xref: /openbsd-src/sys/netinet/udp_usrreq.c (revision a5429850edcc9dd5646cc8ddb251ed22eba08b09)
1 /*	$OpenBSD: udp_usrreq.c,v 1.302 2022/09/05 14:56:09 bluhm Exp $	*/
2 /*	$NetBSD: udp_usrreq.c,v 1.28 1996/03/16 23:54:03 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1988, 1990, 1993
6  *	The Regents of the University of California.  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 University 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 REGENTS 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 REGENTS 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  *	@(#)COPYRIGHT	1.1 (NRL) 17 January 1995
33  *
34  * NRL grants permission for redistribution and use in source and binary
35  * forms, with or without modification, of the software and documentation
36  * created at NRL provided that the following conditions are met:
37  *
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  * 3. All advertising materials mentioning features or use of this software
44  *    must display the following acknowledgements:
45  *	This product includes software developed by the University of
46  *	California, Berkeley and its contributors.
47  *	This product includes software developed at the Information
48  *	Technology Division, US Naval Research Laboratory.
49  * 4. Neither the name of the NRL 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  * THE SOFTWARE PROVIDED BY NRL IS PROVIDED BY NRL AND CONTRIBUTORS ``AS
54  * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
55  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
56  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL NRL OR
57  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
58  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
59  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
60  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
61  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
62  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
63  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
64  *
65  * The views and conclusions contained in the software and documentation
66  * are those of the authors and should not be interpreted as representing
67  * official policies, either expressed or implied, of the US Naval
68  * Research Laboratory (NRL).
69  */
70 
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/mbuf.h>
74 #include <sys/protosw.h>
75 #include <sys/socket.h>
76 #include <sys/socketvar.h>
77 #include <sys/sysctl.h>
78 #include <sys/domain.h>
79 
80 #include <net/if.h>
81 #include <net/if_var.h>
82 #include <net/if_media.h>
83 #include <net/route.h>
84 
85 #include <netinet/in.h>
86 #include <netinet/in_var.h>
87 #include <netinet/ip.h>
88 #include <netinet/in_pcb.h>
89 #include <netinet/ip_var.h>
90 #include <netinet/ip_icmp.h>
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93 
94 #ifdef IPSEC
95 #include <netinet/ip_ipsp.h>
96 #include <netinet/ip_esp.h>
97 #endif
98 
99 #ifdef INET6
100 #include <netinet6/in6_var.h>
101 #include <netinet6/ip6_var.h>
102 #include <netinet6/ip6protosw.h>
103 #endif /* INET6 */
104 
105 #include "pf.h"
106 #if NPF > 0
107 #include <net/pfvar.h>
108 #endif
109 
110 #ifdef PIPEX
111 #include <netinet/if_ether.h>
112 #include <net/pipex.h>
113 #endif
114 
115 /*
116  * UDP protocol implementation.
117  * Per RFC 768, August, 1980.
118  */
119 int	udpcksum = 1;
120 
121 u_int	udp_sendspace = 9216;		/* really max datagram size */
122 u_int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
123 					/* 40 1K datagrams */
124 
125 const struct pr_usrreqs udp_usrreqs = {
126 	.pru_attach	= udp_attach,
127 	.pru_detach	= udp_detach,
128 	.pru_lock	= udp_lock,
129 	.pru_unlock	= udp_unlock,
130 	.pru_bind	= udp_bind,
131 	.pru_connect	= udp_connect,
132 	.pru_disconnect	= udp_disconnect,
133 	.pru_shutdown	= udp_shutdown,
134 	.pru_send	= udp_send,
135 	.pru_abort	= udp_abort,
136 	.pru_control	= in_control,
137 	.pru_sockaddr	= in_sockaddr,
138 	.pru_peeraddr	= in_peeraddr,
139 };
140 
141 #ifdef INET6
142 const struct pr_usrreqs udp6_usrreqs = {
143 	.pru_attach	= udp_attach,
144 	.pru_detach	= udp_detach,
145 	.pru_lock	= udp_lock,
146 	.pru_unlock	= udp_unlock,
147 	.pru_bind	= udp_bind,
148 	.pru_connect	= udp_connect,
149 	.pru_disconnect	= udp_disconnect,
150 	.pru_shutdown	= udp_shutdown,
151 	.pru_send	= udp_send,
152 	.pru_abort	= udp_abort,
153 	.pru_control	= in6_control,
154 	.pru_sockaddr	= in6_sockaddr,
155 	.pru_peeraddr	= in6_peeraddr,
156 };
157 #endif
158 
159 const struct sysctl_bounded_args udpctl_vars[] = {
160 	{ UDPCTL_CHECKSUM, &udpcksum, 0, 1 },
161 	{ UDPCTL_RECVSPACE, &udp_recvspace, 0, INT_MAX },
162 	{ UDPCTL_SENDSPACE, &udp_sendspace, 0, INT_MAX },
163 };
164 
165 struct	inpcbtable udbtable;
166 struct	cpumem *udpcounters;
167 
168 void	udp_sbappend(struct inpcb *, struct mbuf *, struct ip *,
169 	    struct ip6_hdr *, int, struct udphdr *, struct sockaddr *,
170 	    u_int32_t);
171 int	udp_output(struct inpcb *, struct mbuf *, struct mbuf *, struct mbuf *);
172 void	udp_notify(struct inpcb *, int);
173 int	udp_sysctl_udpstat(void *, size_t *, void *);
174 
175 #ifndef	UDB_INITIAL_HASH_SIZE
176 #define	UDB_INITIAL_HASH_SIZE	128
177 #endif
178 
179 void
180 udp_init(void)
181 {
182 	udpcounters = counters_alloc(udps_ncounters);
183 	in_pcbinit(&udbtable, UDB_INITIAL_HASH_SIZE);
184 }
185 
186 int
187 udp_input(struct mbuf **mp, int *offp, int proto, int af)
188 {
189 	struct mbuf *m = *mp;
190 	int iphlen = *offp;
191 	struct ip *ip = NULL;
192 	struct udphdr *uh;
193 	struct inpcb *inp = NULL;
194 	struct ip save_ip;
195 	int len;
196 	u_int16_t savesum;
197 	union {
198 		struct sockaddr sa;
199 		struct sockaddr_in sin;
200 #ifdef INET6
201 		struct sockaddr_in6 sin6;
202 #endif /* INET6 */
203 	} srcsa, dstsa;
204 	struct ip6_hdr *ip6 = NULL;
205 	u_int32_t ipsecflowinfo = 0;
206 
207 	udpstat_inc(udps_ipackets);
208 
209 	IP6_EXTHDR_GET(uh, struct udphdr *, m, iphlen, sizeof(struct udphdr));
210 	if (!uh) {
211 		udpstat_inc(udps_hdrops);
212 		return IPPROTO_DONE;
213 	}
214 
215 	/* Check for illegal destination port 0 */
216 	if (uh->uh_dport == 0) {
217 		udpstat_inc(udps_noport);
218 		goto bad;
219 	}
220 
221 	/*
222 	 * Make mbuf data length reflect UDP length.
