xref: /netbsd-src/sys/netinet/udp_usrreq.c (revision c9496f6b604074a9451a67df576a5b423068e71e)
1 /*	$NetBSD: udp_usrreq.c,v 1.236 2017/12/11 05:47:18 ryo 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 1.236 2017/12/11 05:47:18 ryo Exp $");
70 
71 #ifdef _KERNEL_OPT
72 #include "opt_inet.h"
73 #include "opt_ipsec.h"
74 #include "opt_inet_csum.h"
75 #include "opt_ipkdb.h"
76 #include "opt_mbuftrace.h"
77 #include "opt_net_mpsafe.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 
93 #include <netinet/in.h>
94 #include <netinet/in_systm.h>
95 #include <netinet/in_var.h>
96 #include <netinet/ip.h>
97 #include <netinet/in_pcb.h>
98 #include <netinet/ip_var.h>
99 #include <netinet/ip_icmp.h>
100 #include <netinet/udp.h>
101 #include <netinet/udp_var.h>
102 #include <netinet/udp_private.h>
103 
104 #ifdef INET6
105 #include <netinet/ip6.h>
106 #include <netinet/icmp6.h>
107 #include <netinet6/ip6_var.h>
108 #include <netinet6/ip6_private.h>
109 #include <netinet6/in6_pcb.h>
110 #include <netinet6/udp6_var.h>
111 #include <netinet6/udp6_private.h>
112 #endif
113 
114 #ifndef INET6
115 /* always need ip6.h for IP6_EXTHDR_GET */
116 #include <netinet/ip6.h>
117 #endif
118 
119 #ifdef IPSEC
120 #include <netipsec/ipsec.h>
121 #include <netipsec/ipsec_var.h>
122 #include <netipsec/ipsec_private.h>
123 #include <netipsec/esp.h>
124 #ifdef INET6
125 #include <netipsec/ipsec6.h>
126 #endif
127 #endif	/* IPSEC */
128 
129 #ifdef IPKDB
130 #include <ipkdb/ipkdb.h>
131 #endif
132 
133 int	udpcksum = 1;
134 int	udp_do_loopback_cksum = 0;
135 
136 struct	inpcbtable udbtable;
137 
138 percpu_t *udpstat_percpu;
139 
140 #ifdef INET
141 #ifdef IPSEC
142 static int udp4_espinudp (struct mbuf **, int, struct sockaddr *,
143 	struct socket *);
144 #endif
145 static void udp4_sendup (struct mbuf *, int, struct sockaddr *,
146 	struct socket *);
147 static int udp4_realinput (struct sockaddr_in *, struct sockaddr_in *,
148 	struct mbuf **, int);
149 static int udp4_input_checksum(struct mbuf *, const struct udphdr *, int, int);
150 #endif
151 #ifdef INET
152 static	void udp_notify (struct inpcb *, int);
153 #endif
154 
155 #ifndef UDBHASHSIZE
156 #define	UDBHASHSIZE	128
157 #endif
158 int	udbhashsize = UDBHASHSIZE;
159 
160 /*
161  * For send - really max datagram size; for receive - 40 1K datagrams.
162  */
163 static int	udp_sendspace = 9216;
164 static int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
165 
166 #ifdef MBUFTRACE
167 struct mowner udp_mowner = MOWNER_INIT("udp", "");
168 struct mowner udp_rx_mowner = MOWNER_INIT("udp", "rx");
169 struct mowner udp_tx_mowner = MOWNER_INIT("udp", "tx");
170 #endif
171 
172 #ifdef UDP_CSUM_COUNTERS
173 #include <sys/device.h>
174 
175 #if defined(INET)
176 struct evcnt udp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
177     NULL, "udp", "hwcsum bad");
178 struct evcnt udp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
179     NULL, "udp", "hwcsum ok");
180 struct evcnt udp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
181     NULL, "udp", "hwcsum data");
182 struct evcnt udp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
183     NULL, "udp", "swcsum");
184 
185 EVCNT_ATTACH_STATIC(udp_hwcsum_bad);
186 EVCNT_ATTACH_STATIC(udp_hwcsum_ok);
187 EVCNT_ATTACH_STATIC(udp_hwcsum_data);
188 EVCNT_ATTACH_STATIC(udp_swcsum);
189 #endif /* defined(INET) */
190 
191 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
192 #else
193 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
194 #endif /* UDP_CSUM_COUNTERS */
195 
196 static void sysctl_net_inet_udp_setup(struct sysctllog **);
197 
198 static int
199 do_udpinit(void)
200 {
201 
202 	in_pcbinit(&udbtable, udbhashsize, udbhashsize);
203 	udpstat_percpu = percpu_alloc(sizeof(uint64_t) * UDP_NSTATS);
204 
205 	MOWNER_ATTACH(&udp_tx_mowner);
206 	MOWNER_ATTACH(&udp_rx_mowner);
207 	MOWNER_ATTACH(&udp_mowner);
208 
209 	return 0;
210 }
211 
212 void
213 udp_init_common(void)
214 {
215 	static ONCE_DECL(doudpinit);
216 
217 	RUN_ONCE(&doudpinit, do_udpinit);
218 }
219 
220 void
221 udp_init(void)
222 {
223 
224 	sysctl_net_inet_udp_setup(NULL);
225 
226 	udp_init_common();
227 }
228 
229 /*
230  * Checksum extended UDP header and data.
231  */
232 
233 int
234 udp_input_checksum(int af, struct mbuf *m, const struct udphdr *uh,
235     int iphlen, int len)
236 {
237 
238 	switch (af) {
239 #ifdef INET
240 	case AF_INET:
241 		return udp4_input_checksum(m, uh, iphlen, len);
242 #endif
243 #ifdef INET6
244 	case AF_INET6:
245 		return udp6_input_checksum(m, uh, iphlen, len);
246 #endif
247 	}
248 #ifdef DIAGNOSTIC
249 	panic("udp_input_checksum: unknown af %d", af);
250 #endif
251 	/* NOTREACHED */
252 	return -1;
253 }
254 
255 #ifdef INET
256 
257 /*
258  * Checksum extended UDP header and data.
