1 | /* |
2 | * Copyright (c) 2009-2013 Apple Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | |
29 | /* |
30 | * Copyright (C) 2000 WIDE Project. |
31 | * All rights reserved. |
32 | * |
33 | * Redistribution and use in source and binary forms, with or without |
34 | * modification, are permitted provided that the following conditions |
35 | * are met: |
36 | * 1. Redistributions of source code must retain the above copyright |
37 | * notice, this list of conditions and the following disclaimer. |
38 | * 2. Redistributions in binary form must reproduce the above copyright |
39 | * notice, this list of conditions and the following disclaimer in the |
40 | * documentation and/or other materials provided with the distribution. |
41 | * 3. Neither the name of the project nor the names of its contributors |
42 | * may be used to endorse or promote products derived from this software |
43 | * without specific prior written permission. |
44 | * |
45 | * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND |
46 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
47 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
48 | * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE |
49 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
50 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
51 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
52 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
53 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
54 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
55 | * SUCH DAMAGE. |
56 | */ |
57 | |
58 | #include <sys/param.h> |
59 | #include <sys/malloc.h> |
60 | #include <sys/mbuf.h> |
61 | #include <sys/socket.h> |
62 | #include <sys/systm.h> |
63 | #include <sys/queue.h> |
64 | #include <sys/syslog.h> |
65 | #include <sys/mcache.h> |
66 | |
67 | #include <net/route.h> |
68 | #include <net/if.h> |
69 | |
70 | #include <netinet/in.h> |
71 | |
72 | #include <netinet6/in6_var.h> |
73 | #include <netinet6/scope6_var.h> |
74 | |
75 | #ifdef ENABLE_DEFAULT_SCOPE |
76 | int ip6_use_defzone = 1; |
77 | #else |
78 | int ip6_use_defzone = 0; |
79 | #endif |
80 | |
81 | decl_lck_mtx_data(static, scope6_lock); |
82 | static struct scope6_id sid_default; |
83 | |
84 | #define SID(ifp) &IN6_IFEXTRA(ifp)->scope6_id |
85 | |
86 | void |
87 | scope6_init(lck_grp_t *grp, lck_attr_t *attr) |
88 | { |
89 | bzero(&sid_default, sizeof(sid_default)); |
90 | lck_mtx_init(&scope6_lock, grp, attr); |
91 | } |
92 | |
93 | void |
94 | scope6_ifattach(struct ifnet *ifp) |
95 | { |
96 | struct scope6_id *sid; |
97 | |
98 | VERIFY(IN6_IFEXTRA(ifp) != NULL); |
99 | if_inet6data_lock_exclusive(ifp); |
100 | sid = SID(ifp); |
101 | /* N.B.: the structure is already zero'ed */ |
102 | /* |
103 | * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. |
104 | * Should we rather hardcode here? |
105 | */ |
106 | sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; |
107 | sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; |
108 | #if MULTI_SCOPE |
109 | /* by default, we don't care about scope boundary for these scopes. */ |
110 | sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; |
111 | sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; |
112 | #endif |
113 | if_inet6data_lock_done(ifp); |
114 | } |
115 | |
116 | /* |
117 | * Get a scope of the address. Node-local, link-local, site-local or global. |
118 | */ |
119 | int |
120 | in6_addrscope(struct in6_addr *addr) |
121 | { |
122 | int scope; |
123 | |
124 | if (addr->s6_addr8[0] == 0xfe) { |
125 | scope = addr->s6_addr8[1] & 0xc0; |
126 | |
127 | switch (scope) { |
128 | case 0x80: |
129 | return (IPV6_ADDR_SCOPE_LINKLOCAL); |
130 | case 0xc0: |
131 | return (IPV6_ADDR_SCOPE_SITELOCAL); |
132 | default: |
133 | return (IPV6_ADDR_SCOPE_GLOBAL); /* just in case */ |
134 | } |
135 | } |
136 | |
137 | if (addr->s6_addr8[0] == 0xff) { |
138 | scope = addr->s6_addr8[1] & 0x0f; |
139 | |
140 | /* |
141 | * due to other scope such as reserved, |
142 | * return scope doesn't work. |
143 | */ |
144 | switch (scope) { |
145 | case IPV6_ADDR_SCOPE_INTFACELOCAL: |
146 | return (IPV6_ADDR_SCOPE_INTFACELOCAL); |
147 | case IPV6_ADDR_SCOPE_LINKLOCAL: |
148 | return (IPV6_ADDR_SCOPE_LINKLOCAL); |
149 | case IPV6_ADDR_SCOPE_SITELOCAL: |
150 | return (IPV6_ADDR_SCOPE_SITELOCAL); |
151 | default: |
152 | return (IPV6_ADDR_SCOPE_GLOBAL); |
153 | } |
154 | } |
155 | |
156 | /* |
157 | * Regard loopback and unspecified addresses as global, since |
