xref: /netbsd-src/sys/netinet/udp_usrreq.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: udp_usrreq.c,v 1.145 2005/12/11 12:24:58 christos 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 #include <sys/cdefs.h>
64 __KERNEL_RCSID(0, "$NetBSD: udp_usrreq.c,v 1.145 2005/12/11 12:24:58 christos Exp $");
65 
66 #include "opt_inet.h"
67 #include "opt_ipsec.h"
68 #include "opt_inet_csum.h"
69 #include "opt_ipkdb.h"
70 #include "opt_mbuftrace.h"
71 
72 #include <sys/param.h>
73 #include <sys/malloc.h>
74 #include <sys/mbuf.h>
75 #include <sys/protosw.h>
76 #include <sys/socket.h>
77 #include <sys/socketvar.h>
78 #include <sys/errno.h>
79 #include <sys/stat.h>
80 #include <sys/systm.h>
81 #include <sys/proc.h>
82 #include <sys/domain.h>
83 #include <sys/sysctl.h>
84 
85 #include <net/if.h>
86 #include <net/route.h>
87 
88 #include <netinet/in.h>
89 #include <netinet/in_systm.h>
90 #include <netinet/in_var.h>
91 #include <netinet/ip.h>
92 #include <netinet/in_pcb.h>
93 #include <netinet/ip_var.h>
94 #include <netinet/ip_icmp.h>
95 #include <netinet/udp.h>
96 #include <netinet/udp_var.h>
97 
98 #ifdef IPSEC_NAT_T
99 #include <netinet6/ipsec.h>
100 #include <netinet6/esp.h>
101 #endif
102 
103 #ifdef INET6
104 #include <netinet/ip6.h>
105 #include <netinet/icmp6.h>
106 #include <netinet6/ip6_var.h>
107 #include <netinet6/in6_pcb.h>
108 #include <netinet6/udp6_var.h>
109 #endif
110 
111 #ifndef INET6
112 /* always need ip6.h for IP6_EXTHDR_GET */
113 #include <netinet/ip6.h>
114 #endif
115 
116 #include "faith.h"
117 #if defined(NFAITH) && NFAITH > 0
118 #include <net/if_faith.h>
119 #endif
120 
121 #include <machine/stdarg.h>
122 
123 #ifdef FAST_IPSEC
124 #include <netipsec/ipsec.h>
125 #include <netipsec/ipsec_var.h>			/* XXX ipsecstat namespace */
126 #ifdef INET6
127 #include <netipsec/ipsec6.h>
128 #endif
129 #endif	/* FAST_IPSEC*/
130 
131 #ifdef IPSEC
132 #include <netinet6/ipsec.h>
133 #include <netkey/key.h>
134 #endif /*IPSEC*/
135 
136 #ifdef IPKDB
137 #include <ipkdb/ipkdb.h>
138 #endif
139 
140 /*
141  * UDP protocol implementation.
142  * Per RFC 768, August, 1980.
143  */
144 #ifndef	COMPAT_42
145 int	udpcksum = 1;
146 #else
147 int	udpcksum = 0;		/* XXX */
148 #endif
149 int	udp_do_loopback_cksum = 0;
150 
151 struct	inpcbtable udbtable;
152 struct	udpstat udpstat;
153 
154 #ifdef INET
155 #ifdef IPSEC_NAT_T
156 static int udp4_espinudp (struct mbuf **, int, struct sockaddr *,
157 	struct socket *);
158 #endif
159 static void udp4_sendup (struct mbuf *, int, struct sockaddr *,
160 	struct socket *);
161 static int udp4_realinput (struct sockaddr_in *, struct sockaddr_in *,
162 	struct mbuf **, int);
163 static int udp4_input_checksum(struct mbuf *, const struct udphdr *, int, int);
164 #endif
165 #ifdef INET6
166 static void udp6_sendup (struct mbuf *, int, struct sockaddr *,
167 	struct socket *);
168 static int udp6_realinput (int, struct sockaddr_in6 *,
169 	struct sockaddr_in6 *, struct mbuf *, int);
170 static int udp6_input_checksum(struct mbuf *, const struct udphdr *, int, int);
171 #endif
172 #ifdef INET
173 static	void udp_notify (struct inpcb *, int);
174 #endif
175 
176 #ifndef UDBHASHSIZE
177 #define	UDBHASHSIZE	128
178 #endif
179 int	udbhashsize = UDBHASHSIZE;
180 
181 #ifdef MBUFTRACE
182 struct mowner udp_mowner = { "udp" };
183 struct mowner udp_rx_mowner = { "udp", "rx" };
184 struct mowner udp_tx_mowner = { "udp", "tx" };
185 #endif
186 
187 #ifdef UDP_CSUM_COUNTERS
188 #include <sys/device.h>
189 
190 #if defined(INET)
191 struct evcnt udp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
192     NULL, "udp", "hwcsum bad");
193 struct evcnt udp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
194     NULL, "udp", "hwcsum ok");
195 struct evcnt udp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
196     NULL, "udp", "hwcsum data");
197 struct evcnt udp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
198     NULL, "udp", "swcsum");
199 
200 EVCNT_ATTACH_STATIC(udp_hwcsum_bad);
201 EVCNT_ATTACH_STATIC(udp_hwcsum_ok);
202 EVCNT_ATTACH_STATIC(udp_hwcsum_data);
203 EVCNT_ATTACH_STATIC(udp_swcsum);
204 #endif /* defined(INET) */
205 
206 #if defined(INET6)
207 struct evcnt udp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
208     NULL, "udp6", "hwcsum bad");
209 struct evcnt udp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
210     NULL, "udp6", "hwcsum ok");
211 struct evcnt udp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
212     NULL, "udp6", "hwcsum data");
213 struct evcnt udp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
214     NULL, "udp6", "swcsum");
215 
216 EVCNT_ATTACH_STATIC(udp6_hwcsum_bad);
217 EVCNT_ATTACH_STATIC(udp6_hwcsum_ok);
218 EVCNT_ATTACH_STATIC(udp6_hwcsum_data);
219 EVCNT_ATTACH_STATIC(udp6_swcsum);
220 #endif /* defined(INET6) */
221 
222 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
223 
224 #else
225 
226 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
227 
228 #endif /* UDP_CSUM_COUNTERS */
229 
230 void
231 udp_init(void)
232 {
233 
234 	in_pcbinit(&udbtable, udbhashsize, udbhashsize);
235 
236 	MOWNER_ATTACH(&udp_tx_mowner);
237 	MOWNER_ATTACH(&udp_rx_mowner);
238 	MOWNER_ATTACH(&udp_mowner);
239 }
240 
241 /*
242  * Checksum extended UDP header and data.
