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 <errno.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27
  28 #include <libubox/blobmsg.h>
  29
  30 void sysupgrade_exec_upgraded(const char *prefix, char *path,
  31                               const char *backup, char *command,
  32                               struct blob_attr *options)
  33 {
  34         char *wdt_fd = watchdog_fd();
  35         char *argv[] = { "/sbin/upgraded", NULL, NULL, NULL};
  36         struct blob_attr *option;
  37         int rem;
  38         int ret;
  39
  40         ret = chroot(prefix);
  41         if (ret < 0) {
  42                 fprintf(stderr, "Failed to chroot for upgraded exec.\n");
  43                 return;
  44         }
  45
  46         argv[1] = path;
  47         argv[2] = command;
  48
  49         if (wdt_fd) {
  50                 watchdog_set_cloexec(false);
  51                 setenv("WDTFD", wdt_fd, 1);
  52         }
  53
  54         if (backup)
  55                 setenv("UPGRADE_BACKUP", backup, 1);
  56
  57         blobmsg_for_each_attr(option, options, rem) {
  58                 const char *prefix = "UPGRADE_OPT_";
  59                 char value[11];
  60                 char *name;
  61                 char *c;
  62                 int tmp;
  63
  64                 if (asprintf(&name, "%s%s", prefix, blobmsg_name(option)) <= 0)
  65                         continue;
  66                 for (c = name + strlen(prefix); *c; c++) {
  67                         if (isalnum(*c) || *c == '_') {
  68                                 *c = toupper(*c);
  69                         } else {
  70                                 c = NULL;
  71                                 break;
  72                         }
  73                 }
  74
  75                 if (!c) {
  76                         fprintf(stderr, "Option \"%s\" contains invalid characters\n",
  77                                 blobmsg_name(option));
  78                         free(name);
  79                         continue;
  80                 }
  81
  82                 switch (blobmsg_type(option)) {
  83                 case BLOBMSG_TYPE_INT32:
  84                         tmp = blobmsg_get_u32(option);
  85                         break;
  86                 case BLOBMSG_TYPE_INT16:
  87                         tmp = blobmsg_get_u16(option);
  88                         break;
  89                 case BLOBMSG_TYPE_INT8:
  90                         tmp = blobmsg_get_u8(option);
  91                         break;
  92                 default:
  93                         fprintf(stderr, "Option \"%s\" has unsupported type: %d\n",
  94                                 blobmsg_name(option), blobmsg_type(option));
  95                         free(name);
  96                         continue;
  97                 }
  98                 snprintf(value, sizeof(value), "%u", tmp);
  99
 100                 setenv(name, value, 1);
 101
 102                 free(name);
 103         }
 104
 105         execvp(argv[0], argv);
 106
 107         /* Cleanup on failure */
 108         fprintf(stderr, "Failed to exec upgraded: %s\n", strerror(-errno));
 109         unsetenv("WDTFD");
 110         watchdog_set_cloexec(true);
 111         ret = chroot(".");
 112         if (ret < 0) {
 113                 fprintf(stderr, "Failed to reset chroot, exiting.\n");
 114                 exit(EXIT_FAILURE);
 115         }
 116 }