xref: /dragonfly/sys/netinet6/scope6.c (revision cfd1aba3)
1 /*	$FreeBSD: src/sys/netinet6/scope6.c,v 1.1.2.3 2002/04/01 15:29:04 ume Exp $	*/
2 /*	$DragonFly: src/sys/netinet6/scope6.c,v 1.11 2008/01/05 14:02:40 swildner Exp $	*/
3 /*	$KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $	*/
4 
5 /*
6  * Copyright (C) 2000 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/malloc.h>
36 #include <sys/mbuf.h>
37 #include <sys/socket.h>
38 #include <sys/systm.h>
39 #include <sys/queue.h>
40 #include <sys/thread2.h>
41 
42 #include <net/route.h>
43 #include <net/if.h>
44 
45 #include <netinet/in.h>
46 
47 #include <netinet6/in6_var.h>
48 #include <netinet6/scope6_var.h>
49 
50 static struct scope6_id sid_default;
51 
52 static __inline
53 struct scope6_id *
54 SID(struct ifnet *ifp)
55 {
56 	struct in6_ifextra *xtra;
57 
58 	xtra = ifp->if_afdata[AF_INET6];
59 	if (xtra)
60 		return (xtra->scope6_id);
61 	return(NULL);
62 }
63 
64 void
65 scope6_init(void)
66 {
67 	bzero(&sid_default, sizeof(sid_default));
68 }
69 
70 struct scope6_id *
71 scope6_ifattach(struct ifnet *ifp)
72 {
73 	struct scope6_id *sid;
74 
75 	sid = (struct scope6_id *)kmalloc(sizeof(*sid), M_IFADDR,
76 	    M_WAITOK | M_ZERO);
77 
78 	crit_enter();
79 
80 	/*
81 	 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
82 	 * Should we rather hardcode here?
83 	 */
84 	sid->s6id_list[IPV6_ADDR_SCOPE_NODELOCAL] = ifp->if_index;
85 	sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
86 #ifdef MULTI_SCOPE
87 	/* by default, we don't care about scope boundary for these scopes. */
88 	sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1;
89 	sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1;
90 #endif
91 
92 	crit_exit();
93 	return sid;
94 }
95 
96 void
97 scope6_ifdetach(struct scope6_id *sid)
98 {
99 	kfree(sid, M_IFADDR);
100 }
101 
102 int
103 scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
104 {
105 	int i;
106 	int error = 0;
107 	struct scope6_id *sid = SID(ifp);
108 
109 	if (!sid)	/* paranoid? */
110 		return (EINVAL);
111 
112 	/*
113 	 * XXX: We need more consistency checks of the relationship among
114 	 * scopes (e.g. an organization should be larger than a site).
115 	 */
116 
117 	/*
118 	 * TODO(XXX): after setting, we should reflect the changes to
119 	 * interface addresses, routing table entries, PCB entries...
120 	 */
121 
122 	crit_enter();
123 
124 	for (i = 0; i < 16; i++) {
125 		if (idlist->s6id_list[i] &&
126 		    idlist->s6id_list[i] != sid->s6id_list[i]) {
127 			if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
128 			    idlist->s6id_list[i] > if_index) {
129 				/*
130 				 * XXX: theoretically, there should be no
131 				 * relationship between link IDs and interface
132 				 * IDs, but we check the consistency for
133 				 * safety in later use.
134 				 */
135 				crit_exit();
136 				return (EINVAL);
137 			}
138 
139 			/*
140 			 * XXX: we must need lots of work in this case,
141 			 * but we simply set the new value in this initial
142 			 * implementation.
143 			 */
144 			sid->s6id_list[i] = idlist->s6id_list[i];
145 		}
146 	}
147 	crit_exit();
148 
149 	return (error);
150 }
151 
152 int
153 scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
154 {
155 	struct scope6_id *sid = SID(ifp);
156 
157 	if (sid == NULL)	/* paranoid? */
158 		return (EINVAL);
159 
160 	*idlist = *sid;
161 
162 	return (0);
163 }
164 
165 
166 /*
167  * Get a scope of the address. Node-local, link-local, site-local or global.
168  */
169 int
170 in6_addrscope(struct in6_addr *addr)
171 {
172 	int scope;
173 
174 	if (addr->s6_addr8[0] == 0xfe) {
175 		scope = addr->s6_addr8[1] & 0xc0;
176 
177 		switch (scope) {
178 		case 0x80:
179 			return IPV6_ADDR_SCOPE_LINKLOCAL;
180 			break;
181 		case 0xc0:
182 			return IPV6_ADDR_SCOPE_SITELOCAL;
183 			break;
184 		default:
185 			return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
186 			break;
187 		}
188 	}
189 
190 
191 	if (addr->s6_addr8[0] == 0xff) {
192 		scope = addr->s6_addr8[1] & 0x0f;
193 
194 		/*
195 		 * due to other scope such as reserved,
196 		 * return scope doesn't work.
