xref: /netbsd/sys/netinet6/in6_pcb.c (revision bf9ec67e)
1 /*	$NetBSD: in6_pcb.c,v 1.48 2002/05/28 11:10:53 itojun Exp $	*/
2 /*	$KAME: in6_pcb.c,v 1.84 2001/02/08 18:02:08 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1982, 1986, 1991, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Berkeley and its contributors.
49  * 4. Neither the name of the University nor the names of its contributors
50  *    may be used to endorse or promote products derived from this software
51  *    without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  *	@(#)in_pcb.c	8.2 (Berkeley) 1/4/94
66  */
67 
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "$NetBSD: in6_pcb.c,v 1.48 2002/05/28 11:10:53 itojun Exp $");
70 
71 #include "opt_ipsec.h"
72 
73 #include <sys/param.h>
74 #include <sys/systm.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/protosw.h>
78 #include <sys/socket.h>
79 #include <sys/socketvar.h>
80 #include <sys/ioctl.h>
81 #include <sys/errno.h>
82 #include <sys/time.h>
83 #include <sys/proc.h>
84 
85 #include <net/if.h>
86 #include <net/route.h>
87 
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet/in_systm.h>
91 #include <netinet/ip.h>
92 #include <netinet/in_pcb.h>
93 #include <netinet/ip6.h>
94 #include <netinet6/ip6_var.h>
95 #include <netinet6/in6_pcb.h>
96 #include <netinet6/nd6.h>
97 
98 #include "loop.h"
99 extern struct ifnet loif[NLOOP];
100 #include "faith.h"
101 
102 #ifdef IPSEC
103 #include <netinet6/ipsec.h>
104 #include <netkey/key.h>
105 #endif /* IPSEC */
106 
107 struct in6_addr zeroin6_addr;
108 
109 int ip6_anonportmin = IPV6PORT_ANONMIN;
110 int ip6_anonportmax = IPV6PORT_ANONMAX;
111 int ip6_lowportmin  = IPV6PORT_RESERVEDMIN;
112 int ip6_lowportmax  = IPV6PORT_RESERVEDMAX;
113 
114 int
115 in6_pcballoc(so, head)
116 	struct socket *so;
117 	struct in6pcb *head;
118 {
119 	struct in6pcb *in6p;
120 	int s;
121 #ifdef IPSEC
122 	int error;
123 #endif
124 
125 	MALLOC(in6p, struct in6pcb *, sizeof(*in6p), M_PCB, M_NOWAIT);
126 	if (in6p == NULL)
127 		return(ENOBUFS);
128 	bzero((caddr_t)in6p, sizeof(*in6p));
129 	in6p->in6p_head = head;
130 	in6p->in6p_socket = so;
131 	in6p->in6p_hops = -1;	/* use kernel default */
132 	in6p->in6p_icmp6filt = NULL;
133 #ifdef IPSEC
134 	error = ipsec_init_policy(so, &in6p->in6p_sp);
135 	if (error != 0) {
136 		FREE(in6p, M_PCB);
137 		return error;
138 	}
139 #endif /* IPSEC */
140 	s = splnet();
141 	in6p->in6p_next = head->in6p_next;
142 	head->in6p_next = in6p;
143 	in6p->in6p_prev = head;
144 	in6p->in6p_next->in6p_prev = in6p;
145 	splx(s);
146 	if (ip6_v6only)
147 		in6p->in6p_flags |= IN6P_IPV6_V6ONLY;
148 	so->so_pcb = (caddr_t)in6p;
149 	return(0);
150 }
151 
152 int
153 in6_pcbbind(in6p, nam, p)
154 	struct in6pcb *in6p;
155 	struct mbuf *nam;
156 	struct proc *p;
157 {
158 	struct socket *so = in6p->in6p_socket;
159 	struct in6pcb *head = in6p->in6p_head;
160 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)NULL;
161 	u_int16_t lport = 0;
162 	int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);
163 
164 	if (in6p->in6p_lport || !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
165 		return(EINVAL);
166 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 &&
167 	   ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
168 	    (so->so_options & SO_ACCEPTCONN) == 0))
169 		wild = IN6PLOOKUP_WILDCARD;
170 	if (nam) {
171 		sin6 = mtod(nam, struct sockaddr_in6 *);
172 		if (nam->m_len != sizeof(*sin6))
173 			return(EINVAL);
174 		/*
175 		 * We should check the family, but old programs
176 		 * incorrectly fail to intialize it.
