pcompress/crypto/skein/skein_port.h
Moinak Ghosh eda312ce1e Add support for Skein512 and Skein256 checksums
Import Skein code from NIST CD submission
Make checksum algorithms pluggable
Fix handling of huge buffers (>2GB) in LZP
Cleanup of some buffer sizing code
Speed up CRC64 calculation in dedupe chunking
2012-08-31 22:36:06 +05:30

124 lines
4.5 KiB
C

#ifndef _SKEIN_PORT_H_
#define _SKEIN_PORT_H_
/*******************************************************************
**
** Platform-specific definitions for Skein hash function.
**
** Source code author: Doug Whiting, 2008.
**
** This algorithm and source code is released to the public domain.
**
** Many thanks to Brian Gladman for his portable header files.
**
** To port Skein to an "unsupported" platform, change the definitions
** in this file appropriately.
**
********************************************************************/
#include "brg_types.h" /* get integer type definitions */
typedef unsigned int uint_t; /* native unsigned integer */
typedef uint_8t u08b_t; /* 8-bit unsigned integer */
typedef uint_64t u64b_t; /* 64-bit unsigned integer */
#ifndef RotL_64
#define RotL_64(x,N) (((x) << (N)) | ((x) >> (64-(N))))
#endif
/*
* Skein is "natively" little-endian (unlike SHA-xxx), for optimal
* performance on x86 CPUs. The Skein code requires the following
* definitions for dealing with endianness:
*
* SKEIN_NEED_SWAP: 0 for little-endian, 1 for big-endian
* Skein_Put64_LSB_First
* Skein_Get64_LSB_First
* Skein_Swap64
*
* If SKEIN_NEED_SWAP is defined at compile time, it is used here
* along with the portable versions of Put64/Get64/Swap64, which
* are slow in general.
*
* Otherwise, an "auto-detect" of endianness is attempted below.
* If the default handling doesn't work well, the user may insert
* platform-specific code instead (e.g., for big-endian CPUs).
*
*/
#ifndef SKEIN_NEED_SWAP /* compile-time "override" for endianness? */
#include "brg_endian.h" /* get endianness selection */
#if PLATFORM_BYTE_ORDER == IS_BIG_ENDIAN
/* here for big-endian CPUs */
#define SKEIN_NEED_SWAP (1)
#elif PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN
/* here for x86 and x86-64 CPUs (and other detected little-endian CPUs) */
#define SKEIN_NEED_SWAP (0)
#if PLATFORM_MUST_ALIGN == 0 /* ok to use "fast" versions? */
#define Skein_Put64_LSB_First(dst08,src64,bCnt) memcpy(dst08,src64,bCnt)
#define Skein_Get64_LSB_First(dst64,src08,wCnt) memcpy(dst64,src08,8*(wCnt))
#endif
#else
#error "Skein needs endianness setting!"
#endif
#endif /* ifndef SKEIN_NEED_SWAP */
/*
******************************************************************
* Provide any definitions still needed.
******************************************************************
*/
#ifndef Skein_Swap64 /* swap for big-endian, nop for little-endian */
#if SKEIN_NEED_SWAP
#define Skein_Swap64(w64) \
( (( ((u64b_t)(w64)) & 0xFF) << 56) | \
(((((u64b_t)(w64)) >> 8) & 0xFF) << 48) | \
(((((u64b_t)(w64)) >>16) & 0xFF) << 40) | \
(((((u64b_t)(w64)) >>24) & 0xFF) << 32) | \
(((((u64b_t)(w64)) >>32) & 0xFF) << 24) | \
(((((u64b_t)(w64)) >>40) & 0xFF) << 16) | \
(((((u64b_t)(w64)) >>48) & 0xFF) << 8) | \
(((((u64b_t)(w64)) >>56) & 0xFF) ) )
#else
#define Skein_Swap64(w64) (w64)
#endif
#endif /* ifndef Skein_Swap64 */
#ifndef Skein_Put64_LSB_First
void Skein_Put64_LSB_First(u08b_t *dst,const u64b_t *src,size_t bCnt)
#ifdef SKEIN_PORT_CODE /* instantiate the function code here? */
{ /* this version is fully portable (big-endian or little-endian), but slow */
size_t n;
for (n=0;n<bCnt;n++)
dst[n] = (u08b_t) (src[n>>3] >> (8*(n&7)));
}
#else
; /* output only the function prototype */
#endif
#endif /* ifndef Skein_Put64_LSB_First */
#ifndef Skein_Get64_LSB_First
void Skein_Get64_LSB_First(u64b_t *dst,const u08b_t *src,size_t wCnt)
#ifdef SKEIN_PORT_CODE /* instantiate the function code here? */
{ /* this version is fully portable (big-endian or little-endian), but slow */
size_t n;
for (n=0;n<8*wCnt;n+=8)
dst[n/8] = (((u64b_t) src[n ]) ) +
(((u64b_t) src[n+1]) << 8) +
(((u64b_t) src[n+2]) << 16) +
(((u64b_t) src[n+3]) << 24) +
(((u64b_t) src[n+4]) << 32) +
(((u64b_t) src[n+5]) << 40) +
(((u64b_t) src[n+6]) << 48) +
(((u64b_t) src[n+7]) << 56) ;
}
#else
; /* output only the function prototype */
#endif
#endif /* ifndef Skein_Get64_LSB_First */
#endif /* ifndef _SKEIN_PORT_H_ */