Commit Graph

163 Commits

Author SHA1 Message Date
pfg
4736ccfd9c sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
cem
6c629a609f aesni(4): CRYPTO_AES_NIST_GCM_16 mandates MAC
Remove some dead conditionals and add an assertion around behavior already
present in aesni_process().

Silence a few Coverity false positives.

CIDs:		1381571, 1381557
Sponsored by:	Dell EMC Isilon
2017-10-04 21:15:45 +00:00
cem
ff255b872c aesni(4): Fix GCC build
The GCC xmmintrin.h header brokenly includes mm_malloc.h unconditionally.
(The Clang version of xmmintrin.h only includes mm_malloc.h if not compiling
in standalone mode.)

Hack around GCC's broken header by defining the include guard macro ahead of
including xmmintrin.h.

Reported by:	lwhsu, jhb
Tested by:	lwhsu
Sponsored by:	Dell EMC Isilon
2017-09-29 19:56:09 +00:00
cem
de7a7877e1 aesni(4): Add support for x86 SHA intrinsics
Some x86 class CPUs have accelerated intrinsics for SHA1 and SHA256.
Provide this functionality on CPUs that support it.

This implements CRYPTO_SHA1, CRYPTO_SHA1_HMAC, and CRYPTO_SHA2_256_HMAC.

Correctness: The cryptotest.py suite in tests/sys/opencrypto has been
enhanced to verify SHA1 and SHA256 HMAC using standard NIST test vectors.
The test passes on this driver.  Additionally, jhb's cryptocheck tool has
been used to compare various random inputs against OpenSSL.  This test also
passes.

Rough performance averages on AMD Ryzen 1950X (4kB buffer):
aesni:      SHA1: ~8300 Mb/s    SHA256: ~8000 Mb/s
cryptosoft:       ~1800 Mb/s    SHA256: ~1800 Mb/s

So ~4.4-4.6x speedup depending on algorithm choice.  This is consistent with
the results the Linux folks saw for 4kB buffers.

The driver borrows SHA update code from sys/crypto sha1 and sha256.  The
intrinsic step function comes from Intel under a 3-clause BSDL.[0]  The
intel_sha_extensions_sha<foo>_intrinsic.c files were renamed and lightly
modified (added const, resolved a warning or two; included the sha_sse
header to declare the functions).

[0]: https://software.intel.com/en-us/articles/intel-sha-extensions-implementations

Reviewed by:	jhb
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D12452
2017-09-26 23:12:32 +00:00
cem
14d71cb7ed opencrypto: Use C99 initializers for auth_hash instances
A misordering in the Via padlock driver really strongly suggested that these
should use C99 named initializers.

No functional change.

Sponsored by:	Dell EMC Isilon
2017-09-26 17:52:52 +00:00
cem
0c65f5254f opencrypto: Loosen restriction on HMAC key sizes
Theoretically, HMACs do not actually have any limit on key sizes.
Transforms should compact input keys larger than the HMAC block size by
using the transform (hash) on the input key.

(Short input keys are padded out with zeros to the HMAC block size.)

Still, not all FreeBSD crypto drivers that provide HMAC functionality
handle longer-than-blocksize keys appropriately, so enforce a "maximum" key
length in the crypto API for auth_hashes that previously expressed a
requirement.  (The "maximum" is the size of a single HMAC block for the
given transform.)  Unconstrained auth_hashes are left as-is.

I believe the previous hardcoded sizes were committed in the original
import of opencrypto from OpenBSD and are due to specific protocol
details of IPSec.  Note that none of the previous sizes actually matched
the appropriate HMAC block size.

The previous hardcoded sizes made the SHA tests in cryptotest.py
useless for testing FreeBSD crypto drivers; none of the NIST-KAT example
inputs had keys sized to the previous expectations.