223 	 * If not enough data to reflect UDP length, drop.
224 	 */
225 	len = ntohs((u_int16_t)uh->uh_ulen);
226 	switch (af) {
227 	case AF_INET:
228 		if (m->m_pkthdr.len - iphlen != len) {
229 			if (len > (m->m_pkthdr.len - iphlen) ||
230 			    len < sizeof(struct udphdr)) {
231 				udpstat_inc(udps_badlen);
232 				goto bad;
233 			}
234 			m_adj(m, len - (m->m_pkthdr.len - iphlen));
235 		}
236 		ip = mtod(m, struct ip *);
237 		/*
238 		 * Save a copy of the IP header in case we want restore it
239 		 * for sending an ICMP error message in response.
240 		 */
241 		save_ip = *ip;
242 		break;
243 #ifdef INET6
244 	case AF_INET6:
245 		/* jumbograms */
246 		if (len == 0 && m->m_pkthdr.len - iphlen > 0xffff)
247 			len = m->m_pkthdr.len - iphlen;
248 		if (len != m->m_pkthdr.len - iphlen) {
249 			udpstat_inc(udps_badlen);
250 			goto bad;
251 		}
252 		ip6 = mtod(m, struct ip6_hdr *);
253 		break;
254 #endif /* INET6 */
255 	default:
256 		unhandled_af(af);
257 	}
258 
259 	/*
260 	 * Checksum extended UDP header and data.
261 	 * from W.R.Stevens: check incoming udp cksums even if
262 	 *	udpcksum is not set.
263 	 */
264 	savesum = uh->uh_sum;
265 	if (uh->uh_sum == 0) {
266 		udpstat_inc(udps_nosum);
267 #ifdef INET6
268 		/*
269 		 * In IPv6, the UDP checksum is ALWAYS used.
270 		 */
271 		if (ip6)
272 			goto bad;
273 #endif /* INET6 */
274 	} else {
275 		if ((m->m_pkthdr.csum_flags & M_UDP_CSUM_IN_OK) == 0) {
276 			if (m->m_pkthdr.csum_flags & M_UDP_CSUM_IN_BAD) {
277 				udpstat_inc(udps_badsum);
278 				goto bad;
279 			}
280 			udpstat_inc(udps_inswcsum);
281 
282 			if (ip)
283 				uh->uh_sum = in4_cksum(m, IPPROTO_UDP,
284 				    iphlen, len);
285 #ifdef INET6
286 			else if (ip6)
287 				uh->uh_sum = in6_cksum(m, IPPROTO_UDP,
288 				    iphlen, len);
289 #endif /* INET6 */
290 			if (uh->uh_sum != 0) {
291 				udpstat_inc(udps_badsum);
292 				goto bad;
293 			}
294 		}
295 	}
296 
297 #ifdef IPSEC
298 	if (udpencap_enable && udpencap_port && esp_enable &&
299 #if NPF > 0
300 	    !(m->m_pkthdr.pf.flags & PF_TAG_DIVERTED) &&
301 #endif
302 	    uh->uh_dport == htons(udpencap_port)) {
303 		u_int32_t spi;
304 		int skip = iphlen + sizeof(struct udphdr);
305 
306 		if (m->m_pkthdr.len - skip < sizeof(u_int32_t)) {
307 			/* packet too short */
308 			m_freem(m);
309 			return IPPROTO_DONE;
310 		}
311 		m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi);
312 		/*
313 		 * decapsulate if the SPI is not zero, otherwise pass
314 		 * to userland
315 		 */
316 		if (spi != 0) {
317 			int protoff;
318 
319 			if ((m = *mp = m_pullup(m, skip)) == NULL) {
320 				udpstat_inc(udps_hdrops);
321 				return IPPROTO_DONE;
322 			}
323 
324 			/* remove the UDP header */
325 			bcopy(mtod(m, u_char *),
326 			    mtod(m, u_char *) + sizeof(struct udphdr), iphlen);
327 			m_adj(m, sizeof(struct udphdr));
328 			skip -= sizeof(struct udphdr);
329 
330 			espstat_inc(esps_udpencin);
331 			protoff = af == AF_INET ? offsetof(struct ip, ip_p) :
332 			    offsetof(struct ip6_hdr, ip6_nxt);
333 			return ipsec_common_input(mp, skip, protoff,
334 			    af, IPPROTO_ESP, 1);
335 		}
336 	}
337 #endif /* IPSEC */
338 
339 	switch (af) {
340 	case AF_INET:
341 		bzero(&srcsa, sizeof(struct sockaddr_in));
342 		srcsa.sin.sin_len = sizeof(struct sockaddr_in);
343 		srcsa.sin.sin_family = AF_INET;
344 		srcsa.sin.sin_port = uh->uh_sport;
345 		srcsa.sin.sin_addr = ip->ip_src;
346 
347 		bzero(&dstsa, sizeof(struct sockaddr_in));
348 		dstsa.sin.sin_len = sizeof(struct sockaddr_in);
349 		dstsa.sin.sin_family = AF_INET;
350 		dstsa.sin.sin_port = uh->uh_dport;
351 		dstsa.sin.sin_addr = ip->ip_dst;
352 		break;
353 #ifdef INET6
354 	case AF_INET6:
355 		bzero(&srcsa, sizeof(struct sockaddr_in6));
356 		srcsa.sin6.sin6_len = sizeof(struct sockaddr_in6);
357 		srcsa.sin6.sin6_family = AF_INET6;
358 		srcsa.sin6.sin6_port = uh->uh_sport;
359 #if 0 /*XXX inbound flowinfo */
360 		srcsa.sin6.sin6_flowinfo = htonl(0x0fffffff) & ip6->ip6_flow;
361 #endif
362 		/* KAME hack: recover scopeid */
363 		in6_recoverscope(&srcsa.sin6, &ip6->ip6_src);
364 
365 		bzero(&dstsa, sizeof(struct sockaddr_in6));
366 		dstsa.sin6.sin6_len = sizeof(struct sockaddr_in6);
367 		dstsa.sin6.sin6_family = AF_INET6;
368 		dstsa.sin6.sin6_port = uh->uh_dport;
369 #if 0 /*XXX inbound flowinfo */
370 		dstsa.sin6.sin6_flowinfo = htonl(0x0fffffff) & ip6->ip6_flow;
371 #endif
372 		/* KAME hack: recover scopeid */
373 		in6_recoverscope(&dstsa.sin6, &ip6->ip6_dst);
374 		break;
375 #endif /* INET6 */
376 	}
377 
378 	if (m->m_flags & (M_BCAST|M_MCAST)) {
379 		SIMPLEQ_HEAD(, inpcb) inpcblist;
380 
381 		/*
382 		 * Deliver a multicast or broadcast datagram to *all* sockets
383 		 * for which the local and remote addresses and ports match
384 		 * those of the incoming datagram.  This allows more than
385 		 * one process to receive multi/broadcasts on the same port.
