tools/firmware-utils/src/buffalo-tftp.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
   4  */
   5
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <stdint.h>
   9 #include <string.h>
  10 #include <libgen.h>
  11 #include <getopt.h>     /* for getopt() */
  12 #include <stdarg.h>
  13
  14 #include "buffalo-lib.h"
  15
  16 #define ERR(fmt, args...) do { \
  17         fflush(0); \
  18         fprintf(stderr, "[%s] *** error: " fmt "\n", \
  19                         progname, ## args ); \
  20 } while (0)
  21
  22 static char *progname;
  23 static char *ifname;
  24 static char *ofname;
  25 static int do_decrypt;
  26
  27 void usage(int status)
  28 {
  29         FILE *stream = (status != EXIT_SUCCESS) ? stderr : stdout;
  30
  31         fprintf(stream, "Usage: %s [OPTIONS...]\n", progname);
  32         fprintf(stream,
  33 "\n"
  34 "Options:\n"
  35 "  -d              decrypt instead of encrypt\n"
  36 "  -i <file>       read input from the file <file>\n"
  37 "  -o <file>       write output to the file <file>\n"
  38 "  -h              show this screen\n"
  39         );
  40
  41         exit(status);
  42 }
  43
  44 static const unsigned char *crypt_key1 = (unsigned char *)
  45         "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
  46 static const unsigned char *crypt_key2 = (unsigned char *)
  47         "XYZ0123hijklmnopqABCDEFGHrstuvabcdefgwxyzIJKLMSTUVW456789NOPQR";
  48
  49 static void crypt_header(unsigned char *buf, ssize_t len,
  50                          const unsigned char *key1, const unsigned char *key2)
  51 {
  52         ssize_t i;
  53
  54         for (i = 0; i < len; i++) {
  55                 unsigned int j;
  56
  57                 for (j = 0; key1[j]; j++)
  58                         if (buf[i] == key1[j]) {
  59                                 buf[i] = key2[j];
  60                                 break;
  61                         }
  62         }
  63 }
  64
  65 static int crypt_file(void)
  66 {
  67         unsigned char *buf = NULL;
  68         ssize_t src_len;
  69         int err;
  70         int ret = -1;
  71
  72         src_len = get_file_size(ifname);
  73         if (src_len < 0) {
  74                 ERR("unable to get size of '%s'", ifname);
  75                 goto out;
  76         }
  77
  78         buf = malloc(src_len);
  79         if (buf == NULL) {
  80                 ERR("no memory for the buffer");
  81                 goto out;
  82         }
  83
  84         err = read_file_to_buf(ifname, buf, src_len);
  85         if (err) {
  86                 ERR("unable to read from file '%s'", ifname);
  87                 goto out;
  88         }
  89
  90         if (do_decrypt)
  91                 crypt_header(buf, 512, crypt_key2, crypt_key1);
  92         else
  93                 crypt_header(buf, 512, crypt_key1, crypt_key2);
  94
  95         err = write_buf_to_file(ofname, buf, src_len);
  96         if (err) {
  97                 ERR("unable to write to file '%s'", ofname);
  98                 goto out;
  99         }
 100
 101         ret = 0;
 102
 103 out:
 104         free(buf);
 105         return ret;
 106 }
 107
 108 static int check_params(void)
 109 {
 110         int ret = -1;
 111
 112         if (ifname == NULL) {
 113                 ERR("no input file specified");
 114                 goto out;
 115         }
 116
 117         if (ofname == NULL) {
 118                 ERR("no output file specified");
 119                 goto out;
 120         }
 121
 122         ret = 0;
 123
 124 out:
 125         return ret;
 126 }
 127
 128 int main(int argc, char *argv[])
 129 {
 130         int res = EXIT_FAILURE;
 131         int err;
 132
 133         progname = basename(argv[0]);
 134
 135         while ( 1 ) {
 136                 int c;
 137
 138                 c = getopt(argc, argv, "di:o:h");
 139                 if (c == -1)
 140                         break;
 141
 142                 switch (c) {
 143                 case 'd':
 144                         do_decrypt = 1;
 145                         break;
 146                 case 'i':
 147                         ifname = optarg;
 148                         break;
 149                 case 'o':
 150                         ofname = optarg;
 151                         break;
 152                 case 'h':
 153                         usage(EXIT_SUCCESS);
 154                         break;
 155                 default:
 156                         usage(EXIT_FAILURE);
 157                         break;
 158                 }
 159         }
 160
 161         err = check_params();
 162         if (err)
 163                 goto out;
 164
 165         err = crypt_file();
 166         if (err)
 167                 goto out;
 168
 169         res = EXIT_SUCCESS;
 170
 171 out:
 172         return res;
 173 }