xref: /titanic_52/usr/src/cmd/cmd-inet/lib/ipmgmtd/ipmgmt_main.c (revision e0724c534a46ca4754330bc022bf1e2a68f5bb93)
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 /*
23  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 /*
27  * The ipmgmtd daemon is started by ip-interface-management SMF service. This
28  * daemon is used to manage, mapping of 'address object' to 'interface name' and
29  * 'logical interface number', on which the address is created. It also provides
30  * a means to update the ipadm persistent data-store.
31  *
32  * The daemon tracks the <addrobj, lifname> mapping in-memory using a linked
33  * list `aobjmap'. Access to this list is synchronized using a readers-writers
34  * lock. The active <addrobj, lifname> mapping is kept in
35  * /etc/svc/volatile/ipadm/aobjmap.conf cache file, so that the mapping can be
36  * recovered when ipmgmtd exits for some reason (e.g., when ipmgmtd is restarted
37  * using svcadm or accidentally killed).
38  *
39  * Today, the persistent configuration of interfaces, addresses and protocol
40  * properties is kept in /etc/ipadm/ipadm.conf. The access to the persistent
41  * data store is synchronized using reader-writers lock `ipmgmt_dbconf_lock'.
42  *
43  * The communication between the library, libipadm.so and the daemon, is through
44  * doors RPC. The library interacts with the daemon using the commands defined
45  * by `ipmgmt_door_cmd_type_t'. Further any 'write' operation would require
46  * the `NETWORK_INTERFACE_CONFIG_AUTH' authorization.
47  *
48  * On reboot, the aforementioned SMF service starts the daemon before any other
49  * networking service that configures network IP interfaces is started.
50  * Afterwards, the network/physical SMF script instantiates the persisted
51  * network interfaces, interface properties and addresses.
52  */
53 
54 #include <errno.h>
55 #include <fcntl.h>
56 #include <priv_utils.h>
57 #include <signal.h>
58 #include <stdlib.h>
59 #include <stdio.h>
60 #include <strings.h>
61 #include <sys/param.h>
62 #include <sys/stat.h>
63 #include <unistd.h>
64 #include "ipmgmt_impl.h"
65 #include <zone.h>
66 #include <libipadm.h>
67 #include <libdladm.h>
68 #include <libdllink.h>
69 #include <net/route.h>
70 #include <ipadm_ipmgmt.h>
71 #include <sys/brand.h>
72 
73 const char		*progname;
74 
75 /* readers-writers lock for reading/writing daemon data store */
76 pthread_rwlock_t	ipmgmt_dbconf_lock = PTHREAD_RWLOCK_INITIALIZER;
77 
78 /* tracks address object to {ifname|logical number|interface id} mapping */
79 ipmgmt_aobjmap_list_t	aobjmap;
80 
81 /* used to communicate failure to parent process, which spawned the daemon */
82 static int		pfds[2];
83 
84 /* file descriptor to IPMGMT_DOOR */
85 static int		ipmgmt_door_fd = -1;
86 
87 static void		ipmgmt_exit(int);
88 static int		ipmgmt_init();
89 static int		ipmgmt_init_privileges();
90 static void		ipmgmt_ngz_persist_if();
91 
92 static ipadm_handle_t iph;
93 typedef struct ipmgmt_pif_s {
94 	struct ipmgmt_pif_s	*pif_next;
95 	char			pif_ifname[LIFNAMSIZ];
96 	boolean_t		pif_v4;
97 	boolean_t		pif_v6;
98 } ipmgmt_pif_t;
99 
100 static ipmgmt_pif_t *ngz_pifs;
101 
102 static int
103 ipmgmt_db_init()
104 {
105 	int		fd, err, scferr;
106 	scf_resources_t	res;
107 	boolean_t	upgrade = B_TRUE;
108 
109 	/*
110 	 * Check to see if we need to upgrade the data-store. We need to
111 	 * upgrade, if the version of the data-store does not match with
112 	 * IPADM_DB_VERSION. Further, if we cannot determine the current
113 	 * version of the data-store, we always err on the side of caution
114 	 * and upgrade the data-store to current version.
