xref: /openbsd/sys/crypto/siphash.h (revision e07278f2)
1*e07278f2Sdlg /*-
2*e07278f2Sdlg  * Copyright (c) 2013 Andre Oppermann <andre@FreeBSD.org>
3*e07278f2Sdlg  * All rights reserved.
4*e07278f2Sdlg  *
5*e07278f2Sdlg  * Redistribution and use in source and binary forms, with or without
6*e07278f2Sdlg  * modification, are permitted provided that the following conditions
7*e07278f2Sdlg  * are met:
8*e07278f2Sdlg  * 1. Redistributions of source code must retain the above copyright
9*e07278f2Sdlg  *    notice, this list of conditions and the following disclaimer.
10*e07278f2Sdlg  * 2. Redistributions in binary form must reproduce the above copyright
11*e07278f2Sdlg  *    notice, this list of conditions and the following disclaimer in the
12*e07278f2Sdlg  *    documentation and/or other materials provided with the distribution.
13*e07278f2Sdlg  * 3. The name of the author may not be used to endorse or promote
14*e07278f2Sdlg  *    products derived from this software without specific prior written
15*e07278f2Sdlg  *    permission.
16*e07278f2Sdlg  *
17*e07278f2Sdlg  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18*e07278f2Sdlg  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*e07278f2Sdlg  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*e07278f2Sdlg  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21*e07278f2Sdlg  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*e07278f2Sdlg  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*e07278f2Sdlg  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*e07278f2Sdlg  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*e07278f2Sdlg  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*e07278f2Sdlg  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*e07278f2Sdlg  * SUCH DAMAGE.
28*e07278f2Sdlg  *
29*e07278f2Sdlg  * $FreeBSD$
30*e07278f2Sdlg  */
31*e07278f2Sdlg 
32*e07278f2Sdlg /*
33*e07278f2Sdlg  * SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions)
34*e07278f2Sdlg  * optimized for speed on short messages returning a 64bit hash/digest value.
35*e07278f2Sdlg  *
36*e07278f2Sdlg  * The number of rounds is defined during the initialization:
37*e07278f2Sdlg  *  SipHash24_Init() for the fast and resonable strong version
38*e07278f2Sdlg  *  SipHash48_Init() for the strong version (half as fast)
39*e07278f2Sdlg  *
40*e07278f2Sdlg  * struct SIPHASH_CTX ctx;
41*e07278f2Sdlg  * SipHash24_Init(&ctx);
42*e07278f2Sdlg  * SipHash_SetKey(&ctx, "16bytes long key");
43*e07278f2Sdlg  * SipHash_Update(&ctx, pointer_to_string, length_of_string);
44*e07278f2Sdlg  * SipHash_Final(output, &ctx);
45*e07278f2Sdlg  */
46*e07278f2Sdlg 
47*e07278f2Sdlg #ifndef _SIPHASH_H_
48*e07278f2Sdlg #define _SIPHASH_H_
49*e07278f2Sdlg 
50*e07278f2Sdlg #define SIPHASH_BLOCK_LENGTH	 8
51*e07278f2Sdlg #define SIPHASH_KEY_LENGTH	16
52*e07278f2Sdlg #define SIPHASH_DIGEST_LENGTH	 8
53*e07278f2Sdlg 
54*e07278f2Sdlg typedef struct _SIPHASH_CTX {
55*e07278f2Sdlg 	u_int64_t	v[4];
56*e07278f2Sdlg 	u_int8_t	buf[SIPHASH_BLOCK_LENGTH];
57*e07278f2Sdlg 	u_int32_t	bytes;
58*e07278f2Sdlg } SIPHASH_CTX;
59*e07278f2Sdlg 
60*e07278f2Sdlg typedef struct {
61*e07278f2Sdlg 	u_int64_t	k0;
62*e07278f2Sdlg 	u_int64_t	k1;
63*e07278f2Sdlg } SIPHASH_KEY;
64*e07278f2Sdlg 
65*e07278f2Sdlg void		SipHash_Init(SIPHASH_CTX *, const SIPHASH_KEY *);
66*e07278f2Sdlg void		SipHash_Update(SIPHASH_CTX *, int, int, const void *, size_t);
67*e07278f2Sdlg u_int64_t	SipHash_End(SIPHASH_CTX *, int, int);
68*e07278f2Sdlg void		SipHash_Final(void *, SIPHASH_CTX *, int, int);
69*e07278f2Sdlg u_int64_t	SipHash(const SIPHASH_KEY *, int, int, const void *, size_t);
70*e07278f2Sdlg 
71*e07278f2Sdlg #define SipHash24_Init(_c, _k)		SipHash_Init((_c), (_k))
72*e07278f2Sdlg #define SipHash24_Update(_c, _p, _l)	SipHash_Update((_c), 2, 4, (_p), (_l))
73*e07278f2Sdlg #define SipHash24_End(_d)		SipHash_End((_d), 2, 4)
74*e07278f2Sdlg #define SipHash24_Final(_d, _c)		SipHash_Final((_d), (_c), 2, 4)
75*e07278f2Sdlg #define SipHash24(_k, _p, _l)		SipHash((_k), 2, 4, (_p), (_l))
76*e07278f2Sdlg 
77*e07278f2Sdlg #define SipHash48_Init(_c, _k)		SipHash_Init((_c), (_k))
78*e07278f2Sdlg #define SipHash48_Update(_c, _p, _l)	SipHash_Update((_c), 4, 8, (_p), (_l))
79*e07278f2Sdlg #define SipHash48_End(_d)		SipHash_End((_d), 4, 8)
80*e07278f2Sdlg #define SipHash48_Final(_d, _c)		SipHash_Final((_d), (_c), 4, 8)
81*e07278f2Sdlg #define SipHash48(_k, _p, _l)		SipHash((_k), 4, 8, (_p), (_l))
82*e07278f2Sdlg 
83*e07278f2Sdlg #endif /* _SIPHASH_H_ */
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