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* random(9): bump removal to FreeBSD 16.0Ed Maste2025-05-111-2/+2
| | | | | | | It has not yet been removed, and still has some in-tree consumers. PR: 277655 Sponsored by: The FreeBSD Foundation
* random(9): bump removal to FreeBSD 15.0Ed Maste2024-03-181-2/+2
| | | | | | | It has not yet been removed, and still has some in-tree consumers. PR: 277655 Sponsored by: The FreeBSD Foundation
* Remove $FreeBSD$: two-line nroff patternWarner Losh2023-08-161-2/+0
| | | | Remove /^\.\\"\n\.\\"\s*\$FreeBSD\$$\n/
* random(9): Restore historical [0,2^31-1] output range and related manLawrence Stewart2021-03-241-11/+14
| | | | | | | | | | | | | | | | | | | | | | | | documention. Commit SVN r364219 / Git 8a0edc914ffd changed random(9) to be a shim around prng32(9) and inadvertently caused random(9) to begin returning numbers in the range [0,2^32-1] instead of [0,2^31-1], where the latter has been the documented range for decades. The increased output range has been identified as the source of numerous bugs in code written against the historical output range e.g. ipfw "prob" rules and stats(3) are known to be affected, and a non-exhaustive audit of the tree identified other random(9) consumers which are also likely affected. As random(9) is deprecated and slated for eventual removal in 14.0, consumers should gradually be audited and migrated to prng(9). Submitted by: Loic Prylli <lprylli@netflix.com> Obtained from: Netflix Reviewed by: cem, delphij, imp MFC after: 1 day MFC to: stable/13, releng/13.0 Differential Revision: https://reviews.freebsd.org/D29385
* random(9): Deprecate random(9), remove meaningless srandom(9)Conrad Meyer2019-12-261-36/+11
| | | | | | | | | | | | | | | | | | | | | | | | srandom(9) is meaningless on SMP systems or any system with, say, interrupts. One could never rely on random(9) to produce a reproducible sequence of outputs on the basis of a specific srandom() seed because the global state was shared by all kernel contexts. As such, removing it is literally indistinguishable to random(9) consumers (as compared with retaining it). Mark random(9) as deprecated and slated for quick removal. This is not to say we intend to remove all fast, non-cryptographic PRNG(s) in the kernel. It/they just won't be random(9), as it exists today, in either name or implementation. Before random(9) is removed, a replacement will be provided and in-tree consumers will be converted. Note that despite the name, the random(9) interface does not bear any resemblance to random(3). Instead, it is the same crummy 1988 Park-Miller LCG used in libc rand(3). Notes: svn path=/head/; revision=356097
* Revert r346410 and r346411Conrad Meyer2019-04-191-12/+1
| | | | | | | | libkern in .PATH has too many filename conflicts with libc and my -DNO_CLEAN tinderbox didn't catch that ahead of time. Mea culpa. Notes: svn path=/head/; revision=346420
* libkern: Bring in arc4random_uniform(9) from libcConrad Meyer2019-04-191-1/+12
| | | | | | | | | | | | | | | | It is a useful arc4random wrapper in the kernel for much the same reasons as in userspace. Move the source to libkern (because kernel build is restricted to sys/, but userspace can include any file it likes) and build kernel and libc versions from the same source file. Copy the documentation from arc4random_uniform(3) to the section 9 page. While here, add missing arc4random_buf(9) symlink. Sponsored by: Dell EMC Isilon Notes: svn path=/head/; revision=346410
* random(4): Add is_random_seeded(9) KPIConrad Meyer2019-04-161-1/+11
| | | | | | | | | | | | | | | The imagined use is for early boot consumers of random to be able to make decisions based on whether random is available yet or not. One such consumer seems to be __stack_chk_init(), which runs immediately after random is initialized. A follow-up patch will attempt to address that. Reported by: many Reviewed by: delphij (except man page) Approved by: secteam(delphij) Differential Revision: https://reviews.freebsd.org/D19926 Notes: svn path=/head/; revision=346282
* random(4): Block read_random(9) on initial seedingConrad Meyer2019-04-151-96/+101
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | read_random() is/was used, mostly without error checking, in a lot of very sensitive places in the kernel -- including seeding the widely used arc4random(9). Most uses, especially arc4random(9), should block until the device is seeded rather than proceeding with a bogus or empty seed. I did not spy any obvious kernel consumers where blocking would be inappropriate (in the sense that lack of entropy would be ok -- I did not investigate locking angle thoroughly). In many instances, arc4random_buf(9) or that family of APIs would be more appropriate anyway; that work was done in r345865. A minor cleanup was made to the implementation of the READ_RANDOM function: instead of using a variable-length array on the stack to temporarily store all full random blocks sufficient to satisfy the requested 'len', only store a single block on the stack. This has some benefit in terms of reducing stack usage, reducing memcpy