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
  19 #include <stdio.h>
  20 #include <fcntl.h>
  21 #include <unistd.h>
  22 #include <stdlib.h>
  23
  24 #include "../utils/utils.h"
  25 #include "init.h"
  26 #include "../libc-compat.h"
  27
  28 static void
  29 early_dev(void)
  30 {
  31         mkdev("*", 0600);
  32         mknod("/dev/null", 0666, makedev(1, 3));
  33 }
  34
  35 static void
  36 early_console(const char *dev)
  37 {
  38         struct stat s;
  39
  40         if (stat(dev, &s)) {
  41                 ERROR("Failed to stat %s\n", dev);
  42                 return;
  43         }
  44
  45         if (patch_stdio(dev)) {
  46                 ERROR("Failed to setup i/o redirection\n");
  47                 return;
  48         }
  49
  50         fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
  51 }
  52
  53 static void
  54 early_mounts(void)
  55 {
  56         unsigned int oldumask = umask(0);
  57
  58         mount("proc", "/proc", "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  59         mount("sysfs", "/sys", "sysfs", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  60         mount("cgroup", "/sys/fs/cgroup", "cgroup",  MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  61         mount("tmpfs", "/dev", "tmpfs", MS_NOATIME | MS_NOSUID, "mode=0755,size=512K");
  62         ignore(symlink("/tmp/shm", "/dev/shm"));
  63         mkdir("/dev/pts", 0755);
  64         mount("devpts", "/dev/pts", "devpts", MS_NOATIME | MS_NOEXEC | MS_NOSUID, "mode=600");
  65         early_dev();
  66
  67         early_console("/dev/console");
  68         if (mount_zram_on_tmp()) {
  69                 mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME, 0);
  70                 mkdir("/tmp/shm", 01777);
  71         } else {
  72                 mkdir("/tmp/shm", 01777);
  73                 mount("tmpfs", "/tmp/shm", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME,
  74                                 "mode=01777");
  75         }
  76         mkdir("/tmp/run", 0755);
  77         mkdir("/tmp/lock", 0755);
  78         mkdir("/tmp/state", 0755);
  79         umask(oldumask);
  80 }
  81
  82 static void
  83 early_env(void)
  84 {
  85         setenv("PATH", EARLY_PATH, 1);
  86 }
  87
  88 void
  89 early(void)
  90 {
  91         if (getpid() != 1)
  92                 return;
  93
  94         early_mounts();
  95         early_env();
  96
  97         LOG("Console is alive\n");
  98 }