xref: /freebsd/sys/netinet6/in6_pcb.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*-
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * Copyright (c) 2010-2011 Juniper Networks, Inc.
4  * All rights reserved.
5  *
6  * Portions of this software were developed by Robert N. M. Watson under
7  * contract to Juniper Networks, Inc.
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  *	$KAME: in6_pcb.c,v 1.31 2001/05/21 05:45:10 jinmei Exp $
34  */
35 
36 /*-
37  * Copyright (c) 1982, 1986, 1991, 1993
38  *	The Regents of the University of California.  All rights reserved.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)in_pcb.c	8.2 (Berkeley) 1/4/94
65  */
66 
67 #include <sys/cdefs.h>
68 __FBSDID("$FreeBSD$");
69 
70 #include "opt_inet.h"
71 #include "opt_inet6.h"
72 #include "opt_ipsec.h"
73 
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/malloc.h>
77 #include <sys/mbuf.h>
78 #include <sys/domain.h>
79 #include <sys/protosw.h>
80 #include <sys/socket.h>
81 #include <sys/socketvar.h>
82 #include <sys/sockio.h>
83 #include <sys/errno.h>
84 #include <sys/time.h>
85 #include <sys/priv.h>
86 #include <sys/proc.h>
87 #include <sys/jail.h>
88 
89 #include <vm/uma.h>
90 
91 #include <net/if.h>
92 #include <net/if_types.h>
93 #include <net/route.h>
94 
95 #include <netinet/in.h>
96 #include <netinet/in_var.h>
97 #include <netinet/in_systm.h>
98 #include <netinet/tcp_var.h>
99 #include <netinet/ip6.h>
100 #include <netinet/ip_var.h>
101 
102 #include <netinet6/ip6_var.h>
103 #include <netinet6/nd6.h>
104 #include <netinet/in_pcb.h>
105 #include <netinet6/in6_pcb.h>
106 #include <netinet6/scope6_var.h>
107 
108 struct	in6_addr zeroin6_addr;
109 
110 int
111 in6_pcbbind(register struct inpcb *inp, struct sockaddr *nam,
112     struct ucred *cred)
113 {
114 	struct socket *so = inp->inp_socket;
115 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)NULL;
116 	struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
117 	u_short	lport = 0;
118 	int error, lookupflags = 0;
119 	int reuseport = (so->so_options & SO_REUSEPORT);
120 
121 	INP_WLOCK_ASSERT(inp);
122 	INP_HASH_WLOCK_ASSERT(pcbinfo);
123 
124 	if (TAILQ_EMPTY(&V_in6_ifaddrhead))	/* XXX broken! */
125 		return (EADDRNOTAVAIL);
126 	if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
127 		return (EINVAL);
128 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
129 		lookupflags = INPLOOKUP_WILDCARD;
130 	if (nam == NULL) {
131 		if ((error = prison_local_ip6(cred, &inp->in6p_laddr,
132 		    ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
133 			return (error);
134 	} else {
135 		sin6 = (struct sockaddr_in6 *)nam;
136 		if (nam->sa_len != sizeof(*sin6))
137 			return (EINVAL);
138 		/*
139 		 * family check.
140 		 */
141 		if (nam->sa_family != AF_INET6)
142 			return (EAFNOSUPPORT);
143 
144 		if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
145 			return(error);
146 
147 		if ((error = prison_local_ip6(cred, &sin6->sin6_addr,
148 		    ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
149 			return (error);
150 
151 		lport = sin6->sin6_port;
152 		if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
153 			/*
154 			 * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
155 			 * allow compepte duplication of binding if
156 			 * SO_REUSEPORT is set, or if SO_REUSEADDR is set
157 			 * and a multicast address is bound on both
158 			 * new and duplicated sockets.
159 			 */
160 			if (so->so_options & SO_REUSEADDR)
161 				reuseport = SO_REUSEADDR|SO_REUSEPORT;
162 		} else if (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
163 			struct ifaddr *ifa;
164 
165 			sin6->sin6_port = 0;		/* yech... */
166 			if ((ifa = ifa_ifwithaddr((struct sockaddr *)sin6)) ==
167 			    NULL &&
168 			    (inp->inp_flags & INP_BINDANY) == 0) {
169 				return (EADDRNOTAVAIL);
170 			}
171 
172 			/*
173 			 * XXX: bind to an anycast address might accidentally
174 			 * cause sending a packet with anycast source address.
175 			 * We should allow to bind to a deprecated address, since
176 			 * the application dares to use it.
