udp6_usrreq.c revision 1.43
1/*	$NetBSD: udp6_usrreq.c,v 1.43 2001/05/27 17:36:07 itojun Exp $	*/
2/*	$KAME: udp6_usrreq.c,v 1.86 2001/05/27 17:33:00 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, 1989, 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 *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
66 */
67
68#include "opt_ipsec.h"
69
70#include <sys/param.h>
71#include <sys/malloc.h>
72#include <sys/mbuf.h>
73#include <sys/protosw.h>
74#include <sys/socket.h>
75#include <sys/socketvar.h>
76#include <sys/errno.h>
77#include <sys/stat.h>
78#include <sys/systm.h>
79#include <sys/proc.h>
80#include <sys/syslog.h>
81
82#include <net/if.h>
83#include <net/route.h>
84#include <net/if_types.h>
85
86#include <netinet/in.h>
87#include <netinet/in_var.h>
88#include <netinet/in_systm.h>
89#include <netinet/ip.h>
90#include <netinet/ip_var.h>
91#include <netinet/in_pcb.h>
92#include <netinet/udp.h>
93#include <netinet/udp_var.h>
94#include <netinet/ip6.h>
95#include <netinet6/ip6_var.h>
96#include <netinet6/in6_pcb.h>
97#include <netinet/icmp6.h>
98#include <netinet6/udp6_var.h>
99#include <netinet6/ip6protosw.h>
100
101#ifdef IPSEC
102#include <netinet6/ipsec.h>
103#endif /*IPSEC*/
104
105#include "faith.h"
106#if defined(NFAITH) && NFAITH > 0
107#include <net/if_faith.h>
108#endif
109
110/*
111 * UDP protocol inplementation.
112 * Per RFC 768, August, 1980.
113 */
114
115struct	in6pcb *udp6_last_in6pcb = &udb6;
116
117#ifdef UDP6
118static	int in6_mcmatch __P((struct in6pcb *, struct in6_addr *, struct ifnet *));
119#endif
120static	void udp6_detach __P((struct in6pcb *));
121static	void udp6_notify __P((struct in6pcb *, int));
122
123void
124udp6_init()
125{
126	udb6.in6p_next = udb6.in6p_prev = &udb6;
127}
128
129#ifdef UDP6
130static int
131in6_mcmatch(in6p, ia6, ifp)
132	struct in6pcb *in6p;
133	struct in6_addr *ia6;
134	struct ifnet *ifp;
135{
136	struct ip6_moptions *im6o = in6p->in6p_moptions;
137	struct in6_multi_mship *imm;
138
139	if (im6o == NULL)
140		return 0;
141
142	for (imm = im6o->im6o_memberships.lh_first; imm != NULL;
143	     imm = imm->i6mm_chain.le_next) {
144		if ((ifp == NULL ||
145		     imm->i6mm_maddr->in6m_ifp == ifp) &&
146		    IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
147				       ia6))
148			return 1;
149	}
150	return 0;
151}
152
153int
154udp6_input(mp, offp, proto)
155	struct mbuf **mp;
156	int *offp, proto;
157{
158	struct mbuf *m = *mp;
159	struct ip6_hdr *ip6;
160	struct udphdr *uh;
161	struct in6pcb *in6p;
162	struct	mbuf *opts = 0;
163	int off = *offp;
164	u_int32_t plen, ulen;
165	struct sockaddr_in6 udp_in6;
166
167	ip6 = mtod(m, struct ip6_hdr *);
168
169#if defined(NFAITH) && 0 < NFAITH
170	if (faithprefix(&ip6->ip6_dst)) {
171		/* send icmp6 host unreach? */
172		m_freem(m);
173		return IPPROTO_DONE;
174	}
175#endif
176
177	udp6stat.udp6s_ipackets++;
178
179	/* check for jumbogram is done in ip6_input.  we can trust pkthdr.len */
180	plen = m->m_pkthdr.len - off;
181#ifndef PULLDOWN_TEST
182	IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
183	uh = (struct udphdr *)((caddr_t)ip6 + off);
184#else
185	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
186	if (uh == NULL) {
187		udp6stat.udp6s_hdrops++;
188		return IPPROTO_DONE;
189	}
190#endif
191	ulen = ntohs((u_short)uh->uh_ulen);
192	/*
193	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
194	 * iff payload length > 0xffff.
