Andrew's git - gitweb.git/blob

5bf1b36bd18882b57c4953a1c9a5aa01d688944f
   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->lenW = 0;
  18        ctx->size = 0;
  19
  20        /* Initialize H with the magic constants (see FIPS180 for constants)
  21         */
  22        ctx->H[0] = 0x67452301;
  23        ctx->H[1] = 0xefcdab89;
  24        ctx->H[2] = 0x98badcfe;
  25        ctx->H[3] = 0x10325476;
  26        ctx->H[4] = 0xc3d2e1f0;
  27}
  28
  29
  30void blk_SHA1_Update(blk_SHA_CTX *ctx, const void *data, unsigned long len)
  31{
  32        int lenW = ctx->lenW;
  33
  34        ctx->size += (unsigned long long) len << 3;
  35
  36        /* Read the data into W and process blocks as they get full
  37         */
  38        if (lenW) {
  39                int left = 64 - lenW;
  40                if (len < left)
  41                        left = len;
  42                memcpy(lenW + (char *)ctx->W, data, left);
  43                lenW = (lenW + left) & 63;
  44                len -= left;
  45                data += left;
  46                ctx->lenW = lenW;
  47                if (lenW)
  48                        return;
  49                blk_SHA1Block(ctx, ctx->W);
  50        }
  51        while (len >= 64) {
  52                blk_SHA1Block(ctx, data);
  53                data += 64;
  54                len -= 64;
  55        }
  56        if (len) {
  57                memcpy(ctx->W, data, len);
  58                ctx->lenW = len;
  59        }
  60}
  61
  62
  63void blk_SHA1_Final(unsigned char hashout[20], blk_SHA_CTX *ctx)
  64{
  65        static const unsigned char pad[64] = { 0x80 };
  66        unsigned int padlen[2];
  67        int i;
  68
  69        /* Pad with a binary 1 (ie 0x80), then zeroes, then length
  70         */
  71        padlen[0] = htonl(ctx->size >> 32);
  72        padlen[1] = htonl(ctx->size);
  73
  74        blk_SHA1_Update(ctx, pad, 1+ (63 & (55 - ctx->lenW)));
  75        blk_SHA1_Update(ctx, padlen, 8);
  76
  77        /* Output hash
  78         */
  79        for (i = 0; i < 5; i++)
  80                ((unsigned int *)hashout)[i] = htonl(ctx->H[i]);
  81}
  82
  83#if defined(__i386__) || defined(__x86_64__)
  84
  85#define SHA_ASM(op, x, n) ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; })
  86#define SHA_ROL(x,n)    SHA_ASM("rol", x, n)
  87#define SHA_ROR(x,n)    SHA_ASM("ror", x, n)
  88
  89#else
  90
  91#define SHA_ROT(X,l,r)  (((X) << (l)) | ((X) >> (r)))
  92#define SHA_ROL(X,n)    SHA_ROT(X,n,32-(n))
  93#define SHA_ROR(X,n)    SHA_ROT(X,32-(n),n)
  94
  95#endif
  96
  97/* This "rolls" over the 512-bit array */
  98#define W(x) (array[(x)&15])
  99
 100/*
 101 * Where do we get the source from? The first 16 iterations get it from
 102 * the input data, the next mix it from the 512-bit array.
 103 */
 104#define SHA_SRC(t) htonl(data[t])
 105#define SHA_MIX(t) SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1)
 106
 107#define SHA_ROUND(t, input, fn, constant) \
 108        TEMP = input(t); W(t) = TEMP; \
 109        TEMP += SHA_ROL(A,5) + (fn) + E + (constant); \
 110        E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP
 111
 112#define T_0_15(t)  SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999 )
 113#define T_16_19(t) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999 )
 114#define T_20_39(t) SHA_ROUND(t, SHA_MIX, (B^C^D) , 0x6ed9eba1 )
 115#define T_40_59(t) SHA_ROUND(t, SHA_MIX, ((B&C)+(D&(B^C))) , 0x8f1bbcdc )
 116#define T_60_79(t) SHA_ROUND(t, SHA_MIX, (B^C^D) ,  0xca62c1d6 )
 117
 118static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data)
 119{
 120        unsigned int A,B,C,D,E,TEMP;
 121        unsigned int array[16];
 122
 123        A = ctx->H[0];
 124        B = ctx->H[1];
 125        C = ctx->H[2];
 126        D = ctx->H[3];
 127        E = ctx->H[4];
 128
 129        /* Round 1 - iterations 0-16 take their input from 'data' */
 130        T_0_15( 0); T_0_15( 1); T_0_15( 2); T_0_15( 3); T_0_15( 4);
 131        T_0_15( 5); T_0_15( 6); T_0_15( 7); T_0_15( 8); T_0_15( 9);
 132        T_0_15(10); T_0_15(11); T_0_15(12); T_0_15(13); T_0_15(14);
 133        T_0_15(15);
 134
 135        /* Round 1 - tail. Input from 512-bit mixing array */
 136        T_16_19(16); T_16_19(17); T_16_19(18); T_16_19(19);
 137
 138        /* Round 2 */
 139        T_20_39(20); T_20_39(21); T_20_39(22); T_20_39(23); T_20_39(24);
 140        T_20_39(25); T_20_39(26); T_20_39(27); T_20_39(28); T_20_39(29);
 141        T_20_39(30); T_20_39(31); T_20_39(32); T_20_39(33); T_20_39(34);
 142        T_20_39(35); T_20_39(36); T_20_39(37); T_20_39(38); T_20_39(39);
 143
 144        /* Round 3 */
 145        T_40_59(40); T_40_59(41); T_40_59(42); T_40_59(43); T_40_59(44);
 146        T_40_59(45); T_40_59(46); T_40_59(47); T_40_59(48); T_40_59(49);
 147        T_40_59(50); T_40_59(51); T_40_59(52); T_40_59(53); T_40_59(54);
 148        T_40_59(55); T_40_59(56); T_40_59(57); T_40_59(58); T_40_59(59);
 149
 150        /* Round 4 */
 151        T_60_79(60); T_60_79(61); T_60_79(62); T_60_79(63); T_60_79(64);
 152        T_60_79(65); T_60_79(66); T_60_79(67); T_60_79(68); T_60_79(69);
 153        T_60_79(70); T_60_79(71); T_60_79(72); T_60_79(73); T_60_79(74);
 154        T_60_79(75); T_60_79(76); T_60_79(77); T_60_79(78); T_60_79(79);
 155
 156        ctx->H[0] += A;
 157        ctx->H[1] += B;
 158        ctx->H[2] += C;
 159        ctx->H[3] += D;
 160        ctx->H[4] += E;
 161}