xref: /freebsd/sys/netinet6/udp6_usrreq.c (revision e87ec409fa9b21abf79895837fe375ab3d7e408a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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 project 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 PROJECT 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 PROJECT 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  *	$KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $
37  *	$KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $
38  */
39 
40 /*-
41  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
42  *	The Regents of the University of California.
43  * All rights reserved.
44  *
45  * Redistribution and use in source and binary forms, with or without
46  * modification, are permitted provided that the following conditions
47  * are met:
48  * 1. Redistributions of source code must retain the above copyright
49  *    notice, this list of conditions and the following disclaimer.
50  * 2. Redistributions in binary form must reproduce the above copyright
51  *    notice, this list of conditions and the following disclaimer in the
52  *    documentation and/or other materials provided with the distribution.
53  * 3. Neither the name of the University nor the names of its contributors
54  *    may be used to endorse or promote products derived from this software
55  *    without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
58  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
59  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
60  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
61  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
62  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
63  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
64  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
65  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
66  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
67  * SUCH DAMAGE.
68  *
69  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
70  */
71 
72 #include <sys/cdefs.h>
73 __FBSDID("$FreeBSD$");
74 
75 #include "opt_inet.h"
76 #include "opt_inet6.h"
77 #include "opt_ipsec.h"
78 #include "opt_route.h"
79 #include "opt_rss.h"
80 
81 #include <sys/param.h>
82 #include <sys/jail.h>
83 #include <sys/kernel.h>
84 #include <sys/lock.h>
85 #include <sys/mbuf.h>
86 #include <sys/priv.h>
87 #include <sys/proc.h>
88 #include <sys/protosw.h>
89 #include <sys/sdt.h>
90 #include <sys/signalvar.h>
91 #include <sys/socket.h>
92 #include <sys/socketvar.h>
93 #include <sys/sx.h>
94 #include <sys/sysctl.h>
95 #include <sys/syslog.h>
96 #include <sys/systm.h>
97 
98 #include <net/if.h>
99 #include <net/if_var.h>
100 #include <net/if_types.h>
101 #include <net/route.h>
102 #include <net/rss_config.h>
103 
104 #include <netinet/in.h>
105 #include <netinet/in_kdtrace.h>
106 #include <netinet/in_pcb.h>
107 #include <netinet/in_systm.h>
108 #include <netinet/in_var.h>
109 #include <netinet/ip.h>
110 #include <netinet/ip6.h>
111 #include <netinet/icmp6.h>
112 #include <netinet/ip_var.h>
113 #include <netinet/udp.h>
114 #include <netinet/udp_var.h>
115 #include <netinet/udplite.h>
116 
117 #include <netinet6/ip6protosw.h>
118 #include <netinet6/ip6_var.h>
119 #include <netinet6/in6_fib.h>
120 #include <netinet6/in6_pcb.h>
121 #include <netinet6/in6_rss.h>
122 #include <netinet6/udp6_var.h>
123 #include <netinet6/scope6_var.h>
124 
125 #include <netipsec/ipsec_support.h>
126 
127 #include <security/mac/mac_framework.h>
128 
129 VNET_DEFINE(int, zero_checksum_port) = 0;
130 #define	V_zero_checksum_port	VNET(zero_checksum_port)
131 SYSCTL_INT(_net_inet6_udp6, OID_AUTO, rfc6935_port, CTLFLAG_VNET | CTLFLAG_RW,
132     &VNET_NAME(zero_checksum_port), 0,
133     "Zero UDP checksum allowed for traffic to/from this port.");
134 /*
135  * UDP protocol implementation.
136  * Per RFC 768, August, 1980.
137  */
138 
139 extern struct protosw	inetsw[];
140 static void		udp6_detach(struct socket *so);
141 
142 static int
143 udp6_append(struct inpcb *inp, struct mbuf *n, int off,
144     struct sockaddr_in6 *fromsa)
145 {
146 	struct socket *so;
147 	struct mbuf *opts = NULL, *tmp_opts;
148 	struct udpcb *up;
149 
150 	INP_LOCK_ASSERT(inp);
151 
152 	/*
153 	 * Engage the tunneling protocol.