177 			 */
178 			if (ifa != NULL &&
179 			    ((struct in6_ifaddr *)ifa)->ia6_flags &
180 			    (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY|IN6_IFF_DETACHED)) {
181 				ifa_free(ifa);
182 				return (EADDRNOTAVAIL);
183 			}
184 			if (ifa != NULL)
185 				ifa_free(ifa);
186 		}
187 		if (lport) {
188 			struct inpcb *t;
189 
190 			/* GROSS */
191 			if (ntohs(lport) <= V_ipport_reservedhigh &&
192 			    ntohs(lport) >= V_ipport_reservedlow &&
193 			    priv_check_cred(cred, PRIV_NETINET_RESERVEDPORT,
194 			    0))
195 				return (EACCES);
196 			if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr) &&
197 			    priv_check_cred(inp->inp_cred,
198 			    PRIV_NETINET_REUSEPORT, 0) != 0) {
199 				t = in6_pcblookup_local(pcbinfo,
200 				    &sin6->sin6_addr, lport,
201 				    INPLOOKUP_WILDCARD, cred);
202 				if (t &&
203 				    ((t->inp_flags & INP_TIMEWAIT) == 0) &&
204 				    (so->so_type != SOCK_STREAM ||
205 				     IN6_IS_ADDR_UNSPECIFIED(&t->in6p_faddr)) &&
206 				    (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) ||
207 				     !IN6_IS_ADDR_UNSPECIFIED(&t->in6p_laddr) ||
208 				     (t->inp_socket->so_options & SO_REUSEPORT)
209 				      == 0) && (inp->inp_cred->cr_uid !=
210 				     t->inp_cred->cr_uid))
211 					return (EADDRINUSE);
212 #ifdef INET
213 				if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
214 				    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
215 					struct sockaddr_in sin;
216 
217 					in6_sin6_2_sin(&sin, sin6);
218 					t = in_pcblookup_local(pcbinfo,
219 					    sin.sin_addr, lport,
220 					    INPLOOKUP_WILDCARD, cred);
221 					if (t &&
222 					    ((t->inp_flags &
223 					      INP_TIMEWAIT) == 0) &&
224 					    (so->so_type != SOCK_STREAM ||
225 					     ntohl(t->inp_faddr.s_addr) ==
226 					      INADDR_ANY) &&
227 					    (inp->inp_cred->cr_uid !=
228 					     t->inp_cred->cr_uid))
229 						return (EADDRINUSE);
230 				}
231 #endif
232 			}
233 			t = in6_pcblookup_local(pcbinfo, &sin6->sin6_addr,
234 			    lport, lookupflags, cred);
235 			if (t && (reuseport & ((t->inp_flags & INP_TIMEWAIT) ?
236 			    intotw(t)->tw_so_options :
237 			    t->inp_socket->so_options)) == 0)
238 				return (EADDRINUSE);
239 #ifdef INET
240 			if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
241 			    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
242 				struct sockaddr_in sin;
243 
244 				in6_sin6_2_sin(&sin, sin6);
245 				t = in_pcblookup_local(pcbinfo, sin.sin_addr,
246 				    lport, lookupflags, cred);
247 				if (t && t->inp_flags & INP_TIMEWAIT) {
248 					if ((reuseport &
249 					    intotw(t)->tw_so_options) == 0 &&
250 					    (ntohl(t->inp_laddr.s_addr) !=
251 					     INADDR_ANY || ((inp->inp_vflag &
252 					     INP_IPV6PROTO) ==
253 					     (t->inp_vflag & INP_IPV6PROTO))))
254 						return (EADDRINUSE);
255 				}
256 				else if (t &&
257 				    (reuseport & t->inp_socket->so_options)
258 				    == 0 && (ntohl(t->inp_laddr.s_addr) !=
259 				    INADDR_ANY || INP_SOCKAF(so) ==
260 				     INP_SOCKAF(t->inp_socket)))
261 					return (EADDRINUSE);
262 			}
263 #endif
264 		}
265 		inp->in6p_laddr = sin6->sin6_addr;
266 	}
267 	if (lport == 0) {
268 		if ((error = in6_pcbsetport(&inp->in6p_laddr, inp, cred)) != 0) {
269 			/* Undo an address bind that may have occurred. */
270 			inp->in6p_laddr = in6addr_any;
271 			return (error);
272 		}
273 	} else {
274 		inp->inp_lport = lport;
275 		if (in_pcbinshash(inp) != 0) {
276 			inp->in6p_laddr = in6addr_any;
277 			inp->inp_lport = 0;
278 			return (EAGAIN);
279 		}
280 	}
281 	return (0);
282 }
283 
284 /*
285  *   Transform old in6_pcbconnect() into an inner subroutine for new
286  *   in6_pcbconnect(): Do some validity-checking on the remote
287  *   address (in mbuf 'nam') and then determine local host address
288  *   (i.e., which interface) to use to access that remote host.