115 	 */
116 	if ((scferr = ipmgmt_create_scf_resources(IPMGMTD_FMRI, &res)) == 0)
117 		upgrade = ipmgmt_needs_upgrade(&res);
118 	if (upgrade) {
119 		err = ipmgmt_db_walk(ipmgmt_db_upgrade, NULL, IPADM_DB_WRITE);
120 		if (err != 0) {
121 			ipmgmt_log(LOG_ERR, "could not upgrade the "
122 			    "ipadm data-store: %s", strerror(err));
123 			err = 0;
124 		} else {
125 			/*
126 			 * upgrade was success, let's update SCF with the
127 			 * current data-store version number.
128 			 */
129 			if (scferr == 0)
130 				ipmgmt_update_dbver(&res);
131 		}
132 	}
133 	if (scferr == 0)
134 		ipmgmt_release_scf_resources(&res);
135 
136 	/* creates the address object data store, if it doesn't exist */
137 	if ((fd = open(ADDROBJ_MAPPING_DB_FILE, O_CREAT|O_RDONLY,
138 	    IPADM_FILE_MODE)) == -1) {
139 		err = errno;
140 		ipmgmt_log(LOG_ERR, "could not open %s: %s",
141 		    ADDROBJ_MAPPING_DB_FILE, strerror(err));
142 		return (err);
143 	}
144 	(void) close(fd);
145 
146 	aobjmap.aobjmap_head = NULL;
147 	(void) pthread_rwlock_init(&aobjmap.aobjmap_rwlock, NULL);
148 
149 	/*
150 	 * If the daemon is recovering from a crash or restart, read the
151 	 * address object to logical interface mapping and build an in-memory
152 	 * representation of the mapping. That is, build `aobjmap' structure
153 	 * from address object data store.
154 	 */
155 	if ((err = ipadm_rw_db(ipmgmt_aobjmap_init, NULL,
156 	    ADDROBJ_MAPPING_DB_FILE, 0, IPADM_DB_READ)) != 0) {
157 		/* if there was nothing to initialize, it's fine */
158 		if (err != ENOENT)
159 			return (err);
160 		err = 0;
161 	}
162 
163 	ipmgmt_ngz_persist_if(); /* create persistent interface info for NGZ */
164 
165 	return (err);
166 }
167 
168 static int
169 ipmgmt_door_init()
170 {
171 	int fd;
172 	int err;
173 
174 	/* create the door file for ipmgmtd */
175 	if ((fd = open(IPMGMT_DOOR, O_CREAT|O_RDONLY, IPADM_FILE_MODE)) == -1) {
176 		err = errno;
177 		ipmgmt_log(LOG_ERR, "could not open %s: %s",
178 		    IPMGMT_DOOR, strerror(err));
179 		return (err);
180 	}
181 	(void) close(fd);
182 
183 	if ((ipmgmt_door_fd = door_create(ipmgmt_handler, NULL,
184 	    DOOR_REFUSE_DESC | DOOR_NO_CANCEL)) == -1) {
185 		err = errno;
186 		ipmgmt_log(LOG_ERR, "failed to create door: %s", strerror(err));
187 		return (err);
188 	}
189 	/*
190 	 * fdetach first in case a previous daemon instance exited
191 	 * ungracefully.
192 	 */
193 	(void) fdetach(IPMGMT_DOOR);
194 	if (fattach(ipmgmt_door_fd, IPMGMT_DOOR) != 0) {
195 		err = errno;
196 		ipmgmt_log(LOG_ERR, "failed to attach door to %s: %s",
197 		    IPMGMT_DOOR, strerror(err));
198 		goto fail;
199 	}
200 	return (0);
201 fail:
202 	(void) door_revoke(ipmgmt_door_fd);
203 	ipmgmt_door_fd = -1;
204 	return (err);
205 }
206 
207 static void
208 ipmgmt_door_fini()
209 {
210 	if (ipmgmt_door_fd == -1)
211 		return;
212 
213 	(void) fdetach(IPMGMT_DOOR);
214 	if (door_revoke(ipmgmt_door_fd) == -1) {
215 		ipmgmt_log(LOG_ERR, "failed to revoke access to door %s: %s",
216 		    IPMGMT_DOOR, strerror(errno));
217 	}
218 }
219 
220 static int
221 ipmgmt_init()
222 {
223 	int err;
224 
225 	if (signal(SIGTERM, ipmgmt_exit) == SIG_ERR ||
226 	    signal(SIGINT, ipmgmt_exit) == SIG_ERR) {
227 		err = errno;
228 		ipmgmt_log(LOG_ERR, "signal() for SIGTERM/INT failed: %s",
229 		    strerror(err));
230 		return (err);
231 	}
232 	if ((err = ipmgmt_db_init()) != 0 || (err = ipmgmt_door_init()) != 0)
233 		return (err);
234 	return (0);
235 }
236 
237 /*
238  * This is called by the child process to inform the parent process to
239  * exit with the given return value.
