FreeBSD/Linux Kernel Cross Reference
sys/netinet6/scope6.c
1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (C) 2000 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $
32 */
33
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36
37 #include <sys/param.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/socket.h>
41 #include <sys/sockio.h>
42 #include <sys/systm.h>
43 #include <sys/queue.h>
44 #include <sys/sysctl.h>
45 #include <sys/syslog.h>
46
47 #include <net/if.h>
48 #include <net/if_var.h>
49 #include <net/vnet.h>
50
51 #include <netinet/in.h>
52
53 #include <netinet/ip6.h>
54 #include <netinet6/in6_var.h>
55 #include <netinet6/ip6_var.h>
56 #include <netinet6/scope6_var.h>
57
58 #ifdef ENABLE_DEFAULT_SCOPE
59 VNET_DEFINE(int, ip6_use_defzone) = 1;
60 #else
61 VNET_DEFINE(int, ip6_use_defzone) = 0;
62 #endif
63 VNET_DEFINE(int, deembed_scopeid) = 1;
64 SYSCTL_DECL(_net_inet6_ip6);
65 SYSCTL_INT(_net_inet6_ip6, OID_AUTO, deembed_scopeid, CTLFLAG_VNET | CTLFLAG_RW,
66 &VNET_NAME(deembed_scopeid), 0,
67 "Extract embedded zone ID and set it to sin6_scope_id in sockaddr_in6.");
68
69 /*
70 * The scope6_lock protects the global sid default stored in
71 * sid_default below.
72 */
73 static struct mtx scope6_lock;
74 #define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF)
75 #define SCOPE6_LOCK() mtx_lock(&scope6_lock)
76 #define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock)
77 #define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED)
78
79 VNET_DEFINE_STATIC(struct scope6_id, sid_default);
80 #define V_sid_default VNET(sid_default)
81
82 #define SID(ifp) \
83 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
84
85 static int scope6_get(struct ifnet *, struct scope6_id *);
86 static int scope6_set(struct ifnet *, struct scope6_id *);
87
88 void
89 scope6_init(void)
90 {
91
92 bzero(&V_sid_default, sizeof(V_sid_default));
93
94 if (!IS_DEFAULT_VNET(curvnet))
95 return;
96
97 SCOPE6_LOCK_INIT();
98 }
99
100 struct scope6_id *
101 scope6_ifattach(struct ifnet *ifp)
102 {
103 struct scope6_id *sid;
104
105 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO);
106 /*
107 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
108 * Should we rather hardcode here?
109 */
110 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index;
111 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
112 return (sid);
113 }
114
115 void
116 scope6_ifdetach(struct scope6_id *sid)
117 {
118
119 free(sid, M_IFADDR);
120 }
121
122 int
123 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
124 {
125 struct in6_ifreq *ifr;
126
127 if (ifp->if_afdata[AF_INET6] == NULL)
128 return (EPFNOSUPPORT);
129
130 ifr = (struct in6_ifreq *)data;
131 switch (cmd) {
132 case SIOCSSCOPE6:
133 return (scope6_set(ifp,
134 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
135 case SIOCGSCOPE6:
136 return (scope6_get(ifp,
137 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
138 case SIOCGSCOPE6DEF:
139 return (scope6_get_default(
140 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
141 default:
142 return (EOPNOTSUPP);
143 }
144 }
145
146 static int
147 scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
148 {
149 int i;
150 int error = 0;
151 struct scope6_id *sid = NULL;
152
153 IF_AFDATA_WLOCK(ifp);
154 sid = SID(ifp);
155
156 if (!sid) { /* paranoid? */
157 IF_AFDATA_WUNLOCK(ifp);
158 return (EINVAL);
159 }
160
161 /*
162 * XXX: We need more consistency checks of the relationship among
163 * scopes (e.g. an organization should be larger than a site).
164 */
165
166 /*
167 * TODO(XXX): after setting, we should reflect the changes to
168 * interface addresses, routing table entries, PCB entries...
