xref: /freebsd/sys/netinet6/udp6_usrreq.c (revision 5129159789cc9d7bc514e4546b88e3427695002d)
1 /*
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * Copyright (c) 1982, 1986, 1989, 1993
32  *	The Regents of the University of California.  All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  * 3. All advertising materials mentioning features or use of this software
43  *    must display the following acknowledgement:
44  *	This product includes software developed by the University of
45  *	California, Berkeley and its contributors.
46  * 4. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  *
62  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
63  * $FreeBSD$
64  */
65 
66 #include <sys/param.h>
67 #include <sys/kernel.h>
68 #include <sys/malloc.h>
69 #include <sys/mbuf.h>
70 #include <sys/protosw.h>
71 #include <sys/socket.h>
72 #include <sys/socketvar.h>
73 #include <sys/sysctl.h>
74 #include <sys/errno.h>
75 #include <sys/stat.h>
76 #include <sys/systm.h>
77 #include <sys/syslog.h>
78 #include <sys/proc.h>
79 
80 #include <net/if.h>
81 #include <net/route.h>
82 #include <net/if_types.h>
83 
84 #include <netinet/in.h>
85 #include <netinet/in_systm.h>
86 #include <netinet/ip.h>
87 #include <netinet/in_pcb.h>
88 #include <netinet/in_var.h>
89 #include <netinet/ip_var.h>
90 #include <netinet/udp.h>
91 #include <netinet/udp_var.h>
92 #include <netinet6/ip6.h>
93 #include <netinet6/ip6_var.h>
94 #include <netinet6/in6_pcb.h>
95 #include <netinet6/icmp6.h>
96 #include <netinet6/udp6_var.h>
97 #include <netinet6/ip6protosw.h>
98 
99 #ifdef IPSEC
100 #include <netinet6/ipsec.h>
101 #endif /*IPSEC*/
102 
103 #include "faith.h"
104 
105 /*
106  * UDP protocol inplementation.
107  * Per RFC 768, August, 1980.
108  */
109 
110 extern	struct protosw inetsw[];
111 static	int in6_mcmatch __P((struct inpcb *, struct in6_addr *, struct ifnet *));
112 static	int udp6_detach __P((struct socket *so));
113 
114 static int
115 in6_mcmatch(in6p, ia6, ifp)
116 	struct inpcb *in6p;
117 	register struct in6_addr *ia6;
118 	struct ifnet *ifp;
119 {
120 	struct ip6_moptions *im6o = in6p->in6p_moptions;
121 	struct in6_multi_mship *imm;
122 
123 	if (im6o == NULL)
124 		return 0;
125 
126 	for (imm = im6o->im6o_memberships.lh_first; imm != NULL;
127 	     imm = imm->i6mm_chain.le_next) {
128 		if ((ifp == NULL ||
129 		     imm->i6mm_maddr->in6m_ifp == ifp) &&
130 		    IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
131 				       ia6))
132 			return 1;
133 	}
134 	return 0;
135 }
136 
137 int
138 udp6_input(mp, offp, proto)
139 	struct mbuf **mp;
140 	int *offp, proto;
141 {
142 	struct mbuf *m = *mp;
143 	register struct ip6_hdr *ip6;
144 	register struct udphdr *uh;
145 	register struct inpcb *in6p;
146 	struct	mbuf *opts = 0;
147 	int off = *offp;
148 	int plen, ulen;
149 	struct sockaddr_in6 udp_in6;
150 
151 #if defined(NFAITH) && 0 < NFAITH
152 	if (m->m_pkthdr.rcvif) {
153 		if (m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
154 			/* XXX send icmp6 host/port unreach? */
155 			m_freem(m);
156 			return IPPROTO_DONE;
157 		}
158 	}
159 #endif
160 	udpstat.udps_ipackets++;
161 
162 	IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
163 
164 	ip6 = mtod(m, struct ip6_hdr *);
165 	plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
166 	uh = (struct udphdr *)((caddr_t)ip6 + off);
167 	ulen = ntohs((u_short)uh->uh_ulen);
168 
169 	if (plen != ulen) {
170 		udpstat.udps_badlen++;
171 		goto bad;
172 	}
173 
174 	/*
175 	 * Checksum extended UDP header and data.