overhead and reducing devrandom output leakage via the stack. Additionally, the stack block is now safely zeroed if it was used. One caveat of this change is that the kern.arandom sysctl no longer returns zero bytes immediately if the random device is not seeded. This means that FreeBSD-specific userspace applications which attempted to handle an unseeded random device may be broken by this change. If such behavior is needed, it can be replaced by the more portable getrandom(2) GRND_NONBLOCK option. On any typical FreeBSD system, entropy is persisted on read/write media and used to seed the random device very early in boot, and blocking is never a problem. This change primarily impacts the behavior of /dev/random on embedded systems with read-only media that do not configure "nodevice random". We toggle the default from 'charge on blindly with no entropy' to 'block indefinitely.' This default is safer, but may cause frustration. Embedded system designers using FreeBSD have several options. The most obvious is to plan to have a small writable NVRAM or NAND to persist entropy, like larger systems. Early entropy can be fed from any loader, or by writing directly to /dev/random during boot. Some embedded SoCs now provide a fast hardware entropy source; this would also work for quickly seeding Fortuna. A 3rd option would be creating an embedded-specific, more simplistic random module, like that designed by DJB in [1] (this design still requires a small rewritable media for forward secrecy). Finally, the least preferred option might be "nodevice random", although I plan to remove this in a subsequent revision. To help developers emulate the behavior of these embedded systems on ordinary workstations, the tunable kern.random.block_seeded_status was added. When set to 1, it blocks the random device. I attempted to document this change in random.4 and random.9 and ran into a bunch of out-of-date or irrelevant or inaccurate content and ended up rototilling those documents more than I intended to. Sorry. I think they're in a better state now. PR: 230875 Reviewed by: delphij, markm (earlier version) Approved by: secteam(delphij), devrandom(markm) Relnotes: yes Differential Revision: https://reviews.freebsd.org/D19744 Notes: svn path=/head/; revision=346250
* Fix a small typo: "the the".Ed Schouten2015-07-161-2/+2
| | | | | | | Spotted by: wblock Notes: svn path=/head/; revision=285637
* Implement the CloudABI random_get() system call.Ed Schouten2015-07-141-3/+38
| | | | | | | | | | | | | | | | | The random_get() system call works similar to getentropy()/getrandom() on OpenBSD/Linux. It fills a buffer with random data. This change introduces a new function, read_random_uio(), that is used to implement read() on the random devices. We can call into this function from within the CloudABI compatibility layer. Approved by: secteam Reviewed by: jmg, markm, wblock Obtained from: https://github.com/NuxiNL/freebsd Differential Revision: https://reviews.freebsd.org/D3053 Notes: svn path=/head/; revision=285549
* Updated random(4) boot/shutdown scripting.Mark Murray2015-06-301-2/+0
| | | | | | | | | | Fix the man pages as well. Differential Revision: https://reviews.freebsd.org/D2924 Approved by: so (delphij) Notes: svn path=/head/; revision=284960
* Huge cleanup of random(4) code.Mark Murray2015-06-301-27/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * GENERAL - Update copyright. - Make kernel options for RANDOM_YARROW and RANDOM_DUMMY. Set neither to ON, which means we want Fortuna - If there is no 'device random' in the kernel, there will be NO random(4) device in the kernel, and the KERN_ARND sysctl will return nothing. With RANDOM_DUMMY there will be a random(4) that always blocks. - Repair kern.arandom (KERN_ARND sysctl). The old version went through arc4random(9) and was a bit weird. - Adjust arc4random stirring a bit - the existing code looks a little suspect. - Fix the nasty pre- and post-read overloading by providing explictit functions to do these tasks. - Redo read_random(9) so as to duplicate random(4)'s read internals. This makes it a first-class citizen rather than a hack. - Move stuff out of locked regions when it does not need to be there. - Trim RANDOM_DEBUG printfs. Some are excess to requirement, some behind boot verbose. - Use SYSINIT to sequence the startup. - Fix init/deinit sysctl stuff. - Make relevant sysctls also tunables. - Add different harvesting "styles" to allow for different requirements (direct, queue, fast). - Add harvesting of FFS atime events. This needs to be checked for weighing down the FS code. - Add harvesting of slab allocator events. This needs to be checked for weighing down the allocator code. - Fix the random(9) manpage. - Loadable modules are not present for now. These will be re-engineered when the dust settles. - Use macros for locks. - Fix comments. * src/share/man/... - Update the man pages. * src/etc/... - The startup/shutdown work is done in D2924. * src/UPDATING - Add UPDATING announcement. * src/sys/dev/random/build.sh - Add copyright. - Add libz for unit tests. * src/sys/dev/random/dummy.c - Remove; no longer needed. Functionality incorporated into randomdev.