xref: /freebsd/sys/netinet/udp_usrreq.c (revision 718519f4efc71096422fc71dab90b2a3369871ff)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
5  *	The Regents of the University of California.
6  * Copyright (c) 2008 Robert N. M. Watson
7  * Copyright (c) 2010-2011 Juniper Networks, Inc.
8  * Copyright (c) 2014 Kevin Lo
9  * All rights reserved.
10  *
11  * Portions of this software were developed by Robert N. M. Watson under
12  * contract to Juniper Networks, Inc.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #include "opt_inet.h"
41 #include "opt_inet6.h"
42 #include "opt_ipsec.h"
43 #include "opt_route.h"
44 #include "opt_rss.h"
45 
46 #include <sys/param.h>
47 #include <sys/domain.h>
48 #include <sys/eventhandler.h>
49 #include <sys/jail.h>
50 #include <sys/kernel.h>
51 #include <sys/lock.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/priv.h>
55 #include <sys/proc.h>
56 #include <sys/protosw.h>
57 #include <sys/sdt.h>
58 #include <sys/signalvar.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/sx.h>
62 #include <sys/sysctl.h>
63 #include <sys/syslog.h>
64 #include <sys/systm.h>
65 
66 #include <vm/uma.h>
67 
68 #include <net/if.h>
69 #include <net/if_var.h>
70 #include <net/route.h>
71 #include <net/route/nhop.h>
72 #include <net/rss_config.h>
73 
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_fib.h>
77 #include <netinet/in_pcb.h>
78 #include <netinet/in_systm.h>
79 #include <netinet/in_var.h>
80 #include <netinet/ip.h>
81 #ifdef INET6
82 #include <netinet/ip6.h>
83 #endif
84 #include <netinet/ip_icmp.h>
85 #include <netinet/icmp_var.h>
86 #include <netinet/ip_var.h>
87 #include <netinet/ip_options.h>
88 #ifdef INET6
89 #include <netinet6/ip6_var.h>
90 #endif
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93 #include <netinet/udplite.h>
94 #include <netinet/in_rss.h>
95 
96 #include <netipsec/ipsec_support.h>
97 
98 #include <machine/in_cksum.h>
99 
100 #include <security/mac/mac_framework.h>
101 
102 /*
103  * UDP and UDP-Lite protocols implementation.
104  * Per RFC 768, August, 1980.
105  * Per RFC 3828, July, 2004.
106  */
107 
108 /*
109  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
110  * removes the only data integrity mechanism for packets and malformed
111  * packets that would otherwise be discarded due to bad checksums, and may
112  * cause problems (especially for NFS data blocks).
113  */
114 VNET_DEFINE(int, udp_cksum) = 1;
115 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
116     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
117 
118 VNET_DEFINE(int, udp_log_in_vain) = 0;
119 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
120     &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
121 
122 VNET_DEFINE(int, udp_blackhole) = 0;
123 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
124     &VNET_NAME(udp_blackhole), 0,
125     "Do not send port unreachables for refused connects");
126 VNET_DEFINE(bool, udp_blackhole_local) = false;
127 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
128     CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
129     "Enforce net.inet.udp.blackhole for locally originated packets");
130 
131 u_long	udp_sendspace = 9216;		/* really max datagram size */
132 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
133     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
134 
135 u_long	udp_recvspace = 40 * (1024 +
136 #ifdef INET6
137 				      sizeof(struct sockaddr_in6)
138 #else
139 				      sizeof(struct sockaddr_in)
140 #endif
141 				      );	/* 40 1K datagrams */
142 
143 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
144     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
145 
146 VNET_DEFINE(struct inpcbinfo, udbinfo);
147 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
148 
149 #ifndef UDBHASHSIZE
150 #define	UDBHASHSIZE	128
151 #endif
152 
153 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);		/* from udp_var.h */
154 VNET_PCPUSTAT_SYSINIT(udpstat);
155 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
156     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
157 
158 #ifdef VIMAGE
159 VNET_PCPUSTAT_SYSUNINIT(udpstat);
160 #endif /* VIMAGE */
161 #ifdef INET
162 static void	udp_detach(struct socket *so);
163 #endif
164 
165 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
166 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
167     "udplite", "udplitehash");
168 
169 static void
170 udp_vnet_init(void *arg __unused)
171 {
172 
173 	/*
174 	 * For now default to 2-tuple UDP hashing - until the fragment
175 	 * reassembly code can also update the flowid.
176 	 *
177 	 * Once we can calculate the flowid that way and re-establish
178 	 * a 4-tuple, flip this to 4-tuple.
179 	 */
180 	in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
181 	/* Additional pcbinfo for UDP-Lite */
182 	in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
183 	    UDBHASHSIZE);
184 }
185 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
186     udp_vnet_init, NULL);
187 
188 /*
189  * Kernel module interface for updating udpstat.  The argument is an index
190  * into udpstat treated as an array of u_long.  While this encodes the
191  * general layout of udpstat into the caller, it doesn't encode its location,
192  * so that future changes to add, for example, per-CPU stats support won't
193  * cause binary compatibility problems for kernel modules.
194  */
195 void
196 kmod_udpstat_inc(int statnum)
197 {
198 
199 	counter_u64_add(VNET(udpstat)[statnum], 1);
200 }
201 
202 #ifdef VIMAGE
203 static void
204 udp_destroy(void *unused __unused)
205 {
206 
207 	in_pcbinfo_destroy(&V_udbinfo);
208 	in_pcbinfo_destroy(&V_ulitecbinfo);
209 }
210 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
211 #endif
212 
213 #ifdef INET
214 /*
215  * Subroutine of udp_input(), which appends the provided mbuf chain to the
216  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
217  * contains the source address.  If the socket ends up being an IPv6 socket,
218  * udp_append() will convert to a sockaddr_in6 before passing the address
219  * into the socket code.
220  *
221  * In the normal case udp_append() will return 0, indicating that you
222  * must unlock the inp. However if a tunneling protocol is in place we increment
223  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
224  * then decrement the reference count. If the inp_rele returns 1, indicating the
225  * inp is gone, we return that to the caller to tell them *not* to unlock
226  * the inp. In the case of multi-cast this will cause the distribution
227  * to stop (though most tunneling protocols known currently do *not* use
228  * multicast).
229  */
230 static int
231 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
232     struct sockaddr_in *udp_in)
233 {
234 	struct sockaddr *append_sa;
235 	struct socket *so;
236 	struct mbuf *tmpopts, *opts = NULL;
237 #ifdef INET6
238 	struct sockaddr_in6 udp_in6;
239 #endif
240 	struct udpcb *up;
241 	bool filtered;
242 
243 	INP_LOCK_ASSERT(inp);
244 
245 	/*
246 	 * Engage the tunneling protocol.
