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 (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2016-2017, Chris Fraire <cfraire@me.com>.
24 */
25
26 #include <sys/types.h>
27 #include <stdlib.h>
28 #include <assert.h>
29 #include <errno.h>
30 #include <locale.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include <signal.h>
34 #include <stdio.h>
35 #include <stdio_ext.h>
36 #include <dhcp_hostconf.h>
37 #include <dhcpagent_ipc.h>
38 #include <dhcpagent_util.h>
39 #include <dhcpmsg.h>
40 #include <dhcp_inittab.h>
41 #include <dhcp_symbol.h>
42 #include <netinet/dhcp.h>
43 #include <net/route.h>
44 #include <sys/sockio.h>
45 #include <sys/stat.h>
46 #include <stropts.h>
47 #include <fcntl.h>
48 #include <sys/scsi/adapters/iscsi_if.h>
49
50 #include "async.h"
51 #include "agent.h"
52 #include "script_handler.h"
53 #include "util.h"
54 #include "class_id.h"
55 #include "states.h"
56 #include "packet.h"
57 #include "interface.h"
58 #include "defaults.h"
59
60 #ifndef TEXT_DOMAIN
61 #define TEXT_DOMAIN "SYS_TEST"
62 #endif
63
64 iu_timer_id_t inactivity_id;
65 int class_id_len = 0;
66 char *class_id;
67 iu_eh_t *eh;
68 iu_tq_t *tq;
69 pid_t grandparent;
70 int rtsock_fd;
71
72 static boolean_t shutdown_started = B_FALSE;
73 static boolean_t do_adopt = B_FALSE;
74 static unsigned int debug_level = 0;
75 static iu_eh_callback_t accept_event, ipc_event, rtsock_event;
76 static void dhcp_smach_set_msg_reqhost(dhcp_smach_t *dsmp,
77 ipc_action_t *iap);
78 static DHCP_OPT * dhcp_get_ack_or_state(const dhcp_smach_t *dsmp,
79 const PKT_LIST *plp, uint_t codenum, boolean_t *did_alloc);
80
81 /*
82 * The ipc_cmd_allowed[] table indicates which IPC commands are allowed in
83 * which states; a non-zero value indicates the command is permitted.
84 *
85 * START is permitted if the state machine is fresh, or if we are in the
86 * process of trying to obtain a lease (as a convenience to save the
87 * administrator from having to do an explicit DROP). EXTEND, RELEASE, and
88 * GET_TAG require a lease to be obtained in order to make sense. INFORM is
89 * permitted if the interface is fresh or has an INFORM in progress or
90 * previously done on it -- otherwise a DROP or RELEASE is first required.
91 * PING and STATUS always make sense and thus are always permitted, as is DROP
92 * in order to permit the administrator to always bail out.
93 */
94 static int ipc_cmd_allowed[DHCP_NSTATES][DHCP_NIPC] = {
95 /* D E P R S S I G */
96 /* R X I E T T N E */
97 /* O T N L A A F T */
98 /* P E G E R T O _ */
99 /* . N . A T U R T */
100 /* . D . S . S M A */
101 /* . . . E . . . G */
102 /* INIT */ { 1, 0, 1, 0, 1, 1, 1, 0 },
103 /* SELECTING */ { 1, 0, 1, 0, 1, 1, 0, 0 },
104 /* REQUESTING */ { 1, 0, 1, 0, 1, 1, 0, 0 },
105 /* PRE_BOUND */ { 1, 1, 1, 1, 0, 1, 0, 1 },
106 /* BOUND */ { 1, 1, 1, 1, 0, 1, 0, 1 },
107 /* RENEWING */ { 1, 1, 1, 1, 0, 1, 0, 1 },
108 /* REBINDING */ { 1, 1, 1, 1, 0, 1, 0, 1 },
109 /* INFORMATION */ { 1, 0, 1, 0, 1, 1, 1, 1 },
110 /* INIT_REBOOT */ { 1, 0, 1, 1, 1, 1, 0, 0 },
111 /* ADOPTING */ { 1, 0, 1, 1, 0, 1, 0, 0 },
112 /* INFORM_SENT */ { 1, 0, 1, 0, 1, 1, 1, 0 },
113 /* DECLINING */ { 1, 1, 1, 1, 0, 1, 0, 1 },
114 /* RELEASING */ { 1, 0, 1, 0, 0, 1, 0, 1 },
115 };
116
117 #define CMD_ISPRIV 0x1 /* Command requires privileges */
118 #define CMD_CREATE 0x2 /* Command creates an interface */
119 #define CMD_BOOTP 0x4 /* Command is valid with BOOTP */
120 #define CMD_IMMED 0x8 /* Reply is immediate (no BUSY state) */
121
122 static uint_t ipc_cmd_flags[DHCP_NIPC] = {
123 /* DHCP_DROP */ CMD_ISPRIV|CMD_BOOTP,
124 /* DHCP_EXTEND */ CMD_ISPRIV,
125 /* DHCP_PING */ CMD_BOOTP|CMD_IMMED,
126 /* DHCP_RELEASE */ CMD_ISPRIV,
127 /* DHCP_START */ CMD_CREATE|CMD_ISPRIV|CMD_BOOTP,
128 /* DHCP_STATUS */ CMD_BOOTP|CMD_IMMED,
129 /* DHCP_INFORM */ CMD_CREATE|CMD_ISPRIV,
130 /* DHCP_GET_TAG */ CMD_BOOTP|CMD_IMMED
131 };
132
133 static boolean_t is_iscsi_active(void);
134
135 int
main(int argc,char ** argv)136 main(int argc, char **argv)
137 {
138 boolean_t is_daemon = B_TRUE;
139 boolean_t is_verbose;
140 int ipc_fd;
141 int c;
142 int aware = RTAW_UNDER_IPMP;
143 struct rlimit rl;
144
145 debug_level = df_get_int("", B_FALSE, DF_DEBUG_LEVEL);
146 is_verbose = df_get_bool("", B_FALSE, DF_VERBOSE);
147
148 /*
149 * -l is ignored for compatibility with old agent.
150 */
151
152 while ((c = getopt(argc, argv, "vd:l:fa")) != EOF) {
153
154 switch (c) {
155
156 case 'a':
157 do_adopt = B_TRUE;
158 grandparent = getpid();
159 break;
160
161 case 'd':
162 debug_level = strtoul(optarg, NULL, 0);
163 break;
164
165 case 'f':
166 is_daemon = B_FALSE;
167 break;
168
169 case 'v':
170 is_verbose = B_TRUE;
171 break;
172
173 case '?':
174 (void) fprintf(stderr, "usage: %s [-a] [-d n] [-f] [-v]"
175 "\n", argv[0]);
176 return (EXIT_FAILURE);
177
178 default:
179 break;
180 }
181 }
182
183 (void) setlocale(LC_ALL, "");
184 (void) textdomain(TEXT_DOMAIN);
185
186 if (geteuid() != 0) {
187 dhcpmsg_init(argv[0], B_FALSE, is_verbose, debug_level);
188 dhcpmsg(MSG_ERROR, "must be super-user");
189 dhcpmsg_fini();
190 return (EXIT_FAILURE);
191 }
192
193 if (is_daemon && daemonize() == 0) {
194 dhcpmsg_init(argv[0], B_FALSE, is_verbose, debug_level);
195 dhcpmsg(MSG_ERR, "cannot become daemon, exiting");
196 dhcpmsg_fini();
197 return (EXIT_FAILURE);
198 }
199
200 /*
201 * Seed the random number generator, since we're going to need it
202 * to set transaction id's and for exponential backoff.
203 */
204 srand48(gethrtime() ^ gethostid() ^ getpid());
205
206 dhcpmsg_init(argv[0], is_daemon, is_verbose, debug_level);
207 (void) atexit(dhcpmsg_fini);
208
209 tq = iu_tq_create();
210 eh = iu_eh_create();
211
212 if (eh == NULL || tq == NULL) {
213 errno = ENOMEM;
214 dhcpmsg(MSG_ERR, "cannot create timer queue or event handler");
215 return (EXIT_FAILURE);
216 }
217
218 /*
219 * ignore most signals that could be reasonably generated.
