xref: /netbsd-src/sys/netinet6/udp6_usrreq.c (revision f4748aaa01faf324805f9747191535eb6600f82c)
1 /* $NetBSD: udp6_usrreq.c,v 1.154 2022/11/04 09:01:53 ozaki-r Exp $ */
2 /* $KAME: udp6_usrreq.c,v 1.86 2001/05/27 17:33:00 itojun Exp $ */
3 /* $KAME: udp6_output.c,v 1.43 2001/10/15 09:19:52 itojun Exp $ */
4 
5 /*
6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 1982, 1986, 1989, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  *
62  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
63  */
64 
65 #include <sys/cdefs.h>
66 __KERNEL_RCSID(0, "$NetBSD: udp6_usrreq.c,v 1.154 2022/11/04 09:01:53 ozaki-r Exp $");
67 
68 #ifdef _KERNEL_OPT
69 #include "opt_inet.h"
70 #include "opt_inet_csum.h"
71 #include "opt_ipsec.h"
72 #include "opt_net_mpsafe.h"
73 #endif
74 
75 #include <sys/param.h>
76 #include <sys/mbuf.h>
77 #include <sys/protosw.h>
78 #include <sys/socket.h>
79 #include <sys/socketvar.h>
80 #include <sys/systm.h>
81 #include <sys/proc.h>
82 #include <sys/syslog.h>
83 #include <sys/domain.h>
84 #include <sys/sysctl.h>
85 
86 #include <net/if.h>
87 #include <net/if_types.h>
88 
89 #include <netinet/in.h>
90 #include <netinet/in_var.h>
91 #include <netinet/in_systm.h>
92 #include <netinet/in_offload.h>
93 #include <netinet/ip.h>
94 #include <netinet/ip_var.h>
95 #include <netinet/in_pcb.h>
96 #include <netinet/udp.h>
97 #include <netinet/udp_var.h>
98 #include <netinet/udp_private.h>
99 
100 #include <netinet/ip6.h>
101 #include <netinet/icmp6.h>
102 #include <netinet6/ip6_var.h>
103 #include <netinet6/ip6_private.h>
104 #include <netinet6/in6_pcb.h>
105 #include <netinet6/udp6_var.h>
106 #include <netinet6/udp6_private.h>
107 #include <netinet6/ip6protosw.h>
108 #include <netinet6/scope6_var.h>
109 
110 #ifdef IPSEC
111 #include <netipsec/ipsec.h>
112 #include <netipsec/esp.h>
113 #ifdef INET6
114 #include <netipsec/ipsec6.h>
115 #endif
116 #endif
117 
118 #include "faith.h"
119 #if defined(NFAITH) && NFAITH > 0
120 #include <net/if_faith.h>
121 #endif
122 
123 /*
124  * UDP protocol implementation.
125  * Per RFC 768, August, 1980.
126  */
127 
128 extern struct inpcbtable udbtable;
129 
130 percpu_t *udp6stat_percpu;
131 
132 /* UDP on IP6 parameters */
133 static int udp6_sendspace = 9216;	/* really max datagram size */
134 static int udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
135 					/* 40 1K datagrams */
136 
137 static void udp6_notify(struct inpcb *, int);
138 static void sysctl_net_inet6_udp6_setup(struct sysctllog **);
139 #ifdef IPSEC
140 static int udp6_espinudp(struct mbuf **, int);
141 #endif
142 
143 #ifdef UDP_CSUM_COUNTERS
144 #include <sys/device.h>
145 struct evcnt udp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
146     NULL, "udp6", "hwcsum bad");
147 struct evcnt udp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
148     NULL, "udp6", "hwcsum ok");
149 struct evcnt udp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
150     NULL, "udp6", "hwcsum data");
151 struct evcnt udp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
152     NULL, "udp6", "swcsum");
153 
154 EVCNT_ATTACH_STATIC(udp6_hwcsum_bad);
155 EVCNT_ATTACH_STATIC(udp6_hwcsum_ok);
156 EVCNT_ATTACH_STATIC(udp6_hwcsum_data);
157 EVCNT_ATTACH_STATIC(udp6_swcsum);
158 
159 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
160 #else
161 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
162 #endif
163 
164 void
165 udp6_init(void)
166 {
167 	sysctl_net_inet6_udp6_setup(NULL);
168 	udp6stat_percpu = percpu_alloc(sizeof(uint64_t) * UDP6_NSTATS);
169 
170 	udp_init_common();
171 }
172 
173 /*
174  * Notify a udp user of an asynchronous error;
175  * just wake up so that he can collect error status.
176  */
177 static	void
178 udp6_notify(struct inpcb *inp, int errno)
179 {
180 	inp->inp_socket->so_error = errno;
181 	sorwakeup(inp->inp_socket);
182 	sowwakeup(inp->inp_socket);
183 }
184 
185 void *
186 udp6_ctlinput(int cmd, const struct sockaddr *sa, void *d)
187 {
188 	struct udphdr uh;
189 	struct ip6_hdr *ip6;
190 	const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa;
191 	struct mbuf *m;
192 	int off;
193 	void *cmdarg;
194 	struct ip6ctlparam *ip6cp = NULL;
195 	const struct sockaddr_in6 *sa6_src = NULL;
196 	void (*notify)(struct inpcb *, int) = udp6_notify;
197 	struct udp_portonly {
198 		u_int16_t uh_sport;
199 		u_int16_t uh_dport;
200 	} *uhp;
201 
202 	if (sa->sa_family != AF_INET6 ||
203 	    sa->sa_len != sizeof(struct sockaddr_in6))
204 		return NULL;
205 
206 	if ((unsigned)cmd >= PRC_NCMDS)
207 		return NULL;
208 	if (PRC_IS_REDIRECT(cmd))
209 		notify = in6pcb_rtchange, d = NULL;
210 	else if (cmd == PRC_HOSTDEAD)
211 		d = NULL;
212 	else if (cmd == PRC_MSGSIZE) {
213 		/* special code is present, see below */
214 		notify = in6pcb_rtchange;
215 	}
216 	else if (inet6ctlerrmap[cmd] == 0)
217 		return NULL;
218 
219 	/* if the parameter is from icmp6, decode it. */
220 	if (d != NULL) {
221 		ip6cp = (struct ip6ctlparam *)d;
222 		m = ip6cp->ip6c_m;
223 		ip6 = ip6cp->ip6c_ip6;
224 		off = ip6cp->ip6c_off;
225 		cmdarg = ip6cp->ip6c_cmdarg;
226 		sa6_src = ip6cp->ip6c_src;
227 	} else {
228 		m = NULL;
229 		ip6 = NULL;
230 		cmdarg = NULL;
231 		sa6_src = &sa6_any;
232 		off = 0;
233 	}
234 
235 	if (ip6) {
236 		/* check if we can safely examine src and dst ports */
237 		if (m->m_pkthdr.len < off + sizeof(*uhp)) {
238 			if (cmd == PRC_MSGSIZE)
239 				icmp6_mtudisc_update((struct ip6ctlparam *)d, 0);
240 			return NULL;
241 		}
242 
243 		memset(&uh, 0, sizeof(uh));
244 		m_copydata(m, off, sizeof(*uhp), (void *)&uh);
245 
246 		if (cmd == PRC_MSGSIZE) {
247 			int valid = 0;
248 
249 			/*
250 			 * Check to see if we have a valid UDP socket
251 			 * corresponding to the address in the ICMPv6 message
252 			 * payload.
