xref: /netbsd-src/sys/netinet/udp_usrreq.c (revision 6cd39ddb8550f6fa1bff3fed32053d7f19fd0453)
1 /*	$NetBSD: udp_usrreq.c,v 1.223 2016/01/20 22:01:18 riastradh Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
61  */
62 
63 /*
64  * UDP protocol implementation.
65  * Per RFC 768, August, 1980.
66  */
67 
68 #include <sys/cdefs.h>
69 __KERNEL_RCSID(0, "$NetBSD: udp_usrreq.c,v 1.223 2016/01/20 22:01:18 riastradh Exp $");
70 
71 #ifdef _KERNEL_OPT
72 #include "opt_inet.h"
73 #include "opt_compat_netbsd.h"
74 #include "opt_ipsec.h"
75 #include "opt_inet_csum.h"
76 #include "opt_ipkdb.h"
77 #include "opt_mbuftrace.h"
78 #endif
79 
80 #include <sys/param.h>
81 #include <sys/mbuf.h>
82 #include <sys/once.h>
83 #include <sys/protosw.h>
84 #include <sys/socket.h>
85 #include <sys/socketvar.h>
86 #include <sys/systm.h>
87 #include <sys/proc.h>
88 #include <sys/domain.h>
89 #include <sys/sysctl.h>
90 
91 #include <net/if.h>
92 #include <net/route.h>
93 
94 #include <netinet/in.h>
95 #include <netinet/in_systm.h>
96 #include <netinet/in_var.h>
97 #include <netinet/ip.h>
98 #include <netinet/in_pcb.h>
99 #include <netinet/ip_var.h>
100 #include <netinet/ip_icmp.h>
101 #include <netinet/udp.h>
102 #include <netinet/udp_var.h>
103 #include <netinet/udp_private.h>
104 
105 #ifdef INET6
106 #include <netinet/ip6.h>
107 #include <netinet/icmp6.h>
108 #include <netinet6/ip6_var.h>
109 #include <netinet6/ip6_private.h>
110 #include <netinet6/in6_pcb.h>
111 #include <netinet6/udp6_var.h>
112 #include <netinet6/udp6_private.h>
113 #endif
114 
115 #ifndef INET6
116 /* always need ip6.h for IP6_EXTHDR_GET */
117 #include <netinet/ip6.h>
118 #endif
119 
120 #ifdef IPSEC
121 #include <netipsec/ipsec.h>
122 #include <netipsec/ipsec_var.h>
123 #include <netipsec/ipsec_private.h>
124 #include <netipsec/esp.h>
125 #ifdef INET6
126 #include <netipsec/ipsec6.h>
127 #endif
128 #endif	/* IPSEC */
129 
130 #ifdef COMPAT_50
131 #include <compat/sys/socket.h>
132 #endif
133 
134 #ifdef IPKDB
135 #include <ipkdb/ipkdb.h>
136 #endif
137 
138 int	udpcksum = 1;
139 int	udp_do_loopback_cksum = 0;
140 
141 struct	inpcbtable udbtable;
142 
143 percpu_t *udpstat_percpu;
144 
145 #ifdef INET
146 #ifdef IPSEC
147 static int udp4_espinudp (struct mbuf **, int, struct sockaddr *,
148 	struct socket *);
149 #endif
150 static void udp4_sendup (struct mbuf *, int, struct sockaddr *,
151 	struct socket *);
152 static int udp4_realinput (struct sockaddr_in *, struct sockaddr_in *,
153 	struct mbuf **, int);
154 static int udp4_input_checksum(struct mbuf *, const struct udphdr *, int, int);
155 #endif
156 #ifdef INET
157 static	void udp_notify (struct inpcb *, int);
158 #endif
159 
160 #ifndef UDBHASHSIZE
161 #define	UDBHASHSIZE	128
162 #endif
163 int	udbhashsize = UDBHASHSIZE;
164 
165 /*
166  * For send - really max datagram size; for receive - 40 1K datagrams.
167  */
168 static int	udp_sendspace = 9216;
169 static int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
170 
171 #ifdef MBUFTRACE
172 struct mowner udp_mowner = MOWNER_INIT("udp", "");
173 struct mowner udp_rx_mowner = MOWNER_INIT("udp", "rx");
174 struct mowner udp_tx_mowner = MOWNER_INIT("udp", "tx");
175 #endif
176 
177 #ifdef UDP_CSUM_COUNTERS
178 #include <sys/device.h>
179 
180 #if defined(INET)
181 struct evcnt udp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
182     NULL, "udp", "hwcsum bad");
183 struct evcnt udp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
184     NULL, "udp", "hwcsum ok");
185 struct evcnt udp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
186     NULL, "udp", "hwcsum data");
187 struct evcnt udp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
188     NULL, "udp", "swcsum");
189 
190 EVCNT_ATTACH_STATIC(udp_hwcsum_bad);
191 EVCNT_ATTACH_STATIC(udp_hwcsum_ok);
192 EVCNT_ATTACH_STATIC(udp_hwcsum_data);
193 EVCNT_ATTACH_STATIC(udp_swcsum);
194 #endif /* defined(INET) */
195 
196 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
197 #else
198 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
199 #endif /* UDP_CSUM_COUNTERS */
200 
201 static void sysctl_net_inet_udp_setup(struct sysctllog **);
202 
203 static int
204 do_udpinit(void)
205 {
206 
207 	in_pcbinit(&udbtable, udbhashsize, udbhashsize);
208 	udpstat_percpu = percpu_alloc(sizeof(uint64_t) * UDP_NSTATS);
209 
210 	MOWNER_ATTACH(&udp_tx_mowner);
211 	MOWNER_ATTACH(&udp_rx_mowner);
212 	MOWNER_ATTACH(&udp_mowner);
213 
214 	return 0;
215 }
216 
217 void
218 udp_init_common(void)
219 {
220 	static ONCE_DECL(doudpinit);
221 
222 	RUN_ONCE(&doudpinit, do_udpinit);
223 }
224 
225 void
226 udp_init(void)
227 {
228 
229 	sysctl_net_inet_udp_setup(NULL);
230 
231 	udp_init_common();
232 }
233 
234 /*
235  * Checksum extended UDP header and data.