259  */
260 
261 static int
262 udp4_input_checksum(struct mbuf *m, const struct udphdr *uh,
263     int iphlen, int len)
264 {
265 
266 	/*
267 	 * XXX it's better to record and check if this mbuf is
268 	 * already checked.
269 	 */
270 
271 	if (uh->uh_sum == 0)
272 		return 0;
273 
274 	switch (m->m_pkthdr.csum_flags &
275 	    ((m_get_rcvif_NOMPSAFE(m)->if_csum_flags_rx & M_CSUM_UDPv4) |
276 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
277 	case M_CSUM_UDPv4|M_CSUM_TCP_UDP_BAD:
278 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_bad);
279 		goto badcsum;
280 
281 	case M_CSUM_UDPv4|M_CSUM_DATA: {
282 		u_int32_t hw_csum = m->m_pkthdr.csum_data;
283 
284 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_data);
285 		if (m->m_pkthdr.csum_flags & M_CSUM_NO_PSEUDOHDR) {
286 			const struct ip *ip =
287 			    mtod(m, const struct ip *);
288 
289 			hw_csum = in_cksum_phdr(ip->ip_src.s_addr,
290 			    ip->ip_dst.s_addr,
291 			    htons(hw_csum + len + IPPROTO_UDP));
292 		}
293 		if ((hw_csum ^ 0xffff) != 0)
294 			goto badcsum;
295 		break;
296 	}
297 
298 	case M_CSUM_UDPv4:
299 		/* Checksum was okay. */
300 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_ok);
301 		break;
302 
303 	default:
304 		/*
305 		 * Need to compute it ourselves.  Maybe skip checksum
306 		 * on loopback interfaces.
307 		 */
308 		if (__predict_true(!(m_get_rcvif_NOMPSAFE(m)->if_flags &
309 				     IFF_LOOPBACK) ||
310 				   udp_do_loopback_cksum)) {
311 			UDP_CSUM_COUNTER_INCR(&udp_swcsum);
312 			if (in4_cksum(m, IPPROTO_UDP, iphlen, len) != 0)
313 				goto badcsum;
314 		}
315 		break;
316 	}
317 
318 	return 0;
319 
320 badcsum:
321 	UDP_STATINC(UDP_STAT_BADSUM);
322 	return -1;
323 }
324 
325 void
326 udp_input(struct mbuf *m, ...)
327 {
328 	va_list ap;
329 	struct sockaddr_in src, dst;
330 	struct ip *ip;
331 	struct udphdr *uh;
332 	int iphlen;
333 	int len;
334 	int n;
335 	u_int16_t ip_len;
336 
337 	va_start(ap, m);
338 	iphlen = va_arg(ap, int);
339 	(void)va_arg(ap, int);		/* ignore value, advance ap */
340 	va_end(ap);
341 
342 	MCLAIM(m, &udp_rx_mowner);
343 	UDP_STATINC(UDP_STAT_IPACKETS);
344 
345 	/*
346 	 * Get IP and UDP header together in first mbuf.
347 	 */
348 	ip = mtod(m, struct ip *);
349 	IP6_EXTHDR_GET(uh, struct udphdr *, m, iphlen, sizeof(struct udphdr));
350 	if (uh == NULL) {
351 		UDP_STATINC(UDP_STAT_HDROPS);
352 		return;
353 	}
354 	/*
355 	 * Enforce alignment requirements that are violated in
356 	 * some cases, see kern/50766 for details.
357 	 */
358 	if (UDP_HDR_ALIGNED_P(uh) == 0) {
359 		m = m_copyup(m, iphlen + sizeof(struct udphdr), 0);
360 		if (m == NULL) {
361 			UDP_STATINC(UDP_STAT_HDROPS);
362 			return;
363 		}
364 		ip = mtod(m, struct ip *);
365 		uh = (struct udphdr *)(mtod(m, char *) + iphlen);
366 	}
367 	KASSERT(UDP_HDR_ALIGNED_P(uh));
368 
369 	/* destination port of 0 is illegal, based on RFC768. */
370 	if (uh->uh_dport == 0)
371 		goto bad;
372 
373 	/*
374 	 * Make mbuf data length reflect UDP length.
375 	 * If not enough data to reflect UDP length, drop.
376 	 */
377 	ip_len = ntohs(ip->ip_len);
378 	len = ntohs((u_int16_t)uh->uh_ulen);
379 	if (ip_len != iphlen + len) {
380 		if (ip_len < iphlen + len || len < sizeof(struct udphdr)) {
381 			UDP_STATINC(UDP_STAT_BADLEN);
382 			goto bad;
383 		}
384 		m_adj(m, iphlen + len - ip_len);
385 	}
386 
387 	/*
388 	 * Checksum extended UDP header and data.
389 	 */
390 	if (udp4_input_checksum(m, uh, iphlen, len))
391 		goto badcsum;
392 
393 	/* construct source and dst sockaddrs. */
394 	sockaddr_in_init(&src, &ip->ip_src, uh->uh_sport);
395 	sockaddr_in_init(&dst, &ip->ip_dst, uh->uh_dport);
396 
397 	if ((n = udp4_realinput(&src, &dst, &m, iphlen)) == -1) {
398 		UDP_STATINC(UDP_STAT_HDROPS);
399 		return;
400 	}
401 	if (m == NULL) {
402 		/*
403 		 * packet has been processed by ESP stuff -
404 		 * e.g. dropped NAT-T-keep-alive-packet ...
