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) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 #include <sys/types.h>
27 #include <sys/systm.h>
28 #include <sys/stream.h>
29 #include <sys/cmn_err.h>
30 #include <sys/kmem.h>
31 #define _SUN_TPI_VERSION 2
32 #include <sys/tihdr.h>
33 #include <sys/stropts.h>
34 #include <sys/socket.h>
35 #include <sys/random.h>
36 #include <sys/policy.h>
37 #include <sys/tsol/tndb.h>
38 #include <sys/tsol/tnet.h>
39
40 #include <netinet/in.h>
41 #include <netinet/ip6.h>
42
43 #include <inet/common.h>
44 #include <inet/ip.h>
45 #include <inet/ip6.h>
46 #include <inet/ipclassifier.h>
47 #include "sctp_impl.h"
48 #include "sctp_asconf.h"
49 #include "sctp_addr.h"
50
51 /*
52 * Minimum number of associations which can be created per listener. Used
53 * when the listener association count is in effect.
54 */
55 static uint32_t sctp_min_assoc_listener = 2;
56
57 /*
58 * Returns 0 on success, EACCES on permission failure.
59 */
60 static int
61 sctp_select_port(sctp_t *sctp, in_port_t *requested_port, int *user_specified)
62 {
63 sctp_stack_t *sctps = sctp->sctp_sctps;
64 conn_t *connp = sctp->sctp_connp;
65
66 /*
67 * Get a valid port (within the anonymous range and should not
68 * be a privileged one) to use if the user has not given a port.
69 * If multiple threads are here, they may all start with
70 * with the same initial port. But, it should be fine as long as
71 * sctp_bindi will ensure that no two threads will be assigned
72 * the same port.
73 */
74 if (*requested_port == 0) {
75 *requested_port = sctp_update_next_port(
76 sctps->sctps_next_port_to_try,
77 crgetzone(connp->conn_cred), sctps);
78 if (*requested_port == 0)
79 return (EACCES);
80 *user_specified = 0;
81 } else {
82 int i;
83 boolean_t priv = B_FALSE;
84
85 /*
86 * If the requested_port is in the well-known privileged range,
87 * verify that the stream was opened by a privileged user.
88 * Note: No locks are held when inspecting sctp_g_*epriv_ports
89 * but instead the code relies on:
90 * - the fact that the address of the array and its size never
91 * changes
92 * - the atomic assignment of the elements of the array
93 */
94 if (*requested_port < sctps->sctps_smallest_nonpriv_port) {
95 priv = B_TRUE;
96 } else {
97 for (i = 0; i < sctps->sctps_g_num_epriv_ports; i++) {
98 if (*requested_port ==
99 sctps->sctps_g_epriv_ports[i]) {
100 priv = B_TRUE;
101 break;
102 }
103 }
104 }
105 if (priv) {
106 /*
107 * sctp_bind() should take a cred_t argument so that
108 * we can use it here.