220 */
221
222 (void) signal(SIGTERM, graceful_shutdown);
223 (void) signal(SIGQUIT, graceful_shutdown);
224 (void) signal(SIGPIPE, SIG_IGN);
225 (void) signal(SIGUSR1, SIG_IGN);
226 (void) signal(SIGUSR2, SIG_IGN);
227 (void) signal(SIGINT, SIG_IGN);
228 (void) signal(SIGHUP, SIG_IGN);
229 (void) signal(SIGCHLD, SIG_IGN);
230
231 /*
232 * upon SIGTHAW we need to refresh any non-infinite leases.
233 */
234
235 (void) iu_eh_register_signal(eh, SIGTHAW, refresh_smachs, NULL);
236
237 class_id = get_class_id();
238 if (class_id != NULL)
239 class_id_len = strlen(class_id);
240 else
241 dhcpmsg(MSG_WARNING, "get_class_id failed, continuing "
242 "with no vendor class id");
243
244 /*
245 * the inactivity timer is enabled any time there are no
246 * interfaces under DHCP control. if DHCP_INACTIVITY_WAIT
247 * seconds transpire without an interface under DHCP control,
248 * the agent shuts down.
249 */
250
251 inactivity_id = iu_schedule_timer(tq, DHCP_INACTIVITY_WAIT,
252 inactivity_shutdown, NULL);
253
254 /*
255 * max out the number available descriptors, just in case..
256 */
257
258 rl.rlim_cur = RLIM_INFINITY;
259 rl.rlim_max = RLIM_INFINITY;
260 if (setrlimit(RLIMIT_NOFILE, &rl) == -1)
261 dhcpmsg(MSG_ERR, "setrlimit failed");
262
263 (void) enable_extended_FILE_stdio(-1, -1);
264
265 /*
266 * Create and bind default IP sockets used to control interfaces and to
267 * catch stray packets.
268 */
269
270 if (!dhcp_ip_default())
271 return (EXIT_FAILURE);
272
273 /*
274 * create the ipc channel that the agent will listen for
275 * requests on, and register it with the event handler so that
276 * `accept_event' will be called back.
277 */
278
279 switch (dhcp_ipc_init(&ipc_fd)) {
280
281 case 0:
282 break;
283
284 case DHCP_IPC_E_BIND:
285 dhcpmsg(MSG_ERROR, "dhcp_ipc_init: cannot bind to port "
286 "%i (agent already running?)", IPPORT_DHCPAGENT);
287 return (EXIT_FAILURE);
288
289 default:
290 dhcpmsg(MSG_ERROR, "dhcp_ipc_init failed");
291 return (EXIT_FAILURE);
292 }
293
294 if (iu_register_event(eh, ipc_fd, POLLIN, accept_event, 0) == -1) {
295 dhcpmsg(MSG_ERR, "cannot register ipc fd for messages");
296 return (EXIT_FAILURE);
297 }
298
299 /*
300 * Create the global routing socket. This is used for monitoring
301 * interface transitions, so that we learn about the kernel's Duplicate
302 * Address Detection status, and for inserting and removing default
303 * routes as learned from DHCP servers. Both v4 and v6 are handed
304 * with this one socket.
305 */
306 rtsock_fd = socket(PF_ROUTE, SOCK_RAW, 0);
307 if (rtsock_fd == -1) {
308 dhcpmsg(MSG_ERR, "cannot open routing socket");
309 return (EXIT_FAILURE);
310 }
311
312 /*
313 * We're IPMP-aware and can manage IPMP test addresses, so issue
314 * RT_AWARE to get routing socket messages for interfaces under IPMP.
315 */
316 if (setsockopt(rtsock_fd, SOL_ROUTE, RT_AWARE, &aware,
317 sizeof (aware)) == -1) {
318 dhcpmsg(MSG_ERR, "cannot set RT_AWARE on routing socket");
319 return (EXIT_FAILURE);
320 }
321
322 if (iu_register_event(eh, rtsock_fd, POLLIN, rtsock_event, 0) == -1) {
323 dhcpmsg(MSG_ERR, "cannot register routing socket for messages");
324 return (EXIT_FAILURE);
325 }
326
327 /*
328 * if the -a (adopt) option was specified, try to adopt the
329 * kernel-managed interface before we start.
330 */
331
332 if (do_adopt && !dhcp_adopt())
333 return (EXIT_FAILURE);
334
335 /*
336 * For DHCPv6, we own all of the interfaces marked DHCPRUNNING. As
337 * we're starting operation here, if there are any of those interfaces
338 * lingering around, they're strays, and need to be removed.
339 *
340 * It might be nice to save these addresses off somewhere -- for both
341 * v4 and v6 -- and use them as hints for later negotiation.
342 */
343 remove_v6_strays();
344
345 /*
346 * enter the main event loop; this is where all the real work
347 * takes place (through registering events and scheduling timers).
348 * this function only returns when the agent is shutting down.
349 */
350
351 switch (iu_handle_events(eh, tq)) {
352
353 case -1:
354 dhcpmsg(MSG_WARNING, "iu_handle_events exited abnormally");
355 break;
356
357 case DHCP_REASON_INACTIVITY:
358 dhcpmsg(MSG_INFO, "no interfaces to manage, shutting down...");
359 break;
360
361 case DHCP_REASON_TERMINATE:
362 dhcpmsg(MSG_INFO, "received SIGTERM, shutting down...");
363 break;
364
365 case DHCP_REASON_SIGNAL:
366 dhcpmsg(MSG_WARNING, "received unexpected signal, shutting "
367 "down...");
368 break;
369 }
370
371 (void) iu_eh_unregister_signal(eh, SIGTHAW, NULL);
372
373 iu_eh_destroy(eh);
374 iu_tq_destroy(tq);
375
376 return (EXIT_SUCCESS);
377 }
378
379 /*
380 * drain_script(): event loop callback during shutdown
381 *
382 * input: eh_t *: unused
383 * void *: unused
384 * output: boolean_t: B_TRUE if event loop should exit; B_FALSE otherwise
385 */
386
387 /* ARGSUSED */
388 boolean_t
drain_script(iu_eh_t * ehp,void * arg)389 drain_script(iu_eh_t *ehp, void *arg)
390 {
391 if (shutdown_started == B_FALSE) {
392 shutdown_started = B_TRUE;
393 /*
394 * Check if the system is diskless client and/or
395 * there are active iSCSI sessions
396 *
397 * Do not drop the lease, or the system will be
398 * unable to sync(dump) through nfs/iSCSI driver
399 */
400 if (!do_adopt && !is_iscsi_active()) {
401 nuke_smach_list();
402 }
403 }
404 return (script_count == 0);
405 }
406
407 /*
408 * accept_event(): accepts a new connection on the ipc socket and registers
409 * to receive its messages with the event handler
410 *
411 * input: iu_eh_t *: unused
412 * int: the file descriptor in the iu_eh_t * the connection came in on
413 * (other arguments unused)
414 * output: void
415 */
416
417 /* ARGSUSED */
418 static void
accept_event(iu_eh_t * ehp,int fd,short events,iu_event_id_t id,void * arg)419 accept_event(iu_eh_t *ehp, int fd, short events, iu_event_id_t id, void *arg)
420 {
421 int client_fd;
422 int is_priv;
423
424 if (dhcp_ipc_accept(fd, &client_fd, &is_priv) != 0) {
425 dhcpmsg(MSG_ERR, "accept_event: accept on ipc socket");
426 return;
427 }
428
429 if (iu_register_event(eh, client_fd, POLLIN, ipc_event,
430 (void *)is_priv) == -1) {
431 dhcpmsg(MSG_ERROR, "accept_event: cannot register ipc socket "
432 "for callback");
433 }
434 }
435
436 /*
437 * ipc_event(): processes incoming ipc requests
438 *
439 * input: iu_eh_t *: unused
440 * int: the file descriptor in the iu_eh_t * the request came in on
441 * short: unused
442 * iu_event_id_t: event ID
443 * void *: indicates whether the request is from a privileged client