243  */
244 
245 int
246 udp_input_checksum(int af, struct mbuf *m, const struct udphdr *uh,
247     int iphlen, int len)
248 {
249 
250 	switch (af) {
251 #ifdef INET
252 	case AF_INET:
253 		return udp4_input_checksum(m, uh, iphlen, len);
254 #endif
255 #ifdef INET6
256 	case AF_INET6:
257 		return udp6_input_checksum(m, uh, iphlen, len);
258 #endif
259 	}
260 #ifdef DIAGNOSTIC
261 	panic("udp_input_checksum: unknown af %d", af);
262 #endif
263 	/* NOTREACHED */
264 	return -1;
265 }
266 
267 #ifdef INET
268 
269 /*
270  * Checksum extended UDP header and data.
271  */
272 
273 static int
274 udp4_input_checksum(struct mbuf *m, const struct udphdr *uh,
275     int iphlen, int len)
276 {
277 
278 	/*
279 	 * XXX it's better to record and check if this mbuf is
280 	 * already checked.
281 	 */
282 
283 	if (uh->uh_sum == 0)
284 		return 0;
285 
286 	switch (m->m_pkthdr.csum_flags &
287 	    ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_UDPv4) |
288 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
289 	case M_CSUM_UDPv4|M_CSUM_TCP_UDP_BAD:
290 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_bad);
291 		goto badcsum;
292 
293 	case M_CSUM_UDPv4|M_CSUM_DATA: {
294 		u_int32_t hw_csum = m->m_pkthdr.csum_data;
295 
296 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_data);
297 		if (m->m_pkthdr.csum_flags & M_CSUM_NO_PSEUDOHDR) {
298 			const struct ip *ip =
299 			    mtod(m, const struct ip *);
300 
301 			hw_csum = in_cksum_phdr(ip->ip_src.s_addr,
302 			    ip->ip_dst.s_addr,
303 			    htons(hw_csum + len + IPPROTO_UDP));
304 		}
305 		if ((hw_csum ^ 0xffff) != 0)
306 			goto badcsum;
307 		break;
308 	}
309 
310 	case M_CSUM_UDPv4:
311 		/* Checksum was okay. */
312 		UDP_CSUM_COUNTER_INCR(&udp_hwcsum_ok);
313 		break;
314 
315 	default:
316 		/*
317 		 * Need to compute it ourselves.  Maybe skip checksum
318 		 * on loopback interfaces.
319 		 */
320 		if (__predict_true(!(m->m_pkthdr.rcvif->if_flags &
321 				     IFF_LOOPBACK) ||
322 				   udp_do_loopback_cksum)) {
323 			UDP_CSUM_COUNTER_INCR(&udp_swcsum);
324 			if (in4_cksum(m, IPPROTO_UDP, iphlen, len) != 0)
325 				goto badcsum;
326 		}
327 		break;
328 	}
329 
330 	return 0;
331 
332 badcsum:
333 	udpstat.udps_badsum++;
334 	return -1;
335 }
336 
337 void
338 udp_input(struct mbuf *m, ...)
339 {
340 	va_list ap;
341 	struct sockaddr_in src, dst;
342 	struct ip *ip;
343 	struct udphdr *uh;
344 	int iphlen;
345 	int len;
346 	int n;
347 	u_int16_t ip_len;
348 
349 	va_start(ap, m);
350 	iphlen = va_arg(ap, int);
351 	(void)va_arg(ap, int);		/* ignore value, advance ap */
352 	va_end(ap);
353 
354 	MCLAIM(m, &udp_rx_mowner);
355 	udpstat.udps_ipackets++;
356 
357 	/*
358 	 * Get IP and UDP header together in first mbuf.
359 	 */
360 	ip = mtod(m, struct ip *);
361 	IP6_EXTHDR_GET(uh, struct udphdr *, m, iphlen, sizeof(struct udphdr));
362 	if (uh == NULL) {
363 		udpstat.udps_hdrops++;
364 		return;
365 	}
366 	KASSERT(UDP_HDR_ALIGNED_P(uh));
367 
368 	/* destination port of 0 is illegal, based on RFC768. */
369 	if (uh->uh_dport == 0)
370 		goto bad;
371 
372 	/*
373 	 * Make mbuf data length reflect UDP length.
374 	 * If not enough data to reflect UDP length, drop.
375 	 */
376 	ip_len = ntohs(ip->ip_len);
377 	len = ntohs((u_int16_t)uh->uh_ulen);
378 	if (ip_len != iphlen + len) {
379 		if (ip_len < iphlen + len || len < sizeof(struct udphdr)) {
380 			udpstat.udps_badlen++;
381 			goto bad;
382 		}
383 		m_adj(m, iphlen + len - ip_len);
384 	}
385 
386 	/*
387 	 * Checksum extended UDP header and data.
388 	 */
389 	if (udp4_input_checksum(m, uh, iphlen, len))
390 		goto badcsum;
391 
392 	/* construct source and dst sockaddrs. */
393 	bzero(&src, sizeof(src));
394 	src.sin_family = AF_INET;
395 	src.sin_len = sizeof(struct sockaddr_in);
396 	bcopy(&ip->ip_src, &src.sin_addr, sizeof(src.sin_addr));
397 	src.sin_port = uh->uh_sport;
398 	bzero(&dst, sizeof(dst));
399 	dst.sin_family = AF_INET;
400 	dst.sin_len = sizeof(struct sockaddr_in);
401 	bcopy(&ip->ip_dst, &dst.sin_addr, sizeof(dst.sin_addr));
402 	dst.sin_port = uh->uh_dport;
403 
404 	if ((n = udp4_realinput(&src, &dst, &m, iphlen)) == -1) {
405 		udpstat.udps_hdrops++;
406 		return;
407 	}
408 #ifdef INET6
409 	if (IN_MULTICAST(ip->ip_dst.s_addr) || n == 0) {
410 		struct sockaddr_in6 src6, dst6;
411 
412 		bzero(&src6, sizeof(src6));
413 		src6.sin6_family = AF_INET6;
414 		src6.sin6_len = sizeof(struct sockaddr_in6);
415 		src6.sin6_addr.s6_addr[10] = src6.sin6_addr.s6_addr[11] = 0xff;
416 		bcopy(&ip->ip_src, &src6.sin6_addr.s6_addr[12],
417 			sizeof(ip->ip_src));
418 		src6.sin6_port = uh->uh_sport;
419 		bzero(&dst6, sizeof(dst6));
420 		dst6.sin6_family = AF_INET6;
421 		dst6.sin6_len = sizeof(struct sockaddr_in6);
422 		dst6.sin6_addr.s6_addr[10] = dst6.sin6_addr.s6_addr[11] = 0xff;
423 		bcopy(&ip->ip_dst, &dst6.sin6_addr.s6_addr[12],
424 			sizeof(ip->ip_dst));
425 		dst6.sin6_port = uh->uh_dport;
426 
427 		n += udp6_realinput(AF_INET, &src6, &dst6, m, iphlen);
428 	}
429 #endif
430 
431 	if (n == 0) {
432 		if (m->m_flags & (M_BCAST | M_MCAST)) {
433 			udpstat.udps_noportbcast++;
434 			goto bad;
435 		}
436 		udpstat.udps_noport++;
437 #ifdef IPKDB
438 		if (checkipkdb(&ip->ip_src, uh->uh_sport, uh->uh_dport,
439 				m, iphlen + sizeof(struct udphdr),
440 				m->m_pkthdr.len - iphlen - sizeof(struct udphdr))) {
441 			/*
442 			 * It was a debugger connect packet,
443 			 * just drop it now
444 			 */
445 			goto bad;
446 		}
447 #endif
448 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
449 		m = NULL;
450 	}
451 
452 bad:
453 	if (m)
454 		m_freem(m);
455 	return;
456 
457 badcsum:
458 	m_freem(m);
459 }
460 #endif
461 
462 #ifdef INET6
463 static int
464 udp6_input_checksum(struct mbuf *m, const struct udphdr *uh, int off, int len)
465 {
466 
467 	/*
468 	 * XXX it's better to record and check if this mbuf is
469 	 * already checked.