109 */
110 if (secpolicy_net_privaddr(connp->conn_cred,
111 *requested_port, IPPROTO_SCTP) != 0) {
112 dprint(1,
113 ("sctp_bind(x): no prive for port %d",
114 *requested_port));
115 return (EACCES);
116 }
117 }
118 *user_specified = 1;
119 }
120
121 return (0);
122 }
123
124 int
125 sctp_listen(sctp_t *sctp)
126 {
127 sctp_tf_t *tf;
128 sctp_stack_t *sctps = sctp->sctp_sctps;
129 conn_t *connp = sctp->sctp_connp;
130
131 RUN_SCTP(sctp);
132 /*
133 * TCP handles listen() increasing the backlog, need to check
134 * if it should be handled here too
135 */
136 if (sctp->sctp_state > SCTPS_BOUND ||
137 (sctp->sctp_connp->conn_state_flags & CONN_CLOSING)) {
138 WAKE_SCTP(sctp);
139 return (EINVAL);
140 }
141
142 /* Do an anonymous bind for unbound socket doing listen(). */
143 if (sctp->sctp_nsaddrs == 0) {
144 struct sockaddr_storage ss;
145 int ret;
146
147 bzero(&ss, sizeof (ss));
148 ss.ss_family = connp->conn_family;
149
150 WAKE_SCTP(sctp);
151 if ((ret = sctp_bind(sctp, (struct sockaddr *)&ss,
152 sizeof (ss))) != 0)
153 return (ret);
154 RUN_SCTP(sctp)
155 }
156
157 /* Cache things in the ixa without any refhold */
158 ASSERT(!(connp->conn_ixa->ixa_free_flags & IXA_FREE_CRED));
159 connp->conn_ixa->ixa_cred = connp->conn_cred;
160 connp->conn_ixa->ixa_cpid = connp->conn_cpid;
161 if (is_system_labeled())
162 connp->conn_ixa->ixa_tsl = crgetlabel(connp->conn_cred);
163
164 sctp->sctp_state = SCTPS_LISTEN;
165 (void) random_get_pseudo_bytes(sctp->sctp_secret, SCTP_SECRET_LEN);
166 sctp->sctp_last_secret_update = ddi_get_lbolt64();
167 bzero(sctp->sctp_old_secret, SCTP_SECRET_LEN);
168
169 /*
170 * If there is an association limit, allocate and initialize
171 * the counter struct. Note that since listen can be called
172 * multiple times, the struct may have been allready allocated.
173 */
174 if (!list_is_empty(&sctps->sctps_listener_conf) &&
175 sctp->sctp_listen_cnt == NULL) {
176 sctp_listen_cnt_t *slc;
177 uint32_t ratio;
178
179 ratio = sctp_find_listener_conf(sctps,
180 ntohs(connp->conn_lport));
181 if (ratio != 0) {
182 uint32_t mem_ratio, tot_buf;
183
184 slc = kmem_alloc(sizeof (sctp_listen_cnt_t), KM_SLEEP);
185 /*
186 * Calculate the connection limit based on
187 * the configured ratio and maxusers. Maxusers
188 * are calculated based on memory size,
189 * ~ 1 user per MB. Note that the conn_rcvbuf
190 * and conn_sndbuf may change after a
191 * connection is accepted. So what we have
192 * is only an approximation.
193 */
194 if ((tot_buf = connp->conn_rcvbuf +
195 connp->conn_sndbuf) < MB) {
196 mem_ratio = MB / tot_buf;
197 slc->slc_max = maxusers / ratio * mem_ratio;
198 } else {
199 mem_ratio = tot_buf / MB;
200 slc->slc_max = maxusers / ratio / mem_ratio;
201 }
202 /* At least we should allow some associations! */
203 if (slc->slc_max < sctp_min_assoc_listener)
204 slc->slc_max = sctp_min_assoc_listener;
205 slc->slc_cnt = 1;
206 slc->slc_drop = 0;
207 sctp->sctp_listen_cnt = slc;
208 }
209 }
210
211
212 tf = &sctps->sctps_listen_fanout[SCTP_LISTEN_HASH(
213 ntohs(connp->conn_lport))];
214 sctp_listen_hash_insert(tf, sctp);
215
216 WAKE_SCTP(sctp);
217 return (0);
218 }
219
220 /*
221 * Bind the sctp_t to a sockaddr, which includes an address and other
222 * information, such as port or flowinfo.
223 */
224 int
225 sctp_bind(sctp_t *sctp, struct sockaddr *sa, socklen_t len)
226 {
227 int user_specified;
228 boolean_t bind_to_req_port_only;
229 in_port_t requested_port;
230 in_port_t allocated_port;
231 int err = 0;
232 conn_t *connp = sctp->sctp_connp;
233 uint_t scope_id;
234 sin_t *sin;
235 sin6_t *sin6;
236
237 ASSERT(sctp != NULL);
238
239 RUN_SCTP(sctp);
240
241 if ((sctp->sctp_state >= SCTPS_BOUND) ||
242 (sctp->sctp_connp->conn_state_flags & CONN_CLOSING) ||
243 (sa == NULL || len == 0)) {
244 /*
245 * Multiple binds not allowed for any SCTP socket
246 * Also binding with null address is not supported.
