1 /*-
2 * Copyright (C) 2000 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34
35 #include <sys/param.h>
36 #include <sys/malloc.h>
37 #include <sys/mbuf.h>
38 #include <sys/socket.h>
39 #include <sys/sockio.h>
40 #include <sys/systm.h>
41 #include <sys/queue.h>
42 #include <sys/sysctl.h>
43 #include <sys/syslog.h>
44
45 #include <net/if.h>
46 #include <net/vnet.h>
47
48 #include <netinet/in.h>
49
50 #include <netinet/ip6.h>
51 #include <netinet6/in6_var.h>
52 #include <netinet6/ip6_var.h>
53 #include <netinet6/scope6_var.h>
54
55 #ifdef ENABLE_DEFAULT_SCOPE
56 VNET_DEFINE(int, ip6_use_defzone) = 1;
57 #else
58 VNET_DEFINE(int, ip6_use_defzone) = 0;
59 #endif
60 VNET_DEFINE(int, deembed_scopeid) = 1;
61 SYSCTL_DECL(_net_inet6_ip6);
62 SYSCTL_VNET_INT(_net_inet6_ip6, OID_AUTO, deembed_scopeid, CTLFLAG_RW,
63 &VNET_NAME(deembed_scopeid), 0,
64 "Extract embedded zone ID and set it to sin6_scope_id in sockaddr_in6.");
65
66 /*
67 * The scope6_lock protects the global sid default stored in
68 * sid_default below.
69 */
70 static struct mtx scope6_lock;
71 #define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF)
72 #define SCOPE6_LOCK() mtx_lock(&scope6_lock)
73 #define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock)
74 #define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED)
75
76 static VNET_DEFINE(struct scope6_id, sid_default);
77 #define V_sid_default VNET(sid_default)
78
79 #define SID(ifp) \
80 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
81
82 static int scope6_get(struct ifnet *, struct scope6_id *);
83 static int scope6_set(struct ifnet *, struct scope6_id *);
84
85 void
scope6_init(void)86 scope6_init(void)
87 {
88
89 bzero(&V_sid_default, sizeof(V_sid_default));
90
91 if (!IS_DEFAULT_VNET(curvnet))
92 return;
93
94 SCOPE6_LOCK_INIT();
95 }
96
97 struct scope6_id *
scope6_ifattach(struct ifnet * ifp)98 scope6_ifattach(struct ifnet *ifp)
99 {
100 struct scope6_id *sid;
101
102 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK);
103 bzero(sid, sizeof(*sid));
104
105 /*
106 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
107 * Should we rather hardcode here?
108 */
109 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index;
110 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
111 #ifdef MULTI_SCOPE
112 /* by default, we don't care about scope boundary for these scopes. */
113 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1;
114 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1;
115 #endif
116
117 return sid;
118 }
119
120 void
scope6_ifdetach(struct scope6_id * sid)121 scope6_ifdetach(struct scope6_id *sid)
122 {
123
124 free(sid, M_IFADDR);
125 }
126
127 int
scope6_ioctl(u_long cmd,caddr_t data,struct ifnet * ifp)128 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
129 {
130 struct in6_ifreq *ifr;
131
132 if (ifp->if_afdata[AF_INET6] == NULL)
133 return (EPFNOSUPPORT);
134
135 ifr = (struct in6_ifreq *)data;
136 switch (cmd) {
137 case SIOCSSCOPE6:
138 return (scope6_set(ifp,
139 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
140 case SIOCGSCOPE6:
141 return (scope6_get(ifp,
142 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
143 case SIOCGSCOPE6DEF:
144 return (scope6_get_default(
145 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
146 default:
147 return (EOPNOTSUPP);
148 }
149 }
150
151 static int
scope6_set(struct ifnet * ifp,struct scope6_id * idlist)152 scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
153 {
154 int i;
155 int error = 0;
156 struct scope6_id *sid = NULL;
157
158 IF_AFDATA_WLOCK(ifp);
159 sid = SID(ifp);
160
161 if (!sid) { /* paranoid? */
162 IF_AFDATA_WUNLOCK(ifp);
163 return (EINVAL);
164 }
165
166 /*
167 * XXX: We need more consistency checks of the relationship among
168 * scopes (e.g. an organization should be larger than a site).
169 */
170
171 /*
172 * TODO(XXX): after setting, we should reflect the changes to
173 * interface addresses, routing table entries, PCB entries...
174 */
175
176 for (i = 0; i < 16; i++) {
177 if (idlist->s6id_list[i] &&
178 idlist->s6id_list[i] != sid->s6id_list[i]) {
179 /*
180 * An interface zone ID must be the corresponding
181 * interface index by definition.