444 * output: void
445 */
446
447 /* ARGSUSED */
448 static void
ipc_event(iu_eh_t * ehp,int fd,short events,iu_event_id_t id,void * arg)449 ipc_event(iu_eh_t *ehp, int fd, short events, iu_event_id_t id, void *arg)
450 {
451 ipc_action_t ia, *iap;
452 dhcp_smach_t *dsmp;
453 int error, is_priv = (int)arg;
454 const char *ifname;
455 boolean_t isv6;
456 boolean_t dsm_created = B_FALSE;
457
458 ipc_action_init(&ia);
459 error = dhcp_ipc_recv_request(fd, &ia.ia_request,
460 DHCP_IPC_REQUEST_WAIT);
461 if (error != DHCP_IPC_SUCCESS) {
462 if (error != DHCP_IPC_E_EOF) {
463 dhcpmsg(MSG_ERROR,
464 "ipc_event: dhcp_ipc_recv_request failed: %s",
465 dhcp_ipc_strerror(error));
466 } else {
467 dhcpmsg(MSG_DEBUG, "ipc_event: connection closed");
468 }
469 if ((dsmp = lookup_smach_by_event(id)) != NULL) {
470 ipc_action_finish(dsmp, error);
471 } else {
472 (void) iu_unregister_event(eh, id, NULL);
473 (void) dhcp_ipc_close(fd);
474 }
475 return;
476 }
477
478 /* Fill in temporary ipc_action structure for utility functions */
479 ia.ia_cmd = DHCP_IPC_CMD(ia.ia_request->message_type);
480 ia.ia_fd = fd;
481 ia.ia_eid = id;
482
483 if (ia.ia_cmd >= DHCP_NIPC) {
484 dhcpmsg(MSG_ERROR,
485 "ipc_event: invalid command (%s) attempted on %s",
486 dhcp_ipc_type_to_string(ia.ia_cmd), ia.ia_request->ifname);
487 send_error_reply(&ia, DHCP_IPC_E_CMD_UNKNOWN);
488 return;
489 }
490
491 /* return EPERM for any of the privileged actions */
492
493 if (!is_priv && (ipc_cmd_flags[ia.ia_cmd] & CMD_ISPRIV)) {
494 dhcpmsg(MSG_WARNING,
495 "ipc_event: privileged ipc command (%s) attempted on %s",
496 dhcp_ipc_type_to_string(ia.ia_cmd), ia.ia_request->ifname);
497 send_error_reply(&ia, DHCP_IPC_E_PERM);
498 return;
499 }
500
501 /*
502 * Try to locate the state machine associated with this command. If
503 * the command is DHCP_START or DHCP_INFORM and there isn't a state
504 * machine already, make one (there may already be one from a previous
505 * failed attempt to START or INFORM). Otherwise, verify the reference
506 * is still valid.
507 *
508 * The interface name may be blank. In that case, we look up the
509 * primary interface, and the requested type (v4 or v6) doesn't matter.
510 */
511
512 isv6 = (ia.ia_request->message_type & DHCP_V6) != 0;
513 ifname = ia.ia_request->ifname;
514 if (*ifname == '\0')
515 dsmp = primary_smach(isv6);
516 else
517 dsmp = lookup_smach(ifname, isv6);
518
519 if (dsmp != NULL) {
520 /* Note that verify_smach drops a reference */
521 hold_smach(dsmp);
522 if (!verify_smach(dsmp))
523 dsmp = NULL;
524 }
525
526 if (dsmp == NULL) {
527 /*
528 * If the user asked for the primary DHCP interface by giving
529 * an empty string and there is no primary, then check if we're
530 * handling dhcpinfo. If so, then simulate primary selection.
531 * Otherwise, report failure.
532 */
533 if (ifname[0] == '\0') {
534 if (ia.ia_cmd == DHCP_GET_TAG)
535 dsmp = info_primary_smach(isv6);
536 if (dsmp == NULL)
537 error = DHCP_IPC_E_NOPRIMARY;
538
539 /*
540 * If there's no interface, and we're starting up, then create
541 * it now, along with a state machine for it. Note that if
542 * insert_smach fails, it discards the LIF reference.
543 */
544 } else if (ipc_cmd_flags[ia.ia_cmd] & CMD_CREATE) {
545 dhcp_lif_t *lif;
546
547 lif = attach_lif(ifname, isv6, &error);
548 if (lif != NULL &&
549 (dsmp = insert_smach(lif, &error)) != NULL) {
550 /*
551 * Get client ID for logical interface. (V4
552 * only, because V6 plumbs its own interfaces.)
553 */
554 error = get_smach_cid(dsmp);
555 if (error != DHCP_IPC_SUCCESS) {
556 remove_smach(dsmp);
557 dsmp = NULL;
558 }
559 dsm_created = (dsmp != NULL);
560 }
561
562 /*
563 * Otherwise, this is an operation on an unknown interface.
564 */
565 } else {
566 error = DHCP_IPC_E_UNKIF;
567 }
568 if (dsmp == NULL) {
569 send_error_reply(&ia, error);
570 return;
571 }
572 }
573
574 /*
575 * If this is a request for DHCP to manage a lease on an address,
576 * ensure that IFF_DHCPRUNNING is set (we don't set this when the lif
577 * is created because the lif may have been created for INFORM).
578 */
579 if (ia.ia_cmd == DHCP_START &&
580 (error = set_lif_dhcp(dsmp->dsm_lif)) != DHCP_IPC_SUCCESS) {
581 if (dsm_created)
582 remove_smach(dsmp);
583 send_error_reply(&ia, error);
584 return;
585 }
586
587 if ((dsmp->dsm_dflags & DHCP_IF_BOOTP) &&
588 !(ipc_cmd_flags[ia.ia_cmd] & CMD_BOOTP)) {
589 dhcpmsg(MSG_ERROR, "command %s not valid for BOOTP on %s",
590 dhcp_ipc_type_to_string(ia.ia_cmd), dsmp->dsm_name);
591 send_error_reply(&ia, DHCP_IPC_E_BOOTP);
592 return;
593 }
594
595 /*
596 * verify that the state machine is in a state which will allow the
597 * command. we do this up front so that we can return an error
598 * *before* needlessly cancelling an in-progress transaction.
599 */
600
601 if (!check_cmd_allowed(dsmp->dsm_state, ia.ia_cmd)) {
602 dhcpmsg(MSG_DEBUG,
603 "in state %s; not allowing %s command on %s",
604 dhcp_state_to_string(dsmp->dsm_state),
605 dhcp_ipc_type_to_string(ia.ia_cmd), dsmp->dsm_name);
606 send_error_reply(&ia,
607 ia.ia_cmd == DHCP_START && dsmp->dsm_state != INIT ?
608 DHCP_IPC_E_RUNNING : DHCP_IPC_E_OUTSTATE);
609 return;
610 }
611
612 dhcpmsg(MSG_DEBUG, "in state %s; allowing %s command on %s",
613 dhcp_state_to_string(dsmp->dsm_state),
614 dhcp_ipc_type_to_string(ia.ia_cmd), dsmp->dsm_name);
615
616 if ((ia.ia_request->message_type & DHCP_PRIMARY) && is_priv)
617 make_primary(dsmp);
618
619 /*
620 * The current design dictates that there can be only one outstanding
621 * transaction per state machine -- this simplifies the code
622 * considerably and also fits well with RFCs 2131 and 3315. It is
623 * worth classifying the different DHCP commands into synchronous
624 * (those which we will handle now and reply to immediately) and
625 * asynchronous (those which require transactions and will be completed
626 * at an indeterminate time in the future):
627 *
628 * DROP: removes the agent's management of a state machine.
629 * asynchronous as the script program may be invoked.
630 *
631 * PING: checks to see if the agent has a named state machine.
632 * synchronous, since no packets need to be sent
633 * to the DHCP server.
634 *
635 * STATUS: returns information about a state machine.
636 * synchronous, since no packets need to be sent
637 * to the DHCP server.
638 *
639 * RELEASE: releases the agent's management of a state machine
640 * and brings the associated interfaces down. asynchronous
641 * as the script program may be invoked.