195	 */
196	if (ulen == 0 && plen > 0xffff)
197		ulen = plen;
198
199	if (plen != ulen) {
200		udp6stat.udp6s_badlen++;
201		goto bad;
202	}
203
204	/* destination port of 0 is illegal, based on RFC768. */
205	if (uh->uh_dport == 0)
206		goto bad;
207
208	/* Be proactive about malicious use of IPv4 mapped address */
209	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
210	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
211		/* XXX stat */
212		goto bad;
213	}
214
215	/*
216	 * Checksum extended UDP header and data.
217	 */
218	if (uh->uh_sum == 0)
219		udp6stat.udp6s_nosum++;
220	else if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
221		udp6stat.udp6s_badsum++;
222		goto bad;
223	}
224
225	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
226		struct	in6pcb *last;
227
228		/*
229		 * Deliver a multicast datagram to all sockets
230		 * for which the local and remote addresses and ports match
231		 * those of the incoming datagram.  This allows more than
232		 * one process to receive multicasts on the same port.
233		 * (This really ought to be done for unicast datagrams as
234		 * well, but that would cause problems with existing
235		 * applications that open both address-specific sockets and
236		 * a wildcard socket listening to the same port -- they would
237		 * end up receiving duplicates of every unicast datagram.
238		 * Those applications open the multiple sockets to overcome an
239		 * inadequacy of the UDP socket interface, but for backwards
240		 * compatibility we avoid the problem here rather than
241		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
242		 */
243
244		/*
245		 * In a case that laddr should be set to the link-local
246		 * address (this happens in RIPng), the multicast address
247		 * specified in the received packet does not match with
248		 * laddr. To cure this situation, the matching is relaxed
249		 * if the receiving interface is the same as one specified
250		 * in the socket and if the destination multicast address
251		 * matches one of the multicast groups specified in the socket.
252		 */
253
254		/*
255		 * Construct sockaddr format source address.
256		 */
257		bzero(&udp_in6, sizeof(udp_in6));
258		udp_in6.sin6_len = sizeof(struct sockaddr_in6);
259		udp_in6.sin6_family = AF_INET6;
260		udp_in6.sin6_port = uh->uh_sport;
261#if 0 /*XXX inbound flowinfo */
262		udp_in6.sin6_flowinfo = ip6->ip6_flow & IPV6_FLOWINFO_MASK;
263#endif
264		/* KAME hack: recover scopeid */
265		(void)in6_recoverscope(&udp_in6, &ip6->ip6_src,
266		    m->m_pkthdr.rcvif);
267
268		/*
269		 * KAME note: usually we drop udphdr from mbuf here.
270		 * We need udphdr for IPsec processing so we do that later.
271		 */
272
273		/*
274		 * Locate pcb(s) for datagram.
275		 * (Algorithm copied from raw_intr().)
276		 */
277		last = NULL;
278		for (in6p = udb6.in6p_next;
279		     in6p != &udb6;
280		     in6p = in6p->in6p_next) {
281			if (in6p->in6p_lport != uh->uh_dport)
282				continue;
283			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
284				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
285							&ip6->ip6_dst) &&
286				    !in6_mcmatch(in6p, &ip6->ip6_dst,
287						 m->m_pkthdr.rcvif))
288					continue;
289			}
290			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
291				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
292							&ip6->ip6_src) ||
293				   in6p->in6p_fport != uh->uh_sport)
294					continue;
295			}
296
297			if (last != NULL) {
298				struct	mbuf *n;
299
300#ifdef IPSEC
301				/*
302				 * Check AH/ESP integrity.