386 		 * (This really ought to be done for unicast datagrams as
387 		 * well, but that would cause problems with existing
388 		 * applications that open both address-specific sockets and
389 		 * a wildcard socket listening to the same port -- they would
390 		 * end up receiving duplicates of every unicast datagram.
391 		 * Those applications open the multiple sockets to overcome an
392 		 * inadequacy of the UDP socket interface, but for backwards
393 		 * compatibility we avoid the problem here rather than
394 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
395 		 */
396 
397 		/*
398 		 * Locate pcb(s) for datagram.
399 		 * (Algorithm copied from raw_intr().)
400 		 */
401 		SIMPLEQ_INIT(&inpcblist);
402 		rw_enter_write(&udbtable.inpt_notify);
403 		mtx_enter(&udbtable.inpt_mtx);
404 		TAILQ_FOREACH(inp, &udbtable.inpt_queue, inp_queue) {
405 			if (inp->inp_socket->so_state & SS_CANTRCVMORE)
406 				continue;
407 #ifdef INET6
408 			/* don't accept it if AF does not match */
409 			if (ip6 && !(inp->inp_flags & INP_IPV6))
410 				continue;
411 			if (!ip6 && (inp->inp_flags & INP_IPV6))
412 				continue;
413 #endif
414 			if (rtable_l2(inp->inp_rtableid) !=
415 			    rtable_l2(m->m_pkthdr.ph_rtableid))
416 				continue;
417 			if (inp->inp_lport != uh->uh_dport)
418 				continue;
419 #ifdef INET6
420 			if (ip6) {
421 				if (inp->inp_ip6_minhlim &&
422 				    inp->inp_ip6_minhlim > ip6->ip6_hlim)
423 					continue;
424 				if (!IN6_IS_ADDR_UNSPECIFIED(&inp->inp_laddr6))
425 					if (!IN6_ARE_ADDR_EQUAL(
426 					    &inp->inp_laddr6, &ip6->ip6_dst))
427 						continue;
428 			} else
429 #endif /* INET6 */
430 			{
431 				if (inp->inp_ip_minttl &&
432 				    inp->inp_ip_minttl > ip->ip_ttl)
433 					continue;
434 
435 				if (inp->inp_laddr.s_addr != INADDR_ANY) {
436 					if (inp->inp_laddr.s_addr !=
437 					    ip->ip_dst.s_addr)
438 						continue;
439 				}
440 			}
441 #ifdef INET6
442 			if (ip6) {
443 				if (!IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6))
444 					if (!IN6_ARE_ADDR_EQUAL(
445 					    &inp->inp_faddr6, &ip6->ip6_src) ||
446 					    inp->inp_fport != uh->uh_sport)
447 						continue;
448 			} else
449 #endif /* INET6 */
450 			if (inp->inp_faddr.s_addr != INADDR_ANY) {
451 				if (inp->inp_faddr.s_addr !=
452 				    ip->ip_src.s_addr ||
453 				    inp->inp_fport != uh->uh_sport)
454 					continue;
455 			}
456 
457 			in_pcbref(inp);
458 			SIMPLEQ_INSERT_TAIL(&inpcblist, inp, inp_notify);
459 
460 			/*
461 			 * Don't look for additional matches if this one does
462 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
463 			 * socket options set.  This heuristic avoids searching
464 			 * through all pcbs in the common case of a non-shared
465 			 * port.  It assumes that an application will never
466 			 * clear these options after setting them.
467 			 */
468 			if ((inp->inp_socket->so_options & (SO_REUSEPORT |
469 			    SO_REUSEADDR)) == 0)
470 				break;
471 		}
472 		mtx_leave(&udbtable.inpt_mtx);
473 
474 		if (SIMPLEQ_EMPTY(&inpcblist)) {
475 			rw_exit_write(&udbtable.inpt_notify);
476 
477 			/*
478 			 * No matching pcb found; discard datagram.
479 			 * (No need to send an ICMP Port Unreachable
480 			 * for a broadcast or multicast datgram.)
481 			 */
482 			udpstat_inc(udps_noportbcast);
483 			goto bad;
484 		}
485 
486 		while ((inp = SIMPLEQ_FIRST(&inpcblist)) != NULL) {
487 			struct mbuf *n;
488 
489 			SIMPLEQ_REMOVE_HEAD(&inpcblist, inp_notify);
490 			if (SIMPLEQ_EMPTY(&inpcblist))
491 				n = m;
492 			else
493 				n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
494 			if (n != NULL) {
495 				udp_sbappend(inp, n, ip, ip6, iphlen, uh,
496 				    &srcsa.sa, 0);
497 			}
498 			in_pcbunref(inp);
499 		}
500 		rw_exit_write(&udbtable.inpt_notify);
501 
502 		return IPPROTO_DONE;
503 	}
504 	/*
505 	 * Locate pcb for datagram.
