xref: /netbsd-src/sys/netinet6/udp6_usrreq.c (revision 796c32c94f6e154afc9de0f63da35c91bb739b45)
1 /*	$NetBSD: udp6_usrreq.c,v 1.130 2017/07/06 17:08:57 christos Exp $	*/
2 /*	$KAME: udp6_usrreq.c,v 1.86 2001/05/27 17:33:00 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1982, 1986, 1989, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
62  */
63 
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: udp6_usrreq.c,v 1.130 2017/07/06 17:08:57 christos Exp $");
66 
67 #ifdef _KERNEL_OPT
68 #include "opt_inet.h"
69 #include "opt_inet_csum.h"
70 #include "opt_ipsec.h"
71 #include "opt_net_mpsafe.h"
72 #endif
73 
74 #include <sys/param.h>
75 #include <sys/mbuf.h>
76 #include <sys/protosw.h>
77 #include <sys/socket.h>
78 #include <sys/socketvar.h>
79 #include <sys/systm.h>
80 #include <sys/proc.h>
81 #include <sys/syslog.h>
82 #include <sys/domain.h>
83 #include <sys/sysctl.h>
84 
85 #include <net/if.h>
86 #include <net/if_types.h>
87 
88 #include <netinet/in.h>
89 #include <netinet/in_var.h>
90 #include <netinet/in_systm.h>
91 #include <netinet/in_offload.h>
92 #include <netinet/ip.h>
93 #include <netinet/ip_var.h>
94 #include <netinet/in_pcb.h>
95 #include <netinet/udp.h>
96 #include <netinet/udp_var.h>
97 #include <netinet/udp_private.h>
98 
99 #include <netinet/ip6.h>
100 #include <netinet/icmp6.h>
101 #include <netinet6/ip6_var.h>
102 #include <netinet6/ip6_private.h>
103 #include <netinet6/in6_pcb.h>
104 #include <netinet6/udp6_var.h>
105 #include <netinet6/udp6_private.h>
106 #include <netinet6/ip6protosw.h>
107 #include <netinet6/scope6_var.h>
108 
109 #ifdef IPSEC
110 #include <netipsec/ipsec.h>
111 #include <netipsec/ipsec_var.h>
112 #include <netipsec/ipsec_private.h>
113 #ifdef INET6
114 #include <netipsec/ipsec6.h>
115 #endif
116 #endif	/* IPSEC */
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 in6pcb *, int);
138 static	void sysctl_net_inet6_udp6_setup(struct sysctllog **);
139 
140 #ifdef UDP_CSUM_COUNTERS
141 #include <sys/device.h>
142 struct evcnt udp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
143     NULL, "udp6", "hwcsum bad");
144 struct evcnt udp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
145     NULL, "udp6", "hwcsum ok");
146 struct evcnt udp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
147     NULL, "udp6", "hwcsum data");
148 struct evcnt udp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
149     NULL, "udp6", "swcsum");
150 
151 EVCNT_ATTACH_STATIC(udp6_hwcsum_bad);
152 EVCNT_ATTACH_STATIC(udp6_hwcsum_ok);
153 EVCNT_ATTACH_STATIC(udp6_hwcsum_data);
154 EVCNT_ATTACH_STATIC(udp6_swcsum);
155 
156 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
157 #else
158 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
159 #endif
160 
161 void
162 udp6_init(void)
163 {
164 	sysctl_net_inet6_udp6_setup(NULL);
165 	udp6stat_percpu = percpu_alloc(sizeof(uint64_t) * UDP6_NSTATS);
166 
167 	udp_init_common();
168 }
169 
170 /*
171  * Notify a udp user of an asynchronous error;
172  * just wake up so that he can collect error status.
