xref: /netbsd-src/sys/netinet/udp_usrreq.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: udp_usrreq.c,v 1.83 2001/07/25 23:28:02 itojun 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. All advertising materials mentioning features or use of this software
45  *    must display the following acknowledgement:
46  *	This product includes software developed by the University of
47  *	California, Berkeley and its contributors.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
65  */
66 
67 #include "opt_inet.h"
68 #include "opt_ipsec.h"
69 #include "opt_inet_csum.h"
70 #include "opt_ipkdb.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 
84 #include <uvm/uvm_extern.h>
85 #include <sys/sysctl.h>
86 
87 #include <net/if.h>
88 #include <net/route.h>
89 
90 #include <netinet/in.h>
91 #include <netinet/in_systm.h>
92 #include <netinet/in_var.h>
93 #include <netinet/ip.h>
94 #include <netinet/in_pcb.h>
95 #include <netinet/ip_var.h>
96 #include <netinet/ip_icmp.h>
97 #include <netinet/udp.h>
98 #include <netinet/udp_var.h>
99 
100 #ifdef INET6
101 #include <netinet/ip6.h>
102 #include <netinet/icmp6.h>
103 #include <netinet6/ip6_var.h>
104 #include <netinet6/in6_pcb.h>
105 #include <netinet6/udp6_var.h>
106 #endif
107 
108 #ifdef PULLDOWN_TEST
109 #ifndef INET6
110 /* always need ip6.h for IP6_EXTHDR_GET */
111 #include <netinet/ip6.h>
112 #endif
113 #endif
114 
115 #include "faith.h"
116 #if defined(NFAITH) && NFAITH > 0
117 #include <net/if_faith.h>
118 #endif
119 
120 #include <machine/stdarg.h>
121 
122 #ifdef IPSEC
123 #include <netinet6/ipsec.h>
124 #include <netkey/key.h>
125 #endif /*IPSEC*/
126 
127 #ifdef IPKDB
128 #include <ipkdb/ipkdb.h>
129 #endif
130 
131 /*
132  * UDP protocol implementation.
133  * Per RFC 768, August, 1980.
134  */
135 #ifndef	COMPAT_42
136 int	udpcksum = 1;
137 #else
138 int	udpcksum = 0;		/* XXX */
139 #endif
140 
141 #ifdef INET
142 static void udp4_sendup __P((struct mbuf *, int, struct sockaddr *,
143 	struct socket *));
144 static int udp4_realinput __P((struct sockaddr_in *, struct sockaddr_in *,
145 	struct mbuf *, int));
146 #endif
147 #ifdef INET6
148 static void udp6_sendup __P((struct mbuf *, int, struct sockaddr *,
149 	struct socket *));
150 static	int in6_mcmatch __P((struct in6pcb *, struct in6_addr *,
151 	struct ifnet *));
152 static int udp6_realinput __P((int, struct sockaddr_in6 *,
153 	struct sockaddr_in6 *, struct mbuf *, int));
154 #endif
155 #ifdef INET
156 static	void udp_notify __P((struct inpcb *, int));
157 #endif
158 
159 #ifndef UDBHASHSIZE
160 #define	UDBHASHSIZE	128
161 #endif
162 int	udbhashsize = UDBHASHSIZE;
163 
164 #ifdef UDP_CSUM_COUNTERS
165 #include <sys/device.h>
166 
167 struct evcnt udp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
168     NULL, "udp", "hwcsum bad");
169 struct evcnt udp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
170     NULL, "udp", "hwcsum ok");
171 struct evcnt udp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
172     NULL, "udp", "hwcsum data");
173 struct evcnt udp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
174     NULL, "udp", "swcsum");
175 
176 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
177 
178 #else
179 
180 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
181 
182 #endif /* UDP_CSUM_COUNTERS */
183 
184 void
185 udp_init()
186 {
187 
188 #ifdef INET
189 	in_pcbinit(&udbtable, udbhashsize, udbhashsize);
190 #endif
191 
192 #ifdef UDP_CSUM_COUNTERS
193 	evcnt_attach_static(&udp_hwcsum_bad);
194 	evcnt_attach_static(&udp_hwcsum_ok);
195 	evcnt_attach_static(&udp_hwcsum_data);
196 	evcnt_attach_static(&udp_swcsum);
197 #endif /* UDP_CSUM_COUNTERS */
198 }
199 
200 #ifndef UDP6
201 #ifdef INET
202 void
203 #if __STDC__
204 udp_input(struct mbuf *m, ...)
205 #else
206 udp_input(m, va_alist)
207 	struct mbuf *m;
208 	va_dcl
209 #endif
210 {
211 	va_list ap;
212 	struct sockaddr_in src, dst;
213 	struct ip *ip;
214 	struct udphdr *uh;
215 	int iphlen, proto;
216 	int len;
217 	int n;
218 
219 	va_start(ap, m);
220 	iphlen = va_arg(ap, int);
221 	proto = va_arg(ap, int);
222 	va_end(ap);
223 
224 	udpstat.udps_ipackets++;
225 
226 #ifndef PULLDOWN_TEST
227 	/*
228 	 * Strip IP options, if any; should skip this,
229 	 * make available to user, and use on returned packets,
230 	 * but we don't yet have a way to check the checksum
231 	 * with options still present.
232 	 */
233 	if (iphlen > sizeof (struct ip)) {
234 		ip_stripoptions(m, (struct mbuf *)0);
235 		iphlen = sizeof(struct ip);
236 	}
237 #else
238 	/*
239 	 * we may enable the above code if we save and pass IPv4 options
240 	 * to the userland.
241 	 */
242 #endif
243 
244 	/*
245 	 * Get IP and UDP header together in first mbuf.
246 	 */
247 	ip = mtod(m, struct ip *);
248 #ifndef PULLDOWN_TEST
249 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
250 		if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
251 			udpstat.udps_hdrops++;
252 			return;
253 		}
254 		ip = mtod(m, struct ip *);
255 	}
256 	uh = (struct udphdr *)((caddr_t)ip + iphlen);
257 #else
258 	IP6_EXTHDR_GET(uh, struct udphdr *, m, iphlen, sizeof(struct udphdr));
259 	if (uh == NULL) {
260 		udpstat.udps_hdrops++;
261 		return;
262 	}
263 #endif
264 
265 	/* destination port of 0 is illegal, based on RFC768. */
266 	if (uh->uh_dport == 0)
267 		goto bad;
268 
269 	/*
270 	 * Make mbuf data length reflect UDP length.