253 			 */
254 			if (in6pcb_lookup(&udbtable, &sa6->sin6_addr,
255 			    uh.uh_dport, (const struct in6_addr *)&sa6_src->sin6_addr,
256 			    uh.uh_sport, 0, 0))
257 				valid++;
258 #if 0
259 			/*
260 			 * As the use of sendto(2) is fairly popular,
261 			 * we may want to allow non-connected pcb too.
262 			 * But it could be too weak against attacks...
263 			 * We should at least check if the local address (= s)
264 			 * is really ours.
265 			 */
266 			else if (in6pcb_lookup_bound(&udbtable, &sa6->sin6_addr,
267 			    uh.uh_dport, 0))
268 				valid++;
269 #endif
270 
271 			/*
272 			 * Depending on the value of "valid" and routing table
273 			 * size (mtudisc_{hi,lo}wat), we will:
274 			 * - recalculate the new MTU and create the
275 			 *   corresponding routing entry, or
276 			 * - ignore the MTU change notification.
277 			 */
278 			icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
279 
280 			/*
281 			 * regardless of if we called
282 			 * icmp6_mtudisc_update(), we need to call
283 			 * in6pcb_notify(), to notify path MTU change
284 			 * to the userland (RFC3542), because some
285 			 * unconnected sockets may share the same
286 			 * destination and want to know the path MTU.
287 			 */
288 		}
289 
290 		(void)in6pcb_notify(&udbtable, sa, uh.uh_dport,
291 		    sin6tocsa(sa6_src), uh.uh_sport, cmd, cmdarg,
292 		    notify);
293 	} else {
294 		(void)in6pcb_notify(&udbtable, sa, 0,
295 		    sin6tocsa(sa6_src), 0, cmd, cmdarg, notify);
296 	}
297 	return NULL;
298 }
299 
300 int
301 udp6_ctloutput(int op, struct socket *so, struct sockopt *sopt)
302 {
303 	int s;
304 	int error = 0;
305 	struct inpcb *inp;
306 	int family;
307 	int optval;
308 
309 	family = so->so_proto->pr_domain->dom_family;
310 
311 	s = splsoftnet();
312 	switch (family) {
313 #ifdef INET
314 	case PF_INET:
315 		if (sopt->sopt_level != IPPROTO_UDP) {
316 			error = ip_ctloutput(op, so, sopt);
317 			goto end;
318 		}
319 		break;
320 #endif
321 #ifdef INET6
322 	case PF_INET6:
323 		if (sopt->sopt_level != IPPROTO_UDP) {
324 			error = ip6_ctloutput(op, so, sopt);
325 			goto end;
326 		}
327 		break;
328 #endif
329 	default:
330 		error = EAFNOSUPPORT;
331 		goto end;
332 	}
333 
334 	switch (op) {
335 	case PRCO_SETOPT:
336 		inp = sotoinpcb(so);
337 
338 		switch (sopt->sopt_name) {
339 		case UDP_ENCAP:
340 			error = sockopt_getint(sopt, &optval);
341 			if (error)
342 				break;
343 
344 			switch(optval) {
345 			case 0:
346 				inp->inp_flags &= ~IN6P_ESPINUDP;
347 				break;
348 
349 			case UDP_ENCAP_ESPINUDP:
350 				inp->inp_flags |= IN6P_ESPINUDP;
351 				break;
352 
353 			default:
354 				error = EINVAL;
355 				break;
356 			}
357 			break;
358 
359 		default:
360 			error = ENOPROTOOPT;
361 			break;
362 		}
363 		break;
364 
365 	default:
366 		error = EINVAL;
367 		break;
368 	}
369 
370 end:
371 	splx(s);
372 	return error;
373 }
374 
375 static void
376 udp6_sendup(struct mbuf *m, int off /* offset of data portion */,
377     struct sockaddr *src, struct socket *so)
378 {
379 	struct mbuf *opts = NULL;
380 	struct mbuf *n;
381 	struct inpcb *inp;
382 
383 	KASSERT(so != NULL);
384 	KASSERT(so->so_proto->pr_domain->dom_family == AF_INET6);
385 	inp = sotoinpcb(so);
386 	KASSERT(inp != NULL);
387 
388 #if defined(IPSEC)
389 	if (ipsec_used && ipsec_in_reject(m, inp)) {
390 		if ((n = m_copypacket(m, M_DONTWAIT)) != NULL)
391 			icmp6_error(n, ICMP6_DST_UNREACH,
392 			    ICMP6_DST_UNREACH_ADMIN, 0);
393 		return;
394 	}
395 #endif
396 
397 	if ((n = m_copypacket(m, M_DONTWAIT)) != NULL) {
398 		if (inp->inp_flags & IN6P_CONTROLOPTS ||
399 		    SOOPT_TIMESTAMP(inp->inp_socket->so_options)) {
400 			struct ip6_hdr *ip6 = mtod(n, struct ip6_hdr *);
401 			ip6_savecontrol(inp, &opts, ip6, n);
402 		}
403 
404 		m_adj(n, off);
405 		if (sbappendaddr(&so->so_rcv, src, n, opts) == 0) {
406 			m_freem(n);
407 			if (opts)
408 				m_freem(opts);
409 			UDP6_STATINC(UDP6_STAT_FULLSOCK);
410 			soroverflow(so);
411 		} else
412 			sorwakeup(so);
413 	}
414 }
415 
416 int
417 udp6_realinput(int af, struct sockaddr_in6 *src, struct sockaddr_in6 *dst,
418     struct mbuf **mp, int off)
419 {
420 	u_int16_t sport, dport;
421 	int rcvcnt;
422 	struct in6_addr src6, *dst6;
423 	const struct in_addr *dst4;
424 	struct inpcb *inp;
425 	struct mbuf *m = *mp;
426 
427 	rcvcnt = 0;
428 	off += sizeof(struct udphdr);	/* now, offset of payload */
429 
430 	if (af != AF_INET && af != AF_INET6)
431 		goto bad;
432 	if (src->sin6_family != AF_INET6 || dst->sin6_family != AF_INET6)
433 		goto bad;
434 
435 	src6 = src->sin6_addr;
436 	if (sa6_recoverscope(src) != 0) {
437 		/* XXX: should be impossible. */
438 		goto bad;
439 	}
440 	sport = src->sin6_port;
441 
442 	dport = dst->sin6_port;
443 	dst4 = (struct in_addr *)&dst->sin6_addr.s6_addr[12];
444 	dst6 = &dst->sin6_addr;
445 
446 	if (IN6_IS_ADDR_MULTICAST(dst6) ||
447 	    (af == AF_INET && IN_MULTICAST(dst4->s_addr))) {
448 		/*
449 		 * Deliver a multicast or broadcast datagram to *all* sockets
450 		 * for which the local and remote addresses and ports match
451 		 * those of the incoming datagram.  This allows more than
452 		 * one process to receive multi/broadcasts on the same port.
