xref: /freebsd/sys/netinet6/udp6_usrreq.c (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
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 		SOCKBUF_UNLOCK(&so->so_rcv);
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 int
211 udp6_input(struct mbuf **mp, int *offp, int proto)
212 {
213 	struct mbuf *m = *mp;
214 	struct ifnet *ifp;
215 	struct ip6_hdr *ip6;
216 	struct udphdr *uh;
217 	struct inpcb *inp;
218 	struct inpcbinfo *pcbinfo;
219 	struct udpcb *up;
220 	int off = *offp;
221 	int cscov_partial;
222 	int plen, ulen;
223 	struct sockaddr_in6 fromsa[2];
224 	struct m_tag *fwd_tag;
225 	uint16_t uh_sum;
226 	uint8_t nxt;
227 
228 	NET_EPOCH_ASSERT();
229 
230 	ifp = m->m_pkthdr.rcvif;
231 
232 	if (m->m_len < off + sizeof(struct udphdr)) {
233 		m = m_pullup(m, off + sizeof(struct udphdr));
234 		if (m == NULL) {
235 			IP6STAT_INC(ip6s_exthdrtoolong);
236 			*mp = NULL;
237 			return (IPPROTO_DONE);
238 		}
239 	}
240 	ip6 = mtod(m, struct ip6_hdr *);
241 	uh = (struct udphdr *)((caddr_t)ip6 + off);
242 
243 	UDPSTAT_INC(udps_ipackets);
244 
245 	/*
246 	 * Destination port of 0 is illegal, based on RFC768.
247 	 */
248 	if (uh->uh_dport == 0)
249 		goto badunlocked;
250 
251 	plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
252 	ulen = ntohs((u_short)uh->uh_ulen);
253 
254 	nxt = proto;
255 	cscov_partial = (nxt == IPPROTO_UDPLITE) ? 1 : 0;
256 	if (nxt == IPPROTO_UDPLITE) {
257 		/* Zero means checksum over the complete packet. */
258 		if (ulen == 0)
259 			ulen = plen;
260 		if (ulen == plen)
261 			cscov_partial = 0;
262 		if ((ulen < sizeof(struct udphdr)) || (ulen > plen)) {
263 			/* XXX: What is the right UDPLite MIB counter? */
264 			goto badunlocked;
265 		}
266 		if (uh->uh_sum == 0) {
267 			/* XXX: What is the right UDPLite MIB counter? */
268 			goto badunlocked;
269 		}
270 	} else {
271 		if ((ulen < sizeof(struct udphdr)) || (plen != ulen)) {
272 			UDPSTAT_INC(udps_badlen);
273 			goto badunlocked;
274 		}
275 		if (uh->uh_sum == 0) {
276 			UDPSTAT_INC(udps_nosum);
277 			/*
278 			 * dport 0 was rejected earlier so this is OK even if
279 			 * zero_checksum_port is 0 (which is its default value).
280 			 */
281 			if (ntohs(uh->uh_dport) == V_zero_checksum_port)
282 				goto skip_checksum;
283 			else
284 				goto badunlocked;
285 		}
286 	}
287 
288 	if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) &&
289 	    !cscov_partial) {
290 		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
291 			uh_sum = m->m_pkthdr.csum_data;
292 		else
293 			uh_sum = in6_cksum_pseudo(ip6, ulen, nxt,
294 			    m->m_pkthdr.csum_data);
295 		uh_sum ^= 0xffff;
296 	} else
297 		uh_sum = in6_cksum_partial(m, nxt, off, plen, ulen);
298 
299 	if (uh_sum != 0) {
300 		UDPSTAT_INC(udps_badsum);
301 		goto badunlocked;
302 	}
303 
304 skip_checksum:
305 	/*
306 	 * Construct sockaddr format source address.
307 	 */
308 	init_sin6(&fromsa[0], m, 0);
309 	fromsa[0].sin6_port = uh->uh_sport;
310 	init_sin6(&fromsa[1], m, 1);
311 	fromsa[1].sin6_port = uh->uh_dport;
312 
313 	pcbinfo = udp_get_inpcbinfo(nxt);
314 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
315 		struct inpcb *last;
316 		struct inpcbhead *pcblist;
317 		struct ip6_moptions *imo;
318 
319 		/*
320 		 * In the event that laddr should be set to the link-local
321 		 * address (this happens in RIPng), the multicast address
322 		 * specified in the received packet will not match laddr.  To
323 		 * handle this situation, matching is relaxed if the
324 		 * receiving interface is the same as one specified in the
325 		 * socket and if the destination multicast address matches
326 		 * one of the multicast groups specified in the socket.
327 		 */
328 
329 		/*
330 		 * KAME note: traditionally we dropped udpiphdr from mbuf
331 		 * here.  We need udphdr for IPsec processing so we do that
332 		 * later.
333 		 */
334 		pcblist = udp_get_pcblist(nxt);
335 		last = NULL;
336 		CK_LIST_FOREACH(inp, pcblist, inp_list) {
337 			if ((inp->inp_vflag & INP_IPV6) == 0)
338 				continue;
339 			if (inp->inp_lport != uh->uh_dport)
340 				continue;
341 			if (inp->inp_fport != 0 &&
342 			    inp->inp_fport != uh->uh_sport)
343 				continue;
344 			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
345 				if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
346 							&ip6->ip6_dst))
347 					continue;
348 			}
349 			if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
350 				if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
351 							&ip6->ip6_src) ||
352 				    inp->inp_fport != uh->uh_sport)
353 					continue;
354 			}
355 
356 			/*
357 			 * XXXRW: Because we weren't holding either the inpcb
358 			 * or the hash lock when we checked for a match
359 			 * before, we should probably recheck now that the
360 			 * inpcb lock is (supposed to be) held.
