target/linux/ar7/src/adam2patcher.c

   1 /*
   2  * patcher.c - ADAM2 patcher for Netgear DG834 (and compatible)
   3  *
   4  * Copyright (C) 2006 Felix Fietkau
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <stddef.h>
  20 #include <unistd.h>
  21 #include <fcntl.h>
  22 #include <stdint.h>
  23 #include <sys/mman.h>
  24 #include <sys/stat.h>
  25 #include <string.h>
  26
  27 #include <sys/ioctl.h>
  28
  29 int main(int argc, char **argv)
  30 {
  31         int fd;
  32         char *ptr;
  33         uint32_t *i;
  34
  35         if (argc != 2) {
  36                 fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
  37                 exit(1);
  38         }
  39
  40         if (((fd = open(argv[1], O_RDWR)) < 0)
  41                         || ((ptr = mmap(0, 128 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == (void *) (-1))) {
  42                 fprintf(stderr, "Can't open file\n");
  43                 exit(1);
  44         }
  45
  46         i = (uint32_t *) &ptr[0x3944];
  47         if (*i == 0x0c000944) {
  48                 fprintf(stderr, "Unpatched ADAM2 detected. Patching... ");
  49                 *i = 0x00000000;
  50                 msync(i, sizeof(*i), MS_SYNC|MS_INVALIDATE);
  51                 fprintf(stderr, "done!\n");
  52         } else if (*i == 0x00000000) {
  53                 fprintf(stderr, "Patched ADAM2 detected.\n");
  54         } else {
  55                 fprintf(stderr, "Unknown ADAM2 detected. Can't patch!\n");
  56         }
  57
  58         close(fd);
  59 }