176 	 */
177 	if (uh->uh_sum == 0)
178 		udpstat.udps_nosum++;
179 	else if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
180 		udpstat.udps_badsum++;
181 		goto bad;
182 	}
183 
184 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
185 		struct	inpcb *last;
186 
187 		/*
188 		 * Deliver a multicast datagram to all sockets
189 		 * for which the local and remote addresses and ports match
190 		 * those of the incoming datagram.  This allows more than
191 		 * one process to receive multicasts on the same port.
192 		 * (This really ought to be done for unicast datagrams as
193 		 * well, but that would cause problems with existing
194 		 * applications that open both address-specific sockets and
195 		 * a wildcard socket listening to the same port -- they would
196 		 * end up receiving duplicates of every unicast datagram.
197 		 * Those applications open the multiple sockets to overcome an
198 		 * inadequacy of the UDP socket interface, but for backwards
199 		 * compatibility we avoid the problem here rather than
200 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
201 		 */
202 
203 		/*
204 		 * In a case that laddr should be set to the link-local
205 		 * address (this happens in RIPng), the multicast address
206 		 * specified in the received packet does not match with
207 		 * laddr. To cure this situation, the matching is relaxed
208 		 * if the receiving interface is the same as one specified
209 		 * in the socket and if the destination multicast address
210 		 * matches one of the multicast groups specified in the socket.
211 		 */
212 
213 		/*
214 		 * Construct sockaddr format source address.
215 		 */
216 		init_sin6(&udp_in6, m); /* general init */
217 		udp_in6.sin6_port = uh->uh_sport;
218 		/*
219 		 * KAME note: usually we drop udphdr from mbuf here.
220 		 * We need udphdr for IPsec processing so we do that later.
221 		 */
222 
223 		/*
224 		 * Locate pcb(s) for datagram.
225 		 * (Algorithm copied from raw_intr().)
226 		 */
227 		last = NULL;
228 		LIST_FOREACH(in6p, &udb, inp_list) {
229 			if ((in6p->inp_vflag & INP_IPV6) == NULL)
230 				continue;
231 			if (in6p->in6p_lport != uh->uh_dport)
232 				continue;
233 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
234 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
235 							&ip6->ip6_dst) &&
236 				    !in6_mcmatch(in6p, &ip6->ip6_dst,
237 						 m->m_pkthdr.rcvif))
238 					continue;
239 			}
240 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
241 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
242 							&ip6->ip6_src) ||
243 				   in6p->in6p_fport != uh->uh_sport)
244 					continue;
245 			}
246 
247 			if (last != NULL) {
248 				struct	mbuf *n;
249 
250 #ifdef IPSEC
251 				/*
252 				 * Check AH/ESP integrity.
253 				 */
254 				if (last != NULL &&
255 				    ipsec6_in_reject_so(m, last->inp_socket)) {
256 					ipsec6stat.in_polvio++;
257 					/* do not inject data into pcb */
258 				} else
259 #endif /*IPSEC*/
260 				if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
261 					/*
262 					 * KAME NOTE: do not
263 					 * m_copy(m, offset, ...) above.
264 					 * sbappendaddr() expects M_PKTHDR,
265 					 * and m_copy() will copy M_PKTHDR
266 					 * only if offset is 0.