271 	 * If not enough data to reflect UDP length, drop.
272 	 */
273 	len = ntohs((u_int16_t)uh->uh_ulen);
274 	if (ip->ip_len != iphlen + len) {
275 		if (ip->ip_len < iphlen + len || len < sizeof(struct udphdr)) {
276 			udpstat.udps_badlen++;
277 			goto bad;
278 		}
279 		m_adj(m, iphlen + len - ip->ip_len);
280 	}
281 
282 	/*
283 	 * Checksum extended UDP header and data.
284 	 */
285 	if (uh->uh_sum) {
286 		switch (m->m_pkthdr.csum_flags &
287 			((m->m_pkthdr.rcvif->if_csum_flags & 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 			UDP_CSUM_COUNTER_INCR(&udp_hwcsum_data);
295 			if ((m->m_pkthdr.csum_data ^ 0xffff) != 0)
296 				goto badcsum;
297 			break;
298 
299 		case M_CSUM_UDPv4:
300 			/* Checksum was okay. */
301 			UDP_CSUM_COUNTER_INCR(&udp_hwcsum_ok);
302 			break;
303 
304 		default:
305 			/* Need to compute it ourselves. */
306 			UDP_CSUM_COUNTER_INCR(&udp_swcsum);
307 			if (in4_cksum(m, IPPROTO_UDP, iphlen, len) != 0)
308 				goto badcsum;
309 			break;
310 		}
311 	}
312 
313 	/* construct source and dst sockaddrs. */
314 	bzero(&src, sizeof(src));
315 	src.sin_family = AF_INET;
316 	src.sin_len = sizeof(struct sockaddr_in);
317 	bcopy(&ip->ip_src, &src.sin_addr, sizeof(src.sin_addr));
318 	src.sin_port = uh->uh_sport;
319 	bzero(&dst, sizeof(dst));
320 	dst.sin_family = AF_INET;
321 	dst.sin_len = sizeof(struct sockaddr_in);
322 	bcopy(&ip->ip_dst, &dst.sin_addr, sizeof(dst.sin_addr));
323 	dst.sin_port = uh->uh_dport;
324 
325 	n = udp4_realinput(&src, &dst, m, iphlen);
326 #ifdef INET6
327 	if (IN_MULTICAST(ip->ip_dst.s_addr) || n == 0) {
328 		struct sockaddr_in6 src6, dst6;
329 
330 		bzero(&src6, sizeof(src6));
331 		src6.sin6_family = AF_INET6;
332 		src6.sin6_len = sizeof(struct sockaddr_in6);
333 		src6.sin6_addr.s6_addr[10] = src6.sin6_addr.s6_addr[11] = 0xff;
334 		bcopy(&ip->ip_src, &src6.sin6_addr.s6_addr[12],
335 			sizeof(ip->ip_src));
336 		src6.sin6_port = uh->uh_sport;
337 		bzero(&dst6, sizeof(dst6));
338 		dst6.sin6_family = AF_INET6;
339 		dst6.sin6_len = sizeof(struct sockaddr_in6);
340 		dst6.sin6_addr.s6_addr[10] = dst6.sin6_addr.s6_addr[11] = 0xff;
341 		bcopy(&ip->ip_dst, &dst6.sin6_addr.s6_addr[12],
342 			sizeof(ip->ip_dst));
343 		dst6.sin6_port = uh->uh_dport;
344 
345 		n += udp6_realinput(AF_INET, &src6, &dst6, m, iphlen);
346 	}
347 #endif
348 
349 	if (n == 0) {
350 		if (m->m_flags & (M_BCAST | M_MCAST)) {
351 			udpstat.udps_noportbcast++;
352 			goto bad;
353 		}
354 		udpstat.udps_noport++;
355 #ifdef IPKDB
356 		if (checkipkdb(&ip->ip_src, uh->uh_sport, uh->uh_dport,
357 				m, iphlen + sizeof(struct udphdr),
358 				m->m_pkthdr.len - iphlen - sizeof(struct udphdr))) {
359 			/*
360 			 * It was a debugger connect packet,
361 			 * just drop it now
362 			 */
363 			goto bad;
364 		}
365 #endif
366 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
367 		m = NULL;
368 	}
369 
370 bad:
371 	if (m)
372 		m_freem(m);
373 	return;
374 
375 badcsum:
376 	m_freem(m);
377 	udpstat.udps_badsum++;
378 }
379 #endif
380 
381 #ifdef INET6
382 int
383 udp6_input(mp, offp, proto)
384 	struct mbuf **mp;
385 	int *offp, proto;
386 {
387 	struct mbuf *m = *mp;
388 	int off = *offp;
389 	struct sockaddr_in6 src, dst;
390 	struct ip6_hdr *ip6;
391 	struct udphdr *uh;
392 	u_int32_t plen, ulen;
393 
394 #ifndef PULLDOWN_TEST
395 	IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
396 #endif
397 	ip6 = mtod(m, struct ip6_hdr *);
398 
399 #if defined(NFAITH) && 0 < NFAITH
400 	if (faithprefix(&ip6->ip6_dst)) {
401 		/* send icmp6 host unreach? */
402 		m_freem(m);
403 		return IPPROTO_DONE;
404 	}
405 #endif
406 
407 	udp6stat.udp6s_ipackets++;
408 
409 	/* check for jumbogram is done in ip6_input.  we can trust pkthdr.len */
410 	plen = m->m_pkthdr.len - off;
411 #ifndef PULLDOWN_TEST
412 	uh = (struct udphdr *)((caddr_t)ip6 + off);
413 #else
414 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
415 	if (uh == NULL) {
416 		ip6stat.ip6s_tooshort++;
417 		return IPPROTO_DONE;
418 	}
419 #endif
420 	ulen = ntohs((u_short)uh->uh_ulen);
421 	/*
422 	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
423 	 * iff payload length > 0xffff.
