xref: /titanic_41/usr/src/cmd/idmap/idmapd/idmapd.c (revision 16ba0fac26f672b18447f2e17a2f91f14ed3ce40)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 /*
28  * main() of idmapd(1M)
29  */
30 
31 #include "idmapd.h"
32 #include <atomic.h>
33 #include <signal.h>
34 #include <rpc/pmap_clnt.h> /* for pmap_unset */
35 #include <string.h> /* strcmp */
36 #include <unistd.h> /* setsid */
37 #include <sys/types.h>
38 #include <memory.h>
39 #include <stropts.h>
40 #include <netconfig.h>
41 #include <sys/resource.h> /* rlimit */
42 #include <rpcsvc/daemon_utils.h> /* DAEMON_UID and DAEMON_GID */
43 #include <priv_utils.h> /* privileges */
44 #include <locale.h>
45 #include <sys/systeminfo.h>
46 #include <errno.h>
47 #include <sys/wait.h>
48 #include <sys/time.h>
49 #include <zone.h>
50 #include <door.h>
51 #include <port.h>
52 #include <tsol/label.h>
53 #include <sys/resource.h>
54 #include <sys/sid.h>
55 #include <sys/idmap.h>
56 #include <pthread.h>
57 
58 static void	term_handler(int);
59 static void	init_idmapd();
60 static void	fini_idmapd();
61 
62 idmapd_state_t	_idmapdstate;
63 
64 SVCXPRT *xprt = NULL;
65 
66 static int dfd = -1;		/* our door server fildes, for unregistration */
67 static int degraded = 0;	/* whether the FMRI has been marked degraded */
68 
69 
70 static uint32_t		num_threads = 0;
71 static pthread_key_t	create_threads_key;
72 static uint32_t		max_threads = 40;
73 
74 
75 /*
76  * The following structure determines where the log messages from idmapdlog()
77  * go to. It can be stderr (idmapd -d) and/or the real idmapdlog (idmapd).
78  *
79  * logstate.max_pri is integer cutoff necessary to silence low-priority
80  * messages to stderr. idmapdlog has its own means so there a boolean
81  * logstate.write_idmapdlog is enough.
82  *
83  * logstate.degraded is a mode used by idmapd in its degraded state.
84  */
85 
86 static struct {
87 	boolean_t write_syslog;
88 	int max_pri; /* Max priority written to stderr */
89 	boolean_t degraded;
90 } logstate = {B_FALSE, LOG_DEBUG, B_FALSE};
91 
92 /*
93  * Server door thread start routine.
94  *
95  * Set a TSD value to the door thread. This enables the destructor to
96  * be called when this thread exits.
97  */
98 /*ARGSUSED*/
99 static void *
100 idmapd_door_thread_start(void *arg)
101 {
102 	static void *value = 0;
103 
104 	/*
105 	 * Disable cancellation to avoid memory leaks from not running
106 	 * the thread cleanup code.
107 	 */
108 	(void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
109 	(void) pthread_setspecific(create_threads_key, value);
110 	(void) door_return(NULL, 0, NULL, 0);
111 
112 	/* make lint happy */
113 	return (NULL);
114 }
115 
116 /*
117  * Server door threads creation
118  */
119 /*ARGSUSED*/
120 static void
121 idmapd_door_thread_create(door_info_t *dip)
122 {
123 	int		num;
124 	pthread_t	thread_id;
125 
126 	if ((num = atomic_inc_32_nv(&num_threads)) > max_threads) {
127 		atomic_dec_32(&num_threads);
128 		idmapdlog(LOG_DEBUG,
129 		    "thread creation refused - %d threads currently active",
130 		    num - 1);
131 		return;
132 	}
133 	(void) pthread_create(&thread_id, NULL, idmapd_door_thread_start, NULL);
134 	idmapdlog(LOG_DEBUG,
135 	    "created thread ID %d - %d threads currently active",
136 	    thread_id, num);
137 }
138 
139 /*
140  * Server door thread cleanup
141  */
142 /*ARGSUSED*/
143 static void
144 idmapd_door_thread_cleanup(void *arg)
145 {
146 	int num;
147 
148 	num = atomic_dec_32_nv(&num_threads);
149 	idmapdlog(LOG_DEBUG,
150 	    "exiting thread ID %d - %d threads currently active",
151 	    pthread_self(), num);
152 }
153 
154 /*
155  * This is needed for mech_krb5 -- we run as daemon, yes, but we want
156  * mech_krb5 to think we're root so it can get host/nodename.fqdn
157  * tickets for us so we can authenticate to AD as the machine account
158  * that we are.  For more details look at the entry point in mech_krb5
159  * corresponding to gss_init_sec_context().
