xref: /illumos-gate/usr/src/cmd/fm/fmd/common/fmd_main.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/wait.h>
28 #include <sys/corectl.h>
29 #include <sys/resource.h>
30 
31 #include <priv_utils.h>
32 #include <signal.h>
33 #include <unistd.h>
34 #include <limits.h>
35 #include <fcntl.h>
36 #include <strings.h>
37 #include <stdlib.h>
38 #include <stdio.h>
39 #include <zone.h>
40 
41 #include <fmd_error.h>
42 #include <fmd_string.h>
43 #include <fmd_conf.h>
44 #include <fmd_dispq.h>
45 #include <fmd_subr.h>
46 #include <fmd.h>
47 
48 fmd_t fmd;
49 mutex_t _svcstate_lock = ERRORCHECKMUTEX;
50 
51 /*
52  * For DEBUG builds, we define a set of hooks for libumem that provide useful
53  * default settings for the allocator's debugging facilities.
54  */
55 #ifdef	DEBUG
56 const char *
57 _umem_debug_init()
58 {
59 	return ("default,verbose"); /* $UMEM_DEBUG setting */
60 }
61 
62 const char *
63 _umem_logging_init(void)
64 {
65 	return ("fail,contents"); /* $UMEM_LOGGING setting */
66 }
67 #endif	/* DEBUG */
68 
69 /*
70  * We use a two-phase algorithm for becoming a daemon because we want the
71  * daemon process (the child) to do the work of becoming MT-hot and opening our
72  * event transport.  Since these operations can fail and need to result in the
73  * daemon failing to start, the parent must wait until fmd_run() completes to
74  * know whether it can return zero or non-zero status to the invoking command.
75  * The parent waits on a pipe inside this function to read the exit status.
76  * The child gets the write-end of the pipe returned by daemonize_init() and
77  * then fmd_run() uses the pipe to set the exit status and detach the parent.
78  */
79 static int
80 daemonize_init(void)
81 {
82 	const char *gzp1, *gzp2, *gzp3, *gzp4, *gzp5;
83 	int status, pfds[2];
84 	sigset_t set, oset;
85 	struct rlimit rlim;
86 	char path[PATH_MAX];
87 	pid_t pid;
88 
89 	/*
90 	 * Set our per-process core file path to leave core files in our
91 	 * var/fm/fmd directory, named after the PID to aid in debugging,
92 	 * and make sure that there is no restriction on core file size.
93 	 */
94 	(void) snprintf(path, sizeof (path),
95 	    "%s/var/fm/fmd/core.%s.%%p", fmd.d_rootdir, fmd.d_pname);
96 
97 	(void) core_set_process_path(path, strlen(path) + 1, fmd.d_pid);
98 
99 	rlim.rlim_cur = RLIM_INFINITY;
100 	rlim.rlim_max = RLIM_INFINITY;
101 
102 	(void) setrlimit(RLIMIT_CORE, &rlim);
103 
104 	/*
105 	 * Claim all the file descriptors we can.
106 	 */
107 	if (getrlimit(RLIMIT_NOFILE, &rlim) == 0) {
108 		rlim.rlim_cur = rlim.rlim_max;
109 		(void) setrlimit(RLIMIT_NOFILE, &rlim);
110 	}
111 
112 	/*
113 	 * Reset all of our privilege sets to the minimum set of required
114 	 * privileges.  We continue to run as root so that files we create
115 	 * such as logs and checkpoints are secured in the /var filesystem.
116 	 *
117 	 * In a non-global zone some of the privileges we retain in a
118 	 * global zone are only optionally assigned to the zone, while others
119 	 * are prohibited:
120 	 *
121 	 * PRIV_PROC_PRIOCNTL (optional in a non-global zone):
122 	 *	There are no calls to priocntl(2) in fmd or plugins.
123 	 *
124 	 * PRIV_SYS_CONFIG (prohibited in a non-global zone):
125 	 *	Required, I think, for sysevent_post_event and/or
126 	 *	other legacy sysevent activity.  Legacy sysevent is not
127 	 *	supported in a non-global zone.
128 	 *
129 	 * PRIV_SYS_DEVICES (prohibited in a non-global zone):
130 	 *	Needed in the global zone for ioctls on various drivers
131 	 *	such as memory-controller drivers.
132 	 *
133 	 * PRIV_SYS_RES_CONFIG (prohibited in a non-global zone):
134 	 *	Require for p_online(2) calls to offline cpus.
135 	 *
136 	 * PRIV_SYS_NET_CONFIG (prohibited in a non-global zone):
137 	 *	Required for ipsec in etm (which also requires
138 	 *	PRIV_NET_PRIVADDR).
