | | | | | | | | | call instead. This makes a pretty dramatic difference to the amount of work that the harvester needs to do - it is much friendlier on the system. (80386 and 80486 class machines will notice little, as the new get_cyclecounter() call is a wrapper round nanotime(9) for them). Notes: svn path=/head/; revision=69168
* Catch up to moving headers:John Baldwin2000-10-201-1/+1
| | | | | | | | - machine/ipl.h -> sys/ipl.h - machine/mutex.h -> sys/mutex.h Notes: svn path=/head/; revision=67365
* After some complaints about the dir names, the random device isMark Murray2000-10-141-17/+60
| | | | | | | | | | | | | | | | | | | | | | | 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. Notes: svn path=/head/; revision=67112
* Remove unneeded includes.Mark Murray2000-09-211-3/+0
| | | | | | | Submitted by: phk Notes: svn path=/head/; revision=66155
* Large upgrade to the entropy device; mainly inspired by feedbackMark Murray2000-09-101-0/+19
| | | | | | | | | | | | | | | | | | | 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. Notes: svn path=/head/; revision=65686
* o Fix a horrible bug where small reads (< 8 bytes) would return theMark Murray2000-07-251-4/+4
| | | | | | | | | | | 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") Notes: svn path=/head/; revision=63855
* Clean this up with some BDE-inspired fixes.Mark Murray2000-07-231-10/+12
| | | | | | | | | | | | | | o Make the comments KNF-compliant. o Use nanotime instead of getnanotime; the manpage lies about the kern.timecounter.method - it has been removed. o Fix the ENTROPYSOURCE const permanently. o Make variable names more consistent. o Make function prototypes more consistent. Some more needs to be done; to follow. Notes: svn path=/head/; revision=63771
* Storing to a pointer is (effectively) atomic; no need to protect thisMark Murray2000-07-111-8/+0
| | | | | | | | | | 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 Notes: svn path=/head/; revision=62969
* Add entropy gathering code. This will work whether the module isMark Murray2000-07-071-0/+81
compiled in or loaded. Notes: svn path=/head/; revision=62765