xref: /xnu-12377.81.4/bsd/net/siphash.h (revision 043036a2b3718f7f0be807e2870f8f47d3fa0796)
1 /*-
2  * Copyright (c) 2013 Andre Oppermann <[email protected]>
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 
30 /*
31  * SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions)
32  * optimized for speed on short messages returning a 64bit hash/digest value.
33  *
34  * The number of rounds is defined during the initialization:
35  *  SipHash24_Init() for the fast and resonable strong version
36  *  SipHash48_Init() for the strong version (half as fast)
37  *
38  * struct SIPHASH_CTX ctx;
39  * SipHash24_Init(&ctx);
40  * SipHash_SetKey(&ctx, "16bytes long key");
41  * SipHash_Update(&ctx, pointer_to_string, length_of_string);
42  * SipHash_Final(output, &ctx);
43  */
44 
45 #ifndef _NET_SIPHASH_H_
46 #define _NET_SIPHASH_H_
47 
48 #include <sys/types.h>
49 #include <stdint.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 	union {
58 		uint64_t        b64;
59 		uint8_t         b8[8];
60 	} buf;
61 	uint64_t        bytes;
62 	uint8_t         buflen;
63 	uint8_t         rounds_compr;
64 	uint8_t         rounds_final;
65 	uint8_t         initialized;
66 } SIPHASH_CTX;
67 
68 
69 #define SipHash24_Init(x)       SipHash_InitX((x), 2, 4)
70 #define SipHash48_Init(x)       SipHash_InitX((x), 4, 8)
71 void SipHash_InitX(SIPHASH_CTX *, uint8_t, uint8_t);
72 void SipHash_SetKey(SIPHASH_CTX *,
73     const uint8_t[SIPHASH_KEY_LENGTH]);
74 void SipHash_Update(SIPHASH_CTX *ctx, const void *src __sized_by(len0), size_t len0);
75 void SipHash_Final(uint8_t[SIPHASH_DIGEST_LENGTH], SIPHASH_CTX *);
76 uint64_t SipHash_End(SIPHASH_CTX *);
77 
78 #define SipHash24(x, y, z, i)   SipHashX((x), 2, 4, (y), (z), (i));
79 #define SipHash48(x, y, z, i)   SipHashX((x), 4, 8, (y), (z), (i));
80 uint64_t SipHashX(SIPHASH_CTX *ctx, uint8_t rc, uint8_t rf,
81     const uint8_t key[SIPHASH_KEY_LENGTH], const void *src __sized_by(len), size_t len);
82 
83 int SipHash24_TestVectors(void);
84 
85 #endif /* _SIPHASH_H_ */
86