libavutil/sha1.c

   1 /*
   2  * Copyright (C) 2007 Michael Niedermayer <michaelni@gmx.at>
   3  * based on public domain SHA-1 code by Steve Reid <steve@edmweb.com>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "common.h"
  23 #include "bswap.h"
  24 #include "sha1.h"
  25
  26 typedef struct AVSHA1 {
  27     uint64_t count;
  28     uint8_t buffer[64];
  29     uint32_t state[5];
  30 } AVSHA1;
  31
  32 const int av_sha1_size = sizeof(AVSHA1);
  33
  34 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  35
  36 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  37 #define blk0(i) (block[i] = be2me_32(((const uint32_t*)buffer)[i]))
  38 #define blk(i)  (block[i] = rol(block[i-3] ^ block[i-8] ^ block[i-14] ^ block[i-16], 1))
  39
  40 #define R0(v,w,x,y,z,i) z += ((w&(x^y))^y)     + blk0(i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
  41 #define R1(v,w,x,y,z,i) z += ((w&(x^y))^y)     + blk (i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
  42 #define R2(v,w,x,y,z,i) z += ( w^x     ^y)     + blk (i) + 0x6ED9EBA1 + rol(v, 5); w = rol(w, 30);
  43 #define R3(v,w,x,y,z,i) z += (((w|x)&y)|(w&x)) + blk (i) + 0x8F1BBCDC + rol(v, 5); w = rol(w, 30);
  44 #define R4(v,w,x,y,z,i) z += ( w^x     ^y)     + blk (i) + 0xCA62C1D6 + rol(v, 5); w = rol(w, 30);
  45
  46 /* Hash a single 512-bit block. This is the core of the algorithm. */
  47
  48 static void transform(uint32_t state[5], const uint8_t buffer[64])
  49 {
  50     uint32_t block[80];
  51     unsigned int i, a, b, c, d, e;
  52
  53     a = state[0];
  54     b = state[1];
  55     c = state[2];
  56     d = state[3];
  57     e = state[4];
  58 #if CONFIG_SMALL
  59     for (i = 0; i < 80; i++) {
  60         int t;
  61         if (i < 16)
  62             t = be2me_32(((uint32_t*)buffer)[i]);
  63         else
  64             t = rol(block[i-3] ^ block[i-8] ^ block[i-14] ^ block[i-16], 1);
  65         block[i] = t;
  66         t += e + rol(a, 5);
  67         if (i < 40) {
  68             if (i < 20)
  69                 t += ((b&(c^d))^d)     + 0x5A827999;
  70             else
  71                 t += ( b^c     ^d)     + 0x6ED9EBA1;
  72         } else {
  73             if (i < 60)
  74                 t += (((b|c)&d)|(b&c)) + 0x8F1BBCDC;
  75             else
  76                 t += ( b^c     ^d)     + 0xCA62C1D6;
  77         }
  78         e = d;
  79         d = c;
  80         c = rol(b, 30);
  81         b = a;
  82         a = t;
  83     }
  84 #else
  85     for (i = 0; i < 15; i += 5) {
  86         R0(a, b, c, d, e, 0 + i);
  87         R0(e, a, b, c, d, 1 + i);
  88         R0(d, e, a, b, c, 2 + i);
  89         R0(c, d, e, a, b, 3 + i);
  90         R0(b, c, d, e, a, 4 + i);
  91     }
  92     R0(a, b, c, d, e, 15);
  93     R1(e, a, b, c, d, 16);
  94     R1(d, e, a, b, c, 17);
  95     R1(c, d, e, a, b, 18);
  96     R1(b, c, d, e, a, 19);
  97     for (i = 20; i < 40; i += 5) {
  98         R2(a, b, c, d, e, 0 + i);
  99         R2(e, a, b, c, d, 1 + i);
 100         R2(d, e, a, b, c, 2 + i);
 101         R2(c, d, e, a, b, 3 + i);
 102         R2(b, c, d, e, a, 4 + i);
 103     }
 104     for (; i < 60; i += 5) {
 105         R3(a, b, c, d, e, 0 + i);
 106         R3(e, a, b, c, d, 1 + i);
 107         R3(d, e, a, b, c, 2 + i);
 108         R3(c, d, e, a, b, 3 + i);
 109         R3(b, c, d, e, a, 4 + i);
 110     }
 111     for (; i < 80; i += 5) {
 112         R4(a, b, c, d, e, 0 + i);
 113         R4(e, a, b, c, d, 1 + i);
 114         R4(d, e, a, b, c, 2 + i);
 115         R4(c, d, e, a, b, 3 + i);
 116         R4(b, c, d, e, a, 4 + i);
 117     }
 118 #endif
 119     state[0] += a;
 120     state[1] += b;
 121     state[2] += c;
 122     state[3] += d;
 123     state[4] += e;
 124 }
 125
 126 void av_sha1_init(AVSHA1* ctx)
 127 {
 128     ctx->state[0] = 0x67452301;
 129     ctx->state[1] = 0xEFCDAB89;
 130     ctx->state[2] = 0x98BADCFE;
 131     ctx->state[3] = 0x10325476;
 132     ctx->state[4] = 0xC3D2E1F0;
 133     ctx->count    = 0;
 134 }
 135
 136 void av_sha1_update(AVSHA1* ctx, const uint8_t* data, unsigned int len)
 137 {
 138     unsigned int i, j;
 139
 140     j = ctx->count & 63;
 141     ctx->count += len;
 142 #if CONFIG_SMALL
 143     for (i = 0; i < len; i++) {
 144         ctx->buffer[j++] = data[i];
 145         if (64 == j) {
 146             transform(ctx->state, ctx->buffer);
 147             j = 0;
 148         }
 149     }
 150 #else
 151     if ((j + len) > 63) {
 152         memcpy(&ctx->buffer[j], data, (i = 64 - j));
 153         transform(ctx->state, ctx->buffer);
 154         for (; i + 63 < len; i += 64)
 155             transform(ctx->state, &data[i]);
 156         j = 0;
 157     } else
 158         i = 0;
 159     memcpy(&ctx->buffer[j], &data[i], len - i);
 160 #endif
 161 }
 162
 163 void av_sha1_final(AVSHA1* ctx, uint8_t digest[20])
 164 {
 165     int i;
 166     uint64_t finalcount = be2me_64(ctx->count << 3);
 167
 168     av_sha1_update(ctx, "\200", 1);
 169     while ((ctx->count & 63) != 56)
 170         av_sha1_update(ctx, "", 1);
 171     av_sha1_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
 172     for (i = 0; i < 5; i++)
 173         ((uint32_t*)digest)[i] = be2me_32(ctx->state[i]);
 174 }
 175
 176 #ifdef TEST
 177 #include <stdio.h>
 178 #undef printf
 179
 180 int main(void)
 181 {
 182     int i, k;
 183     AVSHA1 ctx;
 184     unsigned char digest[20];
 185
 186     for (k = 0; k < 3; k++) {
 187         av_sha1_init(&ctx);
 188         if (k == 0)
 189             av_sha1_update(&ctx, "abc", 3);
 190         else if (k == 1)
 191             av_sha1_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
 192         else
 193             for (i = 0; i < 1000 * 1000; i++)
 194                 av_sha1_update(&ctx, "a", 1);
 195         av_sha1_final(&ctx, digest);
 196         for (i = 0; i < 20; i++)
 197             printf("%02X", digest[i]);
 198         putchar('\n');
 199     }
 200     //test vectors (from FIPS PUB 180-1)
 201     printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
 202            "84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
 203            "34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
 204
 205     return 0;
 206 }
 207 #endif