169 */
170
171 for (i = 0; i < 16; i++) {
172 if (idlist->s6id_list[i] &&
173 idlist->s6id_list[i] != sid->s6id_list[i]) {
174 /*
175 * An interface zone ID must be the corresponding
176 * interface index by definition.
177 */
178 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL &&
179 idlist->s6id_list[i] != ifp->if_index) {
180 IF_AFDATA_WUNLOCK(ifp);
181 return (EINVAL);
182 }
183
184 if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
185 idlist->s6id_list[i] > V_if_index) {
186 /*
187 * XXX: theoretically, there should be no
188 * relationship between link IDs and interface
189 * IDs, but we check the consistency for
190 * safety in later use.
191 */
192 IF_AFDATA_WUNLOCK(ifp);
193 return (EINVAL);
194 }
195
196 /*
197 * XXX: we must need lots of work in this case,
198 * but we simply set the new value in this initial
199 * implementation.
200 */
201 sid->s6id_list[i] = idlist->s6id_list[i];
202 }
203 }
204 IF_AFDATA_WUNLOCK(ifp);
205
206 return (error);
207 }
208
209 static int
210 scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
211 {
212 struct scope6_id *sid;
213
214 /* We only need to lock the interface's afdata for SID() to work. */
215 IF_AFDATA_RLOCK(ifp);
216 sid = SID(ifp);
217 if (sid == NULL) { /* paranoid? */
218 IF_AFDATA_RUNLOCK(ifp);
219 return (EINVAL);
220 }
221
222 *idlist = *sid;
223
224 IF_AFDATA_RUNLOCK(ifp);
225 return (0);
226 }
227
228 /*
229 * Get a scope of the address. Node-local, link-local, site-local or global.
230 */
231 int
232 in6_addrscope(const struct in6_addr *addr)
233 {
234
235 if (IN6_IS_ADDR_MULTICAST(addr)) {
236 /*
237 * Addresses with reserved value F must be treated as
238 * global multicast addresses.
239 */
240 if (IPV6_ADDR_MC_SCOPE(addr) == 0x0f)
241 return (IPV6_ADDR_SCOPE_GLOBAL);
242 return (IPV6_ADDR_MC_SCOPE(addr));
243 }
244 if (IN6_IS_ADDR_LINKLOCAL(addr) ||
245 IN6_IS_ADDR_LOOPBACK(addr))
246 return (IPV6_ADDR_SCOPE_LINKLOCAL);
247 if (IN6_IS_ADDR_SITELOCAL(addr))
248 return (IPV6_ADDR_SCOPE_SITELOCAL);
249 return (IPV6_ADDR_SCOPE_GLOBAL);
250 }
251
252 /*
253 * ifp - note that this might be NULL
254 */
255
256 void
257 scope6_setdefault(struct ifnet *ifp)
258 {
259
260 /*
261 * Currently, this function just sets the default "interfaces"
262 * and "links" according to the given interface.
263 * We might eventually have to separate the notion of "link" from
264 * "interface" and provide a user interface to set the default.
265 */
266 SCOPE6_LOCK();
267 if (ifp) {
268 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
269 ifp->if_index;
270 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
271 ifp->if_index;
272 } else {
273 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
274 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
275 }
276 SCOPE6_UNLOCK();
277 }
278
279 int
280 scope6_get_default(struct scope6_id *idlist)
281 {
282
283 SCOPE6_LOCK();
284 *idlist = V_sid_default;
285 SCOPE6_UNLOCK();
286
287 return (0);
288 }
289
290 u_int32_t
291 scope6_addr2default(struct in6_addr *addr)
292 {
293 u_int32_t id;
294
295 /*
296 * special case: The loopback address should be considered as
297 * link-local, but there's no ambiguity in the syntax.
298 */
299 if (IN6_IS_ADDR_LOOPBACK(addr))
300 return (0);
301
302 /*
303 * XXX: 32-bit read is atomic on all our platforms, is it OK
304 * not to lock here?