642 *
643 * EXTEND: renews a lease. asynchronous, since the agent
644 * needs to wait for an ACK, etc.
645 *
646 * START: starts DHCP on a named state machine. asynchronous since
647 * the agent needs to wait for OFFERs, ACKs, etc.
648 *
649 * INFORM: obtains configuration parameters for the system using
650 * externally configured interface. asynchronous, since the
651 * agent needs to wait for an ACK.
652 *
653 * Notice that EXTEND, INFORM, START, DROP and RELEASE are
654 * asynchronous. Notice also that asynchronous commands may occur from
655 * within the agent -- for instance, the agent will need to do implicit
656 * EXTENDs to extend the lease. In order to make the code simpler, the
657 * following rules apply for asynchronous commands:
658 *
659 * There can only be one asynchronous command at a time per state
660 * machine. The current asynchronous command is managed by the async_*
661 * api: async_start(), async_finish(), and async_cancel().
662 * async_start() starts management of a new asynchronous command on an
663 * state machine, which should only be done after async_cancel() to
664 * terminate a previous command. When the command is completed,
665 * async_finish() should be called.
666 *
667 * Asynchronous commands started by a user command have an associated
668 * ipc_action which provides the agent with information for how to get
669 * in touch with the user command when the action completes. These
670 * ipc_action records also have an associated timeout which may be
671 * infinite. ipc_action_start() should be called when starting an
672 * asynchronous command requested by a user, which sets up the timer
673 * and keeps track of the ipc information (file descriptor, request
674 * type). When the asynchronous command completes, ipc_action_finish()
675 * should be called to return a command status code to the user and
676 * close the ipc connection). If the command does not complete before
677 * the timer fires, ipc_action_timeout() is called which closes the ipc
678 * connection and returns DHCP_IPC_E_TIMEOUT to the user. Note that
679 * independent of ipc_action_timeout(), ipc_action_finish() should be
680 * called.
681 *
682 * on a case-by-case basis, here is what happens (per state machine):
683 *
684 * o When an asynchronous command is requested, then
685 * async_cancel() is called to terminate any non-user
686 * action in progress. If there's a user action running,
687 * the user command is sent DHCP_IPC_E_PEND.
688 *
689 * o otherwise, the transaction is started with
690 * async_start(). if the transaction is on behalf
691 * of a user, ipc_action_start() is called to keep
692 * track of the ipc information and set up the
693 * ipc_action timer.
694 *
695 * o if the command completes normally and before a
696 * timeout fires, then async_finish() is called.
697 * if there was an associated ipc_action,
698 * ipc_action_finish() is called to complete it.
699 *
700 * o if the command fails before a timeout fires, then
701 * async_finish() is called, and the state machine is
702 * is returned to a known state based on the command.
703 * if there was an associated ipc_action,
704 * ipc_action_finish() is called to complete it.
705 *
706 * o if the ipc_action timer fires before command
707 * completion, then DHCP_IPC_E_TIMEOUT is returned to
708 * the user. however, the transaction continues to
709 * be carried out asynchronously.
710 */
711
712 if (ipc_cmd_flags[ia.ia_cmd] & CMD_IMMED) {
713 /*
714 * Only immediate commands (ping, status, get_tag) need to
715 * worry about freeing ia through one of the reply functions
716 * before returning.
717 */
718 iap = &ia;
719 } else {
720 /*
721 * if shutdown request has been received, send back an error.
722 */
723 if (shutdown_started) {
724 send_error_reply(&ia, DHCP_IPC_E_OUTSTATE);
725 return;
726 }
727
728 if (dsmp->dsm_dflags & DHCP_IF_BUSY) {
729 send_error_reply(&ia, DHCP_IPC_E_PEND);
730 return;
731 }
732
733 if (!ipc_action_start(dsmp, &ia)) {
734 dhcpmsg(MSG_WARNING, "ipc_event: ipc_action_start "
735 "failed for %s", dsmp->dsm_name);
736 send_error_reply(&ia, DHCP_IPC_E_MEMORY);
737 return;
738 }
739
740 /* Action structure consumed by above function */
741 iap = &dsmp->dsm_ia;
742 }
743
744 switch (iap->ia_cmd) {
745
746 case DHCP_DROP:
747 if (dsmp->dsm_droprelease)
748 break;
749 dsmp->dsm_droprelease = B_TRUE;
750
751 /*
752 * Ensure that a timer associated with the existing state
753 * doesn't pop while we're waiting for the script to complete.
754 * (If so, chaos can result -- e.g., a timer causes us to end
755 * up in dhcp_selecting() would start acquiring a new lease on
756 * dsmp while our DHCP_DROP dismantling is ongoing.)
757 */
758 cancel_smach_timers(dsmp);
759 (void) script_start(dsmp, isv6 ? EVENT_DROP6 : EVENT_DROP,
760 dhcp_drop, NULL, NULL);
761 break; /* not an immediate function */
762
763 case DHCP_EXTEND:
764 dhcp_smach_set_msg_reqhost(dsmp, iap);
765 (void) dhcp_extending(dsmp);
766 break;
767
768 case DHCP_GET_TAG: {
769 dhcp_optnum_t optnum;
770 void *opt = NULL;
771 uint_t optlen;
772 boolean_t did_alloc = B_FALSE;
773 PKT_LIST *ack = dsmp->dsm_ack;
774 int i;
775
776 /*
777 * verify the request makes sense.
778 */
779
780 if (iap->ia_request->data_type != DHCP_TYPE_OPTNUM ||
781 iap->ia_request->data_length != sizeof (dhcp_optnum_t)) {
782 send_error_reply(iap, DHCP_IPC_E_PROTO);
783 break;
784 }
785
786 (void) memcpy(&optnum, iap->ia_request->buffer,
787 sizeof (dhcp_optnum_t));
788
789 load_option:
790 switch (optnum.category) {
791
792 case DSYM_SITE: /* FALLTHRU */
793 case DSYM_STANDARD:
794 for (i = 0; i < dsmp->dsm_pillen; i++) {
795 if (dsmp->dsm_pil[i] == optnum.code)
796 break;
797 }
798 if (i < dsmp->dsm_pillen)
799 break;
800 if (isv6) {
801 opt = dhcpv6_pkt_option(ack, NULL, optnum.code,
802 NULL);
803 } else {
804 opt = dhcp_get_ack_or_state(dsmp, ack,
805 optnum.code, &did_alloc);
806 }
807 break;
808
809 case DSYM_VENDOR:
810 if (isv6) {
811 dhcpv6_option_t *d6o;
812 uint32_t ent;
813
814 /*
815 * Look through vendor options to find our
816 * enterprise number.
817 */
818 d6o = NULL;
819 for (;;) {
820 d6o = dhcpv6_pkt_option(ack, d6o,
821 DHCPV6_OPT_VENDOR_OPT, &optlen);
822 if (d6o == NULL)
823 break;
824 optlen -= sizeof (*d6o);
825 if (optlen < sizeof (ent))
826 continue;
827 (void) memcpy(&ent, d6o + 1,
828 sizeof (ent));
829 if (ntohl(ent) != DHCPV6_SUN_ENT)
830 continue;
831 break;
832 }
833 if (d6o != NULL) {
834 /*
835 * Now find the requested vendor option
836 * within the vendor options block.
837 */
838 opt = dhcpv6_find_option(
839 (char *)(d6o + 1) + sizeof (ent),
840 optlen - sizeof (ent), NULL,
841 optnum.code, NULL);
842 }
843 } else {
844 /*
845 * the test against VS_OPTION_START is broken
846 * up into two tests to avoid compiler warnings
847 * under intel.