The following drivers were audited to check that they handled keys up to
the block size of the HMAC safely:

  Software HMAC:
    * padlock(4)
    * cesa
    * glxsb
    * safe(4)
    * ubsec(4)

  Hardware accelerated HMAC:
    * ccr(4)
    * hifn(4)
    * sec(4) (Only supports up to 64 byte keys despite claiming to
      support SHA2 HMACs, but validates input key sizes)
    * cryptocteon (MIPS)
    * nlmsec (MIPS)
    * rmisec (MIPS) (Amusingly, does not appear to use key material at
      all -- presumed broken)

Reviewed by:	jhb (previous version), rlibby (previous version)
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D12437
2017-09-26 16:18:10 +00:00
cem
3d7d2e7188 aesni(4): Fix another trivial typo (aensi -> aesni)
Sponsored by:	Dell EMC Isilon
2017-09-20 18:31:36 +00:00
cem
4596057f43 aesni(4): Fix trivial typo (AQUIRE -> ACQUIRE)
Sponsored by:	Dell EMC Isilon
2017-09-20 17:53:25 +00:00
rlibby
520a2a0be9 aesni: quiet -Wcast-qual
Reviewed by:	delphij
Approved by:	markj (mentor)
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D12021
2017-08-16 22:54:35 +00:00
emaste
1901c3e1f2 Remove register keyword from sys/ and ANSIfy prototypes
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.

ANSIfy related prototypes while here.

Reviewed by:	cem, jhb
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D10193
2017-05-17 00:34:34 +00:00
des
4a175969bb Fix counter increment in Salsa and ChaCha.
In my eagerness to eliminate a branch which is taken once per 2^38
bytes of keystream, I forgot that the state words are in host order.
Thus, the counter increment code worked fine on little-endian
machines, but not on big-endian ones.  Switch to a simpler (branchful)
solution.
2017-04-22 01:06:23 +00:00
markm
bd86cc8ebf Replace the RC4 algorithm for generating in-kernel secure random
numbers with Chacha20. Keep the API, though, as that is what the
other *BSD's have done.

Use the boot-time entropy stash (if present) to bootstrap the
in-kernel entropy source.

Reviewed by: delphij,rwatson
Approved by: so(delphij)
MFC after: 2 months
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D10048
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2017-04-16 09:11:02 +00:00
des
992ce5e20c 3BSD-licensed implementation of the chacha20 stream cipher, intended for
use by the upcoming arc4random replacement.
2017-04-15 20:51:53 +00:00
allanjude
6a205a3252 Implement boot-time encryption key passing (keybuf)
This patch adds a general mechanism for providing encryption keys to the
kernel from the boot loader. This is intended to enable GELI support at
boot time, providing a better mechanism for passing keys to the kernel
than environment variables. It is designed to be extensible to other
applications, and can easily handle multiple encrypted volumes with
different keys.

This mechanism is currently used by the pending GELI EFI work.
Additionally, this mechanism can potentially be used to interface with
GRUB, opening up options for coreboot+GRUB configurations with completely
encrypted disks.

Another benefit over the existing system is that it does not require
re-deriving the user key from the password at each boot stage.

Most of this patch was written by Eric McCorkle. It was extended by
Allan Jude with a number of minor enhancements and extending the keybuf
feature into boot2.

GELI user keys are now derived once, in boot2, then passed to the loader,
which reuses the key, then passes it to the kernel, where the GELI module
destroys the keybuf after decrypting the volumes.

Submitted by:	Eric McCorkle <eric@metricspace.net> (Original Version)
Reviewed by:	oshogbo (earlier version), cem (earlier version)
MFC after:	3 weeks
Relnotes:	yes
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D9575
2017-04-01 05:05:22 +00:00
nyan
259480b6de Remove pc98 support completely.
I thank all developers and contributors for pc98.

Relnotes:	yes
2017-01-28 02:22:15 +00:00
emaste
d69e3c3b7e libmd: add noexec stack annotation in skein_block_asm.s
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2017-01-07 19:26:25 +00:00
andrew
97bbe2fb33 Add accelerated AES with using the ARMv8 crypto instructions. This is based
on the AES-NI code, and modified as needed for use on ARMv8. When loaded
the driver will check the appropriate field in the id_aa64isar0_el1
register to see if AES is supported, and if so the probe function will
signal the driver should attach.

