sysupgrade.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  * Copyright (C) 2017 Matthias Schiffer <mschiffer@universe-factory.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU Lesser General Public License version 2.1
   8  * as published by the Free Software Foundation
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16
  17 #define _GNU_SOURCE
  18 #include "watchdog.h"
  19 #include "sysupgrade.h"
  20
  21 #include <ctype.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 #include <libubox/blobmsg.h>
  27
  28 void sysupgrade_exec_upgraded(const char *prefix, char *path,
  29                               const char *backup, char *command,
  30                               struct blob_attr *options)
  31 {
  32         char *wdt_fd = watchdog_fd();
  33         char *argv[] = { "/sbin/upgraded", NULL, NULL, NULL};
  34         struct blob_attr *option;
  35         int rem;
  36         int ret;
  37
  38         ret = chroot(prefix);
  39         if (ret < 0) {
  40                 fprintf(stderr, "Failed to chroot for upgraded exec.\n");
  41                 return;
  42         }
  43
  44         argv[1] = path;
  45         argv[2] = command;
  46
  47         if (wdt_fd) {
  48                 watchdog_set_cloexec(false);
  49                 setenv("WDTFD", wdt_fd, 1);
  50         }
  51
  52         if (backup)
  53                 setenv("UPGRADE_BACKUP", backup, 1);
  54
  55         blobmsg_for_each_attr(option, options, rem) {
  56                 const char *prefix = "UPGRADE_OPT_";
  57                 char value[11];
  58                 char *name;
  59                 char *c;
  60                 int tmp;
  61
  62                 if (asprintf(&name, "%s%s", prefix, blobmsg_name(option)) <= 0)
  63                         continue;
  64                 for (c = name + strlen(prefix); *c; c++) {
  65                         if (isalnum(*c) || *c == '_') {
  66                                 *c = toupper(*c);
  67                         } else {
  68                                 c = NULL;
  69                                 break;
  70                         }
  71                 }
  72
  73                 if (!c) {
  74                         fprintf(stderr, "Option \"%s\" contains invalid characters\n",
  75                                 blobmsg_name(option));
  76                         free(name);
  77                         continue;
  78                 }
  79
  80                 switch (blobmsg_type(option)) {
  81                 case BLOBMSG_TYPE_INT32:
  82                         tmp = blobmsg_get_u32(option);
  83                         break;
  84                 case BLOBMSG_TYPE_INT16:
  85                         tmp = blobmsg_get_u16(option);
  86                         break;
  87                 case BLOBMSG_TYPE_INT8:
  88                         tmp = blobmsg_get_u8(option);
  89                         break;
  90                 default:
  91                         fprintf(stderr, "Option \"%s\" has unsupported type: %d\n",
  92                                 blobmsg_name(option), blobmsg_type(option));
  93                         free(name);
  94                         continue;
  95                 }
  96                 snprintf(value, sizeof(value), "%u", tmp);
  97
  98                 setenv(name, value, 1);
  99
 100                 free(name);
 101         }
 102
 103         execvp(argv[0], argv);
 104
 105         /* Cleanup on failure */
 106         fprintf(stderr, "Failed to exec upgraded.\n");
 107         unsetenv("WDTFD");
 108         watchdog_set_cloexec(true);
 109         ret = chroot(".");
 110         if (ret < 0) {
 111                 fprintf(stderr, "Failed to reset chroot, exiting.\n");
 112                 exit(EXIT_FAILURE);
 113         }
 114 }