506 	 */
507 #if NPF > 0
508 	inp = pf_inp_lookup(m);
509 #endif
510 	if (inp == NULL) {
511 #ifdef INET6
512 		if (ip6)
513 			inp = in6_pcblookup(&udbtable, &ip6->ip6_src,
514 			    uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
515 			    m->m_pkthdr.ph_rtableid);
516 		else
517 #endif /* INET6 */
518 		inp = in_pcblookup(&udbtable, ip->ip_src, uh->uh_sport,
519 		    ip->ip_dst, uh->uh_dport, m->m_pkthdr.ph_rtableid);
520 	}
521 	if (inp == NULL) {
522 		udpstat_inc(udps_pcbhashmiss);
523 #ifdef INET6
524 		if (ip6) {
525 			inp = in6_pcblookup_listen(&udbtable, &ip6->ip6_dst,
526 			    uh->uh_dport, m, m->m_pkthdr.ph_rtableid);
527 		} else
528 #endif /* INET6 */
529 		inp = in_pcblookup_listen(&udbtable, ip->ip_dst,
530 		    uh->uh_dport, m, m->m_pkthdr.ph_rtableid);
531 	}
532 
533 #ifdef IPSEC
534 	if (ipsec_in_use) {
535 		struct m_tag *mtag;
536 		struct tdb_ident *tdbi;
537 		struct tdb *tdb;
538 		int error;
539 
540 		mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
541 		if (mtag != NULL) {
542 			tdbi = (struct tdb_ident *)(mtag + 1);
543 			tdb = gettdb(tdbi->rdomain, tdbi->spi,
544 			    &tdbi->dst, tdbi->proto);
545 		} else
546 			tdb = NULL;
547 		error = ipsp_spd_lookup(m, af, iphlen, IPSP_DIRECTION_IN,
548 		    tdb, inp, NULL, NULL);
549 		if (error) {
550 			udpstat_inc(udps_nosec);
551 			tdb_unref(tdb);
552 			goto bad;
553 		}
554 		/* create ipsec options, id is not modified after creation */
555 		if (tdb && tdb->tdb_ids)
556 			ipsecflowinfo = tdb->tdb_ids->id_flow;
557 		tdb_unref(tdb);
558 	}
559 #endif /*IPSEC */
560 
561 	if (inp == NULL) {
562 		udpstat_inc(udps_noport);
563 		if (m->m_flags & (M_BCAST | M_MCAST)) {
564 			udpstat_inc(udps_noportbcast);
565 			goto bad;
566 		}
567 #ifdef INET6
568 		if (ip6) {
569 			uh->uh_sum = savesum;
570 			icmp6_error(m, ICMP6_DST_UNREACH,
571 			    ICMP6_DST_UNREACH_NOPORT,0);
572 		} else
573 #endif /* INET6 */
574 		{
575 			*ip = save_ip;
576 			uh->uh_sum = savesum;
577 			icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT,
578 			    0, 0);
579 		}
580 		return IPPROTO_DONE;
581 	}
582 
583 	KASSERT(sotoinpcb(inp->inp_socket) == inp);
584 	soassertlocked(inp->inp_socket);
585 
586 #ifdef INET6
587 	if (ip6 && inp->inp_ip6_minhlim &&
588 	    inp->inp_ip6_minhlim > ip6->ip6_hlim) {
589 		goto bad;
590 	} else
591 #endif
592 	if (ip && inp->inp_ip_minttl &&
593 	    inp->inp_ip_minttl > ip->ip_ttl) {
594 		goto bad;
595 	}
596 
597 #if NPF > 0
598 	if (inp->inp_socket->so_state & SS_ISCONNECTED)
599 		pf_inp_link(m, inp);
600 #endif
601 
602 #ifdef PIPEX
603 	if (pipex_enable && inp->inp_pipex) {
604 		struct pipex_session *session;
605 		int off = iphlen + sizeof(struct udphdr);
606 
607 		if ((session = pipex_l2tp_lookup_session(m, off)) != NULL) {
608 			m = *mp = pipex_l2tp_input(m, off, session,
609 			    ipsecflowinfo);
610 			pipex_rele_session(session);
611 			if (m == NULL) {
612 				in_pcbunref(inp);
613 				return IPPROTO_DONE;
614 			}
615 		}
616 	}
617 #endif
618 
619 	udp_sbappend(inp, m, ip, ip6, iphlen, uh, &srcsa.sa, ipsecflowinfo);
620 	in_pcbunref(inp);
621 	return IPPROTO_DONE;
622 bad:
623 	m_freem(m);
624 	in_pcbunref(inp);
625 	return IPPROTO_DONE;
626 }
627 
628 void
629 udp_sbappend(struct inpcb *inp, struct mbuf *m, struct ip *ip,
630     struct ip6_hdr *ip6, int hlen, struct udphdr *uh,
631     struct sockaddr *srcaddr, u_int32_t ipsecflowinfo)
632 {
633 	struct socket *so = inp->inp_socket;
634 	struct mbuf *opts = NULL;
635 
636 	hlen += sizeof(*uh);
637 
638 	if (inp->inp_upcall != NULL) {
639 		m = (*inp->inp_upcall)(inp->inp_upcall_arg, m,
640 		    ip, ip6, uh, hlen);
641 		if (m == NULL)
642 			return;
643 	}
644 
645 #ifdef INET6
646 	if (ip6 && (inp->inp_flags & IN6P_CONTROLOPTS ||
647 	    so->so_options & SO_TIMESTAMP))
648 		ip6_savecontrol(inp, m, &opts);
649 #endif /* INET6 */
650 	if (ip && (inp->inp_flags & INP_CONTROLOPTS ||
651 	    so->so_options & SO_TIMESTAMP))
652 		ip_savecontrol(inp, &opts, ip, m);
653 #ifdef INET6
654 	if (ip6 && (inp->inp_flags & IN6P_RECVDSTPORT)) {
655 		struct mbuf **mp = &opts;
656 
657 		while (*mp)
658 			mp = &(*mp)->m_next;
659 		*mp = sbcreatecontrol((caddr_t)&uh->uh_dport, sizeof(u_int16_t),
660 		    IPV6_RECVDSTPORT, IPPROTO_IPV6);
661 	}
662 #endif /* INET6 */
663 	if (ip && (inp->inp_flags & INP_RECVDSTPORT)) {
664 		struct mbuf **mp = &opts;
665 
666 		while (*mp)
667 			mp = &(*mp)->m_next;
668 		*mp = sbcreatecontrol((caddr_t)&uh->uh_dport, sizeof(u_int16_t),
669 		    IP_RECVDSTPORT, IPPROTO_IP);
670 	}
671 #ifdef IPSEC
672 	if (ipsecflowinfo && (inp->inp_flags & INP_IPSECFLOWINFO)) {
673 		struct mbuf **mp = &opts;
674 
675 		while (*mp)
676 			mp = &(*mp)->m_next;
677 		*mp = sbcreatecontrol((caddr_t)&ipsecflowinfo,
678 		    sizeof(u_int32_t), IP_IPSECFLOWINFO, IPPROTO_IP);
679 	}
680 #endif
681 	m_adj(m, hlen);
682 
683 	mtx_enter(&inp->inp_mtx);
684 	if (sbappendaddr(so, &so->so_rcv, srcaddr, m, opts) == 0) {
685 		mtx_leave(&inp->inp_mtx);
686 		udpstat_inc(udps_fullsock);
687 		m_freem(m);
688 		m_freem(opts);
689 		return;
690 	}
691 	mtx_leave(&inp->inp_mtx);
692 
693 	sorwakeup(so);
694 }
695 
696 /*
697  * Notify a udp user of an asynchronous error;
698  * just wake up so that he can collect error status.