173  */
174 static	void
175 udp6_notify(struct in6pcb *in6p, int errno)
176 {
177 	in6p->in6p_socket->so_error = errno;
178 	sorwakeup(in6p->in6p_socket);
179 	sowwakeup(in6p->in6p_socket);
180 }
181 
182 void *
183 udp6_ctlinput(int cmd, const struct sockaddr *sa, void *d)
184 {
185 	struct udphdr uh;
186 	struct ip6_hdr *ip6;
187 	const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa;
188 	struct mbuf *m;
189 	int off;
190 	void *cmdarg;
191 	struct ip6ctlparam *ip6cp = NULL;
192 	const struct sockaddr_in6 *sa6_src = NULL;
193 	void (*notify)(struct in6pcb *, int) = udp6_notify;
194 	struct udp_portonly {
195 		u_int16_t uh_sport;
196 		u_int16_t uh_dport;
197 	} *uhp;
198 
199 	if (sa->sa_family != AF_INET6 ||
200 	    sa->sa_len != sizeof(struct sockaddr_in6))
201 		return NULL;
202 
203 	if ((unsigned)cmd >= PRC_NCMDS)
204 		return NULL;
205 	if (PRC_IS_REDIRECT(cmd))
206 		notify = in6_rtchange, d = NULL;
207 	else if (cmd == PRC_HOSTDEAD)
208 		d = NULL;
209 	else if (cmd == PRC_MSGSIZE) {
210 		/* special code is present, see below */
211 		notify = in6_rtchange;
212 	}
213 	else if (inet6ctlerrmap[cmd] == 0)
214 		return NULL;
215 
216 	/* if the parameter is from icmp6, decode it. */
217 	if (d != NULL) {
218 		ip6cp = (struct ip6ctlparam *)d;
219 		m = ip6cp->ip6c_m;
220 		ip6 = ip6cp->ip6c_ip6;
221 		off = ip6cp->ip6c_off;
222 		cmdarg = ip6cp->ip6c_cmdarg;
223 		sa6_src = ip6cp->ip6c_src;
224 	} else {
225 		m = NULL;
226 		ip6 = NULL;
227 		cmdarg = NULL;
228 		sa6_src = &sa6_any;
229 		off = 0;
230 	}
231 
232 	if (ip6) {
233 		/*
234 		 * XXX: We assume that when IPV6 is non NULL,
235 		 * M and OFF are valid.
236 		 */
237 
238 		/* check if we can safely examine src and dst ports */
239 		if (m->m_pkthdr.len < off + sizeof(*uhp)) {
240 			if (cmd == PRC_MSGSIZE)
241 				icmp6_mtudisc_update((struct ip6ctlparam *)d, 0);
242 			return NULL;
243 		}
244 
245 		memset(&uh, 0, sizeof(uh));
246 		m_copydata(m, off, sizeof(*uhp), (void *)&uh);
247 
248 		if (cmd == PRC_MSGSIZE) {
249 			int valid = 0;
250 
251 			/*
252 			 * Check to see if we have a valid UDP socket
253 			 * corresponding to the address in the ICMPv6 message
254 			 * payload.
255 			 */
256 			if (in6_pcblookup_connect(&udbtable, &sa6->sin6_addr,
257 			    uh.uh_dport, (const struct in6_addr *)&sa6_src->sin6_addr,
258 						  uh.uh_sport, 0, 0))
259 				valid++;
260 #if 0
261 			/*
262 			 * As the use of sendto(2) is fairly popular,
263 			 * we may want to allow non-connected pcb too.
264 			 * But it could be too weak against attacks...
265 			 * We should at least check if the local address (= s)
266 			 * is really ours.
267 			 */
268 			else if (in6_pcblookup_bind(&udbtable, &sa6->sin6_addr,
269 			    uh.uh_dport, 0))
270 				valid++;
271 #endif
272 
273 			/*
274 			 * Depending on the value of "valid" and routing table
275 			 * size (mtudisc_{hi,lo}wat), we will:
276 			 * - recalculate the new MTU and create the
277 			 *   corresponding routing entry, or
278 			 * - ignore the MTU change notification.
279 			 */
280 			icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
281 
282 			/*
283 			 * regardless of if we called
284 			 * icmp6_mtudisc_update(), we need to call
285 			 * in6_pcbnotify(), to notify path MTU change
286 			 * to the userland (RFC3542), because some
287 			 * unconnected sockets may share the same
288 			 * destination and want to know the path MTU.
