Dopo aver scritto il codice per l'algoritmo SHA1, nel main ho usato il fileopen per aprire un file chiamato Intero.txt che contiene al suo interno una stringa "abc" che con Sha1 dovrà darmi il suo digest, o almeno DOVREBBE, come mai non funziona?
//Include
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
//Algoritmo SHA1
#undef BIG_ENDIAN_HOST
typedef unsigned int u32;
#if defined(__GNUC__) && defined(__i386__)
static inline u32
rol( u32 x, int n)
{
__asm__("roll %%cl,%0"
:"=r" (x)
:"0" (x),"c" (n));
return x;
}
#else
#define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
#endif
typedef struct {
u32 h0,h1,h2,h3,h4;
u32 nblocks;
unsigned char buf[64];
int count;
} SHA1_CONTEXT;
void
sha1_init( SHA1_CONTEXT *hd )
{
hd->h0 = 0x67452301;
hd->h1 = 0xefcdab89;
hd->h2 = 0x98badcfe;
hd->h3 = 0x10325476;
hd->h4 = 0xc3d2e1f0;
hd->nblocks = 0;
hd->count = 0;
}
/****************
* Transform the message X which consists of 16 32-bit-words
*/
static void
transform( SHA1_CONTEXT *hd, unsigned char *data )
{
u32 a,b,c,d,e,tm;
u32 x[16];
/* get values from the chaining vars */
a = hd->h0;
b = hd->h1;
c = hd->h2;
d = hd->h3;
e = hd->h4;
#ifdef BIG_ENDIAN_HOST
memcpy( x, data, 64 );
#else
{ int i;
unsigned char *p2;
for(i=0, p2=(unsigned char*)x; i < 16; i++, p2 += 4 ) {
p2[3] = *data++;
p2[2] = *data++;
p2[1] = *data++;
p2[0] = *data++;
}
}
#endif
#define K1 0x5A827999L
#define K2 0x6ED9EBA1L
#define K3 0x8F1BBCDCL
#define K4 0xCA62C1D6L
#define F1(x,y,z) ( z ^ ( x & ( y ^ z ) ) )
#define F2(x,y,z) ( x ^ y ^ z )
#define F3(x,y,z) ( ( x & y ) | ( z & ( x | y ) ) )
#define F4(x,y,z) ( x ^ y ^ z )
#define M(i) ( tm = x[i&0x0f] ^ x[(i-14)&0x0f] \
^ x[(i-8)&0x0f] ^ x[(i-3)&0x0f] \
, (x[i&0x0f] = rol(tm,1)) )
#define R(a,b,c,d,e,f,k,m) do { e += rol( a, 5 ) \
+ f( b, c, d ) \
+ k \
+ m; \
b = rol( b, 30 ); \
} while(0)
R( a, b, c, d, e, F1, K1, x[ 0] );
R( e, a, b, c, d, F1, K1, x[ 1] );
R( d, e, a, b, c, F1, K1, x[ 2] );
R( c, d, e, a, b, F1, K1, x[ 3] );
R( b, c, d, e, a, F1, K1, x[ 4] );
R( a, b, c, d, e, F1, K1, x[ 5] );
R( e, a, b, c, d, F1, K1, x[ 6] );
R( d, e, a, b, c, F1, K1, x[ 7] );
R( c, d, e, a, b, F1, K1, x[ 8] );
R( b, c, d, e, a, F1, K1, x[ 9] );
R( a, b, c, d, e, F1, K1, x[10] );
R( e, a, b, c, d, F1, K1, x[11] );
R( d, e, a, b, c, F1, K1, x[12] );
R( c, d, e, a, b, F1, K1, x[13] );
R( b, c, d, e, a, F1, K1, x[14] );
R( a, b, c, d, e, F1, K1, x[15] );