848 */
849 if ((optnum.code > VS_OPTION_START ||
850 optnum.code == VS_OPTION_START) &&
851 optnum.code <= VS_OPTION_END)
852 opt = ack->vs[optnum.code];
853 }
854 break;
855
856 case DSYM_FIELD:
857 if (isv6) {
858 dhcpv6_message_t *d6m =
859 (dhcpv6_message_t *)ack->pkt;
860 dhcpv6_option_t *d6o;
861
862 /* Validate the packet field the user wants */
863 optlen = optnum.code + optnum.size;
864 if (d6m->d6m_msg_type ==
865 DHCPV6_MSG_RELAY_FORW ||
866 d6m->d6m_msg_type ==
867 DHCPV6_MSG_RELAY_REPL) {
868 if (optlen > sizeof (dhcpv6_relay_t))
869 break;
870 } else {
871 if (optlen > sizeof (*d6m))
872 break;
873 }
874
875 opt = malloc(sizeof (*d6o) + optnum.size);
876 if (opt != NULL) {
877 d6o = opt;
878 d6o->d6o_code = htons(optnum.code);
879 d6o->d6o_len = htons(optnum.size);
880 (void) memcpy(d6o + 1, (caddr_t)d6m +
881 optnum.code, optnum.size);
882 }
883 } else {
884 if (optnum.code + optnum.size > sizeof (PKT))
885 break;
886
887 opt = malloc(optnum.size + DHCP_OPT_META_LEN);
888 if (opt != NULL) {
889 DHCP_OPT *v4opt = opt;
890
891 v4opt->len = optnum.size;
892 v4opt->code = optnum.code;
893 (void) memcpy(v4opt->value,
894 (caddr_t)ack->pkt + optnum.code,
895 optnum.size);
896 }
897 }
898
899 if (opt == NULL) {
900 send_error_reply(iap, DHCP_IPC_E_MEMORY);
901 return;
902 }
903 did_alloc = B_TRUE;
904 break;
905
906 default:
907 send_error_reply(iap, DHCP_IPC_E_PROTO);
908 return;
909 }
910
911 /*
912 * return the option payload, if there was one.
913 */
914
915 if (opt != NULL) {
916 if (isv6) {
917 dhcpv6_option_t d6ov;
918
919 (void) memcpy(&d6ov, opt, sizeof (d6ov));
920 optlen = ntohs(d6ov.d6o_len) + sizeof (d6ov);
921 } else {
922 optlen = ((DHCP_OPT *)opt)->len +
923 DHCP_OPT_META_LEN;
924 }
925 send_data_reply(iap, 0, DHCP_TYPE_OPTION, opt, optlen);
926
927 if (did_alloc)
928 free(opt);
929 break;
930 } else if (ack != dsmp->dsm_orig_ack) {
931 /*
932 * There wasn't any definition for the option in the
933 * current ack, so now retry with the original ack if
934 * the original ack is not the current ack.
935 */
936 ack = dsmp->dsm_orig_ack;
937 goto load_option;
938 }
939
940 /*
941 * note that an "okay" response is returned either in
942 * the case of an unknown option or a known option
943 * with no payload. this is okay (for now) since
944 * dhcpinfo checks whether an option is valid before
945 * ever performing ipc with the agent.
946 */
947
948 send_ok_reply(iap);
949 break;
950 }
951
952 case DHCP_INFORM:
953 dhcp_inform(dsmp);
954 /* next destination: dhcp_acknak() */
955 break; /* not an immediate function */
956
957 case DHCP_PING:
958 if (dsmp->dsm_dflags & DHCP_IF_FAILED)
959 send_error_reply(iap, DHCP_IPC_E_FAILEDIF);
960 else
961 send_ok_reply(iap);
962 break;
963
964 case DHCP_RELEASE:
965 if (dsmp->dsm_droprelease)
966 break;
967 dsmp->dsm_droprelease = B_TRUE;
968 cancel_smach_timers(dsmp); /* see comment in DHCP_DROP above */
969 (void) script_start(dsmp, isv6 ? EVENT_RELEASE6 :
970 EVENT_RELEASE, dhcp_release, "Finished with lease.", NULL);
971 break; /* not an immediate function */
972
973 case DHCP_START: {
974 PKT_LIST *ack, *oack;
975 PKT_LIST *plp[2];
976
977 deprecate_leases(dsmp);
978 dhcp_smach_set_msg_reqhost(dsmp, iap);
979
980 /*
981 * if we have a valid hostconf lying around, then jump
982 * into INIT_REBOOT. if it fails, we'll end up going
983 * through the whole selecting() procedure again.
984 */
985
986 error = read_hostconf(dsmp->dsm_name, plp, 2, dsmp->dsm_isv6);
987 ack = error > 0 ? plp[0] : NULL;
988 oack = error > 1 ? plp[1] : NULL;
989
990 /*
991 * If the allocation of the old ack fails, that's fine;
992 * continue without it.
993 */
994 if (oack == NULL)
995 oack = ack;
996
997 /*
998 * As long as we've allocated something, start using it.
999 */
1000 if (ack != NULL) {
1001 dsmp->dsm_orig_ack = oack;
1002 dsmp->dsm_ack = ack;
1003 dhcp_init_reboot(dsmp);
1004 /* next destination: dhcp_acknak() */
1005 break;
1006 }
1007
1008 /*
1009 * if not debugging, wait for a few seconds before
1010 * going into SELECTING.
1011 */
1012
1013 if (debug_level != 0 || !set_start_timer(dsmp)) {
1014 dhcp_selecting(dsmp);
1015 /* next destination: dhcp_requesting() */
1016 }
1017 /* else next destination: dhcp_start() */
1018 }
1019 break;
1020
1021 case DHCP_STATUS: {
1022 dhcp_status_t status;
1023 dhcp_lease_t *dlp;
1024
1025 status.if_began = monosec_to_time(dsmp->dsm_curstart_monosec);
1026
1027 /*
1028 * We return information on just the first lease as being
1029 * representative of the lot. A better status mechanism is
1030 * needed.
1031 */
1032 dlp = dsmp->dsm_leases;
1033
1034 if (dlp == NULL ||
1035 dlp->dl_lifs->lif_expire.dt_start == DHCP_PERM) {
1036 status.if_t1 = DHCP_PERM;
1037 status.if_t2 = DHCP_PERM;
1038 status.if_lease = DHCP_PERM;
1039 } else {
1040 status.if_t1 = status.if_began +
1041 dlp->dl_t1.dt_start;
1042 status.if_t2 = status.if_began +
1043 dlp->dl_t2.dt_start;
1044 status.if_lease = status.if_began +
1045 dlp->dl_lifs->lif_expire.dt_start;
1046 }
1047
1048 status.version = DHCP_STATUS_VER;
1049 status.if_state = dsmp->dsm_state;
1050 status.if_dflags = dsmp->dsm_dflags;
1051 status.if_sent = dsmp->dsm_sent;
1052 status.if_recv = dsmp->dsm_received;
1053 status.if_bad_offers = dsmp->dsm_bad_offers;
1054
1055 (void) strlcpy(status.if_name, dsmp->dsm_name, LIFNAMSIZ);
1056
1057 send_data_reply(iap, 0, DHCP_TYPE_STATUS, &status,
1058 sizeof (dhcp_status_t));
1059 break;
1060 }
1061 }
1062 }
1063
1064 /*
1065 * dhcp_smach_set_msg_reqhost(): set dsm_msg_reqhost based on the message
1066 * content of a DHCP IPC message
1067 *
1068 * input: dhcp_smach_t *: the state machine instance;
1069 * ipc_action_t *: the decoded DHCP IPC message;
1070 * output: void
1071 */
1072
1073 static void
dhcp_smach_set_msg_reqhost(dhcp_smach_t * dsmp,ipc_action_t * iap)1074 dhcp_smach_set_msg_reqhost(dhcp_smach_t *dsmp, ipc_action_t *iap)
1075 {
1076 DHCP_OPT *d4o;
1077 dhcp_symbol_t *entry;
1078 char *value;
1079
1080 if (dsmp->dsm_msg_reqhost != NULL) {
1081 dhcpmsg(MSG_DEBUG,
1082 "dhcp_smach_set_msg_reqhost: nullify former value, %s",
1083 dsmp->dsm_msg_reqhost);
1084 free(dsmp->dsm_msg_reqhost);
1085 dsmp->dsm_msg_reqhost = NULL;
1086 }
1087
1088 /*
1089 * if a STANDARD/HOSTNAME was sent in the IPC request, then copy that
1090 * value into the state machine data if decoding succeeds. Otherwise,
1091 * log to indicate at what step the decoding stopped.
