xref: /freebsd/sys/netinet/udp_usrreq.c (revision 83d9fd40d5cb67ff1e805523a6fae48c3389f396)
1 /*-
2  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
3  *	The Regents of the University of California.
4  * Copyright (c) 2008 Robert N. M. Watson
5  * Copyright (c) 2010-2011 Juniper Networks, Inc.
6  * Copyright (c) 2014 Kevin Lo
7  * All rights reserved.
8  *
9  * Portions of this software were developed by Robert N. M. Watson under
10  * contract to Juniper Networks, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "opt_inet.h"
43 #include "opt_inet6.h"
44 #include "opt_ipsec.h"
45 #include "opt_rss.h"
46 
47 #include <sys/param.h>
48 #include <sys/domain.h>
49 #include <sys/eventhandler.h>
50 #include <sys/jail.h>
51 #include <sys/kernel.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/priv.h>
56 #include <sys/proc.h>
57 #include <sys/protosw.h>
58 #include <sys/sdt.h>
59 #include <sys/signalvar.h>
60 #include <sys/socket.h>
61 #include <sys/socketvar.h>
62 #include <sys/sx.h>
63 #include <sys/sysctl.h>
64 #include <sys/syslog.h>
65 #include <sys/systm.h>
66 
67 #include <vm/uma.h>
68 
69 #include <net/if.h>
70 #include <net/if_var.h>
71 #include <net/route.h>
72 #include <net/rss_config.h>
73 
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_pcb.h>
77 #include <netinet/in_systm.h>
78 #include <netinet/in_var.h>
79 #include <netinet/ip.h>
80 #ifdef INET6
81 #include <netinet/ip6.h>
82 #endif
83 #include <netinet/ip_icmp.h>
84 #include <netinet/icmp_var.h>
85 #include <netinet/ip_var.h>
86 #include <netinet/ip_options.h>
87 #ifdef INET6
88 #include <netinet6/ip6_var.h>
89 #endif
90 #include <netinet/udp.h>
91 #include <netinet/udp_var.h>
92 #include <netinet/udplite.h>
93 #include <netinet/in_rss.h>
94 
95 #include <netipsec/ipsec_support.h>
96 
97 #include <machine/in_cksum.h>
98 
99 #include <security/mac/mac_framework.h>
100 
101 /*
102  * UDP and UDP-Lite protocols implementation.
103  * Per RFC 768, August, 1980.
104  * Per RFC 3828, July, 2004.
105  */
106 
107 /*
108  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
109  * removes the only data integrity mechanism for packets and malformed
110  * packets that would otherwise be discarded due to bad checksums, and may
111  * cause problems (especially for NFS data blocks).
112  */
113 VNET_DEFINE(int, udp_cksum) = 1;
114 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
115     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
116 
117 int	udp_log_in_vain = 0;
118 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
119     &udp_log_in_vain, 0, "Log all incoming UDP packets");
120 
121 VNET_DEFINE(int, udp_blackhole) = 0;
122 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
123     &VNET_NAME(udp_blackhole), 0,
124     "Do not send port unreachables for refused connects");
125 
126 static VNET_DEFINE(int, udp_require_l2_bcast) = 0;
127 #define	V_udp_require_l2_bcast		VNET(udp_require_l2_bcast)
128 SYSCTL_INT(_net_inet_udp, OID_AUTO, require_l2_bcast, CTLFLAG_VNET | CTLFLAG_RW,
129     &VNET_NAME(udp_require_l2_bcast), 0,
130     "Only treat packets sent to an L2 broadcast address as broadcast packets");
131 
132 u_long	udp_sendspace = 9216;		/* really max datagram size */
133 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
134     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
135 
136 u_long	udp_recvspace = 40 * (1024 +
137 #ifdef INET6
138 				      sizeof(struct sockaddr_in6)
139 #else
140 				      sizeof(struct sockaddr_in)
141 #endif
142 				      );	/* 40 1K datagrams */
143 
144 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
145     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
146 
147 VNET_DEFINE(struct inpcbhead, udb);		/* from udp_var.h */
148 VNET_DEFINE(struct inpcbinfo, udbinfo);
149 VNET_DEFINE(struct inpcbhead, ulitecb);
150 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
151 static VNET_DEFINE(uma_zone_t, udpcb_zone);
152 #define	V_udpcb_zone			VNET(udpcb_zone)
153 
154 #ifndef UDBHASHSIZE
155 #define	UDBHASHSIZE	128
156 #endif
157 
158 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);		/* from udp_var.h */
159 VNET_PCPUSTAT_SYSINIT(udpstat);
160 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
161     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
162 
163 #ifdef VIMAGE
164 VNET_PCPUSTAT_SYSUNINIT(udpstat);
165 #endif /* VIMAGE */
166 #ifdef INET
167 static void	udp_detach(struct socket *so);
168 static int	udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
169 		    struct mbuf *, struct thread *);
170 #endif
171 
172 static void
173 udp_zone_change(void *tag)
174 {
175 
176 	uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
177 	uma_zone_set_max(V_udpcb_zone, maxsockets);
178 }
179 
180 static int
181 udp_inpcb_init(void *mem, int size, int flags)
182 {
183 	struct inpcb *inp;
184 
185 	inp = mem;
186 	INP_LOCK_INIT(inp, "inp", "udpinp");
187 	return (0);
188 }
189 
190 static int
191 udplite_inpcb_init(void *mem, int size, int flags)
192 {
193 	struct inpcb *inp;
194 
195 	inp = mem;
196 	INP_LOCK_INIT(inp, "inp", "udpliteinp");
197 	return (0);
198 }
199 
200 void
201 udp_init(void)
202 {
203 
204 	/*
205 	 * For now default to 2-tuple UDP hashing - until the fragment
206 	 * reassembly code can also update the flowid.
207 	 *
208 	 * Once we can calculate the flowid that way and re-establish
209 	 * a 4-tuple, flip this to 4-tuple.
210 	 */
211 	in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE,
212 	    "udp_inpcb", udp_inpcb_init, NULL, 0,
213 	    IPI_HASHFIELDS_2TUPLE);
214 	V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
215 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
216 	uma_zone_set_max(V_udpcb_zone, maxsockets);
217 	uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
218 	EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
219 	    EVENTHANDLER_PRI_ANY);
220 }
221 
222 void
223 udplite_init(void)
224 {
225 
226 	in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE,
227 	    UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init, NULL,
228 	    0, IPI_HASHFIELDS_2TUPLE);
229 }
230 
231 /*
232  * Kernel module interface for updating udpstat.  The argument is an index
233  * into udpstat treated as an array of u_long.  While this encodes the
234  * general layout of udpstat into the caller, it doesn't encode its location,
235  * so that future changes to add, for example, per-CPU stats support won't
236  * cause binary compatibility problems for kernel modules.
237  */
238 void
239 kmod_udpstat_inc(int statnum)
240 {
241 
242 	counter_u64_add(VNET(udpstat)[statnum], 1);
243 }
244 
245 int
246 udp_newudpcb(struct inpcb *inp)
247 {
248 	struct udpcb *up;
249 
250 	up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
251 	if (up == NULL)
252 		return (ENOBUFS);
253 	inp->inp_ppcb = up;
254 	return (0);
255 }
256 
257 void
258 udp_discardcb(struct udpcb *up)
259 {
260 
261 	uma_zfree(V_udpcb_zone, up);
262 }
263 
264 #ifdef VIMAGE
265 static void
266 udp_destroy(void *unused __unused)
267 {
268 
269 	in_pcbinfo_destroy(&V_udbinfo);
270 	uma_zdestroy(V_udpcb_zone);
271 }
272 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
273 
274 static void
275 udplite_destroy(void *unused __unused)
276 {
277 
278 	in_pcbinfo_destroy(&V_ulitecbinfo);
279 }
280 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
281     NULL);
282 #endif
283 
284 #ifdef INET
285 /*
286  * Subroutine of udp_input(), which appends the provided mbuf chain to the
287  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
288  * contains the source address.  If the socket ends up being an IPv6 socket,
289  * udp_append() will convert to a sockaddr_in6 before passing the address
290  * into the socket code.