470 	 */
471 
472 	if (__predict_false((m->m_flags & M_LOOP) && !udp_do_loopback_cksum)) {
473 		goto good;
474 	}
475 	if (uh->uh_sum == 0) {
476 		udp6stat.udp6s_nosum++;
477 		goto bad;
478 	}
479 
480 	switch (m->m_pkthdr.csum_flags &
481 	    ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_UDPv6) |
482 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
483 	case M_CSUM_UDPv6|M_CSUM_TCP_UDP_BAD:
484 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_bad);
485 		udp6stat.udp6s_badsum++;
486 		goto bad;
487 
488 #if 0 /* notyet */
489 	case M_CSUM_UDPv6|M_CSUM_DATA:
490 #endif
491 
492 	case M_CSUM_UDPv6:
493 		/* Checksum was okay. */
494 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_ok);
495 		break;
496 
497 	default:
498 		/*
499 		 * Need to compute it ourselves.  Maybe skip checksum
500 		 * on loopback interfaces.
501 		 */
502 		UDP_CSUM_COUNTER_INCR(&udp6_swcsum);
503 		if (in6_cksum(m, IPPROTO_UDP, off, len) != 0) {
504 			udp6stat.udp6s_badsum++;
505 			goto bad;
506 		}
507 	}
508 
509 good:
510 	return 0;
511 bad:
512 	return -1;
513 }
514 
515 int
516 udp6_input(struct mbuf **mp, int *offp, int proto)
517 {
518 	struct mbuf *m = *mp;
519 	int off = *offp;
520 	struct sockaddr_in6 src, dst;
521 	struct ip6_hdr *ip6;
522 	struct udphdr *uh;
523 	u_int32_t plen, ulen;
524 
525 	ip6 = mtod(m, struct ip6_hdr *);
526 
527 #if defined(NFAITH) && 0 < NFAITH
528 	if (faithprefix(&ip6->ip6_dst)) {
529 		/* send icmp6 host unreach? */
530 		m_freem(m);
531 		return IPPROTO_DONE;
532 	}
533 #endif
534 
535 	udp6stat.udp6s_ipackets++;
536 
537 	/* check for jumbogram is done in ip6_input.  we can trust pkthdr.len */
538 	plen = m->m_pkthdr.len - off;
539 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
540 	if (uh == NULL) {
541 		ip6stat.ip6s_tooshort++;
542 		return IPPROTO_DONE;
543 	}
544 	KASSERT(UDP_HDR_ALIGNED_P(uh));
545 	ulen = ntohs((u_short)uh->uh_ulen);
546 	/*
547 	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
548 	 * iff payload length > 0xffff.
549 	 */
550 	if (ulen == 0 && plen > 0xffff)
551 		ulen = plen;
552 
553 	if (plen != ulen) {
554 		udp6stat.udp6s_badlen++;
555 		goto bad;
556 	}
557 
558 	/* destination port of 0 is illegal, based on RFC768. */
559 	if (uh->uh_dport == 0)
560 		goto bad;
561 
562 	/* Be proactive about malicious use of IPv4 mapped address */
563 	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
564 	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
565 		/* XXX stat */
566 		goto bad;
567 	}
568 
569 	/*
570 	 * Checksum extended UDP header and data.  Maybe skip checksum
571 	 * on loopback interfaces.
572 	 */
573 	if (udp6_input_checksum(m, uh, off, ulen))
574 		goto bad;
575 
576 	/*
577 	 * Construct source and dst sockaddrs.
578 	 * Note that ifindex (s6_addr16[1]) is already filled.