424 	 */
425 	if (ulen == 0 && plen > 0xffff)
426 		ulen = plen;
427 
428 	if (plen != ulen) {
429 		udp6stat.udp6s_badlen++;
430 		goto bad;
431 	}
432 
433 	/* destination port of 0 is illegal, based on RFC768. */
434 	if (uh->uh_dport == 0)
435 		goto bad;
436 
437 	/* Be proactive about malicious use of IPv4 mapped address */
438 	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
439 	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
440 		/* XXX stat */
441 		goto bad;
442 	}
443 
444 	/*
445 	 * Checksum extended UDP header and data.
446 	 */
447 	if (uh->uh_sum == 0)
448 		udp6stat.udp6s_nosum++;
449 	else if (in6_cksum(m, IPPROTO_UDP, off, ulen) != 0) {
450 		udp6stat.udp6s_badsum++;
451 		goto bad;
452 	}
453 
454 	/*
455 	 * Construct source and dst sockaddrs.
456 	 * Note that ifindex (s6_addr16[1]) is already filled.
457 	 */
458 	bzero(&src, sizeof(src));
459 	src.sin6_family = AF_INET6;
460 	src.sin6_len = sizeof(struct sockaddr_in6);
461 	/* KAME hack: recover scopeid */
462 	(void)in6_recoverscope(&src, &ip6->ip6_src, m->m_pkthdr.rcvif);
463 	src.sin6_port = uh->uh_sport;
464 	bzero(&dst, sizeof(dst));
465 	dst.sin6_family = AF_INET6;
466 	dst.sin6_len = sizeof(struct sockaddr_in6);
467 	/* KAME hack: recover scopeid */
468 	(void)in6_recoverscope(&dst, &ip6->ip6_dst, m->m_pkthdr.rcvif);
469 	dst.sin6_port = uh->uh_dport;
470 
471 	if (udp6_realinput(AF_INET6, &src, &dst, m, off) == 0) {
472 		if (m->m_flags & M_MCAST) {
473 			udp6stat.udp6s_noportmcast++;
474 			goto bad;
475 		}
476 		udp6stat.udp6s_noport++;
477 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
478 		m = NULL;
479 	}
480 
481 bad:
482 	if (m)
483 		m_freem(m);
484 	return IPPROTO_DONE;
485 }
486 #endif
487 
488 #ifdef INET
489 static void
490 udp4_sendup(m, off, src, so)
491 	struct mbuf *m;
492 	int off;	/* offset of data portion */
493 	struct sockaddr *src;
494 	struct socket *so;
495 {
496 	struct mbuf *opts = NULL;
497 	struct mbuf *n;
498 	struct inpcb *inp = NULL;
499 #ifdef INET6
500 	struct in6pcb *in6p = NULL;
501 #endif
502 
503 	if (!so)
504 		return;
505 	switch (so->so_proto->pr_domain->dom_family) {
506 	case AF_INET:
507 		inp = sotoinpcb(so);
508 		break;
509 #ifdef INET6
510 	case AF_INET6:
511 		in6p = sotoin6pcb(so);
512 		break;
513 #endif
514 	default:
515 		return;
516 	}
517 
518 #ifdef IPSEC
519 	/* check AH/ESP integrity. */
520 	if (so != NULL && ipsec4_in_reject_so(m, so)) {
521 		ipsecstat.in_polvio++;
522 		return;
523 	}
524 #endif /*IPSEC*/
525 
526 	if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
527 		if (inp && (inp->inp_flags & INP_CONTROLOPTS
528 			 || so->so_options & SO_TIMESTAMP)) {
529 			struct ip *ip = mtod(n, struct ip *);
530 			ip_savecontrol(inp, &opts, ip, n);
531 		}
532 
533 		m_adj(n, off);
534 		if (sbappendaddr(&so->so_rcv, src, n,
535 				opts) == 0) {
536 			m_freem(n);
537 			if (opts)
538 				m_freem(opts);
539 			udpstat.udps_fullsock++;
540 		} else
541 			sorwakeup(so);
542 	}
543 }
544 #endif
545 
546 #ifdef INET6
547 static void
548 udp6_sendup(m, off, src, so)
549 	struct mbuf *m;
550 	int off;	/* offset of data portion */
551 	struct sockaddr *src;
552 	struct socket *so;
553 {
554 	struct mbuf *opts = NULL;
555 	struct mbuf *n;
556 	struct in6pcb *in6p = NULL;
557 
558 	if (!so)
559 		return;
560 	if (so->so_proto->pr_domain->dom_family != AF_INET6)
561 		return;
562 	in6p = sotoin6pcb(so);
563 
564 #ifdef IPSEC
565 	/* check AH/ESP integrity. */
566 	if (so != NULL && ipsec6_in_reject_so(m, so)) {
567 		ipsec6stat.in_polvio++;
568 		return;
569 	}
570 #endif /*IPSEC*/
571 
572 	if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
573 		if (in6p && (in6p->in6p_flags & IN6P_CONTROLOPTS
574 			  || in6p->in6p_socket->so_options & SO_TIMESTAMP)) {
575 			struct ip6_hdr *ip6 = mtod(n, struct ip6_hdr *);
576 			ip6_savecontrol(in6p, &opts, ip6, n);
577 		}
578 
579 		m_adj(n, off);
580 		if (sbappendaddr(&so->so_rcv, src, n, opts) == 0) {
581 			m_freem(n);
582 			if (opts)
583 				m_freem(opts);
584 			udp6stat.udp6s_fullsock++;
585 		} else
586 			sorwakeup(so);
587 	}
588 }
589 #endif
590 
591 #ifdef INET
592 static int
593 udp4_realinput(src, dst, m, off)
594 	struct sockaddr_in *src;
595 	struct sockaddr_in *dst;
596 	struct mbuf *m;
597 	int off;	/* offset of udphdr */
598 {
599 	u_int16_t *sport, *dport;
600 	int rcvcnt;
601 	struct in_addr *src4, *dst4;
602 	struct inpcb *inp;
603 
604 	rcvcnt = 0;
605 	off += sizeof(struct udphdr);	/* now, offset of payload */
606 
607 	if (src->sin_family != AF_INET || dst->sin_family != AF_INET)
608 		goto bad;
609 
610 	src4 = &src->sin_addr;
611 	sport = &src->sin_port;
612 	dst4 = &dst->sin_addr;
613 	dport = &dst->sin_port;
614 
615 	if (IN_MULTICAST(dst4->s_addr) ||
616 	    in_broadcast(*dst4, m->m_pkthdr.rcvif)) {
617 		struct inpcb *last;
618 		/*
619 		 * Deliver a multicast or broadcast datagram to *all* sockets
620 		 * for which the local and remote addresses and ports match
621 		 * those of the incoming datagram.  This allows more than
622 		 * one process to receive multi/broadcasts on the same port.