303				 */
304				if (ipsec6_in_reject(m, last)) {
305					ipsec6stat.in_polvio++;
306					/* do not inject data into pcb */
307				} else
308#endif /*IPSEC*/
309				if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
310					/*
311					 * KAME NOTE: do not
312					 * m_copy(m, offset, ...) above.
313					 * sbappendaddr() expects M_PKTHDR,
314					 * and m_copy() will copy M_PKTHDR
315					 * only if offset is 0.
316					 */
317					if (last->in6p_flags & IN6P_CONTROLOPTS
318					 || last->in6p_socket->so_options & SO_TIMESTAMP) {
319						ip6_savecontrol(last, &opts,
320								ip6, n);
321					}
322
323					m_adj(n, off + sizeof(struct udphdr));
324					if (sbappendaddr(&last->in6p_socket->so_rcv,
325							(struct sockaddr *)&udp_in6,
326							n, opts) == 0) {
327						m_freem(n);
328						if (opts)
329							m_freem(opts);
330						udp6stat.udp6s_fullsock++;
331					} else
332						sorwakeup(last->in6p_socket);
333					opts = 0;
334				}
335			}
336			last = in6p;
337			/*
338			 * Don't look for additional matches if this one does
339			 * not have either the SO_REUSEPORT or SO_REUSEADDR
340			 * socket options set.  This heuristic avoids searching
341			 * through all pcbs in the common case of a non-shared
342			 * port.  It assumes that an application will never
343			 * clear these options after setting them.
344			 */
345			if ((last->in6p_socket->so_options &
346			     (SO_REUSEPORT|SO_REUSEADDR)) == 0)
347				break;
348		}
349
350		if (last == NULL) {
351			/*
352			 * No matching pcb found; discard datagram.
353			 * (No need to send an ICMP Port Unreachable
354			 * for a broadcast or multicast datgram.)
355			 */
356			udp6stat.udp6s_noport++;
357			udp6stat.udp6s_noportmcast++;
358			goto bad;
359		}
360#ifdef IPSEC
361		/*
362		 * Check AH/ESP integrity.
363		 */
364		if (last != NULL && ipsec6_in_reject(m, last)) {
365			ipsec6stat.in_polvio++;
366			goto bad;
367		}
368#endif /*IPSEC*/
369		if (last->in6p_flags & IN6P_CONTROLOPTS
370		 || last->in6p_socket->so_options & SO_TIMESTAMP) {
371			ip6_savecontrol(last, &opts, ip6, m);
372		}
373
374		m_adj(m, off + sizeof(struct udphdr));
375		if (sbappendaddr(&last->in6p_socket->so_rcv,
376				(struct sockaddr *)&udp_in6,
377				m, opts) == 0) {
378			udp6stat.udp6s_fullsock++;
379			goto bad;
380		}
381		sorwakeup(last->in6p_socket);
382		return IPPROTO_DONE;
383	}
384	/*
385	 * Locate pcb for datagram.
386	 */
387	in6p = udp6_last_in6pcb;
388	if (in6p->in6p_lport != uh->uh_dport ||
389	   in6p->in6p_fport != uh->uh_sport ||
390	   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src) ||
391	   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) {
392		in6p = in6_pcblookup(&udb6,
393				     &ip6->ip6_src, uh->uh_sport,
394				     &ip6->ip6_dst, uh->uh_dport,
395				     IN6PLOOKUP_WILDCARD);
396		if (in6p)
397			udp6_last_in6pcb = in6p;
398		udp6stat.udp6ps_pcbcachemiss++;
399	}
400	if (in6p == 0) {
401		udp6stat.udp6s_noport++;
402		if (m->m_flags & M_MCAST) {
403			udp6stat.udp6s_noportmcast++;
404			goto bad;
405		}
406		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
407		return IPPROTO_DONE;
408	}
409#ifdef IPSEC
410	/*
411	 * Check AH/ESP integrity.
412	 */
413	if (in6p != NULL && ipsec6_in_reject(m, in6p)) {
414		ipsec6stat.in_polvio++;
415		goto bad;
416	}
417#endif /*IPSEC*/
418
419	/*
420	 * Construct sockaddr format source address.