267 					 */
268 					if (last->in6p_flags & IN6P_CONTROLOPTS
269 					    || last->in6p_socket->so_options & SO_TIMESTAMP)
270 						ip6_savecontrol(last, &opts,
271 								ip6, n);
272 					m_adj(n, off + sizeof(struct udphdr));
273 					if (sbappendaddr(&last->in6p_socket->so_rcv,
274 							(struct sockaddr *)&udp_in6,
275 							n, opts) == 0) {
276 						m_freem(n);
277 						if (opts)
278 							m_freem(opts);
279 						udpstat.udps_fullsock++;
280 					} else
281 						sorwakeup(last->in6p_socket);
282 					opts = 0;
283 				}
284 			}
285 			last = in6p;
286 			/*
287 			 * Don't look for additional matches if this one does
288 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
289 			 * socket options set.  This heuristic avoids searching
290 			 * through all pcbs in the common case of a non-shared
291 			 * port.  It assumes that an application will never
292 			 * clear these options after setting them.
293 			 */
294 			if ((last->in6p_socket->so_options &
295 			     (SO_REUSEPORT|SO_REUSEADDR)) == 0)
296 				break;
297 		}
298 
299 		if (last == NULL) {
300 			/*
301 			 * No matching pcb found; discard datagram.
302 			 * (No need to send an ICMP Port Unreachable
303 			 * for a broadcast or multicast datgram.)
304 			 */
305 			udpstat.udps_noport++;
306 			udpstat.udps_noportmcast++;
307 			goto bad;
308 		}
309 #ifdef IPSEC
310 		/*
311 		 * Check AH/ESP integrity.
312 		 */
313 		if (last != NULL && ipsec6_in_reject_so(m, last->inp_socket)) {
314 			ipsec6stat.in_polvio++;
315 			goto bad;
316 		}
317 #endif /*IPSEC*/
318 		if (last->in6p_flags & IN6P_CONTROLOPTS
319 		    || last->in6p_socket->so_options & SO_TIMESTAMP)
320 			ip6_savecontrol(last, &opts, ip6, m);
321 
322 		m_adj(m, off + sizeof(struct udphdr));
323 		if (sbappendaddr(&last->in6p_socket->so_rcv,
324 				(struct sockaddr *)&udp_in6,
325 				m, opts) == 0) {
326 			udpstat.udps_fullsock++;
327 			goto bad;
328 		}
329 		sorwakeup(last->in6p_socket);
330 		return IPPROTO_DONE;
331 	}
332 	/*
333 	 * Locate pcb for datagram.
334 	 */
335 	in6p = in6_pcblookup_hash(&udbinfo, &ip6->ip6_src, uh->uh_sport,
336 				  &ip6->ip6_dst, uh->uh_dport, 1,
337 				  m->m_pkthdr.rcvif);
338 	if (in6p == 0) {
339 		if (log_in_vain) {
340 			char buf[INET6_ADDRSTRLEN];
341 
342 			strcpy(buf, ip6_sprintf(&ip6->ip6_dst));
343 			log(LOG_INFO,
344 			    "Connection attempt to UDP %s:%d from %s:%d\n",
345 			    buf, ntohs(uh->uh_dport),
346 			    ip6_sprintf(&ip6->ip6_src), ntohs(uh->uh_sport));
347 		}
348 		udpstat.udps_noport++;
349 		if (m->m_flags & M_MCAST) {
350 			printf("UDP6: M_MCAST is set in a unicast packet.\n");
351 			udpstat.udps_noportmcast++;
352 			goto bad;
353 		}
354 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
355 		return IPPROTO_DONE;
356 	}
357 #ifdef IPSEC
358 	/*
359 	 * Check AH/ESP integrity.
360 	 */
361 	if (in6p != NULL && ipsec6_in_reject_so(m, in6p->in6p_socket)) {
362 		ipsec6stat.in_polvio++;
363 		goto bad;
364 	}
365 #endif /*IPSEC*/
366 
367 	/*
368 	 * Construct sockaddr format source address.
369 	 * Stuff source address and datagram in user buffer.
