--- /dev/null
+/*
+ * 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;
+ ssize_t crypt_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;
+ }
+
+ crypt_len = (src_len > 512) ? 512 : src_len;
+ 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;
+}