158 | * they have no ambiguity. |
159 | */ |
160 | if (bcmp(&in6addr_loopback, addr, sizeof (*addr) - 1) == 0) { |
161 | if (addr->s6_addr8[15] == 1) /* loopback */ |
162 | return (IPV6_ADDR_SCOPE_LINKLOCAL); |
163 | if (addr->s6_addr8[15] == 0) /* unspecified */ |
164 | return (IPV6_ADDR_SCOPE_GLOBAL); /* XXX: correct? */ |
165 | } |
166 | |
167 | return (IPV6_ADDR_SCOPE_GLOBAL); |
168 | } |
169 | |
170 | int |
171 | in6_addr2scopeid(struct ifnet *ifp, struct in6_addr *addr) |
172 | { |
173 | int scope = in6_addrscope(addr); |
174 | int retid = 0; |
175 | struct scope6_id *sid; |
176 | |
177 | if_inet6data_lock_shared(ifp); |
178 | if (IN6_IFEXTRA(ifp) == NULL) |
179 | goto err; |
180 | sid = SID(ifp); |
181 | switch (scope) { |
182 | case IPV6_ADDR_SCOPE_NODELOCAL: |
183 | retid = -1; /* XXX: is this an appropriate value? */ |
184 | break; |
185 | case IPV6_ADDR_SCOPE_LINKLOCAL: |
186 | retid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; |
187 | break; |
188 | case IPV6_ADDR_SCOPE_SITELOCAL: |
189 | retid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; |
190 | break; |
191 | case IPV6_ADDR_SCOPE_ORGLOCAL: |
192 | retid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; |
193 | break; |
194 | default: |
195 | break; /* XXX: value 0, treat as global. */ |
196 | } |
197 | err: |
198 | if_inet6data_lock_done(ifp); |
199 | |
200 | return (retid); |
201 | } |
202 | |
203 | /* |
204 | * Validate the specified scope zone ID in the sin6_scope_id field. If the ID |
205 | * is unspecified (=0), needs to be specified, and the default zone ID can be |
206 | * used, the default value will be used. |
207 | * This routine then generates the kernel-internal form: if the address scope |
208 | * of is interface-local or link-local, embed the interface index in the |
209 | * address. |
210 | */ |
211 | int |
212 | sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) |
213 | { |
214 | struct ifnet *ifp; |
215 | u_int32_t zoneid; |
216 | |
217 | if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) |
218 | zoneid = scope6_addr2default(&sin6->sin6_addr); |
219 | |
220 | if (zoneid != 0 && |
221 | (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || |
222 | IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { |
223 | /* |
224 | * At this moment, we only check interface-local and |
225 | * link-local scope IDs, and use interface indices as the |
226 | * zone IDs assuming a one-to-one mapping between interfaces |
227 | * and links. |
228 | */ |
229 | if (if_index < zoneid) |
230 | return (ENXIO); |
231 | ifnet_head_lock_shared(); |
232 | ifp = ifindex2ifnet[zoneid]; |
233 | if (ifp == NULL) { /* XXX: this can happen for some OS */ |
234 | ifnet_head_done(); |
235 | return (ENXIO); |
236 | } |
237 | ifnet_head_done(); |
238 | /* XXX assignment to 16bit from 32bit variable */ |
239 | sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); |
240 | |
241 | sin6->sin6_scope_id = 0; |
242 | } |
243 | |
244 | return (0); |
245 | } |
246 | |
247 | void |
248 | rtkey_to_sa6(struct rtentry *rt, struct sockaddr_in6 *sin6) |
249 | { |
250 | VERIFY(rt_key(rt)->sa_family == AF_INET6); |
251 | |
252 | *sin6 = *((struct sockaddr_in6 *)(void *)rt_key(rt)); |
253 | sin6->sin6_scope_id = 0; |
254 | } |
255 | |
256 | void |
257 | rtgw_to_sa6(struct rtentry *rt, struct sockaddr_in6 *sin6) |
258 | { |
259 | VERIFY(rt->rt_flags & RTF_GATEWAY); |
260 | |
261 | *sin6 = *((struct sockaddr_in6 *)(void *)rt->rt_gateway); |
262 | sin6->sin6_scope_id = 0; |
263 | } |
264 | |
265 | /* |
266 | * generate standard sockaddr_in6 from embedded form. |
267 | */ |
268 | int |
269 | sa6_recoverscope(struct sockaddr_in6 *sin6, boolean_t attachcheck) |
270 | { |
271 | u_int32_t zoneid; |
272 | |
273 | if (sin6->sin6_scope_id != 0) { |
274 | log(LOG_NOTICE, |
275 | "sa6_recoverscope: assumption failure (non 0 ID): %s%%%d\n" , |
276 | ip6_sprintf(&sin6->sin6_addr), sin6->sin6_scope_id); |
277 | /* XXX: proceed anyway... */ |
278 | } |
279 | if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || |
280 | IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { |
281 | /* |
282 | * KAME assumption: link id == interface id |
283 | */ |
284 | zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); |
285 | if (zoneid) { |
286 | /* sanity check */ |
287 | if (if_index < zoneid) |
288 | return (ENXIO); |
289 | /* |
290 | * We use the attachcheck parameter to skip the |
291 | * interface attachment check. |
292 | * Some callers might hold the ifnet_head lock in |