361 			 */
362 
363 			/*
364 			 * Handle socket delivery policy for any-source
365 			 * and source-specific multicast. [RFC3678]
366 			 */
367 			imo = inp->in6p_moptions;
368 			if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
369 				struct sockaddr_in6	 mcaddr;
370 				int			 blocked;
371 
372 				INP_RLOCK(inp);
373 				if (__predict_false(inp->inp_flags2 & INP_FREED)) {
374 					INP_RUNLOCK(inp);
375 					continue;
376 				}
377 
378 				bzero(&mcaddr, sizeof(struct sockaddr_in6));
379 				mcaddr.sin6_len = sizeof(struct sockaddr_in6);
380 				mcaddr.sin6_family = AF_INET6;
381 				mcaddr.sin6_addr = ip6->ip6_dst;
382 
383 				blocked = im6o_mc_filter(imo, ifp,
384 					(struct sockaddr *)&mcaddr,
385 					(struct sockaddr *)&fromsa[0]);
386 				if (blocked != MCAST_PASS) {
387 					if (blocked == MCAST_NOTGMEMBER)
388 						IP6STAT_INC(ip6s_notmember);
389 					if (blocked == MCAST_NOTSMEMBER ||
390 					    blocked == MCAST_MUTED)
391 						UDPSTAT_INC(udps_filtermcast);
392 					INP_RUNLOCK(inp); /* XXX */
393 					continue;
394 				}
395 
396 				INP_RUNLOCK(inp);
397 			}
398 			if (last != NULL) {
399 				struct mbuf *n;
400 
401 				if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
402 				    NULL) {
403 					INP_RLOCK(last);
404 					if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
405 						if (nxt == IPPROTO_UDPLITE)
406 							UDPLITE_PROBE(receive, NULL, last,
407 							    ip6, last, uh);
408 						else
409 							UDP_PROBE(receive, NULL, last,
410 							    ip6, last, uh);
411 						if (udp6_append(last, n, off, fromsa)) {
412 							/* XXX-BZ do we leak m here? */
413 							*mp = NULL;
414 							return (IPPROTO_DONE);
415 						}
416 					}
417 					INP_RUNLOCK(last);
418 				}
419 			}
420 			last = inp;
421 			/*
422 			 * Don't look for additional matches if this one does
423 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
424 			 * socket options set.  This heuristic avoids
425 			 * searching through all pcbs in the common case of a
426 			 * non-shared port.  It assumes that an application
427 			 * will never clear these options after setting them.
428 			 */
429 			if ((last->inp_socket->so_options &
430 			     (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0)
431 				break;
432 		}
433 
434 		if (last == NULL) {
435 			/*
436 			 * No matching pcb found; discard datagram.  (No need
437 			 * to send an ICMP Port Unreachable for a broadcast
438 			 * or multicast datgram.)
439 			 */
440 			UDPSTAT_INC(udps_noport);
441 			UDPSTAT_INC(udps_noportmcast);
442 			goto badunlocked;
443 		}
444 		INP_RLOCK(last);
445 		if (__predict_true(last->inp_flags2 & INP_FREED) == 0) {
446 			if (nxt == IPPROTO_UDPLITE)
447 				UDPLITE_PROBE(receive, NULL, last, ip6, last, uh);
448 			else
449 				UDP_PROBE(receive, NULL, last, ip6, last, uh);
450 			if (udp6_append(last, m, off, fromsa) == 0)
451 				INP_RUNLOCK(last);
452 		} else
453 			INP_RUNLOCK(last);
454 		*mp = NULL;
455 		return (IPPROTO_DONE);
456 	}
457 	/*
458 	 * Locate pcb for datagram.
459 	 */
460 
461 	/*
462 	 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
463 	 */
464 	if ((m->m_flags & M_IP6_NEXTHOP) &&
465 	    (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
466 		struct sockaddr_in6 *next_hop6;
467 
468 		next_hop6 = (struct sockaddr_in6 *)(fwd_tag + 1);
469 
470 		/*
471 		 * Transparently forwarded. Pretend to be the destination.
472 		 * Already got one like this?
473 		 */
474 		inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
475 		    uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
476 		    INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif, m);
477 		if (!inp) {
478 			/*
479 			 * It's new.  Try to find the ambushing socket.
480 			 * Because we've rewritten the destination address,
481 			 * any hardware-generated hash is ignored.