579 	 */
580 	bzero(&src, sizeof(src));
581 	src.sin6_family = AF_INET6;
582 	src.sin6_len = sizeof(struct sockaddr_in6);
583 	/* KAME hack: recover scopeid */
584 	(void)in6_recoverscope(&src, &ip6->ip6_src, m->m_pkthdr.rcvif);
585 	src.sin6_port = uh->uh_sport;
586 	bzero(&dst, sizeof(dst));
587 	dst.sin6_family = AF_INET6;
588 	dst.sin6_len = sizeof(struct sockaddr_in6);
589 	/* KAME hack: recover scopeid */
590 	(void)in6_recoverscope(&dst, &ip6->ip6_dst, m->m_pkthdr.rcvif);
591 	dst.sin6_port = uh->uh_dport;
592 
593 	if (udp6_realinput(AF_INET6, &src, &dst, m, off) == 0) {
594 		if (m->m_flags & M_MCAST) {
595 			udp6stat.udp6s_noportmcast++;
596 			goto bad;
597 		}
598 		udp6stat.udp6s_noport++;
599 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
600 		m = NULL;
601 	}
602 
603 bad:
604 	if (m)
605 		m_freem(m);
606 	return IPPROTO_DONE;
607 }
608 #endif
609 
610 #ifdef INET
611 static void
612 udp4_sendup(struct mbuf *m, int off /* offset of data portion */,
613 	struct sockaddr *src, struct socket *so)
614 {
615 	struct mbuf *opts = NULL;
616 	struct mbuf *n;
617 	struct inpcb *inp = NULL;
618 
619 	if (!so)
620 		return;
621 	switch (so->so_proto->pr_domain->dom_family) {
622 	case AF_INET:
623 		inp = sotoinpcb(so);
624 		break;
625 #ifdef INET6
626 	case AF_INET6:
627 		break;
628 #endif
629 	default:
630 		return;
631 	}
632 
633 #if defined(IPSEC) || defined(FAST_IPSEC)
634 	/* check AH/ESP integrity. */
635 	if (so != NULL && ipsec4_in_reject_so(m, so)) {
636 		ipsecstat.in_polvio++;
637 		if ((n = m_copy(m, 0, M_COPYALL)) != NULL)
638 			icmp_error(n, ICMP_UNREACH, ICMP_UNREACH_ADMIN_PROHIBIT,
639 			    0, 0);
640 		return;
641 	}
642 #endif /*IPSEC*/
643 
644 	if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
645 		if (inp && (inp->inp_flags & INP_CONTROLOPTS
646 			 || so->so_options & SO_TIMESTAMP)) {
647 			struct ip *ip = mtod(n, struct ip *);
648 			ip_savecontrol(inp, &opts, ip, n);
649 		}
650 
651 		m_adj(n, off);
652 		if (sbappendaddr(&so->so_rcv, src, n,
653 				opts) == 0) {
654 			m_freem(n);
655 			if (opts)
656 				m_freem(opts);
657 			so->so_rcv.sb_overflowed++;
658 			udpstat.udps_fullsock++;
659 		} else
660 			sorwakeup(so);
661 	}
662 }
663 #endif
664 
665 #ifdef INET6
666 static void
667 udp6_sendup(struct mbuf *m, int off /* offset of data portion */,
668 	struct sockaddr *src, struct socket *so)
669 {
670 	struct mbuf *opts = NULL;
671 	struct mbuf *n;
672 	struct in6pcb *in6p = NULL;
673 
674 	if (!so)
675 		return;
676 	if (so->so_proto->pr_domain->dom_family != AF_INET6)
677 		return;
678 	in6p = sotoin6pcb(so);
679 
680 #if defined(IPSEC) || defined(FAST_IPSEC)
681 	/* check AH/ESP integrity. */
682 	if (so != NULL && ipsec6_in_reject_so(m, so)) {
683 		ipsec6stat.in_polvio++;
684 		if ((n = m_copy(m, 0, M_COPYALL)) != NULL)
685 			icmp6_error(n, ICMP6_DST_UNREACH,
686 			    ICMP6_DST_UNREACH_ADMIN, 0);
687 		return;
688 	}
689 #endif /*IPSEC*/
690 
691 	if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
692 		if (in6p && (in6p->in6p_flags & IN6P_CONTROLOPTS
693 			  || in6p->in6p_socket->so_options & SO_TIMESTAMP)) {
694 			struct ip6_hdr *ip6 = mtod(n, struct ip6_hdr *);
695 			ip6_savecontrol(in6p, &opts, ip6, n);
696 		}
697 
698 		m_adj(n, off);
699 		if (sbappendaddr(&so->so_rcv, src, n, opts) == 0) {
700 			m_freem(n);
701 			if (opts)
702 				m_freem(opts);
703 			so->so_rcv.sb_overflowed++;
704 			udp6stat.udp6s_fullsock++;
705 		} else
706 			sorwakeup(so);
707 	}
708 }
709 #endif
710 
711 #ifdef INET
712 static int
713 udp4_realinput(struct sockaddr_in *src, struct sockaddr_in *dst,
714 	struct mbuf **mp, int off /* offset of udphdr */)
715 {
716 	u_int16_t *sport, *dport;
717 	int rcvcnt;
718 	struct in_addr *src4, *dst4;
719 	struct inpcb_hdr *inph;
720 	struct inpcb *inp;
721 	struct mbuf *m = *mp;
722 
723 	rcvcnt = 0;
724 	off += sizeof(struct udphdr);	/* now, offset of payload */
725 
726 	if (src->sin_family != AF_INET || dst->sin_family != AF_INET)
727 		goto bad;
728 
729 	src4 = &src->sin_addr;
730 	sport = &src->sin_port;
731 	dst4 = &dst->sin_addr;
732 	dport = &dst->sin_port;
733 
734 	if (IN_MULTICAST(dst4->s_addr) ||
735 	    in_broadcast(*dst4, m->m_pkthdr.rcvif)) {
736 		/*
737 		 * Deliver a multicast or broadcast datagram to *all* sockets
738 		 * for which the local and remote addresses and ports match
739 		 * those of the incoming datagram.  This allows more than
740 		 * one process to receive multi/broadcasts on the same port.
741 		 * (This really ought to be done for unicast datagrams as
742 		 * well, but that would cause problems with existing
743 		 * applications that open both address-specific sockets and
744 		 * a wildcard socket listening to the same port -- they would
745 		 * end up receiving duplicates of every unicast datagram.
746 		 * Those applications open the multiple sockets to overcome an
747 		 * inadequacy of the UDP socket interface, but for backwards
748 		 * compatibility we avoid the problem here rather than
749 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
750 		 */
751 
752 		/*
753 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
754 		 * we need udpiphdr for IPsec processing so we do that later.
755 		 */
756 		/*
757 		 * Locate pcb(s) for datagram.
758 		 */
759 		CIRCLEQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
760 			inp = (struct inpcb *)inph;
761 			if (inp->inp_af != AF_INET)
762 				continue;
763 
764 			if (inp->inp_lport != *dport)
765 				continue;
766 			if (!in_nullhost(inp->inp_laddr)) {
767 				if (!in_hosteq(inp->inp_laddr, *dst4))
768 					continue;
769 			}
770 			if (!in_nullhost(inp->inp_faddr)) {
771 				if (!in_hosteq(inp->inp_faddr, *src4) ||
772 				    inp->inp_fport != *sport)
773 					continue;
774 			}
775 
776 			udp4_sendup(m, off, (struct sockaddr *)src,
777 				inp->inp_socket);
778 			rcvcnt++;
779 
780 			/*
781 			 * Don't look for additional matches if this one does
782 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
783 			 * socket options set.  This heuristic avoids searching
784 			 * through all pcbs in the common case of a non-shared
785 			 * port.  It assumes that an application will never
786 			 * clear these options after setting them.
787 			 */
788 			if ((inp->inp_socket->so_options &
789 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
790 				break;
791 		}
792 	} else {
793 		/*
794 		 * Locate pcb for datagram.