247 	 */
248 	up = intoudpcb(inp);
249 	if (up->u_tun_func != NULL) {
250 		in_pcbref(inp);
251 		INP_RUNLOCK(inp);
252 		filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
253 		    up->u_tun_ctx);
254 		INP_RLOCK(inp);
255 		if (filtered)
256 			return (in_pcbrele_rlocked(inp));
257 	}
258 
259 	off += sizeof(struct udphdr);
260 
261 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
262 	/* Check AH/ESP integrity. */
263 	if (IPSEC_ENABLED(ipv4) &&
264 	    IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
265 		m_freem(n);
266 		return (0);
267 	}
268 	if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
269 		if (IPSEC_ENABLED(ipv4) &&
270 		    UDPENCAP_INPUT(ipv4, n, off, AF_INET) != 0)
271 			return (0);	/* Consumed. */
272 	}
273 #endif /* IPSEC */
274 #ifdef MAC
275 	if (mac_inpcb_check_deliver(inp, n) != 0) {
276 		m_freem(n);
277 		return (0);
278 	}
279 #endif /* MAC */
280 	if (inp->inp_flags & INP_CONTROLOPTS ||
281 	    inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
282 #ifdef INET6
283 		if (inp->inp_vflag & INP_IPV6)
284 			(void)ip6_savecontrol_v4(inp, n, &opts, NULL);
285 		else
286 #endif /* INET6 */
287 			ip_savecontrol(inp, &opts, ip, n);
288 	}
289 	if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
290 		tmpopts = sbcreatecontrol(&udp_in[1],
291 		    sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
292 		    M_NOWAIT);
293 		if (tmpopts) {
294 			if (opts) {
295 				tmpopts->m_next = opts;
296 				opts = tmpopts;
297 			} else
298 				opts = tmpopts;
299 		}
300 	}
301 #ifdef INET6
302 	if (inp->inp_vflag & INP_IPV6) {
303 		bzero(&udp_in6, sizeof(udp_in6));
304 		udp_in6.sin6_len = sizeof(udp_in6);
305 		udp_in6.sin6_family = AF_INET6;
306 		in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
307 		append_sa = (struct sockaddr *)&udp_in6;
308 	} else
309 #endif /* INET6 */
310 		append_sa = (struct sockaddr *)&udp_in[0];
311 	m_adj(n, off);
312 
313 	so = inp->inp_socket;
314 	SOCKBUF_LOCK(&so->so_rcv);
315 	if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
316 		soroverflow_locked(so);
317 		m_freem(n);
318 		if (opts)
319 			m_freem(opts);
320 		UDPSTAT_INC(udps_fullsock);
321 	} else
322 		sorwakeup_locked(so);
323 	return (0);
324 }
325 
326 static bool
327 udp_multi_match(const struct inpcb *inp, void *v)
328 {
329 	struct ip *ip = v;
330 	struct udphdr *uh = (struct udphdr *)(ip + 1);
331 
332 	if (inp->inp_lport != uh->uh_dport)
333 		return (false);
334 #ifdef INET6
335 	if ((inp->inp_vflag & INP_IPV4) == 0)
336 		return (false);
337 #endif
338 	if (inp->inp_laddr.s_addr != INADDR_ANY &&
339 	    inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
340 		return (false);
341 	if (inp->inp_faddr.s_addr != INADDR_ANY &&
342 	    inp->inp_faddr.s_addr != ip->ip_src.s_addr)
343 		return (false);
344 	if (inp->inp_fport != 0 &&
345 	    inp->inp_fport != uh->uh_sport)
346 		return (false);
347 
348 	return (true);
349 }
350 
351 static int
352 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
353 {
354 	struct ip *ip = mtod(m, struct ip *);
355 	struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
356 	    INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
357 #ifdef KDTRACE_HOOKS
358 	struct udphdr *uh = (struct udphdr *)(ip + 1);
359 #endif
360 	struct inpcb *inp;
361 	struct mbuf *n;
362 	int appends = 0;
363 
364 	MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
365 
366 	while ((inp = inp_next(&inpi)) != NULL) {
367 		/*
368 		 * XXXRW: Because we weren't holding either the inpcb
369 		 * or the hash lock when we checked for a match
370 		 * before, we should probably recheck now that the
371 		 * inpcb lock is held.
372 		 */
373 		/*
374 		 * Handle socket delivery policy for any-source
375 		 * and source-specific multicast. [RFC3678]
376 		 */
377 		if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
378 			struct ip_moptions	*imo;
379 			struct sockaddr_in	 group;
380 			int			 blocked;
381 
382 			imo = inp->inp_moptions;
383 			if (imo == NULL)
384 				continue;
385 			bzero(&group, sizeof(struct sockaddr_in));
386 			group.sin_len = sizeof(struct sockaddr_in);
387 			group.sin_family = AF_INET;
388 			group.sin_addr = ip->ip_dst;
389 
390 			blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
391 				(struct sockaddr *)&group,
392 				(struct sockaddr *)&udp_in[0]);
393 			if (blocked != MCAST_PASS) {
394 				if (blocked == MCAST_NOTGMEMBER)
395 					IPSTAT_INC(ips_notmember);
396 				if (blocked == MCAST_NOTSMEMBER ||
397 				    blocked == MCAST_MUTED)
398 					UDPSTAT_INC(udps_filtermcast);
399 				continue;
400 			}
401 		}
402 		if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
403 			if (proto == IPPROTO_UDPLITE)
404 				UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
405 			else
406 				UDP_PROBE(receive, NULL, inp, ip, inp, uh);
407 			if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
408 				break;
409 			} else
410 				appends++;
411 		}
412 		/*
413 		 * Don't look for additional matches if this one does
414 		 * not have either the SO_REUSEPORT or SO_REUSEADDR
415 		 * socket options set.  This heuristic avoids
416 		 * searching through all pcbs in the common case of a
417 		 * non-shared port.  It assumes that an application
418 		 * will never clear these options after setting them.
419 		 */
420 		if ((inp->inp_socket->so_options &
421 		    (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
422 			INP_RUNLOCK(inp);
423 			break;
424 		}
425 	}
426 
427 	if (appends == 0) {
428 		/*
429 		 * No matching pcb found; discard datagram.  (No need
430 		 * to send an ICMP Port Unreachable for a broadcast
431 		 * or multicast datgram.)
432 		 */
433 		UDPSTAT_INC(udps_noport);
434 		if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
435 			UDPSTAT_INC(udps_noportmcast);
436 		else
437 			UDPSTAT_INC(udps_noportbcast);
438 	}
439 	m_freem(m);
440 
441 	return (IPPROTO_DONE);
442 }
443 
444 static int
445 udp_input(struct mbuf **mp, int *offp, int proto)
446 {
447 	struct ip *ip;
448 	struct udphdr *uh;
449 	struct ifnet *ifp;
450 	struct inpcb *inp;
451 	uint16_t len, ip_len;
452 	struct inpcbinfo *pcbinfo;
453 	struct sockaddr_in udp_in[2];
454 	struct mbuf *m;
455 	struct m_tag *fwd_tag;
456 	int cscov_partial, iphlen;
457 
458 	m = *mp;
459 	iphlen = *offp;
460 	ifp = m->m_pkthdr.rcvif;
461 	*mp = NULL;
462 	UDPSTAT_INC(udps_ipackets);
463 
464 	/*
465 	 * Strip IP options, if any; should skip this, make available to
466 	 * user, and use on returned packets, but we don't yet have a way to
467 	 * check the checksum with options still present.
468 	 */
469 	if (iphlen > sizeof (struct ip)) {
470 		ip_stripoptions(m);
471 		iphlen = sizeof(struct ip);
472 	}
473 
474 	/*
475 	 * Get IP and UDP header together in first mbuf.
476 	 */
477 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
478 		if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
479 			UDPSTAT_INC(udps_hdrops);
480 			return (IPPROTO_DONE);
481 		}
482 	}
483 	ip = mtod(m, struct ip *);
484 	uh = (struct udphdr *)((caddr_t)ip + iphlen);
485 	cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
486 
487 	/*
488 	 * Destination port of 0 is illegal, based on RFC768.