154 	 */
155 	up = intoudpcb(inp);
156 	if (up->u_tun_func != NULL) {
157 		in_pcbref(inp);
158 		INP_RUNLOCK(inp);
159 		(*up->u_tun_func)(n, off, inp, (struct sockaddr *)&fromsa[0],
160 		    up->u_tun_ctx);
161 		INP_RLOCK(inp);
162 		return (in_pcbrele_rlocked(inp));
163 	}
164 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
165 	/* Check AH/ESP integrity. */
166 	if (IPSEC_ENABLED(ipv6)) {
167 		if (IPSEC_CHECK_POLICY(ipv6, n, inp) != 0) {
168 			m_freem(n);
169 			return (0);
170 		}
171 	}
172 #endif /* IPSEC */
173 #ifdef MAC
174 	if (mac_inpcb_check_deliver(inp, n) != 0) {
175 		m_freem(n);
176 		return (0);
177 	}
178 #endif
179 	opts = NULL;
180 	if (inp->inp_flags & INP_CONTROLOPTS ||
181 	    inp->inp_socket->so_options & SO_TIMESTAMP)
182 		ip6_savecontrol(inp, n, &opts);
183 	if ((inp->inp_vflag & INP_IPV6) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
184 		tmp_opts = sbcreatecontrol((caddr_t)&fromsa[1],
185                         sizeof(struct sockaddr_in6), IPV6_ORIGDSTADDR, IPPROTO_IPV6);
186                 if (tmp_opts) {
187                         if (opts) {
188                                 tmp_opts->m_next = opts;
189                                 opts = tmp_opts;
190                         } else
191                                 opts = tmp_opts;
192                 }
193 	}
194 	m_adj(n, off + sizeof(struct udphdr));
195 
196 	so = inp->inp_socket;
197 	SOCKBUF_LOCK(&so->so_rcv);
198 	if (sbappendaddr_locked(&so->so_rcv, (struct sockaddr *)&fromsa[0], n,
199 	    opts) == 0) {
200 		soroverflow_locked(so);
201 		m_freem(n);
202 		if (opts)
203 			m_freem(opts);
204 		UDPSTAT_INC(udps_fullsock);
205 	} else
206 		sorwakeup_locked(so);
207 	return (0);
208 }
209 
210 struct udp6_multi_match_ctx {
211 	struct ip6_hdr *ip6;
212 	struct udphdr *uh;
213 };
214 
215 static bool
216 udp6_multi_match(const struct inpcb *inp, void *v)
217 {
218 	struct udp6_multi_match_ctx *ctx = v;
219 
220 	if ((inp->inp_vflag & INP_IPV6) == 0)
221 		return(false);
222 	if (inp->inp_lport != ctx->uh->uh_dport)
223 		return(false);
224 	if (inp->inp_fport != 0 && inp->inp_fport != ctx->uh->uh_sport)
225 		return(false);
226 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
227 	    !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &ctx->ip6->ip6_dst))
228 		return (false);
229 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
230 	    (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &ctx->ip6->ip6_src) ||
231 	    inp->inp_fport != ctx->uh->uh_sport))
232 		return (false);
233 
234 	return (true);
235 }
236 
237 static int
238 udp6_multi_input(struct mbuf *m, int off, int proto,
239     struct sockaddr_in6 *fromsa)
240 {
241 	struct udp6_multi_match_ctx ctx;
242 	struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
243 	    INPLOOKUP_RLOCKPCB, udp6_multi_match, &ctx);
244 	struct inpcb *inp;
245 	struct ip6_moptions *imo;
246 	struct mbuf *n;
247 	int appends = 0;
248 
249 	/*
250 	 * In the event that laddr should be set to the link-local
251 	 * address (this happens in RIPng), the multicast address
252 	 * specified in the received packet will not match laddr.  To
253 	 * handle this situation, matching is relaxed if the
254 	 * receiving interface is the same as one specified in the
255 	 * socket and if the destination multicast address matches
256 	 * one of the multicast groups specified in the socket.
257 	 */
258 
259 	/*
260 	 * KAME note: traditionally we dropped udpiphdr from mbuf
261 	 * here.  We need udphdr for IPsec processing so we do that
262 	 * later.
263 	 */
264 	ctx.ip6 = mtod(m, struct ip6_hdr *);
265 	ctx.uh = (struct udphdr *)((char *)ctx.ip6 + off);
266 	while ((inp = inp_next(&inpi)) != NULL) {
267 		INP_RLOCK_ASSERT(inp);
268 		/*
269 		 * XXXRW: Because we weren't holding either the inpcb
270 		 * or the hash lock when we checked for a match
271 		 * before, we should probably recheck now that the
272 		 * inpcb lock is (supposed to be) held.
273 		 */
274 		/*
275 		 * Handle socket delivery policy for any-source
276 		 * and source-specific multicast. [RFC3678]
277 		 */
278 		if ((imo = inp->in6p_moptions) != NULL) {
279 			struct sockaddr_in6	 mcaddr;
280 			int			 blocked;
281 
282 			bzero(&mcaddr, sizeof(struct sockaddr_in6));
283 			mcaddr.sin6_len = sizeof(struct sockaddr_in6);
284 			mcaddr.sin6_family = AF_INET6;
285 			mcaddr.sin6_addr = ctx.ip6->ip6_dst;
286 
287 			blocked = im6o_mc_filter(imo, m->m_pkthdr.rcvif,
288 				(struct sockaddr *)&mcaddr,
289 				(struct sockaddr *)&fromsa[0]);
290 			if (blocked != MCAST_PASS) {
291 				if (blocked == MCAST_NOTGMEMBER)
292 					IP6STAT_INC(ip6s_notmember);
293 				if (blocked == MCAST_NOTSMEMBER ||
294 				    blocked == MCAST_MUTED)
295 					UDPSTAT_INC(udps_filtermcast);
296 				continue;
297 			}
298 		}
299 		if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
300 			if (proto == IPPROTO_UDPLITE)
301 				UDPLITE_PROBE(receive, NULL, inp, ctx.ip6,
302 				    inp, ctx.uh);
303 			else
304 				UDP_PROBE(receive, NULL, inp, ctx.ip6, inp,
305 				    ctx.uh);
306 			if (udp6_append(inp, n, off, fromsa)) {
307 				INP_RUNLOCK(inp);
308 				break;
309 			} else
310 				appends++;
311 		}
312 		/*
313 		 * Don't look for additional matches if this one does
314 		 * not have either the SO_REUSEPORT or SO_REUSEADDR
315 		 * socket options set.  This heuristic avoids
316 		 * searching through all pcbs in the common case of a
317 		 * non-shared port.  It assumes that an application
318 		 * will never clear these options after setting them.
319 		 */
320 		if ((inp->inp_socket->so_options &
321 		     (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
322 			INP_RUNLOCK(inp);
323 			break;
324 		}
325 	}
326 	m_freem(m);
327 
328 	if (appends == 0) {
329 		/*
330 		 * No matching pcb found; discard datagram.  (No need
331 		 * to send an ICMP Port Unreachable for a broadcast
332 		 * or multicast datgram.)
