1 /* 2 * Platform-specific definitions for Skein hash function. 3 * 4 * Source code author: Doug Whiting, 2008. 5 * 6 * This algorithm and source code is released to the public domain. 7 * 8 * Many thanks to Brian Gladman for his portable header files. 9 * 10 * To port Skein to an "unsupported" platform, change the definitions 11 * in this file appropriately. 12 */ 13 /* Copyright 2013 Doug Whiting. This code is released to the public domain. */ 14 15 #ifndef _SKEIN_PORT_H_ 16 #define _SKEIN_PORT_H_ 17 18 #include <sys/types.h> /* get integer type definitions */ 19 20 #ifndef RotL_64 21 #define RotL_64(x, N) (((x) << (N)) | ((x) >> (64 - (N)))) 22 #endif 23 24 /* 25 * Skein is "natively" little-endian (unlike SHA-xxx), for optimal 26 * performance on x86 CPUs. The Skein code requires the following 27 * definitions for dealing with endianness: 28 * 29 * SKEIN_NEED_SWAP: 0 for little-endian, 1 for big-endian 30 * Skein_Put64_LSB_First 31 * Skein_Get64_LSB_First 32 * Skein_Swap64 33 * 34 * If SKEIN_NEED_SWAP is defined at compile time, it is used here 35 * along with the portable versions of Put64/Get64/Swap64, which 36 * are slow in general. 37 * 38 * Otherwise, an "auto-detect" of endianness is attempted below. 39 * If the default handling doesn't work well, the user may insert 40 * platform-specific code instead (e.g., for big-endian CPUs). 41 * 42 */ 43 #ifndef SKEIN_NEED_SWAP /* compile-time "override" for endianness? */ 44 45 #include <sys/isa_defs.h> /* get endianness selection */ 46 47 #if defined(_ZFS_BIG_ENDIAN) 48 /* here for big-endian CPUs */ 49 #define SKEIN_NEED_SWAP (1) 50 #else 51 /* here for x86 and x86-64 CPUs (and other detected little-endian CPUs) */ 52 #define SKEIN_NEED_SWAP (0) 53 #define Skein_Put64_LSB_First(dst08, src64, bCnt) memcpy(dst08, src64, bCnt) 54 #define Skein_Get64_LSB_First(dst64, src08, wCnt) \ 55 memcpy(dst64, src08, 8 * (wCnt)) 56 #endif 57 58 #endif /* ifndef SKEIN_NEED_SWAP */ 59 60 /* 61 * Provide any definitions still needed. 62 */ 63 #ifndef Skein_Swap64 /* swap for big-endian, nop for little-endian */ 64 #if SKEIN_NEED_SWAP 65 #define Skein_Swap64(w64) \ 66 (((((uint64_t)(w64)) & 0xFF) << 56) | \ 67 (((((uint64_t)(w64)) >> 8) & 0xFF) << 48) | \ 68 (((((uint64_t)(w64)) >> 16) & 0xFF) << 40) | \ 69 (((((uint64_t)(w64)) >> 24) & 0xFF) << 32) | \ 70 (((((uint64_t)(w64)) >> 32) & 0xFF) << 24) | \ 71 (((((uint64_t)(w64)) >> 40) & 0xFF) << 16) | \ 72 (((((uint64_t)(w64)) >> 48) & 0xFF) << 8) | \ 73 (((((uint64_t)(w64)) >> 56) & 0xFF))) 74 #else 75 #define Skein_Swap64(w64) (w64) 76 #endif 77 #endif /* ifndef Skein_Swap64 */ 78 79 #ifndef Skein_Put64_LSB_First 80 static inline void 81 Skein_Put64_LSB_First(uint8_t *dst, const uint64_t *src, size_t bCnt) 82 { 83 /* 84 * this version is fully portable (big-endian or little-endian), 85 * but slow 86 */ 87 size_t n; 88 89 for (n = 0; n < bCnt; n++) 90 dst[n] = (uint8_t)(src[n >> 3] >> (8 * (n & 7))); 91 } 92 #endif /* ifndef Skein_Put64_LSB_First */ 93 94 #ifndef Skein_Get64_LSB_First 95 static inline void 96 Skein_Get64_LSB_First(uint64_t *dst, const uint8_t *src, size_t wCnt) 97 { 98 /* 99 * this version is fully portable (big-endian or little-endian), 100 * but slow 101 */ 102 size_t n; 103 104 for (n = 0; n < 8 * wCnt; n += 8) 105 dst[n / 8] = (((uint64_t)src[n])) + 106 (((uint64_t)src[n + 1]) << 8) + 107 (((uint64_t)src[n + 2]) << 16) + 108 (((uint64_t)src[n + 3]) << 24) + 109 (((uint64_t)src[n + 4]) << 32) + 110 (((uint64_t)src[n + 5]) << 40) + 111 (((uint64_t)src[n + 6]) << 48) + 112 (((uint64_t)src[n + 7]) << 56); 113 } 114 #endif /* ifndef Skein_Get64_LSB_First */ 115 116 #endif /* _SKEIN_PORT_H_ */ 117