sha256.cpp

//
//  sha256.cpp
//  Jako
//
//  Created by John Zakharov on 06.08.16.
//  Copyright © 2016 Outlaw Studio. All rights reserved.
//

#include "sha256.hpp"

void sha256_starts( sha256_context *ctx ){
    ctx->total[0] = 0;
    ctx->total[1] = 0;
    
    ctx->state[0] = 0x6A09E667;
    ctx->state[1] = 0xBB67AE85;
    ctx->state[2] = 0x3C6EF372;
    ctx->state[3] = 0xA54FF53A;
    ctx->state[4] = 0x510E527F;
    ctx->state[5] = 0x9B05688C;
    ctx->state[6] = 0x1F83D9AB;
    ctx->state[7] = 0x5BE0CD19;
}

void sha256_process( sha256_context *ctx, uint8 data[64] ){
    uint32 temp1, temp2, W[64];
    uint32 A, B, C, D, E, F, G, H;
    
    GET_UINT32( W[0],  data,  0 );
    GET_UINT32( W[1],  data,  4 );
    GET_UINT32( W[2],  data,  8 );
    GET_UINT32( W[3],  data, 12 );
    GET_UINT32( W[4],  data, 16 );
    GET_UINT32( W[5],  data, 20 );
    GET_UINT32( W[6],  data, 24 );
    GET_UINT32( W[7],  data, 28 );
    GET_UINT32( W[8],  data, 32 );
    GET_UINT32( W[9],  data, 36 );
    GET_UINT32( W[10], data, 40 );
    GET_UINT32( W[11], data, 44 );
    GET_UINT32( W[12], data, 48 );
    GET_UINT32( W[13], data, 52 );
    GET_UINT32( W[14], data, 56 );
    GET_UINT32( W[15], data, 60 );
    
#define  SHR(x,n) ((x & 0xFFFFFFFF) >> n)
#define ROTR(x,n) (SHR(x,n) | (x << (32 - n)))
    
#define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^  SHR(x, 3))
#define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^  SHR(x,10))
    
#define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
#define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))
    
#define F0(x,y,z) ((x & y) | (z & (x | y)))
#define F1(x,y,z) (z ^ (x & (y ^ z)))
    
#define R(t)                                    \
(                                               \
W[t] = S1(W[t -  2]) + W[t -  7] +          \
S0(W[t - 15]) + W[t - 16]            \
)
    
#define P(a,b,c,d,e,f,g,h,x,K)                  \
{                                               \
temp1 = h + S3(e) + F1(e,f,g) + K + x;      \
temp2 = S2(a) + F0(a,b,c);                  \
d += temp1; h = temp1 + temp2;              \
}
    
    A = ctx->state[0];
    B = ctx->state[1];
    C = ctx->state[2];
    D = ctx->state[3];
    E = ctx->state[4];
    F = ctx->state[5];
    G = ctx->state[6];
    H = ctx->state[7];
    
    P( A, B, C, D, E, F, G, H, W[ 0], 0x428A2F98 );
    P( H, A, B, C, D, E, F, G, W[ 1], 0x71374491 );
    P( G, H, A, B, C, D, E, F, W[ 2], 0xB5C0FBCF );
    P( F, G, H, A, B, C, D, E, W[ 3], 0xE9B5DBA5 );
    P( E, F, G, H, A, B, C, D, W[ 4], 0x3956C25B );
    P( D, E, F, G, H, A, B, C, W[ 5], 0x59F111F1 );
    P( C, D, E, F, G, H, A, B, W[ 6], 0x923F82A4 );
    P( B, C, D, E, F, G, H, A, W[ 7], 0xAB1C5ED5 );
    P( A, B, C, D, E, F, G, H, W[ 8], 0xD807AA98 );
    P( H, A, B, C, D, E, F, G, W[ 9], 0x12835B01 );
    P( G, H, A, B, C, D, E, F, W[10], 0x243185BE );
    P( F, G, H, A, B, C, D, E, W[11], 0x550C7DC3 );
    P( E, F, G, H, A, B, C, D, W[12], 0x72BE5D74 );
    P( D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE );
    P( C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7 );
    P( B, C, D, E, F, G, H, A, W[15], 0xC19BF174 );
    P( A, B, C, D, E, F, G, H, R(16), 0xE49B69C1 );
    P( H, A, B, C, D, E, F, G, R(17), 0xEFBE4786 );
    P( G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6 );
    P( F, G, H, A, B, C, D, E, R(19), 0x240CA1CC );
    P( E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F );
    P( D, E, F, G, H, A, B, C, R(21), 0x4A7484AA );
    P( C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC );
    P( B, C, D, E, F, G, H, A, R(23), 0x76F988DA );
    P( A, B, C, D, E, F, G, H, R(24), 0x983E5152 );
    P( H, A, B, C, D, E, F, G, R(25), 0xA831C66D );
    P( G, H, A, B, C, D, E, F, R(26), 0xB00327C8 );
    P( F, G, H, A, B, C, D, E, R(27), 0xBF597FC7 );
    P( E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3 );
    P( D, E, F, G, H, A, B, C, R(29), 0xD5A79147 );
    P( C, D, E, F, G, H, A, B, R(30), 0x06CA6351 );
    P( B, C, D, E, F, G, H, A, R(31), 0x14292967 );
    P( A, B, C, D, E, F, G, H, R(32), 0x27B70A85 );
    P( H, A, B, C, D, E, F, G, R(33), 0x2E1B2138 );
    P( G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC );
    P( F, G, H, A, B, C, D, E, R(35), 0x53380D13 );
    P( E, F, G, H, A, B, C, D, R(36), 0x650A7354 );
    P( D, E, F, G, H, A, B, C, R(37), 0x766A0ABB );
    P( C, D, E, F, G, H, A, B, R(38), 0x81C2C92E );
    P( B, C, D, E, F, G, H, A, R(39), 0x92722C85 );
    P( A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1 );
    P( H, A, B, C, D, E, F, G, R(41), 0xA81A664B );
    P( G, H, A, B, C, D, E, F, R(42), 0xC24B8B70 );
    P( F, G, H, A, B, C, D, E, R(43), 0xC76C51A3 );
    P( E, F, G, H, A, B, C, D, R(44), 0xD192E819 );
    P( D, E, F, G, H, A, B, C, R(45), 0xD6990624 );
    P( C, D, E, F, G, H, A, B, R(46), 0xF40E3585 );
    P( B, C, D, E, F, G, H, A, R(47), 0x106AA070 );
    P( A, B, C, D, E, F, G, H, R(48), 0x19A4C116 );
    P( H, A, B, C, D, E, F, G, R(49), 0x1E376C08 );
    P( G, H, A, B, C, D, E, F, R(50), 0x2748774C );
    P( F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5 );
    P( E, F, G, H, A, B, C, D, R(52), 0x391C0CB3 );
    P( D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A );
    P( C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F );
    P( B, C, D, E, F, G, H, A, R(55), 0x682E6FF3 );
    P( A, B, C, D, E, F, G, H, R(56), 0x748F82EE );
    P( H, A, B, C, D, E, F, G, R(57), 0x78A5636F );
    P( G, H, A, B, C, D, E, F, R(58), 0x84C87814 );
    P( F, G, H, A, B, C, D, E, R(59), 0x8CC70208 );
    P( E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA );
    P( D, E, F, G, H, A, B, C, R(61), 0xA4506CEB );
    P( C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7 );
    P( B, C, D, E, F, G, H, A, R(63), 0xC67178F2 );
    