177 		 */
178 		if (sin6->sin6_family != AF_INET6)
179 			return(EAFNOSUPPORT);
180 
181 		/*
182 		 * since we do not check port number duplicate with IPv4 space,
183 		 * we reject it at this moment.  If we leave it, we would
184 		 * mistakenly allow normal users to hijack tcp/udp ports from
185 		 * other users.
186 		 */
187 		if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
188 			return(EADDRNOTAVAIL);
189 
190 		/* KAME hack: embed scopeid */
191 		if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL) != 0)
192 			return EINVAL;
193 		/* this must be cleared for ifa_ifwithaddr() */
194 		sin6->sin6_scope_id = 0;
195 
196 		lport = sin6->sin6_port;
197 		if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
198 			/*
199 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
200 			 * allow compepte duplication of binding if
201 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
202 			 * and a multicast address is bound on both
203 			 * new and duplicated sockets.
204 			 */
205 			if (so->so_options & SO_REUSEADDR)
206 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
207 		}
208 		else if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
209 			struct sockaddr_in sin;
210 
211 			bzero(&sin, sizeof(sin));
212 			sin.sin_len = sizeof(sin);
213 			sin.sin_family = AF_INET;
214 			bcopy(&sin6->sin6_addr.s6_addr32[3], &sin.sin_addr,
215 				sizeof(sin.sin_addr));
216 			if (ifa_ifwithaddr((struct sockaddr *)&sin) == 0)
217 				return EADDRNOTAVAIL;
218 		}
219 		else if (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
220 			struct ifaddr *ia = NULL;
221 
222 			sin6->sin6_port = 0;		/* yech... */
223 			if ((in6p->in6p_flags & IN6P_FAITH) == 0 &&
224 			    (ia = ifa_ifwithaddr((struct sockaddr *)sin6)) == 0)
225 				return(EADDRNOTAVAIL);
226 
227 			/*
228 			 * bind to an anycast address might accidentally
229 			 * cause sending a packet with an anycast source
230 			 * address, so we forbid it.
231 			 */
232 			if (ia &&
233 			    ((struct in6_ifaddr *)ia)->ia6_flags &
234 			    (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY|
235 			     IN6_IFF_DETACHED|IN6_IFF_DEPRECATED)) {
236 				return(EADDRNOTAVAIL);
237 			}
238 		}
239 		if (lport) {
240 #ifndef IPNOPRIVPORTS
241 			int priv;
242 
243 			/*
244 			 * NOTE: all operating systems use suser() for
245 			 * privilege check!  do not rewrite it into SS_PRIV.
246 			 */
247 			priv = (p && !suser(p->p_ucred, &p->p_acflag)) ? 1 : 0;
248 			/* GROSS */
249 			if (ntohs(lport) < IPV6PORT_RESERVED && !priv)
250 				return(EACCES);
251 #endif
252 
253 			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
254 				/* should check this but we can't ... */
255 #if 0
256 				struct inpcb *t;
257 
258 				t = in_pcblookup_bind(&tcbtable,
259 					(struct in_addr *)&sin6->sin6_addr.s6_addr32[3],
260 					lport);
261 				if (t && (reuseport & t->inp_socket->so_options) == 0)
262 					return EADDRINUSE;
263 #endif
264 			} else
265 			{
266 				struct in6pcb *t;
267 
268 				t = in6_pcblookup(head, &zeroin6_addr, 0,
269 						  &sin6->sin6_addr, lport, wild);
270 				if (t && (reuseport & t->in6p_socket->so_options) == 0)
271 					return(EADDRINUSE);
272 			}
273 		}
274 		in6p->in6p_laddr = sin6->sin6_addr;
275 	}
276 
277 	if (lport == 0) {
278 		int e;
279 		if ((e = in6_pcbsetport(&in6p->in6p_laddr, in6p)) != 0)
280 			return(e);
281 	}
282 	else
283 		in6p->in6p_lport = lport;
284 
285 	in6p->in6p_flowinfo = sin6 ? sin6->sin6_flowinfo : 0;	/*XXX*/
286 	return(0);
287 }
288 
289 /*
290  * Connect from a socket to a specified address.