289  *
290  *   This preserves definition of in6_pcbconnect(), while supporting a
291  *   slightly different version for T/TCP.  (This is more than
292  *   a bit of a kludge, but cleaning up the internal interfaces would
293  *   have forced minor changes in every protocol).
294  */
295 int
296 in6_pcbladdr(register struct inpcb *inp, struct sockaddr *nam,
297     struct in6_addr *plocal_addr6)
298 {
299 	register struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
300 	int error = 0;
301 	struct ifnet *ifp = NULL;
302 	int scope_ambiguous = 0;
303 	struct in6_addr in6a;
304 
305 	INP_WLOCK_ASSERT(inp);
306 	INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);	/* XXXRW: why? */
307 
308 	if (nam->sa_len != sizeof (*sin6))
309 		return (EINVAL);
310 	if (sin6->sin6_family != AF_INET6)
311 		return (EAFNOSUPPORT);
312 	if (sin6->sin6_port == 0)
313 		return (EADDRNOTAVAIL);
314 
315 	if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
316 		scope_ambiguous = 1;
317 	if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
318 		return(error);
319 
320 	if (!TAILQ_EMPTY(&V_in6_ifaddrhead)) {
321 		/*
322 		 * If the destination address is UNSPECIFIED addr,
323 		 * use the loopback addr, e.g ::1.
324 		 */
325 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
326 			sin6->sin6_addr = in6addr_loopback;
327 	}
328 	if ((error = prison_remote_ip6(inp->inp_cred, &sin6->sin6_addr)) != 0)
329 		return (error);
330 
331 	error = in6_selectsrc(sin6, inp->in6p_outputopts,
332 	    inp, NULL, inp->inp_cred, &ifp, &in6a);
333 	if (error)
334 		return (error);
335 
336 	if (ifp && scope_ambiguous &&
337 	    (error = in6_setscope(&sin6->sin6_addr, ifp, NULL)) != 0) {
338 		return(error);
339 	}
340 
341 	/*
342 	 * Do not update this earlier, in case we return with an error.
343 	 *
344 	 * XXX: this in6_selectsrc result might replace the bound local
345 	 * address with the address specified by setsockopt(IPV6_PKTINFO).
346 	 * Is it the intended behavior?
347 	 */
348 	*plocal_addr6 = in6a;
349 
350 	/*
351 	 * Don't do pcblookup call here; return interface in
352 	 * plocal_addr6
353 	 * and exit to caller, that will do the lookup.
354 	 */
355 
356 	return (0);
357 }
358 
359 /*
360  * Outer subroutine:
361  * Connect from a socket to a specified address.
362  * Both address and port must be specified in argument sin.
363  * If don't have a local address for this socket yet,
364  * then pick one.
365  */
366 int
367 in6_pcbconnect_mbuf(register struct inpcb *inp, struct sockaddr *nam,
368     struct ucred *cred, struct mbuf *m)
369 {
370 	struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
371 	register struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
372 	struct in6_addr addr6;
373 	int error;
374 
375 	INP_WLOCK_ASSERT(inp);
376 	INP_HASH_WLOCK_ASSERT(pcbinfo);
377 
378 	/*
379 	 * Call inner routine, to assign local interface address.
380 	 * in6_pcbladdr() may automatically fill in sin6_scope_id.
381 	 */
382 	if ((error = in6_pcbladdr(inp, nam, &addr6)) != 0)
383 		return (error);
384 
385 	if (in6_pcblookup_hash_locked(pcbinfo, &sin6->sin6_addr,
386 			       sin6->sin6_port,
387 			      IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
388 			      ? &addr6 : &inp->in6p_laddr,
389 			      inp->inp_lport, 0, NULL) != NULL) {
390 		return (EADDRINUSE);
391 	}
392 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
393 		if (inp->inp_lport == 0) {
394 			error = in6_pcbbind(inp, (struct sockaddr *)0, cred);
395 			if (error)
396 				return (error);
397 		}
398 		inp->in6p_laddr = addr6;
399 	}
400 	inp->in6p_faddr = sin6->sin6_addr;
401 	inp->inp_fport = sin6->sin6_port;
402 	/* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
403 	inp->inp_flow &= ~IPV6_FLOWLABEL_MASK;
404 	if (inp->inp_flags & IN6P_AUTOFLOWLABEL)
405 		inp->inp_flow |=
406 		    (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
