initd/early.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/mount.h>
  16 #include <sys/types.h>
  17 #include <sys/stat.h>
  18 #include <sys/sysmacros.h>
  19
  20 #include <stdio.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24
  25 #include "../utils/utils.h"
  26 #include "init.h"
  27 #include "../libc-compat.h"
  28
  29 static void
  30 early_dev(void)
  31 {
  32         mkdev("*", 0600);
  33         mknod("/dev/null", 0666, makedev(1, 3));
  34 }
  35
  36 static void
  37 early_console(const char *dev)
  38 {
  39         struct stat s;
  40
  41         if (stat(dev, &s)) {
  42                 ERROR("Failed to stat %s: %m\n", dev);
  43                 return;
  44         }
  45
  46         if (patch_stdio(dev)) {
  47                 ERROR("Failed to setup i/o redirection\n");
  48                 return;
  49         }
  50
  51         fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
  52 }
  53
  54 static void
  55 early_mounts(void)
  56 {
  57         unsigned int oldumask = umask(0);
  58
  59         mount("proc", "/proc", "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  60         mount("sysfs", "/sys", "sysfs", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  61         mount("cgroup", "/sys/fs/cgroup", "cgroup",  MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  62         mount("tmpfs", "/dev", "tmpfs", MS_NOATIME | MS_NOSUID, "mode=0755,size=512K");
  63         ignore(symlink("/tmp/shm", "/dev/shm"));
  64         mkdir("/dev/pts", 0755);
  65         mount("devpts", "/dev/pts", "devpts", MS_NOATIME | MS_NOEXEC | MS_NOSUID, "mode=600");
  66         early_dev();
  67
  68         early_console("/dev/console");
  69         if (mount_zram_on_tmp()) {
  70                 mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME, "mode=01777");
  71                 mkdir("/tmp/shm", 01777);
  72         } else {
  73                 mkdir("/tmp/shm", 01777);
  74                 mount("tmpfs", "/tmp/shm", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME,
  75                                 "mode=01777");
  76         }
  77         mkdir("/tmp/run", 0755);
  78         mkdir("/tmp/lock", 0755);
  79         mkdir("/tmp/state", 0755);
  80         umask(oldumask);
  81 }
  82
  83 static void
  84 early_env(void)
  85 {
  86         setenv("PATH", EARLY_PATH, 1);
  87 }
  88
  89 void
  90 early(void)
  91 {
  92         if (getpid() != 1)
  93                 return;
  94
  95         early_mounts();
  96         early_env();
  97
  98         LOG("Console is alive\n");
  99 }