453 		 * (This really ought to be done for unicast datagrams as
454 		 * well, but that would cause problems with existing
455 		 * applications that open both address-specific sockets and
456 		 * a wildcard socket listening to the same port -- they would
457 		 * end up receiving duplicates of every unicast datagram.
458 		 * Those applications open the multiple sockets to overcome an
459 		 * inadequacy of the UDP socket interface, but for backwards
460 		 * compatibility we avoid the problem here rather than
461 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
462 		 */
463 
464 		/*
465 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
466 		 * we need udpiphdr for IPsec processing so we do that later.
467 		 */
468 		/*
469 		 * Locate pcb(s) for datagram.
470 		 */
471 		TAILQ_FOREACH(inp, &udbtable.inpt_queue, inp_queue) {
472 			if (inp->inp_af != AF_INET6)
473 				continue;
474 
475 			if (inp->inp_lport != dport)
476 				continue;
477 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p_laddr(inp))) {
478 				if (!IN6_ARE_ADDR_EQUAL(&in6p_laddr(inp),
479 				    dst6))
480 					continue;
481 			} else {
482 				if (IN6_IS_ADDR_V4MAPPED(dst6) &&
483 				    (inp->inp_flags & IN6P_IPV6_V6ONLY))
484 					continue;
485 			}
486 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p_faddr(inp))) {
487 				if (!IN6_ARE_ADDR_EQUAL(&in6p_faddr(inp),
488 				    &src6) || inp->inp_fport != sport)
489 					continue;
490 			} else {
491 				if (IN6_IS_ADDR_V4MAPPED(&src6) &&
492 				    (inp->inp_flags & IN6P_IPV6_V6ONLY))
493 					continue;
494 			}
495 
496 			udp6_sendup(m, off, sin6tosa(src), inp->inp_socket);
497 			rcvcnt++;
498 
499 			/*
500 			 * Don't look for additional matches if this one does
501 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
502 			 * socket options set.  This heuristic avoids searching
503 			 * through all pcbs in the common case of a non-shared
504 			 * port.  It assumes that an application will never
505 			 * clear these options after setting them.
506 			 */
507 			if ((inp->inp_socket->so_options &
508 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
509 				break;
510 		}
511 	} else {
512 		/*
513 		 * Locate pcb for datagram.
514 		 */
515 		inp = in6pcb_lookup(&udbtable, &src6, sport, dst6,
516 					     dport, 0, 0);
517 		if (inp == NULL) {
518 			UDP_STATINC(UDP_STAT_PCBHASHMISS);
519 			inp = in6pcb_lookup_bound(&udbtable, dst6, dport, 0);
520 			if (inp == NULL)
521 				return rcvcnt;
522 		}
523 
524 #ifdef IPSEC
525 		/* Handle ESP over UDP */
526 		if (inp->inp_flags & IN6P_ESPINUDP) {
527 			switch (udp6_espinudp(mp, off)) {
528 			case -1: /* Error, m was freed */
529 				rcvcnt = -1;
530 				goto bad;
531 
532 			case 1: /* ESP over UDP */
533 				rcvcnt++;
534 				goto bad;
535 
536 			case 0: /* plain UDP */
537 			default: /* Unexpected */
538 				/*
539 				 * Normal UDP processing will take place,
540 				 * m may have changed.
541 				 */
542 				m = *mp;
543 				break;
544 			}
545 		}
546 #endif
547 
548 		if (inp->inp_overudp_cb != NULL) {
549 			int ret;
550 			ret = inp->inp_overudp_cb(mp, off, inp->inp_socket,
551 			    sin6tosa(src), inp->inp_overudp_arg);
552 			switch (ret) {
553 			case -1: /* Error, m was freed */
554 				rcvcnt = -1;
555 				goto bad;
556 
557 			case 1: /* Foo over UDP */
558 				KASSERT(*mp == NULL);
559 				rcvcnt++;
560 				goto bad;
561 
562 			case 0: /* plain UDP */
563 			default: /* Unexpected */
564 				/*
565 				 * Normal UDP processing will take place,
566 				 * m may have changed.
567 				 */
568 				break;
569 			}
570 		}
571 
572 		udp6_sendup(m, off, sin6tosa(src), inp->inp_socket);
573 		rcvcnt++;
574 	}
575 
576 bad:
577 	return rcvcnt;
578 }
579 
580 int
581 udp6_input_checksum(struct mbuf *m, const struct udphdr *uh, int off, int len)
582 {
583 
584 	/*
585 	 * XXX it's better to record and check if this mbuf is
586 	 * already checked.
587 	 */
588 
589 	if (__predict_false((m->m_flags & M_LOOP) && !udp_do_loopback_cksum)) {
590 		goto good;
591 	}
592 	if (uh->uh_sum == 0) {
593 		UDP6_STATINC(UDP6_STAT_NOSUM);
594 		goto bad;
595 	}
596 
597 	switch (m->m_pkthdr.csum_flags &
598 	    ((m_get_rcvif_NOMPSAFE(m)->if_csum_flags_rx & M_CSUM_UDPv6) |
599 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
600 	case M_CSUM_UDPv6|M_CSUM_TCP_UDP_BAD:
601 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_bad);
602 		UDP6_STATINC(UDP6_STAT_BADSUM);
603 		goto bad;
604 
605 #if 0 /* notyet */
606 	case M_CSUM_UDPv6|M_CSUM_DATA:
607 #endif
608 
609 	case M_CSUM_UDPv6:
610 		/* Checksum was okay. */
611 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_ok);
612 		break;
613 
614 	default:
615 		/*
616 		 * Need to compute it ourselves.  Maybe skip checksum
617 		 * on loopback interfaces.
