jffs2reset.c

   1 /*
   2  * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <sys/mount.h>
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17
  18 #include <fcntl.h>
  19 #include <dirent.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24
  25 #include "libfstools/libfstools.h"
  26 #include "libfstools/volume.h"
  27
  28 static int
  29 handle_rmdir(const char *dir)
  30 {
  31         struct stat s;
  32         struct dirent **namelist;
  33         int n;
  34
  35         n = scandir(dir, &namelist, NULL, NULL);
  36
  37         if (n < 1)
  38                 return -1;
  39
  40         while (n--) {
  41                 char file[256];
  42
  43                 snprintf(file, sizeof(file), "%s%s", dir, namelist[n]->d_name);
  44                 if (!lstat(file, &s) && !S_ISDIR(s.st_mode))
  45                         unlink(file);
  46                 free(namelist[n]);
  47         }
  48         free(namelist);
  49
  50         rmdir(dir);
  51
  52         return 0;
  53 }
  54
  55 static int
  56 ask_user(int argc, char **argv)
  57 {
  58         if ((argc < 2) || strcmp(argv[1], "-y")) {
  59                 fprintf(stderr, "This will erase all settings and remove any installed packages. Are you sure? [N/y]\n");
  60                 if (getchar() != 'y')
  61                         return -1;
  62         }
  63         return 0;
  64
  65 }
  66
  67 static int
  68 jffs2_reset(int argc, char **argv)
  69 {
  70         struct volume *v;
  71         char *mp;
  72
  73         if (ask_user(argc, argv))
  74                 return -1;
  75
  76         if (find_filesystem("overlay")) {
  77                 fprintf(stderr, "overlayfs not found\n");
  78                 return -1;
  79         }
  80
  81         v = volume_find("rootfs_data");
  82         if (!v) {
  83                 fprintf(stderr, "no rootfs_data was found\n");
  84                 return -1;
  85         }
  86
  87         mp = find_mount_point(v->blk, 1);
  88         if (mp) {
  89                 fprintf(stderr, "%s is mounted as %s, only erasing files\n", v->blk, mp);
  90                 foreachdir(mp, handle_rmdir);
  91                 mount(mp, "/", NULL, MS_REMOUNT, 0);
  92         } else {
  93                 fprintf(stderr, "%s is not mounted, erasing it\n", v->blk);
  94                 volume_erase_all(v);
  95         }
  96
  97         return 0;
  98 }
  99
 100 static int
 101 jffs2_mark(int argc, char **argv)
 102 {
 103         __u32 deadc0de = __cpu_to_be32(0xdeadc0de);
 104         struct volume *v;
 105         size_t sz;
 106         int fd;
 107
 108         if (ask_user(argc, argv))
 109                 return -1;
 110
 111         v = volume_find("rootfs_data");
 112         if (!v) {
 113                 fprintf(stderr, "no rootfs_data was found\n");
 114                 return -1;
 115         }
 116
 117         fd = open(v->blk, O_WRONLY);
 118         fprintf(stderr, "%s - marking with deadc0de\n", v->blk);
 119         if (!fd) {
 120                 fprintf(stderr, "opening %s failed\n", v->blk);
 121                 return -1;
 122         }
 123
 124         sz = write(fd, &deadc0de, sizeof(deadc0de));
 125         close(fd);
 126
 127         if (sz != 4) {
 128                 fprintf(stderr, "writing %s failed: %s\n", v->blk, strerror(errno));
 129                 return -1;
 130         }
 131
 132         return 0;
 133 }
 134
 135 int main(int argc, char **argv)
 136 {
 137         if (!strcmp(*argv, "jffs2mark"))
 138                 return jffs2_mark(argc, argv);
 139         return jffs2_reset(argc, argv);
 140 }