482 			 */
483 			inp = in6_pcblookup(pcbinfo, &ip6->ip6_src,
484 			    uh->uh_sport, &next_hop6->sin6_addr,
485 			    next_hop6->sin6_port ? htons(next_hop6->sin6_port) :
486 			    uh->uh_dport, INPLOOKUP_WILDCARD |
487 			    INPLOOKUP_RLOCKPCB, m->m_pkthdr.rcvif);
488 		}
489 		/* Remove the tag from the packet. We don't need it anymore. */
490 		m_tag_delete(m, fwd_tag);
491 		m->m_flags &= ~M_IP6_NEXTHOP;
492 	} else
493 		inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_src,
494 		    uh->uh_sport, &ip6->ip6_dst, uh->uh_dport,
495 		    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
496 		    m->m_pkthdr.rcvif, m);
497 	if (inp == NULL) {
498 		if (V_udp_log_in_vain) {
499 			char ip6bufs[INET6_ADDRSTRLEN];
500 			char ip6bufd[INET6_ADDRSTRLEN];
501 
502 			log(LOG_INFO,
503 			    "Connection attempt to UDP [%s]:%d from [%s]:%d\n",
504 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
505 			    ntohs(uh->uh_dport),
506 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
507 			    ntohs(uh->uh_sport));
508 		}
509 		if (nxt == IPPROTO_UDPLITE)
510 			UDPLITE_PROBE(receive, NULL, NULL, ip6, NULL, uh);
511 		else
512 			UDP_PROBE(receive, NULL, NULL, ip6, NULL, uh);
513 		UDPSTAT_INC(udps_noport);
514 		if (m->m_flags & M_MCAST) {
515 			printf("UDP6: M_MCAST is set in a unicast packet.\n");
516 			UDPSTAT_INC(udps_noportmcast);
517 			goto badunlocked;
518 		}
519 		if (V_udp_blackhole)
520 			goto badunlocked;
521 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
522 		*mp = NULL;
523 		return (IPPROTO_DONE);
524 	}
525 	INP_RLOCK_ASSERT(inp);
526 	up = intoudpcb(inp);
527 	if (cscov_partial) {
528 		if (up->u_rxcslen == 0 || up->u_rxcslen > ulen) {
529 			INP_RUNLOCK(inp);
530 			m_freem(m);
531 			*mp = NULL;
532 			return (IPPROTO_DONE);
533 		}
534 	}
535 	if (nxt == IPPROTO_UDPLITE)
536 		UDPLITE_PROBE(receive, NULL, inp, ip6, inp, uh);
537 	else
538 		UDP_PROBE(receive, NULL, inp, ip6, inp, uh);
539 	if (udp6_append(inp, m, off, fromsa) == 0)
540 		INP_RUNLOCK(inp);
541 	*mp = NULL;
542 	return (IPPROTO_DONE);
543 
544 badunlocked:
545 	m_freem(m);
546 	*mp = NULL;
547 	return (IPPROTO_DONE);
548 }
549 
550 static void
551 udp6_common_ctlinput(int cmd, struct sockaddr *sa, void *d,
552     struct inpcbinfo *pcbinfo)
553 {
554 	struct udphdr uh;
555 	struct ip6_hdr *ip6;
556 	struct mbuf *m;
557 	int off = 0;
558 	struct ip6ctlparam *ip6cp = NULL;
559 	const struct sockaddr_in6 *sa6_src = NULL;
560 	void *cmdarg;
561 	struct inpcb *(*notify)(struct inpcb *, int) = udp_notify;
562 	struct udp_portonly {
563 		u_int16_t uh_sport;
564 		u_int16_t uh_dport;
565 	} *uhp;
566 
567 	if (sa->sa_family != AF_INET6 ||
568 	    sa->sa_len != sizeof(struct sockaddr_in6))
569 		return;
570 
571 	if ((unsigned)cmd >= PRC_NCMDS)
572 		return;
573 	if (PRC_IS_REDIRECT(cmd))
574 		notify = in6_rtchange, d = NULL;
575 	else if (cmd == PRC_HOSTDEAD)
576 		d = NULL;
577 	else if (inet6ctlerrmap[cmd] == 0)
578 		return;
579 
580 	/* if the parameter is from icmp6, decode it. */
581 	if (d != NULL) {
582 		ip6cp = (struct ip6ctlparam *)d;
583 		m = ip6cp->ip6c_m;
584 		ip6 = ip6cp->ip6c_ip6;
585 		off = ip6cp->ip6c_off;
586 		cmdarg = ip6cp->ip6c_cmdarg;
587 		sa6_src = ip6cp->ip6c_src;
588 	} else {
589 		m = NULL;
590 		ip6 = NULL;
591 		cmdarg = NULL;
592 		sa6_src = &sa6_any;
593 	}
594 
595 	if (ip6) {
596 		/*
597 		 * XXX: We assume that when IPV6 is non NULL,
598 		 * M and OFF are valid.