291  *
292  * In the normal case udp_append() will return 0, indicating that you
293  * must unlock the inp. However if a tunneling protocol is in place we increment
294  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
295  * then decrement the reference count. If the inp_rele returns 1, indicating the
296  * inp is gone, we return that to the caller to tell them *not* to unlock
297  * the inp. In the case of multi-cast this will cause the distribution
298  * to stop (though most tunneling protocols known currently do *not* use
299  * multicast).
300  */
301 static int
302 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
303     struct sockaddr_in *udp_in)
304 {
305 	struct sockaddr *append_sa;
306 	struct socket *so;
307 	struct mbuf *tmpopts, *opts = NULL;
308 #ifdef INET6
309 	struct sockaddr_in6 udp_in6;
310 #endif
311 	struct udpcb *up;
312 
313 	INP_LOCK_ASSERT(inp);
314 
315 	/*
316 	 * Engage the tunneling protocol.
317 	 */
318 	up = intoudpcb(inp);
319 	if (up->u_tun_func != NULL) {
320 		in_pcbref(inp);
321 		INP_RUNLOCK(inp);
322 		(*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
323 		    up->u_tun_ctx);
324 		INP_RLOCK(inp);
325 		return (in_pcbrele_rlocked(inp));
326 	}
327 
328 	off += sizeof(struct udphdr);
329 
330 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
331 	/* Check AH/ESP integrity. */
332 	if (IPSEC_ENABLED(ipv4) &&
333 	    IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
334 		m_freem(n);
335 		return (0);
336 	}
337 	if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
338 		if (IPSEC_ENABLED(ipv4) &&
339 		    UDPENCAP_INPUT(n, off, AF_INET) != 0)
340 			return (0);	/* Consumed. */
341 	}
342 #endif /* IPSEC */
343 #ifdef MAC
344 	if (mac_inpcb_check_deliver(inp, n) != 0) {
345 		m_freem(n);
346 		return (0);
347 	}
348 #endif /* MAC */
349 	if (inp->inp_flags & INP_CONTROLOPTS ||
350 	    inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
351 #ifdef INET6
352 		if (inp->inp_vflag & INP_IPV6)
353 			(void)ip6_savecontrol_v4(inp, n, &opts, NULL);
354 		else
355 #endif /* INET6 */
356 			ip_savecontrol(inp, &opts, ip, n);
357 	}
358 	if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
359 		tmpopts = sbcreatecontrol((caddr_t)&udp_in[1],
360 			sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP);
361 		if (tmpopts) {
362 			if (opts) {
363 				tmpopts->m_next = opts;
364 				opts = tmpopts;
365 			} else
366 				opts = tmpopts;
367 		}
368 	}
369 #ifdef INET6
370 	if (inp->inp_vflag & INP_IPV6) {
371 		bzero(&udp_in6, sizeof(udp_in6));
372 		udp_in6.sin6_len = sizeof(udp_in6);
373 		udp_in6.sin6_family = AF_INET6;
374 		in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
375 		append_sa = (struct sockaddr *)&udp_in6;
376 	} else
377 #endif /* INET6 */
378 		append_sa = (struct sockaddr *)&udp_in[0];
379 	m_adj(n, off);
380 
381 	so = inp->inp_socket;
382 	SOCKBUF_LOCK(&so->so_rcv);
383 	if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
384 		SOCKBUF_UNLOCK(&so->so_rcv);
385 		m_freem(n);
386 		if (opts)
387 			m_freem(opts);
388 		UDPSTAT_INC(udps_fullsock);
389 	} else
390 		sorwakeup_locked(so);
391 	return (0);
392 }
393 
394 int
395 udp_input(struct mbuf **mp, int *offp, int proto)
396 {
397 	struct ip *ip;
398 	struct udphdr *uh;
399 	struct ifnet *ifp;
400 	struct inpcb *inp;
401 	uint16_t len, ip_len;
402 	struct inpcbinfo *pcbinfo;
403 	struct ip save_ip;
404 	struct sockaddr_in udp_in[2];
405 	struct mbuf *m;
406 	struct m_tag *fwd_tag;
407 	int cscov_partial, iphlen;
408 
409 	m = *mp;
410 	iphlen = *offp;
411 	ifp = m->m_pkthdr.rcvif;
412 	*mp = NULL;
413 	UDPSTAT_INC(udps_ipackets);
414 
415 	/*
416 	 * Strip IP options, if any; should skip this, make available to
417 	 * user, and use on returned packets, but we don't yet have a way to
418 	 * check the checksum with options still present.
419 	 */
420 	if (iphlen > sizeof (struct ip)) {
421 		ip_stripoptions(m);
422 		iphlen = sizeof(struct ip);
423 	}
424 
425 	/*
426 	 * Get IP and UDP header together in first mbuf.
427 	 */
428 	ip = mtod(m, struct ip *);
429 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
430 		if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
431 			UDPSTAT_INC(udps_hdrops);
432 			return (IPPROTO_DONE);
433 		}
434 		ip = mtod(m, struct ip *);
435 	}
436 	uh = (struct udphdr *)((caddr_t)ip + iphlen);
437 	cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
438 
439 	/*
440 	 * Destination port of 0 is illegal, based on RFC768.
441 	 */
442 	if (uh->uh_dport == 0)
443 		goto badunlocked;
444 
445 	/*
446 	 * Construct sockaddr format source address.  Stuff source address
447 	 * and datagram in user buffer.
448 	 */
449 	bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
450 	udp_in[0].sin_len = sizeof(struct sockaddr_in);
451 	udp_in[0].sin_family = AF_INET;
452 	udp_in[0].sin_port = uh->uh_sport;
453 	udp_in[0].sin_addr = ip->ip_src;
454 	udp_in[1].sin_len = sizeof(struct sockaddr_in);
455 	udp_in[1].sin_family = AF_INET;
456 	udp_in[1].sin_port = uh->uh_dport;
457 	udp_in[1].sin_addr = ip->ip_dst;
458 
459 	/*
460 	 * Make mbuf data length reflect UDP length.  If not enough data to
461 	 * reflect UDP length, drop.
462 	 */
463 	len = ntohs((u_short)uh->uh_ulen);
464 	ip_len = ntohs(ip->ip_len) - iphlen;
465 	if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
466 		/* Zero means checksum over the complete packet. */
467 		if (len == 0)
468 			len = ip_len;
469 		cscov_partial = 0;
470 	}
471 	if (ip_len != len) {
472 		if (len > ip_len || len < sizeof(struct udphdr)) {
473 			UDPSTAT_INC(udps_badlen);
474 			goto badunlocked;
475 		}
476 		if (proto == IPPROTO_UDP)
477 			m_adj(m, len - ip_len);
478 	}
479 
480 	/*
481 	 * Save a copy of the IP header in case we want restore it for
482 	 * sending an ICMP error message in response.
483 	 */
484 	if (!V_udp_blackhole)
485 		save_ip = *ip;
486 	else
487 		memset(&save_ip, 0, sizeof(save_ip));
488 
489 	/*
490 	 * Checksum extended UDP header and data.