405 		 */
406 		return;
407 	}
408 	ip = mtod(m, struct ip *);
409 #ifdef INET6
410 	if (IN_MULTICAST(ip->ip_dst.s_addr) || n == 0) {
411 		struct sockaddr_in6 src6, dst6;
412 
413 		memset(&src6, 0, sizeof(src6));
414 		src6.sin6_family = AF_INET6;
415 		src6.sin6_len = sizeof(struct sockaddr_in6);
416 		in6_in_2_v4mapin6(&ip->ip_src, &src6.sin6_addr);
417 		src6.sin6_port = uh->uh_sport;
418 		memset(&dst6, 0, sizeof(dst6));
419 		dst6.sin6_family = AF_INET6;
420 		dst6.sin6_len = sizeof(struct sockaddr_in6);
421 		in6_in_2_v4mapin6(&ip->ip_dst, &dst6.sin6_addr);
422 		dst6.sin6_port = uh->uh_dport;
423 
424 		n += udp6_realinput(AF_INET, &src6, &dst6, m, iphlen);
425 	}
426 #endif
427 
428 	if (n == 0) {
429 		if (m->m_flags & (M_BCAST | M_MCAST)) {
430 			UDP_STATINC(UDP_STAT_NOPORTBCAST);
431 			goto bad;
432 		}
433 		UDP_STATINC(UDP_STAT_NOPORT);
434 #ifdef IPKDB
435 		if (checkipkdb(&ip->ip_src, uh->uh_sport, uh->uh_dport,
436 				m, iphlen + sizeof(struct udphdr),
437 				m->m_pkthdr.len - iphlen - sizeof(struct udphdr))) {
438 			/*
439 			 * It was a debugger connect packet,
440 			 * just drop it now
441 			 */
442 			goto bad;
443 		}
444 #endif
445 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
446 		m = NULL;
447 	}
448 
449 bad:
450 	if (m)
451 		m_freem(m);
452 	return;
453 
454 badcsum:
455 	m_freem(m);
456 }
457 #endif
458 
459 #ifdef INET
460 static void
461 udp4_sendup(struct mbuf *m, int off /* offset of data portion */,
462 	struct sockaddr *src, struct socket *so)
463 {
464 	struct mbuf *opts = NULL;
465 	struct mbuf *n;
466 	struct inpcb *inp;
467 
468 	KASSERT(so != NULL);
469 	KASSERT(so->so_proto->pr_domain->dom_family == AF_INET);
470 	inp = sotoinpcb(so);
471 	KASSERT(inp != NULL);
472 
473 #if defined(IPSEC)
474 	/* check AH/ESP integrity. */
475 	if (ipsec_used && ipsec4_in_reject(m, inp)) {
476 		IPSEC_STATINC(IPSEC_STAT_IN_POLVIO);
477 		if ((n = m_copypacket(m, M_DONTWAIT)) != NULL)
478 			icmp_error(n, ICMP_UNREACH, ICMP_UNREACH_ADMIN_PROHIBIT,
479 			    0, 0);
480 		return;
481 	}
482 #endif /*IPSEC*/
483 
484 	if ((n = m_copypacket(m, M_DONTWAIT)) != NULL) {
485 		if (inp->inp_flags & INP_CONTROLOPTS
486 		    || SOOPT_TIMESTAMP(so->so_options)) {
487 			struct ip *ip = mtod(n, struct ip *);
488 			ip_savecontrol(inp, &opts, ip, n);
489 		}
490 
491 		m_adj(n, off);
492 		if (sbappendaddr(&so->so_rcv, src, n,
493 				opts) == 0) {
494 			m_freem(n);
495 			if (opts)
496 				m_freem(opts);
497 			so->so_rcv.sb_overflowed++;
498 			UDP_STATINC(UDP_STAT_FULLSOCK);
499 		} else
500 			sorwakeup(so);
501 	}
502 }
503 #endif
504 
505 #ifdef INET
506 static int
507 udp4_realinput(struct sockaddr_in *src, struct sockaddr_in *dst,
508 	struct mbuf **mp, int off /* offset of udphdr */)
509 {
510 	u_int16_t *sport, *dport;
511 	int rcvcnt;
512 	struct in_addr *src4, *dst4;
513 	struct inpcb_hdr *inph;
514 	struct inpcb *inp;
515 	struct mbuf *m = *mp;
516 
517 	rcvcnt = 0;
518 	off += sizeof(struct udphdr);	/* now, offset of payload */
519 
520 	if (src->sin_family != AF_INET || dst->sin_family != AF_INET)
521 		goto bad;
522 
523 	src4 = &src->sin_addr;
524 	sport = &src->sin_port;
525 	dst4 = &dst->sin_addr;
526 	dport = &dst->sin_port;
527 
528 	if (IN_MULTICAST(dst4->s_addr) ||
529 	    in_broadcast(*dst4, m_get_rcvif_NOMPSAFE(m))) {
530 		/*
531 		 * Deliver a multicast or broadcast datagram to *all* sockets
532 		 * for which the local and remote addresses and ports match
533 		 * those of the incoming datagram.  This allows more than
534 		 * one process to receive multi/broadcasts on the same port.
535 		 * (This really ought to be done for unicast datagrams as
536 		 * well, but that would cause problems with existing
537 		 * applications that open both address-specific sockets and
538 		 * a wildcard socket listening to the same port -- they would
539 		 * end up receiving duplicates of every unicast datagram.
540 		 * Those applications open the multiple sockets to overcome an
541 		 * inadequacy of the UDP socket interface, but for backwards
542 		 * compatibility we avoid the problem here rather than
543 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
544 		 */
545 
546 		/*
547 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
548 		 * we need udpiphdr for IPsec processing so we do that later.
549 		 */
550 		/*
551 		 * Locate pcb(s) for datagram.