197 		 */
198 		switch (scope) {
199 		case IPV6_ADDR_SCOPE_NODELOCAL:
200 			return IPV6_ADDR_SCOPE_NODELOCAL;
201 			break;
202 		case IPV6_ADDR_SCOPE_LINKLOCAL:
203 			return IPV6_ADDR_SCOPE_LINKLOCAL;
204 			break;
205 		case IPV6_ADDR_SCOPE_SITELOCAL:
206 			return IPV6_ADDR_SCOPE_SITELOCAL;
207 			break;
208 		default:
209 			return IPV6_ADDR_SCOPE_GLOBAL;
210 			break;
211 		}
212 	}
213 
214 	if (bcmp(&kin6addr_loopback, addr, sizeof(*addr) - 1) == 0) {
215 		if (addr->s6_addr8[15] == 1) /* loopback */
216 			return IPV6_ADDR_SCOPE_NODELOCAL;
217 		if (addr->s6_addr8[15] == 0) /* unspecified */
218 			return IPV6_ADDR_SCOPE_LINKLOCAL;
219 	}
220 
221 	return IPV6_ADDR_SCOPE_GLOBAL;
222 }
223 
224 int
225 in6_addr2scopeid(struct ifnet *ifp,	/* must not be NULL */
226 		 struct in6_addr *addr)	/* must not be NULL */
227 {
228 	int scope;
229 	struct scope6_id *sid = SID(ifp);
230 
231 #ifdef DIAGNOSTIC
232 	if (sid == NULL) { /* should not happen */
233 		panic("in6_addr2zoneid: scope array is NULL");
234 		/* NOTREACHED */
235 	}
236 #endif
237 
238 	/*
239 	 * special case: the loopback address can only belong to a loopback
240 	 * interface.
241 	 */
242 	if (IN6_IS_ADDR_LOOPBACK(addr)) {
243 		if (!(ifp->if_flags & IFF_LOOPBACK))
244 			return (-1);
245 		else
246 			return (0); /* there's no ambiguity */
247 	}
248 
249 	scope = in6_addrscope(addr);
250 
251 	switch(scope) {
252 	case IPV6_ADDR_SCOPE_NODELOCAL:
253 		return (-1);	/* XXX: is this an appropriate value? */
254 
255 	case IPV6_ADDR_SCOPE_LINKLOCAL:
256 		return (sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]);
257 
258 	case IPV6_ADDR_SCOPE_SITELOCAL:
259 		return (sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]);
260 
261 	case IPV6_ADDR_SCOPE_ORGLOCAL:
262 		return (sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]);
263 
264 	default:
265 		return (0);	/* XXX: treat as global. */
266 	}
267 }
268 
269 void
270 scope6_setdefault(struct ifnet *ifp)	/* note that this might be NULL */
271 {
272 	/*
273 	 * Currently, this function just set the default "interfaces"
274 	 * and "links" according to the given interface.
275 	 * We might eventually have to separate the notion of "link" from
276 	 * "interface" and provide a user interface to set the default.
277 	 */
278 	if (ifp) {
279 		sid_default.s6id_list[IPV6_ADDR_SCOPE_NODELOCAL] =
280 			ifp->if_index;
281 		sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
282 			ifp->if_index;
283 	} else {
284 		sid_default.s6id_list[IPV6_ADDR_SCOPE_NODELOCAL] = 0;
285 		sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
286 	}
287 }
288 
289 int
290 scope6_get_default(struct scope6_id *idlist)
291 {
292 	*idlist = sid_default;
293 
294 	return (0);
295 }
296 
297 u_int32_t
298 scope6_addr2default(struct in6_addr *addr)
299 {
300 	/*
301 	 * special case: The loopback address should be considered as
302 	 * link-local, but there's no ambiguity in the syntax.
303 	 */
304 	if (IN6_IS_ADDR_LOOPBACK(addr))
305 		return (0);
306 
307 	return (sid_default.s6id_list[in6_addrscope(addr)]);
308 }
309 
310 /*
311  * Determine the appropriate scope zone ID for in6 and ifp.  If ret_id is
312  * non NULL, it is set to the zone ID.  If the zone ID needs to be embedded
313   * in the in6_addr structure, in6 will be modified.
314  */
315 int
316 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
317 {
318 	int scope;
319 	u_int32_t zoneid = 0;
320 	struct scope6_id *sid;
321 
322 	ifnet_serialize_all(ifp);
323 
324 	sid = SID(ifp);
325 
326 #ifdef DIAGNOSTIC
327 	if (sid == NULL) { /* should not happen */
328 		panic("in6_setscope: scope array is NULL");
329 		/* NOTREACHED */
330 	}
331 #endif
332 
333 	/*
334 	 * special case: the loopback address can only belong to a loopback
335 	 * interface.
336 	 */
337 	if (IN6_IS_ADDR_LOOPBACK(in6)) {
338 		if (!(ifp->if_flags & IFF_LOOPBACK)) {
339 			ifnet_deserialize_all(ifp);
340 			return (EINVAL);
341 		} else {
342 			if (ret_id != NULL)
343 				*ret_id = 0; /* there's no ambiguity */
344 			ifnet_deserialize_all(ifp);
345 			return (0);
346 		}
347 	}
348 
349 	scope = in6_addrscope(in6);
350 
351 	switch (scope) {
352 	case IPV6_ADDR_SCOPE_NODELOCAL: /* should be interface index */
353 		zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_NODELOCAL];
354 		break;
355 
356 	case IPV6_ADDR_SCOPE_LINKLOCAL:
357 		zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL];
358 		break;
359 
360 	case IPV6_ADDR_SCOPE_SITELOCAL:
361 		zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL];
362 		break;
363 
364 	case IPV6_ADDR_SCOPE_ORGLOCAL:
365 		zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL];
366 		break;
367 
368 	default:
369 		zoneid = 0;     /* XXX: treat as global. */
370 		break;
371 	}
372 
373 	ifnet_deserialize_all(ifp);
374 
375 	if (ret_id != NULL)
376 		*ret_id = zoneid;
377 
378 	if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_NODELOCAL(in6) )
379 		in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
380 
381 	return (0);
382 }
383