1/* 2 * Based on the Mozilla SHA1 (see mozilla-sha1/sha1.c), 3 * optimized to do word accesses rather than byte accesses, 4 * and to avoid unnecessary copies into the context array. 5 */ 6 7#include <string.h> 8#include <arpa/inet.h> 9 10#include "sha1.h" 11 12/* Hash one 64-byte block of data */ 13static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data); 14 15void blk_SHA1_Init(blk_SHA_CTX *ctx) 16{ 17 ctx->size = 0; 18 19 /* Initialize H with the magic constants (see FIPS180 for constants) 20 */ 21 ctx->H[0] = 0x67452301; 22 ctx->H[1] = 0xefcdab89; 23 ctx->H[2] = 0x98badcfe; 24 ctx->H[3] = 0x10325476; 25 ctx->H[4] = 0xc3d2e1f0; 26} 27 28 29void blk_SHA1_Update(blk_SHA_CTX *ctx, const void *data, unsigned long len) 30{ 31 int lenW = ctx->size & 63; 32 33 ctx->size += len; 34 35 /* Read the data into W and process blocks as they get full 36 */ 37 if (lenW) { 38 int left = 64 - lenW; 39 if (len < left) 40 left = len; 41 memcpy(lenW + (char *)ctx->W, data, left); 42 lenW = (lenW + left) & 63; 43 len -= left; 44 data += left; 45 if (lenW) 46 return; 47 blk_SHA1Block(ctx, ctx->W); 48 } 49 while (len >= 64) { 50 blk_SHA1Block(ctx, data); 51 data += 64; 52 len -= 64; 53 } 54 if (len) 55 memcpy(ctx->W, data, len); 56} 57 58 59void blk_SHA1_Final(unsigned char hashout[20], blk_SHA_CTX *ctx) 60{ 61 static const unsigned char pad[64] = { 0x80 }; 62 unsigned int padlen[2]; 63 int i; 64 65 /* Pad with a binary 1 (ie 0x80), then zeroes, then length 66 */ 67 padlen[0] = htonl(ctx->size >> 29); 68 padlen[1] = htonl(ctx->size << 3); 69 70 i = ctx->size & 63; 71 blk_SHA1_Update(ctx, pad, 1+ (63 & (55 - i))); 72 blk_SHA1_Update(ctx, padlen, 8); 73 74 /* Output hash 75 */ 76 for (i = 0; i < 5; i++) 77 ((unsigned int *)hashout)[i] = htonl(ctx->H[i]); 78} 79 80#if defined(__i386__) || defined(__x86_64__) 81 82#define SHA_ASM(op, x, n) ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; }) 83#define SHA_ROL(x,n) SHA_ASM("rol", x, n) 84#define SHA_ROR(x,n) SHA_ASM("ror", x, n) 85#define SMALL_REGISTER_SET 86 87#else 88 89#define SHA_ROT(X,l,r) (((X) << (l)) | ((X) >> (r))) 90#define SHA_ROL(X,n) SHA_ROT(X,n,32-(n)) 91#define SHA_ROR(X,n) SHA_ROT(X,32-(n),n) 92 93#endif 94 95/* This "rolls" over the 512-bit array */ 96#define W(x) (array[(x)&15]) 97 98/* 99 * If you have 32 registers or more, the compiler can (and should) 100 * try to change the array[] accesses into registers. However, on 101 * machines with less than ~25 registers, that won't really work, 102 * and at least gcc will make an unholy mess of it. 103 * 104 * So to avoid that mess which just slows things down, we force 105 * the stores to memory to actually happen (we might be better off 106 * with a 'W(t)=(val);asm("":"+m" (W(t))' there instead, as 107 * suggested by Artur Skawina - that will also make gcc unable to 108 * try to do the silly "optimize away loads" part because it won't 109 * see what the value will be). 110 * 111 * Ben Herrenschmidt reports that on PPC, the C version comes close 112 * to the optimized asm with this (ie on PPC you don't want that 113 * 'volatile', since there are lots of registers). 114 */ 115#ifdef SMALL_REGISTER_SET 116 #define setW(x, val) (*(volatile unsigned int *)&W(x) = (val)) 117#else 118 #define setW(x, val) (W(x) = (val)) 119#endif 120 121/* 122 * Where do we get the source from? The first 16 iterations get it from 123 * the input data, the next mix it from the 512-bit array. 