407 
408 	in_pcbrehash_mbuf(inp, m);
409 
410 	return (0);
411 }
412 
413 int
414 in6_pcbconnect(struct inpcb *inp, struct sockaddr *nam, struct ucred *cred)
415 {
416 
417 	return (in6_pcbconnect_mbuf(inp, nam, cred, NULL));
418 }
419 
420 void
421 in6_pcbdisconnect(struct inpcb *inp)
422 {
423 
424 	INP_WLOCK_ASSERT(inp);
425 	INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
426 
427 	bzero((caddr_t)&inp->in6p_faddr, sizeof(inp->in6p_faddr));
428 	inp->inp_fport = 0;
429 	/* clear flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
430 	inp->inp_flow &= ~IPV6_FLOWLABEL_MASK;
431 	in_pcbrehash(inp);
432 }
433 
434 struct sockaddr *
435 in6_sockaddr(in_port_t port, struct in6_addr *addr_p)
436 {
437 	struct sockaddr_in6 *sin6;
438 
439 	sin6 = malloc(sizeof *sin6, M_SONAME, M_WAITOK);
440 	bzero(sin6, sizeof *sin6);
441 	sin6->sin6_family = AF_INET6;
442 	sin6->sin6_len = sizeof(*sin6);
443 	sin6->sin6_port = port;
444 	sin6->sin6_addr = *addr_p;
445 	(void)sa6_recoverscope(sin6); /* XXX: should catch errors */
446 
447 	return (struct sockaddr *)sin6;
448 }
449 
450 struct sockaddr *
451 in6_v4mapsin6_sockaddr(in_port_t port, struct in_addr *addr_p)
452 {
453 	struct sockaddr_in sin;
454 	struct sockaddr_in6 *sin6_p;
455 
456 	bzero(&sin, sizeof sin);
457 	sin.sin_family = AF_INET;
458 	sin.sin_len = sizeof(sin);
459 	sin.sin_port = port;
460 	sin.sin_addr = *addr_p;
461 
462 	sin6_p = malloc(sizeof *sin6_p, M_SONAME,
463 		M_WAITOK);
464 	in6_sin_2_v4mapsin6(&sin, sin6_p);
465 
466 	return (struct sockaddr *)sin6_p;
467 }
468 
469 int
470 in6_getsockaddr(struct socket *so, struct sockaddr **nam)
471 {
472 	register struct inpcb *inp;
473 	struct in6_addr addr;
474 	in_port_t port;
475 
476 	inp = sotoinpcb(so);
477 	KASSERT(inp != NULL, ("in6_getsockaddr: inp == NULL"));
478 
479 	INP_RLOCK(inp);
480 	port = inp->inp_lport;
481 	addr = inp->in6p_laddr;
482 	INP_RUNLOCK(inp);
483 
484 	*nam = in6_sockaddr(port, &addr);
485 	return 0;
486 }
487 
488 int
489 in6_getpeeraddr(struct socket *so, struct sockaddr **nam)
490 {
491 	struct inpcb *inp;
492 	struct in6_addr addr;
493 	in_port_t port;
494 
495 	inp = sotoinpcb(so);
496 	KASSERT(inp != NULL, ("in6_getpeeraddr: inp == NULL"));
497 
498 	INP_RLOCK(inp);
499 	port = inp->inp_fport;
500 	addr = inp->in6p_faddr;
501 	INP_RUNLOCK(inp);
502 
503 	*nam = in6_sockaddr(port, &addr);
504 	return 0;
505 }
506 
507 int
508 in6_mapped_sockaddr(struct socket *so, struct sockaddr **nam)
509 {
510 	struct	inpcb *inp;
511 	int	error;
512 
513 	inp = sotoinpcb(so);
514 	KASSERT(inp != NULL, ("in6_mapped_sockaddr: inp == NULL"));
515 
516 #ifdef INET
517 	if ((inp->inp_vflag & (INP_IPV4 | INP_IPV6)) == INP_IPV4) {
518 		error = in_getsockaddr(so, nam);
519 		if (error == 0)
520 			in6_sin_2_v4mapsin6_in_sock(nam);
521 	} else
522 #endif
523 	{
524 		/* scope issues will be handled in in6_getsockaddr(). */
525 		error = in6_getsockaddr(so, nam);
526 	}
527 
528 	return error;
529 }
530 
531 int
532 in6_mapped_peeraddr(struct socket *so, struct sockaddr **nam)
533 {
534 	struct	inpcb *inp;
535 	int	error;
536 
537 	inp = sotoinpcb(so);
538 	KASSERT(inp != NULL, ("in6_mapped_peeraddr: inp == NULL"));
539 
540 #ifdef INET
541 	if ((inp->inp_vflag & (INP_IPV4 | INP_IPV6)) == INP_IPV4) {
542 		error = in_getpeeraddr(so, nam);
543 		if (error == 0)
544 			in6_sin_2_v4mapsin6_in_sock(nam);
545 	} else
546 #endif
547 	/* scope issues will be handled in in6_getpeeraddr(). */
548 	error = in6_getpeeraddr(so, nam);
549 
550 	return error;
551 }
552 
553 /*
554  * Pass some notification to all connections of a protocol
555  * associated with address dst.  The local address and/or port numbers
556  * may be specified to limit the search.  The "usual action" will be
557  * taken, depending on the ctlinput cmd.  The caller must filter any
558  * cmds that are uninteresting (e.g., no error in the map).