552 		 */
553 		TAILQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
554 			inp = (struct inpcb *)inph;
555 			if (inp->inp_af != AF_INET)
556 				continue;
557 
558 			if (inp->inp_lport != *dport)
559 				continue;
560 			if (!in_nullhost(inp->inp_laddr)) {
561 				if (!in_hosteq(inp->inp_laddr, *dst4))
562 					continue;
563 			}
564 			if (!in_nullhost(inp->inp_faddr)) {
565 				if (!in_hosteq(inp->inp_faddr, *src4) ||
566 				    inp->inp_fport != *sport)
567 					continue;
568 			}
569 
570 			udp4_sendup(m, off, (struct sockaddr *)src,
571 				inp->inp_socket);
572 			rcvcnt++;
573 
574 			/*
575 			 * Don't look for additional matches if this one does
576 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
577 			 * socket options set.  This heuristic avoids searching
578 			 * through all pcbs in the common case of a non-shared
579 			 * port.  It assumes that an application will never
580 			 * clear these options after setting them.
581 			 */
582 			if ((inp->inp_socket->so_options &
583 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
584 				break;
585 		}
586 	} else {
587 		/*
588 		 * Locate pcb for datagram.
589 		 */
590 		inp = in_pcblookup_connect(&udbtable, *src4, *sport, *dst4,
591 		    *dport, 0);
592 		if (inp == 0) {
593 			UDP_STATINC(UDP_STAT_PCBHASHMISS);
594 			inp = in_pcblookup_bind(&udbtable, *dst4, *dport);
595 			if (inp == 0)
596 				return rcvcnt;
597 		}
598 
599 #ifdef IPSEC
600 		/* Handle ESP over UDP */
601 		if (inp->inp_flags & INP_ESPINUDP_ALL) {
602 			struct sockaddr *sa = (struct sockaddr *)src;
603 
604 			switch(udp4_espinudp(mp, off, sa, inp->inp_socket)) {
605 			case -1: 	/* Error, m was freeed */
606 				rcvcnt = -1;
607 				goto bad;
608 				break;
609 
610 			case 1:		/* ESP over UDP */
611 				rcvcnt++;
612 				goto bad;
613 				break;
614 
615 			case 0: 	/* plain UDP */
616 			default: 	/* Unexpected */
617 				/*
618 				 * Normal UDP processing will take place
619 				 * m may have changed.
620 				 */
621 				m = *mp;
622 				break;
623 			}
624 		}
625 #endif
626 
627 		/*
628 		 * Check the minimum TTL for socket.
629 		 */
630 		if (mtod(m, struct ip *)->ip_ttl < inp->inp_ip_minttl)
631 			goto bad;
632 
633 		udp4_sendup(m, off, (struct sockaddr *)src, inp->inp_socket);
634 		rcvcnt++;
635 	}
636 
637 bad:
638 	return rcvcnt;
639 }
640 #endif
641 
642 #ifdef INET
643 /*
644  * Notify a udp user of an asynchronous error;
645  * just wake up so that he can collect error status.
646  */
647 static void
648 udp_notify(struct inpcb *inp, int errno)
649 {
650 	inp->inp_socket->so_error = errno;
651 	sorwakeup(inp->inp_socket);
652 	sowwakeup(inp->inp_socket);
653 }
654 
655 void *
656 udp_ctlinput(int cmd, const struct sockaddr *sa, void *v)
657 {
658 	struct ip *ip = v;
659 	struct udphdr *uh;
660 	void (*notify)(struct inpcb *, int) = udp_notify;
661 	int errno;
662 
663 	if (sa->sa_family != AF_INET
664 	 || sa->sa_len != sizeof(struct sockaddr_in))
665 		return NULL;
666 	if ((unsigned)cmd >= PRC_NCMDS)
667 		return NULL;
668 	errno = inetctlerrmap[cmd];
669 	if (PRC_IS_REDIRECT(cmd))
670 		notify = in_rtchange, ip = 0;
671 	else if (cmd == PRC_HOSTDEAD)
672 		ip = 0;
673 	else if (errno == 0)
674 		return NULL;
675 	if (ip) {
676 		uh = (struct udphdr *)((char *)ip + (ip->ip_hl << 2));
677 		in_pcbnotify(&udbtable, satocsin(sa)->sin_addr, uh->uh_dport,
678 		    ip->ip_src, uh->uh_sport, errno, notify);
679 
680 		/* XXX mapped address case */
681 	} else
682 		in_pcbnotifyall(&udbtable, satocsin(sa)->sin_addr, errno,
683 		    notify);
684 	return NULL;
685 }
686 
687 int
688 udp_ctloutput(int op, struct socket *so, struct sockopt *sopt)
689 {
690 	int s;
691 	int error = 0;
692 	struct inpcb *inp;
693 	int family;
694 	int optval;
695 
696 	family = so->so_proto->pr_domain->dom_family;
697 
698 	s = splsoftnet();
699 	switch (family) {
700 #ifdef INET
701 	case PF_INET:
702 		if (sopt->sopt_level != IPPROTO_UDP) {
703 			error = ip_ctloutput(op, so, sopt);
704 			goto end;
705 		}
706 		break;
707 #endif
708 #ifdef INET6
709 	case PF_INET6:
710 		if (sopt->sopt_level != IPPROTO_UDP) {
711 			error = ip6_ctloutput(op, so, sopt);
712 			goto end;
713 		}
714 		break;
715 #endif
716 	default:
717 		error = EAFNOSUPPORT;
718 		goto end;
719 	}
720 
721 
722 	switch (op) {
723 	case PRCO_SETOPT:
724 		inp = sotoinpcb(so);
725 
726 		switch (sopt->sopt_name) {
727 		case UDP_ENCAP:
728 			error = sockopt_getint(sopt, &optval);
729 			if (error)
730 				break;
731 
732 			switch(optval) {
733 			case 0:
734 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
735 				break;
736 
737 			case UDP_ENCAP_ESPINUDP:
738 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
739 				inp->inp_flags |= INP_ESPINUDP;
740 				break;
741 
742 			case UDP_ENCAP_ESPINUDP_NON_IKE:
743 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
744 				inp->inp_flags |= INP_ESPINUDP_NON_IKE;
745 				break;
746 			default:
747 				error = EINVAL;
748 				break;
749 			}
750 			break;
751 
752 		default:
753 			error = ENOPROTOOPT;
754 			break;
755 		}
756 		break;
757 
758 	default:
759 		error = EINVAL;
760 		break;
761 	}
762 
763 end:
764 	splx(s);
765 	return error;
766 }
767 
768 int
769 udp_output(struct mbuf *m, struct inpcb *inp, struct mbuf *control,
770     struct lwp *l)
771 {
772 	struct udpiphdr *ui;
773 	struct route *ro;
774 	struct ip_pktopts pktopts;
775 	kauth_cred_t cred;
776 	int len = m->m_pkthdr.len;
777 	int error, flags = 0;
778 
779 	MCLAIM(m, &udp_tx_mowner);
780 
781 	/*
782 	 * Calculate data length and get a mbuf
783 	 * for UDP and IP headers.