182 */
183 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL &&
184 idlist->s6id_list[i] != ifp->if_index) {
185 IF_AFDATA_WUNLOCK(ifp);
186 return (EINVAL);
187 }
188
189 if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
190 idlist->s6id_list[i] > V_if_index) {
191 /*
192 * XXX: theoretically, there should be no
193 * relationship between link IDs and interface
194 * IDs, but we check the consistency for
195 * safety in later use.
196 */
197 IF_AFDATA_WUNLOCK(ifp);
198 return (EINVAL);
199 }
200
201 /*
202 * XXX: we must need lots of work in this case,
203 * but we simply set the new value in this initial
204 * implementation.
205 */
206 sid->s6id_list[i] = idlist->s6id_list[i];
207 }
208 }
209 IF_AFDATA_WUNLOCK(ifp);
210
211 return (error);
212 }
213
214 static int
scope6_get(struct ifnet * ifp,struct scope6_id * idlist)215 scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
216 {
217 struct scope6_id *sid;
218
219 /* We only need to lock the interface's afdata for SID() to work. */
220 IF_AFDATA_RLOCK(ifp);
221 sid = SID(ifp);
222 if (sid == NULL) { /* paranoid? */
223 IF_AFDATA_RUNLOCK(ifp);
224 return (EINVAL);
225 }
226
227 *idlist = *sid;
228
229 IF_AFDATA_RUNLOCK(ifp);
230 return (0);
231 }
232
233 /*
234 * Get a scope of the address. Node-local, link-local, site-local or global.
235 */
236 int
in6_addrscope(struct in6_addr * addr)237 in6_addrscope(struct in6_addr *addr)
238 {
239 int scope;
240
241 if (addr->s6_addr[0] == 0xfe) {
242 scope = addr->s6_addr[1] & 0xc0;
243
244 switch (scope) {
245 case 0x80:
246 return IPV6_ADDR_SCOPE_LINKLOCAL;
247 break;
248 case 0xc0:
249 return IPV6_ADDR_SCOPE_SITELOCAL;
250 break;
251 default:
252 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
253 break;
254 }
255 }
256
257
258 if (addr->s6_addr[0] == 0xff) {
259 scope = addr->s6_addr[1] & 0x0f;
260
261 /*
262 * due to other scope such as reserved,
263 * return scope doesn't work.
264 */
265 switch (scope) {
266 case IPV6_ADDR_SCOPE_INTFACELOCAL:
267 return IPV6_ADDR_SCOPE_INTFACELOCAL;
268 break;
269 case IPV6_ADDR_SCOPE_LINKLOCAL:
270 return IPV6_ADDR_SCOPE_LINKLOCAL;
271 break;
272 case IPV6_ADDR_SCOPE_SITELOCAL:
273 return IPV6_ADDR_SCOPE_SITELOCAL;
274 break;
275 default:
276 return IPV6_ADDR_SCOPE_GLOBAL;
277 break;
278 }
279 }
280
281 /*
282 * Regard loopback and unspecified addresses as global, since
283 * they have no ambiguity.
284 */
285 if (bcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) {
286 if (addr->s6_addr[15] == 1) /* loopback */
287 return IPV6_ADDR_SCOPE_LINKLOCAL;
288 if (addr->s6_addr[15] == 0) /* unspecified */
289 return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */
290 }
291
292 return IPV6_ADDR_SCOPE_GLOBAL;
293 }
294
295 /*
296 * ifp - note that this might be NULL
297 */
298
299 void
scope6_setdefault(struct ifnet * ifp)300 scope6_setdefault(struct ifnet *ifp)
301 {
302
303 /*
304 * Currently, this function just sets the default "interfaces"
305 * and "links" according to the given interface.
306 * We might eventually have to separate the notion of "link" from
307 * "interface" and provide a user interface to set the default.
308 */
309 SCOPE6_LOCK();
310 if (ifp) {
311 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
312 ifp->if_index;
313 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
314 ifp->if_index;
315 } else {
316 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
317 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
318 }
319 SCOPE6_UNLOCK();
320 }
321
322 int
scope6_get_default(struct scope6_id * idlist)323 scope6_get_default(struct scope6_id *idlist)
324 {
325
326 SCOPE6_LOCK();
327 *idlist = V_sid_default;
328 SCOPE6_UNLOCK();
329
330 return (0);
331 }
332
333 u_int32_t
scope6_addr2default(struct in6_addr * addr)334 scope6_addr2default(struct in6_addr *addr)
335 {
336 u_int32_t id;
337
338 /*
339 * special case: The loopback address should be considered as
340 * link-local, but there's no ambiguity in the syntax.
341 */
342 if (IN6_IS_ADDR_LOOPBACK(addr))
343 return (0);
344
345 /*
346 * XXX: 32-bit read is atomic on all our platforms, is it OK
347 * not to lock here?