699  */
700 void
701 udp_notify(struct inpcb *inp, int errno)
702 {
703 	inp->inp_socket->so_error = errno;
704 	sorwakeup(inp->inp_socket);
705 	sowwakeup(inp->inp_socket);
706 }
707 
708 #ifdef INET6
709 void
710 udp6_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *d)
711 {
712 	struct udphdr uh;
713 	struct sockaddr_in6 sa6;
714 	struct ip6_hdr *ip6;
715 	struct mbuf *m;
716 	int off;
717 	void *cmdarg;
718 	struct ip6ctlparam *ip6cp = NULL;
719 	struct udp_portonly {
720 		u_int16_t uh_sport;
721 		u_int16_t uh_dport;
722 	} *uhp;
723 	struct inpcb *inp;
724 	void (*notify)(struct inpcb *, int) = udp_notify;
725 
726 	if (sa == NULL)
727 		return;
728 	if (sa->sa_family != AF_INET6 ||
729 	    sa->sa_len != sizeof(struct sockaddr_in6))
730 		return;
731 
732 	if ((unsigned)cmd >= PRC_NCMDS)
733 		return;
734 	if (PRC_IS_REDIRECT(cmd))
735 		notify = in_rtchange, d = NULL;
736 	else if (cmd == PRC_HOSTDEAD)
737 		d = NULL;
738 	else if (cmd == PRC_MSGSIZE)
739 		; /* special code is present, see below */
740 	else if (inet6ctlerrmap[cmd] == 0)
741 		return;
742 
743 	/* if the parameter is from icmp6, decode it. */
744 	if (d != NULL) {
745 		ip6cp = (struct ip6ctlparam *)d;
746 		m = ip6cp->ip6c_m;
747 		ip6 = ip6cp->ip6c_ip6;
748 		off = ip6cp->ip6c_off;
749 		cmdarg = ip6cp->ip6c_cmdarg;
750 	} else {
751 		m = NULL;
752 		ip6 = NULL;
753 		cmdarg = NULL;
754 		/* XXX: translate addresses into internal form */
755 		sa6 = *satosin6(sa);
756 		if (in6_embedscope(&sa6.sin6_addr, &sa6, NULL)) {
757 			/* should be impossible */
758 			return;
759 		}
760 	}
761 
762 	if (ip6cp && ip6cp->ip6c_finaldst) {
763 		bzero(&sa6, sizeof(sa6));
764 		sa6.sin6_family = AF_INET6;
765 		sa6.sin6_len = sizeof(sa6);
766 		sa6.sin6_addr = *ip6cp->ip6c_finaldst;
767 		/* XXX: assuming M is valid in this case */
768 		sa6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.ph_ifidx,
769 		    ip6cp->ip6c_finaldst);
770 		if (in6_embedscope(ip6cp->ip6c_finaldst, &sa6, NULL)) {
771 			/* should be impossible */
772 			return;
773 		}
774 	} else {
775 		/* XXX: translate addresses into internal form */
776 		sa6 = *satosin6(sa);
777 		if (in6_embedscope(&sa6.sin6_addr, &sa6, NULL)) {
778 			/* should be impossible */
779 			return;
780 		}
781 	}
782 
783 	if (ip6) {
784 		/*
785 		 * XXX: We assume that when IPV6 is non NULL,
786 		 * M and OFF are valid.
787 		 */
788 		struct sockaddr_in6 sa6_src;
789 
790 		/* check if we can safely examine src and dst ports */
791 		if (m->m_pkthdr.len < off + sizeof(*uhp))
792 			return;
793 
794 		bzero(&uh, sizeof(uh));
795 		m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
796 
797 		bzero(&sa6_src, sizeof(sa6_src));
798 		sa6_src.sin6_family = AF_INET6;
799 		sa6_src.sin6_len = sizeof(sa6_src);
800 		sa6_src.sin6_addr = ip6->ip6_src;
801 		sa6_src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.ph_ifidx,
802 		    &ip6->ip6_src);
803 		if (in6_embedscope(&sa6_src.sin6_addr, &sa6_src, NULL)) {
804 			/* should be impossible */
805 			return;
806 		}
807 
808 		if (cmd == PRC_MSGSIZE) {
809 			/*
810 			 * Check to see if we have a valid UDP socket
811 			 * corresponding to the address in the ICMPv6 message
812 			 * payload.
813 			 */
814 			inp = in6_pcblookup(&udbtable, &sa6.sin6_addr,
815 			    uh.uh_dport, &sa6_src.sin6_addr, uh.uh_sport,
816 			    rdomain);
817 #if 0
818 			/*
819 			 * As the use of sendto(2) is fairly popular,
820 			 * we may want to allow non-connected pcb too.
