1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Donn Seeley at Berkeley Software Design, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#) Copyright (c) 1991, 1993 The Regents of the University of California. All rights reserved. 33 * @(#)init.c 8.1 (Berkeley) 7/15/93 34 * $FreeBSD: src/sbin/init/init.c,v 1.38.2.8 2001/10/22 11:27:32 des Exp $ 35 */ 36 37 #include <sys/param.h> 38 #include <sys/ioctl.h> 39 #include <sys/mount.h> 40 #include <sys/sysctl.h> 41 #include <sys/wait.h> 42 #include <sys/stat.h> 43 44 #include <db.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <libutil.h> 48 #include <paths.h> 49 #include <signal.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <syslog.h> 54 #include <time.h> 55 #include <ttyent.h> 56 #include <unistd.h> 57 #include <sys/reboot.h> 58 #include <err.h> 59 60 #include <stdarg.h> 61 62 #include "pathnames.h" 63 64 static int setctty(const char *); 65 static void runcom(char **); 66 67 /* 68 * The mother of all processes. 69 */ 70 int 71 main(int argc __unused, char **argv) 72 { 73 /* Dispose of random users. */ 74 if (getuid() != 0) 75 errx(1, "%s", strerror(EPERM)); 76 77 /* Init is not allowed to die, it would make the kernel panic */ 78 signal(SIGTERM, SIG_IGN); 79 80 runcom(argv); 81 return 1; 82 } 83 84 static int 85 setctty(const char *name) 86 { 87 int fd; 88 89 revoke(name); 90 if ((fd = open(name, O_RDWR)) == -1) { 91 exit(1); 92 } 93 94 if (login_tty(fd) == -1) { 95 exit(1); 96 } 97 98 return fd; 99 } 100 101 102 static void 103 runcom(char **argv_orig) 104 { 105 pid_t pid, wpid; 106 int status, error; 107 const char *argv[4]; 108 struct sigaction sa; 109 110 if ((pid = fork()) == 0) { 111 sigemptyset(&sa.sa_mask); 112 sa.sa_flags = 0; 113 sa.sa_handler = SIG_IGN; 114 sigaction(SIGTSTP, &sa, NULL); 115 sigaction(SIGHUP, &sa, NULL); 116 117 setctty(_PATH_CONSOLE); 118 119 argv[0] = "sh"; 120 argv[1] = _PATH_RUNCOM; 121 argv[2] = "autoboot" ; 122 argv[3] = NULL; 123 124 sigprocmask(SIG_SETMASK, &sa.sa_mask, NULL); 125 126 execv(_PATH_BSHELL, __DECONST(char **, argv)); 127 exit(1); /* force single user mode */ 128 } 129 130 do { 131 wpid = waitpid(-1, &status, WUNTRACED); 132 } while (wpid != pid); 133 134 error = chdir(_PATH_NEWROOT); 135 if (error) 136 goto chroot_failed; 137 138 error = chroot_kernel(_PATH_NEWROOT); 139 if (error) 140 goto chroot_failed; 141 142 error = chroot(_PATH_NEWROOT); 143 if (error) 144 goto chroot_failed; 145 146 execv("/sbin/init", __DECONST(char **, argv_orig)); 147 148 /* We failed to exec /sbin/init in the chroot, sleep forever */ 149 chroot_failed: 150 while(1) { 151 sleep(3); 152 }; 153 } 154 155