489 	 */
490 	if (uh->uh_dport == 0)
491 		goto badunlocked;
492 
493 	/*
494 	 * Construct sockaddr format source address.  Stuff source address
495 	 * and datagram in user buffer.
496 	 */
497 	bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
498 	udp_in[0].sin_len = sizeof(struct sockaddr_in);
499 	udp_in[0].sin_family = AF_INET;
500 	udp_in[0].sin_port = uh->uh_sport;
501 	udp_in[0].sin_addr = ip->ip_src;
502 	udp_in[1].sin_len = sizeof(struct sockaddr_in);
503 	udp_in[1].sin_family = AF_INET;
504 	udp_in[1].sin_port = uh->uh_dport;
505 	udp_in[1].sin_addr = ip->ip_dst;
506 
507 	/*
508 	 * Make mbuf data length reflect UDP length.  If not enough data to
509 	 * reflect UDP length, drop.
510 	 */
511 	len = ntohs((u_short)uh->uh_ulen);
512 	ip_len = ntohs(ip->ip_len) - iphlen;
513 	if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
514 		/* Zero means checksum over the complete packet. */
515 		if (len == 0)
516 			len = ip_len;
517 		cscov_partial = 0;
518 	}
519 	if (ip_len != len) {
520 		if (len > ip_len || len < sizeof(struct udphdr)) {
521 			UDPSTAT_INC(udps_badlen);
522 			goto badunlocked;
523 		}
524 		if (proto == IPPROTO_UDP)
525 			m_adj(m, len - ip_len);
526 	}
527 
528 	/*
529 	 * Checksum extended UDP header and data.
530 	 */
531 	if (uh->uh_sum) {
532 		u_short uh_sum;
533 
534 		if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
535 		    !cscov_partial) {
536 			if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
537 				uh_sum = m->m_pkthdr.csum_data;
538 			else
539 				uh_sum = in_pseudo(ip->ip_src.s_addr,
540 				    ip->ip_dst.s_addr, htonl((u_short)len +
541 				    m->m_pkthdr.csum_data + proto));
542 			uh_sum ^= 0xffff;
543 		} else {
544 			char b[offsetof(struct ipovly, ih_src)];
545 			struct ipovly *ipov = (struct ipovly *)ip;
546 
547 			bcopy(ipov, b, sizeof(b));
548 			bzero(ipov, sizeof(ipov->ih_x1));
549 			ipov->ih_len = (proto == IPPROTO_UDP) ?
550 			    uh->uh_ulen : htons(ip_len);
551 			uh_sum = in_cksum(m, len + sizeof (struct ip));
552 			bcopy(b, ipov, sizeof(b));
553 		}
554 		if (uh_sum) {
555 			UDPSTAT_INC(udps_badsum);
556 			m_freem(m);
557 			return (IPPROTO_DONE);
558 		}
559 	} else {
560 		if (proto == IPPROTO_UDP) {
561 			UDPSTAT_INC(udps_nosum);
562 		} else {
563 			/* UDPLite requires a checksum */
564 			/* XXX: What is the right UDPLite MIB counter here? */
565 			m_freem(m);
566 			return (IPPROTO_DONE);
567 		}
568 	}
569 
570 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
571 	    in_broadcast(ip->ip_dst, ifp))
572 		return (udp_multi_input(m, proto, udp_in));
573 
574 	pcbinfo = udp_get_inpcbinfo(proto);
575 
576 	/*
577 	 * Locate pcb for datagram.
578 	 *
579 	 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
580 	 */
581 	if ((m->m_flags & M_IP_NEXTHOP) &&
582 	    (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
583 		struct sockaddr_in *next_hop;
584 
585 		next_hop = (struct sockaddr_in *)(fwd_tag + 1);
586 
587 		/*
588 		 * Transparently forwarded. Pretend to be the destination.
589 		 * Already got one like this?
590 		 */
591 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
592 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
593 		if (!inp) {
594 			/*
595 			 * It's new.  Try to find the ambushing socket.
596 			 * Because we've rewritten the destination address,
597 			 * any hardware-generated hash is ignored.
598 			 */
599 			inp = in_pcblookup(pcbinfo, ip->ip_src,
600 			    uh->uh_sport, next_hop->sin_addr,
601 			    next_hop->sin_port ? htons(next_hop->sin_port) :
602 			    uh->uh_dport, INPLOOKUP_WILDCARD |
603 			    INPLOOKUP_RLOCKPCB, ifp);
604 		}
605 		/* Remove the tag from the packet. We don't need it anymore. */
606 		m_tag_delete(m, fwd_tag);
607 		m->m_flags &= ~M_IP_NEXTHOP;
608 	} else
609 		inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
610 		    ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
611 		    INPLOOKUP_RLOCKPCB, ifp, m);
612 	if (inp == NULL) {
613 		if (V_udp_log_in_vain) {
614 			char src[INET_ADDRSTRLEN];
615 			char dst[INET_ADDRSTRLEN];
616 
617 			log(LOG_INFO,
618 			    "Connection attempt to UDP %s:%d from %s:%d\n",
619 			    inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
620 			    inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
621 		}
622 		if (proto == IPPROTO_UDPLITE)
623 			UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
624 		else
625 			UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
626 		UDPSTAT_INC(udps_noport);
627 		if (m->m_flags & (M_BCAST | M_MCAST)) {
628 			UDPSTAT_INC(udps_noportbcast);
629 			goto badunlocked;
630 		}
631 		if (V_udp_blackhole && (V_udp_blackhole_local ||
632 		    !in_localip(ip->ip_src)))
633 			goto badunlocked;
634 		if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
635 			goto badunlocked;
636 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
637 		return (IPPROTO_DONE);
638 	}
639 
640 	/*
641 	 * Check the minimum TTL for socket.
642 	 */
643 	INP_RLOCK_ASSERT(inp);
644 	if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
645 		if (proto == IPPROTO_UDPLITE)
646 			UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
647 		else
648 			UDP_PROBE(receive, NULL, inp, ip, inp, uh);
649 		INP_RUNLOCK(inp);
650 		m_freem(m);
651 		return (IPPROTO_DONE);
652 	}
653 	if (cscov_partial) {
654 		struct udpcb *up;
655 
656 		up = intoudpcb(inp);
657 		if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
658 			INP_RUNLOCK(inp);
659 			m_freem(m);
660 			return (IPPROTO_DONE);
661 		}
662 	}
663 
664 	if (proto == IPPROTO_UDPLITE)
665 		UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
666 	else
667 		UDP_PROBE(receive, NULL, inp, ip, inp, uh);
668 	if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
669 		INP_RUNLOCK(inp);
670 	return (IPPROTO_DONE);
671 
672 badunlocked:
673 	m_freem(m);
674 	return (IPPROTO_DONE);
675 }
676 #endif /* INET */
677 
678 /*
679  * Notify a udp user of an asynchronous error; just wake up so that they can
680  * collect error status.