618 		 */
619 		UDP_CSUM_COUNTER_INCR(&udp6_swcsum);
620 		if (in6_cksum(m, IPPROTO_UDP, off, len) != 0) {
621 			UDP6_STATINC(UDP6_STAT_BADSUM);
622 			goto bad;
623 		}
624 	}
625 
626 good:
627 	return 0;
628 bad:
629 	return -1;
630 }
631 
632 int
633 udp6_input(struct mbuf **mp, int *offp, int proto)
634 {
635 	struct mbuf *m = *mp;
636 	int off = *offp;
637 	struct sockaddr_in6 src, dst;
638 	struct ip6_hdr *ip6;
639 	struct udphdr *uh;
640 	u_int32_t plen, ulen;
641 
642 	ip6 = mtod(m, struct ip6_hdr *);
643 
644 #if defined(NFAITH) && 0 < NFAITH
645 	if (faithprefix(&ip6->ip6_dst)) {
646 		/* send icmp6 host unreach? */
647 		m_freem(m);
648 		return IPPROTO_DONE;
649 	}
650 #endif
651 
652 	UDP6_STATINC(UDP6_STAT_IPACKETS);
653 
654 	/* Check for jumbogram is done in ip6_input. We can trust pkthdr.len. */
655 	plen = m->m_pkthdr.len - off;
656 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
657 	if (uh == NULL) {
658 		IP6_STATINC(IP6_STAT_TOOSHORT);
659 		return IPPROTO_DONE;
660 	}
661 
662 	/*
663 	 * Enforce alignment requirements that are violated in
664 	 * some cases, see kern/50766 for details.
665 	 */
666 	if (ACCESSIBLE_POINTER(uh, struct udphdr) == 0) {
667 		m = m_copyup(m, off + sizeof(struct udphdr), 0);
668 		if (m == NULL) {
669 			IP6_STATINC(IP6_STAT_TOOSHORT);
670 			return IPPROTO_DONE;
671 		}
672 		ip6 = mtod(m, struct ip6_hdr *);
673 		uh = (struct udphdr *)(mtod(m, char *) + off);
674 	}
675 	KASSERT(ACCESSIBLE_POINTER(uh, struct udphdr));
676 	ulen = ntohs((u_short)uh->uh_ulen);
677 
678 	/*
679 	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
680 	 * iff payload length > 0xffff.
681 	 */
682 	if (ulen == 0 && plen > 0xffff)
683 		ulen = plen;
684 
685 	if (plen != ulen) {
686 		UDP6_STATINC(UDP6_STAT_BADLEN);
687 		goto bad;
688 	}
689 
690 	/* destination port of 0 is illegal, based on RFC768. */
691 	if (uh->uh_dport == 0)
692 		goto bad;
693 
694 	/*
695 	 * Checksum extended UDP header and data.  Maybe skip checksum
696 	 * on loopback interfaces.
697 	 */
698 	if (udp6_input_checksum(m, uh, off, ulen))
699 		goto bad;
700 
701 	/*
702 	 * Construct source and dst sockaddrs.
703 	 */
704 	memset(&src, 0, sizeof(src));
705 	src.sin6_family = AF_INET6;
706 	src.sin6_len = sizeof(struct sockaddr_in6);
707 	src.sin6_addr = ip6->ip6_src;
708 	src.sin6_port = uh->uh_sport;
709 	memset(&dst, 0, sizeof(dst));
710 	dst.sin6_family = AF_INET6;
711 	dst.sin6_len = sizeof(struct sockaddr_in6);
712 	dst.sin6_addr = ip6->ip6_dst;
713 	dst.sin6_port = uh->uh_dport;
714 
715 	if (udp6_realinput(AF_INET6, &src, &dst, &m, off) == 0) {
716 		if (m->m_flags & M_MCAST) {
717 			UDP6_STATINC(UDP6_STAT_NOPORTMCAST);
718 			goto bad;
719 		}
720 		UDP6_STATINC(UDP6_STAT_NOPORT);
721 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
722 		m = NULL;
723 	}
724 
725 bad:
726 	if (m)
727 		m_freem(m);
728 	return IPPROTO_DONE;
729 }
730 
731 int
732 udp6_output(struct inpcb * const inp, struct mbuf *m,
733     struct sockaddr_in6 * const addr6, struct mbuf * const control,
734     struct lwp * const l)
735 {
736 	u_int32_t ulen = m->m_pkthdr.len;
737 	u_int32_t plen = sizeof(struct udphdr) + ulen;
738 	struct ip6_hdr *ip6;
739 	struct udphdr *udp6;
740 	struct in6_addr _laddr, *laddr, *faddr;
741 	struct in6_addr laddr_mapped; /* XXX ugly */
742 	struct sockaddr_in6 *sin6 = NULL;
743 	struct ifnet *oifp = NULL;
744 	int scope_ambiguous = 0;
745 	u_int16_t fport;
746 	int error = 0;
747 	struct ip6_pktopts *optp = NULL;
748 	struct ip6_pktopts opt;
749 	int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
750 #ifdef INET
751 	struct ip *ip;
752 	struct udpiphdr *ui;
753 	int flags = 0;
754 #endif
755 	struct sockaddr_in6 tmp;
756 
757 	if (addr6) {
758 		sin6 = addr6;
759 		if (sin6->sin6_len != sizeof(*sin6)) {
760 			error = EINVAL;
761 			goto release;
762 		}
763 		if (sin6->sin6_family != AF_INET6) {
764 			error = EAFNOSUPPORT;
765 			goto release;
766 		}
767 
768 		/* protect *sin6 from overwrites */
769 		tmp = *sin6;
770 		sin6 = &tmp;
771 
772 		/*
773 		 * Application should provide a proper zone ID or the use of
774 		 * default zone IDs should be enabled.  Unfortunately, some
775 		 * applications do not behave as it should, so we need a
776 		 * workaround.  Even if an appropriate ID is not determined,
777 		 * we'll see if we can determine the outgoing interface.  If we
778 		 * can, determine the zone ID based on the interface below.
779 		 */
780 		if (sin6->sin6_scope_id == 0 && !ip6_use_defzone)
781 			scope_ambiguous = 1;
782 		if ((error = sa6_embedscope(sin6, ip6_use_defzone)) != 0)
783 			goto release;
784 	}
785 
786 	if (control) {
787 		if (__predict_false(l == NULL)) {
788 			panic("%s: control but no lwp", __func__);
789 		}
790 		if ((error = ip6_setpktopts(control, &opt,
791 		    in6p_outputopts(inp), l->l_cred, IPPROTO_UDP)) != 0)
792 			goto release;
793 		optp = &opt;
794 	} else
795 		optp = in6p_outputopts(inp);
796 
797 
798 	if (sin6) {
799 		/*
800 		 * Slightly different than v4 version in that we call
801 		 * in6_selectsrc and in6pcb_set_port to fill in the local
802 		 * address and port rather than inpcb_connect. inpcb_connect
803 		 * sets inp_faddr which causes EISCONN below to be hit on
804 		 * subsequent sendto.
805 		 */
806 		if (sin6->sin6_port == 0) {
807 			error = EADDRNOTAVAIL;
808 			goto release;
809 		}
810 
811 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p_faddr(inp))) {
812 			/* how about ::ffff:0.0.0.0 case? */
813 			error = EISCONN;
814 			goto release;
815 		}
816 
817 		faddr = &sin6->sin6_addr;
818 		fport = sin6->sin6_port; /* allow 0 port */
819 
820 		if (IN6_IS_ADDR_V4MAPPED(faddr)) {
821 			if ((inp->inp_flags & IN6P_IPV6_V6ONLY)) {
822 				/*
823 				 * I believe we should explicitly discard the
824 				 * packet when mapped addresses are disabled,
825 				 * rather than send the packet as an IPv6 one.