289 			 */
290 		}
291 
292 		(void) in6_pcbnotify(&udbtable, sa, uh.uh_dport,
293 		    sin6tocsa(sa6_src), uh.uh_sport, cmd, cmdarg,
294 		    notify);
295 	} else {
296 		(void) in6_pcbnotify(&udbtable, sa, 0,
297 		    sin6tocsa(sa6_src), 0, cmd, cmdarg, notify);
298 	}
299 	return NULL;
300 }
301 
302 int
303 udp6_ctloutput(int op, struct socket *so, struct sockopt *sopt)
304 {
305 	int s;
306 	int error = 0;
307 	int family;
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 	error = EINVAL;
334 
335 end:
336 	splx(s);
337 	return error;
338 }
339 
340 static void
341 udp6_sendup(struct mbuf *m, int off /* offset of data portion */,
342 	struct sockaddr *src, struct socket *so)
343 {
344 	struct mbuf *opts = NULL;
345 	struct mbuf *n;
346 	struct in6pcb *in6p;
347 
348 	KASSERT(so != NULL);
349 	KASSERT(so->so_proto->pr_domain->dom_family == AF_INET6);
350 	in6p = sotoin6pcb(so);
351 	KASSERT(in6p != NULL);
352 
353 #if defined(IPSEC)
354 	/* check AH/ESP integrity. */
355 	if (ipsec_used && ipsec6_in_reject(m, in6p)) {
356 		IPSEC6_STATINC(IPSEC_STAT_IN_POLVIO);
357 		if ((n = m_copypacket(m, M_DONTWAIT)) != NULL)
358 			icmp6_error(n, ICMP6_DST_UNREACH,
359 			    ICMP6_DST_UNREACH_ADMIN, 0);
360 		return;
361 	}
362 #endif /*IPSEC*/
363 
364 	if ((n = m_copypacket(m, M_DONTWAIT)) != NULL) {
365 		if (in6p->in6p_flags & IN6P_CONTROLOPTS
366 		    || SOOPT_TIMESTAMP(in6p->in6p_socket->so_options)) {
367 			struct ip6_hdr *ip6 = mtod(n, struct ip6_hdr *);
368 			ip6_savecontrol(in6p, &opts, ip6, n);
369 		}
370 
371 		m_adj(n, off);
372 		if (sbappendaddr(&so->so_rcv, src, n, opts) == 0) {
373 			m_freem(n);
374 			if (opts)
375 				m_freem(opts);
376 			so->so_rcv.sb_overflowed++;
377 			UDP6_STATINC(UDP6_STAT_FULLSOCK);
378 		} else
379 			sorwakeup(so);
380 	}
381 }
382 
383 int
384 udp6_realinput(int af, struct sockaddr_in6 *src, struct sockaddr_in6 *dst,
385 	struct mbuf *m, int off)
386 {
387 	u_int16_t sport, dport;
388 	int rcvcnt;
389 	struct in6_addr src6, *dst6;
390 	const struct in_addr *dst4;
391 	struct inpcb_hdr *inph;
392 	struct in6pcb *in6p;
393 
394 	rcvcnt = 0;
395 	off += sizeof(struct udphdr);	/* now, offset of payload */
396 
397 	if (af != AF_INET && af != AF_INET6)
398 		goto bad;
399 	if (src->sin6_family != AF_INET6 || dst->sin6_family != AF_INET6)
400 		goto bad;
401 
402 	src6 = src->sin6_addr;
403 	if (sa6_recoverscope(src) != 0) {
404 		/* XXX: should be impossible. */
405 		goto bad;
406 	}
407 	sport = src->sin6_port;
408 
409 	dport = dst->sin6_port;
410 	dst4 = (struct in_addr *)&dst->sin6_addr.s6_addr[12];
411 	dst6 = &dst->sin6_addr;
412 
413 	if (IN6_IS_ADDR_MULTICAST(dst6) ||
414 	    (af == AF_INET && IN_MULTICAST(dst4->s_addr))) {
415 		/*
416 		 * Deliver a multicast or broadcast datagram to *all* sockets
417 		 * for which the local and remote addresses and ports match
418 		 * those of the incoming datagram.  This allows more than
419 		 * one process to receive multi/broadcasts on the same port.
420 		 * (This really ought to be done for unicast datagrams as
421 		 * well, but that would cause problems with existing
422 		 * applications that open both address-specific sockets and
423 		 * a wildcard socket listening to the same port -- they would
424 		 * end up receiving duplicates of every unicast datagram.