491 	 */
492 	if (uh->uh_sum) {
493 		u_short uh_sum;
494 
495 		if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
496 		    !cscov_partial) {
497 			if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
498 				uh_sum = m->m_pkthdr.csum_data;
499 			else
500 				uh_sum = in_pseudo(ip->ip_src.s_addr,
501 				    ip->ip_dst.s_addr, htonl((u_short)len +
502 				    m->m_pkthdr.csum_data + proto));
503 			uh_sum ^= 0xffff;
504 		} else {
505 			char b[9];
506 
507 			bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
508 			bzero(((struct ipovly *)ip)->ih_x1, 9);
509 			((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
510 			    uh->uh_ulen : htons(ip_len);
511 			uh_sum = in_cksum(m, len + sizeof (struct ip));
512 			bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
513 		}
514 		if (uh_sum) {
515 			UDPSTAT_INC(udps_badsum);
516 			m_freem(m);
517 			return (IPPROTO_DONE);
518 		}
519 	} else {
520 		if (proto == IPPROTO_UDP) {
521 			UDPSTAT_INC(udps_nosum);
522 		} else {
523 			/* UDPLite requires a checksum */
524 			/* XXX: What is the right UDPLite MIB counter here? */
525 			m_freem(m);
526 			return (IPPROTO_DONE);
527 		}
528 	}
529 
530 	pcbinfo = udp_get_inpcbinfo(proto);
531 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
532 	    ((!V_udp_require_l2_bcast || m->m_flags & M_BCAST) &&
533 	    in_broadcast(ip->ip_dst, ifp))) {
534 		struct inpcb *last;
535 		struct inpcbhead *pcblist;
536 		struct ip_moptions *imo;
537 
538 		INP_INFO_RLOCK(pcbinfo);
539 		pcblist = udp_get_pcblist(proto);
540 		last = NULL;
541 		LIST_FOREACH(inp, pcblist, inp_list) {
542 			if (inp->inp_lport != uh->uh_dport)
543 				continue;
544 #ifdef INET6
545 			if ((inp->inp_vflag & INP_IPV4) == 0)
546 				continue;
547 #endif
548 			if (inp->inp_laddr.s_addr != INADDR_ANY &&
549 			    inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
550 				continue;
551 			if (inp->inp_faddr.s_addr != INADDR_ANY &&
552 			    inp->inp_faddr.s_addr != ip->ip_src.s_addr)
553 				continue;
554 			if (inp->inp_fport != 0 &&
555 			    inp->inp_fport != uh->uh_sport)
556 				continue;
557 
558 			INP_RLOCK(inp);
559 
560 			/*
561 			 * XXXRW: Because we weren't holding either the inpcb
562 			 * or the hash lock when we checked for a match
563 			 * before, we should probably recheck now that the
564 			 * inpcb lock is held.
565 			 */
566 
567 			/*
568 			 * Handle socket delivery policy for any-source
569 			 * and source-specific multicast. [RFC3678]
570 			 */
571 			imo = inp->inp_moptions;
572 			if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
573 				struct sockaddr_in	 group;
574 				int			 blocked;
575 				if (imo == NULL) {
576 					INP_RUNLOCK(inp);
577 					continue;
578 				}
579 				bzero(&group, sizeof(struct sockaddr_in));
580 				group.sin_len = sizeof(struct sockaddr_in);
581 				group.sin_family = AF_INET;
582 				group.sin_addr = ip->ip_dst;
583 
584 				blocked = imo_multi_filter(imo, ifp,
585 					(struct sockaddr *)&group,
586 					(struct sockaddr *)&udp_in[0]);
587 				if (blocked != MCAST_PASS) {
588 					if (blocked == MCAST_NOTGMEMBER)
589 						IPSTAT_INC(ips_notmember);
590 					if (blocked == MCAST_NOTSMEMBER ||
591 					    blocked == MCAST_MUTED)
592 						UDPSTAT_INC(udps_filtermcast);
593 					INP_RUNLOCK(inp);
594 					continue;
595 				}
596 			}
597 			if (last != NULL) {
598 				struct mbuf *n;
599 
600 				if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
601 				    NULL) {
602 					UDP_PROBE(receive, NULL, last, ip,
603 					    last, uh);
604 					if (udp_append(last, ip, n, iphlen,
605 						udp_in)) {
606 						goto inp_lost;
607 					}
608 				}
609 				INP_RUNLOCK(last);
610 			}
611 			last = inp;
612 			/*
613 			 * Don't look for additional matches if this one does
614 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
615 			 * socket options set.  This heuristic avoids
616 			 * searching through all pcbs in the common case of a
617 			 * non-shared port.  It assumes that an application
618 			 * will never clear these options after setting them.
619 			 */
620 			if ((last->inp_socket->so_options &
621 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
622 				break;
623 		}
624 
625 		if (last == NULL) {
626 			/*
627 			 * No matching pcb found; discard datagram.  (No need
628 			 * to send an ICMP Port Unreachable for a broadcast
629 			 * or multicast datgram.)
630 			 */
631 			UDPSTAT_INC(udps_noportbcast);
632 			if (inp)
633 				INP_RUNLOCK(inp);
634 			INP_INFO_RUNLOCK(pcbinfo);
635 			goto badunlocked;
636 		}
637 		UDP_PROBE(receive, NULL, last, ip, last, uh);
638 		if (udp_append(last, ip, m, iphlen, udp_in) == 0)
639 			INP_RUNLOCK(last);
640 	inp_lost:
641 		INP_INFO_RUNLOCK(pcbinfo);
642 		return (IPPROTO_DONE);
643 	}
644 
645 	/*
646 	 * Locate pcb for datagram.
647 	 */
648 
649 	/*
650 	 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
651 	 */
652 	if ((m->m_flags & M_IP_NEXTHOP) &&
653 	    (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
654 		struct sockaddr_in *next_hop;
655 
656 		next_hop = (struct sockaddr_in *)(fwd_tag + 1);
657 
658 		/*
659 		 * Transparently forwarded. Pretend to be the destination.
660 		 * Already got one like this?
661 		 */
662 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
663 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
664 		if (!inp) {
665 			/*
666 			 * It's new.  Try to find the ambushing socket.
667 			 * Because we've rewritten the destination address,
668 			 * any hardware-generated hash is ignored.
669 			 */
670 			inp = in_pcblookup(pcbinfo, ip->ip_src,
671 			    uh->uh_sport, next_hop->sin_addr,
672 			    next_hop->sin_port ? htons(next_hop->sin_port) :
673 			    uh->uh_dport, INPLOOKUP_WILDCARD |
674 			    INPLOOKUP_RLOCKPCB, ifp);
675 		}
676 		/* Remove the tag from the packet. We don't need it anymore. */
677 		m_tag_delete(m, fwd_tag);
678 		m->m_flags &= ~M_IP_NEXTHOP;
679 	} else
680 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
681 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
682 		    INPLOOKUP_RLOCKPCB, ifp, m);
683 	if (inp == NULL) {
684 		if (udp_log_in_vain) {
685 			char src[INET_ADDRSTRLEN];
686 			char dst[INET_ADDRSTRLEN];
687 
688 			log(LOG_INFO,
689 			    "Connection attempt to UDP %s:%d from %s:%d\n",
690 			    inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
691 			    inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
692 		}
693 		UDPSTAT_INC(udps_noport);
694 		if (m->m_flags & (M_BCAST | M_MCAST)) {
695 			UDPSTAT_INC(udps_noportbcast);
696 			goto badunlocked;
697 		}
698 		if (V_udp_blackhole)
699 			goto badunlocked;
700 		if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
701 			goto badunlocked;
702 		*ip = save_ip;
703 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
704 		return (IPPROTO_DONE);
705 	}
706 
707 	/*
708 	 * Check the minimum TTL for socket.