139 	 *
140 	 * We do without those privileges in a non-global zone.  It's
141 	 * possible that there are other privs we could drop since
142 	 * hardware-related plugins are not present.
143 	 */
144 	if (getzoneid() == GLOBAL_ZONEID) {
145 		gzp1 = PRIV_PROC_PRIOCNTL;
146 		gzp2 = PRIV_SYS_CONFIG;
147 		gzp3 = PRIV_SYS_DEVICES;
148 		gzp4 = PRIV_SYS_RES_CONFIG;
149 		gzp5 = PRIV_SYS_NET_CONFIG;
150 	} else {
151 		gzp1 = gzp2 = gzp3 = gzp4 = gzp5 = NULL;
152 	}
153 
154 	if (__init_daemon_priv(PU_RESETGROUPS | PU_LIMITPRIVS | PU_INHERITPRIVS,
155 	    0, 0, /* run as uid 0 and gid 0 */
156 	    PRIV_FILE_DAC_EXECUTE, PRIV_FILE_DAC_READ, PRIV_FILE_DAC_SEARCH,
157 	    PRIV_FILE_DAC_WRITE, PRIV_FILE_OWNER, PRIV_PROC_OWNER,
158 	    PRIV_SYS_ADMIN, PRIV_NET_PRIVADDR,
159 	    gzp1, gzp2, gzp3, gzp4, gzp5, NULL) != 0)
160 		fmd_error(EFMD_EXIT, "additional privileges required to run\n");
161 
162 	/*
163 	 * Block all signals prior to the fork and leave them blocked in the
164 	 * parent so we don't get in a situation where the parent gets SIGINT
165 	 * and returns non-zero exit status and the child is actually running.
166 	 * In the child, restore the signal mask once we've done our setsid().
167 	 */
168 	(void) sigfillset(&set);
169 	(void) sigdelset(&set, SIGABRT);
170 	(void) sigprocmask(SIG_BLOCK, &set, &oset);
171 
172 	if (pipe(pfds) == -1)
173 		fmd_error(EFMD_EXIT, "failed to create pipe for daemonize");
174 
175 	if ((pid = fork()) == -1)
176 		fmd_error(EFMD_EXIT, "failed to fork into background");
177 
178 	/*
179 	 * If we're the parent process, wait for either the child to send us
180 	 * the appropriate exit status over the pipe or for the read to fail
181 	 * (presumably with 0 for EOF if our child terminated abnormally).
182 	 * If the read fails, exit with either the child's exit status if it
183 	 * exited or with FMD_EXIT_ERROR if it died from a fatal signal.
184 	 */
185 	if (pid != 0) {
186 		(void) close(pfds[1]);
187 
188 		if (read(pfds[0], &status, sizeof (status)) == sizeof (status))
189 			_exit(status);
190 
191 		if (waitpid(pid, &status, 0) == pid && WIFEXITED(status))
192 			_exit(WEXITSTATUS(status));
193 
194 		_exit(FMD_EXIT_ERROR);
195 	}
196 
197 	fmd.d_pid = getpid();
198 	(void) setsid();
199 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
200 	(void) chdir("/");
201 	(void) umask(022);
202 	(void) close(pfds[0]);
203 
204 	return (pfds[1]);
205 }
206 
207 static void
208 daemonize_fini(int fd)
209 {
210 	(void) close(fd);
211 
212 	if ((fd = open("/dev/null", O_RDWR)) >= 0) {
213 		(void) fcntl(fd, F_DUP2FD, STDIN_FILENO);
214 		(void) fcntl(fd, F_DUP2FD, STDOUT_FILENO);
215 		(void) fcntl(fd, F_DUP2FD, STDERR_FILENO);
216 		(void) close(fd);
217 	}
218 }
219 
220 static void
221 handler(int sig)
222 {
223 	if (fmd.d_signal == 0)
224 		fmd.d_signal = sig;
225 }
226 
227 static int
228 usage(const char *arg0, FILE *fp)
229 {
230 	(void) fprintf(fp,
231 	    "Usage: %s [-V] [-f file] [-o opt=val] [-R dir]\n", arg0);
232 
233 	return (FMD_EXIT_USAGE);
234 }
235 
236 int
237 main(int argc, char *argv[])
238 {
239 	const char *opt_f = NULL, *opt_R = NULL;
240 	const char optstr[] = "f:o:R:V";
241 	int c, pfd = -1, opt_V = 0;
242 	char *p;
243 
244 	struct sigaction act;
245 	sigset_t set;
246 
247 	/*
248 	 * Parse the command-line once to validate all options and retrieve
249 	 * any overrides for our configuration file and root directory.