784 	 */
785 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
786 	if (m == 0) {
787 		error = ENOBUFS;
788 		goto release;
789 	}
790 
791 	/*
792 	 * Compute the packet length of the IP header, and
793 	 * punt if the length looks bogus.
794 	 */
795 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
796 		error = EMSGSIZE;
797 		goto release;
798 	}
799 
800 	if (l == NULL)
801 		cred = NULL;
802 	else
803 		cred = l->l_cred;
804 
805 	/* Setup IP outgoing packet options */
806 	memset(&pktopts, 0, sizeof(pktopts));
807 	error = ip_setpktopts(control, &pktopts, &flags, inp, cred);
808 	if (error != 0)
809 		goto release;
810 
811 	if (control != NULL) {
812 		m_freem(control);
813 		control = NULL;
814 	}
815 
816 	/*
817 	 * Fill in mbuf with extended UDP header
818 	 * and addresses and length put into network format.
819 	 */
820 	ui = mtod(m, struct udpiphdr *);
821 	ui->ui_pr = IPPROTO_UDP;
822 	ui->ui_src = pktopts.ippo_laddr.sin_addr;
823 	ui->ui_dst = inp->inp_faddr;
824 	ui->ui_sport = inp->inp_lport;
825 	ui->ui_dport = inp->inp_fport;
826 	ui->ui_ulen = htons((u_int16_t)len + sizeof(struct udphdr));
827 
828 	ro = &inp->inp_route;
829 
830 	/*
831 	 * Set up checksum and output datagram.
832 	 */
833 	if (udpcksum) {
834 		/*
835 		 * XXX Cache pseudo-header checksum part for
836 		 * XXX "connected" UDP sockets.
837 		 */
838 		ui->ui_sum = in_cksum_phdr(ui->ui_src.s_addr,
839 		    ui->ui_dst.s_addr, htons((u_int16_t)len +
840 		    sizeof(struct udphdr) + IPPROTO_UDP));
841 		m->m_pkthdr.csum_flags = M_CSUM_UDPv4;
842 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
843 	} else
844 		ui->ui_sum = 0;
845 	((struct ip *)ui)->ip_len = htons(sizeof (struct udpiphdr) + len);
846 	((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;	/* XXX */
847 	((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;	/* XXX */
848 	UDP_STATINC(UDP_STAT_OPACKETS);
849 
850 	flags |= inp->inp_socket->so_options & (SO_DONTROUTE|SO_BROADCAST);
851 	return ip_output(m, inp->inp_options, ro, flags, pktopts.ippo_imo, inp);
852 
853  release:
854 	if (control != NULL)
855 		m_freem(control);
856 	m_freem(m);
857 	return error;
858 }
859 
860 static int
861 udp_attach(struct socket *so, int proto)
862 {
863 	struct inpcb *inp;
864 	int error;
865 
866 	KASSERT(sotoinpcb(so) == NULL);
867 
868 	/* Assign the lock (must happen even if we will error out). */
869 	sosetlock(so);
870 
871 #ifdef MBUFTRACE
872 	so->so_mowner = &udp_mowner;
873 	so->so_rcv.sb_mowner = &udp_rx_mowner;
874 	so->so_snd.sb_mowner = &udp_tx_mowner;
875 #endif
876 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
877 		error = soreserve(so, udp_sendspace, udp_recvspace);
878 		if (error) {
879 			return error;
880 		}
881 	}
882 
883 	error = in_pcballoc(so, &udbtable);
884 	if (error) {
885 		return error;
886 	}
887 	inp = sotoinpcb(so);
888 	inp->inp_ip.ip_ttl = ip_defttl;
889 	KASSERT(solocked(so));
890 
891 	return error;
892 }
893 
894 static void
895 udp_detach(struct socket *so)
896 {
897 	struct inpcb *inp;
898 
899 	KASSERT(solocked(so));
900 	inp = sotoinpcb(so);
901 	KASSERT(inp != NULL);
902 	in_pcbdetach(inp);
903 }
904 
905 static int
906 udp_accept(struct socket *so, struct sockaddr *nam)
907 {
908 	KASSERT(solocked(so));
909 
910 	panic("udp_accept");
911 
912 	return EOPNOTSUPP;
913 }
914 
915 static int
916 udp_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
917 {
918 	struct inpcb *inp = sotoinpcb(so);
919 	struct sockaddr_in *sin = (struct sockaddr_in *)nam;
920 	int error = 0;
921 	int s;
922 
923 	KASSERT(solocked(so));
924 	KASSERT(inp != NULL);
925 	KASSERT(nam != NULL);
926 
927 	s = splsoftnet();
928 	error = in_pcbbind(inp, sin, l);
929 	splx(s);
930 
931 	return error;
932 }
933 
934 static int
935 udp_listen(struct socket *so, struct lwp *l)
936 {
937 	KASSERT(solocked(so));
938 
939 	return EOPNOTSUPP;
940 }
941 
942 static int
943 udp_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
944 {
945 	struct inpcb *inp = sotoinpcb(so);
946 	int error = 0;
947 	int s;
948 
949 	KASSERT(solocked(so));
950 	KASSERT(inp != NULL);
951 	KASSERT(nam != NULL);
952 
953 	s = splsoftnet();
954 	error = in_pcbconnect(inp, (struct sockaddr_in *)nam, l);
955 	if (! error)
956 		soisconnected(so);
957 	splx(s);
958 	return error;
959 }
960 
