1 /*- 2 * Copyright (c) 2013 Andre Oppermann <andre@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote 14 * products derived from this software without specific prior written 15 * permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions) 34 * optimized for speed on short messages returning a 64bit hash/digest value. 35 * 36 * The number of rounds is defined during the initialization: 37 * SipHash24_Init() for the fast and resonable strong version 38 * SipHash48_Init() for the strong version (half as fast) 39 * 40 * struct SIPHASH_CTX ctx; 41 * SipHash24_Init(&ctx); 42 * SipHash_SetKey(&ctx, "16bytes long key"); 43 * SipHash_Update(&ctx, pointer_to_string, length_of_string); 44 * SipHash_Final(output, &ctx); 45 */ 46 47 #ifndef _SIPHASH_H_ 48 #define _SIPHASH_H_ 49 50 #define SIPHASH_BLOCK_LENGTH 8 51 #define SIPHASH_KEY_LENGTH 16 52 #define SIPHASH_DIGEST_LENGTH 8 53 54 typedef struct _SIPHASH_CTX { 55 uint64_t v[4]; 56 union { 57 uint64_t b64; 58 uint8_t b8[8]; 59 } buf; 60 uint64_t bytes; 61 uint8_t buflen; 62 uint8_t rounds_compr; 63 uint8_t rounds_final; 64 uint8_t initialized; 65 } SIPHASH_CTX; 66 67 68 #define SipHash24_Init(x) SipHash_InitX((x), 2, 4) 69 #define SipHash48_Init(x) SipHash_InitX((x), 4, 8) 70 void SipHash_InitX(SIPHASH_CTX *, int, int); 71 void SipHash_SetKey(SIPHASH_CTX *, const uint8_t[static SIPHASH_KEY_LENGTH]); 72 void SipHash_Update(SIPHASH_CTX *, const void *, size_t); 73 void SipHash_Final(uint8_t[static SIPHASH_DIGEST_LENGTH], SIPHASH_CTX *); 74 uint64_t SipHash_End(SIPHASH_CTX *); 75 76 #define SipHash24(x, y, z, i) SipHashX((x), 2, 4, (y), (z), (i)); 77 #define SipHash48(x, y, z, i) SipHashX((x), 4, 8, (y), (z), (i)); 78 uint64_t SipHashX(SIPHASH_CTX *, int, int, const uint8_t[static SIPHASH_KEY_LENGTH], const void *, 79 size_t); 80 81 int SipHash24_TestVectors(void); 82 83 #endif /* _SIPHASH_H_ */ 84