1092 */
1093
1094 if (dsmp->dsm_isv6) {
1095 dhcpmsg(MSG_DEBUG, "dhcp_smach_set_msg_reqhost: ipv6 is not"
1096 " handled");
1097 return;
1098 } else if (iap->ia_request->data_type != DHCP_TYPE_OPTION) {
1099 dhcpmsg(MSG_DEBUG, "dhcp_smach_set_msg_reqhost: request type"
1100 " %d is not DHCP_TYPE_OPTION", iap->ia_request->data_type);
1101 return;
1102 }
1103
1104 if (iap->ia_request->data_length <= DHCP_OPT_META_LEN) {
1105 dhcpmsg(MSG_WARNING, "dhcp_smach_set_msg_reqhost:"
1106 " DHCP_TYPE_OPTION ia_request buffer is short");
1107 return;
1108 }
1109
1110 d4o = (DHCP_OPT *)iap->ia_request->buffer;
1111 if (d4o->code != CD_HOSTNAME) {
1112 dhcpmsg(MSG_DEBUG,
1113 "dhcp_smach_set_msg_reqhost: ignoring DHCPv4"
1114 " option %u", d4o->code);
1115 return;
1116 } else if (iap->ia_request->data_length - DHCP_OPT_META_LEN
1117 != d4o->len) {
1118 dhcpmsg(MSG_WARNING, "dhcp_smach_set_msg_reqhost:"
1119 " unexpected DHCP_OPT buffer length %u for CD_HOSTNAME"
1120 " option length %u", iap->ia_request->data_length,
1121 d4o->len);
1122 return;
1123 }
1124
1125 entry = inittab_getbycode(ITAB_CAT_STANDARD, ITAB_CONS_INFO,
1126 CD_HOSTNAME);
1127 if (entry == NULL) {
1128 dhcpmsg(MSG_WARNING,
1129 "dhcp_smach_set_msg_reqhost: error getting"
1130 " ITAB_CAT_STANDARD ITAB_CONS_INFO"
1131 " CD_HOSTNAME entry");
1132 return;
1133 }
1134
1135 value = inittab_decode(entry, d4o->value, d4o->len,
1136 /* just_payload */ B_TRUE);
1137 if (value == NULL) {
1138 dhcpmsg(MSG_WARNING,
1139 "dhcp_smach_set_msg_reqhost: error decoding"
1140 " CD_HOSTNAME value from DHCP_OPT");
1141 } else {
1142 dhcpmsg(MSG_DEBUG,
1143 "dhcp_smach_set_msg_reqhost: host %s", value);
1144 free(dsmp->dsm_msg_reqhost);
1145 dsmp->dsm_msg_reqhost = value;
1146 }
1147 free(entry);
1148 }
1149
1150 /*
1151 * dhcp_get_ack_or_state(): get a v4 option from the ACK or from the state
1152 * machine state for certain codes that are not ACKed (e.g., CD_CLIENT_ID)
1153 *
1154 * input: dhcp_smach_t *: the state machine instance;
1155 * PKT_LIST *: the decoded DHCP IPC message;
1156 * uint_t: the DHCP client option code;
1157 * boolean_t *: a pointer to a value that will be set to B_TRUE if
1158 * the return value must be freed (or else set to B_FALSE);
1159 * output: the option if found or else NULL.
1160 */
1161
1162 static DHCP_OPT *
dhcp_get_ack_or_state(const dhcp_smach_t * dsmp,const PKT_LIST * plp,uint_t codenum,boolean_t * did_alloc)1163 dhcp_get_ack_or_state(const dhcp_smach_t *dsmp, const PKT_LIST *plp,
1164 uint_t codenum, boolean_t *did_alloc)
1165 {
1166 DHCP_OPT *opt;
1167
1168 *did_alloc = B_FALSE;
1169
1170 if (codenum > DHCP_LAST_OPT)
1171 return (NULL);
1172
1173 /* check the ACK first for all codes */
1174 opt = plp->opts[codenum];
1175 if (opt != NULL)
1176 return (opt);
1177
1178 /* check the machine state also for certain codes */
1179 switch (codenum) {
1180 case CD_CLIENT_ID:
1181 /*
1182 * CD_CLIENT_ID is not sent in an ACK, but it's possibly
1183 * available from the state machine data
1184 */
1185
1186 if (dsmp->dsm_cidlen > 0) {
1187 if ((opt = malloc(dsmp->dsm_cidlen + DHCP_OPT_META_LEN))
1188 != NULL) {
1189 *did_alloc = B_TRUE;
1190 (void) encode_dhcp_opt(opt,
1191 B_FALSE /* is IPv6 */, CD_CLIENT_ID,
1192 dsmp->dsm_cid, dsmp->dsm_cidlen);
1193 }
1194 }
1195 break;
1196 default:
1197 break;
1198 }
1199 return (opt);
1200 }
1201
1202 /*
1203 * check_rtm_addr(): determine if routing socket message matches interface
1204 * address
1205 *
1206 * input: const struct if_msghdr *: pointer to routing socket message
1207 * int: routing socket message length
1208 * boolean_t: set to B_TRUE if IPv6
1209 * const in6_addr_t *: pointer to IP address
1210 * output: boolean_t: B_TRUE if address is a match
1211 */
1212
1213 static boolean_t
check_rtm_addr(const struct ifa_msghdr * ifam,int msglen,boolean_t isv6,const in6_addr_t * addr)1214 check_rtm_addr(const struct ifa_msghdr *ifam, int msglen, boolean_t isv6,
1215 const in6_addr_t *addr)
1216 {
1217 const char *cp, *lim;
1218 uint_t flag;
1219 const struct sockaddr *sa;
1220
1221 if (!(ifam->ifam_addrs & RTA_IFA))
1222 return (B_FALSE);
1223
1224 cp = (const char *)(ifam + 1);
1225 lim = (const char *)ifam + msglen;
1226 for (flag = 1; flag < RTA_IFA; flag <<= 1) {
1227 if (ifam->ifam_addrs & flag) {
1228 /* LINTED: alignment */
1229 sa = (const struct sockaddr *)cp;
1230 if ((const char *)(sa + 1) > lim)
1231 return (B_FALSE);
1232 switch (sa->sa_family) {
1233 case AF_INET:
1234 cp += sizeof (struct sockaddr_in);
1235 break;
1236 case AF_LINK:
1237 cp += sizeof (struct sockaddr_dl);
1238 break;
1239 case AF_INET6:
1240 cp += sizeof (struct sockaddr_in6);
1241 break;
1242 default:
1243 cp += sizeof (struct sockaddr);
1244 break;
1245 }
1246 }
1247 }
1248 if (isv6) {
1249 const struct sockaddr_in6 *sin6;
1250
1251 /* LINTED: alignment */
1252 sin6 = (const struct sockaddr_in6 *)cp;
1253 if ((const char *)(sin6 + 1) > lim)
1254 return (B_FALSE);
1255 if (sin6->sin6_family != AF_INET6)
1256 return (B_FALSE);
1257 return (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, addr));
1258 } else {
1259 const struct sockaddr_in *sinp;
1260 ipaddr_t v4addr;
1261
1262 /* LINTED: alignment */
1263 sinp = (const struct sockaddr_in *)cp;
1264 if ((const char *)(sinp + 1) > lim)
1265 return (B_FALSE);
1266 if (sinp->sin_family != AF_INET)
1267 return (B_FALSE);
1268 IN6_V4MAPPED_TO_IPADDR(addr, v4addr);
1269 return (sinp->sin_addr.s_addr == v4addr);
1270 }
1271 }
1272
1273 /*
1274 * is_rtm_v6(): determine if routing socket message is IPv6
1275 *
1276 * input: struct ifa_msghdr *: pointer to routing socket message
1277 * int: message length
1278 * output: boolean_t
1279 */
1280
1281 static boolean_t
is_rtm_v6(const struct ifa_msghdr * ifam,int msglen)1282 is_rtm_v6(const struct ifa_msghdr *ifam, int msglen)
1283 {
1284 const char *cp, *lim;
1285 uint_t flag;
1286 const struct sockaddr *sa;
1287
1288 cp = (const char *)(ifam + 1);
1289 lim = (const char *)ifam + msglen;
1290 for (flag = ifam->ifam_addrs; flag != 0; flag &= flag - 1) {
1291 /* LINTED: alignment */
1292 sa = (const struct sockaddr *)cp;
1293 if ((const char *)(sa + 1) > lim)
1294 return (B_FALSE);
1295 switch (sa->sa_family) {
1296 case AF_INET:
1297 return (B_FALSE);
1298 case AF_LINK:
1299 cp += sizeof (struct sockaddr_dl);
1300 break;
1301 case AF_INET6:
1302 return (B_TRUE);
1303 default:
1304 cp += sizeof (struct sockaddr);
1305 break;
1306 }
1307 }
1308 return (B_FALSE);
1309 }
1310
1311 /*
1312 * check_lif(): check the state of a given logical interface and its DHCP
1313 * lease. We've been told by the routing socket that the
1314 * corresponding ifIndex has changed. This may mean that DAD has
1315 * completed or failed.