333 		 */
334 		UDPSTAT_INC(udps_noport);
335 		UDPSTAT_INC(udps_noportmcast);
336 	}
337 
338 	return (IPPROTO_DONE);
339 }
340 
341 int
342 udp6_input(struct mbuf **mp, int *offp, int proto)
343 {
344 	struct mbuf *m = *mp;
345 	struct ip6_hdr *ip6;
346 	struct udphdr *uh;
347 	struct inpcb *inp;
348 	struct inpcbinfo *pcbinfo;
349 	struct udpcb *up;
350 	int off = *offp;
351 	int cscov_partial;
352 	int plen, ulen;
353 	struct sockaddr_in6 fromsa[2];
354 	struct m_tag *fwd_tag;
355 	uint16_t uh_sum;
356 	uint8_t nxt;
357 
358 	NET_EPOCH_ASSERT();
359 
360 	if (m->m_len < off + sizeof(struct udphdr)) {
361 		m = m_pullup(m, off + sizeof(struct udphdr));
362 		if (m == NULL) {
363 			IP6STAT_INC(ip6s_exthdrtoolong);
364 			*mp = NULL;
365 			return (IPPROTO_DONE);
366 		}
367 	}
368 	ip6 = mtod(m, struct ip6_hdr *);
369 	uh = (struct udphdr *)((caddr_t)ip6 + off);
370 
371 	UDPSTAT_INC(udps_ipackets);
372 
373 	/*
374 	 * Destination port of 0 is illegal, based on RFC768.
375 	 */
376 	if (uh->uh_dport == 0)
377 		goto badunlocked;
378 
379 	plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
380 	ulen = ntohs((u_short)uh->uh_ulen);
381 
382 	nxt = proto;
383 	cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
384 	if (nxt == IPPROTO_UDPLITE) {
385 		/* Zero means checksum over the complete packet. */
386 		if (ulen == 0)
387 			ulen = plen;
388 		if (ulen == plen)
389 			cscov_partial = 0;
390 		if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
391 			/* XXX: What is the right UDPLite MIB counter? */
392 			goto badunlocked;
393 		}
394 		if (uh->uh_sum == 0) {
395 			/* XXX: What is the right UDPLite MIB counter? */
396 			goto badunlocked;
397 		}
398 	} else {
399 		if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
400 			UDPSTAT_INC(udps_badlen);
401 			goto badunlocked;
402 		}
403 		if (uh->uh_sum == 0) {
404 			UDPSTAT_INC(udps_nosum);
405 			/*
406 			 * dport 0 was rejected earlier so this is OK even if
407 			 * zero_checksum_port is 0 (which is its default value).
408 			 */
409 			if (ntohs(uh->uh_dport) == V_zero_checksum_port)
410 				goto skip_checksum;
411 			else
412 				goto badunlocked;
413 		}
414 	}
415 
416 	if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
417 	    !cscov_partial) {
418 		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
419 			uh_sum = m->m_pkthdr.csum_data;
420 		else
421 			uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
422 			    m->m_pkthdr.csum_data);
423 		uh_sum ^= 0xffff;
424 	} else
425 		uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
426 
427 	if (uh_sum != 0) {
428 		UDPSTAT_INC(udps_badsum);
429 		goto badunlocked;
430 	}
431 
432 skip_checksum:
433 	/*
434 	 * Construct sockaddr format source address.
435 	 */
436 	init_sin6(&fromsa[0], m, 0);
437 	fromsa[0].sin6_port = uh->uh_sport;
438 	init_sin6(&fromsa[1], m, 1);
439 	fromsa[1].sin6_port = uh->uh_dport;
440 
441 	pcbinfo = udp_get_inpcbinfo(nxt);
442 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))  {
443 		*mp = NULL;
444 		return (udp6_multi_input(m, off, proto, fromsa));
445 	}
446 
447 	/*
448 	 * Locate pcb for datagram.
449 	 */
450 
451 	/*
452 	 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
453 	 */
454 	if ((m->m_flags & M_IP6_NEXTHOP) &&
455 	    (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
456 		struct sockaddr_in6 *next_hop6;
457 
458 		next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
459 
460 		/*
461 		 * Transparently forwarded. Pretend to be the destination.
462 		 * Already got one like this?
463 		 */
464 		inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
465 		    uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
466 		    INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
467 		if (!inp) {
468 			/*
469 			 * It's new.  Try to find the ambushing socket.
470 			 * Because we've rewritten the destination address,
471 			 * any hardware-generated hash is ignored.