425 		 * Those applications open the multiple sockets to overcome an
426 		 * inadequacy of the UDP socket interface, but for backwards
427 		 * compatibility we avoid the problem here rather than
428 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
429 		 */
430 
431 		/*
432 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
433 		 * we need udpiphdr for IPsec processing so we do that later.
434 		 */
435 		/*
436 		 * Locate pcb(s) for datagram.
437 		 */
438 		TAILQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
439 			in6p = (struct in6pcb *)inph;
440 			if (in6p->in6p_af != AF_INET6)
441 				continue;
442 
443 			if (in6p->in6p_lport != dport)
444 				continue;
445 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
446 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
447 				    dst6))
448 					continue;
449 			} else {
450 				if (IN6_IS_ADDR_V4MAPPED(dst6) &&
451 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
452 					continue;
453 			}
454 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
455 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
456 				    &src6) || in6p->in6p_fport != sport)
457 					continue;
458 			} else {
459 				if (IN6_IS_ADDR_V4MAPPED(&src6) &&
460 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
461 					continue;
462 			}
463 
464 			udp6_sendup(m, off, sin6tosa(src), in6p->in6p_socket);
465 			rcvcnt++;
466 
467 			/*
468 			 * Don't look for additional matches if this one does
469 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
470 			 * socket options set.  This heuristic avoids searching
471 			 * through all pcbs in the common case of a non-shared
472 			 * port.  It assumes that an application will never
473 			 * clear these options after setting them.
474 			 */
475 			if ((in6p->in6p_socket->so_options &
476 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
477 				break;
478 		}
479 	} else {
480 		/*
481 		 * Locate pcb for datagram.
482 		 */
483 		in6p = in6_pcblookup_connect(&udbtable, &src6, sport, dst6,
484 					     dport, 0, 0);
485 		if (in6p == 0) {
486 			UDP_STATINC(UDP_STAT_PCBHASHMISS);
487 			in6p = in6_pcblookup_bind(&udbtable, dst6, dport, 0);
488 			if (in6p == 0)
489 				return rcvcnt;
490 		}
491 
492 		udp6_sendup(m, off, sin6tosa(src), in6p->in6p_socket);
493 		rcvcnt++;
494 	}
495 
496 bad:
497 	return rcvcnt;
498 }
499 
500 int
501 udp6_input_checksum(struct mbuf *m, const struct udphdr *uh, int off, int len)
502 {
503 
504 	/*
505 	 * XXX it's better to record and check if this mbuf is
506 	 * already checked.
507 	 */
508 
509 	if (__predict_false((m->m_flags & M_LOOP) && !udp_do_loopback_cksum)) {
510 		goto good;
511 	}
512 	if (uh->uh_sum == 0) {
513 		UDP6_STATINC(UDP6_STAT_NOSUM);
514 		goto bad;
515 	}
516 
517 	switch (m->m_pkthdr.csum_flags &
518 	    ((m_get_rcvif_NOMPSAFE(m)->if_csum_flags_rx & M_CSUM_UDPv6) |
519 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
520 	case M_CSUM_UDPv6|M_CSUM_TCP_UDP_BAD:
521 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_bad);
522 		UDP6_STATINC(UDP6_STAT_BADSUM);
523 		goto bad;
524 
525 #if 0 /* notyet */
526 	case M_CSUM_UDPv6|M_CSUM_DATA:
527 #endif
528 
529 	case M_CSUM_UDPv6:
530 		/* Checksum was okay. */
531 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_ok);
532 		break;
533 
534 	default:
535 		/*
536 		 * Need to compute it ourselves.  Maybe skip checksum
537 		 * on loopback interfaces.