681  */
682 struct inpcb *
683 udp_notify(struct inpcb *inp, int errno)
684 {
685 
686 	INP_WLOCK_ASSERT(inp);
687 	if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
688 	     errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
689 		NH_FREE(inp->inp_route.ro_nh);
690 		inp->inp_route.ro_nh = (struct nhop_object *)NULL;
691 	}
692 
693 	inp->inp_socket->so_error = errno;
694 	sorwakeup(inp->inp_socket);
695 	sowwakeup(inp->inp_socket);
696 	return (inp);
697 }
698 
699 #ifdef INET
700 static void
701 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
702 {
703 	struct ip *ip = &icmp->icmp_ip;
704 	struct udphdr *uh;
705 	struct inpcb *inp;
706 
707 	if (icmp_errmap(icmp) == 0)
708 		return;
709 
710 	uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
711 	inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
712 	    uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
713 	if (inp != NULL) {
714 		INP_WLOCK_ASSERT(inp);
715 		if (inp->inp_socket != NULL)
716 			udp_notify(inp, icmp_errmap(icmp));
717 		INP_WUNLOCK(inp);
718 	} else {
719 		inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
720 		    ip->ip_src, uh->uh_sport,
721 		    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
722 		if (inp != NULL) {
723 			struct udpcb *up;
724 			udp_tun_icmp_t *func;
725 
726 			up = intoudpcb(inp);
727 			func = up->u_icmp_func;
728 			INP_RUNLOCK(inp);
729 			if (func != NULL)
730 				func(icmp);
731 		}
732 	}
733 }
734 
735 static void
736 udp_ctlinput(struct icmp *icmp)
737 {
738 
739 	return (udp_common_ctlinput(icmp, &V_udbinfo));
740 }
741 
742 static void
743 udplite_ctlinput(struct icmp *icmp)
744 {
745 
746 	return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
747 }
748 #endif /* INET */
749 
750 static int
751 udp_pcblist(SYSCTL_HANDLER_ARGS)
752 {
753 	struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
754 	    INPLOOKUP_RLOCKPCB);
755 	struct xinpgen xig;
756 	struct inpcb *inp;
757 	int error;
758 
759 	if (req->newptr != 0)
760 		return (EPERM);
761 
762 	if (req->oldptr == 0) {
763 		int n;
764 
765 		n = V_udbinfo.ipi_count;
766 		n += imax(n / 8, 10);
767 		req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
768 		return (0);
769 	}
770 
771 	if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
772 		return (error);
773 
774 	bzero(&xig, sizeof(xig));
775 	xig.xig_len = sizeof xig;
776 	xig.xig_count = V_udbinfo.ipi_count;
777 	xig.xig_gen = V_udbinfo.ipi_gencnt;
778 	xig.xig_sogen = so_gencnt;
779 	error = SYSCTL_OUT(req, &xig, sizeof xig);
780 	if (error)
781 		return (error);
782 
783 	while ((inp = inp_next(&inpi)) != NULL) {
784 		if (inp->inp_gencnt <= xig.xig_gen &&
785 		    cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
786 			struct xinpcb xi;
787 
788 			in_pcbtoxinpcb(inp, &xi);
789 			error = SYSCTL_OUT(req, &xi, sizeof xi);
790 			if (error) {
791 				INP_RUNLOCK(inp);
792 				break;
793 			}
794 		}
795 	}
796 
797 	if (!error) {
798 		/*
799 		 * Give the user an updated idea of our state.  If the
800 		 * generation differs from what we told her before, she knows
801 		 * that something happened while we were processing this
802 		 * request, and it might be necessary to retry.
803 		 */
804 		xig.xig_gen = V_udbinfo.ipi_gencnt;
805 		xig.xig_sogen = so_gencnt;
806 		xig.xig_count = V_udbinfo.ipi_count;
807 		error = SYSCTL_OUT(req, &xig, sizeof xig);
808 	}
809 
810 	return (error);
811 }
812 
813 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
814     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
815     udp_pcblist, "S,xinpcb",
816     "List of active UDP sockets");
817 
818 #ifdef INET
819 static int
820 udp_getcred(SYSCTL_HANDLER_ARGS)
821 {
822 	struct xucred xuc;
823 	struct sockaddr_in addrs[2];
824 	struct epoch_tracker et;
825 	struct inpcb *inp;
826 	int error;
827 
828 	error = priv_check(req->td, PRIV_NETINET_GETCRED);
829 	if (error)
830 		return (error);
831 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
832 	if (error)
833 		return (error);
834 	NET_EPOCH_ENTER(et);
835 	inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
836 	    addrs[0].sin_addr, addrs[0].sin_port,
837 	    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
838 	NET_EPOCH_EXIT(et);
839 	if (inp != NULL) {
840 		INP_RLOCK_ASSERT(inp);
841 		if (inp->inp_socket == NULL)
842 			error = ENOENT;
843 		if (error == 0)
844 			error = cr_canseeinpcb(req->td->td_ucred, inp);
845 		if (error == 0)
846 			cru2x(inp->inp_cred, &xuc);
847 		INP_RUNLOCK(inp);
848 	} else
849 		error = ENOENT;
850 	if (error == 0)
851 		error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
852 	return (error);
853 }
854 
855 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
856     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
857     0, 0, udp_getcred, "S,xucred",
858     "Get the xucred of a UDP connection");
859 #endif /* INET */
860 
861 int
862 udp_ctloutput(struct socket *so, struct sockopt *sopt)
863 {
864 	struct inpcb *inp;
865 	struct udpcb *up;
866 	int isudplite, error, optval;
867 
868 	error = 0;
869 	isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
870 	inp = sotoinpcb(so);
871 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
872 	INP_WLOCK(inp);
873 	if (sopt->sopt_level != so->so_proto->pr_protocol) {
874 #ifdef INET6
875 		if (INP_CHECK_SOCKAF(so, AF_INET6)) {
876 			INP_WUNLOCK(inp);
877 			error = ip6_ctloutput(so, sopt);
878 		}
879 #endif
880 #if defined(INET) && defined(INET6)
881 		else
882 #endif
883 #ifdef INET
884 		{
885 			INP_WUNLOCK(inp);
886 			error = ip_ctloutput(so, sopt);
887 		}
888 #endif
889 		return (error);
890 	}
891 
892 	switch (sopt->sopt_dir) {
893 	case SOPT_SET:
894 		switch (sopt->sopt_name) {
895 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
896 #if defined(INET) || defined(INET6)
897 		case UDP_ENCAP:
898 #ifdef INET
899 			if (INP_SOCKAF(so) == AF_INET) {
900 				if (!IPSEC_ENABLED(ipv4)) {
901 					INP_WUNLOCK(inp);
902 					return (ENOPROTOOPT);
903 				}
904 				error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
905 				break;
906 			}
907 #endif /* INET */
908 #ifdef INET6
909 			if (INP_SOCKAF(so) == AF_INET6) {
910 				if (!IPSEC_ENABLED(ipv6)) {
911 					INP_WUNLOCK(inp);
912 					return (ENOPROTOOPT);
913 				}
914 				error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