599 		 */
600 
601 		/* Check if we can safely examine src and dst ports. */
602 		if (m->m_pkthdr.len < off + sizeof(*uhp))
603 			return;
604 
605 		bzero(&uh, sizeof(uh));
606 		m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
607 
608 		if (!PRC_IS_REDIRECT(cmd)) {
609 			/* Check to see if its tunneled */
610 			struct inpcb *inp;
611 			inp = in6_pcblookup_mbuf(pcbinfo, &ip6->ip6_dst,
612 			    uh.uh_dport, &ip6->ip6_src, uh.uh_sport,
613 			    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB,
614 			    m->m_pkthdr.rcvif, m);
615 			if (inp != NULL) {
616 				struct udpcb *up;
617 
618 				up = intoudpcb(inp);
619 				if (up->u_icmp_func) {
620 					/* Yes it is. */
621 					INP_RUNLOCK(inp);
622 					(*up->u_icmp_func)(cmd, (struct sockaddr *)ip6cp->ip6c_src,
623 					      d, up->u_tun_ctx);
624 					return;
625 				} else {
626 					/* Can't find it. */
627 					INP_RUNLOCK(inp);
628 				}
629 			}
630 		}
631 		(void)in6_pcbnotify(pcbinfo, sa, uh.uh_dport,
632 		    (struct sockaddr *)ip6cp->ip6c_src, uh.uh_sport, cmd,
633 		    cmdarg, notify);
634 	} else
635 		(void)in6_pcbnotify(pcbinfo, sa, 0,
636 		    (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
637 }
638 
639 void
640 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
641 {
642 
643 	return (udp6_common_ctlinput(cmd, sa, d, &V_udbinfo));
644 }
645 
646 void
647 udplite6_ctlinput(int cmd, struct sockaddr *sa, void *d)
648 {
649 
650 	return (udp6_common_ctlinput(cmd, sa, d, &V_ulitecbinfo));
651 }
652 
653 static int
654 udp6_getcred(SYSCTL_HANDLER_ARGS)
655 {
656 	struct xucred xuc;
657 	struct sockaddr_in6 addrs[2];
658 	struct epoch_tracker et;
659 	struct inpcb *inp;
660 	int error;
661 
662 	error = priv_check(req->td, PRIV_NETINET_GETCRED);
663 	if (error)
664 		return (error);
665 
666 	if (req->newlen != sizeof(addrs))
667 		return (EINVAL);
668 	if (req->oldlen != sizeof(struct xucred))
669 		return (EINVAL);
670 	error = SYSCTL_IN(req, addrs, sizeof(addrs));
671 	if (error)
672 		return (error);
673 	if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
674 	    (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
675 		return (error);
676 	}
677 	NET_EPOCH_ENTER(et);
678 	inp = in6_pcblookup(&V_udbinfo, &addrs[1].sin6_addr,
679 	    addrs[1].sin6_port, &addrs[0].sin6_addr, addrs[0].sin6_port,
680 	    INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
681 	NET_EPOCH_EXIT(et);
682 	if (inp != NULL) {
683 		INP_RLOCK_ASSERT(inp);
684 		if (inp->inp_socket == NULL)
685 			error = ENOENT;
686 		if (error == 0)
687 			error = cr_canseesocket(req->td->td_ucred,
688 			    inp->inp_socket);
689 		if (error == 0)
690 			cru2x(inp->inp_cred, &xuc);
691 		INP_RUNLOCK(inp);
692 	} else
693 		error = ENOENT;
694 	if (error == 0)
695 		error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
696 	return (error);
697 }
698 
699 SYSCTL_PROC(_net_inet6_udp6, OID_AUTO, getcred,
700     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_MPSAFE,
701     0, 0, udp6_getcred, "S,xucred",
702     "Get the xucred of a UDP6 connection");
703 
704 static int
705 udp6_output(struct socket *so, int flags_arg, struct mbuf *m,
706     struct sockaddr *addr6, struct mbuf *control, struct thread *td)
707 {
708 	struct inpcb *inp;
709 	struct ip6_hdr *ip6;
710 	struct udphdr *udp6;
711 	struct in6_addr *laddr, *faddr, in6a;
712 	struct ip6_pktopts *optp, opt;
713 	struct sockaddr_in6 *sin6, tmp;
714 	struct epoch_tracker et;
715 	int cscov_partial, error, flags, hlen, scope_ambiguous;
716 	u_int32_t ulen, plen;
717 	uint16_t cscov;
718 	u_short fport;
719 	uint8_t nxt;
720 
721 	/* addr6 has been validated in udp6_send(). */
722 	sin6 = (struct sockaddr_in6 *)addr6;
723 
724 	/*
725 	 * In contrast to to IPv4 we do not validate the max. packet length
726 	 * here due to IPv6 Jumbograms (RFC2675).
727 	 */
728 
729 	scope_ambiguous = 0;
730 	if (sin6) {
731 		/* Protect *addr6 from overwrites. */
732 		tmp = *sin6;
733 		sin6 = &tmp;
734 
735 		/*
736 		 * Application should provide a proper zone ID or the use of
737 		 * default zone IDs should be enabled.  Unfortunately, some
738 		 * applications do not behave as it should, so we need a
739 		 * workaround.  Even if an appropriate ID is not determined,
740 		 * we'll see if we can determine the outgoing interface.  If we
741 		 * can, determine the zone ID based on the interface below.
742 		 */
743 		if (sin6->sin6_scope_id == 0 && !V_ip6_use_defzone)
744 			scope_ambiguous = 1;
745 		if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0) {
746 			if (control)
747 				m_freem(control);
748 			m_freem(m);
749 			return (error);
750 		}
751 	}
752 
753 	inp = sotoinpcb(so);
754 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
755 	/*
756 	 * In the following cases we want a write lock on the inp for either
757 	 * local operations or for possible route cache updates in the IPv6
758 	 * output path:
759 	 * - on connected sockets (sin6 is NULL) for route cache updates,
760 	 * - when we are not bound to an address and source port (it is
761 	 *   in6_pcbsetport() which will require the write lock).
762 	 *
763 	 * We check the inp fields before actually locking the inp, so
764 	 * here exists a race, and we may WLOCK the inp and end with already
765 	 * bound one by other thread. This is fine.