709 	 */
710 	INP_RLOCK_ASSERT(inp);
711 	if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
712 		INP_RUNLOCK(inp);
713 		m_freem(m);
714 		return (IPPROTO_DONE);
715 	}
716 	if (cscov_partial) {
717 		struct udpcb *up;
718 
719 		up = intoudpcb(inp);
720 		if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
721 			INP_RUNLOCK(inp);
722 			m_freem(m);
723 			return (IPPROTO_DONE);
724 		}
725 	}
726 
727 	UDP_PROBE(receive, NULL, inp, ip, inp, uh);
728 	if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
729 		INP_RUNLOCK(inp);
730 	return (IPPROTO_DONE);
731 
732 badunlocked:
733 	m_freem(m);
734 	return (IPPROTO_DONE);
735 }
736 #endif /* INET */
737 
738 /*
739  * Notify a udp user of an asynchronous error; just wake up so that they can
740  * collect error status.
741  */
742 struct inpcb *
743 udp_notify(struct inpcb *inp, int errno)
744 {
745 
746 	/*
747 	 * While udp_ctlinput() always calls udp_notify() with a read lock
748 	 * when invoking it directly, in_pcbnotifyall() currently uses write
749 	 * locks due to sharing code with TCP.  For now, accept either a read
750 	 * or a write lock, but a read lock is sufficient.
751 	 */
752 	INP_LOCK_ASSERT(inp);
753 	if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
754 	     errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
755 		RTFREE(inp->inp_route.ro_rt);
756 		inp->inp_route.ro_rt = (struct rtentry *)NULL;
757 	}
758 
759 	inp->inp_socket->so_error = errno;
760 	sorwakeup(inp->inp_socket);
761 	sowwakeup(inp->inp_socket);
762 	return (inp);
763 }
764 
765 #ifdef INET
766 static void
767 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
768     struct inpcbinfo *pcbinfo)
769 {
770 	struct ip *ip = vip;
771 	struct udphdr *uh;
772 	struct in_addr faddr;
773 	struct inpcb *inp;
774 
775 	faddr = ((struct sockaddr_in *)sa)->sin_addr;
776 	if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
777 		return;
778 
779 	if (PRC_IS_REDIRECT(cmd)) {
780 		/* signal EHOSTDOWN, as it flushes the cached route */
781 		in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
782 		return;
783 	}
784 
785 	/*
786 	 * Hostdead is ugly because it goes linearly through all PCBs.
787 	 *
788 	 * XXX: We never get this from ICMP, otherwise it makes an excellent
789 	 * DoS attack on machines with many connections.
790 	 */
791 	if (cmd == PRC_HOSTDEAD)
792 		ip = NULL;
793 	else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
794 		return;
795 	if (ip != NULL) {
796 		uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
797 		inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
798 		    ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL);
799 		if (inp != NULL) {
800 			INP_RLOCK_ASSERT(inp);
801 			if (inp->inp_socket != NULL) {
802 				udp_notify(inp, inetctlerrmap[cmd]);
803 			}
804 			INP_RUNLOCK(inp);
805 		} else {
806 			inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
807 					   ip->ip_src, uh->uh_sport,
808 					   INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
809 			if (inp != NULL) {
810 				struct udpcb *up;
811 
812 				up = intoudpcb(inp);
813 				if (up->u_icmp_func != NULL) {
814 					INP_RUNLOCK(inp);
815 					(*up->u_icmp_func)(cmd, sa, vip, up->u_tun_ctx);
816 				} else {
817 					INP_RUNLOCK(inp);
818 				}
819 			}
820 		}
821 	} else
822 		in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
823 		    udp_notify);
824 }
825 void
826 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
827 {
828 
829 	return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
830 }
831 
832 void
833 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
834 {
835 
836 	return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
837 }
838 #endif /* INET */
839 
840 static int
841 udp_pcblist(SYSCTL_HANDLER_ARGS)
842 {
843 	int error, i, n;
844 	struct inpcb *inp, **inp_list;
845 	inp_gen_t gencnt;
846 	struct xinpgen xig;
847 
848 	/*
849 	 * The process of preparing the PCB list is too time-consuming and
850 	 * resource-intensive to repeat twice on every request.
851 	 */
852 	if (req->oldptr == 0) {
853 		n = V_udbinfo.ipi_count;
854 		n += imax(n / 8, 10);
855 		req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
856 		return (0);
857 	}
858 
859 	if (req->newptr != 0)
860 		return (EPERM);
861 
862 	/*
863 	 * OK, now we're committed to doing something.
864 	 */
865 	INP_INFO_RLOCK(&V_udbinfo);
866 	gencnt = V_udbinfo.ipi_gencnt;
867 	n = V_udbinfo.ipi_count;
868 	INP_INFO_RUNLOCK(&V_udbinfo);
869 
870 	error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
871 		+ n * sizeof(struct xinpcb));
872 	if (error != 0)
873 		return (error);
874 
875 	xig.xig_len = sizeof xig;
876 	xig.xig_count = n;
877 	xig.xig_gen = gencnt;
878 	xig.xig_sogen = so_gencnt;
879 	error = SYSCTL_OUT(req, &xig, sizeof xig);
880 	if (error)
881 		return (error);
882 
883 	inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
884 	if (inp_list == NULL)
885 		return (ENOMEM);
886 
887 	INP_INFO_RLOCK(&V_udbinfo);
888 	for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
889 	     inp = LIST_NEXT(inp, inp_list)) {
890 		INP_WLOCK(inp);
891 		if (inp->inp_gencnt <= gencnt &&
892 		    cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
893 			in_pcbref(inp);
894 			inp_list[i++] = inp;
895 		}
896 		INP_WUNLOCK(inp);
897 	}
898 	INP_INFO_RUNLOCK(&V_udbinfo);
899 	n = i;
900 
901 	error = 0;
902 	for (i = 0; i < n; i++) {
903 		inp = inp_list[i];
904 		INP_RLOCK(inp);
905 		if (inp->inp_gencnt <= gencnt) {
906 			struct xinpcb xi;
907 
908 			bzero(&xi, sizeof(xi));
909 			xi.xi_len = sizeof xi;
910 			/* XXX should avoid extra copy */
911 			bcopy(inp, &xi.xi_inp, sizeof *inp);
912 			if (inp->inp_socket)
913 				sotoxsocket(inp->inp_socket, &xi.xi_socket);
914 			xi.xi_inp.inp_gencnt = inp->inp_gencnt;
915 			INP_RUNLOCK(inp);
916 			error = SYSCTL_OUT(req, &xi, sizeof xi);
917 		} else
918 			INP_RUNLOCK(inp);
919 	}
920 	INP_INFO_WLOCK(&V_udbinfo);
921 	for (i = 0; i < n; i++) {
922 		inp = inp_list[i];
923 		INP_RLOCK(inp);
924 		if (!in_pcbrele_rlocked(inp))
925 			INP_RUNLOCK(inp);
926 	}
927 	INP_INFO_WUNLOCK(&V_udbinfo);
928 
929 	if (!error) {
930 		/*
931 		 * Give the user an updated idea of our state.  If the
932 		 * generation differs from what we told her before, she knows
933 		 * that something happened while we were processing this
934 		 * request, and it might be necessary to retry.