826 				 * If we chose the latter approach, the packet
827 				 * might be sent out on the wire based on the
828 				 * default route, the situation which we'd
829 				 * probably want to avoid.
830 				 * (20010421 jinmei@kame.net)
831 				 */
832 				error = EINVAL;
833 				goto release;
834 			}
835 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p_laddr(inp)) &&
836 			    !IN6_IS_ADDR_V4MAPPED(&in6p_laddr(inp))) {
837 				/*
838 				 * when remote addr is an IPv4-mapped address,
839 				 * local addr should not be an IPv6 address,
840 				 * since you cannot determine how to map IPv6
841 				 * source address to IPv4.
842 				 */
843 				error = EINVAL;
844 				goto release;
845 			}
846 
847 			af = AF_INET;
848 		}
849 
850 		if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
851 			struct psref psref;
852 			int bound = curlwp_bind();
853 
854 			error = in6_selectsrc(sin6, optp,
855 			    in6p_moptions(inp),
856 			    &inp->inp_route,
857 			    &in6p_laddr(inp), &oifp, &psref, &_laddr);
858 			if (error)
859 				laddr = NULL;
860 			else
861 				laddr = &_laddr;
862 			if (oifp && scope_ambiguous &&
863 			    (error = in6_setscope(&sin6->sin6_addr,
864 			    oifp, NULL))) {
865 				if_put(oifp, &psref);
866 				curlwp_bindx(bound);
867 				goto release;
868 			}
869 			if_put(oifp, &psref);
870 			curlwp_bindx(bound);
871 		} else {
872 			/*
873 			 * XXX: freebsd[34] does not have in_selectsrc, but
874 			 * we can omit the whole part because freebsd4 calls
875 			 * udp_output() directly in this case, and thus we'll
876 			 * never see this path.
877 			 */
878 			if (IN6_IS_ADDR_UNSPECIFIED(&in6p_laddr(inp))) {
879 				struct sockaddr_in sin_dst;
880 				struct in_addr ina;
881 				struct in_ifaddr *ia4;
882 				struct psref _psref;
883 				int bound;
884 
885 				memcpy(&ina, &faddr->s6_addr[12], sizeof(ina));
886 				sockaddr_in_init(&sin_dst, &ina, 0);
887 				bound = curlwp_bind();
888 				ia4 = in_selectsrc(&sin_dst, &inp->inp_route,
889 				    inp->inp_socket->so_options, NULL,
890 				    &error, &_psref);
891 				if (ia4 == NULL) {
892 					curlwp_bindx(bound);
893 					if (error == 0)
894 						error = EADDRNOTAVAIL;
895 					goto release;
896 				}
897 				memset(&laddr_mapped, 0, sizeof(laddr_mapped));
898 				laddr_mapped.s6_addr16[5] = 0xffff; /* ugly */
899 				memcpy(&laddr_mapped.s6_addr[12],
900 				      &IA_SIN(ia4)->sin_addr,
901 				      sizeof(IA_SIN(ia4)->sin_addr));
902 				ia4_release(ia4, &_psref);
903 				curlwp_bindx(bound);
904 				laddr = &laddr_mapped;
905 			} else
906 			{
907 				laddr = &in6p_laddr(inp);	/* XXX */
908 			}
909 		}
910 		if (laddr == NULL) {
911 			if (error == 0)
912 				error = EADDRNOTAVAIL;
913 			goto release;
914 		}
915 		if (inp->inp_lport == 0) {
916 			/*
917 			 * Craft a sockaddr_in6 for the local endpoint. Use the
918 			 * "any" as a base, set the address, and recover the
919 			 * scope.
920 			 */
921 			struct sockaddr_in6 lsin6 =
922 			    *((const struct sockaddr_in6 *)inp->inp_socket->so_proto->pr_domain->dom_sa_any);
923 			lsin6.sin6_addr = *laddr;
924 			error = sa6_recoverscope(&lsin6);
925 			if (error)
926 				goto release;
927 
928 			error = in6pcb_set_port(&lsin6, inp, l);
929 
930 			if (error) {
931 				in6p_laddr(inp) = in6addr_any;
932 				goto release;
933 			}
934 		}
935 	} else {
936 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p_faddr(inp))) {
937 			error = ENOTCONN;
938 			goto release;
939 		}
940 		if (IN6_IS_ADDR_V4MAPPED(&in6p_faddr(inp))) {
941 			if ((inp->inp_flags & IN6P_IPV6_V6ONLY))
942 			{
943 				/*
944 				 * XXX: this case would happen when the
945 				 * application sets the V6ONLY flag after
946 				 * connecting the foreign address.
947 				 * Such applications should be fixed,
948 				 * so we bark here.
949 				 */
950 				log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
951 				    "option was set for a connected socket\n");
952 				error = EINVAL;
953 				goto release;
954 			} else
955 				af = AF_INET;
956 		}
957 		laddr = &in6p_laddr(inp);
958 		faddr = &in6p_faddr(inp);
959 		fport = inp->inp_fport;
960 	}
961 
962 	if (af == AF_INET)
963 		hlen = sizeof(struct ip);
964 
965 	/*
966 	 * Calculate data length and get a mbuf
967 	 * for UDP and IP6 headers.
968 	 */
969 	M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
970 	if (m == NULL) {
971 		error = ENOBUFS;
972 		goto release;
973 	}
974 
975 	/*
976 	 * Stuff checksum and output datagram.