766 	 */
767 	if (sin6 == NULL || (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
768 	    inp->inp_lport == 0))
769 		INP_WLOCK(inp);
770 	else
771 		INP_RLOCK(inp);
772 
773 	nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
774 	    IPPROTO_UDP : IPPROTO_UDPLITE;
775 
776 #ifdef INET
777 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
778 		int hasv4addr;
779 
780 		if (sin6 == NULL)
781 			hasv4addr = (inp->inp_vflag & INP_IPV4);
782 		else
783 			hasv4addr = IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)
784 			    ? 1 : 0;
785 		if (hasv4addr) {
786 			struct pr_usrreqs *pru;
787 
788 			/*
789 			 * XXXRW: We release UDP-layer locks before calling
790 			 * udp_send() in order to avoid recursion.  However,
791 			 * this does mean there is a short window where inp's
792 			 * fields are unstable.  Could this lead to a
793 			 * potential race in which the factors causing us to
794 			 * select the UDPv4 output routine are invalidated?
795 			 */
796 			INP_UNLOCK(inp);
797 			if (sin6)
798 				in6_sin6_2_sin_in_sock((struct sockaddr *)sin6);
799 			pru = inetsw[ip_protox[nxt]].pr_usrreqs;
800 			/* addr will just be freed in sendit(). */
801 			return ((*pru->pru_send)(so, flags_arg | PRUS_IPV6, m,
802 			    (struct sockaddr *)sin6, control, td));
803 		}
804 	} else
805 #endif
806 	if (sin6 && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
807 		/*
808 		 * Given this is either an IPv6-only socket or no INET is
809 		 * supported we will fail the send if the given destination
810 		 * address is a v4mapped address.
811 		 *
812 		 * XXXGL: do we leak m and control?
813 		 */
814 		INP_UNLOCK(inp);
815 		return (EINVAL);
816 	}
817 
818 	if (control) {
819 		if ((error = ip6_setpktopts(control, &opt,
820 		    inp->in6p_outputopts, td->td_ucred, nxt)) != 0) {
821 			INP_UNLOCK(inp);
822 			ip6_clearpktopts(&opt, -1);
823 			if (control)
824 				m_freem(control);
825 			m_freem(m);
826 			return (error);
827 		}
828 		optp = &opt;
829 	} else
830 		optp = inp->in6p_outputopts;
831 
832 	NET_EPOCH_ENTER(et);
833 	if (sin6) {
834 		/*
835 		 * Since we saw no essential reason for calling in_pcbconnect,
836 		 * we get rid of such kind of logic, and call in6_selectsrc
837 		 * and in6_pcbsetport in order to fill in the local address
838 		 * and the local port.
839 		 */
840 		if (sin6->sin6_port == 0) {
841 			error = EADDRNOTAVAIL;
842 			goto release;
843 		}
844 
845 		if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
846 			/* how about ::ffff:0.0.0.0 case? */
847 			error = EISCONN;
848 			goto release;
849 		}
850 
851 		/*
852 		 * Given we handle the v4mapped case in the INET block above
853 		 * assert here that it must not happen anymore.
854 		 */
855 		KASSERT(!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr),
856 		    ("%s: sin6(%p)->sin6_addr is v4mapped which we "
857 		    "should have handled.", __func__, sin6));
858 
859 		/* This only requires read-locking. */
860 		error = in6_selectsrc_socket(sin6, optp, inp,
861 		    td->td_ucred, scope_ambiguous, &in6a, NULL);
862 		if (error)
863 			goto release;
864 		laddr = &in6a;
865 
866 		if (inp->inp_lport == 0) {
867 			struct inpcbinfo *pcbinfo;
868 
869 			INP_WLOCK_ASSERT(inp);
870 
871 			pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
872 			INP_HASH_WLOCK(pcbinfo);
873 			error = in6_pcbsetport(laddr, inp, td->td_ucred);
874 			INP_HASH_WUNLOCK(pcbinfo);
875 			if (error != 0) {
876 				/* Undo an address bind that may have occurred. */
877 				inp->in6p_laddr = in6addr_any;
878 				goto release;
879 			}
880 		}
881 		faddr = &sin6->sin6_addr;
882 		fport = sin6->sin6_port; /* allow 0 port */
883 
884 	} else {
885 		if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
886 			error = ENOTCONN;
887 			goto release;
888 		}
889 		laddr = &inp->in6p_laddr;
890 		faddr = &inp->in6p_faddr;
891 		fport = inp->inp_fport;
892 	}
893 
894 	ulen = m->m_pkthdr.len;
895 	plen = sizeof(struct udphdr) + ulen;
896 	hlen = sizeof(struct ip6_hdr);
897 
898 	/*
899 	 * Calculate data length and get a mbuf
900 	 * for UDP and IP6 headers.
901 	 */
902 	M_PREPEND(m, hlen + sizeof(struct udphdr), M_NOWAIT);
903 	if (m == NULL) {
904 		error = ENOBUFS;
905 		goto release;
906 	}
907 
908 	/*
909 	 * Stuff checksum and output datagram.
910 	 */
911 	cscov = cscov_partial = 0;
912 	udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
913 	udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
914 	udp6->uh_dport = fport;
915 	if (nxt == IPPROTO_UDPLITE) {
916 		struct udpcb *up;
917 
918 		up = intoudpcb(inp);
919 		cscov = up->u_txcslen;
920 		if (cscov >= plen)
921 			cscov = 0;
922 		udp6->uh_ulen = htons(cscov);
923 		/*
924 		 * For UDP-Lite, checksum coverage length of zero means
925 		 * the entire UDPLite packet is covered by the checksum.