250 	 */
251 	while ((c = getopt(argc, argv, optstr)) != EOF) {
252 		switch (c) {
253 		case 'f':
254 			opt_f = optarg;
255 			break;
256 		case 'o':
257 			break; /* handle -o below */
258 		case 'R':
259 			opt_R = optarg;
260 			break;
261 		case 'V':
262 			opt_V++;
263 			break;
264 		default:
265 			return (usage(argv[0], stderr));
266 		}
267 	}
268 
269 	if (optind < argc)
270 		return (usage(argv[0], stderr));
271 
272 	if (opt_V) {
273 #ifdef DEBUG
274 		const char *debug = " (DEBUG)";
275 #else
276 		const char *debug = "";
277 #endif
278 		(void) printf("%s: version %s%s\n",
279 		    argv[0], _fmd_version, debug);
280 		return (FMD_EXIT_SUCCESS);
281 	}
282 
283 	closefrom(STDERR_FILENO + 1);
284 	fmd_create(&fmd, argv[0], opt_R, opt_f);
285 
286 	/*
287 	 * Now that we've initialized our global state, parse the command-line
288 	 * again for any configuration options specified using -o and set them.
289 	 */
290 	for (optind = 1; (c = getopt(argc, argv, optstr)) != EOF; ) {
291 		if (c == 'o') {
292 			if ((p = strchr(optarg, '=')) == NULL) {
293 				(void) fprintf(stderr, "%s: failed to set "
294 				    "option -o %s: option requires value\n",
295 				    fmd.d_pname, optarg);
296 				return (FMD_EXIT_USAGE);
297 			}
298 
299 			*p++ = '\0'; /* strike out the delimiter */
300 
301 			if (p[0] == '"' && p[strlen(p) - 1] == '"') {
302 				p[strlen(p) - 1] = '\0';
303 				(void) fmd_stresc2chr(++p);
304 			}
305 
306 			if (fmd_conf_setprop(fmd.d_conf, optarg, p) != 0) {
307 				(void) fprintf(stderr,
308 				    "%s: failed to set option -o %s: %s\n",
309 				    fmd.d_pname, optarg, fmd_strerror(errno));
310 				return (FMD_EXIT_USAGE);
311 			}
312 		}
313 	}
314 
315 	if (fmd.d_fmd_debug & FMD_DBG_HELP) {
316 		fmd_help(&fmd);
317 		fmd_destroy(&fmd);
318 		return (FMD_EXIT_SUCCESS);
319 	}
320 
321 	/*
322 	 * Update the value of fmd.d_fg based on "fg" in case it changed.  We
323 	 * use this property to decide whether to daemonize below.
324 	 */
325 	(void) fmd_conf_getprop(fmd.d_conf, "fg", &fmd.d_fg);
326 
327 	/*
328 	 * Once we're done setting our global state up, set up signal handlers
329 	 * for ensuring orderly termination on SIGTERM.  If we are starting in
330 	 * the foreground, we also use the same handler for SIGINT and SIGHUP.
331 	 */
332 	(void) sigfillset(&set);
333 	(void) sigdelset(&set, SIGABRT); /* always unblocked for ASSERT() */
334 
335 	(void) sigfillset(&act.sa_mask);
336 	act.sa_handler = handler;
337 	act.sa_flags = 0;
338 
339 	(void) sigaction(SIGTERM, &act, NULL);
340 	(void) sigdelset(&set, SIGTERM);
341 
342 	if (fmd.d_fg) {
343 		(void) sigaction(SIGHUP, &act, NULL);
344 		(void) sigdelset(&set, SIGHUP);
345 		(void) sigaction(SIGINT, &act, NULL);
346 		(void) sigdelset(&set, SIGINT);
347 
348 		(void) sigdelset(&set, SIGTSTP);
349 		(void) sigdelset(&set, SIGTTIN);
350 		(void) sigdelset(&set, SIGTTOU);
351 
352 		(void) printf("%s: [ loading modules ... ", fmd.d_pname);
353 		(void) fflush(stdout);
354 	} else
355 		pfd = daemonize_init();
356 
357 	/*
358 	 * Prior to this point, we are single-threaded.  Once fmd_run() is
359 	 * called, we will be multi-threaded from this point on.  The daemon's
360 	 * main thread will wait at the end of this function for signals.
361 	 */
362 	fmd_run(&fmd, pfd);
363 
364 	if (fmd.d_fg) {
365 		(void) printf("done ]\n");
366 		(void) printf("%s: [ awaiting events ]\n", fmd.d_pname);
367 	} else
368 		daemonize_fini(pfd);
369 
370 	while (!fmd.d_signal)
371 		(void) sigsuspend(&set);
372 
373 	fmd_destroy(&fmd);
374 	return (FMD_EXIT_SUCCESS);
375 }
376