xref: /titanic_52/usr/src/cmd/idmap/idmapd/idmapd.c (revision 36e5aa2ab5c51d4747a2470e41ccb782056c90e7)
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 <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 	hupped = 1;
119 	if (hup_ev_port >= 0)
120 		(void) port_send(hup_ev_port, 1, &sig /* any ptr will do */);
121 }
122 
123 
124 /*ARGSUSED*/
125 static void
126 term_handler(int sig) {
127 	(void) idmapdlog(LOG_INFO, "idmapd: Terminating.");
128 	fini_idmapd();
129 	_exit(0);
130 }
131 
132 static int pipe_fd = -1;
133 
134 static void
135 daemonize_ready(void) {
136 	char data = '\0';
137 	/*
138 	 * wake the parent
139 	 */
140 	(void) write(pipe_fd, &data, 1);
141 	(void) close(pipe_fd);
142 }
143 
144 static int
145 daemonize_start(void) {
146 	char	data;
147 	int	status;
148 	int	devnull;
149 	int	filedes[2];
150 	pid_t	pid;
151 
152 	(void) sigset(SIGPIPE, SIG_IGN);
153 	devnull = open("/dev/null", O_RDONLY);
154 	if (devnull < 0)
155 		return (-1);
156 	(void) dup2(devnull, 0);
157 	(void) dup2(2, 1);	/* stderr only */
158 	if (pipe(filedes) < 0)
159 		return (-1);
160 	if ((pid = fork1()) < 0)
161 		return (-1);
162 	if (pid != 0) {
163 		/*
164 		 * parent
165 		 */
166 		(void) close(filedes[1]);
167 		if (read(filedes[0], &data, 1) == 1) {
168 			/* presume success */
169 			_exit(0);
170 		}
171 		status = -1;
172 		(void) wait4(pid, &status, 0, NULL);
173 		if (WIFEXITED(status))
174 			_exit(WEXITSTATUS(status));
175 		else
176 			_exit(-1);
177 	}
178 
179 	/*
180 	 * child
181 	 */
182 	pipe_fd = filedes[1];
183 	(void) close(filedes[0]);
184 	(void) setsid();
185 	(void) umask(0077);
186 	openlog("idmap", LOG_PID, LOG_DAEMON);
187 	_idmapdstate.daemon_mode = TRUE;
188 	return (0);
189 }
190 
191 
192 int
193 main(int argc, char **argv)
194 {
195 	int c;
196 #ifdef RPC_SVC_FG
197 	bool_t daemonize = FALSE;
198 #else
199 	bool_t daemonize = TRUE;
200 #endif
201 
202 	while ((c = getopt(argc, argv, "d")) != EOF) {
203 		switch (c) {
204 			case 'd':
205 				daemonize = FALSE;
206 				break;
207 			default:
208 				break;
209 		}
210 	}
211 
212 	/* set locale and domain for internationalization */
213 	(void) setlocale(LC_ALL, "");
214 	(void) textdomain(TEXT_DOMAIN);
215 
216 	if (getzoneid() != GLOBAL_ZONEID) {
217 		(void) idmapdlog(LOG_ERR,
218 		    "idmapd: idmapd runs only in the global zone");
219 		exit(1);
220 	}
221 
222 	(void) mutex_init(&_svcstate_lock, USYNC_THREAD, NULL);
223 
224 	if (daemonize == TRUE) {
225 		if (daemonize_start() < 0) {
226 			(void) perror("idmapd: unable to daemonize");
227 			exit(-1);
228 		}
229 	} else
230 		(void) umask(0077);
231 
232 	idmap_init_tsd_key();
233 
234 	init_idmapd();
235 
236 	/* signal handlers that should run only after we're initialized */
237 	(void) sigset(SIGTERM, term_handler);
238 	(void) sigset(SIGHUP, hup_handler);
239 
240 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
241 	    DAEMON_UID, DAEMON_GID,
242 	    PRIV_PROC_AUDIT, PRIV_FILE_DAC_READ,
243 	    (char *)NULL) == -1) {
244 		(void) idmapdlog(LOG_ERR, "idmapd: unable to drop privileges");
245 		exit(1);
246 	}
247 
248 	__fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
249 	    PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);
250 
251 	if (daemonize == TRUE)
252 		daemonize_ready();
253 
254 	/* With doors RPC this just wastes this thread, oh well */
255 	svc_run();
256 	return (0);
257 }
258 
259 static void
260 init_idmapd() {
261 	int	error;
262 	int connmaxrec = IDMAP_MAX_DOOR_RPC;
263 
264 	/* create directories as root and chown to daemon uid */
265 	if (create_directory(IDMAP_DBDIR, DAEMON_UID, DAEMON_GID) < 0)
266 		exit(1);
267 	if (create_directory(IDMAP_CACHEDIR, DAEMON_UID, DAEMON_GID) < 0)
268 		exit(1);
269 
270 	/*
271 	 * Set KRB5CCNAME in the environment.  See app_krb5_user_uid()
272 	 * for more details.  We blow away the existing one, if there is
273 	 * one.