977 	 */
978 	udp6 = (struct udphdr *)(mtod(m, char *) + hlen);
979 	udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
980 	udp6->uh_dport = fport;
981 	if (plen <= 0xffff)
982 		udp6->uh_ulen = htons((u_int16_t)plen);
983 	else
984 		udp6->uh_ulen = 0;
985 	udp6->uh_sum = 0;
986 
987 	switch (af) {
988 	case AF_INET6:
989 		ip6 = mtod(m, struct ip6_hdr *);
990 		ip6->ip6_flow	= in6p_flowinfo(inp) & IPV6_FLOWINFO_MASK;
991 		ip6->ip6_vfc 	&= ~IPV6_VERSION_MASK;
992 		ip6->ip6_vfc 	|= IPV6_VERSION;
993 #if 0		/* ip6_plen will be filled in ip6_output. */
994 		ip6->ip6_plen	= htons((u_int16_t)plen);
995 #endif
996 		ip6->ip6_nxt	= IPPROTO_UDP;
997 		ip6->ip6_hlim	= in6pcb_selecthlim_rt(inp);
998 		ip6->ip6_src	= *laddr;
999 		ip6->ip6_dst	= *faddr;
1000 
1001 		udp6->uh_sum = in6_cksum_phdr(laddr, faddr,
1002 		    htonl(plen), htonl(IPPROTO_UDP));
1003 		m->m_pkthdr.csum_flags = M_CSUM_UDPv6;
1004 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1005 
1006 		UDP6_STATINC(UDP6_STAT_OPACKETS);
1007 		error = ip6_output(m, optp, &inp->inp_route, 0,
1008 		    in6p_moptions(inp), inp, NULL);
1009 		break;
1010 	case AF_INET:
1011 #ifdef INET
1012 		/* can't transmit jumbogram over IPv4 */
1013 		if (plen > 0xffff) {
1014 			error = EMSGSIZE;
1015 			goto release;
1016 		}
1017 
1018 		ip = mtod(m, struct ip *);
1019 		ui = (struct udpiphdr *)ip;
1020 		memset(ui->ui_x1, 0, sizeof(ui->ui_x1));
1021 		ui->ui_pr = IPPROTO_UDP;
1022 		ui->ui_len = htons(plen);
1023 		memcpy(&ui->ui_src, &laddr->s6_addr[12], sizeof(ui->ui_src));
1024 		ui->ui_ulen = ui->ui_len;
1025 
1026 		flags = (inp->inp_socket->so_options &
1027 			 (SO_DONTROUTE | SO_BROADCAST));
1028 		memcpy(&ui->ui_dst, &faddr->s6_addr[12], sizeof(ui->ui_dst));
1029 
1030 		udp6->uh_sum = in_cksum(m, hlen + plen);
1031 		if (udp6->uh_sum == 0)
1032 			udp6->uh_sum = 0xffff;
1033 
1034 		ip->ip_len = htons(hlen + plen);
1035 		ip->ip_ttl = in6pcb_selecthlim(inp, NULL); /* XXX */
1036 		ip->ip_tos = 0;	/* XXX */
1037 
1038 		UDP_STATINC(UDP_STAT_OPACKETS);
1039 		error = ip_output(m, NULL, &inp->inp_route, flags /* XXX */,
1040 		    inp->inp_moptions, NULL);
1041 		break;
1042 #else
1043 		error = EAFNOSUPPORT;
1044 		goto release;
1045 #endif
1046 	}
1047 	goto releaseopt;
1048 
1049 release:
1050 	m_freem(m);
1051 
1052 releaseopt:
1053 	if (control) {
1054 		if (optp == &opt)
1055 			ip6_clearpktopts(&opt, -1);
1056 		m_freem(control);
1057 	}
1058 	return (error);
1059 }
1060 
1061 static int
1062 udp6_attach(struct socket *so, int proto)
1063 {
1064 	struct inpcb *inp;
1065 	int s, error;
1066 
1067 	KASSERT(sotoinpcb(so) == NULL);
1068 	sosetlock(so);
1069 
1070 	error = soreserve(so, udp6_sendspace, udp6_recvspace);
1071 	if (error) {
1072 		return error;
1073 	}
1074 
1075 	/*
1076 	 * MAPPED_ADDR implementation spec:
1077 	 *  Always attach for IPv6, and only when necessary for IPv4.
1078 	 */
1079 	s = splsoftnet();
1080 	error = inpcb_create(so, &udbtable);
1081 	splx(s);
1082 	if (error) {
1083 		return error;
1084 	}
1085 
1086 	inp = sotoinpcb(so);
1087 	in6p_cksum(inp) = -1;	/* just to be sure */
1088 
1089 	KASSERT(solocked(so));
1090 	return 0;
1091 }
1092 
1093 static void
1094 udp6_detach(struct socket *so)
1095 {
1096 	struct inpcb *inp = sotoinpcb(so);
1097 	int s;
1098 
1099 	KASSERT(solocked(so));
1100 	KASSERT(inp != NULL);
1101 
1102 	s = splsoftnet();
1103 	inpcb_destroy(inp);
1104 	splx(s);
1105 }
1106 
1107 static int
1108 udp6_accept(struct socket *so, struct sockaddr *nam)
1109 {
1110 	KASSERT(solocked(so));
1111 
1112 	return EOPNOTSUPP;
1113 }
1114 
1115 static int
1116 udp6_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
1117 {
1118 	struct inpcb *inp = sotoinpcb(so);
1119 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
1120 	int error = 0;
1121 	int s;
1122 
1123 	KASSERT(solocked(so));
1124 	KASSERT(inp != NULL);
1125 
1126 	s = splsoftnet();
1127 	error = in6pcb_bind(inp, sin6, l);
1128 	splx(s);
1129 	return error;
1130 }
1131 
1132 static int
1133 udp6_listen(struct socket *so, struct lwp *l)
1134 {
1135 	KASSERT(solocked(so));
1136 
1137 	return EOPNOTSUPP;
1138 }
1139 
1140 static int
1141 udp6_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
1142 {
1143 	struct inpcb *inp = sotoinpcb(so);
1144 	int error = 0;
1145 	int s;
1146 
1147 	KASSERT(solocked(so));
1148 	KASSERT(inp != NULL);
1149 
1150 	if (!IN6_IS_ADDR_UNSPECIFIED(&in6p_faddr(inp)))
1151 		return EISCONN;
1152 	s = splsoftnet();
1153 	error = in6pcb_connect(inp, (struct sockaddr_in6 *)nam, l);
1154 	splx(s);
1155 	if (error == 0)
1156 		soisconnected(so);
1157 
1158 	return error;
1159 }
1160 
1161 static int
1162 udp6_connect2(struct socket *so, struct socket *so2)
1163 {
1164 	KASSERT(solocked(so));
1165 
1166 	return EOPNOTSUPP;
1167 }
1168 
1169 static int
1170 udp6_disconnect(struct socket *so)
1171 {
1172 	struct inpcb *inp = sotoinpcb(so);
1173 	int s;
1174 
1175 	KASSERT(solocked(so));
1176 	KASSERT(inp != NULL);
1177 
1178 	if (IN6_IS_ADDR_UNSPECIFIED(&in6p_faddr(inp)))
1179 		return ENOTCONN;
1180 
1181 	s = splsoftnet();
1182 	in6pcb_disconnect(inp);
1183 	memset((void *)&in6p_laddr(inp), 0, sizeof(in6p_laddr(inp)));
1184 	splx(s);
1185 
1186 	so->so_state &= ~SS_ISCONNECTED;	/* XXX */
1187 	in6pcb_set_state(inp, INP_BOUND);		/* XXX */
1188 	return 0;
1189 }
1190 
1191 static int
1192 udp6_shutdown(struct socket *so)
1193 {
1194 	int s;
1195 
1196 	s = splsoftnet();
1197 	socantsendmore(so);
1198 	splx(s);
1199 
1200 	return 0;
1201 }
1202 
1203 static int
1204 udp6_abort(struct socket *so)
1205 {
1206 	int s;
1207 
1208 	KASSERT(solocked(so));
1209 	KASSERT(sotoinpcb(so) != NULL);
1210 
1211 	s = splsoftnet();
1212 	soisdisconnected(so);
1213 	inpcb_destroy(sotoinpcb(so));
1214 	splx(s);
1215 
1216 	return 0;
1217 }
1218 
1219 static int
1220 udp6_ioctl(struct socket *so, u_long cmd, void *addr6, struct ifnet *ifp)
1221 {
1222 	/*
1223 	 * MAPPED_ADDR implementation info:
1224 	 *  Mapped addr support for PRU_CONTROL is not necessary.