421	 * Stuff source address and datagram in user buffer.
422	 */
423	bzero(&udp_in6, sizeof(udp_in6));
424	udp_in6.sin6_len = sizeof(struct sockaddr_in6);
425	udp_in6.sin6_family = AF_INET6;
426	udp_in6.sin6_port = uh->uh_sport;
427	/* KAME hack: recover scopeid */
428	(void)in6_recoverscope(&udp_in6, &ip6->ip6_src, m->m_pkthdr.rcvif);
429	if (in6p->in6p_flags & IN6P_CONTROLOPTS
430	 || in6p->in6p_socket->so_options & SO_TIMESTAMP) {
431		ip6_savecontrol(in6p, &opts, ip6, m);
432	}
433
434	m_adj(m, off + sizeof(struct udphdr));
435	if (sbappendaddr(&in6p->in6p_socket->so_rcv,
436			(struct sockaddr *)&udp_in6,
437			m, opts) == 0) {
438		udp6stat.udp6s_fullsock++;
439		goto bad;
440	}
441	sorwakeup(in6p->in6p_socket);
442	return IPPROTO_DONE;
443bad:
444	if (m)
445		m_freem(m);
446	if (opts)
447		m_freem(opts);
448	return IPPROTO_DONE;
449}
450#endif
451
452/*
453 * Notify a udp user of an asynchronous error;
454 * just wake up so that he can collect error status.
455 */
456static	void
457udp6_notify(in6p, errno)
458	struct in6pcb *in6p;
459	int errno;
460{
461	in6p->in6p_socket->so_error = errno;
462	sorwakeup(in6p->in6p_socket);
463	sowwakeup(in6p->in6p_socket);
464}
465
466void
467udp6_ctlinput(cmd, sa, d)
468	int cmd;
469	struct sockaddr *sa;
470	void *d;
471{
472	struct udphdr uh;
473	struct ip6_hdr *ip6;
474	struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)sa;
475	struct mbuf *m;
476	int off;
477	void *cmdarg;
478	struct ip6ctlparam *ip6cp = NULL;
479	const struct sockaddr_in6 *sa6_src = NULL;
480	void (*notify) __P((struct in6pcb *, int)) = udp6_notify;
481	struct udp_portonly {
482		u_int16_t uh_sport;
483		u_int16_t uh_dport;
484	} *uhp;
485
486	if (sa->sa_family != AF_INET6 ||
487	    sa->sa_len != sizeof(struct sockaddr_in6))
488		return;
489
490	if ((unsigned)cmd >= PRC_NCMDS)
491		return;
492	if (PRC_IS_REDIRECT(cmd))
493		notify = in6_rtchange, d = NULL;
494	else if (cmd == PRC_HOSTDEAD)
495		d = NULL;
496	else if (cmd == PRC_MSGSIZE)
497		; /* special code is present, see below */
498	else if (inet6ctlerrmap[cmd] == 0)
499		return;
500
501	/* if the parameter is from icmp6, decode it. */
502	if (d != NULL) {
503		ip6cp = (struct ip6ctlparam *)d;
504		m = ip6cp->ip6c_m;
505		ip6 = ip6cp->ip6c_ip6;
506		off = ip6cp->ip6c_off;
507		cmdarg = ip6cp->ip6c_cmdarg;
508		sa6_src = ip6cp->ip6c_src;
509	} else {
510		m = NULL;
511		ip6 = NULL;
512		cmdarg = NULL;
513		sa6_src = &sa6_any;
514	}
515
516	if (ip6) {
517		/*
518		 * XXX: We assume that when IPV6 is non NULL,
519		 * M and OFF are valid.
520		 */
521
522		/* check if we can safely examine src and dst ports */
523		if (m->m_pkthdr.len < off + sizeof(*uhp)) {
524			if (cmd == PRC_MSGSIZE)
525				icmp6_mtudisc_update((struct ip6ctlparam *)d, 0);
526			return;
527		}
528
529		bzero(&uh, sizeof(uh));
530		m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
531
532		if (cmd == PRC_MSGSIZE) {
533			int valid = 0;
534
535			/*
536			 * Check to see if we have a valid UDP socket
537			 * corresponding to the address in the ICMPv6 message
538			 * payload.
