mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
174 lines
4.8 KiB
C
174 lines
4.8 KiB
C
![]() |
// SPDX-License-Identifier: BSD-3-Clause
|
||
|
/* $OpenBSD: siphash.c,v 1.3 2015/02/20 11:51:03 tedu Exp $ */
|
||
|
|
||
|
/*-
|
||
|
* Copyright (c) 2013 Andre Oppermann <andre@FreeBSD.org>
|
||
|
* All rights reserved.
|
||
|
*
|
||
|
* Redistribution and use in source and binary forms, with or without
|
||
|
* modification, are permitted provided that the following conditions
|
||
|
* are met:
|
||
|
* 1. Redistributions of source code must retain the above copyright
|
||
|
* notice, this list of conditions and the following disclaimer.
|
||
|
* 2. Redistributions in binary form must reproduce the above copyright
|
||
|
* notice, this list of conditions and the following disclaimer in the
|
||
|
* documentation and/or other materials provided with the distribution.
|
||
|
* 3. The name of the author may not be used to endorse or promote
|
||
|
* products derived from this software without specific prior written
|
||
|
* permission.
|
||
|
*
|
||
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||
|
* SUCH DAMAGE.
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* SipHash is a family of PRFs SipHash-c-d where the integer parameters c and d
|
||
|
* are the number of compression rounds and the number of finalization rounds.
|
||
|
* A compression round is identical to a finalization round and this round
|
||
|
* function is called SipRound. Given a 128-bit key k and a (possibly empty)
|
||
|
* byte string m, SipHash-c-d returns a 64-bit value SipHash-c-d(k; m).
|
||
|
*
|
||
|
* Implemented from the paper "SipHash: a fast short-input PRF", 2012.09.18,
|
||
|
* by Jean-Philippe Aumasson and Daniel J. Bernstein,
|
||
|
* Permanent Document ID b9a943a805fbfc6fde808af9fc0ecdfa
|
||
|
* https://131002.net/siphash/siphash.pdf
|
||
|
* https://131002.net/siphash/
|
||
|
*/
|
||
|
|
||
|
#include <asm/byteorder.h>
|
||
|
#include <asm/unaligned.h>
|
||
|
#include <linux/bitops.h>
|
||
|
#include <linux/string.h>
|
||
|
|
||
|
#include "siphash.h"
|
||
|
|
||
|
static void SipHash_Rounds(SIPHASH_CTX *ctx, int rounds)
|
||
|
{
|
||
|
while (rounds--) {
|
||
|
ctx->v[0] += ctx->v[1];
|
||
|
ctx->v[2] += ctx->v[3];
|
||
|
ctx->v[1] = rol64(ctx->v[1], 13);
|
||
|
ctx->v[3] = rol64(ctx->v[3], 16);
|
||
|
|
||
|
ctx->v[1] ^= ctx->v[0];
|
||
|
ctx->v[3] ^= ctx->v[2];
|
||
|
ctx->v[0] = rol64(ctx->v[0], 32);
|
||
|
|
||
|
ctx->v[2] += ctx->v[1];
|
||
|
ctx->v[0] += ctx->v[3];
|
||
|
ctx->v[1] = rol64(ctx->v[1], 17);
|
||
|
ctx->v[3] = rol64(ctx->v[3], 21);
|
||
|
|
||
|
ctx->v[1] ^= ctx->v[2];
|
||
|