124 */ 125#define SHA_SRC(t) htonl(data[t]) 126#define SHA_MIX(t) SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1) 127 128#define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \ 129 unsigned int TEMP = input(t); setW(t, TEMP); \ 130 E += TEMP + SHA_ROL(A,5) + (fn) + (constant); \ 131 B = SHA_ROR(B, 2); } while (0) 132 133#define T_0_15(t, A, B, C, D, E) SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) 134#define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) 135#define T_20_39(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1, A, B, C, D, E ) 136#define T_40_59(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc, A, B, C, D, E ) 137#define T_60_79(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0xca62c1d6, A, B, C, D, E ) 138 139static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data) 140{ 141 unsigned int A,B,C,D,E; 142 unsigned int array[16]; 143 144 A = ctx->H[0]; 145 B = ctx->H[1]; 146 C = ctx->H[2]; 147 D = ctx->H[3]; 148 E = ctx->H[4]; 149 150 /* Round 1 - iterations 0-16 take their input from 'data' */ 151 T_0_15( 0, A, B, C, D, E); 152 T_0_15( 1, E, A, B, C, D); 153 T_0_15( 2, D, E, A, B, C); 154 T_0_15( 3, C, D, E, A, B); 155 T_0_15( 4, B, C, D, E, A); 156 T_0_15( 5, A, B, C, D, E); 157 T_0_15( 6, E, A, B, C, D); 158 T_0_15( 7, D, E, A, B, C); 159 T_0_15( 8, C, D, E, A, B); 160 T_0_15( 9, B, C, D, E, A); 161 T_0_15(10, A, B, C, D, E); 162 T_0_15(11, E, A, B, C, D); 163 T_0_15(12, D, E, A, B, C); 164 T_0_15(13, C, D, E, A, B); 165 T_0_15(14, B, C, D, E, A); 166 T_0_15(15, A, B, C, D, E); 167 168 /* Round 1 - tail. Input from 512-bit mixing array */ 169 T_16_19(16, E, A, B, C, D); 170 T_16_19(17, D, E, A, B, C); 171 T_16_19(18, C, D, E, A, B); 172 T_16_19(19, B, C, D, E, A); 173 174 /* Round 2 */ 175 T_20_39(20, A, B, C, D, E); 176 T_20_39(21, E, A, B, C, D); 177 T_20_39(22, D, E, A, B, C); 178 T_20_39(23, C, D, E, A, B); 179 T_20_39(24, B, C, D, E, A); 180 T_20_39(25, A, B, C, D, E); 181 T_20_39(26, E, A, B, C, D); 182 T_20_39(27, D, E, A, B, C); 183 T_20_39(28, C, D, E, A, B); 184 T_20_39(29, B, C, D, E, A); 185 T_20_39(30, A, B, C, D, E); 186 T_20_39(31, E, A, B, C, D); 187 T_20_39(32, D, E, A, B, C); 188 T_20_39(33, C, D, E, A, B); 189 T_20_39(34, B, C, D, E, A); 190 T_20_39(35, A, B, C, D, E); 191 T_20_39(36, E, A, B, C, D); 192 T_20_39(37, D, E, A, B, C); 193 T_20_39(38, C, D, E, A, B); 194 T_20_39(39, B, C, D, E, A); 195 196 /* Round 3 */ 197 T_40_59(40, A, B, C, D, E); 198 T_40_59(41, E, A, B, C, D); 199 T_40_59(42, D, E, A, B, C); 200 T_40_59(43, C, D, E, A, B); 201 T_40_59(44, B, C, D, E, A); 202 T_40_59(45, A, B, C, D, E); 203 T_40_59(46, E, A, B, C, D); 204 T_40_59(47, D, E, A, B, C); 205 T_40_59(48, C, D, E, A, B); 206 T_40_59(49, B, C, D, E, A); 207 T_40_59(50, A, B, C, D, E); 208 T_40_59(51, E, A, B, C, D); 209 T_40_59(52, D, E, A, B, C); 210 T_40_59(53, C, D, E, A, B); 211 T_40_59(54, B, C, D, E, A); 212 T_40_59(55, A, B, C, D, E); 213 T_40_59(56, E, A, B, C, D); 214 T_40_59(57, D, E, A, B, C); 215 T_40_59(58, C, D, E, A, B); 216 T_40_59(59, B, C, D, E, A); 217 218 /* Round 4 */ 219 T_60_79(60, A, B, C, D, E); 220 T_60_79(61, E, A, B, C, D); 221 T_60_79(62, D, E, A, B, C); 222 T_60_79(63, C, D, E, A, B); 223 T_60_79(64, B, C, D, E, A); 224 T_60_79(65, A, B, C, D, E); 225 T_60_79(66, E, A, B, C, D); 226 T_60_79(67, D, E, A, B, C); 227 T_60_79(68, C, D, E, A, B); 228 T_60_79(69, B, C, D, E, A); 229 T_60_79(70, A, B, C, D, E); 230 T_60_79(71, E, A, B, C, D); 231 T_60_79(72, D, E, A, B, C); 232 T_60_79(73, C, D, E, A, B); 233 T_60_79(74, B, C, D, E, A); 234 T_60_79(75, A, B, C, D, E); 235 T_60_79(76, E, A, B, C, D); 236 T_60_79(77, D, E, A, B, C); 237 T_60_79(78, C, D, E, A, B); 238 T_60_79(79, B, C, D, E, A); 239 240 ctx->H[0] += A; 241 ctx->H[1] += B; 242 ctx->H[2] += C; 243 ctx->H[3] += D; 244 ctx->H[4] += E; 245}