370 	 */
371 	init_sin6(&udp_in6, m); /* general init */
372 	udp_in6.sin6_port = uh->uh_sport;
373 	if (in6p->in6p_flags & IN6P_CONTROLOPTS
374 	    || in6p->in6p_socket->so_options & SO_TIMESTAMP)
375 		ip6_savecontrol(in6p, &opts, ip6, m);
376 	m_adj(m, off + sizeof(struct udphdr));
377 	if (sbappendaddr(&in6p->in6p_socket->so_rcv,
378 			(struct sockaddr *)&udp_in6,
379 			m, opts) == 0) {
380 		udpstat.udps_fullsock++;
381 		goto bad;
382 	}
383 	sorwakeup(in6p->in6p_socket);
384 	return IPPROTO_DONE;
385 bad:
386 	if (m)
387 		m_freem(m);
388 	if (opts)
389 		m_freem(opts);
390 	return IPPROTO_DONE;
391 }
392 
393 void
394 udp6_ctlinput(cmd, sa, d)
395 	int cmd;
396 	struct sockaddr *sa;
397 	void *d;
398 {
399 	register struct udphdr *uhp;
400 	struct udphdr uh;
401 	struct sockaddr_in6 sa6;
402 	struct ip6_hdr *ip6;
403 	struct mbuf *m;
404 	int off;
405 
406 	if (sa->sa_family != AF_INET6 ||
407 	    sa->sa_len != sizeof(struct sockaddr_in6))
408 		return;
409 
410 	if (!PRC_IS_REDIRECT(cmd) &&
411 	    ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0))
412 		return;
413 
414 	/* if the parameter is from icmp6, decode it. */
415 	if (d != NULL) {
416 		struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d;
417 		m = ip6cp->ip6c_m;
418 		ip6 = ip6cp->ip6c_ip6;
419 		off = ip6cp->ip6c_off;
420 	} else {
421 		m = NULL;
422 		ip6 = NULL;
423 	}
424 
425 	/* translate addresses into internal form */
426 	sa6 = *(struct sockaddr_in6 *)sa;
427 	if (IN6_IS_ADDR_LINKLOCAL(&sa6.sin6_addr))
428 		sa6.sin6_addr.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
429 
430 	if (ip6) {
431 		/*
432 		 * XXX: We assume that when IPV6 is non NULL,
433 		 * M and OFF are valid.
434 		 */
435 		struct in6_addr s;
436 
437 		/* translate addresses into internal form */
438 		memcpy(&s, &ip6->ip6_src, sizeof(s));
439 		if (IN6_IS_ADDR_LINKLOCAL(&s))
440 			s.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
441 
442 		if (m->m_len < off + sizeof(uh)) {
443 			/*
444 			 * this should be rare case,
445 			 * so we compromise on this copy...
446 			 */
447 			m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
448 			uhp = &uh;
449 		} else
450 			uhp = (struct udphdr *)(mtod(m, caddr_t) + off);
451 		(void) in6_pcbnotify(&udb, (struct sockaddr *)&sa6,
452 				     uhp->uh_dport, &s,
453 				     uhp->uh_sport, cmd, udp_notify);
454 	} else
455 		(void) in6_pcbnotify(&udb, (struct sockaddr *)&sa6, 0,
456 				     &zeroin6_addr, 0, cmd, udp_notify);
457 }
458 
459 static int
460 udp6_getcred SYSCTL_HANDLER_ARGS
461 {
462 	struct sockaddr_in6 addrs[2];
463 	struct inpcb *inp;
464 	int error, s;
465 
466 	error = suser(req->p);