472 			 */
473 			inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
474 			    uh->uh_sport, &next_hop6->sin6_addr,
475 			    next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
476 			    uh->uh_dport, INPLOOKUP_WILDCARD |
477 			    INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
478 		}
479 		/* Remove the tag from the packet. We don't need it anymore. */
480 		m_tag_delete(m, fwd_tag);
481 		m->m_flags &= ~M_IP6_NEXTHOP;
482 	} else
483 		inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
484 		    uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
485 		    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
486 		    m->m_pkthdr.rcvif, m);
487 	if (inp == NULL) {
488 		if (V_udp_log_in_vain) {
489 			char ip6bufs[INET6_ADDRSTRLEN];
490 			char ip6bufd[INET6_ADDRSTRLEN];
491 
492 			log(LOG_INFO,
493 			    "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
494 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
495 			    ntohs(uh->uh_dport),
496 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
497 			    ntohs(uh->uh_sport));
498 		}
499 		if (nxt == IPPROTO_UDPLITE)
500 			UDPLITE_PROBE(receive, NULL, NULL, ip6, NULL, uh);
501 		else
502 			UDP_PROBE(receive, NULL, NULL, ip6, NULL, uh);
503 		UDPSTAT_INC(udps_noport);
504 		if (m->m_flags & M_MCAST) {
505 			printf("UDP6: M_MCAST is set in a unicast packet.\n");
506 			UDPSTAT_INC(udps_noportmcast);
507 			goto badunlocked;
508 		}
509 		if (V_udp_blackhole && (V_udp_blackhole_local ||
510 		    !in6_localaddr(&ip6->ip6_src)))
511 			goto badunlocked;
512 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
513 		*mp = NULL;
514 		return (IPPROTO_DONE);
515 	}
516 	INP_RLOCK_ASSERT(inp);
517 	up = intoudpcb(inp);
518 	if (cscov_partial) {
519 		if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
520 			INP_RUNLOCK(inp);
521 			m_freem(m);
522 			*mp = NULL;
523 			return (IPPROTO_DONE);
524 		}
525 	}
526 	if (nxt == IPPROTO_UDPLITE)
527 		UDPLITE_PROBE(receive, NULL, inp, ip6, inp, uh);
528 	else
529 		UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
530 	if (udp6_append(inp, m, off, fromsa) == 0)
531 		INP_RUNLOCK(inp);
532 	*mp = NULL;
533 	return (IPPROTO_DONE);
534 
535 badunlocked:
536 	m_freem(m);
537 	*mp = NULL;
538 	return (IPPROTO_DONE);
539 }
540 
541 static void
542 udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
543     struct inpcbinfo *pcbinfo)
544 {
545 	struct udphdr uh;
546 	struct ip6_hdr *ip6;
547 	struct mbuf *m;
548 	int off = 0;
549 	struct ip6ctlparam *ip6cp = NULL;
550 	const struct sockaddr_in6 *sa6_src = NULL;
551 	void *cmdarg;
552 	struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
553 	struct udp_portonly {
554 		u_int16_t uh_sport;
555 		u_int16_t uh_dport;
556 	} *uhp;
557 
558 	if (sa->sa_family != AF_INET6 ||
559 	    sa->sa_len != sizeof(struct sockaddr_in6))
560 		return;
561 
562 	if ((unsigned)cmd >= PRC_NCMDS)
563 		return;
564 	if (PRC_IS_REDIRECT(cmd))
565 		notify = in6_rtchange, d = NULL;
566 	else if (cmd == PRC_HOSTDEAD)
567 		d = NULL;
568 	else if (inet6ctlerrmap[cmd] == 0)
569 		return;
570 
571 	/* if the parameter is from icmp6, decode it. */
572 	if (d != NULL) {
573 		ip6cp = (struct ip6ctlparam *)d;
574 		m = ip6cp->ip6c_m;
575 		ip6 = ip6cp->ip6c_ip6;
576 		off = ip6cp->ip6c_off;
577 		cmdarg = ip6cp->ip6c_cmdarg;
578 		sa6_src = ip6cp->ip6c_src;
579 	} else {
580 		m = NULL;
581 		ip6 = NULL;
582 		cmdarg = NULL;
583 		sa6_src = &sa6_any;
584 	}
585 
586 	if (ip6) {
587 		/*
588 		 * XXX: We assume that when IPV6 is non NULL,
589 		 * M and OFF are valid.
590 		 */
591 
592 		/* Check if we can safely examine src and dst ports. */
593 		if (m->m_pkthdr.len < off + sizeof(*uhp))
594 			return;
595 
596 		bzero(&uh, sizeof(uh));
597 		m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
598 
599 		if (!PRC_IS_REDIRECT(cmd)) {
600 			/* Check to see if its tunneled */
601 			struct inpcb *inp;
602 			inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_dst,
603 			    uh.uh_dport, &ip6->ip6_src, uh.uh_sport,
604 			    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
605 			    m->m_pkthdr.rcvif, m);
606 			if (inp != NULL) {
607 				struct udpcb *up;
608 
609 				up = intoudpcb(inp);
610 				if (up->u_icmp_func) {
611 					/* Yes it is. */
612 					INP_RUNLOCK(inp);
613 					(*up->u_icmp_func)(cmd, (struct sockaddr *)ip6cp->ip6c_src,
614 					      d, up->u_tun_ctx);
615 					return;
616 				} else {
617 					/* Can't find it. */
618 					INP_RUNLOCK(inp);
619 				}
620 			}
621 		}
622 		(void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
623 		    (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
624 		    cmdarg, notify);
625 	} else
626 		(void)in6_pcbnotify(pcbinfo, sa, 0,
627 		    (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
628 }
629 
630 void
631 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
632 {
633 
634 	return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
635 }
636 
637 void
638 udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
639 {
640 
641 	return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
642 }
643 
644 static int
645 udp6_getcred(SYSCTL_HANDLER_ARGS)
646 {
647 	struct xucred xuc;
648 	struct sockaddr_in6 addrs[2];
649 	struct epoch_tracker et;
650 	struct inpcb *inp;
651 	int error;
652 
653 	error = priv_check(req->td, PRIV_NETINET_GETCRED);
654 	if (error)
655 		return (error);
656 
657 	if (req->newlen != sizeof(addrs))
658 		return (EINVAL);
659 	if (req->oldlen != sizeof(struct xucred))
660 		return (EINVAL);
661 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
662 	if (error)
663 		return (error);
664 	if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
665 	    (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
666 		return (error);
667 	}
668 	NET_EPOCH_ENTER(et);
669 	inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
670 	    addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
671 	    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
672 	NET_EPOCH_EXIT(et);
673 	if (inp != NULL) {
674 		INP_RLOCK_ASSERT(inp);
675 		if (inp->inp_socket == NULL)
676 			error = ENOENT;
677 		if (error == 0)
678 			error = cr_canseesocket(req->td->td_ucred,
679 			    inp->inp_socket);
680 		if (error == 0)
681 			cru2x(inp->inp_cred, &xuc);
682 		INP_RUNLOCK(inp);
683 	} else
684 		error = ENOENT;
685 	if (error == 0)
686 		error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
687 	return (error);
688 }
689 
690 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred,
691     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_MPSAFE,
692     0, 0, udp6_getcred, "S,xucred",
693     "Get the xucred of a UDP6 connection");
694 
695 static int
696 udp6_output(struct socket *so, int flags_arg, struct mbuf *m,
697     struct sockaddr *addr6, struct mbuf *control, struct thread *td)
698 {
699 	struct inpcb *inp;
700 	struct ip6_hdr *ip6;
701 	struct udphdr *udp6;
702 	struct in6_addr *laddr, *faddr, in6a;
703 	struct ip6_pktopts *optp, opt;
704 	struct sockaddr_in6 *sin6, tmp;
705 	struct epoch_tracker et;
706 	int cscov_partial, error, flags, hlen, scope_ambiguous;
707 	u_int32_t ulen, plen;
708 	uint16_t cscov;
709 	u_short fport;
710 	uint8_t nxt;
711 
712 	/* addr6 has been validated in udp6_send(). */
713 	sin6 = (struct sockaddr_in6 *)addr6;
714 
715 	/*
716 	 * In contrast to to IPv4 we do not validate the max. packet length
717 	 * here due to IPv6 Jumbograms (RFC2675).