With this I have seen up to 2000Mb/s from the cryptotest test with a single
thread on a ThunderX Pass 2.0.

Reviewed by:	imp
Obtained from:	ABT Systems Ltd
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D8297
2016-11-21 11:18:00 +00:00
asomers
1bd8919011 Fix C++ includability of crypto headers with static array sizes
C99 allows array function parameters to use the static keyword for their
sizes. This tells the compiler that the parameter will have at least the
specified size, and calling code will fail to compile if that guarantee is
not met. However, this syntax is not legal in C++.

This commit reverts r300824, which worked around the problem for
sys/sys/md5.h only, and introduces a new macro: min_size(). min_size(x) can
be used in headers as a static array size, but will still compile in C++
mode.

Reviewed by:	cem, ed
MFC after:	4 weeks
Sponsored by:	Spectra Logic Corp
Differential Revision:	https://reviews.freebsd.org/D8277
2016-10-18 23:20:49 +00:00
emaste
b76d29a58e libmd: introduce functions that operate on an fd instead of filename
Reviewed by:	allanjude, cem
MFC after:	2 months
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D8264
2016-10-17 13:47:22 +00:00
allanjude
86e28072cd Fix typo in skein amd64 assembly
Sponsored by:	ScaleEngine Inc.
2016-09-08 02:38:55 +00:00
allanjude
8cebbf47be Connect the SHA-512t256 and Skein hashing algorithms to ZFS
Support for the new hashing algorithms in ZFS was introduced in r289422
However it was disconnected because FreeBSD lacked implementations of
SHA-512 (truncated to 256 bits), and Skein.

These implementations were introduced in r300921 and r300966 respectively

This commit connects them to ZFS and enabled these new checksum algorithms

This new algorithms are not supported by the boot blocks, so do not use them
on your root dataset if you boot from ZFS.

Relnotes:	yes
Sponsored by:	ScaleEngine Inc.
2016-05-31 04:12:14 +00:00
cperciva
b67598a549 Retune SHA2 code for improved performance on CPUs with more ILP and
a preference for memory load instructions over large code footprints
with embedded immediate variables.

On amd64 CPUs from 2007-2008 there is not a significant change, but
amd64 CPUs from 2009-2010 get roughly 10% more throughput with this
code; amd64 CPUs from 2011-2012 get roughly 15% more throughput; and
AMD64 CPUs from 2013-2015 get 20-25% more throughput.  The Raspberry
Pi 2 increases its throughput by 6-8%.

Sponsored by:	Tarsnap Backup Inc.
Performance tested by:	allanjude
MFC after:	3 weeks
2016-05-29 17:26:40 +00:00
allanjude
6d6e6f6722 Import the skein hashing algorithm, based on the threefish block cipher
Connect it to userland (libmd, libcrypt, sbin/md5) and kernel (crypto.ko)

Support for skein as a ZFS checksum algorithm was introduced in r289422
but is disconnected because FreeBSD lacked a Skein implementation.

A further commit will enable it in ZFS.

Reviewed by:	cem
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D6166
2016-05-29 01:15:36 +00:00
allanjude
4581e38971 Implement SHA-512 truncated (224 and 256 bits)
This implements SHA-512/256, which generates a 256 bit hash by
calculating the SHA-512 then truncating the result. A different initial
value is used, making the result different from the first 256 bits of
the SHA-512 of the same input. SHA-512 is ~50% faster than SHA-256 on
64bit platforms, so the result is a faster 256 bit hash.

The main goal of this implementation is to enable support for this
faster hashing algorithm in ZFS. The feature was introduced into ZFS
in r289422, but is disconnected because SHA-512/256 support was missing.
A further commit will enable it in ZFS.

This is the follow on to r292782

Reviewed by:	cem
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D6061
2016-05-28 16:06:07 +00:00
cem
444253bba5 crypto routines: Hint minimum buffer sizes to the compiler
Use the C99 'static' keyword to hint to the compiler IVs and output digest
sizes.  The keyword informs the compiler of the minimum valid size for a given
array.  Obviously not every pointer can be validated (i.e., the compiler can
produce false negative but not false positive reports).