935 		 */
936 		INP_INFO_RLOCK(&V_udbinfo);
937 		xig.xig_gen = V_udbinfo.ipi_gencnt;
938 		xig.xig_sogen = so_gencnt;
939 		xig.xig_count = V_udbinfo.ipi_count;
940 		INP_INFO_RUNLOCK(&V_udbinfo);
941 		error = SYSCTL_OUT(req, &xig, sizeof xig);
942 	}
943 	free(inp_list, M_TEMP);
944 	return (error);
945 }
946 
947 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
948     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
949     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
950 
951 #ifdef INET
952 static int
953 udp_getcred(SYSCTL_HANDLER_ARGS)
954 {
955 	struct xucred xuc;
956 	struct sockaddr_in addrs[2];
957 	struct inpcb *inp;
958 	int error;
959 
960 	error = priv_check(req->td, PRIV_NETINET_GETCRED);
961 	if (error)
962 		return (error);
963 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
964 	if (error)
965 		return (error);
966 	inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
967 	    addrs[0].sin_addr, addrs[0].sin_port,
968 	    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
969 	if (inp != NULL) {
970 		INP_RLOCK_ASSERT(inp);
971 		if (inp->inp_socket == NULL)
972 			error = ENOENT;
973 		if (error == 0)
974 			error = cr_canseeinpcb(req->td->td_ucred, inp);
975 		if (error == 0)
976 			cru2x(inp->inp_cred, &xuc);
977 		INP_RUNLOCK(inp);
978 	} else
979 		error = ENOENT;
980 	if (error == 0)
981 		error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
982 	return (error);
983 }
984 
985 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
986     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
987     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
988 #endif /* INET */
989 
990 int
991 udp_ctloutput(struct socket *so, struct sockopt *sopt)
992 {
993 	struct inpcb *inp;
994 	struct udpcb *up;
995 	int isudplite, error, optval;
996 
997 	error = 0;
998 	isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
999 	inp = sotoinpcb(so);
1000 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1001 	INP_WLOCK(inp);
1002 	if (sopt->sopt_level != so->so_proto->pr_protocol) {
1003 #ifdef INET6
1004 		if (INP_CHECK_SOCKAF(so, AF_INET6)) {
1005 			INP_WUNLOCK(inp);
1006 			error = ip6_ctloutput(so, sopt);
1007 		}
1008 #endif
1009 #if defined(INET) && defined(INET6)
1010 		else
1011 #endif
1012 #ifdef INET
1013 		{
1014 			INP_WUNLOCK(inp);
1015 			error = ip_ctloutput(so, sopt);
1016 		}
1017 #endif
1018 		return (error);
1019 	}
1020 
1021 	switch (sopt->sopt_dir) {
1022 	case SOPT_SET:
1023 		switch (sopt->sopt_name) {
1024 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1025 #ifdef INET
1026 		case UDP_ENCAP:
1027 			if (!IPSEC_ENABLED(ipv4)) {
1028 				INP_WUNLOCK(inp);
1029 				return (ENOPROTOOPT);
1030 			}
1031 			error = UDPENCAP_PCBCTL(inp, sopt);
1032 			break;
1033 #endif /* INET */
1034 #endif /* IPSEC */
1035 		case UDPLITE_SEND_CSCOV:
1036 		case UDPLITE_RECV_CSCOV:
1037 			if (!isudplite) {
1038 				INP_WUNLOCK(inp);
1039 				error = ENOPROTOOPT;
1040 				break;
1041 			}
1042 			INP_WUNLOCK(inp);
1043 			error = sooptcopyin(sopt, &optval, sizeof(optval),
1044 			    sizeof(optval));
1045 			if (error != 0)
1046 				break;
1047 			inp = sotoinpcb(so);
1048 			KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1049 			INP_WLOCK(inp);
1050 			up = intoudpcb(inp);
1051 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
1052 			if ((optval != 0 && optval < 8) || (optval > 65535)) {
1053 				INP_WUNLOCK(inp);
1054 				error = EINVAL;
1055 				break;
1056 			}
1057 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1058 				up->u_txcslen = optval;
1059 			else
1060 				up->u_rxcslen = optval;
1061 			INP_WUNLOCK(inp);
1062 			break;
1063 		default:
1064 			INP_WUNLOCK(inp);
1065 			error = ENOPROTOOPT;
1066 			break;
1067 		}
1068 		break;
1069 	case SOPT_GET:
1070 		switch (sopt->sopt_name) {
1071 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1072 #ifdef INET
1073 		case UDP_ENCAP:
1074 			if (!IPSEC_ENABLED(ipv4)) {
1075 				INP_WUNLOCK(inp);
1076 				return (ENOPROTOOPT);
1077 			}
1078 			error = UDPENCAP_PCBCTL(inp, sopt);
1079 			break;
1080 #endif /* INET */
1081 #endif /* IPSEC */
1082 		case UDPLITE_SEND_CSCOV:
1083 		case UDPLITE_RECV_CSCOV:
1084 			if (!isudplite) {
1085 				INP_WUNLOCK(inp);
1086 				error = ENOPROTOOPT;
1087 				break;
1088 			}
1089 			up = intoudpcb(inp);
1090 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
1091 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1092 				optval = up->u_txcslen;
1093 			else
1094 				optval = up->u_rxcslen;
1095 			INP_WUNLOCK(inp);
1096 			error = sooptcopyout(sopt, &optval, sizeof(optval));
1097 			break;
1098 		default:
1099 			INP_WUNLOCK(inp);
1100 			error = ENOPROTOOPT;
1101 			break;
1102 		}
1103 		break;
1104 	}
1105 	return (error);
1106 }
1107 
1108 #ifdef INET
1109 #define	UH_WLOCKED	2
1110 #define	UH_RLOCKED	1
1111 #define	UH_UNLOCKED	0
1112 static int
1113 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1114     struct mbuf *control, struct thread *td)
1115 {
1116 	struct udpiphdr *ui;
1117 	int len = m->m_pkthdr.len;
1118 	struct in_addr faddr, laddr;
1119 	struct cmsghdr *cm;
1120 	struct inpcbinfo *pcbinfo;
1121 	struct sockaddr_in *sin, src;
1122 	int cscov_partial = 0;
1123 	int error = 0;
1124 	int ipflags;
1125 	u_short fport, lport;
1126 	int unlock_udbinfo, unlock_inp;
1127 	u_char tos;
1128 	uint8_t pr;
1129 	uint16_t cscov = 0;
1130 	uint32_t flowid = 0;
1131 	uint8_t flowtype = M_HASHTYPE_NONE;
1132 
1133 	/*
1134 	 * udp_output() may need to temporarily bind or connect the current
1135 	 * inpcb.  As such, we don't know up front whether we will need the
1136 	 * pcbinfo lock or not.  Do any work to decide what is needed up
1137 	 * front before acquiring any locks.
1138 	 */
1139 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1140 		if (control)
1141 			m_freem(control);
1142 		m_freem(m);
1143 		return (EMSGSIZE);
1144 	}
1145 
1146 	src.sin_family = 0;
1147 	sin = (struct sockaddr_in *)addr;
1148 	if (sin == NULL ||
1149 	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1150 		INP_WLOCK(inp);
1151 		unlock_inp = UH_WLOCKED;
1152 	} else {
1153 		INP_RLOCK(inp);
1154 		unlock_inp = UH_RLOCKED;
1155 	}
1156 	tos = inp->inp_ip_tos;
1157 	if (control != NULL) {
1158 		/*
1159 		 * XXX: Currently, we assume all the optional information is
1160 		 * stored in a single mbuf.