538 		 */
539 		UDP_CSUM_COUNTER_INCR(&udp6_swcsum);
540 		if (in6_cksum(m, IPPROTO_UDP, off, len) != 0) {
541 			UDP6_STATINC(UDP6_STAT_BADSUM);
542 			goto bad;
543 		}
544 	}
545 
546 good:
547 	return 0;
548 bad:
549 	return -1;
550 }
551 
552 int
553 udp6_input(struct mbuf **mp, int *offp, int proto)
554 {
555 	struct mbuf *m = *mp;
556 	int off = *offp;
557 	struct sockaddr_in6 src, dst;
558 	struct ip6_hdr *ip6;
559 	struct udphdr *uh;
560 	u_int32_t plen, ulen;
561 
562 	ip6 = mtod(m, struct ip6_hdr *);
563 
564 #if defined(NFAITH) && 0 < NFAITH
565 	if (faithprefix(&ip6->ip6_dst)) {
566 		/* send icmp6 host unreach? */
567 		m_freem(m);
568 		return IPPROTO_DONE;
569 	}
570 #endif
571 
572 	UDP6_STATINC(UDP6_STAT_IPACKETS);
573 
574 	/* check for jumbogram is done in ip6_input.  we can trust pkthdr.len */
575 	plen = m->m_pkthdr.len - off;
576 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
577 	if (uh == NULL) {
578 		IP6_STATINC(IP6_STAT_TOOSHORT);
579 		return IPPROTO_DONE;
580 	}
581 	/*
582 	 * Enforce alignment requirements that are violated in
583 	 * some cases, see kern/50766 for details.
584 	 */
585         if (UDP_HDR_ALIGNED_P(uh) == 0) {
586                 m = m_copyup(m, off + sizeof(struct udphdr), 0);
587                 if (m == NULL) {
588                         IP6_STATINC(IP6_STAT_TOOSHORT);
589                         return IPPROTO_DONE;
590                 }
591 		ip6 = mtod(m, struct ip6_hdr *);
592                 uh = (struct udphdr *)(mtod(m, char *) + off);
593         }
594 	KASSERT(UDP_HDR_ALIGNED_P(uh));
595 	ulen = ntohs((u_short)uh->uh_ulen);
596 	/*
597 	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
598 	 * iff payload length > 0xffff.
599 	 */
600 	if (ulen == 0 && plen > 0xffff)
601 		ulen = plen;
602 
603 	if (plen != ulen) {
604 		UDP6_STATINC(UDP6_STAT_BADLEN);
605 		goto bad;
606 	}
607 
608 	/* destination port of 0 is illegal, based on RFC768. */
609 	if (uh->uh_dport == 0)
610 		goto bad;
611 
612 	/* Be proactive about malicious use of IPv4 mapped address */
613 	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
614 	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
615 		/* XXX stat */
616 		goto bad;
617 	}
618 
619 	/*
620 	 * Checksum extended UDP header and data.  Maybe skip checksum
621 	 * on loopback interfaces.
622 	 */
623 	if (udp6_input_checksum(m, uh, off, ulen))
624 		goto bad;
625 
626 	/*
627 	 * Construct source and dst sockaddrs.
628 	 */
629 	memset(&src, 0, sizeof(src));
630 	src.sin6_family = AF_INET6;
631 	src.sin6_len = sizeof(struct sockaddr_in6);
632 	src.sin6_addr = ip6->ip6_src;
633 	src.sin6_port = uh->uh_sport;
634 	memset(&dst, 0, sizeof(dst));
635 	dst.sin6_family = AF_INET6;
636 	dst.sin6_len = sizeof(struct sockaddr_in6);
637 	dst.sin6_addr = ip6->ip6_dst;
638 	dst.sin6_port = uh->uh_dport;
639 
640 	if (udp6_realinput(AF_INET6, &src, &dst, m, off) == 0) {
641 		if (m->m_flags & M_MCAST) {
642 			UDP6_STATINC(UDP6_STAT_NOPORTMCAST);
643 			goto bad;
644 		}
645 		UDP6_STATINC(UDP6_STAT_NOPORT);
646 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
647 		m = NULL;
648 	}
649 
650 bad:
651 	if (m)
652 		m_freem(m);
653 	return IPPROTO_DONE;
654 }
655 
656 static int
657 udp6_attach(struct socket *so, int proto)
658 {
659 	struct in6pcb *in6p;
660 	int s, error;
661 
662 	KASSERT(sotoin6pcb(so) == NULL);
663 	sosetlock(so);
664 
665 	/*
666 	 * MAPPED_ADDR implementation spec:
667 	 *  Always attach for IPv6, and only when necessary for IPv4.
