xref: /netbsd-src/sys/netinet6/udp6_usrreq.c (revision a24efa7dea9f1f56c3bdb15a927d3516792ace1c)
1 /*	$NetBSD: udp6_usrreq.c,v 1.122 2016/04/26 08:44:45 ozaki-r 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 1.122 2016/04/26 08:44:45 ozaki-r Exp $");
66 
67 #ifdef _KERNEL_OPT
68 #include "opt_inet.h"
69 #include "opt_inet_csum.h"
70 #include "opt_ipsec.h"
71 #endif
72 
73 #include <sys/param.h>
74 #include <sys/mbuf.h>
75 #include <sys/protosw.h>
76 #include <sys/socket.h>
77 #include <sys/socketvar.h>
78 #include <sys/systm.h>
79 #include <sys/proc.h>
80 #include <sys/syslog.h>
81 #include <sys/domain.h>
82 #include <sys/sysctl.h>
83 
84 #include <net/if.h>
85 #include <net/if_types.h>
86 
87 #include <netinet/in.h>
88 #include <netinet/in_var.h>
89 #include <netinet/in_systm.h>
90 #include <netinet/in_offload.h>
91 #include <netinet/ip.h>
92 #include <netinet/ip_var.h>
93 #include <netinet/in_pcb.h>
94 #include <netinet/udp.h>
95 #include <netinet/udp_var.h>
96 #include <netinet/udp_private.h>
97 
98 #include <netinet/ip6.h>
99 #include <netinet/icmp6.h>
100 #include <netinet6/ip6_var.h>
101 #include <netinet6/ip6_private.h>
102 #include <netinet6/in6_pcb.h>
103 #include <netinet6/udp6_var.h>
104 #include <netinet6/udp6_private.h>
105 #include <netinet6/ip6protosw.h>
106 #include <netinet6/scope6_var.h>
107 
108 #ifdef IPSEC
109 #include <netipsec/ipsec.h>
110 #include <netipsec/ipsec_var.h>
111 #include <netipsec/ipsec_private.h>
112 #ifdef INET6
113 #include <netipsec/ipsec6.h>
114 #endif
115 #endif	/* IPSEC */
116 
117 #include "faith.h"
118 #if defined(NFAITH) && NFAITH > 0
119 #include <net/if_faith.h>
120 #endif
121 
122 /*
123  * UDP protocol implementation.
124  * Per RFC 768, August, 1980.
125  */
126 
127 extern struct inpcbtable udbtable;
128 
129 percpu_t *udp6stat_percpu;
130 
131 /* UDP on IP6 parameters */
132 static int	udp6_sendspace = 9216;	/* really max datagram size */
133 static int	udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
134 					/* 40 1K datagrams */
135 
136 static	void udp6_notify(struct in6pcb *, int);
137 static	void sysctl_net_inet6_udp6_setup(struct sysctllog **);
138 
139 #ifdef UDP_CSUM_COUNTERS
140 #include <sys/device.h>
141 struct evcnt udp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
142     NULL, "udp6", "hwcsum bad");
143 struct evcnt udp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
144     NULL, "udp6", "hwcsum ok");
145 struct evcnt udp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
146     NULL, "udp6", "hwcsum data");
147 struct evcnt udp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC,
148     NULL, "udp6", "swcsum");
149 
150 EVCNT_ATTACH_STATIC(udp6_hwcsum_bad);
151 EVCNT_ATTACH_STATIC(udp6_hwcsum_ok);
152 EVCNT_ATTACH_STATIC(udp6_hwcsum_data);
153 EVCNT_ATTACH_STATIC(udp6_swcsum);
154 
155 #define	UDP_CSUM_COUNTER_INCR(ev)	(ev)->ev_count++
156 #else
157 #define	UDP_CSUM_COUNTER_INCR(ev)	/* nothing */
158 #endif
159 
160 void
161 udp6_init(void)
162 {
163 	sysctl_net_inet6_udp6_setup(NULL);
164 	udp6stat_percpu = percpu_alloc(sizeof(uint64_t) * UDP6_NSTATS);
165 
166 	udp_init_common();
167 }
168 
169 /*
170  * Notify a udp user of an asynchronous error;
171  * just wake up so that he can collect error status.
