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#include "../lib/lib.h"
int main(int arc, char **argv)
{
// detect AEC in ECB mode, do NOT break it
int number_blocks, i, j, k, read = 0;
size_t len = 0;
int max_hits = 0, hits = 0, line_number= 0, aes_ecb_line = 0;
char *line_hex = NULL;
// read file
FILE *f = fopen("8.txt", "r");
if (f == NULL) {
perror("failed to open 8.txt");
exit(1);
}
while( (read = getline(&line_hex, &len, f)) != -1) {
// line is hex encoded
char *line = malloc(read/2+1);
decode_hex_string(line_hex, line);
number_blocks = read / 2 / 16;
// count 16 byte blocks which are equal
for(i=0;i<number_blocks;i++) {
for(j=1;j<number_blocks;j++) {
for(k=0;k<16;k++) {
if(line[i*16+k] != line[j*16+k])
break;
if ( k == 15)
hits++;
}
}
}
printf("line: %i, hits: %i\n", line_number, hits);
if (hits > max_hits) {
max_hits = hits;
aes_ecb_line = line_number;
}
line_number++;
hits = 0;
free(line_hex);
free(line);
// set line and len to null
line = NULL;
len = 0;
}
printf("found AES-128-ECB at line: %i\n with %i hits", aes_ecb_line, max_hits);
return 0;
}
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