236  */
237 
238 int
239 udp_input_checksum(int af, struct mbuf *m, const struct udphdr *uh,
240     int iphlen, int len)
241 {
242 
243 	switch (af) {
244 #ifdef INET
245 	case AF_INET:
246 		return udp4_input_checksum(m, uh, iphlen, len);
247 #endif
248 #ifdef INET6
249 	case AF_INET6:
250 		return udp6_input_checksum(m, uh, iphlen, len);
251 #endif
252 	}
253 #ifdef DIAGNOSTIC
254 	panic("udp_input_checksum: unknown af %d", af);
255 #endif
256 	/* NOTREACHED */
257 	return -1;
258 }
259 
260 #ifdef INET
261 
262 /*
263  * Checksum extended UDP header and data.
264  */
265 
266 static int
267 udp4_input_checksum(struct mbuf *m, const struct udphdr *uh,
268     int iphlen, int len)
269 {
270 
271 	/*
272 	 * XXX it's better to record and check if this mbuf is
273 	 * already checked.
274 	 */
275 
276 	if (uh->uh_sum == 0)
277 		return 0;
278 
279 	switch (m->m_pkthdr.csum_flags &
280 	    ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_UDPv4) |
281 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
282 	case M_CSUM_UDPv4|M_CSUM_TCP_UDP_BAD:
283 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_bad);
284 		goto badcsum;
285 
286 	case M_CSUM_UDPv4|M_CSUM_DATA: {
287 		u_int32_t hw_csum = m->m_pkthdr.csum_data;
288 
289 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_data);
290 		if (m->m_pkthdr.csum_flags & M_CSUM_NO_PSEUDOHDR) {
291 			const struct ip *ip =
292 			    mtod(m, const struct ip *);
293 
294 			hw_csum = in_cksum_phdr(ip->ip_src.s_addr,
295 			    ip->ip_dst.s_addr,
296 			    htons(hw_csum + len + IPPROTO_UDP));
297 		}
298 		if ((hw_csum ^ 0xffff) != 0)
299 			goto badcsum;
300 		break;
301 	}
302 
303 	case M_CSUM_UDPv4:
304 		/* Checksum was okay. */
305 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_ok);
306 		break;
307 
308 	default:
309 		/*
310 		 * Need to compute it ourselves.  Maybe skip checksum
311 		 * on loopback interfaces.
312 		 */
313 		if (__predict_true(!(m->m_pkthdr.rcvif->if_flags &
314 				     IFF_LOOPBACK) ||
315 				   udp_do_loopback_cksum)) {
316 			UDP_CSUM_COUNTER_INCR(&udp_swcsum);
317 			if (in4_cksum(m, IPPROTO_UDP, iphlen, len) != 0)
318 				goto badcsum;
319 		}
320 		break;
321 	}
322 
323 	return 0;
324 
325 badcsum:
326 	UDP_STATINC(UDP_STAT_BADSUM);
327 	return -1;
328 }
329 
330 void
331 udp_input(struct mbuf *m, ...)
332 {
333 	va_list ap;
334 	struct sockaddr_in src, dst;
335 	struct ip *ip;
336 	struct udphdr *uh;
337 	int iphlen;
338 	int len;
339 	int n;
340 	u_int16_t ip_len;
341 
342 	va_start(ap, m);
343 	iphlen = va_arg(ap, int);
344 	(void)va_arg(ap, int);		/* ignore value, advance ap */
345 	va_end(ap);
346 
347 	MCLAIM(m, &udp_rx_mowner);
348 	UDP_STATINC(UDP_STAT_IPACKETS);
349 
350 	/*
351 	 * Get IP and UDP header together in first mbuf.
352 	 */
353 	ip = mtod(m, struct ip *);
354 	IP6_EXTHDR_GET(uh, struct udphdr *, m, iphlen, sizeof(struct udphdr));
355 	if (uh == NULL) {
356 		UDP_STATINC(UDP_STAT_HDROPS);
357 		return;
358 	}
359 	KASSERT(UDP_HDR_ALIGNED_P(uh));
360 
361 	/* destination port of 0 is illegal, based on RFC768. */
362 	if (uh->uh_dport == 0)
363 		goto bad;
364 
365 	/*
366 	 * Make mbuf data length reflect UDP length.
367 	 * If not enough data to reflect UDP length, drop.
368 	 */
369 	ip_len = ntohs(ip->ip_len);
370 	len = ntohs((u_int16_t)uh->uh_ulen);
371 	if (ip_len != iphlen + len) {
372 		if (ip_len < iphlen + len || len < sizeof(struct udphdr)) {
373 			UDP_STATINC(UDP_STAT_BADLEN);
374 			goto bad;
375 		}
376 		m_adj(m, iphlen + len - ip_len);
377 	}
378 
379 	/*
380 	 * Checksum extended UDP header and data.
381 	 */
382 	if (udp4_input_checksum(m, uh, iphlen, len))
383 		goto badcsum;
384 
385 	/* construct source and dst sockaddrs. */
386 	sockaddr_in_init(&src, &ip->ip_src, uh->uh_sport);
387 	sockaddr_in_init(&dst, &ip->ip_dst, uh->uh_dport);
388 
389 	if ((n = udp4_realinput(&src, &dst, &m, iphlen)) == -1) {
390 		UDP_STATINC(UDP_STAT_HDROPS);
391 		return;
392 	}
393 	if (m == NULL) {
394 		/*
395 		 * packet has been processed by ESP stuff -
396 		 * e.g. dropped NAT-T-keep-alive-packet ...