291  * Both address and port must be specified in argument sin6.
292  * If don't have a local address for this socket yet,
293  * then pick one.
294  */
295 int
296 in6_pcbconnect(in6p, nam)
297 	struct in6pcb *in6p;
298 	struct mbuf *nam;
299 {
300 	struct in6_addr *in6a = NULL;
301 	struct sockaddr_in6 *sin6 = mtod(nam, struct sockaddr_in6 *);
302 	struct ifnet *ifp = NULL;	/* outgoing interface */
303 	int error = 0;
304 #ifdef INET
305 	struct in6_addr mapped;
306 #endif
307 	struct sockaddr_in6 tmp;
308 
309 	(void)&in6a;				/* XXX fool gcc */
310 
311 	if (nam->m_len != sizeof(*sin6))
312 		return(EINVAL);
313 	if (sin6->sin6_family != AF_INET6)
314 		return(EAFNOSUPPORT);
315 	if (sin6->sin6_port == 0)
316 		return(EADDRNOTAVAIL);
317 
318 	/* sanity check for mapped address case */
319 	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
320 		if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY) != 0)
321 			return EINVAL;
322 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
323 			in6p->in6p_laddr.s6_addr16[5] = htons(0xffff);
324 		if (!IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr))
325 			return EINVAL;
326 	} else
327 	{
328 		if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr))
329 			return EINVAL;
330 	}
331 
332 	/* protect *sin6 from overwrites */
333 	tmp = *sin6;
334 	sin6 = &tmp;
335 
336 	/* KAME hack: embed scopeid */
337 	if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, &ifp) != 0)
338 		return EINVAL;
339 
340 	/* Source address selection. */
341 	if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)
342 	 && in6p->in6p_laddr.s6_addr32[3] == 0) {
343 #ifdef INET
344 		struct sockaddr_in sin, *sinp;
345 
346 		bzero(&sin, sizeof(sin));
347 		sin.sin_len = sizeof(sin);
348 		sin.sin_family = AF_INET;
349 		bcopy(&sin6->sin6_addr.s6_addr32[3], &sin.sin_addr,
350 			sizeof(sin.sin_addr));
351 		sinp = in_selectsrc(&sin, (struct route *)&in6p->in6p_route,
352 			in6p->in6p_socket->so_options, NULL, &error);
353 		if (sinp == 0) {
354 			if (error == 0)
355 				error = EADDRNOTAVAIL;
356 			return(error);
357 		}
358 		bzero(&mapped, sizeof(mapped));
359 		mapped.s6_addr16[5] = htons(0xffff);
360 		bcopy(&sinp->sin_addr, &mapped.s6_addr32[3], sizeof(sinp->sin_addr));
361 		in6a = &mapped;
362 #else
363 		return EADDRNOTAVAIL;
364 #endif
365 	} else
366 	{
367 		/*
368 		 * XXX: in6_selectsrc might replace the bound local address
369 		 * with the address specified by setsockopt(IPV6_PKTINFO).
370 		 * Is it the intended behavior?
371 		 */
372 		in6a = in6_selectsrc(sin6, in6p->in6p_outputopts,
373 				     in6p->in6p_moptions,
374 				     &in6p->in6p_route,
375 				     &in6p->in6p_laddr, &error);
376 		if (in6a == 0) {
377 			if (error == 0)
378 				error = EADDRNOTAVAIL;
379 			return(error);
380 		}
381 	}
382 	if (in6p->in6p_route.ro_rt)
383 		ifp = in6p->in6p_route.ro_rt->rt_ifp;
384 
385 	in6p->in6p_ip6.ip6_hlim = (u_int8_t)in6_selecthlim(in6p, ifp);
386 
387 	if (in6_pcblookup(in6p->in6p_head,
388 			 &sin6->sin6_addr,
389 			 sin6->sin6_port,
390 			 IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) ?
391 			  in6a : &in6p->in6p_laddr,
392 			 in6p->in6p_lport,
393 			 0))
394 		return(EADDRINUSE);
395 	if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)
396 	 || (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)
397 	  && in6p->in6p_laddr.s6_addr32[3] == 0))
398 	{
399 		/*
400 		 * XXX in IPv4 mapped address case, we should grab fresh
401 		 * local port number by in_pcbbind, not in6_pcbbind.