1225 	 *  Because typical user of PRU_CONTROL is such as ifconfig,
1226 	 *  and they don't associate any addr to their socket.  Then
1227 	 *  socket family is only hint about the PRU_CONTROL'ed address
1228 	 *  family, especially when getting addrs from kernel.
1229 	 *  So AF_INET socket need to be used to control AF_INET addrs,
1230 	 *  and AF_INET6 socket for AF_INET6 addrs.
1231 	 */
1232 	return in6_control(so, cmd, addr6, ifp);
1233 }
1234 
1235 static int
1236 udp6_stat(struct socket *so, struct stat *ub)
1237 {
1238 	KASSERT(solocked(so));
1239 
1240 	/* stat: don't bother with a blocksize */
1241 	return 0;
1242 }
1243 
1244 static int
1245 udp6_peeraddr(struct socket *so, struct sockaddr *nam)
1246 {
1247 	KASSERT(solocked(so));
1248 	KASSERT(sotoinpcb(so) != NULL);
1249 	KASSERT(nam != NULL);
1250 
1251 	in6pcb_fetch_peeraddr(sotoinpcb(so), (struct sockaddr_in6 *)nam);
1252 	return 0;
1253 }
1254 
1255 static int
1256 udp6_sockaddr(struct socket *so, struct sockaddr *nam)
1257 {
1258 	KASSERT(solocked(so));
1259 	KASSERT(sotoinpcb(so) != NULL);
1260 	KASSERT(nam != NULL);
1261 
1262 	in6pcb_fetch_sockaddr(sotoinpcb(so), (struct sockaddr_in6 *)nam);
1263 	return 0;
1264 }
1265 
1266 static int
1267 udp6_rcvd(struct socket *so, int flags, struct lwp *l)
1268 {
1269 	KASSERT(solocked(so));
1270 
1271 	return EOPNOTSUPP;
1272 }
1273 
1274 static int
1275 udp6_recvoob(struct socket *so, struct mbuf *m, int flags)
1276 {
1277 	KASSERT(solocked(so));
1278 
1279 	return EOPNOTSUPP;
1280 }
1281 
1282 static int
1283 udp6_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
1284     struct mbuf *control, struct lwp *l)
1285 {
1286 	struct inpcb *inp = sotoinpcb(so);
1287 	int error = 0;
1288 	int s;
1289 
1290 	KASSERT(solocked(so));
1291 	KASSERT(inp != NULL);
1292 	KASSERT(m != NULL);
1293 
1294 	s = splsoftnet();
1295 	error = udp6_output(inp, m, (struct sockaddr_in6 *)nam, control, l);
1296 	splx(s);
1297 
1298 	return error;
1299 }
1300 
1301 static int
1302 udp6_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
1303 {
1304 	KASSERT(solocked(so));
1305 
1306 	m_freem(m);
1307 	m_freem(control);
1308 
1309 	return EOPNOTSUPP;
1310 }
1311 
1312 static int
1313 udp6_purgeif(struct socket *so, struct ifnet *ifp)
1314 {
1315 
1316 	mutex_enter(softnet_lock);
1317 	in6pcb_purgeif0(&udbtable, ifp);
1318 #ifdef NET_MPSAFE
1319 	mutex_exit(softnet_lock);
1320 #endif
1321 	in6_purgeif(ifp);
1322 #ifdef NET_MPSAFE
1323 	mutex_enter(softnet_lock);
1324 #endif
1325 	in6pcb_purgeif(&udbtable, ifp);
1326 	mutex_exit(softnet_lock);
1327 
1328 	return 0;
1329 }
1330 
1331 static int
1332 sysctl_net_inet6_udp6_stats(SYSCTLFN_ARGS)
1333 {
1334 
1335 	return (NETSTAT_SYSCTL(udp6stat_percpu, UDP6_NSTATS));
1336 }
1337 
1338 static void
1339 sysctl_net_inet6_udp6_setup(struct sysctllog **clog)
1340 {
1341 
1342 	sysctl_createv(clog, 0, NULL, NULL,
1343 		       CTLFLAG_PERMANENT,
1344 		       CTLTYPE_NODE, "inet6", NULL,
1345 		       NULL, 0, NULL, 0,
1346 		       CTL_NET, PF_INET6, CTL_EOL);
1347 	sysctl_createv(clog, 0, NULL, NULL,
1348 		       CTLFLAG_PERMANENT,
1349 		       CTLTYPE_NODE, "udp6",
1350 		       SYSCTL_DESCR("UDPv6 related settings"),
1351 		       NULL, 0, NULL, 0,
1352 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_EOL);
1353 
1354 	sysctl_createv(clog, 0, NULL, NULL,
1355 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1356 		       CTLTYPE_INT, "sendspace",
1357 		       SYSCTL_DESCR("Default UDP send buffer size"),
1358 		       NULL, 0, &udp6_sendspace, 0,
1359 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_SENDSPACE,
1360 		       CTL_EOL);
1361 	sysctl_createv(clog, 0, NULL, NULL,
1362 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1363 		       CTLTYPE_INT, "recvspace",
1364 		       SYSCTL_DESCR("Default UDP receive buffer size"),
1365 		       NULL, 0, &udp6_recvspace, 0,
1366 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_RECVSPACE,
1367 		       CTL_EOL);
1368 	sysctl_createv(clog, 0, NULL, NULL,
1369 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1370 		       CTLTYPE_INT, "do_loopback_cksum",
1371 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
1372 		       NULL, 0, &udp_do_loopback_cksum, 0,
1373 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_LOOPBACKCKSUM,
1374 		       CTL_EOL);
1375 	sysctl_createv(clog, 0, NULL, NULL,
1376 		       CTLFLAG_PERMANENT,
1377 		       CTLTYPE_STRUCT, "pcblist",
1378 		       SYSCTL_DESCR("UDP protocol control block list"),
1379 		       sysctl_inpcblist, 0, &udbtable, 0,
1380 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_CREATE,
1381 		       CTL_EOL);
1382 	sysctl_createv(clog, 0, NULL, NULL,
1383 		       CTLFLAG_PERMANENT,
1384 		       CTLTYPE_STRUCT, "stats",
1385 		       SYSCTL_DESCR("UDPv6 statistics"),
1386 		       sysctl_net_inet6_udp6_stats, 0, NULL, 0,
1387 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_STATS,
1388 		       CTL_EOL);
1389 }
1390 
1391 void
1392 udp6_statinc(u_int stat)