397 		 */
398 		return;
399 	}
400 	ip = mtod(m, struct ip *);
401 #ifdef INET6
402 	if (IN_MULTICAST(ip->ip_dst.s_addr) || n == 0) {
403 		struct sockaddr_in6 src6, dst6;
404 
405 		memset(&src6, 0, sizeof(src6));
406 		src6.sin6_family = AF_INET6;
407 		src6.sin6_len = sizeof(struct sockaddr_in6);
408 		src6.sin6_addr.s6_addr[10] = src6.sin6_addr.s6_addr[11] = 0xff;
409 		memcpy(&src6.sin6_addr.s6_addr[12], &ip->ip_src,
410 			sizeof(ip->ip_src));
411 		src6.sin6_port = uh->uh_sport;
412 		memset(&dst6, 0, sizeof(dst6));
413 		dst6.sin6_family = AF_INET6;
414 		dst6.sin6_len = sizeof(struct sockaddr_in6);
415 		dst6.sin6_addr.s6_addr[10] = dst6.sin6_addr.s6_addr[11] = 0xff;
416 		memcpy(&dst6.sin6_addr.s6_addr[12], &ip->ip_dst,
417 			sizeof(ip->ip_dst));
418 		dst6.sin6_port = uh->uh_dport;
419 
420 		n += udp6_realinput(AF_INET, &src6, &dst6, m, iphlen);
421 	}
422 #endif
423 
424 	if (n == 0) {
425 		if (m->m_flags & (M_BCAST | M_MCAST)) {
426 			UDP_STATINC(UDP_STAT_NOPORTBCAST);
427 			goto bad;
428 		}
429 		UDP_STATINC(UDP_STAT_NOPORT);
430 #ifdef IPKDB
431 		if (checkipkdb(&ip->ip_src, uh->uh_sport, uh->uh_dport,
432 				m, iphlen + sizeof(struct udphdr),
433 				m->m_pkthdr.len - iphlen - sizeof(struct udphdr))) {
434 			/*
435 			 * It was a debugger connect packet,
436 			 * just drop it now
437 			 */
438 			goto bad;
439 		}
440 #endif
441 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
442 		m = NULL;
443 	}
444 
445 bad:
446 	if (m)
447 		m_freem(m);
448 	return;
449 
450 badcsum:
451 	m_freem(m);
452 }
453 #endif
454 
455 #ifdef INET
456 static void
457 udp4_sendup(struct mbuf *m, int off /* offset of data portion */,
458 	struct sockaddr *src, struct socket *so)
459 {
460 	struct mbuf *opts = NULL;
461 	struct mbuf *n;
462 	struct inpcb *inp = NULL;
463 
464 	if (!so)
465 		return;
466 	switch (so->so_proto->pr_domain->dom_family) {
467 	case AF_INET:
468 		inp = sotoinpcb(so);
469 		break;
470 #ifdef INET6
471 	case AF_INET6:
472 		break;
473 #endif
474 	default:
475 		return;
476 	}
477 
478 #if defined(IPSEC)
479 	/* check AH/ESP integrity. */
480 	if (ipsec_used && so != NULL && ipsec4_in_reject_so(m, so)) {
481 		IPSEC_STATINC(IPSEC_STAT_IN_POLVIO);
482 		if ((n = m_copypacket(m, M_DONTWAIT)) != NULL)
483 			icmp_error(n, ICMP_UNREACH, ICMP_UNREACH_ADMIN_PROHIBIT,
484 			    0, 0);
485 		return;
486 	}
487 #endif /*IPSEC*/
488 
489 	if ((n = m_copypacket(m, M_DONTWAIT)) != NULL) {
490 		if (inp && (inp->inp_flags & INP_CONTROLOPTS
491 #ifdef SO_OTIMESTAMP
492 			 || so->so_options & SO_OTIMESTAMP
493 #endif
494 			 || so->so_options & SO_TIMESTAMP)) {
495 			struct ip *ip = mtod(n, struct ip *);
496 			ip_savecontrol(inp, &opts, ip, n);
497 		}
498 
499 		m_adj(n, off);
500 		if (sbappendaddr(&so->so_rcv, src, n,
501 				opts) == 0) {
502 			m_freem(n);
503 			if (opts)
504 				m_freem(opts);
505 			so->so_rcv.sb_overflowed++;
506 			UDP_STATINC(UDP_STAT_FULLSOCK);
507 		} else
508 			sorwakeup(so);
509 	}
510 }
511 #endif
512 
513 #ifdef INET
514 static int
515 udp4_realinput(struct sockaddr_in *src, struct sockaddr_in *dst,
516 	struct mbuf **mp, int off /* offset of udphdr */)
517 {
518 	u_int16_t *sport, *dport;
519 	int rcvcnt;
520 	struct in_addr *src4, *dst4;
521 	struct inpcb_hdr *inph;
522 	struct inpcb *inp;
523 	struct mbuf *m = *mp;
524 
525 	rcvcnt = 0;
526 	off += sizeof(struct udphdr);	/* now, offset of payload */
527 
528 	if (src->sin_family != AF_INET || dst->sin_family != AF_INET)
529 		goto bad;
530 
531 	src4 = &src->sin_addr;
532 	sport = &src->sin_port;
533 	dst4 = &dst->sin_addr;
534 	dport = &dst->sin_port;
535 
536 	if (IN_MULTICAST(dst4->s_addr) ||
537 	    in_broadcast(*dst4, m->m_pkthdr.rcvif)) {
538 		/*
539 		 * Deliver a multicast or broadcast datagram to *all* sockets
540 		 * for which the local and remote addresses and ports match
541 		 * those of the incoming datagram.  This allows more than
542 		 * one process to receive multi/broadcasts on the same port.
