1 /* $OpenBSD: siphash.h,v 1.5 2015/02/20 11:51:03 tedu Exp $ */ 2 /*- 3 * Copyright (c) 2013 Andre Oppermann <andre@FreeBSD.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote 15 * products derived from this software without specific prior written 16 * permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * $FreeBSD$ 31 */ 32 33 /* 34 * SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions) 35 * optimized for speed on short messages returning a 64bit hash/digest value. 36 * 37 * The number of rounds is defined during the initialization: 38 * SipHash24_Init() for the fast and resonable strong version 39 * SipHash48_Init() for the strong version (half as fast) 40 * 41 * struct SIPHASH_CTX ctx; 42 * SipHash24_Init(&ctx); 43 * SipHash_SetKey(&ctx, "16bytes long key"); 44 * SipHash_Update(&ctx, pointer_to_string, length_of_string); 45 * SipHash_Final(output, &ctx); 46 */ 47 48 #ifndef _SIPHASH_H_ 49 #define _SIPHASH_H_ 50 51 #define SIPHASH_BLOCK_LENGTH 8 52 #define SIPHASH_KEY_LENGTH 16 53 #define SIPHASH_DIGEST_LENGTH 8 54 55 typedef struct _SIPHASH_CTX { 56 uint64_t v[4]; 57 uint8_t buf[SIPHASH_BLOCK_LENGTH]; 58 uint32_t bytes; 59 } SIPHASH_CTX; 60 61 typedef struct { 62 uint64_t k0; 63 uint64_t k1; 64 } SIPHASH_KEY; 65 66 void SipHash_Init(SIPHASH_CTX *, const SIPHASH_KEY *); 67 void SipHash_Update(SIPHASH_CTX *, int, int, const void *, size_t) 68 __bounded((__buffer__, 4, 5)); 69 uint64_t SipHash_End(SIPHASH_CTX *, int, int); 70 void SipHash_Final(void *, SIPHASH_CTX *, int, int) 71 __bounded((__minbytes__, 1, SIPHASH_DIGEST_LENGTH)); 72 uint64_t SipHash(const SIPHASH_KEY *, int, int, const void *, size_t) 73 __bounded((__buffer__, 4, 5)); 74 75 #define SipHash24_Init(_c, _k) SipHash_Init((_c), (_k)) 76 #define SipHash24_Update(_c, _p, _l) SipHash_Update((_c), 2, 4, (_p), (_l)) 77 #define SipHash24_End(_d) SipHash_End((_d), 2, 4) 78 #define SipHash24_Final(_d, _c) SipHash_Final((_d), (_c), 2, 4) 79 #define SipHash24(_k, _p, _l) SipHash((_k), 2, 4, (_p), (_l)) 80 81 #define SipHash48_Init(_c, _k) SipHash_Init((_c), (_k)) 82 #define SipHash48_Update(_c, _p, _l) SipHash_Update((_c), 4, 8, (_p), (_l)) 83 #define SipHash48_End(_d) SipHash_End((_d), 4, 8) 84 #define SipHash48_Final(_d, _c) SipHash_Final((_d), (_c), 4, 8) 85 #define SipHash48(_k, _p, _l) SipHash((_k), 4, 8, (_p), (_l)) 86 87 #endif /* _SIPHASH_H_ */ 88