821 			 * But it could be too weak against attacks...
822 			 * We should at least check if the local address (= s)
823 			 * is really ours.
824 			 */
825 			if (inp == NULL) {
826 				inp = in6_pcblookup_listen(&udbtable,
827 				    &sa6_src.sin6_addr, uh.uh_sport, NULL,
828 				    rdomain))
829 			}
830 #endif
831 
832 			/*
833 			 * Depending on the value of "valid" and routing table
834 			 * size (mtudisc_{hi,lo}wat), we will:
835 			 * - recalculate the new MTU and create the
836 			 *   corresponding routing entry, or
837 			 * - ignore the MTU change notification.
838 			 */
839 			icmp6_mtudisc_update((struct ip6ctlparam *)d,
840 			    inp != NULL);
841 			in_pcbunref(inp);
842 
843 			/*
844 			 * regardless of if we called icmp6_mtudisc_update(),
845 			 * we need to call in6_pcbnotify(), to notify path
846 			 * MTU change to the userland (2292bis-02), because
847 			 * some unconnected sockets may share the same
848 			 * destination and want to know the path MTU.
849 			 */
850 		}
851 
852 		in6_pcbnotify(&udbtable, &sa6, uh.uh_dport,
853 		    &sa6_src, uh.uh_sport, rdomain, cmd, cmdarg, notify);
854 	} else {
855 		in6_pcbnotify(&udbtable, &sa6, 0,
856 		    &sa6_any, 0, rdomain, cmd, cmdarg, notify);
857 	}
858 }
859 #endif
860 
861 void
862 udp_ctlinput(int cmd, struct sockaddr *sa, u_int rdomain, void *v)
863 {
864 	struct ip *ip = v;
865 	struct udphdr *uhp;
866 	struct in_addr faddr;
867 	struct inpcb *inp;
868 	void (*notify)(struct inpcb *, int) = udp_notify;
869 	int errno;
870 
871 	if (sa == NULL)
872 		return;
873 	if (sa->sa_family != AF_INET ||
874 	    sa->sa_len != sizeof(struct sockaddr_in))
875 		return;
876 	faddr = satosin(sa)->sin_addr;
877 	if (faddr.s_addr == INADDR_ANY)
878 		return;
879 
880 	if ((unsigned)cmd >= PRC_NCMDS)
881 		return;
882 	errno = inetctlerrmap[cmd];
883 	if (PRC_IS_REDIRECT(cmd))
884 		notify = in_rtchange, ip = 0;
885 	else if (cmd == PRC_HOSTDEAD)
886 		ip = 0;
887 	else if (errno == 0)
888 		return;
889 	if (ip) {
890 		uhp = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
891 
892 #ifdef IPSEC
893 		/* PMTU discovery for udpencap */
894 		if (cmd == PRC_MSGSIZE && ip_mtudisc && udpencap_enable &&
895 		    udpencap_port && uhp->uh_sport == htons(udpencap_port)) {
896 			udpencap_ctlinput(cmd, sa, rdomain, v);
897 			return;
898 		}
899 #endif
900 		inp = in_pcblookup(&udbtable,
901 		    ip->ip_dst, uhp->uh_dport, ip->ip_src, uhp->uh_sport,
902 		    rdomain);
903 		if (inp && inp->inp_socket != NULL)
904 			notify(inp, errno);
905 		in_pcbunref(inp);
906 	} else
907 		in_pcbnotifyall(&udbtable, sa, rdomain, errno, notify);
908 }
909 
910 int
911 udp_output(struct inpcb *inp, struct mbuf *m, struct mbuf *addr,
912     struct mbuf *control)
913 {
914 	struct sockaddr_in *sin = NULL;
915 	struct udpiphdr *ui;
916 	u_int32_t ipsecflowinfo = 0;
917 	struct sockaddr_in src_sin;
918 	int len = m->m_pkthdr.len;
919 	struct in_addr laddr;
920 	int error = 0;
921 
922 #ifdef DIAGNOSTIC
923 	if ((inp->inp_flags & INP_IPV6) != 0)
924 		panic("IPv6 inpcb to %s", __func__);
925 #endif
926 
927 	/*
928 	 * Compute the packet length of the IP header, and
929 	 * punt if the length looks bogus.
930 	 */
931 	if ((len + sizeof(struct udpiphdr)) > IP_MAXPACKET) {
932 		error = EMSGSIZE;
933 		goto release;
934 	}
935 
936 	memset(&src_sin, 0, sizeof(src_sin));
937 
938 	if (control) {
939 		u_int clen;
940 		struct cmsghdr *cm;
941 		caddr_t cmsgs;
942 
943 		/*
944 		 * XXX: Currently, we assume all the optional information is
945 		 * stored in a single mbuf.