543 		 * (This really ought to be done for unicast datagrams as
544 		 * well, but that would cause problems with existing
545 		 * applications that open both address-specific sockets and
546 		 * a wildcard socket listening to the same port -- they would
547 		 * end up receiving duplicates of every unicast datagram.
548 		 * Those applications open the multiple sockets to overcome an
549 		 * inadequacy of the UDP socket interface, but for backwards
550 		 * compatibility we avoid the problem here rather than
551 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
552 		 */
553 
554 		/*
555 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
556 		 * we need udpiphdr for IPsec processing so we do that later.
557 		 */
558 		/*
559 		 * Locate pcb(s) for datagram.
560 		 */
561 		TAILQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
562 			inp = (struct inpcb *)inph;
563 			if (inp->inp_af != AF_INET)
564 				continue;
565 
566 			if (inp->inp_lport != *dport)
567 				continue;
568 			if (!in_nullhost(inp->inp_laddr)) {
569 				if (!in_hosteq(inp->inp_laddr, *dst4))
570 					continue;
571 			}
572 			if (!in_nullhost(inp->inp_faddr)) {
573 				if (!in_hosteq(inp->inp_faddr, *src4) ||
574 				    inp->inp_fport != *sport)
575 					continue;
576 			}
577 
578 			udp4_sendup(m, off, (struct sockaddr *)src,
579 				inp->inp_socket);
580 			rcvcnt++;
581 
582 			/*
583 			 * Don't look for additional matches if this one does
584 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
585 			 * socket options set.  This heuristic avoids searching
586 			 * through all pcbs in the common case of a non-shared
587 			 * port.  It assumes that an application will never
588 			 * clear these options after setting them.
589 			 */
590 			if ((inp->inp_socket->so_options &
591 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
592 				break;
593 		}
594 	} else {
595 		/*
596 		 * Locate pcb for datagram.
597 		 */
598 		inp = in_pcblookup_connect(&udbtable, *src4, *sport, *dst4,
599 		    *dport, 0);
600 		if (inp == 0) {
601 			UDP_STATINC(UDP_STAT_PCBHASHMISS);
602 			inp = in_pcblookup_bind(&udbtable, *dst4, *dport);
603 			if (inp == 0)
604 				return rcvcnt;
605 		}
606 
607 #ifdef IPSEC
608 		/* Handle ESP over UDP */
609 		if (inp->inp_flags & INP_ESPINUDP_ALL) {
610 			struct sockaddr *sa = (struct sockaddr *)src;
611 
612 			switch(udp4_espinudp(mp, off, sa, inp->inp_socket)) {
613 			case -1: 	/* Error, m was freeed */
614 				rcvcnt = -1;
615 				goto bad;
616 				break;
617 
618 			case 1:		/* ESP over UDP */
619 				rcvcnt++;
620 				goto bad;
621 				break;
622 
623 			case 0: 	/* plain UDP */
624 			default: 	/* Unexpected */
625 				/*
626 				 * Normal UDP processing will take place
627 				 * m may have changed.
628 				 */
629 				m = *mp;
630 				break;
631 			}
632 		}
633 #endif
634 
635 		/*
636 		 * Check the minimum TTL for socket.
637 		 */
638 		if (mtod(m, struct ip *)->ip_ttl < inp->inp_ip_minttl)
639 			goto bad;
640 
641 		udp4_sendup(m, off, (struct sockaddr *)src, inp->inp_socket);
642 		rcvcnt++;
643 	}
644 
645 bad:
646 	return rcvcnt;
647 }
648 #endif
649 
650 #ifdef INET
651 /*
652  * Notify a udp user of an asynchronous error;
653  * just wake up so that he can collect error status.
654  */
655 static void
656 udp_notify(struct inpcb *inp, int errno)
657 {
658 	inp->inp_socket->so_error = errno;
659 	sorwakeup(inp->inp_socket);
660 	sowwakeup(inp->inp_socket);
661 }
662 
663 void *
664 udp_ctlinput(int cmd, const struct sockaddr *sa, void *v)
665 {
666 	struct ip *ip = v;
667 	struct udphdr *uh;
668 	void (*notify)(struct inpcb *, int) = udp_notify;
669 	int errno;
670 
671 	if (sa->sa_family != AF_INET
672 	 || sa->sa_len != sizeof(struct sockaddr_in))
673 		return NULL;
674 	if ((unsigned)cmd >= PRC_NCMDS)
675 		return NULL;
676 	errno = inetctlerrmap[cmd];
677 	if (PRC_IS_REDIRECT(cmd))
678 		notify = in_rtchange, ip = 0;
679 	else if (cmd == PRC_HOSTDEAD)
680 		ip = 0;
681 	else if (errno == 0)
682 		return NULL;
683 	if (ip) {
684 		uh = (struct udphdr *)((char *)ip + (ip->ip_hl << 2));
685 		in_pcbnotify(&udbtable, satocsin(sa)->sin_addr, uh->uh_dport,
686 		    ip->ip_src, uh->uh_sport, errno, notify);
687 
688 		/* XXX mapped address case */
689 	} else
690 		in_pcbnotifyall(&udbtable, satocsin(sa)->sin_addr, errno,
691 		    notify);
692 	return NULL;
693 }
694 
695 int
696 udp_ctloutput(int op, struct socket *so, struct sockopt *sopt)
697 {
698 	int s;
699 	int error = 0;
700 	struct inpcb *inp;
701 	int family;
702 	int optval;
703 
704 	family = so->so_proto->pr_domain->dom_family;
705 
706 	s = splsoftnet();
707 	switch (family) {
708 #ifdef INET
709 	case PF_INET:
710 		if (sopt->sopt_level != IPPROTO_UDP) {
711 			error = ip_ctloutput(op, so, sopt);
712 			goto end;
