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 #include <sys/reboot.h>
  18 #include <libubox/ulog.h>
  19
  20 #include <fcntl.h>
  21 #include <dirent.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <getopt.h>
  28
  29 #include <mtd/ubi-user.h>
  30
  31 #include "libfstools/libfstools.h"
  32 #include "libfstools/volume.h"
  33
  34 static int jffs2_mark(struct volume *v);
  35
  36 static int
  37 ask_user(void)
  38 {
  39         ULOG_WARN("This will erase all settings and remove any installed packages. Are you sure? [N/y]\n");
  40         if (getchar() != 'y')
  41                 return -1;
  42         return 0;
  43 }
  44
  45 static int jffs2_reset(struct volume *v, int reset, int keep)
  46 {
  47         char *mp;
  48
  49         mp = find_mount_point(v->blk, 1);
  50         if (mp) {
  51                 ULOG_INFO("%s is mounted as %s, only erasing files\n", v->blk, mp);
  52                 fs_state_set("/overlay", FS_STATE_PENDING);
  53                 overlay_delete(mp, keep);
  54                 mount(mp, "/", NULL, MS_REMOUNT, 0);
  55         } else {
  56                 ULOG_INFO("%s is not mounted\n", v->blk);
  57                 return jffs2_mark(v);
  58         }
  59
  60         if (reset) {
  61                 sync();
  62                 sleep(2);
  63                 reboot(RB_AUTOBOOT);
  64                 while (1)
  65                         ;
  66         }
  67
  68         return 0;
  69 }
  70
  71 static int jffs2_mark(struct volume *v)
  72 {
  73         __u32 deadc0de = __cpu_to_be32(0xdeadc0de);
  74         size_t sz;
  75         int fd;
  76
  77         fd = open(v->blk, O_WRONLY);
  78         ULOG_INFO("%s will be erased on next mount\n", v->blk);
  79         if (!fd) {
  80                 ULOG_ERR("opening %s failed\n", v->blk);
  81                 return -1;
  82         }
  83
  84         if (volume_identify(v) == FS_UBIFS) {
  85                 uint64_t llz = 0;
  86                 int ret = ioctl(fd, UBI_IOCVOLUP, &llz);
  87                 close(fd);
  88                 return ret;
  89         }
  90
  91         sz = write(fd, &deadc0de, sizeof(deadc0de));
  92         close(fd);
  93
  94         if (sz != 4) {
  95                 ULOG_ERR("writing %s failed: %m\n", v->blk);
  96                 return -1;
  97         }
  98
  99         return 0;
 100 }
 101
 102 int main(int argc, char **argv)
 103 {
 104         struct volume *v;
 105         int ch, yes = 0, reset = 0, keep = 0;
 106         while ((ch = getopt(argc, argv, "yrk")) != -1) {
 107                 switch(ch) {
 108                 case 'y':
 109                         yes = 1;
 110                         break;
 111                 case 'r':
 112                         reset = 1;
 113                         break;
 114                 case 'k':
 115                         keep = 1;
 116                         break;
 117                 }
 118
 119         }
 120
 121         if (!yes && ask_user())
 122                 return -1;
 123
 124         /*
 125          * TODO: Currently this only checks if kernel supports OverlayFS. We
 126          * should check if there is a mount point using it with rootfs_data
 127          * as upperdir.
 128          */
 129         if (find_filesystem("overlay")) {
 130                 ULOG_ERR("overlayfs not supported by kernel\n");
 131                 return -1;
 132         }
 133
 134         v = volume_find("rootfs_data");
 135         if (!v) {
 136                 ULOG_ERR("MTD partition 'rootfs_data' not found\n");
 137                 return -1;
 138         }
 139
 140         volume_init(v);
 141         if (!strcmp(*argv, "jffs2mark"))
 142                 return jffs2_mark(v);
 143         return jffs2_reset(v, reset, keep);
 144 }