795 		 */
796 		inp = in_pcblookup_connect(&udbtable, *src4, *sport, *dst4, *dport);
797 		if (inp == 0) {
798 			++udpstat.udps_pcbhashmiss;
799 			inp = in_pcblookup_bind(&udbtable, *dst4, *dport);
800 			if (inp == 0)
801 				return rcvcnt;
802 		}
803 
804 #ifdef IPSEC_NAT_T
805 		/* Handle ESP over UDP */
806 		if (inp->inp_flags & INP_ESPINUDP_ALL) {
807 			struct sockaddr *sa = (struct sockaddr *)src;
808 
809 			switch(udp4_espinudp(mp, off, sa, inp->inp_socket)) {
810 			case -1: 	/* Error, m was freeed */
811 				rcvcnt = -1;
812 				goto bad;
813 				break;
814 
815 			case 1:		/* ESP over UDP */
816 				rcvcnt++;
817 				goto bad;
818 				break;
819 
820 			case 0: 	/* plain UDP */
821 			default: 	/* Unexpected */
822 				/*
823 				 * Normal UDP processing will take place
824 				 * m may have changed.
825 				 */
826 				m = *mp;
827 				break;
828 			}
829 		}
830 #endif
831 
832 		udp4_sendup(m, off, (struct sockaddr *)src, inp->inp_socket);
833 		rcvcnt++;
834 	}
835 
836 bad:
837 	return rcvcnt;
838 }
839 #endif
840 
841 #ifdef INET6
842 static int
843 udp6_realinput(int af, struct sockaddr_in6 *src, struct sockaddr_in6 *dst,
844 	struct mbuf *m, int off)
845 {
846 	u_int16_t sport, dport;
847 	int rcvcnt;
848 	struct in6_addr src6, dst6;
849 	const struct in_addr *dst4;
850 	struct inpcb_hdr *inph;
851 	struct in6pcb *in6p;
852 
853 	rcvcnt = 0;
854 	off += sizeof(struct udphdr);	/* now, offset of payload */
855 
856 	if (af != AF_INET && af != AF_INET6)
857 		goto bad;
858 	if (src->sin6_family != AF_INET6 || dst->sin6_family != AF_INET6)
859 		goto bad;
860 
861 	in6_embedscope(&src6, src, NULL, NULL);
862 	sport = src->sin6_port;
863 	in6_embedscope(&dst6, dst, NULL, NULL);
864 	dport = dst->sin6_port;
865 	dst4 = (struct in_addr *)&dst->sin6_addr.s6_addr[12];
866 
867 	if (IN6_IS_ADDR_MULTICAST(&dst6) ||
868 	    (af == AF_INET && IN_MULTICAST(dst4->s_addr))) {
869 		/*
870 		 * Deliver a multicast or broadcast datagram to *all* sockets
871 		 * for which the local and remote addresses and ports match
872 		 * those of the incoming datagram.  This allows more than
873 		 * one process to receive multi/broadcasts on the same port.
874 		 * (This really ought to be done for unicast datagrams as
875 		 * well, but that would cause problems with existing
876 		 * applications that open both address-specific sockets and
877 		 * a wildcard socket listening to the same port -- they would
878 		 * end up receiving duplicates of every unicast datagram.
879 		 * Those applications open the multiple sockets to overcome an
880 		 * inadequacy of the UDP socket interface, but for backwards
881 		 * compatibility we avoid the problem here rather than
882 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
883 		 */
884 
885 		/*
886 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
887 		 * we need udpiphdr for IPsec processing so we do that later.
888 		 */
889 		/*
890 		 * Locate pcb(s) for datagram.
891 		 */
892 		CIRCLEQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
893 			in6p = (struct in6pcb *)inph;
894 			if (in6p->in6p_af != AF_INET6)
895 				continue;
896 
897 			if (in6p->in6p_lport != dport)
898 				continue;
899 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
900 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &dst6))
901 					continue;
902 			} else {
903 				if (IN6_IS_ADDR_V4MAPPED(&dst6) &&
904 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
905 					continue;
906 			}
907 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
908 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
909 				    &src6) || in6p->in6p_fport != sport)
910 					continue;
911 			} else {
912 				if (IN6_IS_ADDR_V4MAPPED(&src6) &&
913 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
914 					continue;
915 			}
916 
917 			udp6_sendup(m, off, (struct sockaddr *)src,
918 				in6p->in6p_socket);
919 			rcvcnt++;
920 
921 			/*
922 			 * Don't look for additional matches if this one does
923 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
924 			 * socket options set.  This heuristic avoids searching
925 			 * through all pcbs in the common case of a non-shared
926 			 * port.  It assumes that an application will never
927 			 * clear these options after setting them.
928 			 */
929 			if ((in6p->in6p_socket->so_options &
930 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
931 				break;
932 		}
933 	} else {
934 		/*
935 		 * Locate pcb for datagram.
936 		 */
937 		in6p = in6_pcblookup_connect(&udbtable, &src6, sport,
938 		    &dst6, dport, 0);
939 		if (in6p == 0) {
940 			++udpstat.udps_pcbhashmiss;
941 			in6p = in6_pcblookup_bind(&udbtable, &dst6, dport, 0);
942 			if (in6p == 0)
943 				return rcvcnt;
944 		}
945 
946 		udp6_sendup(m, off, (struct sockaddr *)src, in6p->in6p_socket);
947 		rcvcnt++;
948 	}
949 
950 bad:
951 	return rcvcnt;
952 }
953 #endif
954 
955 #ifdef INET
956 /*
957  * Notify a udp user of an asynchronous error;
958  * just wake up so that he can collect error status.