293 | * exclusive mode. This means that: |
294 | * 1) the interface can't go away -- hence we don't |
295 | * need to perform this check |
296 | * 2) we can't perform this check because the lock is |
297 | * in exclusive mode and trying to lock it in shared |
298 | * mode would cause a deadlock. |
299 | */ |
300 | if (attachcheck) { |
301 | ifnet_head_lock_shared(); |
302 | if (ifindex2ifnet[zoneid] == NULL) { |
303 | ifnet_head_done(); |
304 | return (ENXIO); |
305 | } |
306 | ifnet_head_done(); |
307 | } |
308 | sin6->sin6_addr.s6_addr16[1] = 0; |
309 | sin6->sin6_scope_id = zoneid; |
310 | } |
311 | } |
312 | |
313 | return (0); |
314 | } |
315 | |
316 | void |
317 | scope6_setdefault(struct ifnet *ifp) |
318 | { |
319 | /* |
320 | * Currently, this function just set the default "link" according to |
321 | * the given interface. |
322 | * We might eventually have to separate the notion of "link" from |
323 | * "interface" and provide a user interface to set the default. |
324 | */ |
325 | lck_mtx_lock(&scope6_lock); |
326 | if (ifp != NULL) { |
327 | sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = |
328 | ifp->if_index; |
329 | sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = |
330 | ifp->if_index; |
331 | } else { |
332 | sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; |
333 | sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; |
334 | } |
335 | lck_mtx_unlock(&scope6_lock); |
336 | } |
337 | |
338 | |
339 | u_int32_t |
340 | scope6_addr2default(struct in6_addr *addr) |
341 | { |
342 | u_int32_t id = 0; |
343 | int index = in6_addrscope(addr); |
344 | |
345 | /* |
346 | * special case: The loopback address should be considered as |
347 | * link-local, but there's no ambiguity in the syntax. |
348 | */ |
349 | if (IN6_IS_ADDR_LOOPBACK(addr)) |
350 | return (0); |
351 | |
352 | lck_mtx_lock(&scope6_lock); |
353 | id = sid_default.s6id_list[index]; |
354 | lck_mtx_unlock(&scope6_lock); |
355 | |
356 | return (id); |
357 | } |
358 | |
359 | /* |
360 | * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is |
361 | * non NULL, it is set to the zone ID. If the zone ID needs to be embedded |
362 | * in the in6_addr structure, in6 will be modified. |
363 | * |
364 | * ret_id - unnecessary? |
365 | */ |
366 | int |
367 | in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) |
368 | { |
369 | int scope; |
370 | u_int32_t zoneid = 0; |
371 | struct scope6_id *sid; |
372 | |
373 | /* |
374 | * special case: the loopback address can only belong to a loopback |
375 | * interface. |
376 | */ |
377 | if (IN6_IS_ADDR_LOOPBACK(in6)) { |
378 | if (!(ifp->if_flags & IFF_LOOPBACK)) { |
379 | return (EINVAL); |
380 | } else { |
381 | if (ret_id != NULL) |
382 | *ret_id = 0; /* there's no ambiguity */ |
383 | return (0); |
384 | } |
385 | } |
386 | |
387 | scope = in6_addrscope(in6); |
388 | |
389 | if_inet6data_lock_shared(ifp); |
390 | if (IN6_IFEXTRA(ifp) == NULL) { |
391 | if_inet6data_lock_done(ifp); |
392 | if (ret_id) |
393 | *ret_id = 0; |
394 | return (EINVAL); |
395 | } |
396 | sid = SID(ifp); |
397 | switch (scope) { |
398 | case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ |
399 | zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; |
400 | break; |
401 | |
402 | case IPV6_ADDR_SCOPE_LINKLOCAL: |
403 | zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; |
404 | break; |
405 | |
406 | case IPV6_ADDR_SCOPE_SITELOCAL: |
407 | zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; |
408 | break; |
409 | |
410 | case IPV6_ADDR_SCOPE_ORGLOCAL: |
411 | zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; |
412 | break; |
413 | default: |
414 | zoneid = 0; /* XXX: treat as global. */ |
415 | break; |
416 | } |
417 | if_inet6data_lock_done(ifp); |
418 | |
419 | if (ret_id != NULL) |
420 | *ret_id = zoneid; |
421 | |
422 | if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) |
423 | in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ |
424 | |
425 | return (0); |
426 | } |
427 | |
428 | /* |
429 | * Just clear the embedded scope identifier. Return 0 if the original address |
430 | * is intact; return non 0 if the address is modified. |
431 | */ |
432 | int |
433 | in6_clearscope(struct in6_addr *in6) |
434 | { |
435 | int modified = 0; |
436 | |
437 | if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { |
438 | if (in6->s6_addr16[1] != 0) |
439 | modified = 1; |
440 | in6->s6_addr16[1] = 0; |
441 | } |
442 | |
443 | return (modified); |
444 | } |
445 | |