961 static int
962 udp_connect2(struct socket *so, struct socket *so2)
963 {
964 	KASSERT(solocked(so));
965 
966 	return EOPNOTSUPP;
967 }
968 
969 static int
970 udp_disconnect(struct socket *so)
971 {
972 	struct inpcb *inp = sotoinpcb(so);
973 	int s;
974 
975 	KASSERT(solocked(so));
976 	KASSERT(inp != NULL);
977 
978 	s = splsoftnet();
979 	/*soisdisconnected(so);*/
980 	so->so_state &= ~SS_ISCONNECTED;	/* XXX */
981 	in_pcbdisconnect(inp);
982 	inp->inp_laddr = zeroin_addr;		/* XXX */
983 	in_pcbstate(inp, INP_BOUND);		/* XXX */
984 	splx(s);
985 
986 	return 0;
987 }
988 
989 static int
990 udp_shutdown(struct socket *so)
991 {
992 	int s;
993 
994 	KASSERT(solocked(so));
995 
996 	s = splsoftnet();
997 	socantsendmore(so);
998 	splx(s);
999 
1000 	return 0;
1001 }
1002 
1003 static int
1004 udp_abort(struct socket *so)
1005 {
1006 	KASSERT(solocked(so));
1007 
1008 	panic("udp_abort");
1009 
1010 	return EOPNOTSUPP;
1011 }
1012 
1013 static int
1014 udp_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp)
1015 {
1016 	return in_control(so, cmd, nam, ifp);
1017 }
1018 
1019 static int
1020 udp_stat(struct socket *so, struct stat *ub)
1021 {
1022 	KASSERT(solocked(so));
1023 
1024 	/* stat: don't bother with a blocksize. */
1025 	return 0;
1026 }
1027 
1028 static int
1029 udp_peeraddr(struct socket *so, struct sockaddr *nam)
1030 {
1031 	int s;
1032 
1033 	KASSERT(solocked(so));
1034 	KASSERT(sotoinpcb(so) != NULL);
1035 	KASSERT(nam != NULL);
1036 
1037 	s = splsoftnet();
1038 	in_setpeeraddr(sotoinpcb(so), (struct sockaddr_in *)nam);
1039 	splx(s);
1040 
1041 	return 0;
1042 }
1043 
1044 static int
1045 udp_sockaddr(struct socket *so, struct sockaddr *nam)
1046 {
1047 	int s;
1048 
1049 	KASSERT(solocked(so));
1050 	KASSERT(sotoinpcb(so) != NULL);
1051 	KASSERT(nam != NULL);
1052 
1053 	s = splsoftnet();
1054 	in_setsockaddr(sotoinpcb(so), (struct sockaddr_in *)nam);
1055 	splx(s);
1056 
1057 	return 0;
1058 }
1059 
1060 static int
1061 udp_rcvd(struct socket *so, int flags, struct lwp *l)
1062 {
1063 	KASSERT(solocked(so));
1064 
1065 	return EOPNOTSUPP;
1066 }
1067 
1068 static int
1069 udp_recvoob(struct socket *so, struct mbuf *m, int flags)
1070 {
1071 	KASSERT(solocked(so));
1072 
1073 	return EOPNOTSUPP;
1074 }
1075 
1076 static int
1077 udp_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
1078     struct mbuf *control, struct lwp *l)
1079 {
1080 	struct inpcb *inp = sotoinpcb(so);
1081 	int error = 0;
1082 	struct in_addr laddr;			/* XXX */
1083 	int s;
1084 
1085 	KASSERT(solocked(so));
1086 	KASSERT(inp != NULL);
1087 	KASSERT(m != NULL);
1088 
1089 	memset(&laddr, 0, sizeof laddr);
1090 
1091 	s = splsoftnet();
1092 	if (nam) {
1093 		laddr = inp->inp_laddr;		/* XXX */
1094 		if ((so->so_state & SS_ISCONNECTED) != 0) {
1095 			error = EISCONN;
1096 			goto die;
1097 		}
1098 		error = in_pcbconnect(inp, (struct sockaddr_in *)nam, l);
1099 		if (error)
1100 			goto die;
1101 	} else {
1102 		if ((so->so_state & SS_ISCONNECTED) == 0) {
1103 			error = ENOTCONN;
1104 			goto die;
1105 		}
1106 	}
1107 	error = udp_output(m, inp, control, l);
1108 	m = NULL;
1109 	control = NULL;
1110 	if (nam) {
1111 		in_pcbdisconnect(inp);
1112 		inp->inp_laddr = laddr;		/* XXX */
1113 		in_pcbstate(inp, INP_BOUND);	/* XXX */
1114 	}
1115   die:
1116 	if (m != NULL)
1117 		m_freem(m);
1118 	if (control != NULL)
1119 		m_freem(control);
1120 
1121 	splx(s);
1122 	return error;
1123 }
1124 
1125 static int
1126 udp_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
1127 {
1128 	KASSERT(solocked(so));
1129 
1130 	m_freem(m);
1131 	m_freem(control);
1132 
1133 	return EOPNOTSUPP;
1134 }
1135 
1136 static int
1137 udp_purgeif(struct socket *so, struct ifnet *ifp)
1138 {
1139 	int s;
1140 
1141 	s = splsoftnet();
1142 	mutex_enter(softnet_lock);
1143 	in_pcbpurgeif0(&udbtable, ifp);
1144 #ifdef NET_MPSAFE
1145 	mutex_exit(softnet_lock);
1146 #endif
1147 	in_purgeif(ifp);
1148 #ifdef NET_MPSAFE
1149 	mutex_enter(softnet_lock);
1150 #endif
1151 	in_pcbpurgeif(&udbtable, ifp);
1152 	mutex_exit(softnet_lock);
1153 	splx(s);
1154 
1155 	return 0;
1156 }
1157 
1158 static int
1159 sysctl_net_inet_udp_stats(SYSCTLFN_ARGS)
1160 {
1161 
1162 	return (NETSTAT_SYSCTL(udpstat_percpu, UDP_NSTATS));
1163 }
1164 
1165 /*
1166  * Sysctl for udp variables.