172  */
173 static	void
174 udp6_notify(struct in6pcb *in6p, int errno)
175 {
176 	in6p->in6p_socket->so_error = errno;
177 	sorwakeup(in6p->in6p_socket);
178 	sowwakeup(in6p->in6p_socket);
179 }
180 
181 void *
182 udp6_ctlinput(int cmd, const struct sockaddr *sa, void *d)
183 {
184 	struct udphdr uh;
185 	struct ip6_hdr *ip6;
186 	const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa;
187 	struct mbuf *m;
188 	int off;
189 	void *cmdarg;
190 	struct ip6ctlparam *ip6cp = NULL;
191 	const struct sockaddr_in6 *sa6_src = NULL;
192 	void (*notify)(struct in6pcb *, int) = udp6_notify;
193 	struct udp_portonly {
194 		u_int16_t uh_sport;
195 		u_int16_t uh_dport;
196 	} *uhp;
197 
198 	if (sa->sa_family != AF_INET6 ||
199 	    sa->sa_len != sizeof(struct sockaddr_in6))
200 		return NULL;
201 
202 	if ((unsigned)cmd >= PRC_NCMDS)
203 		return NULL;
204 	if (PRC_IS_REDIRECT(cmd))
205 		notify = in6_rtchange, d = NULL;
206 	else if (cmd == PRC_HOSTDEAD)
207 		d = NULL;
208 	else if (cmd == PRC_MSGSIZE) {
209 		/* special code is present, see below */
210 		notify = in6_rtchange;
211 	}
212 	else if (inet6ctlerrmap[cmd] == 0)
213 		return NULL;
214 
215 	/* if the parameter is from icmp6, decode it. */
216 	if (d != NULL) {
217 		ip6cp = (struct ip6ctlparam *)d;
218 		m = ip6cp->ip6c_m;
219 		ip6 = ip6cp->ip6c_ip6;
220 		off = ip6cp->ip6c_off;
221 		cmdarg = ip6cp->ip6c_cmdarg;
222 		sa6_src = ip6cp->ip6c_src;
223 	} else {
224 		m = NULL;
225 		ip6 = NULL;
226 		cmdarg = NULL;
227 		sa6_src = &sa6_any;
228 		off = 0;
229 	}
230 
231 	if (ip6) {
232 		/*
233 		 * XXX: We assume that when IPV6 is non NULL,
234 		 * M and OFF are valid.
235 		 */
236 
237 		/* check if we can safely examine src and dst ports */
238 		if (m->m_pkthdr.len < off + sizeof(*uhp)) {
239 			if (cmd == PRC_MSGSIZE)
240 				icmp6_mtudisc_update((struct ip6ctlparam *)d, 0);
241 			return NULL;
242 		}
243 
244 		memset(&uh, 0, sizeof(uh));
245 		m_copydata(m, off, sizeof(*uhp), (void *)&uh);
246 
247 		if (cmd == PRC_MSGSIZE) {
248 			int valid = 0;
249 
250 			/*
251 			 * Check to see if we have a valid UDP socket
252 			 * corresponding to the address in the ICMPv6 message
253 			 * payload.
254 			 */
255 			if (in6_pcblookup_connect(&udbtable, &sa6->sin6_addr,
256 			    uh.uh_dport, (const struct in6_addr *)&sa6_src->sin6_addr,
257 						  uh.uh_sport, 0, 0))
258 				valid++;
259 #if 0
260 			/*
261 			 * As the use of sendto(2) is fairly popular,
262 			 * we may want to allow non-connected pcb too.
263 			 * But it could be too weak against attacks...
264 			 * We should at least check if the local address (= s)
265 			 * is really ours.
266 			 */
267 			else if (in6_pcblookup_bind(&udbtable, &sa6->sin6_addr,
268 			    uh.uh_dport, 0))
269 				valid++;
270 #endif
271 
272 			/*
273 			 * Depending on the value of "valid" and routing table
274 			 * size (mtudisc_{hi,lo}wat), we will:
275 			 * - recalculate the new MTU and create the
276 			 *   corresponding routing entry, or
277 			 * - ignore the MTU change notification.
278 			 */
279 			icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
280 
281 			/*
282 			 * regardless of if we called
283 			 * icmp6_mtudisc_update(), we need to call
284 			 * in6_pcbnotify(), to notify path MTU change
285 			 * to the userland (RFC3542), because some
286 			 * unconnected sockets may share the same
287 			 * destination and want to know the path MTU.