402 		 * if we are in bad luck, we may assign conflicting port number
403 		 * between IPv4 and IPv6 unwillingly.
404 		 */
405 		if (in6p->in6p_lport == 0) {
406 			(void)in6_pcbbind(in6p, (struct mbuf *)0,
407 			    (struct proc *)0);
408 		}
409 		in6p->in6p_laddr = *in6a;
410 	}
411 	in6p->in6p_faddr = sin6->sin6_addr;
412 	in6p->in6p_fport = sin6->sin6_port;
413 	/*
414 	 * xxx kazu flowlabel is necessary for connect?
415 	 * but if this line is missing, the garbage value remains.
416 	 */
417 	in6p->in6p_flowinfo = sin6->sin6_flowinfo;
418 #ifdef IPSEC
419 	if (in6p->in6p_socket->so_type == SOCK_STREAM)
420 		ipsec_pcbconn(in6p->in6p_sp);
421 #endif
422 	return(0);
423 }
424 
425 void
426 in6_pcbdisconnect(in6p)
427 	struct in6pcb *in6p;
428 {
429 	bzero((caddr_t)&in6p->in6p_faddr, sizeof(in6p->in6p_faddr));
430 	in6p->in6p_fport = 0;
431 	if (in6p->in6p_socket->so_state & SS_NOFDREF)
432 		in6_pcbdetach(in6p);
433 #ifdef IPSEC
434 	ipsec_pcbdisconn(in6p->in6p_sp);
435 #endif
436 }
437 
438 void
439 in6_pcbdetach(in6p)
440 	struct in6pcb *in6p;
441 {
442 	struct socket *so = in6p->in6p_socket;
443 	int s;
444 
445 #ifdef IPSEC
446 	ipsec6_delete_pcbpolicy(in6p);
447 #endif /* IPSEC */
448 	sotoin6pcb(so) = 0;
449 	sofree(so);
450 	if (in6p->in6p_options)
451 		m_freem(in6p->in6p_options);
452 	if (in6p->in6p_outputopts) {
453 		if (in6p->in6p_outputopts->ip6po_rthdr &&
454 		    in6p->in6p_outputopts->ip6po_route.ro_rt)
455 			RTFREE(in6p->in6p_outputopts->ip6po_route.ro_rt);
456 		if (in6p->in6p_outputopts->ip6po_m)
457 			(void)m_free(in6p->in6p_outputopts->ip6po_m);
458 		free(in6p->in6p_outputopts, M_IP6OPT);
459 	}
460 	if (in6p->in6p_route.ro_rt)
461 		rtfree(in6p->in6p_route.ro_rt);
462 	ip6_freemoptions(in6p->in6p_moptions);
463 	s = splnet();
464 	in6p->in6p_next->in6p_prev = in6p->in6p_prev;
465 	in6p->in6p_prev->in6p_next = in6p->in6p_next;
466 	in6p->in6p_prev = NULL;
467 	splx(s);
468 	FREE(in6p, M_PCB);
469 }
470 
471 void
472 in6_setsockaddr(in6p, nam)
473 	struct in6pcb *in6p;
474 	struct mbuf *nam;
475 {
476 	struct sockaddr_in6 *sin6;
477 
478 	nam->m_len = sizeof(*sin6);
479 	sin6 = mtod(nam, struct sockaddr_in6 *);
480 	bzero((caddr_t)sin6, sizeof(*sin6));
481 	sin6->sin6_family = AF_INET6;
482 	sin6->sin6_len = sizeof(struct sockaddr_in6);
483 	sin6->sin6_port = in6p->in6p_lport;
484 	/* KAME hack: recover scopeid */
485 	(void)in6_recoverscope(sin6, &in6p->in6p_laddr, NULL);
486 }
487 
488 void
489 in6_setpeeraddr(in6p, nam)
490 	struct in6pcb *in6p;
491 	struct mbuf *nam;
492 {
493 	struct sockaddr_in6 *sin6;
494 
495 	nam->m_len = sizeof(*sin6);
496 	sin6 = mtod(nam, struct sockaddr_in6 *);
497 	bzero((caddr_t)sin6, sizeof(*sin6));
498 	sin6->sin6_family = AF_INET6;
499 	sin6->sin6_len = sizeof(struct sockaddr_in6);
500 	sin6->sin6_port = in6p->in6p_fport;
501 	/* KAME hack: recover scopeid */
502 	(void)in6_recoverscope(sin6, &in6p->in6p_faddr, NULL);
503 }
504 
505 /*
506  * Pass some notification to all connections of a protocol
507  * associated with address dst.  The local address and/or port numbers
508  * may be specified to limit the search.  The "usual action" will be
509  * taken, depending on the ctlinput cmd.  The caller must filter any
510  * cmds that are uninteresting (e.g., no error in the map).