559  * Call the protocol specific routine (if any) to report
560  * any errors for each matching socket.
561  */
562 void
563 in6_pcbnotify(struct inpcbinfo *pcbinfo, struct sockaddr *dst,
564     u_int fport_arg, const struct sockaddr *src, u_int lport_arg,
565     int cmd, void *cmdarg,
566     struct inpcb *(*notify)(struct inpcb *, int))
567 {
568 	struct inpcb *inp, *inp_temp;
569 	struct sockaddr_in6 sa6_src, *sa6_dst;
570 	u_short	fport = fport_arg, lport = lport_arg;
571 	u_int32_t flowinfo;
572 	int errno;
573 
574 	if ((unsigned)cmd >= PRC_NCMDS || dst->sa_family != AF_INET6)
575 		return;
576 
577 	sa6_dst = (struct sockaddr_in6 *)dst;
578 	if (IN6_IS_ADDR_UNSPECIFIED(&sa6_dst->sin6_addr))
579 		return;
580 
581 	/*
582 	 * note that src can be NULL when we get notify by local fragmentation.
583 	 */
584 	sa6_src = (src == NULL) ? sa6_any : *(const struct sockaddr_in6 *)src;
585 	flowinfo = sa6_src.sin6_flowinfo;
586 
587 	/*
588 	 * Redirects go to all references to the destination,
589 	 * and use in6_rtchange to invalidate the route cache.
590 	 * Dead host indications: also use in6_rtchange to invalidate
591 	 * the cache, and deliver the error to all the sockets.
592 	 * Otherwise, if we have knowledge of the local port and address,
593 	 * deliver only to that socket.
594 	 */
595 	if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
596 		fport = 0;
597 		lport = 0;
598 		bzero((caddr_t)&sa6_src.sin6_addr, sizeof(sa6_src.sin6_addr));
599 
600 		if (cmd != PRC_HOSTDEAD)
601 			notify = in6_rtchange;
602 	}
603 	errno = inet6ctlerrmap[cmd];
604 	INP_INFO_WLOCK(pcbinfo);
605 	LIST_FOREACH_SAFE(inp, pcbinfo->ipi_listhead, inp_list, inp_temp) {
606 		INP_WLOCK(inp);
607 		if ((inp->inp_vflag & INP_IPV6) == 0) {
608 			INP_WUNLOCK(inp);
609 			continue;
610 		}
611 
612 		/*
613 		 * If the error designates a new path MTU for a destination
614 		 * and the application (associated with this socket) wanted to
615 		 * know the value, notify. Note that we notify for all
616 		 * disconnected sockets if the corresponding application
617 		 * wanted. This is because some UDP applications keep sending
618 		 * sockets disconnected.
619 		 * XXX: should we avoid to notify the value to TCP sockets?
620 		 */
621 		if (cmd == PRC_MSGSIZE && (inp->inp_flags & IN6P_MTU) != 0 &&
622 		    (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) ||
623 		     IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &sa6_dst->sin6_addr))) {
624 			ip6_notify_pmtu(inp, (struct sockaddr_in6 *)dst,
625 					(u_int32_t *)cmdarg);
626 		}
627 
628 		/*
629 		 * Detect if we should notify the error. If no source and
630 		 * destination ports are specifed, but non-zero flowinfo and
631 		 * local address match, notify the error. This is the case
632 		 * when the error is delivered with an encrypted buffer
633 		 * by ESP. Otherwise, just compare addresses and ports
634 		 * as usual.
635 		 */
636 		if (lport == 0 && fport == 0 && flowinfo &&
637 		    inp->inp_socket != NULL &&
638 		    flowinfo == (inp->inp_flow & IPV6_FLOWLABEL_MASK) &&
639 		    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &sa6_src.sin6_addr))
640 			goto do_notify;
641 		else if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
642 					     &sa6_dst->sin6_addr) ||
643 			 inp->inp_socket == 0 ||
644 			 (lport && inp->inp_lport != lport) ||
645 			 (!IN6_IS_ADDR_UNSPECIFIED(&sa6_src.sin6_addr) &&
646 			  !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
647 					      &sa6_src.sin6_addr)) ||
648 			 (fport && inp->inp_fport != fport)) {
649 			INP_WUNLOCK(inp);
650 			continue;
651 		}
652 
653 	  do_notify:
654 		if (notify) {
655 			if ((*notify)(inp, errno))
656 				INP_WUNLOCK(inp);
657 		} else
658 			INP_WUNLOCK(inp);
659 	}
660 	INP_INFO_WUNLOCK(pcbinfo);
661 }
662 
663 /*
664  * Lookup a PCB based on the local address and port.  Caller must hold the
665  * hash lock.  No inpcb locks or references are acquired.