915 				break;
916 			}
917 #endif /* INET6 */
918 			INP_WUNLOCK(inp);
919 			return (EINVAL);
920 #endif /* INET || INET6 */
921 
922 #endif /* IPSEC */
923 		case UDPLITE_SEND_CSCOV:
924 		case UDPLITE_RECV_CSCOV:
925 			if (!isudplite) {
926 				INP_WUNLOCK(inp);
927 				error = ENOPROTOOPT;
928 				break;
929 			}
930 			INP_WUNLOCK(inp);
931 			error = sooptcopyin(sopt, &optval, sizeof(optval),
932 			    sizeof(optval));
933 			if (error != 0)
934 				break;
935 			inp = sotoinpcb(so);
936 			KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
937 			INP_WLOCK(inp);
938 			up = intoudpcb(inp);
939 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
940 			if ((optval != 0 && optval < 8) || (optval > 65535)) {
941 				INP_WUNLOCK(inp);
942 				error = EINVAL;
943 				break;
944 			}
945 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
946 				up->u_txcslen = optval;
947 			else
948 				up->u_rxcslen = optval;
949 			INP_WUNLOCK(inp);
950 			break;
951 		default:
952 			INP_WUNLOCK(inp);
953 			error = ENOPROTOOPT;
954 			break;
955 		}
956 		break;
957 	case SOPT_GET:
958 		switch (sopt->sopt_name) {
959 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
960 #if defined(INET) || defined(INET6)
961 		case UDP_ENCAP:
962 #ifdef INET
963 			if (INP_SOCKAF(so) == AF_INET) {
964 				if (!IPSEC_ENABLED(ipv4)) {
965 					INP_WUNLOCK(inp);
966 					return (ENOPROTOOPT);
967 				}
968 				error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
969 				break;
970 			}
971 #endif /* INET */
972 #ifdef INET6
973 			if (INP_SOCKAF(so) == AF_INET6) {
974 				if (!IPSEC_ENABLED(ipv6)) {
975 					INP_WUNLOCK(inp);
976 					return (ENOPROTOOPT);
977 				}
978 				error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
979 				break;
980 			}
981 #endif /* INET6 */
982 			INP_WUNLOCK(inp);
983 			return (EINVAL);
984 #endif /* INET || INET6 */
985 
986 #endif /* IPSEC */
987 		case UDPLITE_SEND_CSCOV:
988 		case UDPLITE_RECV_CSCOV:
989 			if (!isudplite) {
990 				INP_WUNLOCK(inp);
991 				error = ENOPROTOOPT;
992 				break;
993 			}
994 			up = intoudpcb(inp);
995 			KASSERT(up != NULL, ("%s: up == NULL", __func__));
996 			if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
997 				optval = up->u_txcslen;
998 			else
999 				optval = up->u_rxcslen;
1000 			INP_WUNLOCK(inp);
1001 			error = sooptcopyout(sopt, &optval, sizeof(optval));
1002 			break;
1003 		default:
1004 			INP_WUNLOCK(inp);
1005 			error = ENOPROTOOPT;
1006 			break;
1007 		}
1008 		break;
1009 	}
1010 	return (error);
1011 }
1012 
1013 #ifdef INET
1014 #ifdef INET6
1015 /* The logic here is derived from ip6_setpktopt(). See comments there. */
1016 static int
1017 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
1018     struct inpcb *inp, int flags)
1019 {
1020 	struct ifnet *ifp;
1021 	struct in6_pktinfo *pktinfo;
1022 	struct in_addr ia;
1023 
1024 	if ((flags & PRUS_IPV6) == 0)
1025 		return (0);
1026 
1027 	if (cm->cmsg_level != IPPROTO_IPV6)
1028 		return (0);
1029 
1030 	if  (cm->cmsg_type != IPV6_2292PKTINFO &&
1031 	    cm->cmsg_type != IPV6_PKTINFO)
1032 		return (0);
1033 
1034 	if (cm->cmsg_len !=
1035 	    CMSG_LEN(sizeof(struct in6_pktinfo)))
1036 		return (EINVAL);
1037 
1038 	pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1039 	if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1040 	    !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1041 		return (EINVAL);
1042 
1043 	/* Validate the interface index if specified. */
1044 	if (pktinfo->ipi6_ifindex) {
1045 		struct epoch_tracker et;
1046 
1047 		NET_EPOCH_ENTER(et);
1048 		ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1049 		NET_EPOCH_EXIT(et);	/* XXXGL: unsafe ifp */
1050 		if (ifp == NULL)
1051 			return (ENXIO);
1052 	} else
1053 		ifp = NULL;
1054 	if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1055 		ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1056 		if (in_ifhasaddr(ifp, ia) == 0)
1057 			return (EADDRNOTAVAIL);
1058 	}
1059 
1060 	bzero(src, sizeof(*src));
1061 	src->sin_family = AF_INET;
1062 	src->sin_len = sizeof(*src);
1063 	src->sin_port = inp->inp_lport;
1064 	src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1065 
1066 	return (0);
1067 }
1068 #endif	/* INET6 */
1069 
1070 int
1071 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1072     struct mbuf *control, struct thread *td)
1073 {
1074 	struct inpcb *inp;
1075 	struct udpiphdr *ui;
1076 	int len, error = 0;
1077 	struct in_addr faddr, laddr;
1078 	struct cmsghdr *cm;
1079 	struct inpcbinfo *pcbinfo;
1080 	struct sockaddr_in *sin, src;
1081 	struct epoch_tracker et;
1082 	int cscov_partial = 0;
1083 	int ipflags = 0;
1084 	u_short fport, lport;
1085 	u_char tos, vflagsav;
1086 	uint8_t pr;
1087 	uint16_t cscov = 0;
1088 	uint32_t flowid = 0;
1089 	uint8_t flowtype = M_HASHTYPE_NONE;
1090 	bool use_cached_route;
1091 
1092 	inp = sotoinpcb(so);
1093 	KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1094 
1095 	if (addr != NULL) {
1096 		if (addr->sa_family != AF_INET)
1097 			error = EAFNOSUPPORT;
1098 		else if (addr->sa_len != sizeof(struct sockaddr_in))
1099 			error = EINVAL;
1100 		if (__predict_false(error != 0)) {
1101 			m_freem(control);
1102 			m_freem(m);
1103 			return (error);
1104 		}
1105 	}
1106 
1107 	len = m->m_pkthdr.len;
1108 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1109 		if (control)
1110 			m_freem(control);
1111 		m_freem(m);
1112 		return (EMSGSIZE);
1113 	}
1114 
1115 	src.sin_family = 0;
1116 	sin = (struct sockaddr_in *)addr;
1117 
1118 	/*
1119 	 * udp_send() may need to temporarily bind or connect the current
1120 	 * inpcb.  As such, we don't know up front whether we will need the
1121 	 * pcbinfo lock or not.  Do any work to decide what is needed up
1122 	 * front before acquiring any locks.
1123 	 *
1124 	 * We will need network epoch in either case, to safely lookup into
1125 	 * pcb hash.
1126 	 */
1127 	use_cached_route = sin == NULL || (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0);
1128 	if (use_cached_route || (flags & PRUS_IPV6) != 0)
1129 		INP_WLOCK(inp);
1130 	else
1131 		INP_RLOCK(inp);
1132 	NET_EPOCH_ENTER(et);
1133 	tos = inp->inp_ip_tos;
1134 	if (control != NULL) {
1135 		/*
1136 		 * XXX: Currently, we assume all the optional information is
1137 		 * stored in a single mbuf.