No functional change.  No ABI change.

Sponsored by:	EMC / Isilon Storage Division
2016-05-26 19:29:29 +00:00
cem
2d92a3cb28 aesni(4): Initialize error before use
Reported by:	Coverity
CID:		1331554
Sponsored by:	EMC / Isilon Storage Division
2016-04-20 03:05:32 +00:00
allanjude
2502999acd Break up opencrypto/xform.c so it can be reused piecemeal
Keep xform.c as a meta-file including the broken out bits
existing code that includes xform.c continues to work as normal

Individual algorithms can now be reused elsewhere, including outside
of the kernel

Reviewed by:	bapt (previous version), gnn, delphij
Approved by:	secteam
MFC after:	1 week
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D4674
2015-12-30 22:43:07 +00:00
allanjude
c7c2f2dfab Replace sys/crypto/sha2/sha2.c with lib/libmd/sha512c.c
cperciva's libmd implementation is 5-30% faster

The same was done for SHA256 previously in r263218

cperciva's implementation was lacking SHA-384 which I implemented, validated against OpenSSL and the NIST documentation

Extend sbin/md5 to create sha384(1)

Chase dependancies on sys/crypto/sha2/sha2.{c,h} and replace them with sha512{c.c,.h}

Reviewed by:	cperciva, des, delphij
Approved by:	secteam, bapt (mentor)
MFC after:	2 weeks
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D3929
2015-12-27 17:33:59 +00:00
jmg
584181912d const'ify an arg that we don't update... 2015-07-29 23:37:15 +00:00
jmg
ec1fe94d10 Complete the move that was started w/ r263218.. For some reason I
didn't delete the files, so that means we need to bring the changes in
r282726 to the correct files..

make tinderbox completed with this patch...
2015-07-11 03:12:34 +00:00
jmg
d374814126 upon further examination, it turns out that _unregister_all already
provides the guarantee that no threads will be in the _newsession code..
This is provided by the CRYPTODRIVER lock...  This makes the pause
unneeded...
2015-07-08 22:48:41 +00:00
jmg
1ca19e1938 address an issue where consumers, like IPsec, can reuse the same
session in multiple threads w/o locking..  There was a single fpu
context shared per session, if multiple threads were using the session,
and both migrated away, they could corrupt each other's fpu context...

This patch adds a per cpu context and a lock to protect it...

It also tries to better address unloading of the aesni module...
The pause will be removed once the OpenCrypto Framework provides a
better method for draining callers into _newsession...

I first discovered the fpu context sharing issue w/ a flood ping over
an IPsec tunnel between two bhyve machines...  The patch in D3015
was used to verify that this fix does fix the issue...

Reviewed by:	gnn, kib (both earlier versions)
Differential Revision:        https://reviews.freebsd.org/D3016
2015-07-08 19:15:29 +00:00
jmg
2b00c9ed0d unroll the loop slightly... This improves performance enough to
justify, especially for CBC performance where we can't pipeline..  I
don't happen to have my measurements handy though...

Sponsored by:	Netflix, Inc.
2015-07-07 20:31:09 +00:00
jmg
abd8f81b92 Fix for non-random IV's when CRD_F_IV_PRESENT and CRD_F_IV_EXPLICIT
flags are not specified... This bug was introduced in r275732...

This only affects IPsec ESP only policies w/ the aesni module loaded,
other subsystems specify one or both of the flags...

Reviewed by:	gnn, delphij, eri
2015-07-06 19:30:29 +00:00
jmg
384ca830a8 remove _NORMAL flag which isn't suppose to be used w/ _alloc_ctx...
Reviewed by:	kib (a while ago)
2015-07-06 19:17:56 +00:00
rodrigc
5e984ef151 In the version of gcc in the FreeBSD tree, this modification was made to
the compiler in svn r242182:

#if STDC_HOSTED
#include <mm_malloc.h>
#endif

A similar change was done to clang in the FreeBSD tree in svn r218893:

However, for external gcc toolchains, this patch is not in the compiler's header
file.