666  */
667 struct inpcb *
668 in6_pcblookup_local(struct inpcbinfo *pcbinfo, struct in6_addr *laddr,
669     u_short lport, int lookupflags, struct ucred *cred)
670 {
671 	register struct inpcb *inp;
672 	int matchwild = 3, wildcard;
673 
674 	KASSERT((lookupflags & ~(INPLOOKUP_WILDCARD)) == 0,
675 	    ("%s: invalid lookup flags %d", __func__, lookupflags));
676 
677 	INP_HASH_WLOCK_ASSERT(pcbinfo);
678 
679 	if ((lookupflags & INPLOOKUP_WILDCARD) == 0) {
680 		struct inpcbhead *head;
681 		/*
682 		 * Look for an unconnected (wildcard foreign addr) PCB that
683 		 * matches the local address and port we're looking for.
684 		 */
685 		head = &pcbinfo->ipi_hashbase[INP_PCBHASH(INADDR_ANY, lport,
686 		    0, pcbinfo->ipi_hashmask)];
687 		LIST_FOREACH(inp, head, inp_hash) {
688 			/* XXX inp locking */
689 			if ((inp->inp_vflag & INP_IPV6) == 0)
690 				continue;
691 			if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
692 			    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
693 			    inp->inp_lport == lport) {
694 				/* Found. */
695 				if (cred == NULL ||
696 				    prison_equal_ip6(cred->cr_prison,
697 					inp->inp_cred->cr_prison))
698 					return (inp);
699 			}
700 		}
701 		/*
702 		 * Not found.
703 		 */
704 		return (NULL);
705 	} else {
706 		struct inpcbporthead *porthash;
707 		struct inpcbport *phd;
708 		struct inpcb *match = NULL;
709 		/*
710 		 * Best fit PCB lookup.
711 		 *
712 		 * First see if this local port is in use by looking on the
713 		 * port hash list.
714 		 */
715 		porthash = &pcbinfo->ipi_porthashbase[INP_PCBPORTHASH(lport,
716 		    pcbinfo->ipi_porthashmask)];
717 		LIST_FOREACH(phd, porthash, phd_hash) {
718 			if (phd->phd_port == lport)
719 				break;
720 		}
721 		if (phd != NULL) {
722 			/*
723 			 * Port is in use by one or more PCBs. Look for best
724 			 * fit.
725 			 */
726 			LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
727 				wildcard = 0;
728 				if (cred != NULL &&
729 				    !prison_equal_ip6(cred->cr_prison,
730 					inp->inp_cred->cr_prison))
731 					continue;
732 				/* XXX inp locking */
733 				if ((inp->inp_vflag & INP_IPV6) == 0)
734 					continue;
735 				if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
736 					wildcard++;
737 				if (!IN6_IS_ADDR_UNSPECIFIED(
738 					&inp->in6p_laddr)) {
739 					if (IN6_IS_ADDR_UNSPECIFIED(laddr))
740 						wildcard++;
741 					else if (!IN6_ARE_ADDR_EQUAL(
742 					    &inp->in6p_laddr, laddr))
743 						continue;
744 				} else {
745 					if (!IN6_IS_ADDR_UNSPECIFIED(laddr))
746 						wildcard++;
747 				}
748 				if (wildcard < matchwild) {
749 					match = inp;
750 					matchwild = wildcard;
751 					if (matchwild == 0)
752 						break;
753 				}
754 			}
755 		}
756 		return (match);
757 	}
758 }
759 
760 void
761 in6_pcbpurgeif0(struct inpcbinfo *pcbinfo, struct ifnet *ifp)
762 {
763 	struct inpcb *in6p;
764 	struct ip6_moptions *im6o;
765 	int i, gap;
766 
767 	INP_INFO_RLOCK(pcbinfo);
768 	LIST_FOREACH(in6p, pcbinfo->ipi_listhead, inp_list) {
769 		INP_WLOCK(in6p);
770 		im6o = in6p->in6p_moptions;
771 		if ((in6p->inp_vflag & INP_IPV6) && im6o != NULL) {
772 			/*
773 			 * Unselect the outgoing ifp for multicast if it
774 			 * is being detached.
775 			 */
776 			if (im6o->im6o_multicast_ifp == ifp)
777 				im6o->im6o_multicast_ifp = NULL;
778 			/*
779 			 * Drop multicast group membership if we joined
780 			 * through the interface being detached.
