xref: /titanic_44/usr/src/cmd/idmap/idmapd/idmapd.c (revision 410c4fb9ef2c1b77143344000d65f79d388900d8)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * main() of idmapd(1M)
30  */
31 
32 #include "idmapd.h"
33 #include <atomic.h>
34 #include <signal.h>
35 #include <rpc/pmap_clnt.h> /* for pmap_unset */
36 #include <string.h> /* strcmp */
37 #include <unistd.h> /* setsid */
38 #include <sys/types.h>
39 #include <memory.h>
40 #include <stropts.h>
41 #include <netconfig.h>
42 #include <sys/resource.h> /* rlimit */
43 #include <syslog.h>
44 #include <rpcsvc/daemon_utils.h> /* DAEMON_UID and DAEMON_GID */
45 #include <priv_utils.h> /* privileges */
46 #include <locale.h>
47 #include <sys/systeminfo.h>
48 #include <errno.h>
49 #include <sys/wait.h>
50 #include <sys/time.h>
51 #include <zone.h>
52 #include <door.h>
53 #include <port.h>
54 #include <tsol/label.h>
55 #include <sys/resource.h>
56 #include <sys/sid.h>
57 #include <sys/idmap.h>
58 
59 static void	term_handler(int);
60 static void	init_idmapd();
61 static void	fini_idmapd();
62 
63 #define	_RPCSVC_CLOSEDOWN 120
64 
65 int _rpcsvcstate = _IDLE;	/* Set when a request is serviced */
66 int _rpcsvccount = 0;		/* Number of requests being serviced */
67 mutex_t _svcstate_lock;		/* lock for _rpcsvcstate, _rpcsvccount */
68 idmapd_state_t	_idmapdstate;
69 
70 SVCXPRT *xprt = NULL;
71 
72 static int dfd = -1;		/* our door server fildes, for unregistration */
73 static int degraded = 0;	/* whether the FMRI has been marked degraded */
74 
75 /*
76  * This is needed for mech_krb5 -- we run as daemon, yes, but we want
77  * mech_krb5 to think we're root so it can get host/nodename.fqdn
78  * tickets for us so we can authenticate to AD as the machine account
79  * that we are.  For more details look at the entry point in mech_krb5
80  * corresponding to gss_init_sec_context().
81  *
82  * As a side effect of faking our effective UID to mech_krb5 we will use
83  * root's default ccache (/tmp/krb5cc_0).  But if that's created by
84  * another process then we won't have access to it: we run as daemon and
85  * keep PRIV_FILE_DAC_READ, which is insufficient to share the ccache
86  * with others.  We putenv("KRB5CCNAME=/var/run/idmap/ccache") in main()
87  * to avoid this issue; see main().
88  *
89  * Someday we'll have gss/mech_krb5 extensions for acquiring initiator
90  * creds with keytabs/raw keys, and someday we'll have extensions to
91  * libsasl to specify creds/name to use on the initiator side, and
92  * someday we'll have extensions to libldap to pass those through to
93  * libsasl.  Until then this interposer will have to do.
94  *
95  * Also, we have to tell lint to shut up: it thinks app_krb5_user_uid()
96  * is defined but not used.
97  */
98 /*LINTLIBRARY*/
99 uid_t
100 app_krb5_user_uid(void)
101 {
102 	return (0);
103 }
104 
105 /*ARGSUSED*/
106 static void
107 term_handler(int sig)
108 {
109 	idmapdlog(LOG_INFO, "Terminating.");
110 	fini_idmapd();
111 	_exit(0);
112 }
113 
114 /*ARGSUSED*/
115 static void
116 usr1_handler(int sig)
117 {
118 	bool_t saved_debug_mode = _idmapdstate.debug_mode;
119 
120 	_idmapdstate.debug_mode = TRUE;
121 	print_idmapdstate();
122 	_idmapdstate.debug_mode = saved_debug_mode;
123 }
124 
125 static int pipe_fd = -1;
126 
127 static void
128 daemonize_ready(void)
129 {
130 	char data = '\0';
131 	/*
132 	 * wake the parent
133 	 */
134 	(void) write(pipe_fd, &data, 1);
135 	(void) close(pipe_fd);
136 }
137 
138 static int
139 daemonize_start(void)
140 {
141 	char	data;
142 	int	status;
143 	int	devnull;
144 	int	filedes[2];
145 	pid_t	pid;
146 