539			 */
540			if (in6_pcblookup_connect(&udb6, &sa6->sin6_addr,
541			    uh.uh_dport, (struct in6_addr *)&sa6_src->sin6_addr,
542			    uh.uh_sport, 0))
543				valid++;
544#if 0
545			/*
546			 * As the use of sendto(2) is fairly popular,
547			 * we may want to allow non-connected pcb too.
548			 * But it could be too weak against attacks...
549			 * We should at least check if the local address (= s)
550			 * is really ours.
551			 */
552			else if (in6_pcblookup_bind(&udb6, &sa6->sin6_addr,
553						    uh.uh_dport, 0))
554				valid++;
555#endif
556
557			/*
558			 * Depending on the value of "valid" and routing table
559			 * size (mtudisc_{hi,lo}wat), we will:
560			 * - recalcurate the new MTU and create the
561			 *   corresponding routing entry, or
562			 * - ignore the MTU change notification.
563			 */
564			icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
565
566			/*
567			 * regardless of if we called icmp6_mtudisc_update(),
568			 * we need to call in6_pcbnotify(), to notify path
569			 * MTU change to the userland (2292bis-02), because
570			 * some unconnected sockets may share the same
571			 * destination and want to know the path MTU.
572			 */
573		}
574
575		(void) in6_pcbnotify(&udb6, sa, uh.uh_dport,
576		    (struct sockaddr *)sa6_src, uh.uh_sport, cmd, cmdarg,
577		    notify);
578	} else {
579		(void) in6_pcbnotify(&udb6, sa, 0, (struct sockaddr *)sa6_src,
580		    0, cmd, cmdarg, notify);
581	}
582}
583
584extern	int udp6_sendspace;
585extern	int udp6_recvspace;
586
587int
588udp6_usrreq(so, req, m, addr6, control, p)
589	struct socket *so;
590	int req;
591	struct mbuf *m, *addr6, *control;
592	struct proc *p;
593{
594	struct	in6pcb *in6p = sotoin6pcb(so);
595	int	error = 0;
596	int	s;
597
598	/*
599	 * MAPPED_ADDR implementation info:
600	 *  Mapped addr support for PRU_CONTROL is not necessary.
601	 *  Because typical user of PRU_CONTROL is such as ifconfig,
602	 *  and they don't associate any addr to their socket.  Then
603	 *  socket family is only hint about the PRU_CONTROL'ed address
604	 *  family, especially when getting addrs from kernel.
605	 *  So AF_INET socket need to be used to control AF_INET addrs,
606	 *  and AF_INET6 socket for AF_INET6 addrs.
607	 */
608	if (req == PRU_CONTROL)
609		return(in6_control(so, (u_long)m, (caddr_t)addr6,
610				   (struct ifnet *)control, p));
611
612	if (req == PRU_PURGEIF) {
613		in6_purgeif((struct ifnet *)control);
614		in6_pcbpurgeif(&udb6, (struct ifnet *)control);
615		return (0);
616	}
617
618	if (in6p == NULL && req != PRU_ATTACH) {
619		error = EINVAL;
620		goto release;
621	}
622
623	switch (req) {
624	case PRU_ATTACH:
625		/*
626		 * MAPPED_ADDR implementation spec:
627		 *  Always attach for IPv6,
628		 *  and only when necessary for IPv4.