240  */
241 static void
242 ipmgmt_inform_parent_exit(int rv)
243 {
244 	if (write(pfds[1], &rv, sizeof (int)) != sizeof (int)) {
245 		ipmgmt_log(LOG_WARNING,
246 		    "failed to inform parent process of status: %s",
247 		    strerror(errno));
248 		(void) close(pfds[1]);
249 		exit(EXIT_FAILURE);
250 	}
251 	(void) close(pfds[1]);
252 }
253 
254 /*ARGSUSED*/
255 static void
256 ipmgmt_exit(int signo)
257 {
258 	(void) close(pfds[1]);
259 	ipmgmt_door_fini();
260 	exit(EXIT_FAILURE);
261 }
262 
263 /*
264  * On the first reboot after installation of an ipkg zone,
265  * ipmgmt_persist_if_cb() is used in non-global zones to track the interfaces
266  * that have IP address configuration assignments from the global zone.
267  * Persistent configuration for the interfaces is created on the first boot
268  * by ipmgmtd, and the addresses assigned to the interfaces by the GZ
269  * will be subsequently configured when the interface is enabled.
270  * Note that ipmgmt_persist_if_cb() only sets up a list of interfaces
271  * that need to be persisted- the actual update of the ipadm data-store happens
272  * in ipmgmt_persist_if() after the appropriate privs/uid state has been set up.
273  */
274 static void
275 ipmgmt_persist_if_cb(char *ifname, boolean_t v4, boolean_t v6)
276 {
277 	ipmgmt_pif_t *pif;
278 
279 	pif = calloc(1, sizeof (*pif));
280 	if (pif == NULL) {
281 		ipmgmt_log(LOG_WARNING,
282 		    "Could not allocate memory to configure %s", ifname);
283 		return;
284 	}
285 	(void) strlcpy(pif->pif_ifname, ifname, sizeof (pif->pif_ifname));
286 	pif->pif_v4 = v4;
287 	pif->pif_v6 = v6;
288 	pif->pif_next = ngz_pifs;
289 	ngz_pifs = pif;
290 }
291 
292 /*
293  * ipmgmt_ngz_init() initializes exclusive-IP stack non-global zones by
294  * extracting configuration that has been saved in the kernel and applying
295  * it at zone boot.
296  */
297 static void
298 ipmgmt_ngz_init()
299 {
300 	zoneid_t zoneid;
301 	boolean_t firstboot = B_TRUE, s10c = B_FALSE;
302 	char brand[MAXNAMELEN];
303 	ipadm_status_t ipstatus;
304 
305 	zoneid = getzoneid();
306 	if (zoneid != GLOBAL_ZONEID) {
307 
308 		if (zone_getattr(zoneid, ZONE_ATTR_BRAND, brand,
309 		    sizeof (brand)) < 0) {
310 			ipmgmt_log(LOG_ERR, "Could not get brand name");
311 			return;
312 		}
313 		/*
314 		 * firstboot is always true for S10C zones, where ipadm is not
315 		 * available for restoring persistent configuration.
316 		 */
317 		if (strcmp(brand, NATIVE_BRAND_NAME) == 0)
318 			firstboot = ipmgmt_ngz_firstboot_postinstall();
319 		else
320 			s10c = B_TRUE;
321 
322 		if (!firstboot)
323 			return;
324 
325 		ipstatus = ipadm_open(&iph, IPH_IPMGMTD);
326 		if (ipstatus != IPADM_SUCCESS) {
327 			ipmgmt_log(LOG_ERR, "could not open ipadm handle",
328 			    ipadm_status2str(ipstatus));
329 			return;
330 		}
331 		/*
332 		 * Only pass down the callback to persist the interface
333 		 * for NATIVE (ipkg) zones.