160  *
161  * As a side effect of faking our effective UID to mech_krb5 we will use
162  * root's default ccache (/tmp/krb5cc_0).  But if that's created by
163  * another process then we won't have access to it: we run as daemon and
164  * keep PRIV_FILE_DAC_READ, which is insufficient to share the ccache
165  * with others.  We putenv("KRB5CCNAME=/var/run/idmap/ccache") in main()
166  * to avoid this issue; see main().
167  *
168  * Someday we'll have gss/mech_krb5 extensions for acquiring initiator
169  * creds with keytabs/raw keys, and someday we'll have extensions to
170  * libsasl to specify creds/name to use on the initiator side, and
171  * someday we'll have extensions to libldap to pass those through to
172  * libsasl.  Until then this interposer will have to do.
173  *
174  * Also, we have to tell lint to shut up: it thinks app_krb5_user_uid()
175  * is defined but not used.
176  */
177 /*LINTLIBRARY*/
178 uid_t
179 app_krb5_user_uid(void)
180 {
181 	return (0);
182 }
183 
184 /*ARGSUSED*/
185 static void
186 term_handler(int sig)
187 {
188 	idmapdlog(LOG_INFO, "Terminating.");
189 	fini_idmapd();
190 	_exit(0);
191 }
192 
193 /*ARGSUSED*/
194 static void
195 usr1_handler(int sig)
196 {
197 	boolean_t saved_debug_mode = _idmapdstate.debug_mode;
198 
199 	_idmapdstate.debug_mode = B_TRUE;
200 	idmap_log_stderr(LOG_DEBUG);
201 
202 	print_idmapdstate();
203 
204 	_idmapdstate.debug_mode = saved_debug_mode;
205 	idmap_log_stderr(_idmapdstate.daemon_mode ? -1 : LOG_DEBUG);
206 
207 }
208 
209 static int pipe_fd = -1;
210 
211 static void
212 daemonize_ready(void)
213 {
214 	char data = '\0';
215 	/*
216 	 * wake the parent
217 	 */
218 	(void) write(pipe_fd, &data, 1);
219 	(void) close(pipe_fd);
220 }
221 
222 static int
223 daemonize_start(void)
224 {
225 	char	data;
226 	int	status;
227 	int	devnull;
228 	int	filedes[2];
229 	pid_t	pid;
230 
231 	(void) sigset(SIGPIPE, SIG_IGN);
232 	devnull = open("/dev/null", O_RDONLY);
233 	if (devnull < 0)
234 		return (-1);
235 	(void) dup2(devnull, 0);
236 	(void) dup2(2, 1);	/* stderr only */
237 	if (pipe(filedes) < 0)
238 		return (-1);
239 	if ((pid = fork1()) < 0)
240 		return (-1);
241 	if (pid != 0) {
242 		/*
243 		 * parent
244 		 */
245 		(void) close(filedes[1]);
246 		if (read(filedes[0], &data, 1) == 1) {
247 			/* presume success */
248 			_exit(0);
249 		}
250 		status = -1;
251 		(void) wait4(pid, &status, 0, NULL);
252 		if (WIFEXITED(status))
253 			_exit(WEXITSTATUS(status));
254 		else
255 			_exit(-1);
256 	}
257 
258 	/*
259 	 * child
260 	 */
261 	pipe_fd = filedes[1];
262 	(void) close(filedes[0]);
263 	(void) setsid();
264 	(void) umask(0077);
265 	openlog("idmap", LOG_PID, LOG_DAEMON);
266 
267 	return (0);
268 }
269 
270 
271 int
272 main(int argc, char **argv)
273 {
274 	int c;
275 	struct rlimit rl;
276 
277 	_idmapdstate.daemon_mode = TRUE;
278 	_idmapdstate.debug_mode = FALSE;
279 	while ((c = getopt(argc, argv, "d")) != -1) {
280 		switch (c) {
281 			case 'd':
282 				_idmapdstate.daemon_mode = FALSE;
283 				break;
284 			default:
285 				(void) fprintf(stderr,
286 				    "Usage: /usr/lib/idmapd [-d]\n");
287 				return (SMF_EXIT_ERR_CONFIG);
288 		}
289 	}
290 
291 	/* set locale and domain for internationalization */
292 	(void) setlocale(LC_ALL, "");
293 	(void) textdomain(TEXT_DOMAIN);
294 
295 	idmap_set_logger(idmapdlog);
296 	idmap_log_syslog(B_TRUE);
297 	idmap_log_stderr(_idmapdstate.daemon_mode ? -1 : LOG_DEBUG);
298 
299 	if (is_system_labeled() && getzoneid() != GLOBAL_ZONEID) {