467 	if (error)
468 		return (error);
469 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
470 	if (error)
471 		return (error);
472 	s = splnet();
473 	inp = in6_pcblookup_hash(&udbinfo, &addrs[1].sin6_addr,
474 				 addrs[1].sin6_port,
475 				 &addrs[0].sin6_addr, addrs[0].sin6_port,
476 				 1, NULL);
477 	if (!inp || !inp->inp_socket || !inp->inp_socket->so_cred) {
478 		error = ENOENT;
479 		goto out;
480 	}
481 	error = SYSCTL_OUT(req, inp->inp_socket->so_cred,
482 			   sizeof(struct ucred));
483 
484 out:
485 	splx(s);
486 	return (error);
487 }
488 
489 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW,
490 	    0, 0,
491 	    udp6_getcred, "S,ucred", "Get the ucred of a UDP6 connection");
492 
493 int
494 udp6_output(in6p, m, addr6, control, p)
495 	register struct inpcb *in6p;
496 	struct mbuf *m;
497 	struct sockaddr *addr6;
498 	struct mbuf *control;
499 	struct proc *p;
500 {
501 	register int ulen = m->m_pkthdr.len;
502 	int plen = sizeof(struct udphdr) + ulen;
503 	struct ip6_hdr *ip6;
504 	struct udphdr *udp6;
505 	struct	in6_addr laddr6;
506 	int s = 0, error = 0;
507 	struct ip6_pktopts opt, *stickyopt = in6p->in6p_outputopts;
508 
509 	if (control) {
510 		if ((error = ip6_setpktoptions(control, &opt, suser(p))) != 0)
511 			goto release;
512 		in6p->in6p_outputopts = &opt;
513 	}
514 
515 	if (addr6) {
516 		laddr6 = in6p->in6p_laddr;
517 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
518 			error = EISCONN;
519 			goto release;
520 		}
521 		/*
522 		 * Must block input while temporarily connected.
523 		 */
524 		s = splnet();
525 		/*
526 		 * XXX: the user might want to overwrite the local address
527 		 * via an ancillary data.
528 		 */
529 		bzero(&in6p->in6p_laddr, sizeof(struct in6_addr));
530 		error = in6_pcbconnect(in6p, addr6, p);
531 		if (error) {
532 			splx(s);
533 			goto release;
534 		}
535 	} else {
536 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
537 			error = ENOTCONN;
538 			goto release;
539 		}
540 	}
541 	/*
542 	 * Calculate data length and get a mbuf
543 	 * for UDP and IP6 headers.
544 	 */
545 	M_PREPEND(m, sizeof(struct ip6_hdr) + sizeof(struct udphdr),
546 		  M_DONTWAIT);
547 	if (m == 0) {
548 		error = ENOBUFS;
549 		if (addr6)
550 			splx(s);
551 		goto release;
552 	}
553 
554 	/*
555 	 * Stuff checksum and output datagram.
556 	 */
557 	ip6 = mtod(m, struct ip6_hdr *);
558 	ip6->ip6_flow	= in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
559 	ip6->ip6_vfc 	= IPV6_VERSION;
560 	/* ip6_plen will be filled in ip6_output. */
561 	ip6->ip6_nxt	= IPPROTO_UDP;
562 	ip6->ip6_hlim   = in6_selecthlim(in6p,
563 					 in6p->in6p_route.ro_rt ?