1138 		 */
1139 		if (control->m_next) {
1140 			m_freem(control);
1141 			error = EINVAL;
1142 			goto release;
1143 		}
1144 		for (; control->m_len > 0;
1145 		    control->m_data += CMSG_ALIGN(cm->cmsg_len),
1146 		    control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1147 			cm = mtod(control, struct cmsghdr *);
1148 			if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1149 			    || cm->cmsg_len > control->m_len) {
1150 				error = EINVAL;
1151 				break;
1152 			}
1153 #ifdef INET6
1154 			error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1155 			if (error != 0)
1156 				break;
1157 #endif
1158 			if (cm->cmsg_level != IPPROTO_IP)
1159 				continue;
1160 
1161 			switch (cm->cmsg_type) {
1162 			case IP_SENDSRCADDR:
1163 				if (cm->cmsg_len !=
1164 				    CMSG_LEN(sizeof(struct in_addr))) {
1165 					error = EINVAL;
1166 					break;
1167 				}
1168 				bzero(&src, sizeof(src));
1169 				src.sin_family = AF_INET;
1170 				src.sin_len = sizeof(src);
1171 				src.sin_port = inp->inp_lport;
1172 				src.sin_addr =
1173 				    *(struct in_addr *)CMSG_DATA(cm);
1174 				break;
1175 
1176 			case IP_TOS:
1177 				if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1178 					error = EINVAL;
1179 					break;
1180 				}
1181 				tos = *(u_char *)CMSG_DATA(cm);
1182 				break;
1183 
1184 			case IP_FLOWID:
1185 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1186 					error = EINVAL;
1187 					break;
1188 				}
1189 				flowid = *(uint32_t *) CMSG_DATA(cm);
1190 				break;
1191 
1192 			case IP_FLOWTYPE:
1193 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1194 					error = EINVAL;
1195 					break;
1196 				}
1197 				flowtype = *(uint32_t *) CMSG_DATA(cm);
1198 				break;
1199 
1200 #ifdef	RSS
1201 			case IP_RSSBUCKETID:
1202 				if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1203 					error = EINVAL;
1204 					break;
1205 				}
1206 				/* This is just a placeholder for now */
1207 				break;
1208 #endif	/* RSS */
1209 			default:
1210 				error = ENOPROTOOPT;
1211 				break;
1212 			}
1213 			if (error)
1214 				break;
1215 		}
1216 		m_freem(control);
1217 		control = NULL;
1218 	}
1219 	if (error)
1220 		goto release;
1221 
1222 	pr = inp->inp_socket->so_proto->pr_protocol;
1223 	pcbinfo = udp_get_inpcbinfo(pr);
1224 
1225 	/*
1226 	 * If the IP_SENDSRCADDR control message was specified, override the
1227 	 * source address for this datagram.  Its use is invalidated if the
1228 	 * address thus specified is incomplete or clobbers other inpcbs.
1229 	 */
1230 	laddr = inp->inp_laddr;
1231 	lport = inp->inp_lport;
1232 	if (src.sin_family == AF_INET) {
1233 		if ((lport == 0) ||
1234 		    (laddr.s_addr == INADDR_ANY &&
1235 		     src.sin_addr.s_addr == INADDR_ANY)) {
1236 			error = EINVAL;
1237 			goto release;
1238 		}
1239 		if ((flags & PRUS_IPV6) != 0) {
1240 			vflagsav = inp->inp_vflag;
1241 			inp->inp_vflag |= INP_IPV4;
1242 			inp->inp_vflag &= ~INP_IPV6;
1243 		}
1244 		INP_HASH_WLOCK(pcbinfo);
1245 		error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1246 		    td->td_ucred);
1247 		INP_HASH_WUNLOCK(pcbinfo);
1248 		if ((flags & PRUS_IPV6) != 0)
1249 			inp->inp_vflag = vflagsav;
1250 		if (error)
1251 			goto release;
1252 	}
1253 
1254 	/*
1255 	 * If a UDP socket has been connected, then a local address/port will
1256 	 * have been selected and bound.
1257 	 *
1258 	 * If a UDP socket has not been connected to, then an explicit
1259 	 * destination address must be used, in which case a local
1260 	 * address/port may not have been selected and bound.
1261 	 */
1262 	if (sin != NULL) {
1263 		INP_LOCK_ASSERT(inp);
1264 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
1265 			error = EISCONN;
1266 			goto release;
1267 		}
1268 
1269 		/*
1270 		 * Jail may rewrite the destination address, so let it do
1271 		 * that before we use it.
1272 		 */
1273 		error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1274 		if (error)
1275 			goto release;
1276 
1277 		/*
1278 		 * If a local address or port hasn't yet been selected, or if
1279 		 * the destination address needs to be rewritten due to using
1280 		 * a special INADDR_ constant, invoke in_pcbconnect_setup()
1281 		 * to do the heavy lifting.  Once a port is selected, we
1282 		 * commit the binding back to the socket; we also commit the
1283 		 * binding of the address if in jail.
1284 		 *
1285 		 * If we already have a valid binding and we're not
1286 		 * requesting a destination address rewrite, use a fast path.
1287 		 */
1288 		if (inp->inp_laddr.s_addr == INADDR_ANY ||
1289 		    inp->inp_lport == 0 ||
1290 		    sin->sin_addr.s_addr == INADDR_ANY ||
1291 		    sin->sin_addr.s_addr == INADDR_BROADCAST) {
1292 			if ((flags & PRUS_IPV6) != 0) {
1293 				vflagsav = inp->inp_vflag;
1294 				inp->inp_vflag |= INP_IPV4;
1295 				inp->inp_vflag &= ~INP_IPV6;
1296 			}
1297 			INP_HASH_WLOCK(pcbinfo);
1298 			error = in_pcbconnect_setup(inp, sin, &laddr.s_addr,
1299 			    &lport, &faddr.s_addr, &fport, td->td_ucred);
1300 			if ((flags & PRUS_IPV6) != 0)
1301 				inp->inp_vflag = vflagsav;
1302 			if (error) {
1303 				INP_HASH_WUNLOCK(pcbinfo);
1304 				goto release;
1305 			}
1306 
1307 			/*
1308 			 * XXXRW: Why not commit the port if the address is
1309 			 * !INADDR_ANY?
1310 			 */
1311 			/* Commit the local port if newly assigned. */
1312 			if (inp->inp_laddr.s_addr == INADDR_ANY &&
1313 			    inp->inp_lport == 0) {
1314 				INP_WLOCK_ASSERT(inp);
1315 				/*
1316 				 * Remember addr if jailed, to prevent
1317 				 * rebinding.
1318 				 */
1319 				if (prison_flag(td->td_ucred, PR_IP4))
1320 					inp->inp_laddr = laddr;
1321 				inp->inp_lport = lport;
1322 				error = in_pcbinshash(inp);
1323 				INP_HASH_WUNLOCK(pcbinfo);
1324 				if (error != 0) {
1325 					inp->inp_lport = 0;
1326 					error = EAGAIN;
1327 					goto release;
1328 				}
1329 				inp->inp_flags |= INP_ANONPORT;
1330 			} else
1331 				INP_HASH_WUNLOCK(pcbinfo);
1332 		} else {
1333 			faddr = sin->sin_addr;
1334 			fport = sin->sin_port;
1335 		}
1336 	} else {
1337 		INP_LOCK_ASSERT(inp);
1338 		faddr = inp->inp_faddr;
1339 		fport = inp->inp_fport;
1340 		if (faddr.s_addr == INADDR_ANY) {
1341 			error = ENOTCONN;
1342 			goto release;
1343 		}
1344 	}
1345 
1346 	/*
1347 	 * Calculate data length and get a mbuf for UDP, IP, and possible
1348 	 * link-layer headers.  Immediate slide the data pointer back forward
1349 	 * since we won't use that space at this layer.
1350 	 */
1351 	M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1352 	if (m == NULL) {
1353 		error = ENOBUFS;
1354 		goto release;
1355 	}
1356 	m->m_data += max_linkhdr;
1357 	m->m_len -= max_linkhdr;
1358 	m->m_pkthdr.len -= max_linkhdr;
1359 
1360 	/*
1361 	 * Fill in mbuf with extended UDP header and addresses and length put
1362 	 * into network format.
1363 	 */
1364 	ui = mtod(m, struct udpiphdr *);
1365 	/*
1366 	 * Filling only those fields of udpiphdr that participate in the
1367 	 * checksum calculation. The rest must be zeroed and will be filled
1368 	 * later.