300 		idmapdlog(LOG_ERR,
301 		    "with Trusted Extensions idmapd runs only in the "
302 		    "global zone");
303 		exit(1);
304 	}
305 
306 	/*
307 	 * Raise the fd limit to max
308 	 */
309 	if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
310 		idmapdlog(LOG_ERR, "getrlimit failed");
311 	} else if (rl.rlim_cur < rl.rlim_max) {
312 		rl.rlim_cur = rl.rlim_max;
313 		if (setrlimit(RLIMIT_NOFILE, &rl) != 0)
314 			idmapdlog(LOG_ERR,
315 			    "Unable to raise RLIMIT_NOFILE to %d",
316 			    rl.rlim_cur);
317 	}
318 
319 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
320 
321 	if (_idmapdstate.daemon_mode == TRUE) {
322 		if (daemonize_start() < 0) {
323 			idmapdlog(LOG_ERR, "unable to daemonize");
324 			exit(-1);
325 		}
326 	} else
327 		(void) umask(0077);
328 
329 	idmap_init_tsd_key();
330 
331 	init_idmapd();
332 
333 	/* signal handlers that should run only after we're initialized */
334 	(void) sigset(SIGTERM, term_handler);
335 	(void) sigset(SIGUSR1, usr1_handler);
336 	(void) sigset(SIGHUP, idmap_cfg_hup_handler);
337 
338 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
339 	    DAEMON_UID, DAEMON_GID,
340 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
341 	    (char *)NULL) == -1) {
342 		idmapdlog(LOG_ERR, "unable to drop privileges");
343 		exit(1);
344 	}
345 
346 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
347 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
348 
349 	if (_idmapdstate.daemon_mode == TRUE)
350 		daemonize_ready();
351 
352 	/* With doors RPC this just wastes this thread, oh well */
353 	svc_run();
354 	return (0);
355 }
356 
357 static void
358 init_idmapd()
359 {
360 	int	error;
361 	int	connmaxrec = IDMAP_MAX_DOOR_RPC;
362 
363 
364 	/* create directories as root and chown to daemon uid */
365 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
366 		exit(1);
367 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
368 		exit(1);
369 
370 	/*
371 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
372 	 * for more details.  We blow away the existing one, if there is
373 	 * one.
374 	 */
375 	(void) unlink(IDMAP_CACHEDIR "/ccache");
376 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
377 
378 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
379 	    sizeof (_idmapdstate.hostname)) == -1) {
380 		error = errno;
381 		idmapdlog(LOG_ERR, "unable to determine hostname, error: %d",
382 		    error);
383 		exit(1);
384 	}
385 
386 	if ((error = init_mapping_system()) < 0) {
387 		idmapdlog(LOG_ERR, "unable to initialize mapping system");
388 		exit(error < -2 ? SMF_EXIT_ERR_CONFIG : 1);
389 	}
390 
391 	(void) door_server_create(idmapd_door_thread_create);
392 	if ((error = pthread_key_create(&create_threads_key,
393 	    idmapd_door_thread_cleanup)) != 0) {
394 		idmapdlog(LOG_ERR, "unable to create threads key (%s)",
395 		    strerror(error));
396 		goto errout;
397 	}
398 
399 	xprt = svc_door_create(idmap_prog_1, IDMAP_PROG, IDMAP_V1, connmaxrec);
400 	if (xprt == NULL) {
401 		idmapdlog(LOG_ERR, "unable to create door RPC service");
402 		goto errout;
403 	}
404 
405 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
406 		idmapdlog(LOG_ERR, "unable to limit RPC request size");
407 		goto errout;
408 	}
409 
410 	dfd = xprt->xp_fd;
411 
412 	if (dfd == -1) {
413 		idmapdlog(LOG_ERR, "unable to register door");
414 		goto errout;
415 	}
416 	if ((error = idmap_reg(dfd)) != 0) {
417 		idmapdlog(LOG_ERR, "unable to register door (%s)",
418 		    strerror(errno));