718 	 */
719 
720 	scope_ambiguous = 0;
721 	if (sin6) {
722 		/* Protect *addr6 from overwrites. */
723 		tmp = *sin6;
724 		sin6 = &tmp;
725 
726 		/*
727 		 * Application should provide a proper zone ID or the use of
728 		 * default zone IDs should be enabled.  Unfortunately, some
729 		 * applications do not behave as it should, so we need a
730 		 * workaround.  Even if an appropriate ID is not determined,
731 		 * we'll see if we can determine the outgoing interface.  If we
732 		 * can, determine the zone ID based on the interface below.
733 		 */
734 		if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
735 			scope_ambiguous = 1;
736 		if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0) {
737 			if (control)
738 				m_freem(control);
739 			m_freem(m);
740 			return (error);
741 		}
742 	}
743 
744 	inp = sotoinpcb(so);
745 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
746 	/*
747 	 * In the following cases we want a write lock on the inp for either
748 	 * local operations or for possible route cache updates in the IPv6
749 	 * output path:
750 	 * - on connected sockets (sin6 is NULL) for route cache updates,
751 	 * - when we are not bound to an address and source port (it is
752 	 *   in6_pcbsetport() which will require the write lock).
753 	 *
754 	 * We check the inp fields before actually locking the inp, so
755 	 * here exists a race, and we may WLOCK the inp and end with already
756 	 * bound one by other thread. This is fine.
757 	 */
758 	if (sin6 == NULL || (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
759 	    inp->inp_lport == 0))
760 		INP_WLOCK(inp);
761 	else
762 		INP_RLOCK(inp);
763 
764 	nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
765 	    IPPROTO_UDP : IPPROTO_UDPLITE;
766 
767 #ifdef INET
768 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
769 		int hasv4addr;
770 
771 		if (sin6 == NULL)
772 			hasv4addr = (inp->inp_vflag & INP_IPV4);
773 		else
774 			hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
775 			    ? 1 : 0;
776 		if (hasv4addr) {
777 			struct pr_usrreqs *pru;
778 
779 			/*
780 			 * XXXRW: We release UDP-layer locks before calling
781 			 * udp_send() in order to avoid recursion.  However,
782 			 * this does mean there is a short window where inp's
783 			 * fields are unstable.  Could this lead to a
784 			 * potential race in which the factors causing us to
785 			 * select the UDPv4 output routine are invalidated?
786 			 */
787 			INP_UNLOCK(inp);
788 			if (sin6)
789 				in6_sin6_2_sin_in_sock((struct sockaddr *)sin6);
790 			pru = inetsw[ip_protox[nxt]].pr_usrreqs;
791 			/* addr will just be freed in sendit(). */
792 			return ((*pru->pru_send)(so, flags_arg | PRUS_IPV6, m,
793 			    (struct sockaddr *)sin6, control, td));
794 		}
795 	} else
796 #endif
797 	if (sin6 && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
798 		/*
799 		 * Given this is either an IPv6-only socket or no INET is
800 		 * supported we will fail the send if the given destination
801 		 * address is a v4mapped address.
802 		 *
803 		 * XXXGL: do we leak m and control?
804 		 */
805 		INP_UNLOCK(inp);
806 		return (EINVAL);
807 	}
808 
809 	NET_EPOCH_ENTER(et);
810 	if (control) {
811 		if ((error = ip6_setpktopts(control, &opt,
812 		    inp->in6p_outputopts, td->td_ucred, nxt)) != 0) {
813 			goto release;
814 		}
815 		optp = &opt;
816 	} else
817 		optp = inp->in6p_outputopts;
818 
819 	if (sin6) {
820 		/*
821 		 * Since we saw no essential reason for calling in_pcbconnect,
822 		 * we get rid of such kind of logic, and call in6_selectsrc
823 		 * and in6_pcbsetport in order to fill in the local address
824 		 * and the local port.
825 		 */
826 		if (sin6->sin6_port == 0) {
827 			error = EADDRNOTAVAIL;
828 			goto release;
829 		}
830 
831 		if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
832 			/* how about ::ffff:0.0.0.0 case? */
833 			error = EISCONN;
834 			goto release;
835 		}
836 
837 		/*
838 		 * Given we handle the v4mapped case in the INET block above
839 		 * assert here that it must not happen anymore.