623 		 * (This really ought to be done for unicast datagrams as
624 		 * well, but that would cause problems with existing
625 		 * applications that open both address-specific sockets and
626 		 * a wildcard socket listening to the same port -- they would
627 		 * end up receiving duplicates of every unicast datagram.
628 		 * Those applications open the multiple sockets to overcome an
629 		 * inadequacy of the UDP socket interface, but for backwards
630 		 * compatibility we avoid the problem here rather than
631 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
632 		 */
633 
634 		/*
635 		 * KAME note: usually we drop udpiphdr from mbuf here.
636 		 * we need udpiphdr for IPsec processing so we do that later.
637 		 */
638 		/*
639 		 * Locate pcb(s) for datagram.
640 		 */
641 		for (inp = udbtable.inpt_queue.cqh_first;
642 		    inp != (struct inpcb *)&udbtable.inpt_queue;
643 		    inp = inp->inp_queue.cqe_next) {
644 			if (inp->inp_lport != *dport)
645 				continue;
646 			if (!in_nullhost(inp->inp_laddr)) {
647 				if (!in_hosteq(inp->inp_laddr, *dst4))
648 					continue;
649 			}
650 			if (!in_nullhost(inp->inp_faddr)) {
651 				if (!in_hosteq(inp->inp_faddr, *src4) ||
652 				    inp->inp_fport != *sport)
653 					continue;
654 			}
655 
656 			last = inp;
657 			udp4_sendup(m, off, (struct sockaddr *)src,
658 				inp->inp_socket);
659 			rcvcnt++;
660 
661 			/*
662 			 * Don't look for additional matches if this one does
663 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
664 			 * socket options set.  This heuristic avoids searching
665 			 * through all pcbs in the common case of a non-shared
666 			 * port.  It assumes that an application will never
667 			 * clear these options after setting them.
668 			 */
669 			if ((inp->inp_socket->so_options &
670 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
671 				break;
672 		}
673 	} else {
674 		/*
675 		 * Locate pcb for datagram.
676 		 */
677 		inp = in_pcblookup_connect(&udbtable, *src4, *sport, *dst4, *dport);
678 		if (inp == 0) {
679 			++udpstat.udps_pcbhashmiss;
680 			inp = in_pcblookup_bind(&udbtable, *dst4, *dport);
681 			if (inp == 0)
682 				return rcvcnt;
683 		}
684 
685 		udp4_sendup(m, off, (struct sockaddr *)src, inp->inp_socket);
686 		rcvcnt++;
687 	}
688 
689 bad:
690 	return rcvcnt;
691 }
692 #endif
693 
694 #ifdef INET6
695 static int
696 in6_mcmatch(in6p, ia6, ifp)
697 	struct in6pcb *in6p;
698 	struct in6_addr *ia6;
699 	struct ifnet *ifp;
700 {
701 	struct ip6_moptions *im6o = in6p->in6p_moptions;
702 	struct in6_multi_mship *imm;
703 
704 	if (im6o == NULL)
705 		return 0;
706 
707 	for (imm = im6o->im6o_memberships.lh_first; imm != NULL;
708 	     imm = imm->i6mm_chain.le_next) {
709 		if ((ifp == NULL ||
710 		     imm->i6mm_maddr->in6m_ifp == ifp) &&
711 		    IN6_ARE_ADDR_EQUAL(&imm->i6mm_maddr->in6m_addr,
712 				       ia6))
713 			return 1;
714 	}
715 	return 0;
716 }
717 
718 static int
719 udp6_realinput(af, src, dst, m, off)
720 	int af;		/* af on packet */
721 	struct sockaddr_in6 *src;
722 	struct sockaddr_in6 *dst;
723 	struct mbuf *m;
724 	int off;	/* offset of udphdr */
725 {
726 	u_int16_t sport, dport;
727 	int rcvcnt;
728 	struct in6_addr src6, dst6;
729 	const struct in_addr *dst4;
730 	struct in6pcb *in6p;
731 
732 	rcvcnt = 0;
733 	off += sizeof(struct udphdr);	/* now, offset of payload */
734 
735 	if (af != AF_INET && af != AF_INET6)
736 		goto bad;
737 	if (src->sin6_family != AF_INET6 || dst->sin6_family != AF_INET6)
738 		goto bad;
739 
740 	in6_embedscope(&src6, src, NULL, NULL);
741 	sport = src->sin6_port;
742 	in6_embedscope(&dst6, dst, NULL, NULL);
743 	dport = dst->sin6_port;
744 	dst4 = (struct in_addr *)&dst->sin6_addr.s6_addr32[12];
745 
746 	if (IN6_IS_ADDR_MULTICAST(&dst6) ||
747 	    (af == AF_INET && IN_MULTICAST(dst4->s_addr))) {
748 		struct in6pcb *last;
749 		/*
750 		 * Deliver a multicast or broadcast datagram to *all* sockets
751 		 * for which the local and remote addresses and ports match
752 		 * those of the incoming datagram.  This allows more than
753 		 * one process to receive multi/broadcasts on the same port.
754 		 * (This really ought to be done for unicast datagrams as
755 		 * well, but that would cause problems with existing
756 		 * applications that open both address-specific sockets and
757 		 * a wildcard socket listening to the same port -- they would
758 		 * end up receiving duplicates of every unicast datagram.
759 		 * Those applications open the multiple sockets to overcome an
760 		 * inadequacy of the UDP socket interface, but for backwards
761 		 * compatibility we avoid the problem here rather than
762 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
763 		 */
764 
765 		/*
766 		 * KAME note: usually we drop udpiphdr from mbuf here.
767 		 * we need udpiphdr for IPsec processing so we do that later.
768 		 */
769 		/*
770 		 * Locate pcb(s) for datagram.