668 	 */
669 	s = splsoftnet();
670 	error = in6_pcballoc(so, &udbtable);
671 	splx(s);
672 	if (error) {
673 		return error;
674 	}
675 	error = soreserve(so, udp6_sendspace, udp6_recvspace);
676 	if (error) {
677 		return error;
678 	}
679 	in6p = sotoin6pcb(so);
680 	in6p->in6p_cksum = -1;	/* just to be sure */
681 
682 	KASSERT(solocked(so));
683 	return 0;
684 }
685 
686 static void
687 udp6_detach(struct socket *so)
688 {
689 	struct in6pcb *in6p = sotoin6pcb(so);
690 	int s;
691 
692 	KASSERT(solocked(so));
693 	KASSERT(in6p != NULL);
694 
695 	s = splsoftnet();
696 	in6_pcbdetach(in6p);
697 	splx(s);
698 }
699 
700 static int
701 udp6_accept(struct socket *so, struct sockaddr *nam)
702 {
703 	KASSERT(solocked(so));
704 
705 	return EOPNOTSUPP;
706 }
707 
708 static int
709 udp6_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
710 {
711 	struct in6pcb *in6p = sotoin6pcb(so);
712 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
713 	int error = 0;
714 	int s;
715 
716 	KASSERT(solocked(so));
717 	KASSERT(in6p != NULL);
718 
719 	s = splsoftnet();
720 	error = in6_pcbbind(in6p, sin6, l);
721 	splx(s);
722 	return error;
723 }
724 
725 static int
726 udp6_listen(struct socket *so, struct lwp *l)
727 {
728 	KASSERT(solocked(so));
729 
730 	return EOPNOTSUPP;
731 }
732 
733 static int
734 udp6_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
735 {
736 	struct in6pcb *in6p = sotoin6pcb(so);
737 	int error = 0;
738 	int s;
739 
740 	KASSERT(solocked(so));
741 	KASSERT(in6p != NULL);
742 
743 	if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr))
744 		return EISCONN;
745 	s = splsoftnet();
746 	error = in6_pcbconnect(in6p, (struct sockaddr_in6 *)nam, l);
747 	splx(s);
748 	if (error == 0)
749 		soisconnected(so);
750 
751 	return error;
752 }
753 
754 static int
755 udp6_connect2(struct socket *so, struct socket *so2)
756 {
757 	KASSERT(solocked(so));
758 
759 	return EOPNOTSUPP;
760 }
761 
762 static int
763 udp6_disconnect(struct socket *so)
764 {
765 	struct in6pcb *in6p = sotoin6pcb(so);
766 	int s;
767 
768 	KASSERT(solocked(so));
769 	KASSERT(in6p != NULL);
770 
771 	if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr))
772 		return ENOTCONN;
773 
774 	s = splsoftnet();
775 	in6_pcbdisconnect(in6p);
776 	memset((void *)&in6p->in6p_laddr, 0, sizeof(in6p->in6p_laddr));
777 	splx(s);
778 
779 	so->so_state &= ~SS_ISCONNECTED;	/* XXX */
780 	in6_pcbstate(in6p, IN6P_BOUND);		/* XXX */
781 	return 0;
782 }
783 
784 static int
785 udp6_shutdown(struct socket *so)
786 {
787 	int s;
788 
789 	s = splsoftnet();
790 	socantsendmore(so);
791 	splx(s);
792 
793 	return 0;
794 }
795 
796 static int
797 udp6_abort(struct socket *so)
798 {
799 	int s;
800 
801 	KASSERT(solocked(so));
802 	KASSERT(sotoin6pcb(so) != NULL);
803 
804 	s = splsoftnet();
805 	soisdisconnected(so);
806 	in6_pcbdetach(sotoin6pcb(so));
807 	splx(s);
808 
809 	return 0;
810 }
811 
812 static int
813 udp6_ioctl(struct socket *so, u_long cmd, void *addr6, struct ifnet *ifp)
814 {
815 	/*
816 	 * MAPPED_ADDR implementation info:
817 	 *  Mapped addr support for PRU_CONTROL is not necessary.
818 	 *  Because typical user of PRU_CONTROL is such as ifconfig,
819 	 *  and they don't associate any addr to their socket.  Then
820 	 *  socket family is only hint about the PRU_CONTROL'ed address
821 	 *  family, especially when getting addrs from kernel.