247 */
248 err = EINVAL;
249 goto done;
250 }
251
252 switch (sa->sa_family) {
253 case AF_INET:
254 sin = (sin_t *)sa;
255 if (len < sizeof (struct sockaddr_in) ||
256 connp->conn_family == AF_INET6) {
257 err = EINVAL;
258 goto done;
259 }
260 requested_port = ntohs(sin->sin_port);
261 break;
262 case AF_INET6:
263 sin6 = (sin6_t *)sa;
264 if (len < sizeof (struct sockaddr_in6) ||
265 connp->conn_family == AF_INET) {
266 err = EINVAL;
267 goto done;
268 }
269 requested_port = ntohs(sin6->sin6_port);
270 /* Set the flowinfo. */
271 connp->conn_flowinfo =
272 sin6->sin6_flowinfo & ~IPV6_VERS_AND_FLOW_MASK;
273
274 scope_id = sin6->sin6_scope_id;
275 if (scope_id != 0 && IN6_IS_ADDR_LINKSCOPE(&sin6->sin6_addr)) {
276 connp->conn_ixa->ixa_flags |= IXAF_SCOPEID_SET;
277 connp->conn_ixa->ixa_scopeid = scope_id;
278 connp->conn_incoming_ifindex = scope_id;
279 } else {
280 connp->conn_ixa->ixa_flags &= ~IXAF_SCOPEID_SET;
281 connp->conn_incoming_ifindex = connp->conn_bound_if;
282 }
283 break;
284 default:
285 err = EAFNOSUPPORT;
286 goto done;
287 }
288 bind_to_req_port_only = requested_port == 0 ? B_FALSE : B_TRUE;
289
290 err = sctp_select_port(sctp, &requested_port, &user_specified);
291 if (err != 0)
292 goto done;
293
294 if ((err = sctp_bind_add(sctp, sa, 1, B_TRUE,
295 user_specified == 1 ? htons(requested_port) : 0)) != 0) {
296 goto done;
297 }
298 err = sctp_bindi(sctp, requested_port, bind_to_req_port_only,
299 user_specified, &allocated_port);
300 if (err != 0) {
301 sctp_free_saddrs(sctp);
302 } else {
303 ASSERT(sctp->sctp_state == SCTPS_BOUND);
304 }
305 done:
306 WAKE_SCTP(sctp);
307 return (err);
308 }
309
310 /*
311 * Perform bind/unbind operation of a list of addresses on a sctp_t
312 */
313 int
314 sctp_bindx(sctp_t *sctp, const void *addrs, int addrcnt, int bindop)
315 {
316 ASSERT(sctp != NULL);
317 ASSERT(addrs != NULL);
318 ASSERT(addrcnt > 0);
319
320 switch (bindop) {
321 case SCTP_BINDX_ADD_ADDR:
322 return (sctp_bind_add(sctp, addrs, addrcnt, B_FALSE,
323 sctp->sctp_connp->conn_lport));
324 case SCTP_BINDX_REM_ADDR:
325 return (sctp_bind_del(sctp, addrs, addrcnt, B_FALSE));
326 default:
327 return (EINVAL);
328 }
329 }
330
331 /*
332 * Add a list of addresses to a sctp_t.
333 */
334 int
335 sctp_bind_add(sctp_t *sctp, const void *addrs, uint32_t addrcnt,
336 boolean_t caller_hold_lock, in_port_t port)
337 {
338 int err = 0;
339 boolean_t do_asconf = B_FALSE;
340 sctp_stack_t *sctps = sctp->sctp_sctps;
341 conn_t *connp = sctp->sctp_connp;
342
343 if (!caller_hold_lock)
344 RUN_SCTP(sctp);
345
346 if (sctp->sctp_state > SCTPS_ESTABLISHED ||
347 (sctp->sctp_connp->conn_state_flags & CONN_CLOSING)) {
348 if (!caller_hold_lock)
349 WAKE_SCTP(sctp);
350 return (EINVAL);
351 }
352
353 if (sctp->sctp_state > SCTPS_LISTEN) {
354 /*
355 * Let's do some checking here rather than undoing the
356 * add later (for these reasons).