781 			 */
782 			gap = 0;
783 			for (i = 0; i < im6o->im6o_num_memberships; i++) {
784 				if (im6o->im6o_membership[i]->in6m_ifp ==
785 				    ifp) {
786 					in6_mc_leave(im6o->im6o_membership[i],
787 					    NULL);
788 					gap++;
789 				} else if (gap != 0) {
790 					im6o->im6o_membership[i - gap] =
791 					    im6o->im6o_membership[i];
792 				}
793 			}
794 			im6o->im6o_num_memberships -= gap;
795 		}
796 		INP_WUNLOCK(in6p);
797 	}
798 	INP_INFO_RUNLOCK(pcbinfo);
799 }
800 
801 /*
802  * Check for alternatives when higher level complains
803  * about service problems.  For now, invalidate cached
804  * routing information.  If the route was created dynamically
805  * (by a redirect), time to try a default gateway again.
806  */
807 void
808 in6_losing(struct inpcb *in6p)
809 {
810 
811 	/*
812 	 * We don't store route pointers in the routing table anymore
813 	 */
814 	return;
815 }
816 
817 /*
818  * After a routing change, flush old routing
819  * and allocate a (hopefully) better one.
820  */
821 struct inpcb *
822 in6_rtchange(struct inpcb *inp, int errno)
823 {
824 	/*
825 	 * We don't store route pointers in the routing table anymore
826 	 */
827 	return inp;
828 }
829 
830 /*
831  * Lookup PCB in hash list.
832  */
833 struct inpcb *
834 in6_pcblookup_hash_locked(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
835     u_int fport_arg, struct in6_addr *laddr, u_int lport_arg,
836     int lookupflags, struct ifnet *ifp)
837 {
838 	struct inpcbhead *head;
839 	struct inpcb *inp, *tmpinp;
840 	u_short fport = fport_arg, lport = lport_arg;
841 	int faith;
842 
843 	KASSERT((lookupflags & ~(INPLOOKUP_WILDCARD)) == 0,
844 	    ("%s: invalid lookup flags %d", __func__, lookupflags));
845 
846 	INP_HASH_LOCK_ASSERT(pcbinfo);
847 
848 	if (faithprefix_p != NULL)
849 		faith = (*faithprefix_p)(laddr);
850 	else
851 		faith = 0;
852 
853 	/*
854 	 * First look for an exact match.
855 	 */
856 	tmpinp = NULL;
857 	head = &pcbinfo->ipi_hashbase[
858 	    INP_PCBHASH(faddr->s6_addr32[3] /* XXX */, lport, fport,
859 	    pcbinfo->ipi_hashmask)];
860 	LIST_FOREACH(inp, head, inp_hash) {
861 		/* XXX inp locking */
862 		if ((inp->inp_vflag & INP_IPV6) == 0)
863 			continue;
864 		if (IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, faddr) &&
865 		    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
866 		    inp->inp_fport == fport &&
867 		    inp->inp_lport == lport) {
868 			/*
869 			 * XXX We should be able to directly return
870 			 * the inp here, without any checks.
871 			 * Well unless both bound with SO_REUSEPORT?
872 			 */
873 			if (prison_flag(inp->inp_cred, PR_IP6))
874 				return (inp);
875 			if (tmpinp == NULL)
876 				tmpinp = inp;
877 		}
878 	}
879 	if (tmpinp != NULL)
880 		return (tmpinp);
881 
882 	/*
883 	 * Then look for a wildcard match, if requested.
884 	 */
885 	if ((lookupflags & INPLOOKUP_WILDCARD) != 0) {
886 		struct inpcb *local_wild = NULL, *local_exact = NULL;
887 		struct inpcb *jail_wild = NULL;
888 		int injail;
889 
890 		/*
891 		 * Order of socket selection - we always prefer jails.
892 		 *      1. jailed, non-wild.
893 		 *      2. jailed, wild.
894 		 *      3. non-jailed, non-wild.
895 		 *      4. non-jailed, wild.