511  * Call the protocol specific routine (if any) to report
512  * any errors for each matching socket.
513  *
514  * Must be called at splsoftnet.
515  *
516  * Note: src (4th arg) carries the flowlabel value on the original IPv6
517  * header, in sin6_flowinfo member.
518  */
519 int
520 in6_pcbnotify(head, dst, fport_arg, src, lport_arg, cmd, cmdarg, notify)
521 	struct in6pcb *head;
522 	struct sockaddr *dst, *src;
523 	u_int fport_arg, lport_arg;
524 	int cmd;
525 	void *cmdarg;
526 	void (*notify) __P((struct in6pcb *, int));
527 {
528 	struct in6pcb *in6p, *nin6p;
529 	struct sockaddr_in6 sa6_src, *sa6_dst;
530 	u_int16_t fport = fport_arg, lport = lport_arg;
531 	int errno;
532 	int nmatch = 0;
533 	u_int32_t flowinfo;
534 
535 	if ((unsigned)cmd > PRC_NCMDS || dst->sa_family != AF_INET6)
536 		return 0;
537 
538 	sa6_dst = (struct sockaddr_in6 *)dst;
539 	if (IN6_IS_ADDR_UNSPECIFIED(&sa6_dst->sin6_addr))
540 		return 0;
541 
542 	/*
543 	 * note that src can be NULL when we get notify by local fragmentation.
544 	 */
545 	sa6_src = (src == NULL) ? sa6_any : *(struct sockaddr_in6 *)src;
546 	flowinfo = sa6_src.sin6_flowinfo;
547 
548 	/*
549 	 * Redirects go to all references to the destination,
550 	 * and use in6_rtchange to invalidate the route cache.
551 	 * Dead host indications: also use in6_rtchange to invalidate
552 	 * the cache, and deliver the error to all the sockets.
553 	 * Otherwise, if we have knowledge of the local port and address,
554 	 * deliver only to that socket.
555 	 */
556 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
557 		fport = 0;
558 		lport = 0;
559 		bzero((caddr_t)&sa6_src.sin6_addr, sizeof(sa6_src.sin6_addr));
560 
561 		if (cmd != PRC_HOSTDEAD)
562 			notify = in6_rtchange;
563 	}
564 
565 	errno = inet6ctlerrmap[cmd];
566 	for (in6p = head->in6p_next; in6p != head; in6p = nin6p) {
567 		nin6p = in6p->in6p_next;
568 
569 		/*
570 		 * Under the following condition, notify of redirects
571 		 * to the pcb, without making address matches against inpcb.
572 		 * - redirect notification is arrived.
573 		 * - the inpcb is unconnected.
574 		 * - the inpcb is caching !RTF_HOST routing entry.
575 		 * - the ICMPv6 notification is from the gateway cached in the
576 		 *   inpcb.  i.e. ICMPv6 notification is from nexthop gateway
577 		 *   the inpcb used very recently.
578 		 *
579 		 * This is to improve interaction between netbsd/openbsd
580 		 * redirect handling code, and inpcb route cache code.
581 		 * without the clause, !RTF_HOST routing entry (which carries
582 		 * gateway used by inpcb right before the ICMPv6 redirect)
583 		 * will be cached forever in unconnected inpcb.
584 		 *
585 		 * There still is a question regarding to what is TRT:
586 		 * - On bsdi/freebsd, RTF_HOST (cloned) routing entry will be
587 		 *   generated on packet output.  inpcb will always cache
588 		 *   RTF_HOST routing entry so there's no need for the clause
589 		 *   (ICMPv6 redirect will update RTF_HOST routing entry,
590 		 *   and inpcb is caching it already).