1316 *
1317 * input: dhcp_lif_t *: pointer to the LIF
1318 * const struct ifa_msghdr *: routing socket message
1319 * int: size of routing socket message
1320 * output: boolean_t: B_TRUE if DAD has completed on this interface
1321 */
1322
1323 static boolean_t
check_lif(dhcp_lif_t * lif,const struct ifa_msghdr * ifam,int msglen)1324 check_lif(dhcp_lif_t *lif, const struct ifa_msghdr *ifam, int msglen)
1325 {
1326 boolean_t isv6, dad_wait, unplumb;
1327 int fd;
1328 struct lifreq lifr;
1329
1330 isv6 = lif->lif_pif->pif_isv6;
1331 fd = isv6 ? v6_sock_fd : v4_sock_fd;
1332
1333 /*
1334 * Get the real (64 bit) logical interface flags. Note that the
1335 * routing socket message has flags, but these are just the lower 32
1336 * bits.
1337 */
1338 unplumb = B_FALSE;
1339 (void) memset(&lifr, 0, sizeof (lifr));
1340 (void) strlcpy(lifr.lifr_name, lif->lif_name, sizeof (lifr.lifr_name));
1341 if (ioctl(fd, SIOCGLIFFLAGS, &lifr) == -1) {
1342 /*
1343 * Failing to retrieve flags means that the interface is gone.
1344 * It hasn't failed to verify with DAD, but we still have to
1345 * give up on it.
1346 */
1347 lifr.lifr_flags = 0;
1348 if (errno == ENXIO) {
1349 lif->lif_plumbed = B_FALSE;
1350 dhcpmsg(MSG_INFO, "%s has been removed; abandoning",
1351 lif->lif_name);
1352 if (!isv6)
1353 discard_default_routes(lif->lif_smachs);
1354 } else {
1355 dhcpmsg(MSG_ERR,
1356 "unable to retrieve interface flags on %s",
1357 lif->lif_name);
1358 }
1359 unplumb = B_TRUE;
1360 } else if (!check_rtm_addr(ifam, msglen, isv6, &lif->lif_v6addr)) {
1361 /*
1362 * If the message is not about this logical interface,
1363 * then just ignore it.
1364 */
1365 return (B_FALSE);
1366 } else if (lifr.lifr_flags & IFF_DUPLICATE) {
1367 dhcpmsg(MSG_ERROR, "interface %s has duplicate address",
1368 lif->lif_name);
1369 lif_mark_decline(lif, "duplicate address");
1370 close_ip_lif(lif);
1371 (void) open_ip_lif(lif, INADDR_ANY, B_TRUE);
1372 }
1373
1374 dad_wait = lif->lif_dad_wait;
1375 if (dad_wait) {
1376 dhcpmsg(MSG_VERBOSE, "check_lif: %s has finished DAD",
1377 lif->lif_name);
1378 lif->lif_dad_wait = B_FALSE;
1379 }
1380
1381 if (unplumb)
1382 unplumb_lif(lif);
1383
1384 return (dad_wait);
1385 }
1386
1387 /*
1388 * check_main_lif(): check the state of a main logical interface for a state
1389 * machine. This is used only for DHCPv6.
1390 *
1391 * input: dhcp_smach_t *: pointer to the state machine
1392 * const struct ifa_msghdr *: routing socket message
1393 * int: size of routing socket message
1394 * output: boolean_t: B_TRUE if LIF is ok.
1395 */
1396
1397 static boolean_t
check_main_lif(dhcp_smach_t * dsmp,const struct ifa_msghdr * ifam,int msglen)1398 check_main_lif(dhcp_smach_t *dsmp, const struct ifa_msghdr *ifam, int msglen)
1399 {
1400 dhcp_lif_t *lif = dsmp->dsm_lif;
1401 struct lifreq lifr;
1402
1403 /*
1404 * Get the real (64 bit) logical interface flags. Note that the
1405 * routing socket message has flags, but these are just the lower 32
1406 * bits.
1407 */
1408 (void) memset(&lifr, 0, sizeof (lifr));
1409 (void) strlcpy(lifr.lifr_name, lif->lif_name, sizeof (lifr.lifr_name));
1410 if (ioctl(v6_sock_fd, SIOCGLIFFLAGS, &lifr) == -1) {
1411 /*
1412 * Failing to retrieve flags means that the interface is gone.
1413 * Our state machine is now trash.
1414 */
1415 if (errno == ENXIO) {
1416 dhcpmsg(MSG_INFO, "%s has been removed; abandoning",
1417 lif->lif_name);
1418 } else {
1419 dhcpmsg(MSG_ERR,
1420 "unable to retrieve interface flags on %s",
1421 lif->lif_name);
1422 }
1423 return (B_FALSE);
1424 } else if (!check_rtm_addr(ifam, msglen, B_TRUE, &lif->lif_v6addr)) {
1425 /*
1426 * If the message is not about this logical interface,
1427 * then just ignore it.
1428 */
1429 return (B_TRUE);
1430 } else if (lifr.lifr_flags & IFF_DUPLICATE) {
1431 dhcpmsg(MSG_ERROR, "interface %s has duplicate address",
1432 lif->lif_name);
1433 return (B_FALSE);
1434 } else {
1435 return (B_TRUE);
1436 }
1437 }
1438
1439 /*
1440 * process_link_up_down(): check the state of a physical interface for up/down
1441 * transitions; must go through INIT_REBOOT state if
1442 * the link flaps.
1443 *
1444 * input: dhcp_pif_t *: pointer to the physical interface to check
1445 * const struct if_msghdr *: routing socket message
1446 * output: none
1447 */
1448
1449 static void
process_link_up_down(dhcp_pif_t * pif,const struct if_msghdr * ifm)1450 process_link_up_down(dhcp_pif_t *pif, const struct if_msghdr *ifm)
1451 {
1452 struct lifreq lifr;
1453 boolean_t isv6;
1454 int fd;
1455
1456 /*
1457 * If the message implies no change of flags, then we're done; no need
1458 * to check further. Note that if we have multiple state machines on a
1459 * single physical interface, this test keeps us from issuing an ioctl
1460 * for each one.
1461 */
1462 if ((ifm->ifm_flags & IFF_RUNNING) && pif->pif_running ||
1463 !(ifm->ifm_flags & IFF_RUNNING) && !pif->pif_running)
1464 return;
1465
1466 /*
1467 * We don't know what the real interface flags are, because the
1468 * if_index number is only 16 bits; we must go ask.
1469 */
1470 isv6 = pif->pif_isv6;
1471 fd = isv6 ? v6_sock_fd : v4_sock_fd;
1472 (void) memset(&lifr, 0, sizeof (lifr));
1473 (void) strlcpy(lifr.lifr_name, pif->pif_name, sizeof (lifr.lifr_name));
1474
1475 if (ioctl(fd, SIOCGLIFFLAGS, &lifr) == -1 ||
1476 !(lifr.lifr_flags & IFF_RUNNING)) {
1477 /*
1478 * If we've lost the interface or it has gone down, then
1479 * nothing special to do; just turn off the running flag.