629		 */
630		if (in6p != NULL) {
631			error = EINVAL;
632			break;
633		}
634		s = splsoftnet();
635		error = in6_pcballoc(so, &udb6);
636		splx(s);
637		if (error)
638			break;
639		error = soreserve(so, udp6_sendspace, udp6_recvspace);
640		if (error)
641			break;
642		in6p = sotoin6pcb(so);
643		in6p->in6p_cksum = -1;	/* just to be sure */
644#ifdef IPSEC
645		error = ipsec_init_policy(so, &in6p->in6p_sp);
646		if (error != 0) {
647			in6_pcbdetach(in6p);
648			break;
649		}
650#endif /*IPSEC*/
651		break;
652
653	case PRU_DETACH:
654		udp6_detach(in6p);
655		break;
656
657	case PRU_BIND:
658		s = splsoftnet();
659		error = in6_pcbbind(in6p, addr6, p);
660		splx(s);
661		break;
662
663	case PRU_LISTEN:
664		error = EOPNOTSUPP;
665		break;
666
667	case PRU_CONNECT:
668		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
669			error = EISCONN;
670			break;
671		}
672		s = splsoftnet();
673		error = in6_pcbconnect(in6p, addr6);
674		if (ip6_auto_flowlabel) {
675			in6p->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
676			in6p->in6p_flowinfo |=
677				(htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK);
678		}
679		splx(s);
680		if (error == 0)
681			soisconnected(so);
682		break;
683
684	case PRU_CONNECT2:
685		error = EOPNOTSUPP;
686		break;
687
688	case PRU_ACCEPT:
689		error = EOPNOTSUPP;
690		break;
691
692	case PRU_DISCONNECT:
693		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
694			error = ENOTCONN;
695			break;
696		}
697		s = splsoftnet();
698		in6_pcbdisconnect(in6p);
699		bzero((caddr_t)&in6p->in6p_laddr, sizeof(in6p->in6p_laddr));
700		splx(s);
701		so->so_state &= ~SS_ISCONNECTED;		/* XXX */
702		break;
703
704	case PRU_SHUTDOWN:
705		socantsendmore(so);
706		break;
707
708	case PRU_SEND:
709		return(udp6_output(in6p, m, addr6, control, p));
710
711	case PRU_ABORT:
712		soisdisconnected(so);
713		udp6_detach(in6p);
714		break;
715
716	case PRU_SOCKADDR:
717		in6_setsockaddr(in6p, addr6);
718		break;
719
720	case PRU_PEERADDR:
721		in6_setpeeraddr(in6p, addr6);
722		break;
723
724	case PRU_SENSE:
725		/*
726		 * stat: don't bother with a blocksize
727		 */
728		return(0);
729
730	case PRU_SENDOOB:
731	case PRU_FASTTIMO:
732	case PRU_SLOWTIMO:
733	case PRU_PROTORCV:
734	case PRU_PROTOSEND:
735		error = EOPNOTSUPP;
736		break;
737
738	case PRU_RCVD:
739	case PRU_RCVOOB:
740		return(EOPNOTSUPP);	/* do not free mbuf's */
741
742	default:
743		panic("udp6_usrreq");
744	}
745
746release:
747	if (control)
748		m_freem(control);
749	if (m)
750		m_freem(m);
751	return(error);
752}
753
754static void
755udp6_detach(in6p)
756	struct in6pcb *in6p;
757{
758	int s = splsoftnet();
759
760	if (in6p == udp6_last_in6pcb)
761		udp6_last_in6pcb = &udb6;
762	in6_pcbdetach(in6p);
763	splx(s);
764}
765
766#include <uvm/uvm_extern.h>
767#include <sys/sysctl.h>
768
769int
770udp6_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
771	int *name;
772	u_int namelen;
773	void *oldp;
774	size_t *oldlenp;
775	void *newp;
776	size_t newlen;
777{
778	/* All sysctl names at this level are terminal. */
779	if (namelen != 1)
780		return ENOTDIR;
781
782	switch (name[0]) {
783
784	case UDP6CTL_SENDSPACE:
785		return sysctl_int(oldp, oldlenp, newp, newlen,
786		    &udp6_sendspace);
787	case UDP6CTL_RECVSPACE:
788		return sysctl_int(oldp, oldlenp, newp, newlen,
789		    &udp6_recvspace);
790	default:
791		return ENOPROTOOPT;
792	}
793	/* NOTREACHED */
794}
795