946 		 */
947 		if (control->m_next) {
948 			error = EINVAL;
949 			goto release;
950 		}
951 
952 		clen = control->m_len;
953 		cmsgs = mtod(control, caddr_t);
954 		do {
955 			if (clen < CMSG_LEN(0)) {
956 				error = EINVAL;
957 				goto release;
958 			}
959 			cm = (struct cmsghdr *)cmsgs;
960 			if (cm->cmsg_len < CMSG_LEN(0) ||
961 			    CMSG_ALIGN(cm->cmsg_len) > clen) {
962 				error = EINVAL;
963 				goto release;
964 			}
965 #ifdef IPSEC
966 			if ((inp->inp_flags & INP_IPSECFLOWINFO) != 0 &&
967 			    cm->cmsg_len == CMSG_LEN(sizeof(ipsecflowinfo)) &&
968 			    cm->cmsg_level == IPPROTO_IP &&
969 			    cm->cmsg_type == IP_IPSECFLOWINFO) {
970 				ipsecflowinfo = *(u_int32_t *)CMSG_DATA(cm);
971 			} else
972 #endif
973 			if (cm->cmsg_len == CMSG_LEN(sizeof(struct in_addr)) &&
974 			    cm->cmsg_level == IPPROTO_IP &&
975 			    cm->cmsg_type == IP_SENDSRCADDR) {
976 				memcpy(&src_sin.sin_addr, CMSG_DATA(cm),
977 				    sizeof(struct in_addr));
978 				src_sin.sin_family = AF_INET;
979 				src_sin.sin_len = sizeof(src_sin);
980 				/* no check on reuse when sin->sin_port == 0 */
981 				if ((error = in_pcbaddrisavail(inp, &src_sin,
982 				    0, curproc)))
983 					goto release;
984 			}
985 			clen -= CMSG_ALIGN(cm->cmsg_len);
986 			cmsgs += CMSG_ALIGN(cm->cmsg_len);
987 		} while (clen);
988 	}
989 
990 	if (addr) {
991 		if ((error = in_nam2sin(addr, &sin)))
992 			goto release;
993 		if (sin->sin_port == 0) {
994 			error = EADDRNOTAVAIL;
995 			goto release;
996 		}
997 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
998 			error = EISCONN;
999 			goto release;
1000 		}
1001 		error = in_pcbselsrc(&laddr, sin, inp);
1002 		if (error)
1003 			goto release;
1004 
1005 		if (inp->inp_lport == 0) {
1006 			error = in_pcbbind(inp, NULL, curproc);
1007 			if (error)
1008 				goto release;
1009 		}
1010 
1011 		if (src_sin.sin_len > 0 &&
1012 		    src_sin.sin_addr.s_addr != INADDR_ANY &&
1013 		    src_sin.sin_addr.s_addr != inp->inp_laddr.s_addr) {
1014 			src_sin.sin_port = inp->inp_lport;
1015 			if (inp->inp_laddr.s_addr != INADDR_ANY &&
1016 			    (error =
1017 			    in_pcbaddrisavail(inp, &src_sin, 0, curproc)))
1018 				goto release;
1019 			laddr = src_sin.sin_addr;
1020 		}
1021 	} else {
1022 		if (inp->inp_faddr.s_addr == INADDR_ANY) {
1023 			error = ENOTCONN;
1024 			goto release;
1025 		}
1026 		laddr = inp->inp_laddr;
1027 	}
1028 
1029 	/*
1030 	 * Calculate data length and get a mbuf
1031 	 * for UDP and IP headers.
1032 	 */
1033 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
1034 	if (m == NULL) {
1035 		error = ENOBUFS;
1036 		goto bail;
1037 	}
1038 
1039 	/*
1040 	 * Fill in mbuf with extended UDP header
1041 	 * and addresses and length put into network format.
1042 	 */
1043 	ui = mtod(m, struct udpiphdr *);
1044 	bzero(ui->ui_x1, sizeof ui->ui_x1);
1045 	ui->ui_pr = IPPROTO_UDP;
1046 	ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr));
1047 	ui->ui_src = laddr;
1048 	ui->ui_dst = sin ? sin->sin_addr : inp->inp_faddr;
1049 	ui->ui_sport = inp->inp_lport;
1050 	ui->ui_dport = sin ? sin->sin_port : inp->inp_fport;
1051 	ui->ui_ulen = ui->ui_len;
1052 	((struct ip *)ui)->ip_len = htons(sizeof (struct udpiphdr) + len);
1053 	((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;
1054 	((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;
1055 	if (udpcksum)
1056 		m->m_pkthdr.csum_flags |= M_UDP_CSUM_OUT;
1057 
1058 	udpstat_inc(udps_opackets);
1059 
1060 	/* force routing table */
1061 	m->m_pkthdr.ph_rtableid = inp->inp_rtableid;
1062 
1063 #if NPF > 0
1064 	if (inp->inp_socket->so_state & SS_ISCONNECTED)
1065 		pf_mbuf_link_inpcb(m, inp);
1066 #endif
1067 
1068 	error = ip_output(m, inp->inp_options, &inp->inp_route,
1069 	    (inp->inp_socket->so_options & SO_BROADCAST), inp->inp_moptions,
1070 	    inp, ipsecflowinfo);
1071 
1072 bail:
1073 	m_freem(control);
1074 	return (error);
1075 
1076 release:
1077 	m_freem(m);
1078 	goto bail;
1079 }
1080 
1081 int
1082 udp_attach(struct socket *so, int proto)
1083 {
1084 	int error;
1085 
1086 	if (so->so_pcb != NULL)
1087 		return EINVAL;
1088 
1089 	if ((error = soreserve(so, udp_sendspace, udp_recvspace)))
1090 		return error;
1091 
1092 	NET_ASSERT_LOCKED();
1093 	if ((error = in_pcballoc(so, &udbtable)))
1094 		return error;
1095 #ifdef INET6
1096 	if (sotoinpcb(so)->inp_flags & INP_IPV6)
1097 		sotoinpcb(so)->inp_ipv6.ip6_hlim = ip6_defhlim;
1098 	else
1099 #endif /* INET6 */
1100 		sotoinpcb(so)->inp_ip.ip_ttl = ip_defttl;
1101 	return 0;
1102 }
1103 
1104 int
1105 udp_detach(struct socket *so)
1106 {
1107 	struct inpcb *inp;
1108 
1109 	soassertlocked(so);
1110 
1111 	inp = sotoinpcb(so);
1112 	if (inp == NULL)
1113 		return (EINVAL);
1114 
1115 	in_pcbdetach(inp);
1116 	return (0);
1117 }
1118 
1119 void
1120 udp_lock(struct socket *so)
1121 {
1122 	struct inpcb *inp = sotoinpcb(so);
1123 
1124 	NET_ASSERT_LOCKED();
1125 	mtx_enter(&inp->inp_mtx);
1126 }
1127 
1128 void
1129 udp_unlock(struct socket *so)
