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: head/sys/netinet6/scope6.c 196019 2009-08-01 19:26:27Z rwatson $");
34
35#include <sys/param.h>
36#include <sys/malloc.h>
37#include <sys/mbuf.h>
38#include <sys/socket.h>
39#include <sys/systm.h>
40#include <sys/queue.h>
41#include <sys/syslog.h>
42
43#include <net/if.h>
44#include <net/vnet.h>
45
46#include <netinet/in.h>
47
48#include <netinet/ip6.h>
49#include <netinet6/in6_var.h>
50#include <netinet6/ip6_var.h>
51#include <netinet6/scope6_var.h>
52
53
54/*
55 * The scope6_lock protects the global sid default stored in
56 * sid_default below.
57 */
58static struct mtx scope6_lock;
59#define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF)
60#define SCOPE6_LOCK() mtx_lock(&scope6_lock)
61#define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock)
62#define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED)
63
64static VNET_DEFINE(struct scope6_id, sid_default);
65VNET_DEFINE(int, ip6_use_defzone);
66
67#define V_sid_default VNET(sid_default)
68
69#define SID(ifp) \
70 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
71
72void
73scope6_init(void)
74{
75
76#ifdef ENABLE_DEFAULT_SCOPE
77 V_ip6_use_defzone = 1;
78#else
79 V_ip6_use_defzone = 0;
80#endif
81 bzero(&V_sid_default, sizeof(V_sid_default));
82
83 if (!IS_DEFAULT_VNET(curvnet))
84 return;
85
86 SCOPE6_LOCK_INIT();
87}
88
89struct scope6_id *
90scope6_ifattach(struct ifnet *ifp)
91{
92 struct scope6_id *sid;
93
94 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK);
95 bzero(sid, sizeof(*sid));
96
97 /*
98 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
99 * Should we rather hardcode here?
100 */
101 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index;
102 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
103#ifdef MULTI_SCOPE
104 /* by default, we don't care about scope boundary for these scopes. */
105 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1;
106 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1;
107#endif
108
109 return sid;
110}
111
112void
113scope6_ifdetach(struct scope6_id *sid)
114{
115
116 free(sid, M_IFADDR);
117}
118
119int
120scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
121{
122 int i;
123 int error = 0;
124 struct scope6_id *sid = NULL;
125
126 IF_AFDATA_LOCK(ifp);
127 sid = SID(ifp);
128
129 if (!sid) { /* paranoid? */
130 IF_AFDATA_UNLOCK(ifp);
131 return (EINVAL);
132 }
133
134 /*
135 * XXX: We need more consistency checks of the relationship among
136 * scopes (e.g. an organization should be larger than a site).
137 */
138
139 /*
140 * TODO(XXX): after setting, we should reflect the changes to
141 * interface addresses, routing table entries, PCB entries...
142 */
143
144 SCOPE6_LOCK();
145 for (i = 0; i < 16; i++) {
146 if (idlist->s6id_list[i] &&
147 idlist->s6id_list[i] != sid->s6id_list[i]) {
148 /*
149 * An interface zone ID must be the corresponding
150 * interface index by definition.
151 */
152 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL &&
153 idlist->s6id_list[i] != ifp->if_index) {
154 IF_AFDATA_UNLOCK(ifp);
155 SCOPE6_UNLOCK();
156 return (EINVAL);
157 }
158
159 if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
160 idlist->s6id_list[i] > V_if_index) {
161 /*
162 * XXX: theoretically, there should be no
163 * relationship between link IDs and interface
164 * IDs, but we check the consistency for
165 * safety in later use.
166 */
167 IF_AFDATA_UNLOCK(ifp);
168 SCOPE6_UNLOCK();
169 return (EINVAL);
170 }
171
172 /*
173 * XXX: we must need lots of work in this case,
174 * but we simply set the new value in this initial
175 * implementation.