713 		}
714 		break;
715 #endif
716 #ifdef INET6
717 	case PF_INET6:
718 		if (sopt->sopt_level != IPPROTO_UDP) {
719 			error = ip6_ctloutput(op, so, sopt);
720 			goto end;
721 		}
722 		break;
723 #endif
724 	default:
725 		error = EAFNOSUPPORT;
726 		goto end;
727 	}
728 
729 
730 	switch (op) {
731 	case PRCO_SETOPT:
732 		inp = sotoinpcb(so);
733 
734 		switch (sopt->sopt_name) {
735 		case UDP_ENCAP:
736 			error = sockopt_getint(sopt, &optval);
737 			if (error)
738 				break;
739 
740 			switch(optval) {
741 			case 0:
742 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
743 				break;
744 
745 			case UDP_ENCAP_ESPINUDP:
746 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
747 				inp->inp_flags |= INP_ESPINUDP;
748 				break;
749 
750 			case UDP_ENCAP_ESPINUDP_NON_IKE:
751 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
752 				inp->inp_flags |= INP_ESPINUDP_NON_IKE;
753 				break;
754 			default:
755 				error = EINVAL;
756 				break;
757 			}
758 			break;
759 
760 		default:
761 			error = ENOPROTOOPT;
762 			break;
763 		}
764 		break;
765 
766 	default:
767 		error = EINVAL;
768 		break;
769 	}
770 
771 end:
772 	splx(s);
773 	return error;
774 }
775 
776 
777 int
778 udp_output(struct mbuf *m, struct inpcb *inp)
779 {
780 	struct udpiphdr *ui;
781 	struct route *ro;
782 	int len = m->m_pkthdr.len;
783 	int error = 0;
784 
785 	MCLAIM(m, &udp_tx_mowner);
786 
787 	/*
788 	 * Calculate data length and get a mbuf
789 	 * for UDP and IP headers.
790 	 */
791 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
792 	if (m == 0) {
793 		error = ENOBUFS;
794 		goto release;
795 	}
796 
797 	/*
798 	 * Compute the packet length of the IP header, and
799 	 * punt if the length looks bogus.
800 	 */
801 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
802 		error = EMSGSIZE;
803 		goto release;
804 	}
805 
806 	/*
807 	 * Fill in mbuf with extended UDP header
808 	 * and addresses and length put into network format.
809 	 */
810 	ui = mtod(m, struct udpiphdr *);
811 	ui->ui_pr = IPPROTO_UDP;
812 	ui->ui_src = inp->inp_laddr;
813 	ui->ui_dst = inp->inp_faddr;
814 	ui->ui_sport = inp->inp_lport;
815 	ui->ui_dport = inp->inp_fport;
816 	ui->ui_ulen = htons((u_int16_t)len + sizeof(struct udphdr));
817 
818 	ro = &inp->inp_route;
819 
820 	/*
821 	 * Set up checksum and output datagram.
822 	 */
823 	if (udpcksum) {
824 		/*
825 		 * XXX Cache pseudo-header checksum part for
826 		 * XXX "connected" UDP sockets.
827 		 */
828 		ui->ui_sum = in_cksum_phdr(ui->ui_src.s_addr,
829 		    ui->ui_dst.s_addr, htons((u_int16_t)len +
830 		    sizeof(struct udphdr) + IPPROTO_UDP));
831 		m->m_pkthdr.csum_flags = M_CSUM_UDPv4;
832 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
833 	} else
834 		ui->ui_sum = 0;
835 	((struct ip *)ui)->ip_len = htons(sizeof (struct udpiphdr) + len);
836 	((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;	/* XXX */
837 	((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;	/* XXX */
838 	UDP_STATINC(UDP_STAT_OPACKETS);
839 
840 	return (ip_output(m, inp->inp_options, ro,
841 	    inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST),
842 	    inp->inp_moptions, inp->inp_socket));
843 
844 release:
845 	m_freem(m);
846 	return (error);
847 }
848 
849 static int
850 udp_attach(struct socket *so, int proto)
851 {
852 	struct inpcb *inp;
853 	int error;
854 
855 	KASSERT(sotoinpcb(so) == NULL);
856 
857 	/* Assign the lock (must happen even if we will error out). */
858 	sosetlock(so);
859 
860 #ifdef MBUFTRACE
861 	so->so_mowner = &udp_mowner;
862 	so->so_rcv.sb_mowner = &udp_rx_mowner;
863 	so->so_snd.sb_mowner = &udp_tx_mowner;
864 #endif
865 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
866 		error = soreserve(so, udp_sendspace, udp_recvspace);
867 		if (error) {
868 			return error;
869 		}
870 	}
871 
872 	error = in_pcballoc(so, &udbtable);
873 	if (error) {
874 		return error;
875 	}
876 	inp = sotoinpcb(so);
877 	inp->inp_ip.ip_ttl = ip_defttl;
878 	KASSERT(solocked(so));
879 
880 	return error;
881 }
882 
883 static void
884 udp_detach(struct socket *so)
885 {
886 	struct inpcb *inp;
887 
888 	KASSERT(solocked(so));
889 	inp = sotoinpcb(so);
890 	KASSERT(inp != NULL);
891 	in_pcbdetach(inp);
892 }
893 
894 static int
895 udp_accept(struct socket *so, struct sockaddr *nam)
896 {
897 	KASSERT(solocked(so));
898 
899 	panic("udp_accept");
900 
901 	return EOPNOTSUPP;
902 }
903 
904 static int
905 udp_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
906 {
907 	struct inpcb *inp = sotoinpcb(so);
908 	struct sockaddr_in *sin = (struct sockaddr_in *)nam;
909 	int error = 0;
910 	int s;
911 
912 	KASSERT(solocked(so));
913 	KASSERT(inp != NULL);
914 	KASSERT(nam != NULL);
915 
916 	s = splsoftnet();
917 	error = in_pcbbind(inp, sin, l);
918 	splx(s);