R( e, a, b, c, d, F1, K1, M(16) );
R( d, e, a, b, c, F1, K1, M(17) );
R( c, d, e, a, b, F1, K1, M(18) );
R( b, c, d, e, a, F1, K1, M(19) );
R( a, b, c, d, e, F2, K2, M(20) );
R( e, a, b, c, d, F2, K2, M(21) );
R( d, e, a, b, c, F2, K2, M(22) );
R( c, d, e, a, b, F2, K2, M(23) );
R( b, c, d, e, a, F2, K2, M(24) );
R( a, b, c, d, e, F2, K2, M(25) );
R( e, a, b, c, d, F2, K2, M(26) );
R( d, e, a, b, c, F2, K2, M(27) );
R( c, d, e, a, b, F2, K2, M(28) );
R( b, c, d, e, a, F2, K2, M(29) );
R( a, b, c, d, e, F2, K2, M(30) );
R( e, a, b, c, d, F2, K2, M(31) );
R( d, e, a, b, c, F2, K2, M(32) );
R( c, d, e, a, b, F2, K2, M(33) );
R( b, c, d, e, a, F2, K2, M(34) );
R( a, b, c, d, e, F2, K2, M(35) );
R( e, a, b, c, d, F2, K2, M(36) );
R( d, e, a, b, c, F2, K2, M(37) );
R( c, d, e, a, b, F2, K2, M(38) );
R( b, c, d, e, a, F2, K2, M(39) );
R( a, b, c, d, e, F3, K3, M(40) );
R( e, a, b, c, d, F3, K3, M(41) );
R( d, e, a, b, c, F3, K3, M(42) );
R( c, d, e, a, b, F3, K3, M(43) );
R( b, c, d, e, a, F3, K3, M(44) );
R( a, b, c, d, e, F3, K3, M(45) );
R( e, a, b, c, d, F3, K3, M(46) );
R( d, e, a, b, c, F3, K3, M(47) );
R( c, d, e, a, b, F3, K3, M(48) );
R( b, c, d, e, a, F3, K3, M(49) );
R( a, b, c, d, e, F3, K3, M(50) );
R( e, a, b, c, d, F3, K3, M(51) );
R( d, e, a, b, c, F3, K3, M(52) );
R( c, d, e, a, b, F3, K3, M(53) );
R( b, c, d, e, a, F3, K3, M(54) );
R( a, b, c, d, e, F3, K3, M(55) );
R( e, a, b, c, d, F3, K3, M(56) );
R( d, e, a, b, c, F3, K3, M(57) );
R( c, d, e, a, b, F3, K3, M(58) );
R( b, c, d, e, a, F3, K3, M(59) );
R( a, b, c, d, e, F4, K4, M(60) );
R( e, a, b, c, d, F4, K4, M(61) );
R( d, e, a, b, c, F4, K4, M(62) );
R( c, d, e, a, b, F4, K4, M(63) );
R( b, c, d, e, a, F4, K4, M(64) );
R( a, b, c, d, e, F4, K4, M(65) );
R( e, a, b, c, d, F4, K4, M(66) );
R( d, e, a, b, c, F4, K4, M(67) );
R( c, d, e, a, b, F4, K4, M(68) );
R( b, c, d, e, a, F4, K4, M(69) );
R( a, b, c, d, e, F4, K4, M(70) );
R( e, a, b, c, d, F4, K4, M(71) );
R( d, e, a, b, c, F4, K4, M(72) );
R( c, d, e, a, b, F4, K4, M(73) );
R( b, c, d, e, a, F4, K4, M(74) );
R( a, b, c, d, e, F4, K4, M(75) );
R( e, a, b, c, d, F4, K4, M(76) );
R( d, e, a, b, c, F4, K4, M(77) );
R( c, d, e, a, b, F4, K4, M(78) );
R( b, c, d, e, a, F4, K4, M(79) );
/* Update chaining vars */
hd->h0 += a;
hd->h1 += b;
hd->h2 += c;
hd->h3 += d;
hd->h4 += e;
}
/* Update the message digest with the contents
* of INBUF with length INLEN.