959  */
960 static void
961 udp_notify(struct inpcb *inp, int errno)
962 {
963 	inp->inp_socket->so_error = errno;
964 	sorwakeup(inp->inp_socket);
965 	sowwakeup(inp->inp_socket);
966 }
967 
968 void *
969 udp_ctlinput(int cmd, struct sockaddr *sa, void *v)
970 {
971 	struct ip *ip = v;
972 	struct udphdr *uh;
973 	void (*notify)(struct inpcb *, int) = udp_notify;
974 	int errno;
975 
976 	if (sa->sa_family != AF_INET
977 	 || sa->sa_len != sizeof(struct sockaddr_in))
978 		return NULL;
979 	if ((unsigned)cmd >= PRC_NCMDS)
980 		return NULL;
981 	errno = inetctlerrmap[cmd];
982 	if (PRC_IS_REDIRECT(cmd))
983 		notify = in_rtchange, ip = 0;
984 	else if (cmd == PRC_HOSTDEAD)
985 		ip = 0;
986 	else if (errno == 0)
987 		return NULL;
988 	if (ip) {
989 		uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
990 		in_pcbnotify(&udbtable, satosin(sa)->sin_addr, uh->uh_dport,
991 		    ip->ip_src, uh->uh_sport, errno, notify);
992 
993 		/* XXX mapped address case */
994 	} else
995 		in_pcbnotifyall(&udbtable, satosin(sa)->sin_addr, errno,
996 		    notify);
997 	return NULL;
998 }
999 
1000 int
1001 udp_ctloutput(op, so, level, optname, mp)
1002 	int op;
1003 	struct socket *so;
1004 	int level, optname;
1005 	struct mbuf **mp;
1006 {
1007 	int s;
1008 	int error = 0;
1009 	struct mbuf *m;
1010 	struct inpcb *inp;
1011 	int family;
1012 
1013 	family = so->so_proto->pr_domain->dom_family;
1014 
1015 	s = splsoftnet();
1016 	switch (family) {
1017 #ifdef INET
1018 	case PF_INET:
1019 		if (level != IPPROTO_UDP) {
1020 			error = ip_ctloutput(op, so, level, optname, mp);
1021 			goto end;
1022 		}
1023 		break;
1024 #endif
1025 #ifdef INET6
1026 	case PF_INET6:
1027 		if (level != IPPROTO_UDP) {
1028 			error = ip6_ctloutput(op, so, level, optname, mp);
1029 			goto end;
1030 		}
1031 		break;
1032 #endif
1033 	default:
1034 		error = EAFNOSUPPORT;
1035 		goto end;
1036 		break;
1037 	}
1038 
1039 
1040 	switch (op) {
1041 	case PRCO_SETOPT:
1042 		m = *mp;
1043 		inp = sotoinpcb(so);
1044 
1045 		switch (optname) {
1046 		case UDP_ENCAP:
1047 			if (m == NULL || m->m_len < sizeof (int)) {
1048 				error = EINVAL;
1049 				goto end;
1050 			}
1051 
1052 			switch(*mtod(m, int *)) {
1053 #ifdef IPSEC_NAT_T
1054 			case 0:
1055 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
1056 				break;
1057 
1058 			case UDP_ENCAP_ESPINUDP:
1059 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
1060 				inp->inp_flags |= INP_ESPINUDP;
1061 				break;
1062 
1063 			case UDP_ENCAP_ESPINUDP_NON_IKE:
1064 				inp->inp_flags &= ~INP_ESPINUDP_ALL;
1065 				inp->inp_flags |= INP_ESPINUDP_NON_IKE;
1066 				break;
1067 #endif
1068 			default:
1069 				error = EINVAL;
1070 				goto end;
1071 				break;
1072 			}
1073 			break;
1074 
1075 		default:
1076 			error = ENOPROTOOPT;
1077 			goto end;
1078 			break;
1079 		}
1080 		break;
1081 
1082 	default:
1083 		error = EINVAL;
1084 		goto end;
1085 		break;
1086 	}
1087 
1088 end:
1089 	splx(s);
1090 	return error;
1091 }
1092 
1093 
1094 int
1095 udp_output(struct mbuf *m, ...)
1096 {
1097 	struct inpcb *inp;
1098 	struct udpiphdr *ui;
1099 	struct route *ro;
1100 	int len = m->m_pkthdr.len;
1101 	int error = 0;
1102 	va_list ap;
1103 
1104 	MCLAIM(m, &udp_tx_mowner);
1105 	va_start(ap, m);
1106 	inp = va_arg(ap, struct inpcb *);
1107 	va_end(ap);
1108 
1109 	/*
1110 	 * Calculate data length and get a mbuf
1111 	 * for UDP and IP headers.
1112 	 */
1113 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
1114 	if (m == 0) {
1115 		error = ENOBUFS;
1116 		goto release;
1117 	}
1118 
1119 	/*
1120 	 * Compute the packet length of the IP header, and
1121 	 * punt if the length looks bogus.
1122 	 */
1123 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1124 		error = EMSGSIZE;
1125 		goto release;
1126 	}
1127 
1128 	/*
1129 	 * Fill in mbuf with extended UDP header
1130 	 * and addresses and length put into network format.
1131 	 */
1132 	ui = mtod(m, struct udpiphdr *);
1133 	ui->ui_pr = IPPROTO_UDP;
1134 	ui->ui_src = inp->inp_laddr;
1135 	ui->ui_dst = inp->inp_faddr;
1136 	ui->ui_sport = inp->inp_lport;
1137 	ui->ui_dport = inp->inp_fport;
1138 	ui->ui_ulen = htons((u_int16_t)len + sizeof(struct udphdr));
1139 
1140 	ro = &inp->inp_route;
1141 
1142 	/*
1143 	 * Set up checksum and output datagram.
1144 	 */
1145 	if (udpcksum) {
1146 		/*
1147 		 * XXX Cache pseudo-header checksum part for
1148 		 * XXX "connected" UDP sockets.
1149 		 */
1150 		ui->ui_sum = in_cksum_phdr(ui->ui_src.s_addr,
1151 		    ui->ui_dst.s_addr, htons((u_int16_t)len +
1152 		    sizeof(struct udphdr) + IPPROTO_UDP));
1153 		m->m_pkthdr.csum_flags = M_CSUM_UDPv4;
1154 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1155 	} else
1156 		ui->ui_sum = 0;
1157 	((struct ip *)ui)->ip_len = htons(sizeof (struct udpiphdr) + len);
1158 	((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;	/* XXX */
1159 	((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;	/* XXX */
1160 	udpstat.udps_opackets++;
1161 
1162 	return (ip_output(m, inp->inp_options, ro,
1163 	    inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST),
1164 	    inp->inp_moptions, inp->inp_socket));
1165 
1166 release:
1167 	m_freem(m);
1168 	return (error);
1169 }
1170 
1171 int	udp_sendspace = 9216;		/* really max datagram size */
1172 int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
1173 					/* 40 1K datagrams */
1174 
1175 /*ARGSUSED*/
1176 int
1177 udp_usrreq(struct socket *so, int req, struct mbuf *m, struct mbuf *nam,
1178 	struct mbuf *control, struct lwp *l)
1179 {
1180 	struct inpcb *inp;
1181 	struct proc *p;
1182 	int s;
1183 	int error = 0;
1184 
1185 	p = l ? l->l_proc : NULL;
1186 	if (req == PRU_CONTROL)
1187 		return (in_control(so, (long)m, (caddr_t)nam,
1188 		    (struct ifnet *)control, p));
1189 
1190 	if (req == PRU_PURGEIF) {
1191 		in_pcbpurgeif0(&udbtable, (struct ifnet *)control);
1192 		in_purgeif((struct ifnet *)control);
1193 		in_pcbpurgeif(&udbtable, (struct ifnet *)control);
1194 		return (0);
1195 	}
1196 
1197 	s = splsoftnet();
1198 	inp = sotoinpcb(so);
1199 #ifdef DIAGNOSTIC
1200 	if (req != PRU_SEND && req != PRU_SENDOOB && control)
1201 		panic("udp_usrreq: unexpected control mbuf");
1202 #endif
1203 	if (inp == 0 && req != PRU_ATTACH) {
1204 		error = EINVAL;
1205 		goto release;
1206 	}
1207 
1208 	/*
1209 	 * Note: need to block udp_input while changing
1210 	 * the udp pcb queue and/or pcb addresses.