274 	 */
275 	(void) unlink(IDMAP_CACHEDIR "/ccache");
276 	putenv("KRB5CCNAME=" IDMAP_CACHEDIR "/ccache");
277 
278 	memset(&_idmapdstate, 0, sizeof (_idmapdstate));
279 
280 	if (sysinfo(SI_HOSTNAME, _idmapdstate.hostname,
281 			sizeof (_idmapdstate.hostname)) == -1) {
282 		error = errno;
283 		idmapdlog(LOG_ERR,
284 	"idmapd: unable to determine hostname, error: %d",
285 			error);
286 		exit(1);
287 	}
288 
289 	if (init_mapping_system() < 0) {
290 		idmapdlog(LOG_ERR,
291 		"idmapd: unable to initialize mapping system");
292 		exit(1);
293 	}
294 
295 	xprt = svc_door_create(idmap_prog_1, IDMAP_PROG, IDMAP_V1, connmaxrec);
296 	if (xprt == NULL) {
297 		idmapdlog(LOG_ERR,
298 		"idmapd: unable to create door RPC service");
299 		goto errout;
300 	}
301 
302 	if (!svc_control(xprt, SVCSET_CONNMAXREC, &connmaxrec)) {
303 		idmapdlog(LOG_ERR,
304 		    "idmapd: unable to limit RPC request size");
305 		goto errout;
306 	}
307 
308 	dfd = xprt->xp_fd;
309 
310 	if (dfd == -1) {
311 		idmapdlog(LOG_ERR, "idmapd: unable to register door");
312 		goto errout;
313 	}
314 	if ((error = idmap_reg(dfd)) != 0) {
315 		idmapdlog(LOG_ERR, "idmapd: unable to register door (%s)",
316 				strerror(error));
317 		goto errout;
318 	}
319 
320 	if ((error = allocids(_idmapdstate.new_eph_db,
321 			8192, &_idmapdstate.next_uid,
322 			8192, &_idmapdstate.next_gid)) != 0) {
323 		idmapdlog(LOG_ERR, "idmapd: unable to allocate ephemeral IDs "
324 			"(%s)", strerror(error));
325 		_idmapdstate.next_uid = _idmapdstate.limit_uid = SENTINEL_PID;
326 		_idmapdstate.next_gid = _idmapdstate.limit_gid = SENTINEL_PID;
327 	} else {
328 		_idmapdstate.limit_uid = _idmapdstate.next_uid + 8192;
329 		_idmapdstate.limit_gid = _idmapdstate.next_gid + 8192;
330 	}
331 
332 	print_idmapdstate();
333 
334 	return;
335 
336 errout:
337 	fini_idmapd();
338 	exit(1);
339 }
340 
341 static void
342 fini_idmapd() {
343 	idmap_unreg(dfd);
344 	fini_mapping_system();
345 	if (xprt != NULL)
346 		svc_destroy(xprt);
347 }
348 
349 void
350 idmapdlog(int pri, const char *format, ...) {
351 	va_list args;
352 
353 	va_start(args, format);
354 	if (_idmapdstate.daemon_mode == FALSE) {
355 		(void) vfprintf(stderr, format, args);
356 		(void) fprintf(stderr, "\n");
357 	}
358 	(void) vsyslog(pri, format, args);
359 	va_end(args);
360 }
361