*/
static void
sha1_write( SHA1_CONTEXT *hd, unsigned char *inbuf, size_t inlen)
{
if( hd->count == 64 ) { /* flush the buffer */
transform( hd, hd->buf );
hd->count = 0;
hd->nblocks++;
}
if( !inbuf )
return;
if( hd->count ) {
for( ; inlen && hd->count < 64; inlen-- )
hd->buf[hd->count++] = *inbuf++;
sha1_write( hd, NULL, 0 );
if( !inlen )
return;
}
while( inlen >= 64 ) {
transform( hd, inbuf );
hd->count = 0;
hd->nblocks++;
inlen -= 64;
inbuf += 64;
}
for( ; inlen && hd->count < 64; inlen-- )
hd->buf[hd->count++] = *inbuf++;
}
/* The routine final terminates the computation and
* returns the digest.
* The handle is prepared for a new cycle, but adding bytes to the
* handle will the destroy the returned buffer.
* Returns: 20 bytes representing the digest.
*/
static void
sha1_final(SHA1_CONTEXT *hd)
{
u32 t, msb, lsb;
unsigned char *p;
sha1_write(hd, NULL, 0); /* flush */;
t = hd->nblocks;
/* multiply by 64 to make a byte count */
lsb = t << 6;
msb = t >> 26;
/* add the count */
t = lsb;
if( (lsb += hd->count) < t )
msb++;
/* multiply by 8 to make a bit count */
t = lsb;
lsb <<= 3;
msb <<= 3;
msb |= t >> 29;
if( hd->count < 56 ) { /* enough room */
hd->buf[hd->count++] = 0x80; /* pad */
while( hd->count < 56 )
hd->buf[hd->count++] = 0; /* pad */
}
else { /* need one extra block */
hd->buf[hd->count++] = 0x80; /* pad character */
while( hd->count < 64 )
hd->buf[hd->count++] = 0;
sha1_write(hd, NULL, 0); /* flush */;
memset(hd->buf, 0, 56 ); /* fill next block with zeroes */
}
/* append the 64 bit count */
hd->buf[56] = msb >> 24;
hd->buf[57] = msb >> 16;
hd->buf[58] = msb >> 8;
hd->buf[59] = msb ;
hd->buf[60] = lsb >> 24;
hd->buf[61] = lsb >> 16;
hd->buf[62] = lsb >> 8;
hd->buf[63] = lsb ;
transform( hd, hd->buf );
p = hd->buf;
#ifdef BIG_ENDIAN_HOST
#define X(a) do { *(u32*)p = hd->h##a ; p += 4; } while(0)
#else /* little endian */
#define X(a) do { *p++ = hd->h##a >> 24; *p++ = hd->h##a >> 16; \
*p++ = hd->h##a >> 8; *p++ = hd->h##a; } while(0)
#endif
X(0);
X(1);
X(2);
X(3);
X(4);
#undef X
}
//Main dove richiamo l'algoritmo che legge poi il file txt
int main (int argc, char **argv){
assert (sizeof (u32) == 4);
if (argc < 2)
{
fprintf(stderr, "usage: sha1sum filenames\n");
}
for (argc--, argv++; argc; argv++, argc--)
{
FILE *fp;
char buffer[4096];
size_t n;
SHA1_CONTEXT ctx;
int i;
fp = fopen("Intero.txt", "r");
if (!fp)
{
while(fgets(buffer,4096,fp)) //Ciclerà il file finchè non arriva alla fine
{
//Leggo la riga del file
printf("%s",buffer); //Stampo la riga del file
}
fprintf (stderr, "can't open `%s': %s\n", *argv, strerror (errno));
exit (1);
}
sha1_init (&ctx);
while ( (n = fread (buffer, 1, sizeof buffer, fp)))
sha1_write (&ctx, buffer, n);
if (ferror (fp))
{
fprintf (stderr, "error reading `%s': %s\n", *argv,strerror (errno));
exit (1);
}
sha1_final (&ctx);
fclose (fp);
for (i=0; i < 20; i++)
printf ("%02x", ctx.buf[i]);
printf (" %s\n", *argv);
}
return 0;
}