1211 	 */
1212 	switch (req) {
1213 
1214 	case PRU_ATTACH:
1215 		if (inp != 0) {
1216 			error = EISCONN;
1217 			break;
1218 		}
1219 #ifdef MBUFTRACE
1220 		so->so_mowner = &udp_mowner;
1221 		so->so_rcv.sb_mowner = &udp_rx_mowner;
1222 		so->so_snd.sb_mowner = &udp_tx_mowner;
1223 #endif
1224 		if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1225 			error = soreserve(so, udp_sendspace, udp_recvspace);
1226 			if (error)
1227 				break;
1228 		}
1229 		error = in_pcballoc(so, &udbtable);
1230 		if (error)
1231 			break;
1232 		inp = sotoinpcb(so);
1233 		inp->inp_ip.ip_ttl = ip_defttl;
1234 		break;
1235 
1236 	case PRU_DETACH:
1237 		in_pcbdetach(inp);
1238 		break;
1239 
1240 	case PRU_BIND:
1241 		error = in_pcbbind(inp, nam, p);
1242 		break;
1243 
1244 	case PRU_LISTEN:
1245 		error = EOPNOTSUPP;
1246 		break;
1247 
1248 	case PRU_CONNECT:
1249 		error = in_pcbconnect(inp, nam, p);
1250 		if (error)
1251 			break;
1252 		soisconnected(so);
1253 		break;
1254 
1255 	case PRU_CONNECT2:
1256 		error = EOPNOTSUPP;
1257 		break;
1258 
1259 	case PRU_DISCONNECT:
1260 		/*soisdisconnected(so);*/
1261 		so->so_state &= ~SS_ISCONNECTED;	/* XXX */
1262 		in_pcbdisconnect(inp);
1263 		inp->inp_laddr = zeroin_addr;		/* XXX */
1264 		in_pcbstate(inp, INP_BOUND);		/* XXX */
1265 		break;
1266 
1267 	case PRU_SHUTDOWN:
1268 		socantsendmore(so);
1269 		break;
1270 
1271 	case PRU_RCVD:
1272 		error = EOPNOTSUPP;
1273 		break;
1274 
1275 	case PRU_SEND:
1276 		if (control && control->m_len) {
1277 			m_freem(control);
1278 			m_freem(m);
1279 			error = EINVAL;
1280 			break;
1281 		}
1282 	{
1283 		struct in_addr laddr;			/* XXX */
1284 
1285 		if (nam) {
1286 			laddr = inp->inp_laddr;		/* XXX */
1287 			if ((so->so_state & SS_ISCONNECTED) != 0) {
1288 				error = EISCONN;
1289 				goto die;
1290 			}
1291 			error = in_pcbconnect(inp, nam, p);
1292 			if (error)
1293 				goto die;
1294 		} else {
1295 			if ((so->so_state & SS_ISCONNECTED) == 0) {
1296 				error = ENOTCONN;
1297 				goto die;
1298 			}
1299 		}
1300 		error = udp_output(m, inp);
1301 		m = NULL;
1302 		if (nam) {
1303 			in_pcbdisconnect(inp);
1304 			inp->inp_laddr = laddr;		/* XXX */
1305 			in_pcbstate(inp, INP_BOUND);	/* XXX */
1306 		}
1307 	  die:
1308 		if (m)
1309 			m_freem(m);
1310 	}
1311 		break;
1312 
1313 	case PRU_SENSE:
1314 		/*
1315 		 * stat: don't bother with a blocksize.
1316 		 */
1317 		splx(s);
1318 		return (0);
1319 
1320 	case PRU_RCVOOB:
1321 		error =  EOPNOTSUPP;
1322 		break;
1323 
1324 	case PRU_SENDOOB:
1325 		m_freem(control);
1326 		m_freem(m);
1327 		error =  EOPNOTSUPP;
1328 		break;
1329 
1330 	case PRU_SOCKADDR:
1331 		in_setsockaddr(inp, nam);
1332 		break;
1333 
1334 	case PRU_PEERADDR:
1335 		in_setpeeraddr(inp, nam);
1336 		break;
1337 
1338 	default:
1339 		panic("udp_usrreq");
1340 	}
1341 
1342 release:
1343 	splx(s);
1344 	return (error);
1345 }
1346 
1347 /*
1348  * Sysctl for udp variables.
