1 /* $OpenBSD: hotplugd.c,v 1.12 2010/01/10 13:20:41 grange Exp $ */ 2 /* 3 * Copyright (c) 2004 Alexander Yurchenko <grange@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 /* 19 * Devices hot plugging daemon. 20 */ 21 22 #include <sys/types.h> 23 #include <sys/device.h> 24 #include <sys/hotplug.h> 25 #include <sys/wait.h> 26 27 #include <err.h> 28 #include <errno.h> 29 #include <fcntl.h> 30 #include <libgen.h> 31 #include <signal.h> 32 #include <stdarg.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <syslog.h> 37 #include <unistd.h> 38 39 #define _PATH_DEV_HOTPLUG "/dev/hotplug" 40 #define _PATH_ETC_HOTPLUG "/etc/hotplug" 41 #define _PATH_ETC_HOTPLUG_ATTACH _PATH_ETC_HOTPLUG "/attach" 42 #define _PATH_ETC_HOTPLUG_DETACH _PATH_ETC_HOTPLUG "/detach" 43 #define _LOG_TAG "hotplugd" 44 #define _LOG_FACILITY LOG_DAEMON 45 #define _LOG_OPT (LOG_NDELAY | LOG_PID) 46 47 volatile sig_atomic_t quit = 0; 48 char *device = _PATH_DEV_HOTPLUG; 49 int devfd = -1; 50 51 void exec_script(const char *, int, char *); 52 53 void sigchild(int); 54 void sigquit(int); 55 __dead void usage(void); 56 57 int 58 main(int argc, char *argv[]) 59 { 60 int ch; 61 struct sigaction sact; 62 struct hotplug_event he; 63 64 while ((ch = getopt(argc, argv, "d:")) != -1) 65 switch (ch) { 66 case 'd': 67 device = optarg; 68 break; 69 case '?': 70 default: 71 usage(); 72 /* NOTREACHED */ 73 } 74 75 argc -= optind; 76 argv += optind; 77 if (argc > 0) 78 usage(); 79 80 if ((devfd = open(device, O_RDONLY)) == -1) 81 err(1, "%s", device); 82 83 bzero(&sact, sizeof(sact)); 84 sigemptyset(&sact.sa_mask); 85 sact.sa_flags = 0; 86 sact.sa_handler = sigquit; 87 sigaction(SIGINT, &sact, NULL); 88 sigaction(SIGQUIT, &sact, NULL); 89 sigaction(SIGTERM, &sact, NULL); 90 sact.sa_handler = SIG_IGN; 91 sigaction(SIGHUP, &sact, NULL); 92 sact.sa_handler = sigchild; 93 sact.sa_flags = SA_NOCLDSTOP; 94 sigaction(SIGCHLD, &sact, NULL); 95 96 openlog(_LOG_TAG, _LOG_OPT, _LOG_FACILITY); 97 if (daemon(0, 0) == -1) 98 err(1, "daemon"); 99 100 syslog(LOG_INFO, "started"); 101 102 while (!quit) { 103 if (read(devfd, &he, sizeof(he)) == -1) { 104 if (errno == EINTR) 105 /* ignore */ 106 continue; 107 syslog(LOG_ERR, "read: %m"); 108 exit(1); 109 } 110 111 switch (he.he_type) { 112 case HOTPLUG_DEVAT: 113 syslog(LOG_INFO, "%s attached, class %d", 114 he.he_devname, he.he_devclass); 115 exec_script(_PATH_ETC_HOTPLUG_ATTACH, he.he_devclass, 116 he.he_devname); 117 break; 118 case HOTPLUG_DEVDT: 119 syslog(LOG_INFO, "%s detached, class %d", 120 he.he_devname, he.he_devclass); 121 exec_script(_PATH_ETC_HOTPLUG_DETACH, he.he_devclass, 122 he.he_devname); 123 break; 124 default: 125 syslog(LOG_NOTICE, "unknown event (0x%x)", he.he_type); 126 } 127 } 128 129 syslog(LOG_INFO, "terminated"); 130 131 closelog(); 132 close(devfd); 133 134 return (0); 135 } 136 137 void 138 exec_script(const char *file, int class, char *name) 139 { 140 char strclass[8]; 141 pid_t pid; 142 143 snprintf(strclass, sizeof(strclass), "%d", class); 144 145 if (access(file, X_OK | R_OK) == -1) { 146 if (errno != ENOENT) 147 syslog(LOG_ERR, "%s: %m", file); 148 return; 149 } 150 151 if ((pid = fork()) == -1) { 152 syslog(LOG_ERR, "fork: %m"); 153 return; 154 } 155 if (pid == 0) { 156 /* child process */ 157 execl(file, basename(file), strclass, name, (char *)NULL); 158 syslog(LOG_ERR, "execl %s: %m", file); 159 _exit(1); 160 /* NOTREACHED */ 161 } 162 } 163 164 /* ARGSUSED */ 165 void 166 sigchild(int signum) 167 { 168 struct syslog_data sdata = SYSLOG_DATA_INIT; 169 int saved_errno, status; 170 pid_t pid; 171 172 saved_errno = errno; 173 174 sdata.log_tag = _LOG_TAG; 175 sdata.log_fac = _LOG_FACILITY; 176 sdata.log_stat = _LOG_OPT; 177 178 while ((pid = waitpid(WAIT_ANY, &status, WNOHANG)) != 0) { 179 if (pid == -1) { 180 if (errno == EINTR) 181 continue; 182 if (errno != ECHILD) 183 syslog_r(LOG_ERR, &sdata, "waitpid: %m"); 184 break; 185 } 186 187 if (WIFEXITED(status)) { 188 if (WEXITSTATUS(status) != 0) { 189 syslog_r(LOG_NOTICE, &sdata, 190 "child exit status: %d", 191 WEXITSTATUS(status)); 192 } 193 } else { 194 syslog_r(LOG_NOTICE, &sdata, 195 "child is terminated abnormally"); 196 } 197 } 198 199 errno = saved_errno; 200 } 201 202 /* ARGSUSED */ 203 void 204 sigquit(int signum) 205 { 206 quit = 1; 207 } 208 209 __dead void 210 usage(void) 211 { 212 extern char *__progname; 213 214 fprintf(stderr, "usage: %s [-d device]\n", __progname); 215 exit(1); 216 } 217