1393 {
1394 
1395 	KASSERT(stat < UDP6_NSTATS);
1396 	UDP6_STATINC(stat);
1397 }
1398 
1399 #ifdef IPSEC
1400 /*
1401  * Returns:
1402  *     1 if the packet was processed
1403  *     0 if normal UDP processing should take place
1404  *    -1 if an error occurred and m was freed
1405  */
1406 static int
1407 udp6_espinudp(struct mbuf **mp, int off)
1408 {
1409 	const size_t skip = sizeof(struct udphdr);
1410 	size_t len;
1411 	void *data;
1412 	size_t minlen;
1413 	int ip6hdrlen;
1414 	struct ip6_hdr *ip6;
1415 	struct m_tag *tag;
1416 	struct udphdr *udphdr;
1417 	u_int16_t sport, dport;
1418 	struct mbuf *m = *mp;
1419 	uint32_t *marker;
1420 
1421 	/*
1422 	 * Collapse the mbuf chain if the first mbuf is too short
1423 	 * The longest case is: UDP + non ESP marker + ESP
1424 	 */
1425 	minlen = off + sizeof(u_int64_t) + sizeof(struct esp);
1426 	if (minlen > m->m_pkthdr.len)
1427 		minlen = m->m_pkthdr.len;
1428 
1429 	if (m->m_len < minlen) {
1430 		if ((*mp = m_pullup(m, minlen)) == NULL) {
1431 			return -1;
1432 		}
1433 		m = *mp;
1434 	}
1435 
1436 	len = m->m_len - off;
1437 	data = mtod(m, char *) + off;
1438 
1439 	/* Ignore keepalive packets */
1440 	if ((len == 1) && (*(unsigned char *)data == 0xff)) {
1441 		m_freem(m);
1442 		*mp = NULL; /* avoid any further processing by caller ... */
1443 		return 1;
1444 	}
1445 
1446 	/* Handle Non-ESP marker (32bit). If zero, then IKE. */
1447 	marker = (uint32_t *)data;
1448 	if (len <= sizeof(uint32_t))
1449 		return 0;
1450 	if (marker[0] == 0)
1451 		return 0;
1452 
1453 	/*
1454 	 * Get the UDP ports. They are handled in network
1455 	 * order everywhere in IPSEC_NAT_T code.
1456 	 */
1457 	udphdr = (struct udphdr *)((char *)data - skip);
1458 	sport = udphdr->uh_sport;
1459 	dport = udphdr->uh_dport;
1460 
1461 	/*
1462 	 * Remove the UDP header (and possibly the non ESP marker)
1463 	 * IPv6 header length is ip6hdrlen
1464 	 * Before:
1465 	 *   <---- off --->
1466 	 *   +-----+------+-----+
1467 	 *   | IP6 |  UDP | ESP |
1468 	 *   +-----+------+-----+
1469 	 *         <-skip->
1470 	 * After:
1471 	 *          +-----+-----+
1472 	 *          | IP6 | ESP |
1473 	 *          +-----+-----+
1474 	 *   <-skip->
1475 	 */
1476 	ip6hdrlen = off - sizeof(struct udphdr);
1477 	memmove(mtod(m, char *) + skip, mtod(m, void *), ip6hdrlen);
1478 	m_adj(m, skip);
1479 
1480 	ip6 = mtod(m, struct ip6_hdr *);
1481 	ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - skip);
1482 	ip6->ip6_nxt = IPPROTO_ESP;
1483 
1484 	/*
1485 	 * We have modified the packet - it is now ESP, so we should not
1486 	 * return to UDP processing ...
1487 	 *
1488 	 * Add a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember
1489 	 * the source UDP port. This is required if we want
1490 	 * to select the right SPD for multiple hosts behind
1491 	 * same NAT
1492 	 */
1493 	if ((tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS,
1494 	    sizeof(sport) + sizeof(dport), M_DONTWAIT)) == NULL) {
1495 		m_freem(m);
1496 		return -1;
1497 	}
1498 	((u_int16_t *)(tag + 1))[0] = sport;
1499 	((u_int16_t *)(tag + 1))[1] = dport;
1500 	m_tag_prepend(m, tag);
1501 
1502 	if (ipsec_used)
1503 		ipsec6_common_input(&m, &ip6hdrlen, IPPROTO_ESP);
1504 	else
1505 		m_freem(m);
1506 
1507 	/* We handled it, it shouldn't be handled by UDP */
1508 	*mp = NULL; /* avoid free by caller ... */
1509 	return 1;
1510 }
1511 #endif /* IPSEC */
1512 
1513 PR_WRAP_USRREQS(udp6)
1514 #define	udp6_attach	udp6_attach_wrapper
1515 #define	udp6_detach	udp6_detach_wrapper
1516 #define	udp6_accept	udp6_accept_wrapper
1517 #define	udp6_bind	udp6_bind_wrapper
1518 #define	udp6_listen	udp6_listen_wrapper
1519 #define	udp6_connect	udp6_connect_wrapper
1520 #define	udp6_connect2	udp6_connect2_wrapper
1521 #define	udp6_disconnect	udp6_disconnect_wrapper
1522 #define	udp6_shutdown	udp6_shutdown_wrapper
1523 #define	udp6_abort	udp6_abort_wrapper
1524 #define	udp6_ioctl	udp6_ioctl_wrapper
1525 #define	udp6_stat	udp6_stat_wrapper
1526 #define	udp6_peeraddr	udp6_peeraddr_wrapper
1527 #define	udp6_sockaddr	udp6_sockaddr_wrapper
1528 #define	udp6_rcvd	udp6_rcvd_wrapper
1529 #define	udp6_recvoob	udp6_recvoob_wrapper
1530 #define	udp6_send	udp6_send_wrapper
1531 #define	udp6_sendoob	udp6_sendoob_wrapper
1532 #define	udp6_purgeif	udp6_purgeif_wrapper
1533 
1534 const struct pr_usrreqs udp6_usrreqs = {
1535 	.pr_attach	= udp6_attach,
1536 	.pr_detach	= udp6_detach,
1537 	.pr_accept	= udp6_accept,
1538 	.pr_bind	= udp6_bind,
1539 	.pr_listen	= udp6_listen,
1540 	.pr_connect	= udp6_connect,
1541 	.pr_connect2	= udp6_connect2,
1542 	.pr_disconnect	= udp6_disconnect,
1543 	.pr_shutdown	= udp6_shutdown,
1544 	.pr_abort	= udp6_abort,
1545 	.pr_ioctl	= udp6_ioctl,
1546 	.pr_stat	= udp6_stat,
1547 	.pr_peeraddr	= udp6_peeraddr,
1548 	.pr_sockaddr	= udp6_sockaddr,
1549 	.pr_rcvd	= udp6_rcvd,
1550 	.pr_recvoob	= udp6_recvoob,
1551 	.pr_send	= udp6_send,
1552 	.pr_sendoob	= udp6_sendoob,
1553 	.pr_purgeif	= udp6_purgeif,
1554 };
1555