822 	 *  So AF_INET socket need to be used to control AF_INET addrs,
823 	 *  and AF_INET6 socket for AF_INET6 addrs.
824 	 */
825 	return in6_control(so, cmd, addr6, ifp);
826 }
827 
828 static int
829 udp6_stat(struct socket *so, struct stat *ub)
830 {
831 	KASSERT(solocked(so));
832 
833 	/* stat: don't bother with a blocksize */
834 	return 0;
835 }
836 
837 static int
838 udp6_peeraddr(struct socket *so, struct sockaddr *nam)
839 {
840 	KASSERT(solocked(so));
841 	KASSERT(sotoin6pcb(so) != NULL);
842 	KASSERT(nam != NULL);
843 
844 	in6_setpeeraddr(sotoin6pcb(so), (struct sockaddr_in6 *)nam);
845 	return 0;
846 }
847 
848 static int
849 udp6_sockaddr(struct socket *so, struct sockaddr *nam)
850 {
851 	KASSERT(solocked(so));
852 	KASSERT(sotoin6pcb(so) != NULL);
853 	KASSERT(nam != NULL);
854 
855 	in6_setsockaddr(sotoin6pcb(so), (struct sockaddr_in6 *)nam);
856 	return 0;
857 }
858 
859 static int
860 udp6_rcvd(struct socket *so, int flags, struct lwp *l)
861 {
862 	KASSERT(solocked(so));
863 
864 	return EOPNOTSUPP;
865 }
866 
867 static int
868 udp6_recvoob(struct socket *so, struct mbuf *m, int flags)
869 {
870 	KASSERT(solocked(so));
871 
872 	return EOPNOTSUPP;
873 }
874 
875 static int
876 udp6_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
877     struct mbuf *control, struct lwp *l)
878 {
879 	struct in6pcb *in6p = sotoin6pcb(so);
880 	int error = 0;
881 	int s;
882 
883 	KASSERT(solocked(so));
884 	KASSERT(in6p != NULL);
885 	KASSERT(m != NULL);
886 
887 	s = splsoftnet();
888 	error = udp6_output(in6p, m, (struct sockaddr_in6 *)nam, control, l);
889 	splx(s);
890 
891 	return error;
892 }
893 
894 static int
895 udp6_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
896 {
897 	KASSERT(solocked(so));
898 
899 	if (m)
900 		m_freem(m);
901 	if (control)
902 		m_freem(control);
903 
904 	return EOPNOTSUPP;
905 }
906 
907 static int
908 udp6_purgeif(struct socket *so, struct ifnet *ifp)
909 {
910 
911 	mutex_enter(softnet_lock);
912 	in6_pcbpurgeif0(&udbtable, ifp);
913 #ifdef NET_MPSAFE
914 	mutex_exit(softnet_lock);
915 #endif
916 	in6_purgeif(ifp);
917 #ifdef NET_MPSAFE
918 	mutex_enter(softnet_lock);
919 #endif
920 	in6_pcbpurgeif(&udbtable, ifp);
921 	mutex_exit(softnet_lock);
922 
923 	return 0;
924 }
925 
926 static int
927 sysctl_net_inet6_udp6_stats(SYSCTLFN_ARGS)
928 {
929 
930 	return (NETSTAT_SYSCTL(udp6stat_percpu, UDP6_NSTATS));
931 }
932 
933 static void
934 sysctl_net_inet6_udp6_setup(struct sysctllog **clog)
935 {
936 
937 	sysctl_createv(clog, 0, NULL, NULL,
938 		       CTLFLAG_PERMANENT,
939 		       CTLTYPE_NODE, "inet6", NULL,
940 		       NULL, 0, NULL, 0,
941 		       CTL_NET, PF_INET6, CTL_EOL);
942 	sysctl_createv(clog, 0, NULL, NULL,
943 		       CTLFLAG_PERMANENT,
944 		       CTLTYPE_NODE, "udp6",
945 		       SYSCTL_DESCR("UDPv6 related settings"),
946 		       NULL, 0, NULL, 0,
947 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_EOL);
948 
949 	sysctl_createv(clog, 0, NULL, NULL,
950 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
951 		       CTLTYPE_INT, "sendspace",
952 		       SYSCTL_DESCR("Default UDP send buffer size"),