ctx->v[3] ^= ctx->v[0];
|
||
|
ctx->v[2] = rol64(ctx->v[2], 32);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static void SipHash_CRounds(SIPHASH_CTX *ctx, const void *ptr, int rounds)
|
||
|
{
|
||
|
u64 m = get_unaligned_le64(ptr);
|
||
|
|
||
|
ctx->v[3] ^= m;
|
||
|
SipHash_Rounds(ctx, rounds);
|
||
|
ctx->v[0] ^= m;
|
||
|
}
|
||
|
|
||
|
void SipHash_Init(SIPHASH_CTX *ctx, const SIPHASH_KEY *key)
|
||
|
{
|
||
|
u64 k0, k1;
|
||
|
|
||
|
k0 = le64_to_cpu(key->k0);
|
||
|
k1 = le64_to_cpu(key->k1);
|
||
|
|
||
|
ctx->v[0] = 0x736f6d6570736575ULL ^ k0;
|
||
|
ctx->v[1] = 0x646f72616e646f6dULL ^ k1;
|
||
|
ctx->v[2] = 0x6c7967656e657261ULL ^ k0;
|
||
|
ctx->v[3] = 0x7465646279746573ULL ^ k1;
|
||
|
|
||
|
memset(ctx->buf, 0, sizeof(ctx->buf));
|
||
|
ctx->bytes = 0;
|
||
|
}
|
||
|
|
||
|
void SipHash_Update(SIPHASH_CTX *ctx, int rc, int rf,
|
||
|
const void *src, size_t len)
|
||
|
{
|
||
|
const u8 *ptr = src;
|
||
|
size_t left, used;
|
||
|
|
||
|
if (len == 0)
|
||
|
return;
|
||
|
|
||
|
used = ctx->bytes % sizeof(ctx->buf);
|
||
|
ctx->bytes += len;
|
||
|
|
||
|
if (used > 0) {
|
||
|
left = sizeof(ctx->buf) - used;
|
||
|
|
||
|
if (len >= left) {
|
||
|
memcpy(&ctx->buf[used], ptr, left);
|
||
|
SipHash_CRounds(ctx, ctx->buf, rc);
|
||
|
len -= left;
|
||
|
ptr += left;
|
||
|
} else {
|
||
|
memcpy(&ctx->buf[used], ptr, len);
|
||
|
return;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
while (len >= sizeof(ctx->buf)) {
|
||
|
SipHash_CRounds(ctx, ptr, rc);
|
||
|
len -= sizeof(ctx->buf);
|
||
|
ptr += sizeof(ctx->buf);
|
||
|
}
|
||
|
|
||
|
if (len > 0)
|
||
|
memcpy(&ctx->buf[used], ptr, len);
|
||
|
}
|
||
|
|
||
|
void SipHash_Final(void *dst, SIPHASH_CTX *ctx, int rc, int rf)
|
||
|
{
|
||
|
u64 r;
|
||
|
|
||
|
r = SipHash_End(ctx, rc, rf);
|
||
|
|
||
|
*((__le64 *) dst) = cpu_to_le64(r);
|
||
|
}
|
||
|
|
||
|
u64 SipHash_End(SIPHASH_CTX *ctx, int rc, int rf)
|
||
|
{
|
||
|
u64 r;
|
||
|
size_t left, used;
|
||
|
|
||
|
used = ctx->bytes % sizeof(ctx->buf);
|
||
|
left = sizeof(ctx->buf) - used;
|
||
|
memset(&ctx->buf[used], 0, left - 1);
|
||
|
ctx->buf[7] = ctx->bytes;
|
||
|
|
||
|
SipHash_CRounds(ctx, ctx->buf, rc);
|
||
|
ctx->v[2] ^= 0xff;
|
||
|
SipHash_Rounds(ctx, rf);
|
||
|
|
||
|
r = (ctx->v[0] ^ ctx->v[1]) ^ (ctx->v[2] ^ ctx->v[3]);
|
||
|
memset(ctx, 0, sizeof(*ctx));
|
||
|
return (r);
|
||
|
}
|
||
|
|
||
|
u64 SipHash(const SIPHASH_KEY *key, int rc, int rf, const void *src, size_t len)
|
||
|
{
|
||
|
SIPHASH_CTX ctx;
|
||
|
|
||
|
SipHash_Init(&ctx, key);
|
||
|
SipHash_Update(&ctx, rc, rf, src, len);
|
||
|
return SipHash_End(&ctx, rc, rf);
|
||
|
}
|