591 		 *   However, bsdi/freebsd are vulnerable to local DoS attacks
592 		 *   due to the cloned routing entries.
593 		 * - Specwise, "destination cache" is mentioned in RFC2461.
594 		 *   Jinmei says that it implies bsdi/freebsd behavior, itojun
595 		 *   is not really convinced.
596 		 * - Having hiwat/lowat on # of cloned host route (redirect/
597 		 *   pmtud) may be a good idea.  netbsd/openbsd has it.  see
598 		 *   icmp6_mtudisc_update().
599 		 */
600 		if ((PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) &&
601 		    IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
602 		    in6p->in6p_route.ro_rt &&
603 		    !(in6p->in6p_route.ro_rt->rt_flags & RTF_HOST)) {
604 			struct sockaddr_in6 *dst6;
605 
606 			dst6 = (struct sockaddr_in6 *)&in6p->in6p_route.ro_dst;
607 			if (IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr,
608 			    &sa6_dst->sin6_addr))
609 				goto do_notify;
610 		}
611 
612 		/*
613 		 * Detect if we should notify the error. If no source and
614 		 * destination ports are specified, but non-zero flowinfo and
615 		 * local address match, notify the error. This is the case
616 		 * when the error is delivered with an encrypted buffer
617 		 * by ESP. Otherwise, just compare addresses and ports
618 		 * as usual.
619 		 */
620 		if (lport == 0 && fport == 0 && flowinfo &&
621 		    in6p->in6p_socket != NULL &&
622 		    flowinfo == (in6p->in6p_flowinfo & IPV6_FLOWLABEL_MASK) &&
623 		    IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &sa6_src.sin6_addr))
624 			goto do_notify;
625 		else if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
626 					     &sa6_dst->sin6_addr) ||
627 		    in6p->in6p_socket == 0 ||
628 		    (lport && in6p->in6p_lport != lport) ||
629 		    (!IN6_IS_ADDR_UNSPECIFIED(&sa6_src.sin6_addr) &&
630 		     !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
631 					 &sa6_src.sin6_addr)) ||
632 		    (fport && in6p->in6p_fport != fport))
633 			continue;
634 
635 	  do_notify:
636 		if (notify)
637 			(*notify)(in6p, errno);
638 		nmatch++;
639 	}
640 	return nmatch;
641 }
642 
643 void
644 in6_pcbpurgeif0(head, ifp)
645 	struct in6pcb *head;
646 	struct ifnet *ifp;
647 {
648 	struct in6pcb *in6p, *nin6p;
649 	struct ip6_moptions *im6o;
650 	struct in6_multi_mship *imm, *nimm;
651 
652 	for (in6p = head->in6p_next; in6p != head; in6p = nin6p) {
653 		nin6p = in6p->in6p_next;
654 		im6o = in6p->in6p_moptions;
655 		if (im6o) {
656 			/*
657 			 * Unselect the outgoing interface if it is being
658 			 * detached.
659 			 */
660 			if (im6o->im6o_multicast_ifp == ifp)
661 				im6o->im6o_multicast_ifp = NULL;
662 
663 			/*
664 			 * Drop multicast group membership if we joined
665 			 * through the interface being detached.
666 			 * XXX controversial - is it really legal for kernel
667 			 * to force this?
668 			 */
669 			for (imm = im6o->im6o_memberships.lh_first;
670 			     imm != NULL; imm = nimm) {
671 				nimm = imm->i6mm_chain.le_next;
672 				if (imm->i6mm_maddr->in6m_ifp == ifp) {
673 					LIST_REMOVE(imm, i6mm_chain);
674 					in6_leavegroup(imm);
675 				}
676 			}
677 		}
678 	}
679 }
680 
681 void
682 in6_pcbpurgeif(head, ifp)
683 	struct in6pcb *head;
684 	struct ifnet *ifp;
685 {
686 	struct in6pcb *in6p, *nin6p;
687 
688 	for (in6p = head->in6p_next; in6p != head; in6p = nin6p) {
689 		nin6p = in6p->in6p_next;
690 		if (in6p->in6p_route.ro_rt != NULL &&
691 		    in6p->in6p_route.ro_rt->rt_ifp == ifp)
692 			in6_rtchange(in6p, 0);
693 	}
694 }
695 
696 /*
697  * Check for alternatives when higher level complains
698  * about service problems.  For now, invalidate cached
699  * routing information.  If the route was created dynamically
700  * (by a redirect), time to try a default gateway again.