564 					 in6p->in6p_route.ro_rt->rt_ifp :
565 					 NULL);
566 	ip6->ip6_src	= in6p->in6p_laddr;
567 	ip6->ip6_dst	= in6p->in6p_faddr;
568 
569 	udp6 = (struct udphdr *)(ip6 + 1);
570 	udp6->uh_sport = in6p->in6p_lport;
571 	udp6->uh_dport = in6p->in6p_fport;
572 	udp6->uh_ulen  = htons((u_short)plen);
573 	udp6->uh_sum   = 0;
574 
575 	if ((udp6->uh_sum = in6_cksum(m, IPPROTO_UDP,
576 					sizeof(struct ip6_hdr), plen)) == 0) {
577 		udp6->uh_sum = 0xffff;
578 	}
579 
580 	udpstat.udps_opackets++;
581 
582 #ifdef IPSEC
583 	m->m_pkthdr.rcvif = (struct ifnet *)in6p->in6p_socket;
584 #endif /*IPSEC*/
585 	error = ip6_output(m, in6p->in6p_outputopts, &in6p->in6p_route,
586 			    0, in6p->in6p_moptions, NULL);
587 
588 	if (addr6) {
589 		in6_pcbdisconnect(in6p);
590 		in6p->in6p_laddr = laddr6;
591 		splx(s);
592 	}
593 	goto releaseopt;
594 
595 release:
596 	m_freem(m);
597 
598 releaseopt:
599 	if (control) {
600 		in6p->in6p_outputopts = stickyopt;
601 		m_freem(control);
602 	}
603 	return(error);
604 }
605 
606 static int
607 udp6_abort(struct socket *so)
608 {
609 	struct inpcb *inp;
610 	int s;
611 
612 	inp = sotoinpcb(so);
613 	if (inp == 0)
614 		return EINVAL;	/* ??? possible? panic instead? */
615 	soisdisconnected(so);
616 	s = splnet();
617 	in6_pcbdetach(inp);
618 	splx(s);
619 	return 0;
620 }
621 
622 static int
623 udp6_attach(struct socket *so, int proto, struct proc *p)
624 {
625 	struct inpcb *inp;
626 	int s, error;
627 
628 	inp = sotoinpcb(so);
629 	if (inp != 0)
630 		return EINVAL;
631 
632 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
633 		error = soreserve(so, udp_sendspace, udp_recvspace);
634 		if (error)
635 			return error;
636 	}
637 	s = splnet();
638 	error = in_pcballoc(so, &udbinfo, p);
639 	splx(s);
640 	if (error)
641 		return error;
642 	inp = (struct inpcb *)so->so_pcb;
643 	inp->inp_vflag |= INP_IPV6;
644 	inp->in6p_hops = -1;	/* use kernel default */
645 	inp->in6p_cksum = -1;	/* just to be sure */
646 #ifdef IPSEC
647 	error = ipsec_init_policy(so, &inp->in6p_sp);
648 	if (error != 0) {
649 		in6_pcbdetach(inp);
650 		return (error);
651 	}
652 #endif /*IPSEC*/
653 	return 0;
654 }
655 
656 static int
657 udp6_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
658 {
659 	struct inpcb *inp;
660 	int s, error;
661 
662 	inp = sotoinpcb(so);
663 	if (inp == 0)
664 		return EINVAL;
665 
666 	inp->inp_vflag &= ~INP_IPV4;
667 	inp->inp_vflag |= INP_IPV6;
668 	if (ip6_mapped_addr_on && (inp->inp_flags & IN6P_BINDV6ONLY) == NULL) {
669 		struct sockaddr_in6 *sin6_p;
670 
671 		sin6_p = (struct sockaddr_in6 *)nam;
672 
673 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
674 			inp->inp_vflag |= INP_IPV4;
675 		else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
676 			struct sockaddr_in sin;
677 
678 			in6_sin6_2_sin(&sin, sin6_p);
679 			inp->inp_vflag |= INP_IPV4;
680 			inp->inp_vflag &= ~INP_IPV6;
681 			s = splnet();
682 			error = in_pcbbind(inp, (struct sockaddr *)&sin, p);
683 			splx(s);
684 			return error;
685 		}
686 	}
687 
688 	s = splnet();
689 	error = in6_pcbbind(inp, nam, p);
690 	splx(s);
691 	return error;
692 }
693 
694 static int
695 udp6_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
696 {
697 	struct inpcb *inp;
698 	int s, error;
699 
700 	inp = sotoinpcb(so);
701 	if (inp == 0)
702 		return EINVAL;
703 
704 	if (ip6_mapped_addr_on) {
