/*
* Copyright (C) 2007 Michael Niedermayer <michaelni@gmx.at>
* based on public domain SHA-1 code by Steve Reid <steve@edmweb.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "common.h"
#include "bswap.h"
#include "sha1.h"
typedef struct AVSHA1 {
uint64_t count;
uint8_t buffer[64];
uint32_t state[5];
} AVSHA1;
const int av_sha1_size = sizeof(AVSHA1);
#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#define blk0(i) (block[i] = be2me_32(((const uint32_t*)buffer)[i]))
#define blk(i) (block[i] = rol(block[i-3]^block[i-8]^block[i-14]^block[i-16],1))
#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y) +blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y) +blk (i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=( w^x ^y) +blk (i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk (i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=( w^x ^y) +blk (i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
/* Hash a single 512-bit block. This is the core of the algorithm. */
static void transform(uint32_t state[5], const uint8_t buffer[64]){
uint32_t block[80];
unsigned int i, a, b, c, d, e;
a = state[0];
b = state[1];
c = state[2];
d = state[3];
e = state[4];
#if CONFIG_SMALL
for(i=0; i<80; i++){
int t;
if(i<16) t= be2me_32(((uint32_t*)buffer)[i]);
else t= rol(block[i-3]^block[i-8]^block[i-14]^block[i-16],1);
block[i]= t;
t+= e+rol(a,5);
if(i<40){
if(i<20) t+= ((b&(c^d))^d) +0x5A827999;
else t+= ( b^c ^d) +0x6ED9EBA1;
}else{
if(i<60) t+= (((b|c)&d)|(b&c))+0x8F1BBCDC;
else t+= ( b^c ^d) +0xCA62C1D6;
}
e= d;
d= c;
c= rol(b,30);
b= a;
a= t;
}
#else
for(i=0; i<15; i+=5){
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);
}
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);
for(i=20; i<40; i+=5){
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);
}
for(; i<60; i+=5){
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);
}
for(; i<80; i+=5){
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);
}
#endif
state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;
state[4] += e;
}
void av_sha1_init(AVSHA1* ctx){
ctx->state[0] = 0x67452301;
ctx->state[1] = 0xEFCDAB89;
ctx->state[2] = 0x98BADCFE;
ctx->state[3] = 0x10325476;
ctx->state[4] = 0xC3D2E1F0;
ctx->count = 0;
}
void av_sha1_update(AVSHA1* ctx, const uint8_t* data, unsigned int len){
unsigned int i, j;
j = ctx->count & 63;
ctx->count += len;
#if CONFIG_SMALL
for( i = 0; i < len; i++ ){
ctx->buffer[ j++ ] = data[i];
if( 64 == j ){
transform(ctx->state, ctx->buffer);
j = 0;
}
}
#else
if ((j + len) > 63) {
memcpy(&ctx->buffer[j], data, (i = 64-j));
transform(ctx->state, ctx->buffer);
for ( ; i + 63 < len; i += 64) {
transform(ctx->state, &data[i]);
}
j=0;
}
else i = 0;
memcpy(&ctx->buffer[j], &data[i], len - i);
#endif
}
void av_sha1_final(AVSHA1* ctx, uint8_t digest[20]){
int i;
uint64_t finalcount= be2me_64(ctx->count<<3);
av_sha1_update(ctx, "\200", 1);
while ((ctx->count & 63) != 56) {
av_sha1_update(ctx, "", 1);
}
av_sha1_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
for(i=0; i<5; i++)
((uint32_t*)digest)[i]= be2me_32(ctx->state[i]);
}
#ifdef TEST
#include <stdio.h>
#undef printf
int main(void){
int i, k;
AVSHA1 ctx;
unsigned char digest[20];
for(k=0; k<3; k++){
av_sha1_init(&ctx);
if(k==0)
av_sha1_update(&ctx, "abc", 3);
else if(k==1)
av_sha1_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
else
for(i=0; i<1000*1000; i++)
av_sha1_update(&ctx, "a", 1);
av_sha1_final(&ctx, digest);
for (i = 0; i < 20; i++)
printf("%02X", digest[i]);
putchar('\n');
}
//test vectors (from FIPS PUB 180-1)
printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
"84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
"34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
return 0;
}
#endif