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     uint32_t block[80];
  50     unsigned int i, a, b, c, d, e;
  51
  52     a = state[0];
  53     b = state[1];
  54     c = state[2];
  55     d = state[3];
  56     e = state[4];
  57 #if CONFIG_SMALL
  58     for(i=0; i<80; i++){
  59         int t;
  60         if(i<16) t= be2me_32(((uint32_t*)buffer)[i]);
  61         else     t= rol(block[i-3]^block[i-8]^block[i-14]^block[i-16],1);
  62         block[i]= t;
  63         t+= e+rol(a,5);
  64         if(i<40){
  65             if(i<20)    t+= ((b&(c^d))^d)    +0x5A827999;
  66             else        t+= ( b^c     ^d)    +0x6ED9EBA1;
  67         }else{
  68             if(i<60)    t+= (((b|c)&d)|(b&c))+0x8F1BBCDC;
  69             else        t+= ( b^c     ^d)    +0xCA62C1D6;
  70         }
  71         e= d;
  72         d= c;
  73         c= rol(b,30);
  74         b= a;
  75         a= t;
  76     }
  77 #else
  78     for(i=0; i<15; i+=5){
  79         R0(a,b,c,d,e,0+i); R0(e,a,b,c,d,1+i); R0(d,e,a,b,c,2+i); R0(c,d,e,a,b,3+i); R0(b,c,d,e,a,4+i);
  80     }
  81     R0(a,b,c,d,e,15); R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
  82     for(i=20; i<40; i+=5){
  83         R2(a,b,c,d,e,0+i); R2(e,a,b,c,d,1+i); R2(d,e,a,b,c,2+i); R2(c,d,e,a,b,3+i); R2(b,c,d,e,a,4+i);
  84     }
  85     for(; i<60; i+=5){
  86         R3(a,b,c,d,e,0+i); R3(e,a,b,c,d,1+i); R3(d,e,a,b,c,2+i); R3(c,d,e,a,b,3+i); R3(b,c,d,e,a,4+i);
  87     }
  88     for(; i<80; i+=5){
  89         R4(a,b,c,d,e,0+i); R4(e,a,b,c,d,1+i); R4(d,e,a,b,c,2+i); R4(c,d,e,a,b,3+i); R4(b,c,d,e,a,4+i);
  90     }
  91 #endif
  92     state[0] += a;
  93     state[1] += b;
  94     state[2] += c;
  95     state[3] += d;
  96     state[4] += e;
  97 }
  98
  99 void av_sha1_init(AVSHA1* ctx){
 100     ctx->state[0] = 0x67452301;
 101     ctx->state[1] = 0xEFCDAB89;
 102     ctx->state[2] = 0x98BADCFE;
 103     ctx->state[3] = 0x10325476;
 104     ctx->state[4] = 0xC3D2E1F0;
 105     ctx->count    = 0;
 106 }
 107
 108 void av_sha1_update(AVSHA1* ctx, const uint8_t* data, unsigned int len){
 109     unsigned int i, j;
 110
 111     j = ctx->count & 63;
 112     ctx->count += len;
 113 #if CONFIG_SMALL
 114     for( i = 0; i < len; i++ ){
 115         ctx->buffer[ j++ ] = data[i];
 116         if( 64 == j ){
 117             transform(ctx->state, ctx->buffer);
 118             j = 0;
 119         }
 120     }
 121 #else
 122     if ((j + len) > 63) {
 123         memcpy(&ctx->buffer[j], data, (i = 64-j));
 124         transform(ctx->state, ctx->buffer);
 125         for ( ; i + 63 < len; i += 64) {
 126             transform(ctx->state, &data[i]);
 127         }
 128         j=0;
 129     }
 130     else i = 0;
 131     memcpy(&ctx->buffer[j], &data[i], len - i);
 132 #endif
 133 }
 134
 135 void av_sha1_final(AVSHA1* ctx, uint8_t digest[20]){
 136     int i;
 137     uint64_t finalcount= be2me_64(ctx->count<<3);
 138
 139     av_sha1_update(ctx, "\200", 1);
 140     while ((ctx->count & 63) != 56) {
 141         av_sha1_update(ctx, "", 1);
 142     }
 143     av_sha1_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
 144     for(i=0; i<5; i++)
 145         ((uint32_t*)digest)[i]= be2me_32(ctx->state[i]);
 146 }
 147
 148 #ifdef TEST
 149 #include <stdio.h>
 150 #undef printf
 151
 152 int main(void){
 153     int i, k;
 154     AVSHA1 ctx;
 155     unsigned char digest[20];
 156
 157     for(k=0; k<3; k++){
 158         av_sha1_init(&ctx);
 159         if(k==0)
 160             av_sha1_update(&ctx, "abc", 3);
 161         else if(k==1)
 162             av_sha1_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
 163         else
 164             for(i=0; i<1000*1000; i++)
 165                 av_sha1_update(&ctx, "a", 1);
 166         av_sha1_final(&ctx, digest);
 167         for (i = 0; i < 20; i++)
 168             printf("%02X", digest[i]);
 169         putchar('\n');
 170     }
 171     //test vectors (from FIPS PUB 180-1)
 172     printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
 173            "84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
 174            "34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
 175
 176     return 0;
 177 }
 178 #endif