1130 {
1131 	struct inpcb *inp = sotoinpcb(so);
1132 
1133 	NET_ASSERT_LOCKED();
1134 	mtx_leave(&inp->inp_mtx);
1135 }
1136 
1137 int
1138 udp_bind(struct socket *so, struct mbuf *addr, struct proc *p)
1139 {
1140 	struct inpcb *inp = sotoinpcb(so);
1141 
1142 	soassertlocked(so);
1143 	return in_pcbbind(inp, addr, p);
1144 }
1145 
1146 int
1147 udp_connect(struct socket *so, struct mbuf *addr)
1148 {
1149 	struct inpcb *inp = sotoinpcb(so);
1150 	int error;
1151 
1152 	soassertlocked(so);
1153 
1154 #ifdef INET6
1155 	if (inp->inp_flags & INP_IPV6) {
1156 		if (!IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6))
1157 			return (EISCONN);
1158 		error = in6_pcbconnect(inp, addr);
1159 	} else
1160 #endif /* INET6 */
1161 	{
1162 		if (inp->inp_faddr.s_addr != INADDR_ANY)
1163 			return (EISCONN);
1164 		error = in_pcbconnect(inp, addr);
1165 	}
1166 
1167 	if (error)
1168 		return (error);
1169 
1170 	soisconnected(so);
1171 	return (0);
1172 }
1173 
1174 int
1175 udp_disconnect(struct socket *so)
1176 {
1177 	struct inpcb *inp = sotoinpcb(so);
1178 
1179 	soassertlocked(so);
1180 
1181 #ifdef INET6
1182 	if (inp->inp_flags & INP_IPV6) {
1183 		if (IN6_IS_ADDR_UNSPECIFIED(&inp->inp_faddr6))
1184 			return (ENOTCONN);
1185 	} else
1186 #endif /* INET6 */
1187 	{
1188 		if (inp->inp_faddr.s_addr == INADDR_ANY)
1189 			return (ENOTCONN);
1190 	}
1191 
1192 #ifdef INET6
1193 	if (inp->inp_flags & INP_IPV6)
1194 		inp->inp_laddr6 = in6addr_any;
1195 	else
1196 #endif /* INET6 */
1197 		inp->inp_laddr.s_addr = INADDR_ANY;
1198 
1199 	in_pcbdisconnect(inp);
1200 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
1201 
1202 	return (0);
1203 }
1204 
1205 int
1206 udp_shutdown(struct socket *so)
1207 {
1208 	soassertlocked(so);
1209 	socantsendmore(so);
1210 	return (0);
1211 }
1212 
1213 int
1214 udp_send(struct socket *so, struct mbuf *m, struct mbuf *addr,
1215     struct mbuf *control)
1216 {
1217 	struct inpcb *inp = sotoinpcb(so);
1218 	int error;
1219 
1220 	soassertlocked(so);
1221 
1222 #ifdef PIPEX
1223 	if (inp->inp_pipex) {
1224 		struct pipex_session *session;
1225 
1226 		if (addr != NULL)
1227 			session =
1228 			    pipex_l2tp_userland_lookup_session(m,
1229 				mtod(addr, struct sockaddr *));
1230 		else
1231 #ifdef INET6
1232 		if (inp->inp_flags & INP_IPV6)
1233 			session =
1234 			    pipex_l2tp_userland_lookup_session_ipv6(
1235 				m, inp->inp_faddr6);
1236 		else
1237 #endif
1238 			session =
1239 			    pipex_l2tp_userland_lookup_session_ipv4(
1240 				m, inp->inp_faddr);
1241 		if (session != NULL) {
1242 			m = pipex_l2tp_userland_output(m, session);
1243 			pipex_rele_session(session);
1244 
1245 			if (m == NULL) {
1246 				m_freem(control);
1247 				return (ENOMEM);
1248 			}
1249 		}
1250 	}
1251 #endif
1252 
1253 #ifdef INET6
1254 	if (inp->inp_flags & INP_IPV6)
1255 		error = udp6_output(inp, m, addr, control);
1256 	else
1257 #endif
1258 		error = udp_output(inp, m, addr, control);
1259 
1260 	return (error);
1261 }
1262 
1263 int
1264 udp_abort(struct socket *so)
1265 {
1266 	struct inpcb *inp = sotoinpcb(so);
1267 
1268 	soassertlocked(so);
1269 
1270 	soisdisconnected(so);
1271 	in_pcbdetach(inp);
1272 
1273 	return (0);
1274 }
1275 
1276 /*
1277  * Sysctl for udp variables.
1278  */
1279 int
1280 udp_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
1281     size_t newlen)
1282 {
1283 	int error;
1284 
1285 	/* All sysctl names at this level are terminal. */
1286 	if (namelen != 1)
1287 		return (ENOTDIR);
1288 
1289 	switch (name[0]) {
1290 	case UDPCTL_BADDYNAMIC:
1291 		NET_LOCK();
1292 		error = sysctl_struct(oldp, oldlenp, newp, newlen,
1293 		    baddynamicports.udp, sizeof(baddynamicports.udp));
1294 		NET_UNLOCK();
1295 		return (error);
1296 
1297 	case UDPCTL_ROOTONLY:
1298 		if (newp && securelevel > 0)
1299 			return (EPERM);
1300 		NET_LOCK();
1301 		error = sysctl_struct(oldp, oldlenp, newp, newlen,
1302 		    rootonlyports.udp, sizeof(rootonlyports.udp));
1303 		NET_UNLOCK();
1304 		return (error);
1305 
1306 	case UDPCTL_STATS:
1307 		if (newp != NULL)
1308 			return (EPERM);
1309 
1310 		return (udp_sysctl_udpstat(oldp, oldlenp, newp));
1311 
1312 	default:
1313 		NET_LOCK();
1314 		error = sysctl_bounded_arr(udpctl_vars, nitems(udpctl_vars),
1315 		    name, namelen, oldp, oldlenp, newp, newlen);
1316 		NET_UNLOCK();
1317 		return (error);
1318 	}
1319 	/* NOTREACHED */
1320 }
1321 
1322 int
1323 udp_sysctl_udpstat(void *oldp, size_t *oldlenp, void *newp)
1324 {
1325 	uint64_t counters[udps_ncounters];
1326 	struct udpstat udpstat;
1327 	u_long *words = (u_long *)&udpstat;
1328 	int i;
1329 
1330 	CTASSERT(sizeof(udpstat) == (nitems(counters) * sizeof(u_long)));
1331 	memset(&udpstat, 0, sizeof udpstat);
1332 	counters_read(udpcounters, counters, nitems(counters));
1333 
1334 	for (i = 0; i < nitems(counters); i++)
1335 		words[i] = (u_long)counters[i];
1336 
1337 	return (sysctl_rdstruct(oldp, oldlenp, newp,
1338 	    &udpstat, sizeof(udpstat)));
1339 }
1340