freebsd-nq/sys/crypto/siphash/siphash.h
Conrad Meyer 571ebf7685 crypto routines: Hint minimum buffer sizes to the compiler
Use the C99 'static' keyword to hint to the compiler IVs and output digest
sizes.  The keyword informs the compiler of the minimum valid size for a given
array.  Obviously not every pointer can be validated (i.e., the compiler can
produce false negative but not false positive reports).

No functional change.  No ABI change.

Sponsored by:	EMC / Isilon Storage Division
2016-05-26 19:29:29 +00:00

84 lines
3.1 KiB
C

/*-
* 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.
*
* $FreeBSD$
*/
/*
* SipHash is a family of pseudorandom functions (a.k.a. keyed hash functions)
* optimized for speed on short messages returning a 64bit hash/digest value.
*
* The number of rounds is defined during the initialization:
* SipHash24_Init() for the fast and resonable strong version
* SipHash48_Init() for the strong version (half as fast)
*
* struct SIPHASH_CTX ctx;
* SipHash24_Init(&ctx);
* SipHash_SetKey(&ctx, "16bytes long key");
* SipHash_Update(&ctx, pointer_to_string, length_of_string);
* SipHash_Final(output, &ctx);
*/
#ifndef _SIPHASH_H_
#define _SIPHASH_H_
#define SIPHASH_BLOCK_LENGTH 8
#define SIPHASH_KEY_LENGTH 16
#define SIPHASH_DIGEST_LENGTH 8
typedef struct _SIPHASH_CTX {
uint64_t v[4];
union {
uint64_t b64;
uint8_t b8[8];
} buf;
uint64_t bytes;
uint8_t buflen;
uint8_t rounds_compr;
uint8_t rounds_final;
uint8_t initialized;
} SIPHASH_CTX;
#define SipHash24_Init(x) SipHash_InitX((x), 2, 4)
#define SipHash48_Init(x) SipHash_InitX((x), 4, 8)
void SipHash_InitX(SIPHASH_CTX *, int, int);
void SipHash_SetKey(SIPHASH_CTX *, const uint8_t[static SIPHASH_KEY_LENGTH]);
void SipHash_Update(SIPHASH_CTX *, const void *, size_t);
void SipHash_Final(uint8_t[static SIPHASH_DIGEST_LENGTH], SIPHASH_CTX *);
uint64_t SipHash_End(SIPHASH_CTX *);
#define SipHash24(x, y, z, i) SipHashX((x), 2, 4, (y), (z), (i));
#define SipHash48(x, y, z, i) SipHashX((x), 4, 8, (y), (z), (i));
uint64_t SipHashX(SIPHASH_CTX *, int, int, const uint8_t[static SIPHASH_KEY_LENGTH], const void *,
size_t);
int SipHash24_TestVectors(void);
#endif /* _SIPHASH_H_ */