147 	(void) sigset(SIGPIPE, SIG_IGN);
148 	devnull = open("/dev/null", O_RDONLY);
149 	if (devnull < 0)
150 		return (-1);
151 	(void) dup2(devnull, 0);
152 	(void) dup2(2, 1);	/* stderr only */
153 	if (pipe(filedes) < 0)
154 		return (-1);
155 	if ((pid = fork1()) < 0)
156 		return (-1);
157 	if (pid != 0) {
158 		/*
159 		 * parent
160 		 */
161 		(void) close(filedes[1]);
162 		if (read(filedes[0], &data, 1) == 1) {
163 			/* presume success */
164 			_exit(0);
165 		}
166 		status = -1;
167 		(void) wait4(pid, &status, 0, NULL);
168 		if (WIFEXITED(status))
169 			_exit(WEXITSTATUS(status));
170 		else
171 			_exit(-1);
172 	}
173 
174 	/*
175 	 * child
176 	 */
177 	pipe_fd = filedes[1];
178 	(void) close(filedes[0]);
179 	(void) setsid();
180 	(void) umask(0077);
181 	openlog("idmap", LOG_PID, LOG_DAEMON);
182 	return (0);
183 }
184 
185 
186 int
187 main(int argc, char **argv)
188 {
189 	int c;
190 	struct rlimit rl;
191 
192 	_idmapdstate.daemon_mode = TRUE;
193 	_idmapdstate.debug_mode = FALSE;
194 	while ((c = getopt(argc, argv, "d")) != -1) {
195 		switch (c) {
196 			case 'd':
197 				_idmapdstate.daemon_mode = FALSE;
198 				break;
199 			default:
200 				fprintf(stderr, "Usage: /usr/lib/idmapd");
201 				return (SMF_EXIT_ERR_CONFIG);
202 				break;
203 		}
204 	}
205 
206 	/* set locale and domain for internationalization */
207 	(void) setlocale(LC_ALL, "");
208 	(void) textdomain(TEXT_DOMAIN);
209 
210 	if (is_system_labeled() && getzoneid() != GLOBAL_ZONEID) {
211 		idmapdlog(LOG_ERR,
212 		    "with Trusted Extensions idmapd runs only in the "
213 		    "global zone");
214 		exit(1);
215 	}
216 
217 	/*
218 	 * Raise the fd limit to max
219 	 */
220 	if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
221 		idmapdlog(LOG_ERR, "getrlimit failed");
222 	} else if (rl.rlim_cur < rl.rlim_max) {
223 		rl.rlim_cur = rl.rlim_max;
224 		if (setrlimit(RLIMIT_NOFILE, &rl) != 0)
225 			idmapdlog(LOG_ERR,
226 			    "Unable to raise RLIMIT_NOFILE to %d",
227 			    rl.rlim_cur);
228 	}
229 
230 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
231 
232 	if (_idmapdstate.daemon_mode == TRUE) {
233 		if (daemonize_start() < 0) {
234 			(void) idmapdlog(LOG_ERR, "unable to daemonize");
235 			exit(-1);
236 		}
237 	} else
238 		(void) umask(0077);
239 
240 	idmap_init_tsd_key();
241 
242 	init_idmapd();
243 
244 	/* signal handlers that should run only after we're initialized */
245 	(void) sigset(SIGTERM, term_handler);
246 	(void) sigset(SIGUSR1, usr1_handler);
247 	(void) sigset(SIGHUP, idmap_cfg_hup_handler);
248 
249 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
250 	    DAEMON_UID, DAEMON_GID,
251 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
252 	    (char *)NULL) == -1) {
253 		idmapdlog(LOG_ERR, "unable to drop privileges");
254 		exit(1);
255 	}
256 
257 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
258 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
259 
260 	if (_idmapdstate.daemon_mode == TRUE)
261 		daemonize_ready();
262 
263 	/* With doors RPC this just wastes this thread, oh well */
264 	svc_run();
265 	return (0);
266 }
267 
268 static void
269 init_idmapd()
270 {
271 	int	error;
272 	int connmaxrec = IDMAP_MAX_DOOR_RPC;
273 
274 	/* create directories as root and chown to daemon uid */
275 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
276 		exit(1);
277 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
278 		exit(1);
279 
280 	/*
281 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
282 	 * for more details.  We blow away the existing one, if there is
283 	 * one.