357 */
358 if (!sctps->sctps_addip_enabled ||
359 !sctp->sctp_understands_asconf ||
360 !sctp->sctp_understands_addip) {
361 if (!caller_hold_lock)
362 WAKE_SCTP(sctp);
363 return (EINVAL);
364 }
365 do_asconf = B_TRUE;
366 }
367 /*
368 * On a clustered node, for an inaddr_any bind, we will pass the list
369 * of all the addresses in the global list, minus any address on the
370 * loopback interface, and expect the clustering susbsystem to give us
371 * the correct list for the 'port'. For explicit binds we give the
372 * list of addresses and the clustering module validates it for the
373 * 'port'.
374 *
375 * On a non-clustered node, cl_sctp_check_addrs will be NULL and
376 * we proceed as usual.
377 */
378 if (cl_sctp_check_addrs != NULL) {
379 uchar_t *addrlist = NULL;
380 size_t size = 0;
381 int unspec = 0;
382 boolean_t do_listen;
383 uchar_t *llist = NULL;
384 size_t lsize = 0;
385
386 /*
387 * If we are adding addresses after listening, but before
388 * an association is established, we need to update the
389 * clustering module with this info.
390 */
391 do_listen = !do_asconf && sctp->sctp_state > SCTPS_BOUND &&
392 cl_sctp_listen != NULL;
393
394 err = sctp_get_addrlist(sctp, addrs, &addrcnt, &addrlist,
395 &unspec, &size);
396 if (err != 0) {
397 ASSERT(addrlist == NULL);
398 ASSERT(addrcnt == 0);
399 ASSERT(size == 0);
400 if (!caller_hold_lock)
401 WAKE_SCTP(sctp);
402 SCTP_KSTAT(sctps, sctp_cl_check_addrs);
403 return (err);
404 }
405 ASSERT(addrlist != NULL);
406 (*cl_sctp_check_addrs)(connp->conn_family, port, &addrlist,
407 size, &addrcnt, unspec == 1);
408 if (addrcnt == 0) {
409 /* We free the list */
410 kmem_free(addrlist, size);
411 if (!caller_hold_lock)
412 WAKE_SCTP(sctp);
413 return (EINVAL);
414 }
415 if (do_listen) {
416 lsize = sizeof (in6_addr_t) * addrcnt;
417 llist = kmem_alloc(lsize, KM_SLEEP);
418 }
419 err = sctp_valid_addr_list(sctp, addrlist, addrcnt, llist,
420 lsize);
421 if (err == 0 && do_listen) {
422 (*cl_sctp_listen)(connp->conn_family, llist,
423 addrcnt, connp->conn_lport);
424 /* list will be freed by the clustering module */
425 } else if (err != 0 && llist != NULL) {
426 kmem_free(llist, lsize);
427 }
428 /* free the list we allocated */
429 kmem_free(addrlist, size);
430 } else {
431 err = sctp_valid_addr_list(sctp, addrs, addrcnt, NULL, 0);
432 }
433 if (err != 0) {
434 if (!caller_hold_lock)
435 WAKE_SCTP(sctp);
436 return (err);
437 }
438 /* Need to send ASCONF messages */
439 if (do_asconf) {
440 err = sctp_add_ip(sctp, addrs, addrcnt);
441 if (err != 0) {
442 sctp_del_saddr_list(sctp, addrs, addrcnt, B_FALSE);
443 if (!caller_hold_lock)
444 WAKE_SCTP(sctp);
445 return (err);
446 }
447 }
448 if (!caller_hold_lock)
449 WAKE_SCTP(sctp);
450 return (0);
451 }
452
453 /*
454 * Remove one or more addresses bound to the sctp_t.
