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 <libubox/ulog.h>
  19
  20 #include <fcntl.h>
  21 #include <dirent.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26
  27 #include "libfstools/libfstools.h"
  28 #include "libfstools/volume.h"
  29
  30 static int
  31 ask_user(int argc, char **argv)
  32 {
  33         if ((argc < 2) || strcmp(argv[1], "-y")) {
  34                 ULOG_WARN("This will erase all settings and remove any installed packages. Are you sure? [N/y]\n");
  35                 if (getchar() != 'y')
  36                         return -1;
  37         }
  38         return 0;
  39
  40 }
  41
  42 static int jffs2_reset(struct volume *v)
  43 {
  44         char *mp;
  45
  46         mp = find_mount_point(v->blk, 1);
  47         if (mp) {
  48                 ULOG_INFO("%s is mounted as %s, only erasing files\n", v->blk, mp);
  49                 fs_state_set("/overlay", FS_STATE_PENDING);
  50                 overlay_delete(mp, false);
  51                 mount(mp, "/", NULL, MS_REMOUNT, 0);
  52         } else {
  53                 ULOG_INFO("%s is not mounted, erasing it\n", v->blk);
  54                 volume_erase_all(v);
  55         }
  56
  57         return 0;
  58 }
  59
  60 static int jffs2_mark(struct volume *v)
  61 {
  62         __u32 deadc0de = __cpu_to_be32(0xdeadc0de);
  63         size_t sz;
  64         int fd;
  65
  66         fd = open(v->blk, O_WRONLY);
  67         ULOG_INFO("%s - marking with deadc0de\n", v->blk);
  68         if (!fd) {
  69                 ULOG_ERR("opening %s failed\n", v->blk);
  70                 return -1;
  71         }
  72
  73         sz = write(fd, &deadc0de, sizeof(deadc0de));
  74         close(fd);
  75
  76         if (sz != 4) {
  77                 ULOG_ERR("writing %s failed: %s\n", v->blk, strerror(errno));
  78                 return -1;
  79         }
  80
  81         return 0;
  82 }
  83
  84 int main(int argc, char **argv)
  85 {
  86         struct volume *v;
  87
  88         if (ask_user(argc, argv))
  89                 return -1;
  90
  91         /*
  92          * TODO: Currently this only checks if kernel supports OverlayFS. We
  93          * should check if there is a mount point using it with rootfs_data
  94          * as upperdir.
  95          */
  96         if (find_filesystem("overlay")) {
  97                 ULOG_ERR("overlayfs not supported by kernel\n");
  98                 return -1;
  99         }
 100
 101         v = volume_find("rootfs_data");
 102         if (!v) {
 103                 ULOG_ERR("MTD partition 'rootfs_data' not found\n");
 104                 return -1;
 105         }
 106
 107         if (!strcmp(*argv, "jffs2mark"))
 108                 return jffs2_mark(v);
 109         return jffs2_reset(v);
 110 }