348 */
349 SCOPE6_LOCK();
350 id = V_sid_default.s6id_list[in6_addrscope(addr)];
351 SCOPE6_UNLOCK();
352 return (id);
353 }
354
355 /*
356 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID
357 * is unspecified (=0), needs to be specified, and the default zone ID can be
358 * used, the default value will be used.
359 * This routine then generates the kernel-internal form: if the address scope
360 * of is interface-local or link-local, embed the interface index in the
361 * address.
362 */
363 int
sa6_embedscope(struct sockaddr_in6 * sin6,int defaultok)364 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok)
365 {
366 u_int32_t zoneid;
367
368 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok)
369 zoneid = scope6_addr2default(&sin6->sin6_addr);
370
371 if (zoneid != 0 &&
372 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
373 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) {
374 /*
375 * At this moment, we only check interface-local and
376 * link-local scope IDs, and use interface indices as the
377 * zone IDs assuming a one-to-one mapping between interfaces
378 * and links.
379 */
380 if (V_if_index < zoneid || ifnet_byindex(zoneid) == NULL)
381 return (ENXIO);
382
383 /* XXX assignment to 16bit from 32bit variable */
384 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff);
385 sin6->sin6_scope_id = 0;
386 }
387
388 return 0;
389 }
390
391 /*
392 * generate standard sockaddr_in6 from embedded form.
393 */
394 int
sa6_recoverscope(struct sockaddr_in6 * sin6)395 sa6_recoverscope(struct sockaddr_in6 *sin6)
396 {
397 char ip6buf[INET6_ADDRSTRLEN];
398 u_int32_t zoneid;
399
400 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
401 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) {
402 /*
403 * KAME assumption: link id == interface id
404 */
405 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]);
406 if (zoneid) {
407 /* sanity check */
408 if (V_if_index < zoneid)
409 return (ENXIO);
410 #if 0
411 /* XXX: Disabled due to possible deadlock. */
412 if (!ifnet_byindex(zoneid))
413 return (ENXIO);
414 #endif
415 if (sin6->sin6_scope_id != 0 &&
416 zoneid != sin6->sin6_scope_id) {
417 log(LOG_NOTICE,
418 "%s: embedded scope mismatch: %s%%%d. "
419 "sin6_scope_id was overridden.", __func__,
420 ip6_sprintf(ip6buf, &sin6->sin6_addr),
421 sin6->sin6_scope_id);
422 }
423 sin6->sin6_addr.s6_addr16[1] = 0;
424 sin6->sin6_scope_id = zoneid;
425 }
426 }
427
428 return 0;
429 }
430
431 /*
432 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is
433 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded
434 * in the in6_addr structure, in6 will be modified.
435 *
436 * ret_id - unnecessary?
437 */
438 int
in6_setscope(struct in6_addr * in6,struct ifnet * ifp,u_int32_t * ret_id)439 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
440 {
441 int scope;
442 u_int32_t zoneid = 0;
443 struct scope6_id *sid;
444
445 /*
446 * special case: the loopback address can only belong to a loopback
447 * interface.
448 */
449 if (IN6_IS_ADDR_LOOPBACK(in6)) {
450 if (!(ifp->if_flags & IFF_LOOPBACK))
451 return (EINVAL);
452 } else {
453 scope = in6_addrscope(in6);
454 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL ||
455 scope == IPV6_ADDR_SCOPE_LINKLOCAL) {
456 /*
457 * Currently we use interface indeces as the
458 * zone IDs for interface-local and link-local
459 * scopes.
460 */
461 zoneid = ifp->if_index;
462 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
463 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) {
464 IF_AFDATA_RLOCK(ifp);
465 sid = SID(ifp);
466 zoneid = sid->s6id_list[scope];
467 IF_AFDATA_RUNLOCK(ifp);
468 }
469 }
470
471 if (ret_id != NULL)
472 *ret_id = zoneid;
473
474 return (0);
475 }
476
477 /*
478 * Just clear the embedded scope identifier. Return 0 if the original address
479 * is intact; return non 0 if the address is modified.
480 */
481 int
in6_clearscope(struct in6_addr * in6)482 in6_clearscope(struct in6_addr *in6)
483 {
484 int modified = 0;
485
486 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
487 if (in6->s6_addr16[1] != 0)
488 modified = 1;
489 in6->s6_addr16[1] = 0;
490 }
491
492 return (modified);
493 }
494
495 /*
496 * Return the scope identifier or zero.
497 */
498 uint16_t
in6_getscope(struct in6_addr * in6)499 in6_getscope(struct in6_addr *in6)
500 {
501
502 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6))
503 return (in6->s6_addr16[1]);
504
505 return (0);
506 }
507