xref: /illumos-gate/usr/src/cmd/idmap/idmapd/idmapd.c (revision d4517e84e3ffaa7bc4207a17f694c309904e7c48)
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	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 term_handler(int sig)
114 {
115 	(void) idmapdlog(LOG_INFO, "idmapd: Terminating.");
116 	fini_idmapd();
117 	_exit(0);
118 }
119 
120 static int pipe_fd = -1;
121 
122 static void
123 daemonize_ready(void)
124 {
125 	char data = '\0';
126 	/*
127 	 * wake the parent
128 	 */
129 	(void) write(pipe_fd, &data, 1);
130 	(void) close(pipe_fd);
131 }
132 
133 static int
134 daemonize_start(void)
135 {
136 	char	data;
137 	int	status;
138 	int	devnull;
139 	int	filedes[2];
140 	pid_t	pid;
141 
142 	(void) sigset(SIGPIPE, SIG_IGN);
143 	devnull = open("/dev/null", O_RDONLY);
144 	if (devnull < 0)
145 		return (-1);
146 	(void) dup2(devnull, 0);
147 	(void) dup2(2, 1);	/* stderr only */
148 	if (pipe(filedes) < 0)
149 		return (-1);
150 	if ((pid = fork1()) < 0)
151 		return (-1);
152 	if (pid != 0) {
153 		/*
154 		 * parent
155 		 */
156 		(void) close(filedes[1]);
157 		if (read(filedes[0], &data, 1) == 1) {
158 			/* presume success */
159 			_exit(0);
160 		}
161 		status = -1;
162 		(void) wait4(pid, &status, 0, NULL);
163 		if (WIFEXITED(status))
164 			_exit(WEXITSTATUS(status));
165 		else
166 			_exit(-1);
167 	}
168 
169 	/*
170 	 * child
171 	 */
172 	pipe_fd = filedes[1];
173 	(void) close(filedes[0]);
174 	(void) setsid();
175 	(void) umask(0077);
176 	openlog("idmap", LOG_PID, LOG_DAEMON);
177 	_idmapdstate.daemon_mode = TRUE;
178 	return (0);
179 }
180 
181 
182 int
183 main(int argc, char **argv)
184 {
185 	int c;
186 #ifdef RPC_SVC_FG
187 	bool_t daemonize = FALSE;
188 #else
189 	bool_t daemonize = TRUE;
190 #endif
191 
192 	while ((c = getopt(argc, argv, "d")) != EOF) {
193 		switch (c) {
194 			case 'd':
195 				daemonize = FALSE;
196 				break;
197 			default:
198 				break;
199 		}
200 	}
201 
202 	/* set locale and domain for internationalization */
203 	(void) setlocale(LC_ALL, "");
204 	(void) textdomain(TEXT_DOMAIN);
205 
206 	if (is_system_labeled() && getzoneid() != GLOBAL_ZONEID) {
207 		(void) idmapdlog(LOG_ERR,
208 		    "idmapd: with Trusted Extensions idmapd runs only in the "
209 		    "global zone");
210 		exit(1);
211 	}
212 
213 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
214 
215 	if (daemonize == TRUE) {
216 		if (daemonize_start() < 0) {
217 			(void) perror("idmapd: unable to daemonize");
218 			exit(-1);
219 		}
220 	} else
221 		(void) umask(0077);
222 
223 	idmap_init_tsd_key();
224 
225 	init_idmapd();
226 
227 	/* signal handlers that should run only after we're initialized */
228 	(void) sigset(SIGTERM, term_handler);
229 	(void) sigset(SIGHUP, idmap_cfg_hup_handler);
230 
231 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
232 	    DAEMON_UID, DAEMON_GID,
233 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
234 	    (char *)NULL) == -1) {
235 		(void) idmapdlog(LOG_ERR, "idmapd: unable to drop privileges");
236 		exit(1);
237 	}
238 
239 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
240 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
241 
242 	if (daemonize == TRUE)
243 		daemonize_ready();
244 
245 	/* With doors RPC this just wastes this thread, oh well */
246 	svc_run();
247 	return (0);
248 }
249 
250 static void
251 init_idmapd()
252 {
253 	int	error;
254 	int connmaxrec = IDMAP_MAX_DOOR_RPC;
255 
256 	/* create directories as root and chown to daemon uid */
257 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
258 		exit(1);
259 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
260 		exit(1);
261 
262 	/*
263 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
264 	 * for more details.  We blow away the existing one, if there is
265 	 * one.
266 	 */
267 	(void) unlink(IDMAP_CACHEDIR "/ccache");
268 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
269 
270 	memset(&_idmapdstate, 0, sizeof (_idmapdstate));
271 
272 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
273 	    sizeof (_idmapdstate.hostname)) == -1) {
274 		error = errno;
275 		idmapdlog(LOG_ERR,
276 		    "idmapd: unable to determine hostname, error: %d",
277 		    error);
278 		exit(1);
279 	}
280 
281 	if ((error = init_mapping_system()) < 0) {
282 		idmapdlog(LOG_ERR,
283 		    "idmapd: unable to initialize mapping system");
284 		exit(error < -2 ? SMF_EXIT_ERR_CONFIG : 1);
285 	}
286 
287 	xprt = svc_door_create(idmap_prog_1, IDMAP_PROG, IDMAP_V1, connmaxrec);
288 	if (xprt == NULL) {
289 		idmapdlog(LOG_ERR,
290 		    "idmapd: unable to create door RPC service");
291 		goto errout;
292 	}
293 
294 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
295 		idmapdlog(LOG_ERR,
296 		    "idmapd: unable to limit RPC request size");
297 		goto errout;
298 	}
299 
300 	dfd = xprt->xp_fd;
301 
302 	if (dfd == -1) {
303 		idmapdlog(LOG_ERR, "idmapd: unable to register door");
304 		goto errout;
305 	}
306 	if ((error = idmap_reg(dfd)) != 0) {
307 		idmapdlog(LOG_ERR, "idmapd: unable to register door (%s)",
308 		    strerror(errno));
309 		goto errout;
310 	}
311 
312 	if ((error = allocids(_idmapdstate.new_eph_db,
313 	    8192, &_idmapdstate.next_uid,
314 	    8192, &_idmapdstate.next_gid)) != 0) {
315 		idmapdlog(LOG_ERR, "idmapd: unable to allocate ephemeral IDs "
316 		    "(%s)", strerror(errno));
317 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
318 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
319 	} else {
320 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
321 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
322 	}
323 
324 	print_idmapdstate();
325 
326 	return;
327 
328 errout:
329 	fini_idmapd();
330 	exit(1);
331 }
332 
333 static void
334 fini_idmapd()
335 {
336 	idmap_unreg(dfd);
337 	fini_mapping_system();
338 	if (xprt != NULL)
339 		svc_destroy(xprt);
340 }
341 
342 void
343 idmapdlog(int pri, const char *format, ...)
344 {
345 	va_list args;
346 
347 	va_start(args, format);
348 	if (_idmapdstate.daemon_mode == FALSE) {
349 		(void) vfprintf(stderr, format, args);
350 		(void) fprintf(stderr, "\n");
351 	}
352 	(void) vsyslog(pri, format, args);
353 	va_end(args);
354 }
355