919 
920 	return error;
921 }
922 
923 static int
924 udp_listen(struct socket *so, struct lwp *l)
925 {
926 	KASSERT(solocked(so));
927 
928 	return EOPNOTSUPP;
929 }
930 
931 static int
932 udp_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
933 {
934 	struct inpcb *inp = sotoinpcb(so);
935 	int error = 0;
936 	int s;
937 
938 	KASSERT(solocked(so));
939 	KASSERT(inp != NULL);
940 	KASSERT(nam != NULL);
941 
942 	s = splsoftnet();
943 	error = in_pcbconnect(inp, (struct sockaddr_in *)nam, l);
944 	if (! error)
945 		soisconnected(so);
946 	splx(s);
947 	return error;
948 }
949 
950 static int
951 udp_connect2(struct socket *so, struct socket *so2)
952 {
953 	KASSERT(solocked(so));
954 
955 	return EOPNOTSUPP;
956 }
957 
958 static int
959 udp_disconnect(struct socket *so)
960 {
961 	struct inpcb *inp = sotoinpcb(so);
962 	int s;
963 
964 	KASSERT(solocked(so));
965 	KASSERT(inp != NULL);
966 
967 	s = splsoftnet();
968 	/*soisdisconnected(so);*/
969 	so->so_state &= ~SS_ISCONNECTED;	/* XXX */
970 	in_pcbdisconnect(inp);
971 	inp->inp_laddr = zeroin_addr;		/* XXX */
972 	in_pcbstate(inp, INP_BOUND);		/* XXX */
973 	splx(s);
974 
975 	return 0;
976 }
977 
978 static int
979 udp_shutdown(struct socket *so)
980 {
981 	int s;
982 
983 	KASSERT(solocked(so));
984 
985 	s = splsoftnet();
986 	socantsendmore(so);
987 	splx(s);
988 
989 	return 0;
990 }
991 
992 static int
993 udp_abort(struct socket *so)
994 {
995 	KASSERT(solocked(so));
996 
997 	panic("udp_abort");
998 
999 	return EOPNOTSUPP;
1000 }
1001 
1002 static int
1003 udp_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp)
1004 {
1005 	return in_control(so, cmd, nam, ifp);
1006 }
1007 
1008 static int
1009 udp_stat(struct socket *so, struct stat *ub)
1010 {
1011 	KASSERT(solocked(so));
1012 
1013 	/* stat: don't bother with a blocksize. */
1014 	return 0;
1015 }
1016 
1017 static int
1018 udp_peeraddr(struct socket *so, struct sockaddr *nam)
1019 {
1020 	int s;
1021 
1022 	KASSERT(solocked(so));
1023 	KASSERT(sotoinpcb(so) != NULL);
1024 	KASSERT(nam != NULL);
1025 
1026 	s = splsoftnet();
1027 	in_setpeeraddr(sotoinpcb(so), (struct sockaddr_in *)nam);
1028 	splx(s);
1029 
1030 	return 0;
1031 }
1032 
1033 static int
1034 udp_sockaddr(struct socket *so, struct sockaddr *nam)
1035 {
1036 	int s;
1037 
1038 	KASSERT(solocked(so));
1039 	KASSERT(sotoinpcb(so) != NULL);
1040 	KASSERT(nam != NULL);
1041 
1042 	s = splsoftnet();
1043 	in_setsockaddr(sotoinpcb(so), (struct sockaddr_in *)nam);
1044 	splx(s);
1045 
1046 	return 0;
1047 }
1048 
1049 static int
1050 udp_rcvd(struct socket *so, int flags, struct lwp *l)
1051 {
1052 	KASSERT(solocked(so));
1053 
1054 	return EOPNOTSUPP;
1055 }
1056 
1057 static int
1058 udp_recvoob(struct socket *so, struct mbuf *m, int flags)
1059 {
1060 	KASSERT(solocked(so));
1061 
1062 	return EOPNOTSUPP;
1063 }
1064 
1065 static int
1066 udp_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
1067     struct mbuf *control, struct lwp *l)
1068 {
1069 	struct inpcb *inp = sotoinpcb(so);
1070 	int error = 0;
1071 	struct in_addr laddr;			/* XXX */
1072 	int s;
1073 
1074 	KASSERT(solocked(so));
1075 	KASSERT(inp != NULL);
1076 	KASSERT(m != NULL);
1077 
1078 	if (control && control->m_len) {
1079 		m_freem(control);
1080 		m_freem(m);
1081 		return EINVAL;
1082 	}
1083 
1084 	memset(&laddr, 0, sizeof laddr);
1085 
1086 	s = splsoftnet();
1087 	if (nam) {
1088 		laddr = inp->inp_laddr;		/* XXX */
1089 		if ((so->so_state & SS_ISCONNECTED) != 0) {
1090 			error = EISCONN;
1091 			goto die;
1092 		}
1093 		error = in_pcbconnect(inp, (struct sockaddr_in *)nam, l);
1094 		if (error)
1095 			goto die;
1096 	} else {
1097 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1098 			error = ENOTCONN;
1099 			goto die;
1100 		}
1101 	}
1102 	error = udp_output(m, inp);
1103 	m = NULL;
1104 	if (nam) {
1105 		in_pcbdisconnect(inp);
1106 		inp->inp_laddr = laddr;		/* XXX */
1107 		in_pcbstate(inp, INP_BOUND);	/* XXX */
1108 	}
1109   die:
1110 	if (m)
1111 		m_freem(m);
1112 
1113 	splx(s);
1114 	return error;
1115 }
1116 
1117 static int
1118 udp_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
1119 {
1120 	KASSERT(solocked(so));
1121 
1122 	m_freem(m);
1123 	m_freem(control);
1124 
1125 	return EOPNOTSUPP;
1126 }
1127 
1128 static int
1129 udp_purgeif(struct socket *so, struct ifnet *ifp)
1130 {
1131 	int s;
1132 
1133 	s = splsoftnet();
1134 	mutex_enter(softnet_lock);
1135 	in_pcbpurgeif0(&udbtable, ifp);
1136 	in_purgeif(ifp);
1137 	in_pcbpurgeif(&udbtable, ifp);
1138 	mutex_exit(softnet_lock);
1139 	splx(s);
1140 
1141 	return 0;
1142 }
1143 
1144 static int
1145 sysctl_net_inet_udp_stats(SYSCTLFN_ARGS)
1146 {
1147 
1148 	return (NETSTAT_SYSCTL(udpstat_percpu, UDP_NSTATS));
1149 }
1150 
1151 /*
1152  * Sysctl for udp variables.