176 */
177 sid->s6id_list[i] = idlist->s6id_list[i];
178 }
179 }
180 SCOPE6_UNLOCK();
181 IF_AFDATA_UNLOCK(ifp);
182
183 return (error);
184}
185
186int
187scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
188{
189 /* We only need to lock the interface's afdata for SID() to work. */
190 IF_AFDATA_LOCK(ifp);
191 struct scope6_id *sid = SID(ifp);
192
193 if (sid == NULL) { /* paranoid? */
194 IF_AFDATA_UNLOCK(ifp);
195 return (EINVAL);
196 }
197
198 SCOPE6_LOCK();
199 *idlist = *sid;
200 SCOPE6_UNLOCK();
201
202 IF_AFDATA_UNLOCK(ifp);
203 return (0);
204}
205
206
207/*
208 * Get a scope of the address. Node-local, link-local, site-local or global.
209 */
210int
211in6_addrscope(struct in6_addr *addr)
212{
213 int scope;
214
215 if (addr->s6_addr[0] == 0xfe) {
216 scope = addr->s6_addr[1] & 0xc0;
217
218 switch (scope) {
219 case 0x80:
220 return IPV6_ADDR_SCOPE_LINKLOCAL;
221 break;
222 case 0xc0:
223 return IPV6_ADDR_SCOPE_SITELOCAL;
224 break;
225 default:
226 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
227 break;
228 }
229 }
230
231
232 if (addr->s6_addr[0] == 0xff) {
233 scope = addr->s6_addr[1] & 0x0f;
234
235 /*
236 * due to other scope such as reserved,
237 * return scope doesn't work.
238 */
239 switch (scope) {
240 case IPV6_ADDR_SCOPE_INTFACELOCAL:
241 return IPV6_ADDR_SCOPE_INTFACELOCAL;
242 break;
243 case IPV6_ADDR_SCOPE_LINKLOCAL:
244 return IPV6_ADDR_SCOPE_LINKLOCAL;
245 break;
246 case IPV6_ADDR_SCOPE_SITELOCAL:
247 return IPV6_ADDR_SCOPE_SITELOCAL;
248 break;
249 default:
250 return IPV6_ADDR_SCOPE_GLOBAL;
251 break;
252 }
253 }
254
255 /*
256 * Regard loopback and unspecified addresses as global, since
257 * they have no ambiguity.
258 */
259 if (bcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) {
260 if (addr->s6_addr[15] == 1) /* loopback */
261 return IPV6_ADDR_SCOPE_LINKLOCAL;
262 if (addr->s6_addr[15] == 0) /* unspecified */
263 return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */
264 }
265
266 return IPV6_ADDR_SCOPE_GLOBAL;
267}
268
269/*
270 * ifp - note that this might be NULL
271 */
272
273void
274scope6_setdefault(struct ifnet *ifp)
275{
276
277 /*
278 * Currently, this function just sets the default "interfaces"
279 * and "links" according to the given interface.
280 * We might eventually have to separate the notion of "link" from
281 * "interface" and provide a user interface to set the default.
282 */
283 SCOPE6_LOCK();
284 if (ifp) {
285 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
286 ifp->if_index;
287 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
288 ifp->if_index;
289 } else {
290 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
291 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
292 }
293 SCOPE6_UNLOCK();
294}
295
296int
297scope6_get_default(struct scope6_id *idlist)
298{
299
300 SCOPE6_LOCK();
301 *idlist = V_sid_default;
302 SCOPE6_UNLOCK();
303
304 return (0);
305}
306
307u_int32_t
308scope6_addr2default(struct in6_addr *addr)
309{
310 u_int32_t id;
311
312 /*
313 * special case: The loopback address should be considered as
314 * link-local, but there's no ambiguity in the syntax.
315 */
316 if (IN6_IS_ADDR_LOOPBACK(addr))
317 return (0);
318
319 /*
320 * XXX: 32-bit read is atomic on all our platforms, is it OK
321 * not to lock here?
322 */
323 SCOPE6_LOCK();
324 id = V_sid_default.s6id_list[in6_addrscope(addr)];
325 SCOPE6_UNLOCK();
326 return (id);
327}
328
329/*
330 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID
331 * is unspecified (=0), needs to be specified, and the default zone ID can be
332 * used, the default value will be used.
333 * This routine then generates the kernel-internal form: if the address scope
334 * of is interface-local or link-local, embed the interface index in the
335 * address.