This patch to FreeBSD's aesni code allows compilation with an external
gcc toolchain.

Differential Revision: https://reviews.freebsd.org/D2285
Reviewed by:  jmg, dim
Approved by:  dim
2015-04-16 17:42:52 +00:00
jmg
c3ff54cc39 Add some new modes to OpenCrypto. These modes are AES-ICM (can be used
for counter mode), and AES-GCM.  Both of these modes have been added to
the aesni module.

Included is a set of tests to validate that the software and aesni
module calculate the correct values.  These use the NIST KAT test
vectors.  To run the test, you will need to install a soon to be
committed port, nist-kat that will install the vectors.  Using a port
is necessary as the test vectors are around 25MB.

All the man pages were updated.  I have added a new man page, crypto.7,
which includes a description of how to use each mode.  All the new modes
and some other AES modes are present.  It would be good for someone
else to go through and document the other modes.

A new ioctl was added to support AEAD modes which AES-GCM is one of them.
Without this ioctl, it is not possible to test AEAD modes from userland.

Add a timing safe bcmp for use to compare MACs.  Previously we were using
bcmp which could leak timing info and result in the ability to forge
messages.

Add a minor optimization to the aesni module so that single segment
mbufs don't get copied and instead are updated in place.  The aesni
module needs to be updated to support blocked IO so segmented mbufs
don't have to be copied.

We require that the IV be specified for all calls for both GCM and ICM.
This is to ensure proper use of these functions.

Obtained from:	p4: //depot/projects/opencrypto
Relnotes:	yes
Sponsored by:	FreeBSD Foundation
Sponsored by:	NetGate
2014-12-12 19:56:36 +00:00
des
ce96d70e17 Fix gcc build: preserve const qualifier when casting input values.
Noticed by:	bz@
Submitted by:	dim@
2014-11-11 13:37:28 +00:00
des
d656003ded Constify the AES code and propagate to consumers. This allows us to
update the Fortuna code to use SHAd-256 as defined in FS&K.

Approved by:	so (self)
2014-11-10 09:44:38 +00:00
kib
4b355196ab Put the aesni_cipher_setup() and aesni_cipher_process() functions into
the file which is compiled with SSE disabled.  The functions set up
the FPU context for kernel, and compiler optimizations which could
lead to use of XMM registers before the fpu_kern_enter(9) is called or
after fpu_kern_leave(9), panic the machine.

Discussed with:	jmg
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-06-24 06:55:49 +00:00
kib
fe547198b1 Add FPU_KERN_KTHR flag to fpu_kern_enter(9), which avoids saving FPU
context into memory for the kernel threads which called
fpu_kern_thread(9).  This allows the fpu_kern_enter() callers to not
check for is_fpu_kern_thread() to get the optimization.

Apply the flag to padlock(4) and aesni(4).  In aesni_cipher_process(),
do not leak FPU context state on error.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-06-23 07:37:54 +00:00
imp
c39e6fc2c9 NO_MAN= has been deprecated in favor of MAN= for some time, go ahead
and finish the job. ncurses is now the only Makefile in the tree that
uses it since it wasn't a simple mechanical change, and will be
addressed in a future commit.
2014-04-13 05:21:56 +00:00
jmg
eab153cc9d replace the kernel's version w/ cperciva's implementation... In all
my tests, it is faster ~20%, even on an old IXP425 533MHz it is ~45%
faster...  This is partly due to loop unrolling, so the code size does
significantly increase...  I do plan on committing a version that
rolls up the loops again for smaller code size for embedded systems
where size is more important than absolute performance (it'll save ~6k
code)...

The kernel implementation is now shared w/ userland's libcrypt and
libmd...

We drop support for sha256 from sha2.c, so now sha2.c only contains
sha384 and sha512...