    ctx->state[0] += A;
    ctx->state[1] += B;
    ctx->state[2] += C;
    ctx->state[3] += D;
    ctx->state[4] += E;
    ctx->state[5] += F;
    ctx->state[6] += G;
    ctx->state[7] += H;
}

void sha256_update( sha256_context *ctx, uint8 *input, uint32 length ){
    uint32 left, fill;
    
    if( ! length ) return;
    
    left = ctx->total[0] & 0x3F;
    fill = 64 - left;
    
    ctx->total[0] += length;
    ctx->total[0] &= 0xFFFFFFFF;
    
    if( ctx->total[0] < length )
        ctx->total[1]++;
    
    if( left && length >= fill )
    {
        memcpy( (void *) (ctx->buffer + left),
               (void *) input, fill );
        sha256_process( ctx, ctx->buffer );
        length -= fill;
        input  += fill;
        left = 0;
    }
    
    while( length >= 64 )
    {
        sha256_process( ctx, input );
        length -= 64;
        input  += 64;
    }
    
    if( length )
    {
        memcpy( (void *) (ctx->buffer + left),
               (void *) input, length );
    }
}

void sha256_finish( sha256_context *ctx, uint8 digest[32] ){
    uint32 last, padn;
    uint32 high, low;
    uint8 msglen[8];
    
    high = ( ctx->total[0] >> 29 )
    | ( ctx->total[1] <<  3 );
    low  = ( ctx->total[0] <<  3 );
    
    PUT_UINT32( high, msglen, 0 );
    PUT_UINT32( low,  msglen, 4 );
    
    last = ctx->total[0] & 0x3F;
    padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );
    
    sha256_update( ctx, sha256_padding, padn );
    sha256_update( ctx, msglen, 8 );
    
    PUT_UINT32( ctx->state[0], digest,  0 );
    PUT_UINT32( ctx->state[1], digest,  4 );
    PUT_UINT32( ctx->state[2], digest,  8 );
    PUT_UINT32( ctx->state[3], digest, 12 );
    PUT_UINT32( ctx->state[4], digest, 16 );
    PUT_UINT32( ctx->state[5], digest, 20 );
    PUT_UINT32( ctx->state[6], digest, 24 );
    PUT_UINT32( ctx->state[7], digest, 28 );
}

void sha256_print(unsigned char *digest,size_t len){
    size_t i;
    for(i=0;i<len;++i){
        unsigned char c;
        
        c=digest[i]&240;
        c=c>>4;
        printf("%x",c);
        
        c=digest[i]&15;
        printf("%x",c);
        
    }
    printf("\n");
}

void sha256(unsigned char *data,size_t len,unsigned char output[32]){
    sha256_context ctx;
    sha256_starts(&ctx);
    sha256_update(&ctx,(unsigned char*)data,len);
    sha256_finish(&ctx,output);
}

int sha256_file(const char *filename,uint8 digest[32]){
    int res=0;
    sha256_context ctx;
    sha256_starts(&ctx);
    FILE *file=fopen(filename,"rb");
    if(file){
        size_t bytesRead=0,portionSize=2048;
        char *data=new char[portionSize];
        if(data){
            bool endOfFile=false;
            do{
                bytesRead=fread(data,1,portionSize,file);
                if(bytesRead<portionSize){
                    endOfFile=true;
                }
                if(bytesRead){
                    sha256_update(&ctx,(unsigned char*)data,bytesRead);
                }
            }while(!endOfFile);
            sha256_finish(&ctx,digest);
            delete[] data;
        }else{
            printf("can not allocate %ld bytes\n",long(portionSize));
        }
    }else{
        res=1;
    }
    return res;
}