1161 		 */
1162 		if (control->m_next) {
1163 			if (unlock_inp == UH_WLOCKED)
1164 				INP_WUNLOCK(inp);
1165 			else
1166 				INP_RUNLOCK(inp);
1167 			m_freem(control);
1168 			m_freem(m);
1169 			return (EINVAL);
1170 		}
1171 		for (; control->m_len > 0;
1172 		    control->m_data += CMSG_ALIGN(cm->cmsg_len),
1173 		    control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1174 			cm = mtod(control, struct cmsghdr *);
1175 			if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1176 			    || cm->cmsg_len > control->m_len) {
1177 				error = EINVAL;
1178 				break;
1179 			}
1180 			if (cm->cmsg_level != IPPROTO_IP)
1181 				continue;
1182 
1183 			switch (cm->cmsg_type) {
1184 			case IP_SENDSRCADDR:
1185 				if (cm->cmsg_len !=
1186 				    CMSG_LEN(sizeof(struct in_addr))) {
1187 					error = EINVAL;
1188 					break;
1189 				}
1190 				bzero(&src, sizeof(src));
1191 				src.sin_family = AF_INET;
1192 				src.sin_len = sizeof(src);
1193 				src.sin_port = inp->inp_lport;
1194 				src.sin_addr =
1195 				    *(struct in_addr *)CMSG_DATA(cm);
1196 				break;
1197 
1198 			case IP_TOS:
1199 				if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1200 					error = EINVAL;
1201 					break;
1202 				}
1203 				tos = *(u_char *)CMSG_DATA(cm);
1204 				break;
1205 
1206 			case IP_FLOWID:
1207 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1208 					error = EINVAL;
1209 					break;
1210 				}
1211 				flowid = *(uint32_t *) CMSG_DATA(cm);
1212 				break;
1213 
1214 			case IP_FLOWTYPE:
1215 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1216 					error = EINVAL;
1217 					break;
1218 				}
1219 				flowtype = *(uint32_t *) CMSG_DATA(cm);
1220 				break;
1221 
1222 #ifdef	RSS
1223 			case IP_RSSBUCKETID:
1224 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1225 					error = EINVAL;
1226 					break;
1227 				}
1228 				/* This is just a placeholder for now */
1229 				break;
1230 #endif	/* RSS */
1231 			default:
1232 				error = ENOPROTOOPT;
1233 				break;
1234 			}
1235 			if (error)
1236 				break;
1237 		}
1238 		m_freem(control);
1239 	}
1240 	if (error) {
1241 		if (unlock_inp == UH_WLOCKED)
1242 			INP_WUNLOCK(inp);
1243 		else
1244 			INP_RUNLOCK(inp);
1245 		m_freem(m);
1246 		return (error);
1247 	}
1248 
1249 	/*
1250 	 * Depending on whether or not the application has bound or connected
1251 	 * the socket, we may have to do varying levels of work.  The optimal
1252 	 * case is for a connected UDP socket, as a global lock isn't
1253 	 * required at all.
1254 	 *
1255 	 * In order to decide which we need, we require stability of the
1256 	 * inpcb binding, which we ensure by acquiring a read lock on the
1257 	 * inpcb.  This doesn't strictly follow the lock order, so we play
1258 	 * the trylock and retry game; note that we may end up with more
1259 	 * conservative locks than required the second time around, so later
1260 	 * assertions have to accept that.  Further analysis of the number of
1261 	 * misses under contention is required.
1262 	 *
1263 	 * XXXRW: Check that hash locking update here is correct.
1264 	 */
1265 	pr = inp->inp_socket->so_proto->pr_protocol;
1266 	pcbinfo = udp_get_inpcbinfo(pr);
1267 	sin = (struct sockaddr_in *)addr;
1268 	if (sin != NULL &&
1269 	    (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1270 		INP_HASH_WLOCK(pcbinfo);
1271 		unlock_udbinfo = UH_WLOCKED;
1272 	} else if ((sin != NULL && (
1273 	    (sin->sin_addr.s_addr == INADDR_ANY) ||
1274 	    (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
1275 	    (inp->inp_laddr.s_addr == INADDR_ANY) ||
1276 	    (inp->inp_lport == 0))) ||
1277 	    (src.sin_family == AF_INET)) {
1278 		INP_HASH_RLOCK(pcbinfo);
1279 		unlock_udbinfo = UH_RLOCKED;
1280 	} else
1281 		unlock_udbinfo = UH_UNLOCKED;
1282 
1283 	/*
1284 	 * If the IP_SENDSRCADDR control message was specified, override the
1285 	 * source address for this datagram.  Its use is invalidated if the
1286 	 * address thus specified is incomplete or clobbers other inpcbs.
1287 	 */
1288 	laddr = inp->inp_laddr;
1289 	lport = inp->inp_lport;
1290 	if (src.sin_family == AF_INET) {
1291 		INP_HASH_LOCK_ASSERT(pcbinfo);
1292 		if ((lport == 0) ||
1293 		    (laddr.s_addr == INADDR_ANY &&
1294 		     src.sin_addr.s_addr == INADDR_ANY)) {
1295 			error = EINVAL;
1296 			goto release;
1297 		}
1298 		error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1299 		    &laddr.s_addr, &lport, td->td_ucred);
1300 		if (error)
1301 			goto release;
1302 	}
1303 
1304 	/*
1305 	 * If a UDP socket has been connected, then a local address/port will
1306 	 * have been selected and bound.
1307 	 *
1308 	 * If a UDP socket has not been connected to, then an explicit
1309 	 * destination address must be used, in which case a local
1310 	 * address/port may not have been selected and bound.
1311 	 */
1312 	if (sin != NULL) {
1313 		INP_LOCK_ASSERT(inp);
1314 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
1315 			error = EISCONN;
1316 			goto release;
1317 		}
1318 
1319 		/*
1320 		 * Jail may rewrite the destination address, so let it do
1321 		 * that before we use it.
1322 		 */
1323 		error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1324 		if (error)
1325 			goto release;
1326 
1327 		/*
1328 		 * If a local address or port hasn't yet been selected, or if
1329 		 * the destination address needs to be rewritten due to using
1330 		 * a special INADDR_ constant, invoke in_pcbconnect_setup()
1331 		 * to do the heavy lifting.  Once a port is selected, we
1332 		 * commit the binding back to the socket; we also commit the
1333 		 * binding of the address if in jail.
1334 		 *
1335 		 * If we already have a valid binding and we're not
1336 		 * requesting a destination address rewrite, use a fast path.
1337 		 */
1338 		if (inp->inp_laddr.s_addr == INADDR_ANY ||
1339 		    inp->inp_lport == 0 ||
1340 		    sin->sin_addr.s_addr == INADDR_ANY ||
1341 		    sin->sin_addr.s_addr == INADDR_BROADCAST) {
1342 			INP_HASH_LOCK_ASSERT(pcbinfo);
1343 			error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1344 			    &lport, &faddr.s_addr, &fport, NULL,
1345 			    td->td_ucred);
1346 			if (error)
1347 				goto release;
1348 
1349 			/*
1350 			 * XXXRW: Why not commit the port if the address is
1351 			 * !INADDR_ANY?
1352 			 */
1353 			/* Commit the local port if newly assigned. */
1354 			if (inp->inp_laddr.s_addr == INADDR_ANY &&
1355 			    inp->inp_lport == 0) {
1356 				INP_WLOCK_ASSERT(inp);
1357 				INP_HASH_WLOCK_ASSERT(pcbinfo);
1358 				/*
1359 				 * Remember addr if jailed, to prevent
1360 				 * rebinding.
1361 				 */
1362 				if (prison_flag(td->td_ucred, PR_IP4))
1363 					inp->inp_laddr = laddr;
1364 				inp->inp_lport = lport;
1365 				if (in_pcbinshash(inp) != 0) {
1366 					inp->inp_lport = 0;
1367 					error = EAGAIN;
1368 					goto release;
1369 				}
1370 				inp->inp_flags |= INP_ANONPORT;
1371 			}
1372 		} else {
1373 			faddr = sin->sin_addr;
1374 			fport = sin->sin_port;
1375 		}
1376 	} else {
1377 		INP_LOCK_ASSERT(inp);
1378 		faddr = inp->inp_faddr;
1379 		fport = inp->inp_fport;
1380 		if (faddr.s_addr == INADDR_ANY) {
1381 			error = ENOTCONN;
1382 			goto release;
1383 		}
1384 	}
1385 
1386 	/*
1387 	 * Calculate data length and get a mbuf for UDP, IP, and possible
1388 	 * link-layer headers.  Immediate slide the data pointer back forward
1389 	 * since we won't use that space at this layer.