771 		 */
772 		for (in6p = udb6.in6p_next; in6p != &udb6;
773 		     in6p = in6p->in6p_next) {
774 			if (in6p->in6p_lport != dport)
775 				continue;
776 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
777 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &dst6) &&
778 				    !in6_mcmatch(in6p, &dst6, m->m_pkthdr.rcvif))
779 					continue;
780 			}
781 #ifndef INET6_BINDV6ONLY
782 			else {
783 				if (IN6_IS_ADDR_V4MAPPED(&dst6) &&
784 				    (in6p->in6p_flags & IN6P_BINDV6ONLY))
785 					continue;
786 			}
787 #endif
788 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
789 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
790 				    &src6) || in6p->in6p_fport != sport)
791 					continue;
792 			}
793 #ifndef INET6_BINDV6ONLY
794 			else {
795 				if (IN6_IS_ADDR_V4MAPPED(&src6) &&
796 				    (in6p->in6p_flags & IN6P_BINDV6ONLY))
797 					continue;
798 			}
799 #endif
800 
801 			last = in6p;
802 			udp6_sendup(m, off, (struct sockaddr *)src,
803 				in6p->in6p_socket);
804 			rcvcnt++;
805 
806 			/*
807 			 * Don't look for additional matches if this one does
808 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
809 			 * socket options set.  This heuristic avoids searching
810 			 * through all pcbs in the common case of a non-shared
811 			 * port.  It assumes that an application will never
812 			 * clear these options after setting them.
813 			 */
814 			if ((in6p->in6p_socket->so_options &
815 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
816 				break;
817 		}
818 	} else {
819 		/*
820 		 * Locate pcb for datagram.
821 		 */
822 		in6p = in6_pcblookup_connect(&udb6, &src6, sport,
823 		    &dst6, dport, 0);
824 		if (in6p == 0) {
825 			++udpstat.udps_pcbhashmiss;
826 			in6p = in6_pcblookup_bind(&udb6, &dst6, dport, 0);
827 			if (in6p == 0)
828 				return rcvcnt;
829 		}
830 
831 		udp6_sendup(m, off, (struct sockaddr *)src, in6p->in6p_socket);
832 		rcvcnt++;
833 	}
834 
835 bad:
836 	return rcvcnt;
837 }
838 #endif
839 
840 #else /*UDP6*/
841 
842 void
843 #if __STDC__
844 udp_input(struct mbuf *m, ...)
845 #else
846 udp_input(m, va_alist)
847 	struct mbuf *m;
848 	va_dcl
849 #endif
850 {
851 	int proto;
852 	struct ip *ip;
853 	struct udphdr *uh;
854 	struct inpcb *inp;
855 	struct mbuf *opts = 0;
856 	int len;
857 	struct ip save_ip;
858 	int iphlen;
859 	va_list ap;
860 	struct sockaddr_in udpsrc;
861 	struct sockaddr *sa;
862 
863 	va_start(ap, m);
864 	iphlen = va_arg(ap, int);
865 	proto = va_arg(ap, int);
866 	va_end(ap);
867 
868 	udpstat.udps_ipackets++;
869 
870 	/*
871 	 * Strip IP options, if any; should skip this,
872 	 * make available to user, and use on returned packets,
873 	 * but we don't yet have a way to check the checksum
874 	 * with options still present.
875 	 */
876 	if (iphlen > sizeof (struct ip)) {
877 		ip_stripoptions(m, (struct mbuf *)0);
878 		iphlen = sizeof(struct ip);
879 	}
880 
881 	/*
882 	 * Get IP and UDP header together in first mbuf.
883 	 */
884 	ip = mtod(m, struct ip *);
885 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
886 		if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
887 			udpstat.udps_hdrops++;
888 			return;
889 		}
890 		ip = mtod(m, struct ip *);
891 	}
892 	uh = (struct udphdr *)((caddr_t)ip + iphlen);
893 
894 	/* destination port of 0 is illegal, based on RFC768. */
895 	if (uh->uh_dport == 0)
896 		goto bad;
897 
898 	/*
899 	 * Make mbuf data length reflect UDP length.
900 	 * If not enough data to reflect UDP length, drop.
901 	 */
902 	len = ntohs((u_int16_t)uh->uh_ulen);
903 	if (ip->ip_len != iphlen + len) {
904 		if (ip->ip_len < iphlen + len || len < sizeof(struct udphdr)) {
905 			udpstat.udps_badlen++;
906 			goto bad;
907 		}
908 		m_adj(m, iphlen + len - ip->ip_len);
909 	}
910 	/*
911 	 * Save a copy of the IP header in case we want restore it
912 	 * for sending an ICMP error message in response.
913 	 */
914 	save_ip = *ip;
915 
916 	/*
917 	 * Checksum extended UDP header and data.
918 	 */
919 	if (uh->uh_sum) {
920 		switch (m->m_pkthdr.csum_flags &
921 			((m->m_pkthdr.rcvif->if_csum_flags & M_CSUM_UDPv4) |
922 			 M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
923 		case M_CSUM_UDPv4|M_CSUM_TCP_UDP_BAD:
924 			UDP_CSUM_COUNTER_INCR(&udp_hwcsum_bad);
925 			goto badcsum;
926 
927 		case M_CSUM_UDPv4|M_CSUM_DATA:
928 			UDP_CSUM_COUNTER_INCR(&udp_hwcsum_data);
929 			if ((m->m_pkthdr.csum_data ^ 0xffff) != 0)
930 				goto badcsum;
931 			break;
932 
933 		case M_CSUM_UDPv4:
934 			/* Checksum was okay. */
935 			UDP_CSUM_COUNTER_INCR(&udp_hwcsum_ok);
936 			break;
937 
938 		default:
939 			/* Need to compute it ourselves. */
940 			UDP_CSUM_COUNTER_INCR(&udp_swcsum);
941 			bzero(((struct ipovly *)ip)->ih_x1,
942 			    sizeof ((struct ipovly *)ip)->ih_x1);
943 			((struct ipovly *)ip)->ih_len = uh->uh_ulen;
944 			if (in_cksum(m, len + sizeof (struct ip)) != 0)
945 				goto badcsum;
946 			break;
947 		}
948 	}
949 
950 	/*
951 	 * Construct sockaddr format source address.