926 		 */
927 		cscov_partial = (cscov == 0) ? 0 : 1;
928 	} else if (plen <= 0xffff)
929 		udp6->uh_ulen = htons((u_short)plen);
930 	else
931 		udp6->uh_ulen = 0;
932 	udp6->uh_sum = 0;
933 
934 	ip6 = mtod(m, struct ip6_hdr *);
935 	ip6->ip6_flow	= inp->inp_flow & IPV6_FLOWINFO_MASK;
936 	ip6->ip6_vfc	&= ~IPV6_VERSION_MASK;
937 	ip6->ip6_vfc	|= IPV6_VERSION;
938 	ip6->ip6_plen	= htons((u_short)plen);
939 	ip6->ip6_nxt	= nxt;
940 	ip6->ip6_hlim	= in6_selecthlim(inp, NULL);
941 	ip6->ip6_src	= *laddr;
942 	ip6->ip6_dst	= *faddr;
943 
944 #ifdef MAC
945 	mac_inpcb_create_mbuf(inp, m);
946 #endif
947 
948 	if (cscov_partial) {
949 		if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
950 		    sizeof(struct ip6_hdr), plen, cscov)) == 0)
951 			udp6->uh_sum = 0xffff;
952 	} else {
953 		udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
954 		m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
955 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
956 	}
957 
958 	flags = 0;
959 #if defined(ROUTE_MPATH) || defined(RSS)
960 	if (CALC_FLOWID_OUTBOUND_SENDTO) {
961 		uint32_t hash_type, hash_val;
962 		uint8_t pr;
963 
964 		pr = inp->inp_socket->so_proto->pr_protocol;
965 
966 		hash_val = fib6_calc_packet_hash(laddr, faddr,
967 		    inp->inp_lport, fport, pr, &hash_type);
968 		m->m_pkthdr.flowid = hash_val;
969 		M_HASHTYPE_SET(m, hash_type);
970 	}
971 	/* do not use inp flowid */
972 	flags |= IP_NODEFAULTFLOWID;
973 #endif
974 
975 	UDPSTAT_INC(udps_opackets);
976 	if (nxt == IPPROTO_UDPLITE)
977 		UDPLITE_PROBE(send, NULL, inp, ip6, inp, udp6);
978 	else
979 		UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
980 	error = ip6_output(m, optp,
981 	    INP_WLOCKED(inp) ? &inp->inp_route6 : NULL, flags,
982 	    inp->in6p_moptions, NULL, inp);
983 	INP_UNLOCK(inp);
984 	NET_EPOCH_EXIT(et);
985 
986 	if (control) {
987 		ip6_clearpktopts(&opt, -1);
988 		m_freem(control);
989 	}
990 	return (error);
991 
992 release:
993 	INP_UNLOCK(inp);
994 	NET_EPOCH_EXIT(et);
995 	if (control) {
996 		ip6_clearpktopts(&opt, -1);
997 		m_freem(control);
998 	}
999 	m_freem(m);
1000 
1001 	return (error);
1002 }
1003 
1004 static void
1005 udp6_abort(struct socket *so)
1006 {
1007 	struct inpcb *inp;
1008 	struct inpcbinfo *pcbinfo;
1009 
1010 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1011 	inp = sotoinpcb(so);
1012 	KASSERT(inp != NULL, ("udp6_abort: inp == NULL"));
1013 
1014 	INP_WLOCK(inp);
1015 #ifdef INET
1016 	if (inp->inp_vflag & INP_IPV4) {
1017 		struct pr_usrreqs *pru;
1018 		uint8_t nxt;
1019 
1020 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1021 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1022 		INP_WUNLOCK(inp);
1023 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1024 		(*pru->pru_abort)(so);
1025 		return;
1026 	}
1027 #endif
1028 
1029 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1030 		INP_HASH_WLOCK(pcbinfo);
1031 		in6_pcbdisconnect(inp);
1032 		inp->in6p_laddr = in6addr_any;
1033 		INP_HASH_WUNLOCK(pcbinfo);
1034 		soisdisconnected(so);
1035 	}
1036 	INP_WUNLOCK(inp);
1037 }
1038 
1039 static int
1040 udp6_attach(struct socket *so, int proto, struct thread *td)
1041 {
1042 	struct inpcb *inp;
1043 	struct inpcbinfo *pcbinfo;
1044 	int error;
1045 
1046 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1047 	inp = sotoinpcb(so);
1048 	KASSERT(inp == NULL, ("udp6_attach: inp != NULL"));
1049 
1050 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1051 		error = soreserve(so, udp_sendspace, udp_recvspace);
1052 		if (error)
1053 			return (error);
1054 	}
1055 	INP_INFO_WLOCK(pcbinfo);
1056 	error = in_pcballoc(so, pcbinfo);
1057 	if (error) {
1058 		INP_INFO_WUNLOCK(pcbinfo);
1059 		return (error);
1060 	}
1061 	inp = (struct inpcb *)so->so_pcb;
1062 	inp->inp_vflag |= INP_IPV6;
1063 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
1064 		inp->inp_vflag |= INP_IPV4;
1065 	inp->in6p_hops = -1;	/* use kernel default */
1066 	inp->in6p_cksum = -1;	/* just to be sure */
1067 	/*
1068 	 * XXX: ugly!!
1069 	 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1070 	 * because the socket may be bound to an IPv6 wildcard address,
1071 	 * which may match an IPv4-mapped IPv6 address.