334 		 */
335 		(void) ipadm_init_net_from_gz(iph, NULL,
336 		    (s10c ? NULL : ipmgmt_persist_if_cb));
337 		ipadm_close(iph);
338 	}
339 }
340 
341 /*
342  * Set the uid of this daemon to the "netadm" user. Finish the following
343  * operations before setuid() because they need root privileges:
344  *
345  *    - create the /etc/svc/volatile/ipadm directory;
346  *    - change its uid/gid to "netadm"/"netadm";
347  */
348 static int
349 ipmgmt_init_privileges()
350 {
351 	struct stat	statbuf;
352 	int		err;
353 
354 	/* create the IPADM_TMPFS_DIR directory */
355 	if (stat(IPADM_TMPFS_DIR, &statbuf) < 0) {
356 		if (mkdir(IPADM_TMPFS_DIR, (mode_t)0755) < 0) {
357 			err = errno;
358 			goto fail;
359 		}
360 	} else {
361 		if ((statbuf.st_mode & S_IFMT) != S_IFDIR) {
362 			err = ENOTDIR;
363 			goto fail;
364 		}
365 	}
366 
367 	if ((chmod(IPADM_TMPFS_DIR, 0755) < 0) ||
368 	    (chown(IPADM_TMPFS_DIR, UID_NETADM, GID_NETADM) < 0)) {
369 		err = errno;
370 		goto fail;
371 	}
372 
373 	/*
374 	 * initialize any NGZ specific network information before dropping
375 	 * privileges. We need these privileges to plumb IP interfaces handed
376 	 * down from the GZ (for dlpi_open() etc.) and also to configure the
377 	 * address itself (for any IPI_PRIV ioctls like SLIFADDR)
378 	 */
379 	ipmgmt_ngz_init();
380 
381 	/*
382 	 * Apply all protocol module properties. We need to apply all protocol
383 	 * properties before we drop root privileges.
384 	 */
385 	ipmgmt_init_prop();
386 
387 	/*
388 	 * limit the privileges of this daemon and set the uid of this
389 	 * daemon to UID_NETADM
390 	 */
391 	if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET, UID_NETADM,
392 	    GID_NETADM, NULL) == -1) {
393 		err = EPERM;
394 		goto fail;
395 	}
396 
397 	return (0);
398 fail:
399 	(void) ipmgmt_log(LOG_ERR, "failed to initialize the daemon: %s",
400 	    strerror(err));
401 	return (err);
402 }
403 
404 /*
405  * Keep the pfds fd open, close other fds.
406  */
407 /*ARGSUSED*/
408 static int
409 closefunc(void *arg, int fd)
410 {
411 	if (fd != pfds[1])
412 		(void) close(fd);
413 	return (0);
414 }
415 
416 /*
417  * We cannot use libc's daemon() because the door we create is associated with
418  * the process ID. If we create the door before the call to daemon(), it will
419  * be associated with the parent and it's incorrect. On the other hand if we
420  * create the door later, after the call to daemon(), parent process exits
421  * early and gives a false notion to SMF that 'ipmgmtd' is up and running,
422  * which is incorrect. So, we have our own daemon() equivalent.
423  */
424 static boolean_t
425 ipmgmt_daemonize(void)
426 {
427 	pid_t pid;
428 	int rv;
429 
430 	if (pipe(pfds) < 0) {
431 		(void) fprintf(stderr, "%s: pipe() failed: %s\n",
432 		    progname, strerror(errno));
433 		exit(EXIT_FAILURE);
434 	}
435 
436 	if ((pid = fork()) == -1) {
437 		(void) fprintf(stderr, "%s: fork() failed: %s\n",
438 		    progname, strerror(errno));
439 		exit(EXIT_FAILURE);
440 	} else if (pid > 0) { /* Parent */
441 		(void) close(pfds[1]);
442 
443 		/*
444 		 * Parent should not exit early, it should wait for the child
445 		 * to return Success/Failure. If the parent exits early, then
446 		 * SMF will think 'ipmgmtd' is up and would start all the
447 		 * depended services.
448 		 *
449 		 * If the child process exits unexpectedly, read() returns -1.
