xref: /illumos-gate/usr/src/cmd/idmap/idmapd/idmapd.c (revision 4edd44c5)
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 <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 <port.h>
53 #include <tsol/label.h>
54 #include <sys/resource.h>
55 #include <sys/sid.h>
56 #include <sys/idmap.h>
57 
58 static void	hup_handler(int);
59 static void	term_handler(int);
60 static void	init_idmapd();
61 static void	fini_idmapd();
62 
63 #ifndef SIG_PF
64 #define	SIG_PF void(*)(int)
65 #endif
66 
67 #define	_RPCSVC_CLOSEDOWN 120
68 
69 int _rpcsvcstate = _IDLE;	/* Set when a request is serviced */
70 int _rpcsvccount = 0;		/* Number of requests being serviced */
71 mutex_t _svcstate_lock;		/* lock for _rpcsvcstate, _rpcsvccount */
72 idmapd_state_t	_idmapdstate;
73 
74 int hupped;
75 extern int hup_ev_port;
76 
77 SVCXPRT *xprt = NULL;
78 
79 static int dfd = -1;		/* our door server fildes, for unregistration */
80 
81 #ifdef DEBUG
82 #define	RPC_SVC_FG
83 #endif
84 
85 /*
86  * This is needed for mech_krb5 -- we run as daemon, yes, but we want
87  * mech_krb5 to think we're root so it can get host/nodename.fqdn
88  * tickets for us so we can authenticate to AD as the machine account
89  * that we are.  For more details look at the entry point in mech_krb5
90  * corresponding to gss_init_sec_context().
91  *
92  * As a side effect of faking our effective UID to mech_krb5 we will use
93  * root's default ccache (/tmp/krb5cc_0).  But if that's created by
94  * another process then we won't have access to it: we run as daemon and
95  * keep PRIV_FILE_DAC_READ, which is insufficient to share the ccache
96  * with others.  We putenv("KRB5CCNAME=/var/run/idmap/ccache") in main()
97  * to avoid this issue; see main().
98  *
99  * Someday we'll have gss/mech_krb5 extensions for acquiring initiator
100  * creds with keytabs/raw keys, and someday we'll have extensions to
101  * libsasl to specify creds/name to use on the initiator side, and
102  * someday we'll have extensions to libldap to pass those through to
103  * libsasl.  Until then this interposer will have to do.
104  *
105  * Also, we have to tell lint to shut up: it thinks app_krb5_user_uid()
106  * is defined but not used.
107  */
108 /*LINTLIBRARY*/
109 uid_t
110 app_krb5_user_uid(void)
111 {
112 	return (0);
113 }
114 
115 /*ARGSUSED*/
116 static void
117 hup_handler(int sig)
118 {
119 	hupped = 1;
120 	if (hup_ev_port >= 0)
121 		(void) port_send(hup_ev_port, 1, &sig /* any ptr will do */);
122 }
123 
124 
125 /*ARGSUSED*/
126 static void
127 term_handler(int sig)
128 {
129 	(void) idmapdlog(LOG_INFO, "idmapd: Terminating.");
130 	fini_idmapd();
131 	_exit(0);
132 }
133 
134 static int pipe_fd = -1;
135 
136 static void
137 daemonize_ready(void)
138 {
139 	char data = '\0';
140 	/*
141 	 * wake the parent
142 	 */
143 	(void) write(pipe_fd, &data, 1);
144 	(void) close(pipe_fd);
145 }
146 
147 static int
148 daemonize_start(void)
149 {
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 (is_system_labeled() && getzoneid() != GLOBAL_ZONEID) {
221 		(void) idmapdlog(LOG_ERR,
222 		    "idmapd: with Trusted Extensions idmapd runs only in the "
223 		    "global zone");
224 		exit(1);
225 	}
226 
227 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
228 
229 	if (daemonize == TRUE) {
230 		if (daemonize_start() < 0) {
231 			(void) perror("idmapd: unable to daemonize");
232 			exit(-1);
233 		}
234 	} else
235 		(void) umask(0077);
236 
237 	idmap_init_tsd_key();
238 
239 	init_idmapd();
240 
241 	/* signal handlers that should run only after we're initialized */
242 	(void) sigset(SIGTERM, term_handler);
243 	(void) sigset(SIGHUP, hup_handler);
244 
245 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
246 	    DAEMON_UID, DAEMON_GID,
247 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
248 	    (char *)NULL) == -1) {
249 		(void) idmapdlog(LOG_ERR, "idmapd: unable to drop privileges");
250 		exit(1);
251 	}
252 
253 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
254 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
255 
256 	if (daemonize == TRUE)
257 		daemonize_ready();
258 
259 	/* With doors RPC this just wastes this thread, oh well */
260 	svc_run();
261 	return (0);
262 }
263 
264 static void
265 init_idmapd()
266 {
267 	int	error;
268 	int connmaxrec = IDMAP_MAX_DOOR_RPC;
269 
270 	/* create directories as root and chown to daemon uid */
271 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
272 		exit(1);
273 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
274 		exit(1);
275 
276 	/*
277 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
278 	 * for more details.  We blow away the existing one, if there is
279 	 * one.
280 	 */
281 	(void) unlink(IDMAP_CACHEDIR "/ccache");
282 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
283 
284 	memset(&_idmapdstate, 0, sizeof (_idmapdstate));
285 
286 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
287 	    sizeof (_idmapdstate.hostname)) == -1) {
288 		error = errno;
289 		idmapdlog(LOG_ERR,
290 		    "idmapd: unable to determine hostname, error: %d",
291 		    error);
292 		exit(1);
293 	}
294 
295 	if ((error = init_mapping_system()) < 0) {
296 		idmapdlog(LOG_ERR,
297 		    "idmapd: 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,
304 		    "idmapd: unable to create door RPC service");
305 		goto errout;
306 	}
307 
308 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
309 		idmapdlog(LOG_ERR,
310 		    "idmapd: unable to limit RPC request size");
311 		goto errout;
312 	}
313 
314 	dfd = xprt->xp_fd;
315 
316 	if (dfd == -1) {
317 		idmapdlog(LOG_ERR, "idmapd: unable to register door");
318 		goto errout;
319 	}
320 	if ((error = idmap_reg(dfd)) != 0) {
321 		idmapdlog(LOG_ERR, "idmapd: unable to register door (%s)",
322 		    strerror(errno));
323 		goto errout;
324 	}
325 
326 	if ((error = allocids(_idmapdstate.new_eph_db,
327 	    8192, &_idmapdstate.next_uid,
328 	    8192, &_idmapdstate.next_gid)) != 0) {
329 		idmapdlog(LOG_ERR, "idmapd: unable to allocate ephemeral IDs "
330 		    "(%s)", strerror(errno));
331 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
332 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
333 	} else {
334 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
335 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
336 	}
337 
338 	print_idmapdstate();
339 
340 	return;
341 
342 errout:
343 	fini_idmapd();
344 	exit(1);
345 }
346 
347 static void
348 fini_idmapd()
349 {
350 	idmap_unreg(dfd);
351 	fini_mapping_system();
352 	if (xprt != NULL)
353 		svc_destroy(xprt);
354 }
355 
356 void
357 idmapdlog(int pri, const char *format, ...)
358 {
359 	va_list args;
360 
361 	va_start(args, format);
362 	if (_idmapdstate.daemon_mode == FALSE) {
363 		(void) vfprintf(stderr, format, args);
364 		(void) fprintf(stderr, "\n");
365 	}
366 	(void) vsyslog(pri, format, args);
367 	va_end(args);
368 }
369