+++ /dev/null
-// 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);
-}
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