1390 	 */
1391 	M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1392 	if (m == NULL) {
1393 		error = ENOBUFS;
1394 		goto release;
1395 	}
1396 	m->m_data += max_linkhdr;
1397 	m->m_len -= max_linkhdr;
1398 	m->m_pkthdr.len -= max_linkhdr;
1399 
1400 	/*
1401 	 * Fill in mbuf with extended UDP header and addresses and length put
1402 	 * into network format.
1403 	 */
1404 	ui = mtod(m, struct udpiphdr *);
1405 	bzero(ui->ui_x1, sizeof(ui->ui_x1));	/* XXX still needed? */
1406 	ui->ui_pr = pr;
1407 	ui->ui_src = laddr;
1408 	ui->ui_dst = faddr;
1409 	ui->ui_sport = lport;
1410 	ui->ui_dport = fport;
1411 	ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1412 	if (pr == IPPROTO_UDPLITE) {
1413 		struct udpcb *up;
1414 		uint16_t plen;
1415 
1416 		up = intoudpcb(inp);
1417 		cscov = up->u_txcslen;
1418 		plen = (u_short)len + sizeof(struct udphdr);
1419 		if (cscov >= plen)
1420 			cscov = 0;
1421 		ui->ui_len = htons(plen);
1422 		ui->ui_ulen = htons(cscov);
1423 		/*
1424 		 * For UDP-Lite, checksum coverage length of zero means
1425 		 * the entire UDPLite packet is covered by the checksum.
1426 		 */
1427 		cscov_partial = (cscov == 0) ? 0 : 1;
1428 	} else
1429 		ui->ui_v = IPVERSION << 4;
1430 
1431 	/*
1432 	 * Set the Don't Fragment bit in the IP header.
1433 	 */
1434 	if (inp->inp_flags & INP_DONTFRAG) {
1435 		struct ip *ip;
1436 
1437 		ip = (struct ip *)&ui->ui_i;
1438 		ip->ip_off |= htons(IP_DF);
1439 	}
1440 
1441 	ipflags = 0;
1442 	if (inp->inp_socket->so_options & SO_DONTROUTE)
1443 		ipflags |= IP_ROUTETOIF;
1444 	if (inp->inp_socket->so_options & SO_BROADCAST)
1445 		ipflags |= IP_ALLOWBROADCAST;
1446 	if (inp->inp_flags & INP_ONESBCAST)
1447 		ipflags |= IP_SENDONES;
1448 
1449 #ifdef MAC
1450 	mac_inpcb_create_mbuf(inp, m);
1451 #endif
1452 
1453 	/*
1454 	 * Set up checksum and output datagram.
1455 	 */
1456 	ui->ui_sum = 0;
1457 	if (pr == IPPROTO_UDPLITE) {
1458 		if (inp->inp_flags & INP_ONESBCAST)
1459 			faddr.s_addr = INADDR_BROADCAST;
1460 		if (cscov_partial) {
1461 			if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1462 				ui->ui_sum = 0xffff;
1463 		} else {
1464 			if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1465 				ui->ui_sum = 0xffff;
1466 		}
1467 	} else if (V_udp_cksum) {
1468 		if (inp->inp_flags & INP_ONESBCAST)
1469 			faddr.s_addr = INADDR_BROADCAST;
1470 		ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1471 		    htons((u_short)len + sizeof(struct udphdr) + pr));
1472 		m->m_pkthdr.csum_flags = CSUM_UDP;
1473 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1474 	}
1475 	((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1476 	((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;	/* XXX */
1477 	((struct ip *)ui)->ip_tos = tos;		/* XXX */
1478 	UDPSTAT_INC(udps_opackets);
1479 
1480 	/*
1481 	 * Setup flowid / RSS information for outbound socket.
1482 	 *
1483 	 * Once the UDP code decides to set a flowid some other way,
1484 	 * this allows the flowid to be overridden by userland.
1485 	 */
1486 	if (flowtype != M_HASHTYPE_NONE) {
1487 		m->m_pkthdr.flowid = flowid;
1488 		M_HASHTYPE_SET(m, flowtype);
1489 #ifdef	RSS
1490 	} else {
1491 		uint32_t hash_val, hash_type;
1492 		/*
1493 		 * Calculate an appropriate RSS hash for UDP and
1494 		 * UDP Lite.
1495 		 *
1496 		 * The called function will take care of figuring out
1497 		 * whether a 2-tuple or 4-tuple hash is required based
1498 		 * on the currently configured scheme.
1499 		 *
1500 		 * Later later on connected socket values should be
1501 		 * cached in the inpcb and reused, rather than constantly
1502 		 * re-calculating it.
1503 		 *
1504 		 * UDP Lite is a different protocol number and will
1505 		 * likely end up being hashed as a 2-tuple until
1506 		 * RSS / NICs grow UDP Lite protocol awareness.
1507 		 */
1508 		if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1509 		    pr, &hash_val, &hash_type) == 0) {
1510 			m->m_pkthdr.flowid = hash_val;
1511 			M_HASHTYPE_SET(m, hash_type);
1512 		}
1513 #endif
1514 	}
1515 
1516 #ifdef	RSS
1517 	/*
1518 	 * Don't override with the inp cached flowid value.
1519 	 *
1520 	 * Depending upon the kind of send being done, the inp
1521 	 * flowid/flowtype values may actually not be appropriate
1522 	 * for this particular socket send.
1523 	 *
1524 	 * We should either leave the flowid at zero (which is what is
1525 	 * currently done) or set it to some software generated
1526 	 * hash value based on the packet contents.