952 	 */
953 	udpsrc.sin_family = AF_INET;
954 	udpsrc.sin_len = sizeof(struct sockaddr_in);
955 	udpsrc.sin_addr = ip->ip_src;
956 	udpsrc.sin_port = uh->uh_sport;
957 	bzero((caddr_t)udpsrc.sin_zero, sizeof(udpsrc.sin_zero));
958 
959 	if (IN_MULTICAST(ip->ip_dst.s_addr) ||
960 	    in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) {
961 		struct inpcb *last;
962 		/*
963 		 * Deliver a multicast or broadcast datagram to *all* sockets
964 		 * for which the local and remote addresses and ports match
965 		 * those of the incoming datagram.  This allows more than
966 		 * one process to receive multi/broadcasts on the same port.
967 		 * (This really ought to be done for unicast datagrams as
968 		 * well, but that would cause problems with existing
969 		 * applications that open both address-specific sockets and
970 		 * a wildcard socket listening to the same port -- they would
971 		 * end up receiving duplicates of every unicast datagram.
972 		 * Those applications open the multiple sockets to overcome an
973 		 * inadequacy of the UDP socket interface, but for backwards
974 		 * compatibility we avoid the problem here rather than
975 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
976 		 */
977 
978 		iphlen += sizeof(struct udphdr);
979 		/*
980 		 * KAME note: usually we drop udpiphdr from mbuf here.
981 		 * we need udpiphdr for IPsec processing so we do that later.
982 		 */
983 		/*
984 		 * Locate pcb(s) for datagram.
985 		 * (Algorithm copied from raw_intr().)
986 		 */
987 		last = NULL;
988 		for (inp = udbtable.inpt_queue.cqh_first;
989 		    inp != (struct inpcb *)&udbtable.inpt_queue;
990 		    inp = inp->inp_queue.cqe_next) {
991 			if (inp->inp_lport != uh->uh_dport)
992 				continue;
993 			if (!in_nullhost(inp->inp_laddr)) {
994 				if (!in_hosteq(inp->inp_laddr, ip->ip_dst))
995 					continue;
996 			}
997 			if (!in_nullhost(inp->inp_faddr)) {
998 				if (!in_hosteq(inp->inp_faddr, ip->ip_src) ||
999 				    inp->inp_fport != uh->uh_sport)
1000 					continue;
1001 			}
1002 
1003 			if (last != NULL) {
1004 				struct mbuf *n;
1005 
1006 #ifdef IPSEC
1007 				/* check AH/ESP integrity. */
1008 				if (last != NULL && ipsec4_in_reject(m, last)) {
1009 					ipsecstat.in_polvio++;
1010 					/* do not inject data to pcb */
1011 				} else
1012 #endif /*IPSEC*/
1013 				if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
1014 					if (last->inp_flags & INP_CONTROLOPTS
1015 					    || last->inp_socket->so_options &
1016 					       SO_TIMESTAMP) {
1017 						ip_savecontrol(last, &opts,
1018 						    ip, n);
1019 					}
1020 					m_adj(n, iphlen);
1021 					sa = (struct sockaddr *)&udpsrc;
1022 					if (sbappendaddr(
1023 					    &last->inp_socket->so_rcv,
1024 					    sa, n, opts) == 0) {
1025 						m_freem(n);
1026 						if (opts)
1027 							m_freem(opts);
1028 						udpstat.udps_fullsock++;
1029 					} else
1030 						sorwakeup(last->inp_socket);
1031 					opts = 0;
1032 				}
1033 			}
1034 			last = inp;
1035 			/*
1036 			 * Don't look for additional matches if this one does
1037 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
1038 			 * socket options set.  This heuristic avoids searching
1039 			 * through all pcbs in the common case of a non-shared
1040 			 * port.  It * assumes that an application will never
1041 			 * clear these options after setting them.
1042 			 */
1043 			if ((last->inp_socket->so_options &
1044 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
1045 				break;
1046 		}
1047 
1048 		if (last == NULL) {
1049 			/*
1050 			 * No matching pcb found; discard datagram.
1051 			 * (No need to send an ICMP Port Unreachable
1052 			 * for a broadcast or multicast datgram.)
1053 			 */
1054 			udpstat.udps_noportbcast++;
1055 			goto bad;
1056 		}
1057 #ifdef IPSEC
1058 		/* check AH/ESP integrity. */
1059 		if (last != NULL && ipsec4_in_reject(m, last)) {
1060 			ipsecstat.in_polvio++;
1061 			goto bad;
1062 		}
1063 #endif /*IPSEC*/
1064 		if (last->inp_flags & INP_CONTROLOPTS ||
1065 		    last->inp_socket->so_options & SO_TIMESTAMP)
1066 			ip_savecontrol(last, &opts, ip, m);
1067 		m->m_len -= iphlen;
1068 		m->m_pkthdr.len -= iphlen;
1069 		m->m_data += iphlen;
1070 		sa = (struct sockaddr *)&udpsrc;
1071 		if (sbappendaddr(&last->inp_socket->so_rcv, sa, m, opts) == 0) {
1072 			udpstat.udps_fullsock++;
1073 			goto bad;
1074 		}
1075 		sorwakeup(last->inp_socket);
1076 		return;
1077 	}
1078 	/*
1079 	 * Locate pcb for datagram.
1080 	 */
1081 	inp = in_pcblookup_connect(&udbtable, ip->ip_src, uh->uh_sport,
1082 	    ip->ip_dst, uh->uh_dport);
1083 	if (inp == 0) {
1084 		++udpstat.udps_pcbhashmiss;
1085 		inp = in_pcblookup_bind(&udbtable, ip->ip_dst, uh->uh_dport);
1086 		if (inp == 0) {
1087 			if (m->m_flags & (M_BCAST | M_MCAST)) {
1088 				udpstat.udps_noportbcast++;
1089 				goto bad;
1090 			}
1091 			udpstat.udps_noport++;
1092 			*ip = save_ip;
1093 #ifdef IPKDB
1094 			if (checkipkdb(&ip->ip_src,
1095 				       uh->uh_sport,
1096 				       uh->uh_dport,
1097 				       m,
1098 				       iphlen + sizeof(struct udphdr),
1099 				       len - sizeof(struct udphdr)))
1100 			/* It was a debugger connect packet, just drop it now */
1101 				goto bad;
1102 #endif
1103 			icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
1104 			return;
1105 		}
1106 	}
1107 #ifdef IPSEC
1108 	if (inp != NULL && ipsec4_in_reject(m, inp)) {
1109 		ipsecstat.in_polvio++;
1110 		goto bad;
1111 	}
1112 #endif /*IPSEC*/
1113 
1114 	/*
1115 	 * Stuff source address and datagram in user buffer.