336 */
337int
338sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok)
339{
340 struct ifnet *ifp;
341 u_int32_t zoneid;
342
343 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok)
344 zoneid = scope6_addr2default(&sin6->sin6_addr);
345
346 if (zoneid != 0 &&
347 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
348 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) {
349 /*
350 * At this moment, we only check interface-local and
351 * link-local scope IDs, and use interface indices as the
352 * zone IDs assuming a one-to-one mapping between interfaces
353 * and links.
354 */
355 if (V_if_index < zoneid)
356 return (ENXIO);
357 ifp = ifnet_byindex(zoneid);
358 if (ifp == NULL) /* XXX: this can happen for some OS */
359 return (ENXIO);
360
361 /* XXX assignment to 16bit from 32bit variable */
362 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff);
363
364 sin6->sin6_scope_id = 0;
365 }
366
367 return 0;
368}
369
370/*
371 * generate standard sockaddr_in6 from embedded form.
372 */
373int
374sa6_recoverscope(struct sockaddr_in6 *sin6)
375{
376 char ip6buf[INET6_ADDRSTRLEN];
377 u_int32_t zoneid;
378
379 if (sin6->sin6_scope_id != 0) {
380 log(LOG_NOTICE,
381 "sa6_recoverscope: assumption failure (non 0 ID): %s%%%d\n",
382 ip6_sprintf(ip6buf, &sin6->sin6_addr), sin6->sin6_scope_id);
383 /* XXX: proceed anyway... */
384 }
385 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
386 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) {
387 /*
388 * KAME assumption: link id == interface id
389 */
390 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]);
391 if (zoneid) {
392 /* sanity check */
393 if (zoneid < 0 || V_if_index < zoneid)
394 return (ENXIO);
395 if (!ifnet_byindex(zoneid))
396 return (ENXIO);
397 sin6->sin6_addr.s6_addr16[1] = 0;
398 sin6->sin6_scope_id = zoneid;
399 }
400 }
401
402 return 0;
403}
404
405/*
406 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is
407 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded
408 * in the in6_addr structure, in6 will be modified.
409 *
410 * ret_id - unnecessary?
411 */
412int
413in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
414{
415 int scope;
416 u_int32_t zoneid = 0;
417 struct scope6_id *sid;
418
419 IF_AFDATA_LOCK(ifp);
420
421 sid = SID(ifp);
422
423#ifdef DIAGNOSTIC
424 if (sid == NULL) { /* should not happen */
425 panic("in6_setscope: scope array is NULL");
426 /* NOTREACHED */
427 }
428#endif
429
430 /*
431 * special case: the loopback address can only belong to a loopback
432 * interface.
433 */
434 if (IN6_IS_ADDR_LOOPBACK(in6)) {
435 if (!(ifp->if_flags & IFF_LOOPBACK)) {
436 IF_AFDATA_UNLOCK(ifp);
437 return (EINVAL);
438 } else {
439 if (ret_id != NULL)
440 *ret_id = 0; /* there's no ambiguity */
441 IF_AFDATA_UNLOCK(ifp);
442 return (0);
443 }
444 }
445
446 scope = in6_addrscope(in6);
447
448 SCOPE6_LOCK();
449 switch (scope) {
450 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */
451 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL];
452 break;
453
454 case IPV6_ADDR_SCOPE_LINKLOCAL:
455 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL];
456 break;
457
458 case IPV6_ADDR_SCOPE_SITELOCAL:
459 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL];
460 break;
461
462 case IPV6_ADDR_SCOPE_ORGLOCAL:
463 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL];
464 break;
465
466 default:
467 zoneid = 0; /* XXX: treat as global. */
468 break;
469 }
470 SCOPE6_UNLOCK();
471 IF_AFDATA_UNLOCK(ifp);
472
473 if (ret_id != NULL)
474 *ret_id = zoneid;
475
476 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6))
477 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
478
479 return (0);
480}
481
482/*
483 * Just clear the embedded scope identifier. Return 0 if the original address
484 * is intact; return non 0 if the address is modified.
485 */
486int
487in6_clearscope(struct in6_addr *in6)
488{
489 int modified = 0;
490
491 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
492 if (in6->s6_addr16[1] != 0)
493 modified = 1;
494 in6->s6_addr16[1] = 0;
495 }
496
497 return (modified);
498}