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/*
* Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <libgen.h>
#include <getopt.h> /* for getopt() */
#include <stdarg.h>
#include "buffalo-lib.h"
#define ERR(fmt, args...) do { \
fflush(0); \
fprintf(stderr, "[%s] *** error: " fmt "\n", \
progname, ## args ); \
} while (0)
static char *progname;
static char *ifname;
static char *ofname;
static int do_decrypt;
void usage(int status)
{
FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout;
fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
fprintf(stream,
"\n"
"Options:\n"
" -d decrypt instead of encrypt\n"
" -i <file> read input from the file <file>\n"
" -o <file> write output to the file <file>\n"
" -h show this screen\n"
);
exit(status);
}
static const unsigned char *crypt_key1 = (unsigned char *)
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
static const unsigned char *crypt_key2 = (unsigned char *)
"XYZ0123hijklmnopqABCDEFGHrstuvabcdefgwxyzIJKLMSTUVW456789NOPQR";
static void crypt_header(unsigned char *buf, ssize_t len,
const unsigned char *key1, const unsigned char *key2)
{
ssize_t i;
for (i = 0; i < len; i++) {
unsigned int j;
for (j = 0; key1[j]; j++)
if (buf[i] == key1[j]) {
buf[i] = key2[j];
break;
}
}
}
static int crypt_file(void)
{
unsigned char *buf = NULL;
ssize_t src_len;
int err;
int ret = -1;
src_len = get_file_size(ifname);
if (src_len < 0) {
ERR("unable to get size of '%s'", ifname);
goto out;
}
buf = malloc(src_len);
if (buf == NULL) {
ERR("no memory for the buffer");
goto out;
}
err = read_file_to_buf(ifname, buf, src_len);
if (err) {
ERR("unable to read from file '%s'", ifname);
goto out;
}
if (do_decrypt)
crypt_header(buf, 512, crypt_key2, crypt_key1);
else
crypt_header(buf, 512, crypt_key1, crypt_key2);
err = write_buf_to_file(ofname, buf, src_len);
if (err) {
ERR("unable to write to file '%s'", ofname);
goto out;
}
ret = 0;
out:
free(buf);
return ret;
}
static int check_params(void)
{
int ret = -1;
if (ifname == NULL) {
ERR("no input file specified");
goto out;
}
if (ofname == NULL) {
ERR("no output file specified");
goto out;
}
ret = 0;
out:
return ret;
}
int main(int argc, char *argv[])
{
int res = EXIT_FAILURE;
int err;
progname = basename(argv[0]);
while ( 1 ) {
int c;
c = getopt(argc, argv, "di:o:h");
if (c == -1)
break;
switch (c) {
case 'd':
do_decrypt = 1;
break;
case 'i':
ifname = optarg;
break;
case 'o':
ofname = optarg;
break;
case 'h':
usage(EXIT_SUCCESS);
break;
default:
usage(EXIT_FAILURE);
break;
}
}
err = check_params();
if (err)
goto out;
err = crypt_file();
if (err)
goto out;
res = EXIT_SUCCESS;
out:
return res;
}
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