1480 */
1481 pif_status(pif, B_FALSE);
1482 } else {
1483 /*
1484 * Interface has come back up: go through verification process.
1485 */
1486 pif_status(pif, B_TRUE);
1487 }
1488 }
1489
1490 /*
1491 * rtsock_event(): fetches routing socket messages and updates internal
1492 * interface state based on those messages.
1493 *
1494 * input: iu_eh_t *: unused
1495 * int: the routing socket file descriptor
1496 * (other arguments unused)
1497 * output: void
1498 */
1499
1500 /* ARGSUSED */
1501 static void
rtsock_event(iu_eh_t * ehp,int fd,short events,iu_event_id_t id,void * arg)1502 rtsock_event(iu_eh_t *ehp, int fd, short events, iu_event_id_t id, void *arg)
1503 {
1504 dhcp_smach_t *dsmp, *dsmnext;
1505 union {
1506 struct ifa_msghdr ifam;
1507 struct if_msghdr ifm;
1508 char buf[1024];
1509 } msg;
1510 uint16_t ifindex;
1511 int msglen;
1512 boolean_t isv6;
1513
1514 if ((msglen = read(fd, &msg, sizeof (msg))) <= 0)
1515 return;
1516
1517 /* Note that the routing socket interface index is just 16 bits */
1518 if (msg.ifm.ifm_type == RTM_IFINFO) {
1519 ifindex = msg.ifm.ifm_index;
1520 isv6 = (msg.ifm.ifm_flags & IFF_IPV6) ? B_TRUE : B_FALSE;
1521 } else if (msg.ifam.ifam_type == RTM_DELADDR ||
1522 msg.ifam.ifam_type == RTM_NEWADDR) {
1523 ifindex = msg.ifam.ifam_index;
1524 isv6 = is_rtm_v6(&msg.ifam, msglen);
1525 } else {
1526 return;
1527 }
1528
1529 for (dsmp = lookup_smach_by_uindex(ifindex, NULL, isv6);
1530 dsmp != NULL; dsmp = dsmnext) {
1531 DHCPSTATE oldstate;
1532 boolean_t lif_finished;
1533 boolean_t lease_removed;
1534 dhcp_lease_t *dlp, *dlnext;
1535
1536 /*
1537 * Note that script_start can call dhcp_drop directly, and
1538 * that will do release_smach.
1539 */
1540 dsmnext = lookup_smach_by_uindex(ifindex, dsmp, isv6);
1541 oldstate = dsmp->dsm_state;
1542
1543 /*
1544 * Ignore state machines that are currently processing drop or
1545 * release; there is nothing more we can do for them.
1546 */
1547 if (dsmp->dsm_droprelease)
1548 continue;
1549
1550 /*
1551 * Look for link up/down notifications. These occur on a
1552 * physical interface basis.
1553 */
1554 if (msg.ifm.ifm_type == RTM_IFINFO) {
1555 process_link_up_down(dsmp->dsm_lif->lif_pif, &msg.ifm);
1556 continue;
1557 }
1558
1559 /*
1560 * Since we cannot trust the flags reported by the routing
1561 * socket (they're just 32 bits -- and thus never include
1562 * IFF_DUPLICATE), and we can't trust the ifindex (it's only 16
1563 * bits and also doesn't reflect the alias in use), we get
1564 * flags on all matching interfaces, and go by that.
1565 */
1566 lif_finished = B_FALSE;
1567 lease_removed = B_FALSE;
1568 for (dlp = dsmp->dsm_leases; dlp != NULL; dlp = dlnext) {
1569 dhcp_lif_t *lif, *lifnext;
1570 uint_t nlifs = dlp->dl_nlifs;
1571
1572 dlnext = dlp->dl_next;
1573 for (lif = dlp->dl_lifs; lif != NULL && nlifs > 0;
1574 lif = lifnext, nlifs--) {
1575 lifnext = lif->lif_next;
1576 if (check_lif(lif, &msg.ifam, msglen)) {
1577 dsmp->dsm_lif_wait--;
1578 lif_finished = B_TRUE;
1579 }
1580 }
1581 if (dlp->dl_nlifs == 0) {
1582 remove_lease(dlp);
1583 lease_removed = B_TRUE;
1584 }
1585 }
1586
1587 if ((isv6 && !check_main_lif(dsmp, &msg.ifam, msglen)) ||
1588 (!isv6 && !verify_lif(dsmp->dsm_lif))) {
1589 finished_smach(dsmp, DHCP_IPC_E_INVIF);
1590 continue;
1591 }
1592
1593 /*
1594 * Ignore this state machine if nothing interesting has
1595 * happened.
1596 */
1597 if (!lif_finished && dsmp->dsm_lif_down == 0 &&
1598 (dsmp->dsm_leases != NULL || !lease_removed))
1599 continue;
1600
1601 /*
1602 * If we're still waiting for DAD to complete on some of the
1603 * configured LIFs, then don't send a response.
1604 */
1605 if (dsmp->dsm_lif_wait != 0) {
1606 dhcpmsg(MSG_VERBOSE, "rtsock_event: %s still has %d "
1607 "LIFs waiting on DAD", dsmp->dsm_name,
1608 dsmp->dsm_lif_wait);
1609 continue;
1610 }
1611
1612 /*
1613 * If we have some failed LIFs, then handle them now. We'll
1614 * remove them from the list. Any leases that become empty are
1615 * also removed as part of the decline-generation process.
1616 */
1617 if (dsmp->dsm_lif_down != 0)
1618 send_declines(dsmp);
1619
1620 if (dsmp->dsm_leases == NULL) {
1621 dsmp->dsm_bad_offers++;
1622 /*
1623 * For DHCPv6, we'll process the restart once we're
1624 * done sending Decline messages, because these are
1625 * supposed to be acknowledged. With DHCPv4, there's
1626 * no acknowledgment for a DECLINE, so after sending
1627 * it, we just restart right away.
1628 */
1629 if (!dsmp->dsm_isv6) {
1630 dhcpmsg(MSG_VERBOSE, "rtsock_event: %s has no "
1631 "LIFs left", dsmp->dsm_name);
1632 dhcp_restart(dsmp);
1633 }
1634 } else {
1635 /*
1636 * If we're now up on at least some of the leases and
1637 * we were waiting for that, then kick off the rest of
1638 * configuration. Lease validation and DAD are done.
1639 */
1640 dhcpmsg(MSG_VERBOSE, "rtsock_event: all LIFs verified "
1641 "on %s in %s state", dsmp->dsm_name,
1642 dhcp_state_to_string(oldstate));
1643 if (oldstate == PRE_BOUND ||
1644 oldstate == ADOPTING)
1645 dhcp_bound_complete(dsmp);
1646 if (oldstate == ADOPTING)
1647 dhcp_adopt_complete(dsmp);
1648 }
1649 }
1650 }
1651
1652 /*
1653 * check_cmd_allowed(): check whether the requested command is allowed in the
1654 * state specified.
1655 *
1656 * input: DHCPSTATE: current state
1657 * dhcp_ipc_type_t: requested command
1658 * output: boolean_t: B_TRUE if command is allowed in this state
1659 */
1660
1661 boolean_t
check_cmd_allowed(DHCPSTATE state,dhcp_ipc_type_t cmd)1662 check_cmd_allowed(DHCPSTATE state, dhcp_ipc_type_t cmd)
1663 {
1664 return (ipc_cmd_allowed[state][cmd] != 0);
1665 }
1666
1667 static boolean_t
is_iscsi_active(void)1668 is_iscsi_active(void)
1669 {
1670 int fd;
1671 int active = 0;
1672
1673 if ((fd = open(ISCSI_DRIVER_DEVCTL, O_RDONLY)) != -1) {
1674 if (ioctl(fd, ISCSI_IS_ACTIVE, &active) != 0)
1675 active = 0;
1676 (void) close(fd);
1677 }
1678
1679 return (active != 0);
1680 }
1681