1349  */
1350 SYSCTL_SETUP(sysctl_net_inet_udp_setup, "sysctl net.inet.udp subtree setup")
1351 {
1352 
1353 	sysctl_createv(clog, 0, NULL, NULL,
1354 		       CTLFLAG_PERMANENT,
1355 		       CTLTYPE_NODE, "net", NULL,
1356 		       NULL, 0, NULL, 0,
1357 		       CTL_NET, CTL_EOL);
1358 	sysctl_createv(clog, 0, NULL, NULL,
1359 		       CTLFLAG_PERMANENT,
1360 		       CTLTYPE_NODE, "inet", NULL,
1361 		       NULL, 0, NULL, 0,
1362 		       CTL_NET, PF_INET, CTL_EOL);
1363 	sysctl_createv(clog, 0, NULL, NULL,
1364 		       CTLFLAG_PERMANENT,
1365 		       CTLTYPE_NODE, "udp",
1366 		       SYSCTL_DESCR("UDPv4 related settings"),
1367 		       NULL, 0, NULL, 0,
1368 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_EOL);
1369 
1370 	sysctl_createv(clog, 0, NULL, NULL,
1371 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1372 		       CTLTYPE_INT, "checksum",
1373 		       SYSCTL_DESCR("Compute UDP checksums"),
1374 		       NULL, 0, &udpcksum, 0,
1375 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_CHECKSUM,
1376 		       CTL_EOL);
1377 	sysctl_createv(clog, 0, NULL, NULL,
1378 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1379 		       CTLTYPE_INT, "sendspace",
1380 		       SYSCTL_DESCR("Default UDP send buffer size"),
1381 		       NULL, 0, &udp_sendspace, 0,
1382 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_SENDSPACE,
1383 		       CTL_EOL);
1384 	sysctl_createv(clog, 0, NULL, NULL,
1385 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1386 		       CTLTYPE_INT, "recvspace",
1387 		       SYSCTL_DESCR("Default UDP receive buffer size"),
1388 		       NULL, 0, &udp_recvspace, 0,
1389 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_RECVSPACE,
1390 		       CTL_EOL);
1391 	sysctl_createv(clog, 0, NULL, NULL,
1392 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1393 		       CTLTYPE_INT, "do_loopback_cksum",
1394 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
1395 		       NULL, 0, &udp_do_loopback_cksum, 0,
1396 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_LOOPBACKCKSUM,
1397 		       CTL_EOL);
1398 	sysctl_createv(clog, 0, NULL, NULL,
1399 		       CTLFLAG_PERMANENT,
1400 		       CTLTYPE_STRUCT, "pcblist",
1401 		       SYSCTL_DESCR("UDP protocol control block list"),
1402 		       sysctl_inpcblist, 0, &udbtable, 0,
1403 		       CTL_NET, PF_INET, IPPROTO_UDP, CTL_CREATE,
1404 		       CTL_EOL);
1405 	sysctl_createv(clog, 0, NULL, NULL,
1406 		       CTLFLAG_PERMANENT,
1407 		       CTLTYPE_STRUCT, "stats",
1408 		       SYSCTL_DESCR("UDP statistics"),
1409 		       NULL, 0, &udpstat, sizeof(udpstat),
1410 		       CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_STATS,
1411 		       CTL_EOL);
1412 }
1413 #endif
1414 
1415 #if (defined INET && defined IPSEC_NAT_T)
1416 /*
1417  * Returns:
1418  * 1 if the packet was processed
1419  * 0 if normal UDP processing should take place
1420  * -1 if an error occurent and m was freed
1421  */
1422 static int
1423 udp4_espinudp(mp, off, src, so)
1424 	struct mbuf **mp;
1425 	int off;
1426 	struct sockaddr *src;
1427 	struct socket *so;
1428 {
1429 	size_t len;
1430 	caddr_t data;
1431 	struct inpcb *inp;
1432 	size_t skip = 0;
1433 	size_t minlen;
1434 	size_t iphdrlen;
1435 	struct ip *ip;
1436 	struct mbuf *n;
1437 	struct m_tag *tag;
1438 	struct udphdr *udphdr;
1439 	u_int16_t sport, dport;
1440 	struct mbuf *m = *mp;
1441 
1442 	/*
1443 	 * Collapse the mbuf chain if the first mbuf is too short
1444 	 * The longest case is: UDP + non ESP marker + ESP
1445 	 */
1446 	minlen = off + sizeof(u_int64_t) + sizeof(struct esp);
1447 	if (minlen > m->m_pkthdr.len)
1448 		minlen = m->m_pkthdr.len;
1449 
1450 	if (m->m_len < minlen) {
1451 		if ((*mp = m_pullup(m, minlen)) == NULL) {
1452 			printf("udp4_espinudp: m_pullup failed\n");
1453 			return -1;
1454 		}
1455 		m = *mp;
1456 	}
1457 
1458 	len = m->m_len - off;
1459 	data = mtod(m, caddr_t) + off;
1460 	inp = sotoinpcb(so);
1461 
1462 	/* Ignore keepalive packets */
1463 	if ((len == 1) && (data[0] == '\xff')) {
1464 		return 1;
1465 	}
1466 
1467 	/*
1468 	 * Check that the payload is long enough to hold
1469 	 * an ESP header and compute the length of encapsulation
1470 	 * header to remove
1471 	 */
1472 	if (inp->inp_flags & INP_ESPINUDP) {
1473 		u_int32_t *st = (u_int32_t *)data;
1474 
1475 		if ((len <= sizeof(struct esp)) || (*st == 0))
1476 			return 0; /* Normal UDP processing */
1477 
1478 		skip = sizeof(struct udphdr);
1479 	}
1480 
1481 	if (inp->inp_flags & INP_ESPINUDP_NON_IKE) {
1482 		u_int32_t *st = (u_int32_t *)data;
1483 
1484 		if ((len <= sizeof(u_int64_t) + sizeof(struct esp))
1485 		    || ((st[0] | st[1]) != 0))
1486 			return 0; /* Normal UDP processing */
1487 
1488 		skip = sizeof(struct udphdr) + sizeof(u_int64_t);
1489 	}
1490 
1491 	/*
1492 	 * Get the UDP ports. They are handled in network
1493 	 * order everywhere in IPSEC_NAT_T code.
1494 	 */
1495 	udphdr = (struct udphdr *)(data - skip);
1496 	sport = udphdr->uh_sport;
1497 	dport = udphdr->uh_dport;
1498 
1499 	/*
1500 	 * Remove the UDP header (and possibly the non ESP marker)
1501 	 * IP header lendth is iphdrlen
1502 	 * Before:
1503 	 *   <--- off --->
1504 	 *   +----+------+-----+
1505 	 *   | IP |  UDP | ESP |
1506 	 *   +----+------+-----+
1507 	 *        <-skip->
1508 	 * After:
1509 	 *          +----+-----+
1510 	 *          | IP | ESP |
1511 	 *          +----+-----+
1512 	 *   <-skip->
1513 	 */
1514 	iphdrlen = off - sizeof(struct udphdr);
1515 	memmove(mtod(m, caddr_t) + skip, mtod(m, caddr_t), iphdrlen);
1516 	m_adj(m, skip);
1517 
1518 	ip = mtod(m, struct ip *);
1519 	ip->ip_len = htons(ntohs(ip->ip_len) - skip);
1520 	ip->ip_p = IPPROTO_ESP;
1521 
1522 	/*
1523 	 * Copy the mbuf to avoid multiple free, as both
1524 	 * esp4_input (which we call) and udp_input (which
1525 	 * called us) free the mbuf.
1526 	 */
1527 	if ((n = m_dup(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
1528 		printf("udp4_espinudp: m_dup failed\n");
1529 		return 0;
1530 	}
1531 
1532 	/*
1533 	 * Add a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember
1534 	 * the source UDP port. This is required if we want
1535 	 * to select the right SPD for multiple hosts behind
1536 	 * same NAT
1537 	 */
1538 	if ((tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS,
1539 	    sizeof(sport) + sizeof(dport), M_DONTWAIT)) == NULL) {
1540 		printf("udp4_espinudp: m_tag_get failed\n");
1541 		m_freem(n);
1542 		return 0;
1543 	}
1544 	((u_int16_t *)(tag + 1))[0] = sport;
1545 	((u_int16_t *)(tag + 1))[1] = dport;
1546 	m_tag_prepend(n, tag);
1547 
1548 	esp4_input(n, iphdrlen);
1549 
1550 	/* We handled it, it shoudln't be handled by UDP */
1551 	return 1;
1552 }
1553 #endif
1554