lib/sha1.c

   1 /*
   2  * SHA-1 in C by Steve Reid <steve@edmweb.com>
   3  * 100% Public Domain
   4  *
   5  * Test Vectors (from FIPS PUB 180-1)
   6  * 1) "abc": A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
   7  * 2) "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq":  84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
   8  * 3) A million repetitions of "a":  34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
   9  */
  10
  11 #define UL_SHA1HANDSOFF
  12
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <stdint.h>
  16
  17 #include "sha1.h"
  18
  19 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  20
  21 /* blk0() and blk() perform the initial expand. */
  22 #ifdef WORDS_BIGENDIAN
  23 # define blk0(i) block->l[i]
  24 #else
  25 # define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
  26     |(rol(block->l[i],8)&0x00FF00FF))
  27 #endif
  28
  29 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
  30     ^block->l[(i+2)&15]^block->l[i&15],1))
  31
  32 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  33 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  34 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  35 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  36 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  37 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  38
  39 /* Hash a single 512-bit block. This is the core of the algorithm. */
  40
  41 void ul_SHA1Transform(uint32_t state[5], const unsigned char buffer[64])
  42 {
  43         uint32_t a, b, c, d, e;
  44
  45         typedef union {
  46                 unsigned char c[64];
  47                 uint32_t l[16];
  48         } CHAR64LONG16;
  49
  50 #ifdef UL_SHA1HANDSOFF
  51         CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  52
  53         memcpy(block, buffer, 64);
  54 #else
  55         /* The following had better never be used because it causes the
  56          * pointer-to-const buffer to be cast into a pointer to non-const.
  57          * And the result is written through.  I threw a "const" in, hoping
  58          * this will cause a diagnostic.
  59          */
  60         CHAR64LONG16 *block = (const CHAR64LONG16 *)buffer;
  61 #endif
  62         /* Copy context->state[] to working vars */
  63         a = state[0];
  64         b = state[1];
  65         c = state[2];
  66         d = state[3];
  67         e = state[4];
  68         /* 4 rounds of 20 operations each. Loop unrolled. */
  69         R0(a, b, c, d, e, 0);
  70         R0(e, a, b, c, d, 1);
  71         R0(d, e, a, b, c, 2);
  72         R0(c, d, e, a, b, 3);
  73         R0(b, c, d, e, a, 4);
  74         R0(a, b, c, d, e, 5);
  75         R0(e, a, b, c, d, 6);
  76         R0(d, e, a, b, c, 7);
  77         R0(c, d, e, a, b, 8);
  78         R0(b, c, d, e, a, 9);
  79         R0(a, b, c, d, e, 10);
  80         R0(e, a, b, c, d, 11);
  81         R0(d, e, a, b, c, 12);
  82         R0(c, d, e, a, b, 13);
  83         R0(b, c, d, e, a, 14);
  84         R0(a, b, c, d, e, 15);
  85         R1(e, a, b, c, d, 16);
  86         R1(d, e, a, b, c, 17);
  87         R1(c, d, e, a, b, 18);
  88         R1(b, c, d, e, a, 19);
  89         R2(a, b, c, d, e, 20);
  90         R2(e, a, b, c, d, 21);
  91         R2(d, e, a, b, c, 22);
  92         R2(c, d, e, a, b, 23);
  93         R2(b, c, d, e, a, 24);
  94         R2(a, b, c, d, e, 25);
  95         R2(e, a, b, c, d, 26);
  96         R2(d, e, a, b, c, 27);
  97         R2(c, d, e, a, b, 28);
  98         R2(b, c, d, e, a, 29);
  99         R2(a, b, c, d, e, 30);
 100         R2(e, a, b, c, d, 31);
 101         R2(d, e, a, b, c, 32);
 102         R2(c, d, e, a, b, 33);
 103         R2(b, c, d, e, a, 34);
 104         R2(a, b, c, d, e, 35);
 105         R2(e, a, b, c, d, 36);
 106         R2(d, e, a, b, c, 37);
 107         R2(c, d, e, a, b, 38);
 108         R2(b, c, d, e, a, 39);
 109         R3(a, b, c, d, e, 40);
 110         R3(e, a, b, c, d, 41);
 111         R3(d, e, a, b, c, 42);
 112         R3(c, d, e, a, b, 43);
 113         R3(b, c, d, e, a, 44);
 114         R3(a, b, c, d, e, 45);
 115         R3(e, a, b, c, d, 46);
 116         R3(d, e, a, b, c, 47);
 117         R3(c, d, e, a, b, 48);
 118         R3(b, c, d, e, a, 49);
 119         R3(a, b, c, d, e, 50);
 120         R3(e, a, b, c, d, 51);
 121         R3(d, e, a, b, c, 52);
 122         R3(c, d, e, a, b, 53);
 123         R3(b, c, d, e, a, 54);
 124         R3(a, b, c, d, e, 55);
 125         R3(e, a, b, c, d, 56);
 126         R3(d, e, a, b, c, 57);
