xref: /illumos-gate/usr/src/cmd/idmap/idmapd/idmapd.c (revision 8e228215)
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 2007 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 <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 <syslog.h>
43 #include <rpcsvc/daemon_utils.h> /* DAEMON_UID and DAEMON_GID */
44 #include <priv_utils.h> /* privileges */
45 #include <locale.h>
46 #include <sys/systeminfo.h>
47 #include <errno.h>
48 #include <sys/wait.h>
49 #include <sys/time.h>
50 #include <zone.h>
51 #include <door.h>
52 #include <tsol/label.h>
53 #include <sys/resource.h>
54 #include <sys/sid.h>
55 #include <sys/idmap.h>
56 
57 static void	hup_handler(int);
58 static void	term_handler(int);
59 static void	init_idmapd();
60 static void	fini_idmapd();
61 
62 #ifndef SIG_PF
63 #define	SIG_PF void(*)(int)
64 #endif
65 
66 #define	_RPCSVC_CLOSEDOWN 120
67 
68 int _rpcsvcstate = _IDLE;	/* Set when a request is serviced */
69 int _rpcsvccount = 0;		/* Number of requests being serviced */
70 mutex_t _svcstate_lock;		/* lock for _rpcsvcstate, _rpcsvccount */
71 idmapd_state_t	_idmapdstate;
72 
73 SVCXPRT *xprt = NULL;
74 
75 static int dfd = -1;		/* our door server fildes, for unregistration */
76 
77 #ifdef DEBUG
78 #define	RPC_SVC_FG
79 #endif
80 
81 /*
82  * This is needed for mech_krb5 -- we run as daemon, yes, but we want
83  * mech_krb5 to think we're root so it can get host/nodename.fqdn
84  * tickets for us so we can authenticate to AD as the machine account
85  * that we are.  For more details look at the entry point in mech_krb5
86  * corresponding to gss_init_sec_context().
87  *
88  * As a side effect of faking our effective UID to mech_krb5 we will use
89  * root's default ccache (/tmp/krb5cc_0).  But if that's created by
90  * another process then we won't have access to it: we run as daemon and
91  * keep PRIV_FILE_DAC_READ, which is insufficient to share the ccache
92  * with others.  We putenv("KRB5CCNAME=/var/run/idmap/ccache") in main()
93  * to avoid this issue; see main().
94  *
95  * Someday we'll have gss/mech_krb5 extensions for acquiring initiator
96  * creds with keytabs/raw keys, and someday we'll have extensions to
97  * libsasl to specify creds/name to use on the initiator side, and
98  * someday we'll have extensions to libldap to pass those through to
99  * libsasl.  Until then this interposer will have to do.
100  *
101  * Also, we have to tell lint to shut up: it thinks app_krb5_user_uid()
102  * is defined but not used.
103  */
104 /*LINTLIBRARY*/
105 uid_t
106 app_krb5_user_uid(void)
107 {
108 	return (0);
109 }
110 
111 /*ARGSUSED*/
112 static void
113 hup_handler(int sig) {
114 	(void) idmapdlog(LOG_INFO, "idmapd: Refreshing config.");
115 	WRLOCK_CONFIG();
116 	(void) idmap_cfg_fini(_idmapdstate.cfg);
117 	_idmapdstate.cfg = NULL;
118 	if (load_config() < 0) {
119 		UNLOCK_CONFIG();
120 		(void) idmapdlog(LOG_NOTICE,
121 			"idmapd: Failed to reload config");
122 		term_handler(sig);
123 	}
124 	UNLOCK_CONFIG();
125 	print_idmapdstate();
126 }
127 
128 /*ARGSUSED*/
129 static void
130 term_handler(int sig) {
131 	(void) idmapdlog(LOG_INFO, "idmapd: Terminating.");
132 	fini_idmapd();
133 	_exit(0);
134 }
135 
136 static int pipe_fd = -1;
137 
138 static void
139 daemonize_ready(void) {
140 	char data = '\0';
141 	/*
142 	 * wake the parent
143 	 */
144 	(void) write(pipe_fd, &data, 1);
145 	(void) close(pipe_fd);
146 }
147 
148 static int
149 daemonize_start(void) {
150 	char	data;
151 	int	status;
152 	int	devnull;
153 	int	filedes[2];
154 	pid_t	pid;
155 
156 	(void) sigset(SIGPIPE, SIG_IGN);
157 	devnull = open("/dev/null", O_RDONLY);
158 	if (devnull < 0)
159 		return (-1);
160 	(void) dup2(devnull, 0);
161 	(void) dup2(2, 1);	/* stderr only */
162 	if (pipe(filedes) < 0)
163 		return (-1);
164 	if ((pid = fork1()) < 0)
165 		return (-1);
166 	if (pid != 0) {
167 		/*
168 		 * parent
169 		 */
170 		(void) close(filedes[1]);
171 		if (read(filedes[0], &data, 1) == 1) {
172 			/* presume success */
173 			_exit(0);
174 		}
175 		status = -1;
176 		(void) wait4(pid, &status, 0, NULL);
177 		if (WIFEXITED(status))
178 			_exit(WEXITSTATUS(status));
179 		else
180 			_exit(-1);
181 	}
182 
183 	/*
184 	 * child
185 	 */
186 	pipe_fd = filedes[1];
187 	(void) close(filedes[0]);
188 	(void) setsid();
189 	(void) umask(0077);
190 	openlog("idmap", LOG_PID, LOG_DAEMON);
191 	_idmapdstate.daemon_mode = TRUE;
192 	return (0);
193 }
194 
195 
196 int
197 main(int argc, char **argv)
198 {
199 	int c;