840 		 */
841 		KASSERT(!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr),
842 		    ("%s: sin6(%p)->sin6_addr is v4mapped which we "
843 		    "should have handled.", __func__, sin6));
844 
845 		/* This only requires read-locking. */
846 		error = in6_selectsrc_socket(sin6, optp, inp,
847 		    td->td_ucred, scope_ambiguous, &in6a, NULL);
848 		if (error)
849 			goto release;
850 		laddr = &in6a;
851 
852 		if (inp->inp_lport == 0) {
853 			struct inpcbinfo *pcbinfo;
854 
855 			INP_WLOCK_ASSERT(inp);
856 
857 			pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
858 			INP_HASH_WLOCK(pcbinfo);
859 			error = in6_pcbsetport(laddr, inp, td->td_ucred);
860 			INP_HASH_WUNLOCK(pcbinfo);
861 			if (error != 0) {
862 				/* Undo an address bind that may have occurred. */
863 				inp->in6p_laddr = in6addr_any;
864 				goto release;
865 			}
866 		}
867 		faddr = &sin6->sin6_addr;
868 		fport = sin6->sin6_port; /* allow 0 port */
869 
870 	} else {
871 		if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
872 			error = ENOTCONN;
873 			goto release;
874 		}
875 		laddr = &inp->in6p_laddr;
876 		faddr = &inp->in6p_faddr;
877 		fport = inp->inp_fport;
878 	}
879 
880 	ulen = m->m_pkthdr.len;
881 	plen = sizeof(struct udphdr) + ulen;
882 	hlen = sizeof(struct ip6_hdr);
883 
884 	/*
885 	 * Calculate data length and get a mbuf
886 	 * for UDP and IP6 headers.
887 	 */
888 	M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
889 	if (m == NULL) {
890 		error = ENOBUFS;
891 		goto release;
892 	}
893 
894 	/*
895 	 * Stuff checksum and output datagram.
896 	 */
897 	cscov = cscov_partial = 0;
898 	udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
899 	udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
900 	udp6->uh_dport = fport;
901 	if (nxt == IPPROTO_UDPLITE) {
902 		struct udpcb *up;
903 
904 		up = intoudpcb(inp);
905 		cscov = up->u_txcslen;
906 		if (cscov >= plen)
907 			cscov = 0;
908 		udp6->uh_ulen = htons(cscov);
909 		/*
910 		 * For UDP-Lite, checksum coverage length of zero means
911 		 * the entire UDPLite packet is covered by the checksum.
912 		 */
913 		cscov_partial = (cscov == 0) ? 0 : 1;
914 	} else if (plen <= 0xffff)
915 		udp6->uh_ulen = htons((u_short)plen);
916 	else
917 		udp6->uh_ulen = 0;
918 	udp6->uh_sum = 0;
919 
920 	ip6 = mtod(m, struct ip6_hdr *);
921 	ip6->ip6_flow	= inp->inp_flow & IPV6_FLOWINFO_MASK;
922 	ip6->ip6_vfc	&= ~IPV6_VERSION_MASK;
923 	ip6->ip6_vfc	|= IPV6_VERSION;
924 	ip6->ip6_plen	= htons((u_short)plen);
925 	ip6->ip6_nxt	= nxt;
926 	ip6->ip6_hlim	= in6_selecthlim(inp, NULL);
927 	ip6->ip6_src	= *laddr;
928 	ip6->ip6_dst	= *faddr;
929 
930 #ifdef MAC
931 	mac_inpcb_create_mbuf(inp, m);
932 #endif
933 
934 	if (cscov_partial) {
935 		if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
936 		    sizeof(struct ip6_hdr), plen, cscov)) == 0)
937 			udp6->uh_sum = 0xffff;
938 	} else {
939 		udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
940 		m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
941 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
942 	}
943 
944 	flags = 0;
945 #if defined(ROUTE_MPATH) || defined(RSS)
946 	if (CALC_FLOWID_OUTBOUND_SENDTO) {
947 		uint32_t hash_type, hash_val;
948 		uint8_t pr;
949 
950 		pr = inp->inp_socket->so_proto->pr_protocol;
951 
952 		hash_val = fib6_calc_packet_hash(laddr, faddr,
953 		    inp->inp_lport, fport, pr, &hash_type);
954 		m->m_pkthdr.flowid = hash_val;
955 		M_HASHTYPE_SET(m, hash_type);
956 	}
957 	/* do not use inp flowid */
958 	flags |= IP_NODEFAULTFLOWID;
959 #endif
960 
961 	UDPSTAT_INC(udps_opackets);
962 	if (nxt == IPPROTO_UDPLITE)
963 		UDPLITE_PROBE(send, NULL, inp, ip6, inp, udp6);
964 	else
965 		UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
966 	error = ip6_output(m, optp,
967 	    INP_WLOCKED(inp) ? &inp->inp_route6 : NULL, flags,
968 	    inp->in6p_moptions, NULL, inp);
969 	INP_UNLOCK(inp);
970 	NET_EPOCH_EXIT(et);
971 
972 	if (control) {
973 		ip6_clearpktopts(&opt, -1);
974 		m_freem(control);
975 	}
976 	return (error);
977 
978 release:
979 	INP_UNLOCK(inp);
980 	NET_EPOCH_EXIT(et);
981 	if (control) {
982 		ip6_clearpktopts(&opt, -1);
983 		m_freem(control);
984 	}
985 	m_freem(m);
986 
987 	return (error);
988 }
989 
990 static void
991 udp6_abort(struct socket *so)
992 {
993 	struct inpcb *inp;
994 	struct inpcbinfo *pcbinfo;
995 
996 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
997 	inp = sotoinpcb(so);
998 	KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
999 
1000 	INP_WLOCK(inp);
1001 #ifdef INET
1002 	if (inp->inp_vflag & INP_IPV4) {
1003 		struct pr_usrreqs *pru;
1004 		uint8_t nxt;
1005 
1006 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1007 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1008 		INP_WUNLOCK(inp);
1009 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1010 		(*pru->pru_abort)(so);
1011 		return;
1012 	}
1013 #endif
1014 
1015 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1016 		INP_HASH_WLOCK(pcbinfo);
1017 		in6_pcbdisconnect(inp);
1018 		inp->in6p_laddr = in6addr_any;
1019 		INP_HASH_WUNLOCK(pcbinfo);
1020 		soisdisconnected(so);
1021 	}
1022 	INP_WUNLOCK(inp);
1023 }
1024 
1025 static int
1026 udp6_attach(struct socket *so, int proto, struct thread *td)
1027 {
1028 	struct inpcb *inp;
1029 	struct inpcbinfo *pcbinfo;
1030 	int error;
1031 
1032 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1033 	inp = sotoinpcb(so);
1034 	KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
1035 
1036 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1037 		error = soreserve(so, udp_sendspace, udp_recvspace);
1038 		if (error)
1039 			return (error);
1040 	}
1041 	error = in_pcballoc(so, pcbinfo);
1042 	if (error)
1043 		return (error);
1044 	inp = (struct inpcb *)so->so_pcb;
1045 	inp->inp_vflag |= INP_IPV6;
1046 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
1047 		inp->inp_vflag |= INP_IPV4;
1048 	inp->in6p_hops = -1;	/* use kernel default */
1049 	inp->in6p_cksum = -1;	/* just to be sure */
1050 	/*
1051 	 * XXX: ugly!!