 127         R3(c, d, e, a, b, 58);
 128         R3(b, c, d, e, a, 59);
 129         R4(a, b, c, d, e, 60);
 130         R4(e, a, b, c, d, 61);
 131         R4(d, e, a, b, c, 62);
 132         R4(c, d, e, a, b, 63);
 133         R4(b, c, d, e, a, 64);
 134         R4(a, b, c, d, e, 65);
 135         R4(e, a, b, c, d, 66);
 136         R4(d, e, a, b, c, 67);
 137         R4(c, d, e, a, b, 68);
 138         R4(b, c, d, e, a, 69);
 139         R4(a, b, c, d, e, 70);
 140         R4(e, a, b, c, d, 71);
 141         R4(d, e, a, b, c, 72);
 142         R4(c, d, e, a, b, 73);
 143         R4(b, c, d, e, a, 74);
 144         R4(a, b, c, d, e, 75);
 145         R4(e, a, b, c, d, 76);
 146         R4(d, e, a, b, c, 77);
 147         R4(c, d, e, a, b, 78);
 148         R4(b, c, d, e, a, 79);
 149         /* Add the working vars back into context.state[] */
 150         state[0] += a;
 151         state[1] += b;
 152         state[2] += c;
 153         state[3] += d;
 154         state[4] += e;
 155         /* Wipe variables */
 156         a = b = c = d = e = 0;
 157 #ifdef UL_SHA1HANDSOFF
 158         memset(block, '\0', sizeof(block));
 159 #endif
 160 }
 161
 162 /* SHA1Init - Initialize new context */
 163
 164 void ul_SHA1Init(UL_SHA1_CTX *context)
 165 {
 166         /* SHA1 initialization constants */
 167         context->state[0] = 0x67452301;
 168         context->state[1] = 0xEFCDAB89;
 169         context->state[2] = 0x98BADCFE;
 170         context->state[3] = 0x10325476;
 171         context->state[4] = 0xC3D2E1F0;
 172         context->count[0] = context->count[1] = 0;
 173 }
 174
 175 /* Run your data through this. */
 176
 177 void ul_SHA1Update(UL_SHA1_CTX *context, const unsigned char *data, uint32_t len)
 178 {
 179         uint32_t i;
 180
 181         uint32_t j;
 182
 183         j = context->count[0];
 184         if ((context->count[0] += len << 3) < j)
 185                 context->count[1]++;
 186         context->count[1] += (len >> 29);
 187         j = (j >> 3) & 63;
 188         if ((j + len) > 63) {
 189                 memcpy(&context->buffer[j], data, (i = 64 - j));
 190                 ul_SHA1Transform(context->state, context->buffer);
 191                 for (; i + 63 < len; i += 64) {
 192                         ul_SHA1Transform(context->state, &data[i]);
 193                 }
 194                 j = 0;
 195         } else
 196                 i = 0;
 197         memcpy(&context->buffer[j], &data[i], len - i);
 198 }
 199
 200 /* Add padding and return the message digest. */
 201
 202 void ul_SHA1Final(unsigned char digest[20], UL_SHA1_CTX *context)
 203 {
 204         unsigned i;
 205
 206         unsigned char finalcount[8];
 207
 208         unsigned char c;
 209
 210 #if 0                           /* untested "improvement" by DHR */
 211         /* Convert context->count to a sequence of bytes
 212          * in finalcount.  Second element first, but
 213          * big-endian order within element.
 214          * But we do it all backwards.
 215          */
 216         unsigned char *fcp = &finalcount[8];
 217
 218         for (i = 0; i < 2; i++) {
 219                 uint32_t t = context->count[i];
 220
 221                 int j;
 222
 223                 for (j = 0; j < 4; t >>= 8, j++)
 224                         *--fcp = (unsigned char)t}
 225 #else
 226         for (i = 0; i < 8; i++) {
 227                 finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)] >> ((3 - (i & 3)) * 8)) & 255);       /* Endian independent */
 228         }
 229 #endif
 230         c = 0200;
 231         ul_SHA1Update(context, &c, 1);
 232         while ((context->count[0] & 504) != 448) {
 233                 c = 0000;
 234                 ul_SHA1Update(context, &c, 1);
 235         }
 236         ul_SHA1Update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
 237         for (i = 0; i < 20; i++) {
 238                 digest[i] = (unsigned char)
 239                     ((context->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
 240         }
 241         /* Wipe variables */
 242         memset(context, '\0', sizeof(*context));
 243         memset(&finalcount, '\0', sizeof(finalcount));
 244 }
 245
 246 void ul_SHA1(char *hash_out, const char *str, unsigned len)
 247 {
 248         UL_SHA1_CTX ctx;
 249         unsigned int ii;
 250
 251         ul_SHA1Init(&ctx);
 252         for (ii = 0; ii < len; ii += 1)
 253                 ul_SHA1Update(&ctx, (const unsigned char *)str + ii, 1);
 254         ul_SHA1Final((unsigned char *)hash_out, &ctx);
 255         hash_out[20] = '\0';
 256 }