1116 	 */
1117 	if (inp->inp_flags & INP_CONTROLOPTS ||
1118 	    inp->inp_socket->so_options & SO_TIMESTAMP)
1119 		ip_savecontrol(inp, &opts, ip, m);
1120 	iphlen += sizeof(struct udphdr);
1121 	m->m_len -= iphlen;
1122 	m->m_pkthdr.len -= iphlen;
1123 	m->m_data += iphlen;
1124 	sa = (struct sockaddr *)&udpsrc;
1125 	if (sbappendaddr(&inp->inp_socket->so_rcv, sa, m, opts) == 0) {
1126 		udpstat.udps_fullsock++;
1127 		goto bad;
1128 	}
1129 	sorwakeup(inp->inp_socket);
1130 	return;
1131 bad:
1132 	m_freem(m);
1133 	if (opts)
1134 		m_freem(opts);
1135 	return;
1136 
1137 badcsum:
1138 	udpstat.udps_badsum++;
1139 	m_freem(m);
1140 }
1141 #endif /*UDP6*/
1142 
1143 #ifdef INET
1144 /*
1145  * Notify a udp user of an asynchronous error;
1146  * just wake up so that he can collect error status.
1147  */
1148 static void
1149 udp_notify(inp, errno)
1150 	struct inpcb *inp;
1151 	int errno;
1152 {
1153 
1154 	inp->inp_socket->so_error = errno;
1155 	sorwakeup(inp->inp_socket);
1156 	sowwakeup(inp->inp_socket);
1157 }
1158 
1159 void *
1160 udp_ctlinput(cmd, sa, v)
1161 	int cmd;
1162 	struct sockaddr *sa;
1163 	void *v;
1164 {
1165 	struct ip *ip = v;
1166 	struct udphdr *uh;
1167 	void (*notify) __P((struct inpcb *, int)) = udp_notify;
1168 	int errno;
1169 
1170 	if (sa->sa_family != AF_INET
1171 	 || sa->sa_len != sizeof(struct sockaddr_in))
1172 		return NULL;
1173 	if ((unsigned)cmd >= PRC_NCMDS)
1174 		return NULL;
1175 	errno = inetctlerrmap[cmd];
1176 	if (PRC_IS_REDIRECT(cmd))
1177 		notify = in_rtchange, ip = 0;
1178 	else if (cmd == PRC_HOSTDEAD)
1179 		ip = 0;
1180 	else if (errno == 0)
1181 		return NULL;
1182 	if (ip) {
1183 		uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
1184 		in_pcbnotify(&udbtable, satosin(sa)->sin_addr, uh->uh_dport,
1185 		    ip->ip_src, uh->uh_sport, errno, notify);
1186 
1187 		/* XXX mapped address case */
1188 	} else
1189 		in_pcbnotifyall(&udbtable, satosin(sa)->sin_addr, errno,
1190 		    notify);
1191 	return NULL;
1192 }
1193 
1194 int
1195 #if __STDC__
1196 udp_output(struct mbuf *m, ...)
1197 #else
1198 udp_output(m, va_alist)
1199 	struct mbuf *m;
1200 	va_dcl
1201 #endif
1202 {
1203 	struct inpcb *inp;
1204 	struct udpiphdr *ui;
1205 	int len = m->m_pkthdr.len;
1206 	int error = 0;
1207 	va_list ap;
1208 
1209 	va_start(ap, m);
1210 	inp = va_arg(ap, struct inpcb *);
1211 	va_end(ap);
1212 
1213 	/*
1214 	 * Calculate data length and get a mbuf
1215 	 * for UDP and IP headers.
1216 	 */
1217 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
1218 	if (m == 0) {
1219 		error = ENOBUFS;
1220 		goto release;
1221 	}
1222 
1223 	/*
1224 	 * Compute the packet length of the IP header, and
1225 	 * punt if the length looks bogus.
1226 	 */
1227 	if ((len + sizeof(struct udpiphdr)) > IP_MAXPACKET) {
1228 		error = EMSGSIZE;
1229 		goto release;
1230 	}
1231 
1232 	/*
1233 	 * Fill in mbuf with extended UDP header
1234 	 * and addresses and length put into network format.
1235 	 */
1236 	ui = mtod(m, struct udpiphdr *);
1237 	ui->ui_pr = IPPROTO_UDP;
1238 	ui->ui_src = inp->inp_laddr;
1239 	ui->ui_dst = inp->inp_faddr;
1240 	ui->ui_sport = inp->inp_lport;
1241 	ui->ui_dport = inp->inp_fport;
1242 	ui->ui_ulen = htons((u_int16_t)len + sizeof(struct udphdr));
1243 
1244 	/*
1245 	 * Set up checksum and output datagram.
1246 	 */
1247 	if (udpcksum) {
1248 		/*
1249 		 * XXX Cache pseudo-header checksum part for
1250 		 * XXX "connected" UDP sockets.