701  */
702 void
703 in6_losing(in6p)
704 	struct in6pcb *in6p;
705 {
706 	struct rtentry *rt;
707 	struct rt_addrinfo info;
708 
709 	if ((rt = in6p->in6p_route.ro_rt) != NULL) {
710 		in6p->in6p_route.ro_rt = 0;
711 		bzero((caddr_t)&info, sizeof(info));
712 		info.rti_info[RTAX_DST] =
713 			(struct sockaddr *)&in6p->in6p_route.ro_dst;
714 		info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
715 		info.rti_info[RTAX_NETMASK] = rt_mask(rt);
716 		rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
717 		if (rt->rt_flags & RTF_DYNAMIC) {
718 			(void)rtrequest(RTM_DELETE, rt_key(rt),
719 					rt->rt_gateway, rt_mask(rt), rt->rt_flags,
720 					(struct rtentry **)0);
721 		} else {
722 			/*
723 			 * A new route can be allocated
724 			 * the next time output is attempted.
725 			 */
726 			rtfree(rt);
727 		}
728 	}
729 }
730 
731 /*
732  * After a routing change, flush old routing
733  * and allocate a (hopefully) better one.
734  */
735 void
736 in6_rtchange(in6p, errno)
737 	struct in6pcb *in6p;
738 	int errno;
739 {
740 	if (in6p->in6p_route.ro_rt) {
741 		rtfree(in6p->in6p_route.ro_rt);
742 		in6p->in6p_route.ro_rt = 0;
743 		/*
744 		 * A new route can be allocated the next time
745 		 * output is attempted.
746 		 */
747 	}
748 }
749 
750 struct in6pcb *
751 in6_pcblookup(head, faddr6, fport_arg, laddr6, lport_arg, flags)
752 	struct in6pcb *head;
753 	struct in6_addr *faddr6, *laddr6;
754 	u_int fport_arg, lport_arg;
755 	int flags;
756 {
757 	struct in6pcb *in6p, *match = 0;
758 	int matchwild = 3, wildcard;
759 	u_int16_t fport = fport_arg, lport = lport_arg;
760 
761 	for (in6p = head->in6p_next; in6p != head; in6p = in6p->in6p_next) {
762 		if (in6p->in6p_lport != lport)
763 			continue;
764 		wildcard = 0;
765 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
766 			if (IN6_IS_ADDR_UNSPECIFIED(laddr6))
767 				wildcard++;
768 			else if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, laddr6))
769 				continue;
770 		}
771 		else if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)
772 			&& in6p->in6p_laddr.s6_addr32[3] == 0) {
773 			if (!IN6_IS_ADDR_V4MAPPED(laddr6))
774 				continue;
775 			if (laddr6->s6_addr32[3] == 0)
776 				;
777 			else
778 				wildcard++;
779 		}
780 		else {
781 			if (IN6_IS_ADDR_V4MAPPED(laddr6)) {
782 				if (in6p->in6p_flags & IN6P_IPV6_V6ONLY)
783 					continue;
784 				else
785 					wildcard++;
786 			} else if (!IN6_IS_ADDR_UNSPECIFIED(laddr6))
787 				wildcard++;
788 		}
789 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
790 			if (IN6_IS_ADDR_UNSPECIFIED(faddr6))
791 				wildcard++;
792 			else if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, faddr6)
793 			      || in6p->in6p_fport != fport)
794 				continue;
795 		}
796 		else if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)
797 			&& in6p->in6p_faddr.s6_addr32[3] == 0) {
798 			if (!IN6_IS_ADDR_V4MAPPED(faddr6))
799 				continue;
800 			if (faddr6->s6_addr32[3] == 0)
801 				;
802 			else
803 				wildcard++;
804 		}
805 		else {
806 			if (IN6_IS_ADDR_V4MAPPED(faddr6)) {
807 				if (in6p->in6p_flags & IN6P_IPV6_V6ONLY)
808 					continue;
809 				else
810 					wildcard++;
811 			} else if (!IN6_IS_ADDR_UNSPECIFIED(faddr6))
812 				wildcard++;
813 		}
814 
815 		if (wildcard && (flags & IN6PLOOKUP_WILDCARD) == 0)
816 			continue;