455 */
456 int
457 sctp_bind_del(sctp_t *sctp, const void *addrs, uint32_t addrcnt,
458 boolean_t caller_hold_lock)
459 {
460 int error = 0;
461 boolean_t do_asconf = B_FALSE;
462 uchar_t *ulist = NULL;
463 size_t usize = 0;
464 sctp_stack_t *sctps = sctp->sctp_sctps;
465 conn_t *connp = sctp->sctp_connp;
466
467 if (!caller_hold_lock)
468 RUN_SCTP(sctp);
469
470 if (sctp->sctp_state > SCTPS_ESTABLISHED ||
471 (sctp->sctp_connp->conn_state_flags & CONN_CLOSING)) {
472 if (!caller_hold_lock)
473 WAKE_SCTP(sctp);
474 return (EINVAL);
475 }
476 /*
477 * Fail the remove if we are beyond listen, but can't send this
478 * to the peer.
479 */
480 if (sctp->sctp_state > SCTPS_LISTEN) {
481 if (!sctps->sctps_addip_enabled ||
482 !sctp->sctp_understands_asconf ||
483 !sctp->sctp_understands_addip) {
484 if (!caller_hold_lock)
485 WAKE_SCTP(sctp);
486 return (EINVAL);
487 }
488 do_asconf = B_TRUE;
489 }
490
491 /* Can't delete the last address nor all of the addresses */
492 if (sctp->sctp_nsaddrs == 1 || addrcnt >= sctp->sctp_nsaddrs) {
493 if (!caller_hold_lock)
494 WAKE_SCTP(sctp);
495 return (EINVAL);
496 }
497
498 if (cl_sctp_unlisten != NULL && !do_asconf &&
499 sctp->sctp_state > SCTPS_BOUND) {
500 usize = sizeof (in6_addr_t) * addrcnt;
501 ulist = kmem_alloc(usize, KM_SLEEP);
502 }
503
504 error = sctp_del_ip(sctp, addrs, addrcnt, ulist, usize);
505 if (error != 0) {
506 if (ulist != NULL)
507 kmem_free(ulist, usize);
508 if (!caller_hold_lock)
509 WAKE_SCTP(sctp);
510 return (error);
511 }
512 /* ulist will be non-NULL only if cl_sctp_unlisten is non-NULL */
513 if (ulist != NULL) {
514 ASSERT(cl_sctp_unlisten != NULL);
515 (*cl_sctp_unlisten)(connp->conn_family, ulist, addrcnt,
516 connp->conn_lport);
517 /* ulist will be freed by the clustering module */
518 }
519 if (!caller_hold_lock)
520 WAKE_SCTP(sctp);
521 return (error);
522 }
523
524 /*
525 * Returns 0 for success, errno value otherwise.
526 *
527 * If the "bind_to_req_port_only" parameter is set and the requested port
528 * number is available, then set allocated_port to it. If not available,
529 * return an error.
530 *
531 * If the "bind_to_req_port_only" parameter is not set and the requested port
532 * number is available, then set allocated_port to it. If not available,
533 * find the first anonymous port we can and set allocated_port to that. If no
534 * anonymous ports are available, return an error.
535 *
536 * In either case, when succeeding, update the sctp_t to record the port number
537 * and insert it in the bind hash table.
538 */
539 int
540 sctp_bindi(sctp_t *sctp, in_port_t port, boolean_t bind_to_req_port_only,
541 int user_specified, in_port_t *allocated_port)
542 {
543 /* number of times we have run around the loop */
544 int count = 0;
545 /* maximum number of times to run around the loop */
546 int loopmax;
547 sctp_stack_t *sctps = sctp->sctp_sctps;
548 conn_t *connp = sctp->sctp_connp;
549 zone_t *zone = crgetzone(connp->conn_cred);
550 zoneid_t zoneid = connp->conn_zoneid;
551
552 /*
553 * Lookup for free addresses is done in a loop and "loopmax"
554 * influences how long we spin in the loop
555 */
556 if (bind_to_req_port_only) {
557 /*
558 * If the requested port is busy, don't bother to look
559 * for a new one. Setting loop maximum count to 1 has
560 * that effect.
561 */
562 loopmax = 1;
563 } else {
564 /*
565 * If the requested port is busy, look for a free one
566 * in the anonymous port range.
567 * Set loopmax appropriately so that one does not look
568 * forever in the case all of the anonymous ports are in use.