896 		 */
897 		head = &pcbinfo->ipi_hashbase[INP_PCBHASH(INADDR_ANY, lport,
898 		    0, pcbinfo->ipi_hashmask)];
899 		LIST_FOREACH(inp, head, inp_hash) {
900 			/* XXX inp locking */
901 			if ((inp->inp_vflag & INP_IPV6) == 0)
902 				continue;
903 
904 			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) ||
905 			    inp->inp_lport != lport) {
906 				continue;
907 			}
908 
909 			/* XXX inp locking */
910 			if (faith && (inp->inp_flags & INP_FAITH) == 0)
911 				continue;
912 
913 			injail = prison_flag(inp->inp_cred, PR_IP6);
914 			if (injail) {
915 				if (prison_check_ip6(inp->inp_cred,
916 				    laddr) != 0)
917 					continue;
918 			} else {
919 				if (local_exact != NULL)
920 					continue;
921 			}
922 
923 			if (IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr)) {
924 				if (injail)
925 					return (inp);
926 				else
927 					local_exact = inp;
928 			} else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
929 				if (injail)
930 					jail_wild = inp;
931 				else
932 					local_wild = inp;
933 			}
934 		} /* LIST_FOREACH */
935 
936 		if (jail_wild != NULL)
937 			return (jail_wild);
938 		if (local_exact != NULL)
939 			return (local_exact);
940 		if (local_wild != NULL)
941 			return (local_wild);
942 	} /* if ((lookupflags & INPLOOKUP_WILDCARD) != 0) */
943 
944 	/*
945 	 * Not found.
946 	 */
947 	return (NULL);
948 }
949 
950 /*
951  * Lookup PCB in hash list, using pcbinfo tables.  This variation locks the
952  * hash list lock, and will return the inpcb locked (i.e., requires
953  * INPLOOKUP_LOCKPCB).
954  */
955 static struct inpcb *
956 in6_pcblookup_hash(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
957     u_int fport, struct in6_addr *laddr, u_int lport, int lookupflags,
958     struct ifnet *ifp)
959 {
960 	struct inpcb *inp;
961 
962 	INP_HASH_RLOCK(pcbinfo);
963 	inp = in6_pcblookup_hash_locked(pcbinfo, faddr, fport, laddr, lport,
964 	    (lookupflags & ~(INPLOOKUP_RLOCKPCB | INPLOOKUP_WLOCKPCB)), ifp);
965 	if (inp != NULL) {
966 		in_pcbref(inp);
967 		INP_HASH_RUNLOCK(pcbinfo);
968 		if (lookupflags & INPLOOKUP_WLOCKPCB) {
969 			INP_WLOCK(inp);
970 			if (in_pcbrele_wlocked(inp))
971 				return (NULL);
972 		} else if (lookupflags & INPLOOKUP_RLOCKPCB) {
973 			INP_RLOCK(inp);
974 			if (in_pcbrele_rlocked(inp))
975 				return (NULL);
976 		} else
977 			panic("%s: locking bug", __func__);
978 	} else
979 		INP_HASH_RUNLOCK(pcbinfo);
980 	return (inp);
981 }
982 
983 /*
984  * Public inpcb lookup routines, accepting a 4-tuple, and optionally, an mbuf
985  * from which a pre-calculated hash value may be extracted.
986  */
987 struct inpcb *
988 in6_pcblookup(struct inpcbinfo *pcbinfo, struct in6_addr *faddr, u_int fport,
989     struct in6_addr *laddr, u_int lport, int lookupflags, struct ifnet *ifp)
990 {
991 	KASSERT((lookupflags & ~INPLOOKUP_MASK) == 0,
992 	    ("%s: invalid lookup flags %d", __func__, lookupflags));
993 	KASSERT((lookupflags & (INPLOOKUP_RLOCKPCB | INPLOOKUP_WLOCKPCB)) != 0,
994 	    ("%s: LOCKPCB not set", __func__));
995 
996 	return (in6_pcblookup_hash(pcbinfo, faddr, fport, laddr, lport,
997 	    lookupflags, ifp));
998 }
999 
1000 struct inpcb *
1001 in6_pcblookup_mbuf(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
1002     u_int fport, struct in6_addr *laddr, u_int lport, int lookupflags,
1003     struct ifnet *ifp, struct mbuf *m)
1004 {
1005 	KASSERT((lookupflags & ~INPLOOKUP_MASK) == 0,
1006 	    ("%s: invalid lookup flags %d", __func__, lookupflags));
1007 	KASSERT((lookupflags & (INPLOOKUP_RLOCKPCB | INPLOOKUP_WLOCKPCB)) != 0,
1008 	    ("%s: LOCKPCB not set", __func__));
1009 
1010 	return (in6_pcblookup_hash(pcbinfo, faddr, fport, laddr, lport,
1011 	    lookupflags, ifp));
1012 }
1013 
1014 void
1015 init_sin6(struct sockaddr_in6 *sin6, struct mbuf *m)
1016 {
1017 	struct ip6_hdr *ip;
1018 
1019 	ip = mtod(m, struct ip6_hdr *);
1020 	bzero(sin6, sizeof(*sin6));
1021 	sin6->sin6_len = sizeof(*sin6);
1022 	sin6->sin6_family = AF_INET6;
1023 	sin6->sin6_addr = ip->ip6_src;
1024 
1025 	(void)sa6_recoverscope(sin6); /* XXX: should catch errors... */
1026 
1027 	return;
1028 }
1029