1072 	 */
1073 	inp->inp_ip_ttl = V_ip_defttl;
1074 
1075 	error = udp_newudpcb(inp);
1076 	if (error) {
1077 		in_pcbdetach(inp);
1078 		in_pcbfree(inp);
1079 		INP_INFO_WUNLOCK(pcbinfo);
1080 		return (error);
1081 	}
1082 	INP_WUNLOCK(inp);
1083 	INP_INFO_WUNLOCK(pcbinfo);
1084 	return (0);
1085 }
1086 
1087 static int
1088 udp6_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1089 {
1090 	struct inpcb *inp;
1091 	struct inpcbinfo *pcbinfo;
1092 	int error;
1093 	u_char vflagsav;
1094 
1095 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1096 	inp = sotoinpcb(so);
1097 	KASSERT(inp != NULL, ("udp6_bind: inp == NULL"));
1098 
1099 	INP_WLOCK(inp);
1100 	INP_HASH_WLOCK(pcbinfo);
1101 	vflagsav = inp->inp_vflag;
1102 	inp->inp_vflag &= ~INP_IPV4;
1103 	inp->inp_vflag |= INP_IPV6;
1104 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1105 		struct sockaddr_in6 *sin6_p;
1106 
1107 		sin6_p = (struct sockaddr_in6 *)nam;
1108 
1109 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr))
1110 			inp->inp_vflag |= INP_IPV4;
1111 #ifdef INET
1112 		else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
1113 			struct sockaddr_in sin;
1114 
1115 			in6_sin6_2_sin(&sin, sin6_p);
1116 			inp->inp_vflag |= INP_IPV4;
1117 			inp->inp_vflag &= ~INP_IPV6;
1118 			error = in_pcbbind(inp, (struct sockaddr *)&sin,
1119 			    td->td_ucred);
1120 			goto out;
1121 		}
1122 #endif
1123 	}
1124 
1125 	error = in6_pcbbind(inp, nam, td->td_ucred);
1126 #ifdef INET
1127 out:
1128 #endif
1129 	if (error != 0)
1130 		inp->inp_vflag = vflagsav;
1131 	INP_HASH_WUNLOCK(pcbinfo);
1132 	INP_WUNLOCK(inp);
1133 	return (error);
1134 }
1135 
1136 static void
1137 udp6_close(struct socket *so)
1138 {
1139 	struct inpcb *inp;
1140 	struct inpcbinfo *pcbinfo;
1141 
1142 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1143 	inp = sotoinpcb(so);
1144 	KASSERT(inp != NULL, ("udp6_close: inp == NULL"));
1145 
1146 	INP_WLOCK(inp);
1147 #ifdef INET
1148 	if (inp->inp_vflag & INP_IPV4) {
1149 		struct pr_usrreqs *pru;
1150 		uint8_t nxt;
1151 
1152 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1153 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1154 		INP_WUNLOCK(inp);
1155 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1156 		(*pru->pru_disconnect)(so);
1157 		return;
1158 	}
1159 #endif
1160 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1161 		INP_HASH_WLOCK(pcbinfo);
1162 		in6_pcbdisconnect(inp);
1163 		inp->in6p_laddr = in6addr_any;
1164 		INP_HASH_WUNLOCK(pcbinfo);
1165 		soisdisconnected(so);
1166 	}
1167 	INP_WUNLOCK(inp);
1168 }
1169 
1170 static int
1171 udp6_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1172 {
1173 #ifdef INET
1174 	struct epoch_tracker et;
1175 #endif
1176 	struct inpcb *inp;
1177 	struct inpcbinfo *pcbinfo;
1178 	struct sockaddr_in6 *sin6;
1179 	int error;
1180 	u_char vflagsav;
1181 
1182 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1183 	inp = sotoinpcb(so);
1184 	sin6 = (struct sockaddr_in6 *)nam;
1185 	KASSERT(inp != NULL, ("udp6_connect: inp == NULL"));
1186 
1187 	/*
1188 	 * XXXRW: Need to clarify locking of v4/v6 flags.
1189 	 */
1190 	INP_WLOCK(inp);
1191 #ifdef INET
1192 	if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
1193 		struct sockaddr_in sin;
1194 
1195 		if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
1196 			error = EINVAL;
1197 			goto out;
1198 		}
1199 		if ((inp->inp_vflag & INP_IPV4) == 0) {
1200 			error = EAFNOSUPPORT;
1201 			goto out;
1202 		}
1203 		if (inp->inp_faddr.s_addr != INADDR_ANY) {
1204 			error = EISCONN;
1205 			goto out;
1206 		}
1207 		in6_sin6_2_sin(&sin, sin6);
1208 		error = prison_remote_ip4(td->td_ucred, &sin.sin_addr);
1209 		if (error != 0)
1210 			goto out;
1211 		vflagsav = inp->inp_vflag;
1212 		inp->inp_vflag |= INP_IPV4;
1213 		inp->inp_vflag &= ~INP_IPV6;
1214 		NET_EPOCH_ENTER(et);
1215 		INP_HASH_WLOCK(pcbinfo);
1216 		error = in_pcbconnect(inp, (struct sockaddr *)&sin,
1217 		    td->td_ucred);
1218 		INP_HASH_WUNLOCK(pcbinfo);
1219 		NET_EPOCH_EXIT(et);
1220 		/*
1221 		 * If connect succeeds, mark socket as connected. If
1222 		 * connect fails and socket is unbound, reset inp_vflag
1223 		 * field.