450 		 */
451 		if (read(pfds[0], &rv, sizeof (int)) != sizeof (int)) {
452 			(void) kill(pid, SIGKILL);
453 			rv = EXIT_FAILURE;
454 		}
455 
456 		(void) close(pfds[0]);
457 		exit(rv);
458 	}
459 
460 	/* Child */
461 	(void) close(pfds[0]);
462 	(void) setsid();
463 
464 	/* close all files except pfds[1] */
465 	(void) fdwalk(closefunc, NULL);
466 	(void) chdir("/");
467 	openlog(progname, LOG_PID, LOG_DAEMON);
468 	return (B_TRUE);
469 }
470 
471 int
472 main(int argc, char *argv[])
473 {
474 	int opt;
475 	boolean_t fg = B_FALSE;
476 
477 	progname = strrchr(argv[0], '/');
478 	if (progname != NULL)
479 		progname++;
480 	else
481 		progname = argv[0];
482 
483 	/* Process options */
484 	while ((opt = getopt(argc, argv, "f")) != EOF) {
485 		switch (opt) {
486 		case 'f':
487 			fg = B_TRUE;
488 			break;
489 		default:
490 			(void) fprintf(stderr, "Usage: %s [-f]\n", progname);
491 			return (EXIT_FAILURE);
492 		}
493 	}
494 
495 	if (!fg && getenv("SMF_FMRI") == NULL) {
496 		(void) fprintf(stderr,
497 		    "ipmgmtd is a smf(5) managed service and cannot be run "
498 		    "from the command line.\n");
499 		return (EINVAL);
500 	}
501 
502 	if (!fg && !ipmgmt_daemonize())
503 		return (EXIT_FAILURE);
504 
505 	if (ipmgmt_init_privileges() != 0)
506 		goto child_out;
507 
508 	if (ipmgmt_init() != 0)
509 		goto child_out;
510 
511 	/* Inform the parent process that it can successfully exit */
512 	ipmgmt_inform_parent_exit(EXIT_SUCCESS);
513 
514 	for (;;)
515 		(void) pause();
516 
517 child_out:
518 	/* return from main() forcibly exits an MT process */
519 	ipmgmt_inform_parent_exit(EXIT_FAILURE);
520 	return (EXIT_FAILURE);
521 }
522 
523 /*
524  * Return TRUE if `ifname' has persistent configuration for the `af' address
525  * family in the datastore
526  */
527 static boolean_t
528 ipmgmt_persist_if_exists(char *ifname, sa_family_t af)
529 {
530 	ipmgmt_getif_cbarg_t cbarg;
531 	boolean_t exists = B_FALSE;
532 	ipadm_if_info_t *ifp;
533 
534 	bzero(&cbarg, sizeof (cbarg));
535 	cbarg.cb_ifname = ifname;
536 	(void) ipmgmt_db_walk(ipmgmt_db_getif, &cbarg, IPADM_DB_READ);
537 	if ((ifp = cbarg.cb_ifinfo) != NULL) {
538 		if ((af == AF_INET && (ifp->ifi_pflags & IFIF_IPV4)) ||
539 		    (af == AF_INET6 && (ifp->ifi_pflags & IFIF_IPV6))) {
540 			exists = B_TRUE;
541 		}
542 	}
543 	free(ifp);
544 	return (exists);
545 }
546 
547 /*
548  * Persist any NGZ interfaces assigned to us from the global zone if they do
549  * not already exist in the persistent db. We need to
550  * do this before any calls to ipadm_enable_if() can succeed (i.e.,
551  * before opening up for door_calls), and after setuid to 'netadm' so that
552  * the persistent db is created with the right permissions.
553  */
554 static void
555 ipmgmt_ngz_persist_if()
556 {
557 	ipmgmt_pif_t *pif, *next;
558 	ipmgmt_if_arg_t ifarg;
559 
560 	for (pif = ngz_pifs; pif != NULL; pif = next) {
561 		next = pif->pif_next;
562 		bzero(&ifarg, sizeof (ifarg));
563 		(void) strlcpy(ifarg.ia_ifname, pif->pif_ifname,
564 		    sizeof (ifarg.ia_ifname));
565 		ifarg.ia_flags = IPMGMT_PERSIST;
566 		if (pif->pif_v4 &&
567 		    !ipmgmt_persist_if_exists(pif->pif_ifname, AF_INET)) {
568 			ifarg.ia_family = AF_INET;
569 			(void) ipmgmt_persist_if(&ifarg);
570 		}
571 		if (pif->pif_v6 &&
572 		    !ipmgmt_persist_if_exists(pif->pif_ifname, AF_INET6)) {
573 			ifarg.ia_family = AF_INET6;
574 			(void) ipmgmt_persist_if(&ifarg);
575 		}
576 		free(pif);
577 	}
578 	ngz_pifs = NULL; /* no red herrings */
579 }
580