200 #ifdef RPC_SVC_FG
201 	bool_t daemonize = FALSE;
202 #else
203 	bool_t daemonize = TRUE;
204 #endif
205 
206 	while ((c = getopt(argc, argv, "d")) != EOF) {
207 		switch (c) {
208 			case 'd':
209 				daemonize = FALSE;
210 				break;
211 			default:
212 				break;
213 		}
214 	}
215 
216 	/* set locale and domain for internationalization */
217 	(void) setlocale(LC_ALL, "");
218 	(void) textdomain(TEXT_DOMAIN);
219 
220 	if (getzoneid() != GLOBAL_ZONEID) {
221 		(void) idmapdlog(LOG_ERR,
222 		    "idmapd: idmapd runs only in the global zone");
223 		exit(1);
224 	}
225 
226 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
227 
228 	if (daemonize == TRUE) {
229 		if (daemonize_start() < 0) {
230 			(void) perror("idmapd: unable to daemonize");
231 			exit(-1);
232 		}
233 	} else
234 		(void) umask(0077);
235 
236 	idmap_init_tsd_key();
237 
238 	init_idmapd();
239 
240 	/* signal handlers that should run only after we're initialized */
241 	(void) sigset(SIGTERM, term_handler);
242 	(void) sigset(SIGHUP, hup_handler);
243 
244 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
245 	    DAEMON_UID, DAEMON_GID,
246 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
247 	    (char *)NULL) == -1) {
248 		(void) idmapdlog(LOG_ERR, "idmapd: unable to drop privileges");
249 		exit(1);
250 	}
251 
252 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
253 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
254 
255 	if (daemonize == TRUE)
256 		daemonize_ready();
257 
258 	/* With doors RPC this just wastes this thread, oh well */
259 	svc_run();
260 	return (0);
261 }
262 
263 static void
264 init_idmapd() {
265 	int	error;
266 	int connmaxrec = RPC_MAX_SIZE;
267 
268 	/* create directories as root and chown to daemon uid */
269 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
270 		exit(1);
271 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
272 		exit(1);
273 
274 	/*
275 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
276 	 * for more details.
277 	 */
278 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
279 
280 	memset(&_idmapdstate, 0, sizeof (_idmapdstate));
281 
282 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
283 			sizeof (_idmapdstate.hostname)) == -1) {
284 		error = errno;
285 		idmapdlog(LOG_ERR,
286 	"idmapd: unable to determine hostname, error: %d",
287 			error);
288 		exit(1);
289 	}
290 
291 	if (sysinfo(SI_SRPC_DOMAIN, _idmapdstate.domainname,
292 			sizeof (_idmapdstate.domainname)) == -1) {
293 		error = errno;
294 		idmapdlog(LOG_ERR,
295 	"idmapd: unable to determine name service domain, error: %d",
296 			error);
297 		exit(1);
298 	}
299 
300 	if (init_mapping_system() < 0) {
301 		idmapdlog(LOG_ERR,
302 		"idmapd: unable to initialize mapping system");
303 		exit(1);
304 	}
305 
306 	xprt = svc_door_create(idmap_prog_1, IDMAP_PROG, IDMAP_V1, 0);
307 	if (xprt == NULL) {
308 		idmapdlog(LOG_ERR,
309 		"idmapd: unable to create door RPC service");
310 		goto errout;
311 	}
312 
313 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
314 		idmapdlog(LOG_ERR,
315 		    "idmapd: unable to limit RPC request size");
316 		goto errout;
317 	}
318 
319 	dfd = xprt->xp_fd;
320 
321 	if (dfd == -1) {
322 		idmapdlog(LOG_ERR, "idmapd: unable to register door");
323 		goto errout;
324 	}
325 	if ((error = idmap_reg(dfd)) != 0) {
326 		idmapdlog(LOG_ERR, "idmapd: unable to register door (%s)",
327 				strerror(error));
328 		goto errout;
329 	}
330 
331 	if ((error = allocids(_idmapdstate.new_eph_db,
332 			8192, &_idmapdstate.next_uid,
333 			8192, &_idmapdstate.next_gid)) != 0) {
334 		idmapdlog(LOG_ERR, "idmapd: unable to allocate ephemeral IDs "
335 			"(%s)", strerror(error));
336 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
337 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
338 	} else {
339 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
340 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
341 	}
342 
343 	print_idmapdstate();
344 
345 	return;
346 
347 errout:
348 	fini_idmapd();
349 	exit(1);
350 }
351 
352 static void
353 fini_idmapd() {
354 	idmap_unreg(dfd);
355 	fini_mapping_system();
356 	if (xprt != NULL)
357 		svc_destroy(xprt);
358 }
359 
360 void
361 idmapdlog(int pri, const char *format, ...) {
362 	va_list args;
363 
364 	va_start(args, format);
365 	if (_idmapdstate.daemon_mode == FALSE) {
366 		(void) vfprintf(stderr, format, args);
367 		(void) fprintf(stderr, "\n");
368 	}
369 	(void) vsyslog(pri, format, args);
370 	va_end(args);
371 }
372