705 		struct sockaddr_in6 *sin6_p;
706 
707 		sin6_p = (struct sockaddr_in6 *)nam;
708 		if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
709 			struct sockaddr_in sin;
710 
711 			if (inp->inp_faddr.s_addr != INADDR_ANY)
712 				return EISCONN;
713 			in6_sin6_2_sin(&sin, sin6_p);
714 			s = splnet();
715 			error = in_pcbconnect(inp, (struct sockaddr *)&sin, p);
716 			splx(s);
717 			if (error == NULL) {
718 				inp->inp_vflag |= INP_IPV4;
719 				inp->inp_vflag &= ~INP_IPV6;
720 				soisconnected(so);
721 			}
722 			return error;
723 		}
724 	}
725 
726 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
727 		return EISCONN;
728 	s = splnet();
729 	error = in6_pcbconnect(inp, nam, p);
730 	if (ip6_auto_flowlabel) {
731 		inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
732 		inp->in6p_flowinfo |=
733 			(htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK);
734 	}
735 	splx(s);
736 	if (error == NULL) {
737 		if (ip6_mapped_addr_on) { /* should be non mapped addr */
738 			inp->inp_vflag &= ~INP_IPV4;
739 			inp->inp_vflag |= INP_IPV6;
740 		}
741 		soisconnected(so);
742 	}
743 	return error;
744 }
745 
746 static int
747 udp6_detach(struct socket *so)
748 {
749 	struct inpcb *inp;
750 	int s;
751 
752 	inp = sotoinpcb(so);
753 	if (inp == 0)
754 		return EINVAL;
755 	s = splnet();
756 	in6_pcbdetach(inp);
757 	splx(s);
758 	return 0;
759 }
760 
761 static int
762 udp6_disconnect(struct socket *so)
763 {
764 	struct inpcb *inp;
765 	int s;
766 
767 	inp = sotoinpcb(so);
768 	if (inp == 0)
769 		return EINVAL;
770 
771 	if (inp->inp_vflag & INP_IPV4) {
772 		struct pr_usrreqs *pru;
773 
774 		pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
775 		return ((*pru->pru_disconnect)(so));
776 	}
777 
778 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
779 		return ENOTCONN;
780 
781 	s = splnet();
782 	in6_pcbdisconnect(inp);
783 	inp->in6p_laddr = in6addr_any;
784 	splx(s);
785 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
786 	return 0;
787 }
788 
789 static int
790 udp6_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
791 	  struct mbuf *control, struct proc *p)
792 {
793 	struct inpcb *inp;
794 
795 	inp = sotoinpcb(so);
796 	if (inp == 0) {
797 		m_freem(m);
798 		return EINVAL;
799 	}
800 
801 	if (ip6_mapped_addr_on) {
802 		int hasv4addr;
803 		struct sockaddr_in6 *sin6 = 0;
804 
805 		if (addr == 0)
806 			hasv4addr = (inp->inp_vflag & INP_IPV4);
807 		else {
808 			sin6 = (struct sockaddr_in6 *)addr;
809 			hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
810 				? 1 : 0;
811 		}
812 		if (hasv4addr) {
813 			struct pr_usrreqs *pru;
814 			int error;
815 
816 			if (sin6)
817 				in6_sin6_2_sin_in_sock(addr);
818 			pru = inetsw[ip_protox[IPPROTO_UDP]].pr_usrreqs;
819 			error = ((*pru->pru_send)(so, flags, m, addr, control,
820 						  p));
821 			/* addr will just be freed in sendit(). */
822 			return error;
823 		}
824 	}
825 
826 	return udp6_output(inp, m, addr, control, p);
827 }
828 
829 struct pr_usrreqs udp6_usrreqs = {
830 	udp6_abort, pru_accept_notsupp, udp6_attach, udp6_bind, udp6_connect,
831 	pru_connect2_notsupp, in6_control, udp6_detach, udp6_disconnect,
832 	pru_listen_notsupp, in6_mapped_peeraddr, pru_rcvd_notsupp,
833 	pru_rcvoob_notsupp, udp6_send, pru_sense_null, udp_shutdown,
834 	in6_mapped_sockaddr, sosend, soreceive, sopoll
835 };
836