1167  */
1168 static void
1169 sysctl_net_inet_udp_setup(struct sysctllog **clog)
1170 {
1171 
1172 	sysctl_createv(clog, 0, NULL, NULL,
1173 		       CTLFLAG_PERMANENT,
1174 		       CTLTYPE_NODE, "inet", NULL,
1175 		       NULL, 0, NULL, 0,
1176 		       CTL_NET, PF_INET, CTL_EOL);
1177 	sysctl_createv(clog, 0, NULL, NULL,
1178 		       CTLFLAG_PERMANENT,
1179 		       CTLTYPE_NODE, "udp",
1180 		       SYSCTL_DESCR("UDPv4 related settings"),
1181 		       NULL, 0, NULL, 0,
1182 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_EOL);
1183 
1184 	sysctl_createv(clog, 0, NULL, NULL,
1185 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1186 		       CTLTYPE_INT, "checksum",
1187 		       SYSCTL_DESCR("Compute UDP checksums"),
1188 		       NULL, 0, &udpcksum, 0,
1189 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_CHECKSUM,
1190 		       CTL_EOL);
1191 	sysctl_createv(clog, 0, NULL, NULL,
1192 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1193 		       CTLTYPE_INT, "sendspace",
1194 		       SYSCTL_DESCR("Default UDP send buffer size"),
1195 		       NULL, 0, &udp_sendspace, 0,
1196 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_SENDSPACE,
1197 		       CTL_EOL);
1198 	sysctl_createv(clog, 0, NULL, NULL,
1199 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1200 		       CTLTYPE_INT, "recvspace",
1201 		       SYSCTL_DESCR("Default UDP receive buffer size"),
1202 		       NULL, 0, &udp_recvspace, 0,
1203 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_RECVSPACE,
1204 		       CTL_EOL);
1205 	sysctl_createv(clog, 0, NULL, NULL,
1206 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1207 		       CTLTYPE_INT, "do_loopback_cksum",
1208 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
1209 		       NULL, 0, &udp_do_loopback_cksum, 0,
1210 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_LOOPBACKCKSUM,
1211 		       CTL_EOL);
1212 	sysctl_createv(clog, 0, NULL, NULL,
1213 		       CTLFLAG_PERMANENT,
1214 		       CTLTYPE_STRUCT, "pcblist",
1215 		       SYSCTL_DESCR("UDP protocol control block list"),
1216 		       sysctl_inpcblist, 0, &udbtable, 0,
1217 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_CREATE,
1218 		       CTL_EOL);
1219 	sysctl_createv(clog, 0, NULL, NULL,
1220 		       CTLFLAG_PERMANENT,
1221 		       CTLTYPE_STRUCT, "stats",
1222 		       SYSCTL_DESCR("UDP statistics"),
1223 		       sysctl_net_inet_udp_stats, 0, NULL, 0,
1224 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_STATS,
1225 		       CTL_EOL);
1226 }
1227 #endif
1228 
1229 void
1230 udp_statinc(u_int stat)
1231 {
1232 
1233 	KASSERT(stat < UDP_NSTATS);
1234 	UDP_STATINC(stat);
1235 }
1236 
1237 #if defined(INET) && defined(IPSEC)
1238 /*
1239  * Returns:
1240  * 1 if the packet was processed
1241  * 0 if normal UDP processing should take place
1242  * -1 if an error occurent and m was freed
1243  */
1244 static int
1245 udp4_espinudp(struct mbuf **mp, int off, struct sockaddr *src,
1246     struct socket *so)
1247 {
1248 	size_t len;
1249 	void *data;
1250 	struct inpcb *inp;
1251 	size_t skip = 0;
1252 	size_t minlen;
1253 	size_t iphdrlen;
1254 	struct ip *ip;
1255 	struct m_tag *tag;
1256 	struct udphdr *udphdr;
1257 	u_int16_t sport, dport;
1258 	struct mbuf *m = *mp;
1259 
1260 	/*
1261 	 * Collapse the mbuf chain if the first mbuf is too short
1262 	 * The longest case is: UDP + non ESP marker + ESP
1263 	 */
1264 	minlen = off + sizeof(u_int64_t) + sizeof(struct esp);
1265 	if (minlen > m->m_pkthdr.len)
1266 		minlen = m->m_pkthdr.len;
1267 
1268 	if (m->m_len < minlen) {
1269 		if ((*mp = m_pullup(m, minlen)) == NULL) {
1270 			printf("udp4_espinudp: m_pullup failed\n");
1271 			return -1;
1272 		}
1273 		m = *mp;
1274 	}
1275 
1276 	len = m->m_len - off;
1277 	data = mtod(m, char *) + off;
1278 	inp = sotoinpcb(so);
1279 
1280 	/* Ignore keepalive packets */
1281 	if ((len == 1) && (*(unsigned char *)data == 0xff)) {
1282 		m_free(m);
1283 		*mp = NULL; /* avoid any further processiong by caller ... */
1284 		return 1;
1285 	}
1286 
1287 	/*
1288 	 * Check that the payload is long enough to hold
1289 	 * an ESP header and compute the length of encapsulation
1290 	 * header to remove
1291 	 */
1292 	if (inp->inp_flags & INP_ESPINUDP) {
1293 		u_int32_t *st = (u_int32_t *)data;
1294 
1295 		if ((len <= sizeof(struct esp)) || (*st == 0))
1296 			return 0; /* Normal UDP processing */
1297 
1298 		skip = sizeof(struct udphdr);
1299 	}
1300 
1301 	if (inp->inp_flags & INP_ESPINUDP_NON_IKE) {
1302 		u_int32_t *st = (u_int32_t *)data;
1303 
1304 		if ((len <= sizeof(u_int64_t) + sizeof(struct esp))
1305 		    || ((st[0] | st[1]) != 0))
1306 			return 0; /* Normal UDP processing */
1307 
1308 		skip = sizeof(struct udphdr) + sizeof(u_int64_t);
1309 	}
1310 
1311 	/*
1312 	 * Get the UDP ports. They are handled in network
1313 	 * order everywhere in IPSEC_NAT_T code.