Reviewed by:	secteam@
2014-03-16 01:43:23 +00:00
jmg
bf2e9f212d copy these files from lib/libmd in preperation for moving these files
into the kernel...
2014-03-16 00:57:26 +00:00
jmg
f19a97b48c fix broken style(9) in r258399
Pointed out by:	brd
2013-11-23 00:28:18 +00:00
jmg
472b0e6b78 flag that the aesni driver is sync... This means we don't waste a
context switch just to call the done callback...  On my machine, this
improves geli/gzero decrypt performance by ~27% from 550MB/sec to
~700MB/sec...

MFC after:	3 days
2013-11-20 20:25:27 +00:00
jmg
c4e415a9b1 make it so that from/to can be missaligned as it can happen (the geli
regression manages to do it)...  We use a packed struct to coerce
gcc/clang into producing unaligned loads (there is not packed pointer
attribute, otherwise this would be easier)...

use _storeu_ and _loadu_ when using the structure is overkill...

be better at using types properly...  Since we allocate our own key
schedule and make sure it's aligned, use the __m128i type in various
arguments to functions...

clang ignores __aligned on prototypes and gcc errors on them, leave them
in comments to document that these function arguments are require to be
aligned...

about all that changes is movdqa -> movdqu from reading the diff of the
disassembly output...

Noticed by:	symbolics at gmx.com
MFC after:	3 days
2013-11-06 19:14:49 +00:00
jmg
8ec798134a Use the fact that the AES-NI instructions can be pipelined to improve
performance... Use SSE2 instructions for calculating the XTS tweek
factor...  Let the compiler do more work and handle register allocation
by using intrinsics, now only the key schedule is in assembly...

Replace .byte hard coded instructions w/ the proper instructions now
that both clang and gcc support them...

On my machine, pulling the code to userland I saw performance go from
~150MB/sec to 2GB/sec in XTS mode.  GELI on GNOP saw a more modest
increase of about 3x due to other system overhead (geom and
opencrypto)...

These changes allow almost full disk io rate w/ geli...

Reviewed by:	-current, -security
Thanks to:	Mike Hamburg for the XTS tweek algorithm
2013-09-03 18:31:23 +00:00
andre
01fc9682ce Fix const propagation issues to make GCC happy.
Submitted by:	Michael Butler <imb@protected-networks.net>
2013-07-11 16:27:11 +00:00
andre
5c4a796865 SipHash is a cryptographically strong pseudo-random function (a.k.a. keyed
hash function) optimized for speed on short messages returning a 64bit hash/
digest value.

SipHash is simpler and much faster than other secure MACs and competitive
in speed with popular non-cryptographic hash functions.  It uses a 128-bit
key without the hidden cost of a key expansion step.  SipHash iterates a
simple round function consisting of four additions, four xors, and six
rotations, interleaved with xors of message blocks for a pre-defined number
of compression and finalization rounds.  The absence of  secret load/store
addresses or secret branch conditions avoid timing attacks.  No state is
shared between messages.  Hashing is deterministic and doesn't use nonces.
It is not susceptible to length extension attacks.

Target applications include network traffic authentication, message
authentication (MAC) and hash-tables protection against hash-flooding
denial-of-service attacks.

The number of update/finalization rounds is defined during initialization:

 SipHash24_Init() for the fast and reasonable strong version.
 SipHash48_Init() for the strong version (half as fast).

SipHash usage is similar to other hash functions:

 struct SIPHASH_CTX ctx;
 char *k = "16bytes long key"
 char *s = "string";
 uint64_t h = 0;
 SipHash24_Init(&ctx);
 SipHash_SetKey(&ctx, k);
 SipHash_Update(&ctx, s, strlen(s));
 SipHash_Final(&h, &ctx);  /* or */
 h = SipHash_End(&ctx);    /* or */
 h = SipHash24(&ctx, k, s, strlen(s));

It was designed by Jean-Philippe Aumasson and Daniel J. Bernstein and
is described in the paper "SipHash: a fast short-input PRF", 2012.09.18:
 https://131002.net/siphash/siphash.pdf
 Permanent ID: b9a943a805fbfc6fde808af9fc0ecdfa

Implemented by:	andre (based on the paper)
Reviewed by:	cperciva
2013-07-11 14:18:38 +00:00