1153  */
1154 static void
1155 sysctl_net_inet_udp_setup(struct sysctllog **clog)
1156 {
1157 
1158 	sysctl_createv(clog, 0, NULL, NULL,
1159 		       CTLFLAG_PERMANENT,
1160 		       CTLTYPE_NODE, "inet", NULL,
1161 		       NULL, 0, NULL, 0,
1162 		       CTL_NET, PF_INET, CTL_EOL);
1163 	sysctl_createv(clog, 0, NULL, NULL,
1164 		       CTLFLAG_PERMANENT,
1165 		       CTLTYPE_NODE, "udp",
1166 		       SYSCTL_DESCR("UDPv4 related settings"),
1167 		       NULL, 0, NULL, 0,
1168 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_EOL);
1169 
1170 	sysctl_createv(clog, 0, NULL, NULL,
1171 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1172 		       CTLTYPE_INT, "checksum",
1173 		       SYSCTL_DESCR("Compute UDP checksums"),
1174 		       NULL, 0, &udpcksum, 0,
1175 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_CHECKSUM,
1176 		       CTL_EOL);
1177 	sysctl_createv(clog, 0, NULL, NULL,
1178 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1179 		       CTLTYPE_INT, "sendspace",
1180 		       SYSCTL_DESCR("Default UDP send buffer size"),
1181 		       NULL, 0, &udp_sendspace, 0,
1182 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_SENDSPACE,
1183 		       CTL_EOL);
1184 	sysctl_createv(clog, 0, NULL, NULL,
1185 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1186 		       CTLTYPE_INT, "recvspace",
1187 		       SYSCTL_DESCR("Default UDP receive buffer size"),
1188 		       NULL, 0, &udp_recvspace, 0,
1189 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_RECVSPACE,
1190 		       CTL_EOL);
1191 	sysctl_createv(clog, 0, NULL, NULL,
1192 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1193 		       CTLTYPE_INT, "do_loopback_cksum",
1194 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
1195 		       NULL, 0, &udp_do_loopback_cksum, 0,
1196 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_LOOPBACKCKSUM,
1197 		       CTL_EOL);
1198 	sysctl_createv(clog, 0, NULL, NULL,
1199 		       CTLFLAG_PERMANENT,
1200 		       CTLTYPE_STRUCT, "pcblist",
1201 		       SYSCTL_DESCR("UDP protocol control block list"),
1202 		       sysctl_inpcblist, 0, &udbtable, 0,
1203 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_CREATE,
1204 		       CTL_EOL);
1205 	sysctl_createv(clog, 0, NULL, NULL,
1206 		       CTLFLAG_PERMANENT,
1207 		       CTLTYPE_STRUCT, "stats",
1208 		       SYSCTL_DESCR("UDP statistics"),
1209 		       sysctl_net_inet_udp_stats, 0, NULL, 0,
1210 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_STATS,
1211 		       CTL_EOL);
1212 }
1213 #endif
1214 
1215 void
1216 udp_statinc(u_int stat)
1217 {
1218 
1219 	KASSERT(stat < UDP_NSTATS);
1220 	UDP_STATINC(stat);
1221 }
1222 
1223 #if defined(INET) && defined(IPSEC)
1224 /*
1225  * Returns:
1226  * 1 if the packet was processed
1227  * 0 if normal UDP processing should take place
1228  * -1 if an error occurent and m was freed
1229  */
1230 static int
1231 udp4_espinudp(struct mbuf **mp, int off, struct sockaddr *src,
1232     struct socket *so)
1233 {
1234 	size_t len;
1235 	void *data;
1236 	struct inpcb *inp;
1237 	size_t skip = 0;
1238 	size_t minlen;
1239 	size_t iphdrlen;
1240 	struct ip *ip;
1241 	struct m_tag *tag;
1242 	struct udphdr *udphdr;
1243 	u_int16_t sport, dport;
1244 	struct mbuf *m = *mp;
1245 
1246 	/*
1247 	 * Collapse the mbuf chain if the first mbuf is too short
1248 	 * The longest case is: UDP + non ESP marker + ESP
1249 	 */
1250 	minlen = off + sizeof(u_int64_t) + sizeof(struct esp);
1251 	if (minlen > m->m_pkthdr.len)
1252 		minlen = m->m_pkthdr.len;
1253 
1254 	if (m->m_len < minlen) {
1255 		if ((*mp = m_pullup(m, minlen)) == NULL) {
1256 			printf("udp4_espinudp: m_pullup failed\n");
1257 			return -1;
1258 		}
1259 		m = *mp;
1260 	}
1261 
1262 	len = m->m_len - off;
1263 	data = mtod(m, char *) + off;
1264 	inp = sotoinpcb(so);
1265 
1266 	/* Ignore keepalive packets */
1267 	if ((len == 1) && (*(unsigned char *)data == 0xff)) {
1268 		m_free(m);
1269 		*mp = NULL; /* avoid any further processiong by caller ... */
1270 		return 1;
1271 	}
1272 
1273 	/*
1274 	 * Check that the payload is long enough to hold
1275 	 * an ESP header and compute the length of encapsulation
1276 	 * header to remove
1277 	 */
1278 	if (inp->inp_flags & INP_ESPINUDP) {
1279 		u_int32_t *st = (u_int32_t *)data;
1280 
1281 		if ((len <= sizeof(struct esp)) || (*st == 0))
1282 			return 0; /* Normal UDP processing */
1283 
1284 		skip = sizeof(struct udphdr);
1285 	}
1286 
1287 	if (inp->inp_flags & INP_ESPINUDP_NON_IKE) {
1288 		u_int32_t *st = (u_int32_t *)data;
1289 
1290 		if ((len <= sizeof(u_int64_t) + sizeof(struct esp))
1291 		    || ((st[0] | st[1]) != 0))
1292 			return 0; /* Normal UDP processing */
1293 
1294 		skip = sizeof(struct udphdr) + sizeof(u_int64_t);
1295 	}
1296 
1297 	/*
1298 	 * Get the UDP ports. They are handled in network
1299 	 * order everywhere in IPSEC_NAT_T code.