1052 	 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1053 	 * because the socket may be bound to an IPv6 wildcard address,
1054 	 * which may match an IPv4-mapped IPv6 address.
1055 	 */
1056 	inp->inp_ip_ttl = V_ip_defttl;
1057 
1058 	error = udp_newudpcb(inp);
1059 	if (error) {
1060 		in_pcbdetach(inp);
1061 		in_pcbfree(inp);
1062 		return (error);
1063 	}
1064 	INP_WUNLOCK(inp);
1065 	return (0);
1066 }
1067 
1068 static int
1069 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1070 {
1071 	struct inpcb *inp;
1072 	struct inpcbinfo *pcbinfo;
1073 	int error;
1074 	u_char vflagsav;
1075 
1076 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1077 	inp = sotoinpcb(so);
1078 	KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
1079 
1080 	if (nam->sa_family != AF_INET6)
1081 		return (EAFNOSUPPORT);
1082 	if (nam->sa_len != sizeof(struct sockaddr_in6))
1083 		return (EINVAL);
1084 
1085 	INP_WLOCK(inp);
1086 	INP_HASH_WLOCK(pcbinfo);
1087 	vflagsav = inp->inp_vflag;
1088 	inp->inp_vflag &= ~INP_IPV4;
1089 	inp->inp_vflag |= INP_IPV6;
1090 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1091 		struct sockaddr_in6 *sin6_p;
1092 
1093 		sin6_p = (struct sockaddr_in6 *)nam;
1094 
1095 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
1096 			inp->inp_vflag |= INP_IPV4;
1097 #ifdef INET
1098 		else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
1099 			struct sockaddr_in sin;
1100 
1101 			in6_sin6_2_sin(&sin, sin6_p);
1102 			inp->inp_vflag |= INP_IPV4;
1103 			inp->inp_vflag &= ~INP_IPV6;
1104 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
1105 			    td->td_ucred);
1106 			goto out;
1107 		}
1108 #endif
1109 	}
1110 
1111 	error = in6_pcbbind(inp, nam, td->td_ucred);
1112 #ifdef INET
1113 out:
1114 #endif
1115 	if (error != 0)
1116 		inp->inp_vflag = vflagsav;
1117 	INP_HASH_WUNLOCK(pcbinfo);
1118 	INP_WUNLOCK(inp);
1119 	return (error);
1120 }
1121 
1122 static void
1123 udp6_close(struct socket *so)
1124 {
1125 	struct inpcb *inp;
1126 	struct inpcbinfo *pcbinfo;
1127 
1128 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1129 	inp = sotoinpcb(so);
1130 	KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
1131 
1132 	INP_WLOCK(inp);
1133 #ifdef INET
1134 	if (inp->inp_vflag & INP_IPV4) {
1135 		struct pr_usrreqs *pru;
1136 		uint8_t nxt;
1137 
1138 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1139 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1140 		INP_WUNLOCK(inp);
1141 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1142 		(*pru->pru_disconnect)(so);
1143 		return;
1144 	}
1145 #endif
1146 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1147 		INP_HASH_WLOCK(pcbinfo);
1148 		in6_pcbdisconnect(inp);
1149 		inp->in6p_laddr = in6addr_any;
1150 		INP_HASH_WUNLOCK(pcbinfo);
1151 		soisdisconnected(so);
1152 	}
1153 	INP_WUNLOCK(inp);
1154 }
1155 
1156 static int
1157 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1158 {
1159 #ifdef INET
1160 	struct epoch_tracker et;
1161 #endif
1162 	struct inpcb *inp;
1163 	struct inpcbinfo *pcbinfo;
1164 	struct sockaddr_in6 *sin6;
1165 	int error;
1166 	u_char vflagsav;
1167 
1168 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1169 	inp = sotoinpcb(so);
1170 	KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
1171 
1172 	sin6 = (struct sockaddr_in6 *)nam;
1173 	if (sin6->sin6_family != AF_INET6)
1174 		return (EAFNOSUPPORT);
1175 	if (sin6->sin6_len != sizeof(*sin6))
1176 		return (EINVAL);
1177 
1178 	/*
1179 	 * XXXRW: Need to clarify locking of v4/v6 flags.