1251 		 */
1252 		ui->ui_sum = in_cksum_phdr(ui->ui_src.s_addr,
1253 		    ui->ui_dst.s_addr, htons((u_int16_t)len +
1254 		    sizeof(struct udphdr) + IPPROTO_UDP));
1255 		m->m_pkthdr.csum_flags = M_CSUM_UDPv4;
1256 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1257 	} else
1258 		ui->ui_sum = 0;
1259 	((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
1260 	((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl;	/* XXX */
1261 	((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos;	/* XXX */
1262 	udpstat.udps_opackets++;
1263 
1264 #ifdef IPSEC
1265 	if (ipsec_setsocket(m, inp->inp_socket) != 0) {
1266 		error = ENOBUFS;
1267 		goto release;
1268 	}
1269 #endif /*IPSEC*/
1270 
1271 	return (ip_output(m, inp->inp_options, &inp->inp_route,
1272 	    inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST),
1273 	    inp->inp_moptions));
1274 
1275 release:
1276 	m_freem(m);
1277 	return (error);
1278 }
1279 
1280 int	udp_sendspace = 9216;		/* really max datagram size */
1281 int	udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
1282 					/* 40 1K datagrams */
1283 
1284 /*ARGSUSED*/
1285 int
1286 udp_usrreq(so, req, m, nam, control, p)
1287 	struct socket *so;
1288 	int req;
1289 	struct mbuf *m, *nam, *control;
1290 	struct proc *p;
1291 {
1292 	struct inpcb *inp;
1293 	int s;
1294 	int error = 0;
1295 
1296 	if (req == PRU_CONTROL)
1297 		return (in_control(so, (long)m, (caddr_t)nam,
1298 		    (struct ifnet *)control, p));
1299 
1300 	if (req == PRU_PURGEIF) {
1301 		in_pcbpurgeif0(&udbtable, (struct ifnet *)control);
1302 		in_purgeif((struct ifnet *)control);
1303 		in_pcbpurgeif(&udbtable, (struct ifnet *)control);
1304 		return (0);
1305 	}
1306 
1307 	s = splsoftnet();
1308 	inp = sotoinpcb(so);
1309 #ifdef DIAGNOSTIC
1310 	if (req != PRU_SEND && req != PRU_SENDOOB && control)
1311 		panic("udp_usrreq: unexpected control mbuf");
1312 #endif
1313 	if (inp == 0 && req != PRU_ATTACH) {
1314 		error = EINVAL;
1315 		goto release;
1316 	}
1317 
1318 	/*
1319 	 * Note: need to block udp_input while changing
1320 	 * the udp pcb queue and/or pcb addresses.
1321 	 */
1322 	switch (req) {
1323 
1324 	case PRU_ATTACH:
1325 		if (inp != 0) {
1326 			error = EISCONN;
1327 			break;
1328 		}
1329 		if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1330 			error = soreserve(so, udp_sendspace, udp_recvspace);
1331 			if (error)
1332 				break;
1333 		}
1334 		error = in_pcballoc(so, &udbtable);
1335 		if (error)
1336 			break;
1337 		inp = sotoinpcb(so);
1338 		inp->inp_ip.ip_ttl = ip_defttl;
1339 		break;
1340 
1341 	case PRU_DETACH:
1342 		in_pcbdetach(inp);
1343 		break;
1344 
1345 	case PRU_BIND:
1346 		error = in_pcbbind(inp, nam, p);
1347 		break;
1348 
1349 	case PRU_LISTEN:
1350 		error = EOPNOTSUPP;
1351 		break;
1352 
1353 	case PRU_CONNECT:
1354 		error = in_pcbconnect(inp, nam);
1355 		if (error)
1356 			break;
1357 		soisconnected(so);
1358 		break;
1359 
1360 	case PRU_CONNECT2:
1361 		error = EOPNOTSUPP;
1362 		break;
1363 
1364 	case PRU_DISCONNECT:
1365 		/*soisdisconnected(so);*/
1366 		so->so_state &= ~SS_ISCONNECTED;	/* XXX */
1367 		in_pcbdisconnect(inp);
1368 		inp->inp_laddr = zeroin_addr;		/* XXX */
1369 		in_pcbstate(inp, INP_BOUND);		/* XXX */
1370 		break;
1371 
1372 	case PRU_SHUTDOWN:
1373 		socantsendmore(so);
1374 		break;
1375 
1376 	case PRU_RCVD:
1377 		error = EOPNOTSUPP;
1378 		break;
1379 
1380 	case PRU_SEND:
1381 		if (control && control->m_len) {
1382 			m_freem(control);
1383 			m_freem(m);
1384 			error = EINVAL;
1385 			break;
1386 		}
1387 	{
1388 		struct in_addr laddr;			/* XXX */
1389 
1390 		if (nam) {
1391 			laddr = inp->inp_laddr;		/* XXX */
1392 			if ((so->so_state & SS_ISCONNECTED) != 0) {
1393 				error = EISCONN;
1394 				goto die;
1395 			}
1396 			error = in_pcbconnect(inp, nam);
1397 			if (error) {
1398 			die:
1399 				m_freem(m);
1400 				break;
1401 			}
1402 		} else {
1403 			if ((so->so_state & SS_ISCONNECTED) == 0) {
1404 				error = ENOTCONN;
1405 				goto die;
1406 			}
1407 		}
1408 		error = udp_output(m, inp);
1409 		if (nam) {
1410 			in_pcbdisconnect(inp);
1411 			inp->inp_laddr = laddr;		/* XXX */
1412 			in_pcbstate(inp, INP_BOUND);	/* XXX */
1413 		}
1414 	}
1415 		break;
1416 
1417 	case PRU_SENSE:
1418 		/*
1419 		 * stat: don't bother with a blocksize.
1420 		 */
1421 		splx(s);
1422 		return (0);
1423 
1424 	case PRU_RCVOOB:
1425 		error =  EOPNOTSUPP;
1426 		break;
1427 
1428 	case PRU_SENDOOB:
1429 		m_freem(control);
1430 		m_freem(m);
1431 		error =  EOPNOTSUPP;
1432 		break;
1433 
1434 	case PRU_SOCKADDR:
1435 		in_setsockaddr(inp, nam);
1436 		break;
1437 
1438 	case PRU_PEERADDR:
1439 		in_setpeeraddr(inp, nam);
1440 		break;
1441 
1442 	default:
1443 		panic("udp_usrreq");
1444 	}
1445 
1446 release:
1447 	splx(s);
1448 	return (error);
1449 }
1450 
1451 /*
1452  * Sysctl for udp variables.
1453  */
1454 int
1455 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
1456 	int *name;
1457 	u_int namelen;
1458 	void *oldp;
1459 	size_t *oldlenp;
1460 	void *newp;
1461 	size_t newlen;
1462 {
1463 	/* All sysctl names at this level are terminal. */
1464 	if (namelen != 1)
1465 		return (ENOTDIR);
1466 
1467 	switch (name[0]) {
1468 	case UDPCTL_CHECKSUM:
1469 		return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum));
1470 	case UDPCTL_SENDSPACE:
1471 		return (sysctl_int(oldp, oldlenp, newp, newlen,
1472 		    &udp_sendspace));
1473 	case UDPCTL_RECVSPACE:
1474 		return (sysctl_int(oldp, oldlenp, newp, newlen,
1475 		    &udp_recvspace));
1476 	default:
1477 		return (ENOPROTOOPT);
1478 	}
1479 	/* NOTREACHED */
1480 }
1481 #endif
1482