569 */
570 loopmax = (sctps->sctps_largest_anon_port -
571 sctps->sctps_smallest_anon_port + 1);
572 }
573 do {
574 uint16_t lport;
575 sctp_tf_t *tbf;
576 sctp_t *lsctp;
577 int addrcmp;
578
579 lport = htons(port);
580
581 /*
582 * Ensure that the sctp_t is not currently in the bind hash.
583 * Hold the lock on the hash bucket to ensure that
584 * the duplicate check plus the insertion is an atomic
585 * operation.
586 *
587 * This function does an inline lookup on the bind hash list
588 * Make sure that we access only members of sctp_t
589 * and that we don't look at sctp_sctp, since we are not
590 * doing a SCTPB_REFHOLD. For more details please see the notes
591 * in sctp_compress()
592 */
593 sctp_bind_hash_remove(sctp);
594 tbf = &sctps->sctps_bind_fanout[SCTP_BIND_HASH(port)];
595 mutex_enter(&tbf->tf_lock);
596 for (lsctp = tbf->tf_sctp; lsctp != NULL;
597 lsctp = lsctp->sctp_bind_hash) {
598 conn_t *lconnp = lsctp->sctp_connp;
599
600 if (lport != lconnp->conn_lport ||
601 lsctp->sctp_state < SCTPS_BOUND)
602 continue;
603
604 /*
605 * On a labeled system, we must treat bindings to ports
606 * on shared IP addresses by sockets with MAC exemption
607 * privilege as being in all zones, as there's
608 * otherwise no way to identify the right receiver.
609 */
610 if (lconnp->conn_zoneid != zoneid &&
611 lconnp->conn_mac_mode == CONN_MAC_DEFAULT &&
612 connp->conn_mac_mode == CONN_MAC_DEFAULT)
613 continue;
614
615 addrcmp = sctp_compare_saddrs(sctp, lsctp);
616 if (addrcmp != SCTP_ADDR_DISJOINT) {
617 if (!connp->conn_reuseaddr) {
618 /* in use */
619 break;
620 } else if (lsctp->sctp_state == SCTPS_BOUND ||
621 lsctp->sctp_state == SCTPS_LISTEN) {
622 /*
623 * socket option SO_REUSEADDR is set
624 * on the binding sctp_t.
625 *
626 * We have found a match of IP source
627 * address and source port, which is
628 * refused regardless of the
629 * SO_REUSEADDR setting, so we break.
630 */
631 break;
632 }
633 }
634 }
635 if (lsctp != NULL) {
636 /* The port number is busy */
637 mutex_exit(&tbf->tf_lock);
638 } else {
639 if (is_system_labeled()) {
640 mlp_type_t addrtype, mlptype;
641 uint_t ipversion;
642
643 /*
644 * On a labeled system we must check the type
645 * of the binding requested by the user (either
646 * MLP or SLP on shared and private addresses),
647 * and that the user's requested binding
648 * is permitted.
649 */
650 if (connp->conn_family == AF_INET)
651 ipversion = IPV4_VERSION;
652 else
653 ipversion = IPV6_VERSION;
654
655 addrtype = tsol_mlp_addr_type(
656 connp->conn_allzones ? ALL_ZONES :
657 zone->zone_id,
658 ipversion,
659 connp->conn_family == AF_INET ?
660 (void *)&sctp->sctp_ipha->ipha_src :
661 (void *)&sctp->sctp_ip6h->ip6_src,
662 sctps->sctps_netstack->netstack_ip);
663
664 /*
665 * tsol_mlp_addr_type returns the possibilities
666 * for the selected address. Since all local
667 * addresses are either private or shared, the
668 * return value mlptSingle means "local address
669 * not valid (interface not present)."
670 */
671 if (addrtype == mlptSingle) {
672 mutex_exit(&tbf->tf_lock);
673 return (EADDRNOTAVAIL);
674 }
675 mlptype = tsol_mlp_port_type(zone, IPPROTO_SCTP,
676 port, addrtype);
677 if (mlptype != mlptSingle) {
678 if (secpolicy_net_bindmlp(connp->
679 conn_cred) != 0) {
680 mutex_exit(&tbf->tf_lock);
681 return (EACCES);
682 }
683 /*
684 * If we're binding a shared MLP, then
685 * make sure that this zone is the one
686 * that owns that MLP. Shared MLPs can
687 * be owned by at most one zone.