1369 	 */
1370 	bzero(ui->ui_x1, sizeof(ui->ui_x1));
1371 	ui->ui_pr = pr;
1372 	ui->ui_src = laddr;
1373 	ui->ui_dst = faddr;
1374 	ui->ui_sport = lport;
1375 	ui->ui_dport = fport;
1376 	ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1377 	if (pr == IPPROTO_UDPLITE) {
1378 		struct udpcb *up;
1379 		uint16_t plen;
1380 
1381 		up = intoudpcb(inp);
1382 		cscov = up->u_txcslen;
1383 		plen = (u_short)len + sizeof(struct udphdr);
1384 		if (cscov >= plen)
1385 			cscov = 0;
1386 		ui->ui_len = htons(plen);
1387 		ui->ui_ulen = htons(cscov);
1388 		/*
1389 		 * For UDP-Lite, checksum coverage length of zero means
1390 		 * the entire UDPLite packet is covered by the checksum.
1391 		 */
1392 		cscov_partial = (cscov == 0) ? 0 : 1;
1393 	}
1394 
1395 	if (inp->inp_socket->so_options & SO_DONTROUTE)
1396 		ipflags |= IP_ROUTETOIF;
1397 	if (inp->inp_socket->so_options & SO_BROADCAST)
1398 		ipflags |= IP_ALLOWBROADCAST;
1399 	if (inp->inp_flags & INP_ONESBCAST)
1400 		ipflags |= IP_SENDONES;
1401 
1402 #ifdef MAC
1403 	mac_inpcb_create_mbuf(inp, m);
1404 #endif
1405 
1406 	/*
1407 	 * Set up checksum and output datagram.
1408 	 */
1409 	ui->ui_sum = 0;
1410 	if (pr == IPPROTO_UDPLITE) {
1411 		if (inp->inp_flags & INP_ONESBCAST)
1412 			faddr.s_addr = INADDR_BROADCAST;
1413 		if (cscov_partial) {
1414 			if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1415 				ui->ui_sum = 0xffff;
1416 		} else {
1417 			if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1418 				ui->ui_sum = 0xffff;
1419 		}
1420 	} else if (V_udp_cksum) {
1421 		if (inp->inp_flags & INP_ONESBCAST)
1422 			faddr.s_addr = INADDR_BROADCAST;
1423 		ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1424 		    htons((u_short)len + sizeof(struct udphdr) + pr));
1425 		m->m_pkthdr.csum_flags = CSUM_UDP;
1426 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1427 	}
1428 	/*
1429 	 * After finishing the checksum computation, fill the remaining fields
1430 	 * of udpiphdr.
1431 	 */
1432 	((struct ip *)ui)->ip_v = IPVERSION;
1433 	((struct ip *)ui)->ip_tos = tos;
1434 	((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1435 	if (inp->inp_flags & INP_DONTFRAG)
1436 		((struct ip *)ui)->ip_off |= htons(IP_DF);
1437 	((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;
1438 	UDPSTAT_INC(udps_opackets);
1439 
1440 	/*
1441 	 * Setup flowid / RSS information for outbound socket.
1442 	 *
1443 	 * Once the UDP code decides to set a flowid some other way,
1444 	 * this allows the flowid to be overridden by userland.
1445 	 */
1446 	if (flowtype != M_HASHTYPE_NONE) {
1447 		m->m_pkthdr.flowid = flowid;
1448 		M_HASHTYPE_SET(m, flowtype);
1449 	}
1450 #if defined(ROUTE_MPATH) || defined(RSS)
1451 	else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1452 		uint32_t hash_val, hash_type;
1453 
1454 		hash_val = fib4_calc_packet_hash(laddr, faddr,
1455 		    lport, fport, pr, &hash_type);
1456 		m->m_pkthdr.flowid = hash_val;
1457 		M_HASHTYPE_SET(m, hash_type);
1458 	}
1459 
1460 	/*
1461 	 * Don't override with the inp cached flowid value.
1462 	 *
1463 	 * Depending upon the kind of send being done, the inp
1464 	 * flowid/flowtype values may actually not be appropriate
1465 	 * for this particular socket send.
1466 	 *
1467 	 * We should either leave the flowid at zero (which is what is
1468 	 * currently done) or set it to some software generated
1469 	 * hash value based on the packet contents.
1470 	 */
1471 	ipflags |= IP_NODEFAULTFLOWID;
1472 #endif	/* RSS */
1473 
1474 	if (pr == IPPROTO_UDPLITE)
1475 		UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1476 	else
1477 		UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1478 	error = ip_output(m, inp->inp_options,
1479 	    use_cached_route ? &inp->inp_route : NULL, ipflags,
1480 	    inp->inp_moptions, inp);
1481 	INP_UNLOCK(inp);
1482 	NET_EPOCH_EXIT(et);
1483 	return (error);
1484 
1485 release:
1486 	INP_UNLOCK(inp);
1487 	NET_EPOCH_EXIT(et);
1488 	m_freem(m);
1489 	return (error);
1490 }
1491 
1492 void
1493 udp_abort(struct socket *so)
1494 {
1495 	struct inpcb *inp;
1496 	struct inpcbinfo *pcbinfo;
1497 
1498 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1499 	inp = sotoinpcb(so);
1500 	KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1501 	INP_WLOCK(inp);
1502 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1503 		INP_HASH_WLOCK(pcbinfo);
1504 		in_pcbdisconnect(inp);
1505 		INP_HASH_WUNLOCK(pcbinfo);
1506 		soisdisconnected(so);
1507 	}
1508 	INP_WUNLOCK(inp);
1509 }
1510 
1511 static int
1512 udp_attach(struct socket *so, int proto, struct thread *td)
1513 {
1514 	static uint32_t udp_flowid;
1515 	struct inpcbinfo *pcbinfo;
1516 	struct inpcb *inp;
1517 	struct udpcb *up;
1518 	int error;
1519 
1520 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1521 	inp = sotoinpcb(so);
1522 	KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1523 	error = soreserve(so, udp_sendspace, udp_recvspace);
1524 	if (error)
1525 		return (error);
1526 	error = in_pcballoc(so, pcbinfo);
1527 	if (error)
1528 		return (error);
1529 
1530 	inp = sotoinpcb(so);
1531 	inp->inp_ip_ttl = V_ip_defttl;
1532 	inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1533 	inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1534 	up = intoudpcb(inp);
1535 	bzero(&up->u_start_zero, u_zero_size);
1536 	INP_WUNLOCK(inp);
1537 
1538 	return (0);
1539 }
1540 #endif /* INET */
1541 
1542 int
1543 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1544 {
1545 	struct inpcb *inp;
1546 	struct udpcb *up;
1547 
1548 	KASSERT(so->so_type == SOCK_DGRAM,
1549 	    ("udp_set_kernel_tunneling: !dgram"));
1550 	inp = sotoinpcb(so);
1551 	KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1552 	INP_WLOCK(inp);
1553 	up = intoudpcb(inp);
1554 	if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1555 	    (up->u_icmp_func != NULL))) {
1556 		INP_WUNLOCK(inp);
1557 		return (EBUSY);
1558 	}
1559 	up->u_tun_func = f;
1560 	up->u_icmp_func = i;
1561 	up->u_tun_ctx = ctx;
1562 	INP_WUNLOCK(inp);
1563 	return (0);
1564 }
1565 
1566 #ifdef INET
1567 static int
1568 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1569 {
1570 	struct inpcb *inp;
1571 	struct inpcbinfo *pcbinfo;
1572 	struct sockaddr_in *sinp;
1573 	int error;
1574 
1575 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1576 	inp = sotoinpcb(so);
1577 	KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1578 
1579 	sinp = (struct sockaddr_in *)nam;
1580 	if (nam->sa_family != AF_INET) {
1581 		/*
1582 		 * Preserve compatibility with old programs.