1527 	 */
1528 	ipflags |= IP_NODEFAULTFLOWID;
1529 #endif	/* RSS */
1530 
1531 	if (unlock_udbinfo == UH_WLOCKED)
1532 		INP_HASH_WUNLOCK(pcbinfo);
1533 	else if (unlock_udbinfo == UH_RLOCKED)
1534 		INP_HASH_RUNLOCK(pcbinfo);
1535 	UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1536 	error = ip_output(m, inp->inp_options,
1537 	    (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
1538 	    inp->inp_moptions, inp);
1539 	if (unlock_inp == UH_WLOCKED)
1540 		INP_WUNLOCK(inp);
1541 	else
1542 		INP_RUNLOCK(inp);
1543 	return (error);
1544 
1545 release:
1546 	if (unlock_udbinfo == UH_WLOCKED) {
1547 		KASSERT(unlock_inp == UH_WLOCKED,
1548 		    ("%s: excl udbinfo lock, shared inp lock", __func__));
1549 		INP_HASH_WUNLOCK(pcbinfo);
1550 		INP_WUNLOCK(inp);
1551 	} else if (unlock_udbinfo == UH_RLOCKED) {
1552 		KASSERT(unlock_inp == UH_RLOCKED,
1553 		    ("%s: shared udbinfo lock, excl inp lock", __func__));
1554 		INP_HASH_RUNLOCK(pcbinfo);
1555 		INP_RUNLOCK(inp);
1556 	} else if (unlock_inp == UH_WLOCKED)
1557 		INP_WUNLOCK(inp);
1558 	else
1559 		INP_RUNLOCK(inp);
1560 	m_freem(m);
1561 	return (error);
1562 }
1563 
1564 static void
1565 udp_abort(struct socket *so)
1566 {
1567 	struct inpcb *inp;
1568 	struct inpcbinfo *pcbinfo;
1569 
1570 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1571 	inp = sotoinpcb(so);
1572 	KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1573 	INP_WLOCK(inp);
1574 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1575 		INP_HASH_WLOCK(pcbinfo);
1576 		in_pcbdisconnect(inp);
1577 		inp->inp_laddr.s_addr = INADDR_ANY;
1578 		INP_HASH_WUNLOCK(pcbinfo);
1579 		soisdisconnected(so);
1580 	}
1581 	INP_WUNLOCK(inp);
1582 }
1583 
1584 static int
1585 udp_attach(struct socket *so, int proto, struct thread *td)
1586 {
1587 	struct inpcb *inp;
1588 	struct inpcbinfo *pcbinfo;
1589 	int error;
1590 
1591 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1592 	inp = sotoinpcb(so);
1593 	KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1594 	error = soreserve(so, udp_sendspace, udp_recvspace);
1595 	if (error)
1596 		return (error);
1597 	INP_INFO_WLOCK(pcbinfo);
1598 	error = in_pcballoc(so, pcbinfo);
1599 	if (error) {
1600 		INP_INFO_WUNLOCK(pcbinfo);
1601 		return (error);
1602 	}
1603 
1604 	inp = sotoinpcb(so);
1605 	inp->inp_vflag |= INP_IPV4;
1606 	inp->inp_ip_ttl = V_ip_defttl;
1607 
1608 	error = udp_newudpcb(inp);
1609 	if (error) {
1610 		in_pcbdetach(inp);
1611 		in_pcbfree(inp);
1612 		INP_INFO_WUNLOCK(pcbinfo);
1613 		return (error);
1614 	}
1615 
1616 	INP_WUNLOCK(inp);
1617 	INP_INFO_WUNLOCK(pcbinfo);
1618 	return (0);
1619 }
1620 #endif /* INET */
1621 
1622 int
1623 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1624 {
1625 	struct inpcb *inp;
1626 	struct udpcb *up;
1627 
1628 	KASSERT(so->so_type == SOCK_DGRAM,
1629 	    ("udp_set_kernel_tunneling: !dgram"));
1630 	inp = sotoinpcb(so);
1631 	KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1632 	INP_WLOCK(inp);
1633 	up = intoudpcb(inp);
1634 	if ((up->u_tun_func != NULL) ||
1635 	    (up->u_icmp_func != NULL)) {
1636 		INP_WUNLOCK(inp);
1637 		return (EBUSY);
1638 	}
1639 	up->u_tun_func = f;
1640 	up->u_icmp_func = i;
1641 	up->u_tun_ctx = ctx;
1642 	INP_WUNLOCK(inp);
1643 	return (0);
1644 }
1645 
1646 #ifdef INET
1647 static int
1648 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1649 {
1650 	struct inpcb *inp;
1651 	struct inpcbinfo *pcbinfo;
1652 	int error;
1653 
1654 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1655 	inp = sotoinpcb(so);
1656 	KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1657 	INP_WLOCK(inp);
1658 	INP_HASH_WLOCK(pcbinfo);
1659 	error = in_pcbbind(inp, nam, td->td_ucred);
1660 	INP_HASH_WUNLOCK(pcbinfo);
1661 	INP_WUNLOCK(inp);
1662 	return (error);
1663 }
1664 
1665 static void
1666 udp_close(struct socket *so)
1667 {
1668 	struct inpcb *inp;
1669 	struct inpcbinfo *pcbinfo;
1670 
1671 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1672 	inp = sotoinpcb(so);
1673 	KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1674 	INP_WLOCK(inp);
1675 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1676 		INP_HASH_WLOCK(pcbinfo);
1677 		in_pcbdisconnect(inp);
1678 		inp->inp_laddr.s_addr = INADDR_ANY;
1679 		INP_HASH_WUNLOCK(pcbinfo);
1680 		soisdisconnected(so);
1681 	}
1682 	INP_WUNLOCK(inp);
1683 }
1684 
1685 static int
1686 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1687 {
1688 	struct inpcb *inp;
1689 	struct inpcbinfo *pcbinfo;
1690 	struct sockaddr_in *sin;
1691 	int error;
1692 
1693 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1694 	inp = sotoinpcb(so);
1695 	KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1696 	INP_WLOCK(inp);
1697 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1698 		INP_WUNLOCK(inp);
1699 		return (EISCONN);
1700 	}
1701 	sin = (struct sockaddr_in *)nam;
1702 	error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1703 	if (error != 0) {
1704 		INP_WUNLOCK(inp);
1705 		return (error);
1706 	}
1707 	INP_HASH_WLOCK(pcbinfo);
1708 	error = in_pcbconnect(inp, nam, td->td_ucred);
1709 	INP_HASH_WUNLOCK(pcbinfo);
1710 	if (error == 0)
1711 		soisconnected(so);
1712 	INP_WUNLOCK(inp);
1713 	return (error);
1714 }
1715 
1716 static void
1717 udp_detach(struct socket *so)
1718 {
1719 	struct inpcb *inp;
1720 	struct inpcbinfo *pcbinfo;
1721 	struct udpcb *up;
1722 
1723 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1724 	inp = sotoinpcb(so);
1725 	KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1726 	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1727 	    ("udp_detach: not disconnected"));
1728 	INP_INFO_WLOCK(pcbinfo);
1729 	INP_WLOCK(inp);
1730 	up = intoudpcb(inp);
1731 	KASSERT(up != NULL, ("%s: up == NULL", __func__));
1732 	inp->inp_ppcb = NULL;
1733 	in_pcbdetach(inp);
1734 	in_pcbfree(inp);
1735 	INP_INFO_WUNLOCK(pcbinfo);
1736 	udp_discardcb(up);
1737 }
1738 
1739 static int
1740 udp_disconnect(struct socket *so)
1741 {
1742 	struct inpcb *inp;
1743 	struct inpcbinfo *pcbinfo;
1744 
1745 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1746 	inp = sotoinpcb(so);
1747 	KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1748 	INP_WLOCK(inp);
1749 	if (inp->inp_faddr.s_addr == INADDR_ANY) {
1750 		INP_WUNLOCK(inp);
1751 		return (ENOTCONN);
1752 	}
1753 	INP_HASH_WLOCK(pcbinfo);
1754 	in_pcbdisconnect(inp);
1755 	inp->inp_laddr.s_addr = INADDR_ANY;
1756 	INP_HASH_WUNLOCK(pcbinfo);
1757 	SOCK_LOCK(so);
1758 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
1759 	SOCK_UNLOCK(so);
1760 	INP_WUNLOCK(inp);
1761 	return (0);
1762 }
1763 
1764 static int
1765 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1766     struct mbuf *control, struct thread *td)
1767 {
1768 	struct inpcb *inp;
1769 
1770 	inp = sotoinpcb(so);
1771 	KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1772 	return (udp_output(inp, m, addr, control, td));
1773 }
1774 #endif /* INET */
1775 
1776 int
1777 udp_shutdown(struct socket *so)
1778 {
1779 	struct inpcb *inp;
1780 
1781 	inp = sotoinpcb(so);
1782 	KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1783 	INP_WLOCK(inp);
1784 	socantsendmore(so);
1785 	INP_WUNLOCK(inp);
1786 	return (0);
1787 }
1788 
1789 #ifdef INET
1790 struct pr_usrreqs udp_usrreqs = {
1791 	.pru_abort =		udp_abort,
1792 	.pru_attach =		udp_attach,
1793 	.pru_bind =		udp_bind,
1794 	.pru_connect =		udp_connect,
1795 	.pru_control =		in_control,
1796 	.pru_detach =		udp_detach,
1797 	.pru_disconnect =	udp_disconnect,
1798 	.pru_peeraddr =		in_getpeeraddr,
1799 	.pru_send =		udp_send,
1800 	.pru_soreceive =	soreceive_dgram,
1801 	.pru_sosend =		sosend_dgram,
1802 	.pru_shutdown =		udp_shutdown,
1803 	.pru_sockaddr =		in_getsockaddr,
1804 	.pru_sosetlabel =	in_pcbsosetlabel,
1805 	.pru_close =		udp_close,
1806 };
1807 #endif /* INET */
1808