688 *
689 * No need to handle exclusive-stack
690 * zones since ALL_ZONES only applies
691 * to the shared stack.
692 */
693
694 if (mlptype == mlptShared &&
695 addrtype == mlptShared &&
696 connp->conn_zoneid !=
697 tsol_mlp_findzone(IPPROTO_SCTP,
698 lport)) {
699 mutex_exit(&tbf->tf_lock);
700 return (EACCES);
701 }
702 connp->conn_mlp_type = mlptype;
703 }
704 }
705 /*
706 * This port is ours. Insert in fanout and mark as
707 * bound to prevent others from getting the port
708 * number.
709 */
710 sctp->sctp_state = SCTPS_BOUND;
711 connp->conn_lport = lport;
712
713 ASSERT(&sctps->sctps_bind_fanout[
714 SCTP_BIND_HASH(port)] == tbf);
715 sctp_bind_hash_insert(tbf, sctp, 1);
716
717 mutex_exit(&tbf->tf_lock);
718
719 /*
720 * We don't want sctp_next_port_to_try to "inherit"
721 * a port number supplied by the user in a bind.
722 *
723 * This is the only place where sctp_next_port_to_try
724 * is updated. After the update, it may or may not
725 * be in the valid range.
726 */
727 if (user_specified == 0)
728 sctps->sctps_next_port_to_try = port + 1;
729
730 *allocated_port = port;
731
732 return (0);
733 }
734
735 if ((count == 0) && (user_specified)) {
736 /*
737 * We may have to return an anonymous port. So
738 * get one to start with.
739 */
740 port = sctp_update_next_port(
741 sctps->sctps_next_port_to_try,
742 zone, sctps);
743 user_specified = 0;
744 } else {
745 port = sctp_update_next_port(port + 1, zone, sctps);
746 }
747 if (port == 0)
748 break;
749
750 /*
751 * Don't let this loop run forever in the case where
752 * all of the anonymous ports are in use.
753 */
754 } while (++count < loopmax);
755
756 return (bind_to_req_port_only ? EADDRINUSE : EADDRNOTAVAIL);
757 }
758
759 /*
760 * Don't let port fall into the privileged range.
761 * Since the extra privileged ports can be arbitrary we also
762 * ensure that we exclude those from consideration.
763 * sctp_g_epriv_ports is not sorted thus we loop over it until
764 * there are no changes.
765 *
766 * Note: No locks are held when inspecting sctp_g_*epriv_ports
767 * but instead the code relies on:
768 * - the fact that the address of the array and its size never changes
769 * - the atomic assignment of the elements of the array
770 */
771 in_port_t
772 sctp_update_next_port(in_port_t port, zone_t *zone, sctp_stack_t *sctps)
773 {
774 int i;
775 boolean_t restart = B_FALSE;
776
777 retry:
778 if (port < sctps->sctps_smallest_anon_port)
779 port = sctps->sctps_smallest_anon_port;
780
781 if (port > sctps->sctps_largest_anon_port) {
782 if (restart)
783 return (0);
784 restart = B_TRUE;
785 port = sctps->sctps_smallest_anon_port;
786 }
787
788 if (port < sctps->sctps_smallest_nonpriv_port)
789 port = sctps->sctps_smallest_nonpriv_port;
790
791 for (i = 0; i < sctps->sctps_g_num_epriv_ports; i++) {
792 if (port == sctps->sctps_g_epriv_ports[i]) {
793 port++;
794 /*
795 * Make sure whether the port is in the
796 * valid range.
797 *
798 * XXX Note that if sctp_g_epriv_ports contains
799 * all the anonymous ports this will be an
800 * infinite loop.
801 */
802 goto retry;
803 }
804 }
805
806 if (is_system_labeled() &&
807 (i = tsol_next_port(zone, port, IPPROTO_SCTP, B_TRUE)) != 0) {
808 port = i;
809 goto retry;
810 }
811
812 return (port);
813 }