1583 		 */
1584 		if (nam->sa_family != AF_UNSPEC ||
1585 		    nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1586 		    sinp->sin_addr.s_addr != INADDR_ANY)
1587 			return (EAFNOSUPPORT);
1588 		nam->sa_family = AF_INET;
1589 	}
1590 	if (nam->sa_len != sizeof(struct sockaddr_in))
1591 		return (EINVAL);
1592 
1593 	INP_WLOCK(inp);
1594 	INP_HASH_WLOCK(pcbinfo);
1595 	error = in_pcbbind(inp, sinp, td->td_ucred);
1596 	INP_HASH_WUNLOCK(pcbinfo);
1597 	INP_WUNLOCK(inp);
1598 	return (error);
1599 }
1600 
1601 static void
1602 udp_close(struct socket *so)
1603 {
1604 	struct inpcb *inp;
1605 	struct inpcbinfo *pcbinfo;
1606 
1607 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1608 	inp = sotoinpcb(so);
1609 	KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1610 	INP_WLOCK(inp);
1611 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1612 		INP_HASH_WLOCK(pcbinfo);
1613 		in_pcbdisconnect(inp);
1614 		INP_HASH_WUNLOCK(pcbinfo);
1615 		soisdisconnected(so);
1616 	}
1617 	INP_WUNLOCK(inp);
1618 }
1619 
1620 static int
1621 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1622 {
1623 	struct epoch_tracker et;
1624 	struct inpcb *inp;
1625 	struct inpcbinfo *pcbinfo;
1626 	struct sockaddr_in *sin;
1627 	int error;
1628 
1629 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1630 	inp = sotoinpcb(so);
1631 	KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1632 
1633 	sin = (struct sockaddr_in *)nam;
1634 	if (sin->sin_family != AF_INET)
1635 		return (EAFNOSUPPORT);
1636 	if (sin->sin_len != sizeof(*sin))
1637 		return (EINVAL);
1638 
1639 	INP_WLOCK(inp);
1640 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
1641 		INP_WUNLOCK(inp);
1642 		return (EISCONN);
1643 	}
1644 	error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1645 	if (error != 0) {
1646 		INP_WUNLOCK(inp);
1647 		return (error);
1648 	}
1649 	NET_EPOCH_ENTER(et);
1650 	INP_HASH_WLOCK(pcbinfo);
1651 	error = in_pcbconnect(inp, sin, td->td_ucred);
1652 	INP_HASH_WUNLOCK(pcbinfo);
1653 	NET_EPOCH_EXIT(et);
1654 	if (error == 0)
1655 		soisconnected(so);
1656 	INP_WUNLOCK(inp);
1657 	return (error);
1658 }
1659 
1660 static void
1661 udp_detach(struct socket *so)
1662 {
1663 	struct inpcb *inp;
1664 
1665 	inp = sotoinpcb(so);
1666 	KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1667 	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1668 	    ("udp_detach: not disconnected"));
1669 	INP_WLOCK(inp);
1670 	in_pcbfree(inp);
1671 }
1672 
1673 int
1674 udp_disconnect(struct socket *so)
1675 {
1676 	struct inpcb *inp;
1677 	struct inpcbinfo *pcbinfo;
1678 
1679 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1680 	inp = sotoinpcb(so);
1681 	KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1682 	INP_WLOCK(inp);
1683 	if (inp->inp_faddr.s_addr == INADDR_ANY) {
1684 		INP_WUNLOCK(inp);
1685 		return (ENOTCONN);
1686 	}
1687 	INP_HASH_WLOCK(pcbinfo);
1688 	in_pcbdisconnect(inp);
1689 	INP_HASH_WUNLOCK(pcbinfo);
1690 	SOCK_LOCK(so);
1691 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
1692 	SOCK_UNLOCK(so);
1693 	INP_WUNLOCK(inp);
1694 	return (0);
1695 }
1696 #endif /* INET */
1697 
1698 int
1699 udp_shutdown(struct socket *so, enum shutdown_how how)
1700 {
1701 	int error;
1702 
1703 	SOCK_LOCK(so);
1704 	if (!(so->so_state & SS_ISCONNECTED))
1705 		/*
1706 		 * POSIX mandates us to just return ENOTCONN when shutdown(2) is
1707 		 * invoked on a datagram sockets, however historically we would
1708 		 * actually tear socket down.  This is known to be leveraged by
1709 		 * some applications to unblock process waiting in recv(2) by
1710 		 * other process that it shares that socket with.  Try to meet
1711 		 * both backward-compatibility and POSIX requirements by forcing
1712 		 * ENOTCONN but still flushing buffers and performing wakeup(9).
1713 		 *
1714 		 * XXXGL: it remains unknown what applications expect this
1715 		 * behavior and is this isolated to unix/dgram or inet/dgram or
1716 		 * both.  See: D10351, D3039.
1717 		 */
1718 		error = ENOTCONN;
1719 	else
1720 		error = 0;
1721 	SOCK_UNLOCK(so);
1722 
1723 	switch (how) {
1724 	case SHUT_RD:
1725 		sorflush(so);
1726 		break;
1727 	case SHUT_RDWR:
1728 		sorflush(so);
1729 		/* FALLTHROUGH */
1730 	case SHUT_WR:
1731 		socantsendmore(so);
1732 	}
1733 
1734 	return (error);
1735 }
1736 
1737 #ifdef INET
1738 #define	UDP_PROTOSW							\
1739 	.pr_type =		SOCK_DGRAM,				\
1740 	.pr_flags =		PR_ATOMIC | PR_ADDR | PR_CAPATTACH,	\
1741 	.pr_ctloutput =		udp_ctloutput,				\
1742 	.pr_abort =		udp_abort,				\
1743 	.pr_attach =		udp_attach,				\
1744 	.pr_bind =		udp_bind,				\
1745 	.pr_connect =		udp_connect,				\
1746 	.pr_control =		in_control,				\
1747 	.pr_detach =		udp_detach,				\
1748 	.pr_disconnect =	udp_disconnect,				\
1749 	.pr_peeraddr =		in_getpeeraddr,				\
1750 	.pr_send =		udp_send,				\
1751 	.pr_soreceive =		soreceive_dgram,			\
1752 	.pr_sosend =		sosend_dgram,				\
1753 	.pr_shutdown =		udp_shutdown,				\
1754 	.pr_sockaddr =		in_getsockaddr,				\
1755 	.pr_sosetlabel =	in_pcbsosetlabel,			\
1756 	.pr_close =		udp_close
1757 
1758 struct protosw udp_protosw = {
1759 	.pr_protocol =		IPPROTO_UDP,
1760 	UDP_PROTOSW
1761 };
1762 
1763 struct protosw udplite_protosw = {
1764 	.pr_protocol =		IPPROTO_UDPLITE,
1765 	UDP_PROTOSW
1766 };
1767 
1768 static void
1769 udp_init(void *arg __unused)
1770 {
1771 
1772 	IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1773 	IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1774 }
1775 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1776 #endif /* INET */
1777