Andrew's git - gitweb.git/blob

50b2b42b03f255689b26cc91d7fb02ce5601dff2
   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 += len;
  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 - 3));
  72        padlen[1] = htonl(ctx->size << 3);
  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#define SHA_ROT(X,n) (((X) << (n)) | ((X) >> (32-(n))))
  84
  85static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data)
  86{
  87        int t;
  88        unsigned int A,B,C,D,E,TEMP;
  89        unsigned int W[80];
  90
  91        for (t = 0; t < 16; t++)
  92                W[t] = htonl(data[t]);
  93
  94        /* Unroll it? */
  95        for (t = 16; t <= 79; t++)
  96                W[t] = SHA_ROT(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16], 1);
  97
  98        A = ctx->H[0];
  99        B = ctx->H[1];
 100        C = ctx->H[2];
 101        D = ctx->H[3];
 102        E = ctx->H[4];
 103
 104#define T_0_19(t) \
 105        TEMP = SHA_ROT(A,5) + (((C^D)&B)^D)     + E + W[t] + 0x5a827999; \
 106        E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
 107
 108        T_0_19( 0); T_0_19( 1); T_0_19( 2); T_0_19( 3); T_0_19( 4);
 109        T_0_19( 5); T_0_19( 6); T_0_19( 7); T_0_19( 8); T_0_19( 9);
 110        T_0_19(10); T_0_19(11); T_0_19(12); T_0_19(13); T_0_19(14);
 111        T_0_19(15); T_0_19(16); T_0_19(17); T_0_19(18); T_0_19(19);
 112
 113#define T_20_39(t) \
 114        TEMP = SHA_ROT(A,5) + (B^C^D)           + E + W[t] + 0x6ed9eba1; \
 115        E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
 116
 117        T_20_39(20); T_20_39(21); T_20_39(22); T_20_39(23); T_20_39(24);
 118        T_20_39(25); T_20_39(26); T_20_39(27); T_20_39(28); T_20_39(29);
 119        T_20_39(30); T_20_39(31); T_20_39(32); T_20_39(33); T_20_39(34);
 120        T_20_39(35); T_20_39(36); T_20_39(37); T_20_39(38); T_20_39(39);
 121
 122#define T_40_59(t) \
 123        TEMP = SHA_ROT(A,5) + ((B&C)|(D&(B|C))) + E + W[t] + 0x8f1bbcdc; \
 124        E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
 125
 126        T_40_59(40); T_40_59(41); T_40_59(42); T_40_59(43); T_40_59(44);
 127        T_40_59(45); T_40_59(46); T_40_59(47); T_40_59(48); T_40_59(49);
 128        T_40_59(50); T_40_59(51); T_40_59(52); T_40_59(53); T_40_59(54);
 129        T_40_59(55); T_40_59(56); T_40_59(57); T_40_59(58); T_40_59(59);
 130
 131#define T_60_79(t) \
 132        TEMP = SHA_ROT(A,5) + (B^C^D)           + E + W[t] + 0xca62c1d6; \
 133        E = D; D = C; C = SHA_ROT(B, 30); B = A; A = TEMP;
 134
 135        T_60_79(60); T_60_79(61); T_60_79(62); T_60_79(63); T_60_79(64);
 136        T_60_79(65); T_60_79(66); T_60_79(67); T_60_79(68); T_60_79(69);
 137        T_60_79(70); T_60_79(71); T_60_79(72); T_60_79(73); T_60_79(74);
 138        T_60_79(75); T_60_79(76); T_60_79(77); T_60_79(78); T_60_79(79);
 139
 140        ctx->H[0] += A;
 141        ctx->H[1] += B;
 142        ctx->H[2] += C;
 143        ctx->H[3] += D;
 144        ctx->H[4] += E;
 145}