305 */
306 SCOPE6_LOCK();
307 id = V_sid_default.s6id_list[in6_addrscope(addr)];
308 SCOPE6_UNLOCK();
309 return (id);
310 }
311
312 /*
313 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID
314 * is unspecified (=0), needs to be specified, and the default zone ID can be
315 * used, the default value will be used.
316 * This routine then generates the kernel-internal form: if the address scope
317 * of is interface-local or link-local, embed the interface index in the
318 * address.
319 */
320 int
321 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok)
322 {
323 u_int32_t zoneid;
324
325 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok)
326 zoneid = scope6_addr2default(&sin6->sin6_addr);
327
328 if (zoneid != 0 &&
329 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
330 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) {
331 /*
332 * At this moment, we only check interface-local and
333 * link-local scope IDs, and use interface indices as the
334 * zone IDs assuming a one-to-one mapping between interfaces
335 * and links.
336 */
337 if (V_if_index < zoneid || ifnet_byindex(zoneid) == NULL)
338 return (ENXIO);
339
340 /* XXX assignment to 16bit from 32bit variable */
341 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff);
342 sin6->sin6_scope_id = 0;
343 }
344
345 return 0;
346 }
347
348 /*
349 * generate standard sockaddr_in6 from embedded form.
350 */
351 int
352 sa6_recoverscope(struct sockaddr_in6 *sin6)
353 {
354 char ip6buf[INET6_ADDRSTRLEN];
355 u_int32_t zoneid;
356
357 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
358 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) {
359 /*
360 * KAME assumption: link id == interface id
361 */
362 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]);
363 if (zoneid) {
364 /* sanity check */
365 if (V_if_index < zoneid)
366 return (ENXIO);
367 #if 0
368 /* XXX: Disabled due to possible deadlock. */
369 if (!ifnet_byindex(zoneid))
370 return (ENXIO);
371 #endif
372 if (sin6->sin6_scope_id != 0 &&
373 zoneid != sin6->sin6_scope_id) {
374 log(LOG_NOTICE,
375 "%s: embedded scope mismatch: %s%%%d. "
376 "sin6_scope_id was overridden\n", __func__,
377 ip6_sprintf(ip6buf, &sin6->sin6_addr),
378 sin6->sin6_scope_id);
379 }
380 sin6->sin6_addr.s6_addr16[1] = 0;
381 sin6->sin6_scope_id = zoneid;
382 }
383 }
384
385 return 0;
386 }
387
388 /*
389 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is
390 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded
391 * in the in6_addr structure, in6 will be modified.
392 *
393 * ret_id - unnecessary?
394 */
395 int
396 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
397 {
398 int scope;
399 u_int32_t zoneid = 0;
400 struct scope6_id *sid;
401
402 /*
403 * special case: the loopback address can only belong to a loopback
404 * interface.
405 */
406 if (IN6_IS_ADDR_LOOPBACK(in6)) {
407 if (!(ifp->if_flags & IFF_LOOPBACK))
408 return (EINVAL);
409 } else {
410 scope = in6_addrscope(in6);
411 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL ||
412 scope == IPV6_ADDR_SCOPE_LINKLOCAL) {
413 /*
414 * Currently we use interface indices as the
415 * zone IDs for interface-local and link-local
416 * scopes.
417 */
418 zoneid = ifp->if_index;
419 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
420 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) {
421 IF_AFDATA_RLOCK(ifp);
422 if (ifp->if_afdata[AF_INET6] == NULL) {
423 IF_AFDATA_RUNLOCK(ifp);
424 return (ENETDOWN);
425 }
426 sid = SID(ifp);
427 zoneid = sid->s6id_list[scope];
428 IF_AFDATA_RUNLOCK(ifp);
429 }
430 }
431
432 if (ret_id != NULL)
433 *ret_id = zoneid;
434
435 return (0);
436 }
437
438 /*
439 * Just clear the embedded scope identifier. Return 0 if the original address
440 * is intact; return non 0 if the address is modified.
441 */
442 int
443 in6_clearscope(struct in6_addr *in6)
444 {
445 int modified = 0;
446
447 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
448 if (in6->s6_addr16[1] != 0)
449 modified = 1;
450 in6->s6_addr16[1] = 0;
451 }
452
453 return (modified);
454 }
455
456 /*
457 * Return the scope identifier or zero.