1224 		 */
1225 		if (error == 0)
1226 			soisconnected(so);
1227 		else if (inp->inp_laddr.s_addr == INADDR_ANY &&
1228 		    inp->inp_lport == 0)
1229 			inp->inp_vflag = vflagsav;
1230 		goto out;
1231 	} else {
1232 		if ((inp->inp_vflag & INP_IPV6) == 0) {
1233 			error = EAFNOSUPPORT;
1234 			goto out;
1235 		}
1236 	}
1237 #endif
1238 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1239 		error = EISCONN;
1240 		goto out;
1241 	}
1242 	error = prison_remote_ip6(td->td_ucred, &sin6->sin6_addr);
1243 	if (error != 0)
1244 		goto out;
1245 	vflagsav = inp->inp_vflag;
1246 	inp->inp_vflag &= ~INP_IPV4;
1247 	inp->inp_vflag |= INP_IPV6;
1248 	INP_HASH_WLOCK(pcbinfo);
1249 	error = in6_pcbconnect(inp, nam, td->td_ucred);
1250 	INP_HASH_WUNLOCK(pcbinfo);
1251 	/*
1252 	 * If connect succeeds, mark socket as connected. If
1253 	 * connect fails and socket is unbound, reset inp_vflag
1254 	 * field.
1255 	 */
1256 	if (error == 0)
1257 		soisconnected(so);
1258 	else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
1259 	    inp->inp_lport == 0)
1260 		inp->inp_vflag = vflagsav;
1261 out:
1262 	INP_WUNLOCK(inp);
1263 	return (error);
1264 }
1265 
1266 static void
1267 udp6_detach(struct socket *so)
1268 {
1269 	struct inpcb *inp;
1270 	struct inpcbinfo *pcbinfo;
1271 	struct udpcb *up;
1272 
1273 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1274 	inp = sotoinpcb(so);
1275 	KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
1276 
1277 	INP_INFO_WLOCK(pcbinfo);
1278 	INP_WLOCK(inp);
1279 	up = intoudpcb(inp);
1280 	KASSERT(up != NULL, ("%s: up == NULL", __func__));
1281 	in_pcbdetach(inp);
1282 	in_pcbfree(inp);
1283 	INP_INFO_WUNLOCK(pcbinfo);
1284 	udp_discardcb(up);
1285 }
1286 
1287 static int
1288 udp6_disconnect(struct socket *so)
1289 {
1290 	struct inpcb *inp;
1291 	struct inpcbinfo *pcbinfo;
1292 
1293 	pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1294 	inp = sotoinpcb(so);
1295 	KASSERT(inp != NULL, ("udp6_disconnect: inp == NULL"));
1296 
1297 	INP_WLOCK(inp);
1298 #ifdef INET
1299 	if (inp->inp_vflag & INP_IPV4) {
1300 		struct pr_usrreqs *pru;
1301 		uint8_t nxt;
1302 
1303 		nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
1304 		    IPPROTO_UDP : IPPROTO_UDPLITE;
1305 		INP_WUNLOCK(inp);
1306 		pru = inetsw[ip_protox[nxt]].pr_usrreqs;
1307 		(void)(*pru->pru_disconnect)(so);
1308 		return (0);
1309 	}
1310 #endif
1311 
1312 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1313 		INP_WUNLOCK(inp);
1314 		return (ENOTCONN);
1315 	}
1316 
1317 	INP_HASH_WLOCK(pcbinfo);
1318 	in6_pcbdisconnect(inp);
1319 	inp->in6p_laddr = in6addr_any;
1320 	INP_HASH_WUNLOCK(pcbinfo);
1321 	SOCK_LOCK(so);
1322 	so->so_state &= ~SS_ISCONNECTED;		/* XXX */
1323 	SOCK_UNLOCK(so);
1324 	INP_WUNLOCK(inp);
1325 	return (0);
1326 }
1327 
1328 static int
1329 udp6_send(struct socket *so, int flags, struct mbuf *m,
1330     struct sockaddr *addr, struct mbuf *control, struct thread *td)
1331 {
1332 	int error;
1333 
1334 	if (addr) {
1335 		if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1336 			error = EINVAL;
1337 			goto bad;
1338 		}
1339 		if (addr->sa_family != AF_INET6) {
1340 			error = EAFNOSUPPORT;
1341 			goto bad;
1342 		}
1343 	}
1344 
1345 	return (udp6_output(so, flags, m, addr, control, td));
1346 
1347 bad:
1348 	if (control)
1349 		m_freem(control);
1350 	m_freem(m);
1351 	return (error);
1352 }
1353 
1354 struct pr_usrreqs udp6_usrreqs = {
1355 	.pru_abort =		udp6_abort,
1356 	.pru_attach =		udp6_attach,
1357 	.pru_bind =		udp6_bind,
1358 	.pru_connect =		udp6_connect,
1359 	.pru_control =		in6_control,
1360 	.pru_detach =		udp6_detach,
1361 	.pru_disconnect =	udp6_disconnect,
1362 	.pru_peeraddr =		in6_mapped_peeraddr,
1363 	.pru_send =		udp6_send,
1364 	.pru_shutdown =		udp_shutdown,
1365 	.pru_sockaddr =		in6_mapped_sockaddr,
1366 	.pru_soreceive =	soreceive_dgram,
1367 	.pru_sosend =		sosend_dgram,
1368 	.pru_sosetlabel =	in_pcbsosetlabel,
1369 	.pru_close =		udp6_close
1370 };
1371