817 		if (wildcard < matchwild) {
818 			match = in6p;
819 			matchwild = wildcard;
820 			if (matchwild == 0)
821 				break;
822 		}
823 	}
824 	return(match);
825 }
826 
827 struct rtentry *
828 in6_pcbrtentry(in6p)
829 	struct in6pcb *in6p;
830 {
831 	struct route_in6 *ro;
832 	struct sockaddr_in6 *dst6;
833 
834 	ro = &in6p->in6p_route;
835 	dst6 = (struct sockaddr_in6 *)&ro->ro_dst;
836 
837 	if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
838 	    !IN6_ARE_ADDR_EQUAL(&dst6->sin6_addr, &in6p->in6p_faddr))) {
839 		RTFREE(ro->ro_rt);
840 		ro->ro_rt = (struct rtentry *)NULL;
841 	}
842 	if (ro->ro_rt == (struct rtentry *)NULL &&
843 	    !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
844 		bzero(dst6, sizeof(*dst6));
845 		dst6->sin6_family = AF_INET6;
846 		dst6->sin6_len = sizeof(struct sockaddr_in6);
847 		dst6->sin6_addr = in6p->in6p_faddr;
848 		rtalloc((struct route *)ro);
849 	}
850 	return (ro->ro_rt);
851 }
852 
853 struct in6pcb *
854 in6_pcblookup_connect(head, faddr6, fport_arg, laddr6, lport_arg, faith)
855 	struct in6pcb *head;
856 	struct in6_addr *faddr6, *laddr6;
857 	u_int fport_arg, lport_arg;
858 	int faith;
859 {
860 	struct in6pcb *in6p;
861 	u_int16_t fport = fport_arg, lport = lport_arg;
862 
863 	for (in6p = head->in6p_next; in6p != head; in6p = in6p->in6p_next) {
864 		/* find exact match on both source and dest */
865 		if (in6p->in6p_fport != fport)
866 			continue;
867 		if (in6p->in6p_lport != lport)
868 			continue;
869 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr))
870 			continue;
871 		if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, faddr6))
872 			continue;
873 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr))
874 			continue;
875 		if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, laddr6))
876 			continue;
877 		if ((IN6_IS_ADDR_V4MAPPED(laddr6) ||
878 		     IN6_IS_ADDR_V4MAPPED(faddr6)) &&
879 		    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
880 			continue;
881 		return in6p;
882 	}
883 	return NULL;
884 }
885 
886 struct in6pcb *
887 in6_pcblookup_bind(head, laddr6, lport_arg, faith)
888 	struct in6pcb *head;
889 	struct in6_addr *laddr6;
890 	u_int lport_arg;
891 	int faith;
892 {
893 	struct in6pcb *in6p, *match;
894 	u_int16_t lport = lport_arg;
895 
896 	match = NULL;
897 	for (in6p = head->in6p_next; in6p != head; in6p = in6p->in6p_next) {
898 		/*
899 	 	 * find destination match.  exact match is preferred
900 		 * against wildcard match.
901 		 */
902 		if (faith && (in6p->in6p_flags & IN6P_FAITH) == 0)
903 			continue;
904 		if (in6p->in6p_fport != 0)
905 			continue;
906 		if (in6p->in6p_lport != lport)
907 			continue;
908 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
909 			if (IN6_IS_ADDR_V4MAPPED(laddr6)) {
910 				if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY))
911 					continue;
912 				else
913 					match = in6p;
914 			} else
915 				match = in6p;
916 		}
917 		else if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr) &&
918 			 !(in6p->in6p_flags & IN6P_IPV6_V6ONLY) &&
919 			 in6p->in6p_laddr.s6_addr32[3] == 0) {
920 			if (IN6_IS_ADDR_V4MAPPED(laddr6) &&
921 			    laddr6->s6_addr32[3] != 0)
922 				match = in6p;
923 		}
924 		else if (IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, laddr6))
925 			return in6p;
926 	}
927 	return match;
928 }
929