458 */
459 uint16_t
460 in6_getscope(const struct in6_addr *in6)
461 {
462
463 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6))
464 return (in6->s6_addr16[1]);
465
466 return (0);
467 }
468
469 /*
470 * Return pointer to ifnet structure, corresponding to the zone id of
471 * link-local scope.
472 */
473 struct ifnet*
474 in6_getlinkifnet(uint32_t zoneid)
475 {
476
477 return (ifnet_byindex((u_short)zoneid));
478 }
479
480 /*
481 * Return zone id for the specified scope.
482 */
483 uint32_t
484 in6_getscopezone(const struct ifnet *ifp, int scope)
485 {
486
487 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL ||
488 scope == IPV6_ADDR_SCOPE_LINKLOCAL)
489 return (ifp->if_index);
490 if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT)
491 return (SID(ifp)->s6id_list[scope]);
492 return (0);
493 }
494
495 /*
496 * Extracts scope from adddress @dst, stores cleared address
497 * inside @dst and zone inside @scopeid
498 */
499 void
500 in6_splitscope(const struct in6_addr *src, struct in6_addr *dst,
501 uint32_t *scopeid)
502 {
503 uint32_t zoneid;
504
505 *dst = *src;
506 zoneid = ntohs(in6_getscope(dst));
507 in6_clearscope(dst);
508 *scopeid = zoneid;
509 }
510
511 /*
512 * This function is for checking sockaddr_in6 structure passed
513 * from the application level (usually).
514 *
515 * sin6_scope_id should be set for link-local unicast, link-local and
516 * interface-local multicast addresses.
517 *
518 * If it is zero, then look into default zone ids. If default zone id is
519 * not set or disabled, then return error.
520 */
521 int
522 sa6_checkzone(struct sockaddr_in6 *sa6)
523 {
524 int scope;
525
526 scope = in6_addrscope(&sa6->sin6_addr);
527 if (scope == IPV6_ADDR_SCOPE_GLOBAL)
528 return (sa6->sin6_scope_id ? EINVAL: 0);
529 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) &&
530 scope != IPV6_ADDR_SCOPE_LINKLOCAL &&
531 scope != IPV6_ADDR_SCOPE_INTFACELOCAL) {
532 if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0)
533 sa6->sin6_scope_id = V_sid_default.s6id_list[scope];
534 return (0);
535 }
536 /*
537 * Since ::1 address always configured on the lo0, we can
538 * automatically set its zone id, when it is not specified.
539 * Return error, when specified zone id doesn't match with
540 * actual value.
541 */
542 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) {
543 if (sa6->sin6_scope_id == 0)
544 sa6->sin6_scope_id = in6_getscopezone(V_loif, scope);
545 else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope))
546 return (EADDRNOTAVAIL);
547 }
548 /* XXX: we can validate sin6_scope_id here */
549 if (sa6->sin6_scope_id != 0)
550 return (0);
551 if (V_ip6_use_defzone != 0)
552 sa6->sin6_scope_id = V_sid_default.s6id_list[scope];
553 /* Return error if we can't determine zone id */
554 return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL);
555 }
556
557 /*
558 * This function is similar to sa6_checkzone, but it uses given ifp
559 * to initialize sin6_scope_id.
560 */
561 int
562 sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6)
563 {
564 int scope;
565
566 scope = in6_addrscope(&sa6->sin6_addr);
567 if (scope == IPV6_ADDR_SCOPE_LINKLOCAL ||
568 scope == IPV6_ADDR_SCOPE_INTFACELOCAL) {
569 if (sa6->sin6_scope_id == 0) {
570 sa6->sin6_scope_id = in6_getscopezone(ifp, scope);
571 return (0);
572 } else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope))
573 return (EADDRNOTAVAIL);
574 }
575 return (sa6_checkzone(sa6));
576 }
577
578
Cache object: 0cfb617e967ac417f94aa6ab1f14f3fa
|