284 	 */
285 	(void) unlink(IDMAP_CACHEDIR "/ccache");
286 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
287 
288 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
289 	    sizeof (_idmapdstate.hostname)) == -1) {
290 		error = errno;
291 		idmapdlog(LOG_ERR, "unable to determine hostname, error: %d",
292 		    error);
293 		exit(1);
294 	}
295 
296 	if ((error = init_mapping_system()) < 0) {
297 		idmapdlog(LOG_ERR, "unable to initialize mapping system");
298 		exit(error < -2 ? SMF_EXIT_ERR_CONFIG : 1);
299 	}
300 
301 	xprt = svc_door_create(idmap_prog_1, IDMAP_PROG, IDMAP_V1, connmaxrec);
302 	if (xprt == NULL) {
303 		idmapdlog(LOG_ERR, "unable to create door RPC service");
304 		goto errout;
305 	}
306 
307 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
308 		idmapdlog(LOG_ERR, "unable to limit RPC request size");
309 		goto errout;
310 	}
311 
312 	dfd = xprt->xp_fd;
313 
314 	if (dfd == -1) {
315 		idmapdlog(LOG_ERR, "unable to register door");
316 		goto errout;
317 	}
318 	if ((error = idmap_reg(dfd)) != 0) {
319 		idmapdlog(LOG_ERR, "unable to register door (%s)",
320 		    strerror(errno));
321 		goto errout;
322 	}
323 
324 	if ((error = allocids(_idmapdstate.new_eph_db,
325 	    8192, &_idmapdstate.next_uid,
326 	    8192, &_idmapdstate.next_gid)) != 0) {
327 		idmapdlog(LOG_ERR, "unable to allocate ephemeral IDs (%s)",
328 		    strerror(errno));
329 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
330 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
331 	} else {
332 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
333 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
334 	}
335 
336 	print_idmapdstate();
337 
338 	return;
339 
340 errout:
341 	fini_idmapd();
342 	exit(1);
343 }
344 
345 static void
346 fini_idmapd()
347 {
348 	idmap_unreg(dfd);
349 	fini_mapping_system();
350 	if (xprt != NULL)
351 		svc_destroy(xprt);
352 }
353 
354 static
355 const char *
356 get_fmri(void)
357 {
358 	static char *fmri = NULL;
359 	static char buf[60];
360 	char *s;
361 
362 	membar_consumer();
363 	s = fmri;
364 	if (s != NULL && *s == '\0')
365 		return (NULL);
366 	else if (s != NULL)
367 		return (s);
368 
369 	if ((s = getenv("SMF_FMRI")) == NULL || strlen(s) >= sizeof (buf))
370 		buf[0] = '\0';
371 	else
372 		(void) strlcpy(buf, s, sizeof (buf));
373 
374 	membar_producer();
375 	fmri = buf;
376 
377 	return (get_fmri());
378 }
379 
380 /*
381  * Wrappers for smf_degrade/restore_instance()
382  *
383  * smf_restore_instance() is too heavy duty to be calling every time we
384  * have a successful AD name<->SID lookup.
385  */
386 void
387 degrade_svc(int poke_discovery, const char *reason)
388 {
389 	const char *fmri;
390 
391 	/*
392 	 * If the config update thread is in a state where auto-discovery could
393 	 * be re-tried, then this will make it try it -- a sort of auto-refresh.
394 	 */
395 	if (poke_discovery)
396 		idmap_cfg_poke_updates();
397 
398 	membar_consumer();
399 	if (degraded)
400 		return;
401 
402 	idmapdlog(LOG_ERR, "Degraded operation (%s).  If you are running an "
403 	    "SMB server in workgroup mode, or if you're not running an SMB "
404 	    "server, then you can ignore this message", reason);
405 
406 	membar_producer();
407 	degraded = 1;
408 
409 	if ((fmri = get_fmri()) != NULL)
410 		(void) smf_degrade_instance(fmri, 0);
411 }
412 
413 void
414 restore_svc(void)
415 {
416 	const char *fmri;
417 
418 	membar_consumer();
419 	if (!degraded)
420 		return;
421 
422 	if ((fmri = get_fmri()) == NULL)
423 		(void) smf_restore_instance(fmri);
424 
425 	membar_producer();
426 	degraded = 0;
427 	idmapdlog(LOG_NOTICE, "Normal operation restored");
428 }
429 
430 void
431 idmapdlog(int pri, const char *format, ...)
432 {
433 	va_list args;
434 
435 	va_start(args, format);
436 
437 	if (_idmapdstate.debug_mode == TRUE ||
438 	    _idmapdstate.daemon_mode == FALSE) {
439 		(void) vfprintf(stderr, format, args);
440 		(void) fprintf(stderr, "\n");
441 	}
442 
443 	/*
444 	 * We don't want to fill up the logs with useless messages when
445 	 * we're degraded, but we still want to log.
446 	 */
447 	if (degraded)
448 		pri = LOG_DEBUG;
449 
450 	(void) vsyslog(pri, format, args);
451 	va_end(args);
452 }
453