953 		       NULL, 0, &udp6_sendspace, 0,
954 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_SENDSPACE,
955 		       CTL_EOL);
956 	sysctl_createv(clog, 0, NULL, NULL,
957 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
958 		       CTLTYPE_INT, "recvspace",
959 		       SYSCTL_DESCR("Default UDP receive buffer size"),
960 		       NULL, 0, &udp6_recvspace, 0,
961 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_RECVSPACE,
962 		       CTL_EOL);
963 	sysctl_createv(clog, 0, NULL, NULL,
964 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
965 		       CTLTYPE_INT, "do_loopback_cksum",
966 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
967 		       NULL, 0, &udp_do_loopback_cksum, 0,
968 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_LOOPBACKCKSUM,
969 		       CTL_EOL);
970 	sysctl_createv(clog, 0, NULL, NULL,
971 		       CTLFLAG_PERMANENT,
972 		       CTLTYPE_STRUCT, "pcblist",
973 		       SYSCTL_DESCR("UDP protocol control block list"),
974 		       sysctl_inpcblist, 0, &udbtable, 0,
975 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_CREATE,
976 		       CTL_EOL);
977 	sysctl_createv(clog, 0, NULL, NULL,
978 		       CTLFLAG_PERMANENT,
979 		       CTLTYPE_STRUCT, "stats",
980 		       SYSCTL_DESCR("UDPv6 statistics"),
981 		       sysctl_net_inet6_udp6_stats, 0, NULL, 0,
982 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_STATS,
983 		       CTL_EOL);
984 }
985 
986 void
987 udp6_statinc(u_int stat)
988 {
989 
990 	KASSERT(stat < UDP6_NSTATS);
991 	UDP6_STATINC(stat);
992 }
993 
994 PR_WRAP_USRREQS(udp6)
995 #define	udp6_attach	udp6_attach_wrapper
996 #define	udp6_detach	udp6_detach_wrapper
997 #define	udp6_accept	udp6_accept_wrapper
998 #define	udp6_bind	udp6_bind_wrapper
999 #define	udp6_listen	udp6_listen_wrapper
1000 #define	udp6_connect	udp6_connect_wrapper
1001 #define	udp6_connect2	udp6_connect2_wrapper
1002 #define	udp6_disconnect	udp6_disconnect_wrapper
1003 #define	udp6_shutdown	udp6_shutdown_wrapper
1004 #define	udp6_abort	udp6_abort_wrapper
1005 #define	udp6_ioctl	udp6_ioctl_wrapper
1006 #define	udp6_stat	udp6_stat_wrapper
1007 #define	udp6_peeraddr	udp6_peeraddr_wrapper
1008 #define	udp6_sockaddr	udp6_sockaddr_wrapper
1009 #define	udp6_rcvd	udp6_rcvd_wrapper
1010 #define	udp6_recvoob	udp6_recvoob_wrapper
1011 #define	udp6_send	udp6_send_wrapper
1012 #define	udp6_sendoob	udp6_sendoob_wrapper
1013 #define	udp6_purgeif	udp6_purgeif_wrapper
1014 
1015 const struct pr_usrreqs udp6_usrreqs = {
1016 	.pr_attach	= udp6_attach,
1017 	.pr_detach	= udp6_detach,
1018 	.pr_accept	= udp6_accept,
1019 	.pr_bind	= udp6_bind,
1020 	.pr_listen	= udp6_listen,
1021 	.pr_connect	= udp6_connect,
1022 	.pr_connect2	= udp6_connect2,
1023 	.pr_disconnect	= udp6_disconnect,
1024 	.pr_shutdown	= udp6_shutdown,
1025 	.pr_abort	= udp6_abort,
1026 	.pr_ioctl	= udp6_ioctl,
1027 	.pr_stat	= udp6_stat,
1028 	.pr_peeraddr	= udp6_peeraddr,
1029 	.pr_sockaddr	= udp6_sockaddr,
1030 	.pr_rcvd	= udp6_rcvd,
1031 	.pr_recvoob	= udp6_recvoob,
1032 	.pr_send	= udp6_send,
1033 	.pr_sendoob	= udp6_sendoob,
1034 	.pr_purgeif	= udp6_purgeif,
1035 };
1036