1314 	 */
1315 	udphdr = (struct udphdr *)((char *)data - skip);
1316 	sport = udphdr->uh_sport;
1317 	dport = udphdr->uh_dport;
1318 
1319 	/*
1320 	 * Remove the UDP header (and possibly the non ESP marker)
1321 	 * IP header lendth is iphdrlen
1322 	 * Before:
1323 	 *   <--- off --->
1324 	 *   +----+------+-----+
1325 	 *   | IP |  UDP | ESP |
1326 	 *   +----+------+-----+
1327 	 *        <-skip->
1328 	 * After:
1329 	 *          +----+-----+
1330 	 *          | IP | ESP |
1331 	 *          +----+-----+
1332 	 *   <-skip->
1333 	 */
1334 	iphdrlen = off - sizeof(struct udphdr);
1335 	memmove(mtod(m, char *) + skip, mtod(m, void *), iphdrlen);
1336 	m_adj(m, skip);
1337 
1338 	ip = mtod(m, struct ip *);
1339 	ip->ip_len = htons(ntohs(ip->ip_len) - skip);
1340 	ip->ip_p = IPPROTO_ESP;
1341 
1342 	/*
1343 	 * We have modified the packet - it is now ESP, so we should not
1344 	 * return to UDP processing ...
1345 	 *
1346 	 * Add a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember
1347 	 * the source UDP port. This is required if we want
1348 	 * to select the right SPD for multiple hosts behind
1349 	 * same NAT
1350 	 */
1351 	if ((tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS,
1352 	    sizeof(sport) + sizeof(dport), M_DONTWAIT)) == NULL) {
1353 		printf("udp4_espinudp: m_tag_get failed\n");
1354 		m_freem(m);
1355 		return -1;
1356 	}
1357 	((u_int16_t *)(tag + 1))[0] = sport;
1358 	((u_int16_t *)(tag + 1))[1] = dport;
1359 	m_tag_prepend(m, tag);
1360 
1361 	if (ipsec_used)
1362 		ipsec4_common_input(m, iphdrlen, IPPROTO_ESP);
1363 	/* XXX: else */
1364 
1365 	/* We handled it, it shouldn't be handled by UDP */
1366 	*mp = NULL; /* avoid free by caller ... */
1367 	return 1;
1368 }
1369 #endif
1370 
1371 PR_WRAP_USRREQS(udp)
1372 #define	udp_attach	udp_attach_wrapper
1373 #define	udp_detach	udp_detach_wrapper
1374 #define	udp_accept	udp_accept_wrapper
1375 #define	udp_bind	udp_bind_wrapper
1376 #define	udp_listen	udp_listen_wrapper
1377 #define	udp_connect	udp_connect_wrapper
1378 #define	udp_connect2	udp_connect2_wrapper
1379 #define	udp_disconnect	udp_disconnect_wrapper
1380 #define	udp_shutdown	udp_shutdown_wrapper
1381 #define	udp_abort	udp_abort_wrapper
1382 #define	udp_ioctl	udp_ioctl_wrapper
1383 #define	udp_stat	udp_stat_wrapper
1384 #define	udp_peeraddr	udp_peeraddr_wrapper
1385 #define	udp_sockaddr	udp_sockaddr_wrapper
1386 #define	udp_rcvd	udp_rcvd_wrapper
1387 #define	udp_recvoob	udp_recvoob_wrapper
1388 #define	udp_send	udp_send_wrapper
1389 #define	udp_sendoob	udp_sendoob_wrapper
1390 #define	udp_purgeif	udp_purgeif_wrapper
1391 
1392 const struct pr_usrreqs udp_usrreqs = {
1393 	.pr_attach	= udp_attach,
1394 	.pr_detach	= udp_detach,
1395 	.pr_accept	= udp_accept,
1396 	.pr_bind	= udp_bind,
1397 	.pr_listen	= udp_listen,
1398 	.pr_connect	= udp_connect,
1399 	.pr_connect2	= udp_connect2,
1400 	.pr_disconnect	= udp_disconnect,
1401 	.pr_shutdown	= udp_shutdown,
1402 	.pr_abort	= udp_abort,
1403 	.pr_ioctl	= udp_ioctl,
1404 	.pr_stat	= udp_stat,
1405 	.pr_peeraddr	= udp_peeraddr,
1406 	.pr_sockaddr	= udp_sockaddr,
1407 	.pr_rcvd	= udp_rcvd,
1408 	.pr_recvoob	= udp_recvoob,
1409 	.pr_send	= udp_send,
1410 	.pr_sendoob	= udp_sendoob,
1411 	.pr_purgeif	= udp_purgeif,
1412 };
1413