*. * live_entropy_sources.c live_entropy_sources.h - Remove; content moved. - move content to randomdev.[ch] and optimise. * src/sys/dev/random/random_adaptors.c src/sys/dev/random/random_adaptors.h - Remove; plugability is no longer used. Compile-time algorithm selection is the way to go. * src/sys/dev/random/random_harvestq.c src/sys/dev/random/random_harvestq.h - Add early (re)boot-time randomness caching. * src/sys/dev/random/randomdev_soft.c src/sys/dev/random/randomdev_soft.h - Remove; no longer needed. * src/sys/dev/random/uint128.h - Provide a fake uint128_t; if a real one ever arrived, we can use that instead. All that is needed here is N=0, N++, N==0, and some localised trickery is used to manufacture a 128-bit 0ULLL. * src/sys/dev/random/unit_test.c src/sys/dev/random/unit_test.h - Improve unit tests; previously the testing human needed clairvoyance; now the test will do a basic check of compressibility. Clairvoyant talent is still a good idea. - This is still a long way off a proper unit test. * src/sys/dev/random/fortuna.c src/sys/dev/random/fortuna.h - Improve messy union to just uint128_t. - Remove unneeded 'static struct fortuna_start_cache'. - Tighten up up arithmetic. - Provide a method to allow eternal junk to be introduced; harden it against blatant by compress/hashing. - Assert that locks are held correctly. - Fix the nasty pre- and post-read overloading by providing explictit functions to do these tasks. - Turn into self-sufficient module (no longer requires randomdev_soft.[ch]) * src/sys/dev/random/yarrow.c src/sys/dev/random/yarrow.h - Improve messy union to just uint128_t. - Remove unneeded 'staic struct start_cache'. - Tighten up up arithmetic. - Provide a method to allow eternal junk to be introduced; harden it against blatant by compress/hashing. - Assert that locks are held correctly. - Fix the nasty pre- and post-read overloading by providing explictit functions to do these tasks. - Turn into self-sufficient module (no longer requires randomdev_soft.[ch]) - Fix some magic numbers elsewhere used as FAST and SLOW. Differential Revision: https://reviews.freebsd.org/D2025 Reviewed by: vsevolod,delphij,rwatson,trasz,jmg Approved by: so (delphij) Notes: svn path=/head/; revision=284959
* Globally replace u_int*_t from (non-contributed) man pages.Ed Schouten2012-02-121-1/+1
| | | | | | | | | | | | | | The reasoning behind this, is that if we are consistent in our documentation about the uint*_t stuff, people will be less tempted to write new code that uses the non-standard types. I am not going to bump the man page dates, as these changes can be considered style nits. The meaning of the man pages is unaffected. MFC after: 1 month Notes: svn path=/head/; revision=231564
* mdoc: order prologue macros consistently by Dd/Dt/OsUlrich Spörlein2010-04-141-1/+1
| | | | | | | | | | | Although groff_mdoc(7) gives another impression, this is the ordering most widely used and also required by mdocml/mandoc. Reviewed by: ru Approved by: philip, ed (mentors) Notes: svn path=/head/; revision=206622
* Mechanically kill hard sentence breaks and double whitespaces.Ruslan Ermilov2004-07-031-2/+4
| | | | Notes: svn path=/head/; revision=131530
* Mdoc Janitor:Hiten Pandya2003-10-231-1/+2
| | | | | | | * Fix hard sentence breaks. Notes: svn path=/head/; revision=121385
* mdoc(7) police: scheduled sweep.Ruslan Ermilov2002-11-291-9/+10
| | | | | | | Approved by: re Notes: svn path=/head/; revision=107383
* Slight overhaul of arc4random() and friends.Poul-Henning Kamp2002-10-111-6/+24
| | | | | | | | | | | | | | | | | | | | | | One bug fixed: Use getmicrouptime() to trigger reseeds so that we cannot be tricked by a clock being stepped backwards. Express parameters in natural units and with natural names. Don't use struct timeval more than we need to. Various stylistic and readability polishing. Introduce arc4rand(void *ptr, u_int len, int reseed) function which returns a stream of pseudo-random bytes, observing the automatic reseed criteria as well as allowing forced reseeds. Rewrite arc4random() in terms of arc4rand(). Sponsored by: DARPA & NAI Labs. Notes: svn path=/head/; revision=104900
* Update the prototype for read_random to reflect that the count parameterChad David2002-04-121-2/+2
| | | | | | | | is an int not an unsigned int, and that it returns an int not an unsigned int. Notes: svn path=/head/; revision=94482
* mdoc(7) police: Use the new .In macro for #include statements.Ruslan Ermilov2001-10-011-2/+2
| | | | Notes: svn path=/head/; revision=84306
* mdoc(7) police: remove extraneous .Pp before and/or after .Sh.Dima Dorfman2001-07-091-1/+0
| | | | Notes: svn path=/head/; revision=79454
* mdoc(7) police: normalize .Nd.Ruslan Ermilov2001-04-181-1/+1
| | | | Notes: svn path=/head/; revision=75670
* Sort NAMES section and separate Nm arguments from trailing punctuation.Sheldon Hearn2000-11-131-6/+6
| | | | Notes: svn path=/head/; revision=68678
* Add a man page for part of the PRNG API.Mark Murray2000-10-141-0/+135
Notes: svn path=/head/; revision=67115