1300 	 */
1301 	udphdr = (struct udphdr *)((char *)data - skip);
1302 	sport = udphdr->uh_sport;
1303 	dport = udphdr->uh_dport;
1304 
1305 	/*
1306 	 * Remove the UDP header (and possibly the non ESP marker)
1307 	 * IP header lendth is iphdrlen
1308 	 * Before:
1309 	 *   <--- off --->
1310 	 *   +----+------+-----+
1311 	 *   | IP |  UDP | ESP |
1312 	 *   +----+------+-----+
1313 	 *        <-skip->
1314 	 * After:
1315 	 *          +----+-----+
1316 	 *          | IP | ESP |
1317 	 *          +----+-----+
1318 	 *   <-skip->
1319 	 */
1320 	iphdrlen = off - sizeof(struct udphdr);
1321 	memmove(mtod(m, char *) + skip, mtod(m, void *), iphdrlen);
1322 	m_adj(m, skip);
1323 
1324 	ip = mtod(m, struct ip *);
1325 	ip->ip_len = htons(ntohs(ip->ip_len) - skip);
1326 	ip->ip_p = IPPROTO_ESP;
1327 
1328 	/*
1329 	 * We have modified the packet - it is now ESP, so we should not
1330 	 * return to UDP processing ...
1331 	 *
1332 	 * Add a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember
1333 	 * the source UDP port. This is required if we want
1334 	 * to select the right SPD for multiple hosts behind
1335 	 * same NAT
1336 	 */
1337 	if ((tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS,
1338 	    sizeof(sport) + sizeof(dport), M_DONTWAIT)) == NULL) {
1339 		printf("udp4_espinudp: m_tag_get failed\n");
1340 		m_freem(m);
1341 		return -1;
1342 	}
1343 	((u_int16_t *)(tag + 1))[0] = sport;
1344 	((u_int16_t *)(tag + 1))[1] = dport;
1345 	m_tag_prepend(m, tag);
1346 
1347 #ifdef IPSEC
1348 	if (ipsec_used)
1349 		ipsec4_common_input(m, iphdrlen, IPPROTO_ESP);
1350 	/* XXX: else */
1351 #else
1352 	esp4_input(m, iphdrlen);
1353 #endif
1354 
1355 	/* We handled it, it shouldn't be handled by UDP */
1356 	*mp = NULL; /* avoid free by caller ... */
1357 	return 1;
1358 }
1359 #endif
1360 
1361 PR_WRAP_USRREQS(udp)
1362 #define	udp_attach	udp_attach_wrapper
1363 #define	udp_detach	udp_detach_wrapper
1364 #define	udp_accept	udp_accept_wrapper
1365 #define	udp_bind	udp_bind_wrapper
1366 #define	udp_listen	udp_listen_wrapper
1367 #define	udp_connect	udp_connect_wrapper
1368 #define	udp_connect2	udp_connect2_wrapper
1369 #define	udp_disconnect	udp_disconnect_wrapper
1370 #define	udp_shutdown	udp_shutdown_wrapper
1371 #define	udp_abort	udp_abort_wrapper
1372 #define	udp_ioctl	udp_ioctl_wrapper
1373 #define	udp_stat	udp_stat_wrapper
1374 #define	udp_peeraddr	udp_peeraddr_wrapper
1375 #define	udp_sockaddr	udp_sockaddr_wrapper
1376 #define	udp_rcvd	udp_rcvd_wrapper
1377 #define	udp_recvoob	udp_recvoob_wrapper
1378 #define	udp_send	udp_send_wrapper
1379 #define	udp_sendoob	udp_sendoob_wrapper
1380 #define	udp_purgeif	udp_purgeif_wrapper
1381 
1382 const struct pr_usrreqs udp_usrreqs = {
1383 	.pr_attach	= udp_attach,
1384 	.pr_detach	= udp_detach,
1385 	.pr_accept	= udp_accept,
1386 	.pr_bind	= udp_bind,
1387 	.pr_listen	= udp_listen,
1388 	.pr_connect	= udp_connect,
1389 	.pr_connect2	= udp_connect2,
1390 	.pr_disconnect	= udp_disconnect,
1391 	.pr_shutdown	= udp_shutdown,
1392 	.pr_abort	= udp_abort,
1393 	.pr_ioctl	= udp_ioctl,
1394 	.pr_stat	= udp_stat,
1395 	.pr_peeraddr	= udp_peeraddr,
1396 	.pr_sockaddr	= udp_sockaddr,
1397 	.pr_rcvd	= udp_rcvd,
1398 	.pr_recvoob	= udp_recvoob,
1399 	.pr_send	= udp_send,
1400 	.pr_sendoob	= udp_sendoob,
1401 	.pr_purgeif	= udp_purgeif,
1402 };
1403