1180 	 */
1181 	INP_WLOCK(inp);
1182 #ifdef INET
1183 	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1184 		struct sockaddr_in sin;
1185 
1186 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1187 			error = EINVAL;
1188 			goto out;
1189 		}
1190 		if ((inp->inp_vflag & INP_IPV4) == 0) {
1191 			error = EAFNOSUPPORT;
1192 			goto out;
1193 		}
1194 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
1195 			error = EISCONN;
1196 			goto out;
1197 		}
1198 		in6_sin6_2_sin(&sin, sin6);
1199 		error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
1200 		if (error != 0)
1201 			goto out;
1202 		vflagsav = inp->inp_vflag;
1203 		inp->inp_vflag |= INP_IPV4;
1204 		inp->inp_vflag &= ~INP_IPV6;
1205 		NET_EPOCH_ENTER(et);
1206 		INP_HASH_WLOCK(pcbinfo);
1207 		error = in_pcbconnect(inp, (struct sockaddr *)&sin,
1208 		    td->td_ucred, true);
1209 		INP_HASH_WUNLOCK(pcbinfo);
1210 		NET_EPOCH_EXIT(et);
1211 		/*
1212 		 * If connect succeeds, mark socket as connected. If
1213 		 * connect fails and socket is unbound, reset inp_vflag
1214 		 * field.
1215 		 */
1216 		if (error == 0)
1217 			soisconnected(so);
1218 		else if (inp->inp_laddr.s_addr == INADDR_ANY &&
1219 		    inp->inp_lport == 0)
1220 			inp->inp_vflag = vflagsav;
1221 		goto out;
1222 	} else {
1223 		if ((inp->inp_vflag & INP_IPV6) == 0) {
1224 			error = EAFNOSUPPORT;
1225 			goto out;
1226 		}
1227 	}
1228 #endif
1229 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1230 		error = EISCONN;
1231 		goto out;
1232 	}
1233 	error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
1234 	if (error != 0)
1235 		goto out;
1236 	vflagsav = inp->inp_vflag;
1237 	inp->inp_vflag &= ~INP_IPV4;
1238 	inp->inp_vflag |= INP_IPV6;
1239 	INP_HASH_WLOCK(pcbinfo);
1240 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1241 	INP_HASH_WUNLOCK(pcbinfo);
1242 	/*
1243 	 * If connect succeeds, mark socket as connected. If
1244 	 * connect fails and socket is unbound, reset inp_vflag
1245 	 * field.
1246 	 */
1247 	if (error == 0)
1248 		soisconnected(so);
1249 	else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
1250 	    inp->inp_lport == 0)
1251 		inp->inp_vflag = vflagsav;
1252 out:
1253 	INP_WUNLOCK(inp);
1254 	return (error);
1255 }
1256 
1257 static void
1258 udp6_detach(struct socket *so)
1259 {
1260 	struct inpcb *inp;
1261 	struct udpcb *up;
1262 
1263 	inp = sotoinpcb(so);
1264 	KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
1265 
1266 	INP_WLOCK(inp);
1267 	up = intoudpcb(inp);
1268 	KASSERT(up != NULL, ("%s: up == NULL", __func__));
1269 	in_pcbdetach(inp);
1270 	in_pcbfree(inp);
1271 	udp_discardcb(up);
1272 }
1273 
1274 static int
1275 udp6_disconnect(struct socket *so)
1276 {
1277 	struct inpcb *inp;
1278 	struct inpcbinfo *pcbinfo;
1279 
1280 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1281 	inp = sotoinpcb(so);
1282 	KASSERT(inp != NULL, ("udp6_disconnect: inp == NULL"));
1283 
1284 	INP_WLOCK(inp);
1285 #ifdef INET
1286 	if (inp->inp_vflag & INP_IPV4) {
1287 		struct pr_usrreqs *pru;
1288 		uint8_t nxt;
1289 
1290 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1291 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1292 		INP_WUNLOCK(inp);
1293 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1294 		(void)(*pru->pru_disconnect)(so);
1295 		return (0);
1296 	}
1297 #endif
1298 
1299 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1300 		INP_WUNLOCK(inp);
1301 		return (ENOTCONN);
1302 	}
1303 
1304 	INP_HASH_WLOCK(pcbinfo);
1305 	in6_pcbdisconnect(inp);
1306 	inp->in6p_laddr = in6addr_any;
1307 	INP_HASH_WUNLOCK(pcbinfo);
1308 	SOCK_LOCK(so);
1309 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
1310 	SOCK_UNLOCK(so);
1311 	INP_WUNLOCK(inp);
1312 	return (0);
1313 }
1314 
1315 static int
1316 udp6_send(struct socket *so, int flags, struct mbuf *m,
1317     struct sockaddr *addr, struct mbuf *control, struct thread *td)
1318 {
1319 	int error;
1320 
1321 	if (addr) {
1322 		if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1323 			error = EINVAL;
1324 			goto bad;
1325 		}
1326 		if (addr->sa_family != AF_INET6) {
1327 			error = EAFNOSUPPORT;
1328 			goto bad;
1329 		}
1330 	}
1331 
1332 	return (udp6_output(so, flags, m, addr, control, td));
1333 
1334 bad:
1335 	if (control)
1336 		m_freem(control);
1337 	m_freem(m);
1338 	return (error);
1339 }
1340 
1341 struct pr_usrreqs udp6_usrreqs = {
1342 	.pru_abort =		udp6_abort,
1343 	.pru_attach =		udp6_attach,
1344 	.pru_bind =		udp6_bind,
1345 	.pru_connect =		udp6_connect,
1346 	.pru_control =		in6_control,
1347 	.pru_detach =		udp6_detach,
1348 	.pru_disconnect =	udp6_disconnect,
1349 	.pru_peeraddr =		in6_mapped_peeraddr,
1350 	.pru_send =		udp6_send,
1351 	.pru_shutdown =		udp_shutdown,
1352 	.pru_sockaddr =		in6_mapped_sockaddr,
1353 	.pru_soreceive =	soreceive_dgram,
1354 	.pru_sosend =		sosend_dgram,
1355 	.pru_sosetlabel =	in_pcbsosetlabel,
1356 	.pru_close =		udp6_close
1357 };
1358