419 		goto errout;
420 	}
421 
422 	if ((error = allocids(_idmapdstate.new_eph_db,
423 	    8192, &_idmapdstate.next_uid,
424 	    8192, &_idmapdstate.next_gid)) != 0) {
425 		idmapdlog(LOG_ERR, "unable to allocate ephemeral IDs (%s)",
426 		    strerror(errno));
427 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
428 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
429 	} else {
430 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
431 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
432 	}
433 
434 	print_idmapdstate();
435 
436 	return;
437 
438 errout:
439 	fini_idmapd();
440 	exit(1);
441 }
442 
443 static void
444 fini_idmapd()
445 {
446 	idmap_unreg(dfd);
447 	fini_mapping_system();
448 	if (xprt != NULL)
449 		svc_destroy(xprt);
450 }
451 
452 static
453 const char *
454 get_fmri(void)
455 {
456 	static char *fmri = NULL;
457 	static char buf[60];
458 	char *s;
459 
460 	membar_consumer();
461 	s = fmri;
462 	if (s != NULL && *s == '\0')
463 		return (NULL);
464 	else if (s != NULL)
465 		return (s);
466 
467 	if ((s = getenv("SMF_FMRI")) == NULL || strlen(s) >= sizeof (buf))
468 		buf[0] = '\0';
469 	else
470 		(void) strlcpy(buf, s, sizeof (buf));
471 
472 	membar_producer();
473 	fmri = buf;
474 
475 	return (get_fmri());
476 }
477 
478 /*
479  * Wrappers for smf_degrade/restore_instance()
480  *
481  * smf_restore_instance() is too heavy duty to be calling every time we
482  * have a successful AD name<->SID lookup.
483  */
484 void
485 degrade_svc(int poke_discovery, const char *reason)
486 {
487 	const char *fmri;
488 
489 	/*
490 	 * If the config update thread is in a state where auto-discovery could
491 	 * be re-tried, then this will make it try it -- a sort of auto-refresh.
492 	 */
493 	if (poke_discovery)
494 		idmap_cfg_poke_updates();
495 
496 	membar_consumer();
497 	if (degraded)
498 		return;
499 
500 	idmapdlog(LOG_ERR, "Degraded operation (%s).  If you are running an "
501 	    "SMB server in workgroup mode, or if you're not running an SMB "
502 	    "server, then you can ignore this message", reason);
503 
504 	membar_producer();
505 	degraded = 1;
506 	idmap_log_degraded(B_TRUE);
507 
508 	if ((fmri = get_fmri()) != NULL)
509 		(void) smf_degrade_instance(fmri, 0);
510 }
511 
512 void
513 restore_svc(void)
514 {
515 	const char *fmri;
516 
517 	membar_consumer();
518 	if (!degraded)
519 		return;
520 
521 	if ((fmri = get_fmri()) == NULL)
522 		(void) smf_restore_instance(fmri);
523 
524 	membar_producer();
525 	degraded = 0;
526 	idmap_log_degraded(B_FALSE);
527 
528 	idmapdlog(LOG_NOTICE, "Normal operation restored");
529 }
530 
531 
532 /* printflike */
533 void
534 idmapdlog(int pri, const char *format, ...) {
535 	va_list args;
536 
537 	if (pri <= logstate.max_pri) {
538 		va_start(args, format);
539 		(void) vfprintf(stderr, format, args);
540 		(void) fprintf(stderr, "\n");
541 		va_end(args);
542 	}
543 
544 	/*
545 	 * We don't want to fill up the logs with useless messages when
546 	 * we're degraded, but we still want to log.
547 	 */
548 	if (logstate.degraded)
549 		pri = LOG_DEBUG;
550 
551 	if (logstate.write_syslog) {
552 		va_start(args, format);
553 		vsyslog(pri, format, args);
554 		va_end(args);
555 	}
556 }
557 
558 void
559 idmap_log_stderr(int pri)
560 {
561 	logstate.max_pri = pri;
562 }
563 
564 void
565 idmap_log_syslog(boolean_t what)
566 {
567 	logstate.write_syslog = what;
568 }
569 
570 void
571 idmap_log_degraded(boolean_t what)
572 {
573 	logstate.degraded = what;
574 }
575