blob: e4cda431270067d0ecc0137cabe75b8d03d0070a [file] [log] [blame]
/*
* Copyright (C) 2013 STRATO. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "crc32c.h"
void usage(void)
{
printf("usage: btrfs-crc filename\n");
printf(" print out the btrfs crc for \"filename\"\n");
printf("usage: btrfs-crc filename -c crc [-s seed] [-l length]\n");
printf(" brute force search for file names with the given crc\n");
printf(" -s seed the random seed (default: random)\n");
printf(" -l length the length of the file names (default: 10)\n");
exit(1);
}
int main(int argc, char **argv)
{
char c;
unsigned long checksum = 0;
char *str;
char *buf;
int length = 10;
int seed = getpid() ^ getppid();
int loop = 0;
int i;
while ((c = getopt(argc, argv, "l:c:s:h")) != -1) {
switch (c) {
case 'l':
length = atol(optarg);
break;
case 'c':
sscanf(optarg, "%li", &checksum);
loop = 1;
break;
case 's':
seed = atol(optarg);
break;
case 'h':
usage();
case '?':
return 255;
}
}
str = argv[optind];
if (!loop) {
if (optind >= argc) {
fprintf(stderr, "not enough arguments\n");
return 255;
}
printf("%12u - %s\n", crc32c(~1, str, strlen(str)), str);
return 0;
}
buf = malloc(length);
if (!buf)
return -ENOMEM;
srand(seed);
while (1) {
for (i = 0; i < length; i++)
buf[i] = rand() % 94 + 33;
if (crc32c(~1, buf, length) == checksum)
printf("%12lu - %.*s\n", checksum, length, buf);
}
return 0;
}