288 			 */
289 		}
290 
291 		(void) in6_pcbnotify(&udbtable, sa, uh.uh_dport,
292 		    (const struct sockaddr *)sa6_src, uh.uh_sport, cmd, cmdarg,
293 		    notify);
294 	} else {
295 		(void) in6_pcbnotify(&udbtable, sa, 0,
296 		    (const struct sockaddr *)sa6_src, 0, cmd, cmdarg, notify);
297 	}
298 	return NULL;
299 }
300 
301 int
302 udp6_ctloutput(int op, struct socket *so, struct sockopt *sopt)
303 {
304 	int s;
305 	int error = 0;
306 	int family;
307 
308 	family = so->so_proto->pr_domain->dom_family;
309 
310 	s = splsoftnet();
311 	switch (family) {
312 #ifdef INET
313 	case PF_INET:
314 		if (sopt->sopt_level != IPPROTO_UDP) {
315 			error = ip_ctloutput(op, so, sopt);
316 			goto end;
317 		}
318 		break;
319 #endif
320 #ifdef INET6
321 	case PF_INET6:
322 		if (sopt->sopt_level != IPPROTO_UDP) {
323 			error = ip6_ctloutput(op, so, sopt);
324 			goto end;
325 		}
326 		break;
327 #endif
328 	default:
329 		error = EAFNOSUPPORT;
330 		goto end;
331 	}
332 	error = EINVAL;
333 
334 end:
335 	splx(s);
336 	return error;
337 }
338 
339 static void
340 udp6_sendup(struct mbuf *m, int off /* offset of data portion */,
341 	struct sockaddr *src, struct socket *so)
342 {
343 	struct mbuf *opts = NULL;
344 	struct mbuf *n;
345 	struct in6pcb *in6p = NULL;
346 
347 	if (!so)
348 		return;
349 	if (so->so_proto->pr_domain->dom_family != AF_INET6)
350 		return;
351 	in6p = sotoin6pcb(so);
352 
353 #if defined(IPSEC)
354 	/* check AH/ESP integrity. */
355 	if (ipsec_used && so != NULL && ipsec6_in_reject_so(m, so)) {
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->in6p_flags & IN6P_CONTROLOPTS
366 #ifdef SO_OTIMESTAMP
367 		    || in6p->in6p_socket->so_options & SO_OTIMESTAMP
368 #endif
369 		    || in6p->in6p_socket->so_options & SO_TIMESTAMP)) {
370 			struct ip6_hdr *ip6 = mtod(n, struct ip6_hdr *);
371 			ip6_savecontrol(in6p, &opts, ip6, n);
372 		}
373 
374 		m_adj(n, off);
375 		if (sbappendaddr(&so->so_rcv, src, n, opts) == 0) {
376 			m_freem(n);
377 			if (opts)
378 				m_freem(opts);
379 			so->so_rcv.sb_overflowed++;
380 			UDP6_STATINC(UDP6_STAT_FULLSOCK);
381 		} else
382 			sorwakeup(so);
383 	}
384 }
385 
386 int
387 udp6_realinput(int af, struct sockaddr_in6 *src, struct sockaddr_in6 *dst,
388 	struct mbuf *m, int off)
389 {
390 	u_int16_t sport, dport;
391 	int rcvcnt;
392 	struct in6_addr src6, *dst6;
393 	const struct in_addr *dst4;
394 	struct inpcb_hdr *inph;
395 	struct in6pcb *in6p;
396 
397 	rcvcnt = 0;
398 	off += sizeof(struct udphdr);	/* now, offset of payload */
399 
400 	if (af != AF_INET && af != AF_INET6)
401 		goto bad;
402 	if (src->sin6_family != AF_INET6 || dst->sin6_family != AF_INET6)
403 		goto bad;
404 
405 	src6 = src->sin6_addr;
406 	if (sa6_recoverscope(src) != 0) {
407 		/* XXX: should be impossible. */
408 		goto bad;
409 	}
410 	sport = src->sin6_port;
411 
412 	dport = dst->sin6_port;
413 	dst4 = (struct in_addr *)&dst->sin6_addr.s6_addr[12];
414 	dst6 = &dst->sin6_addr;
415 
416 	if (IN6_IS_ADDR_MULTICAST(dst6) ||
417 	    (af == AF_INET && IN_MULTICAST(dst4->s_addr))) {
418 		/*
419 		 * Deliver a multicast or broadcast datagram to *all* sockets
420 		 * for which the local and remote addresses and ports match
421 		 * those of the incoming datagram.  This allows more than
422 		 * one process to receive multi/broadcasts on the same port.
423 		 * (This really ought to be done for unicast datagrams as
424 		 * well, but that would cause problems with existing
425 		 * applications that open both address-specific sockets and
426 		 * a wildcard socket listening to the same port -- they would
427 		 * end up receiving duplicates of every unicast datagram.
428 		 * Those applications open the multiple sockets to overcome an
429 		 * inadequacy of the UDP socket interface, but for backwards
430 		 * compatibility we avoid the problem here rather than
431 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
432 		 */
433 
434 		/*
435 		 * KAME note: traditionally we dropped udpiphdr from mbuf here.
436 		 * we need udpiphdr for IPsec processing so we do that later.
437 		 */
438 		/*
439 		 * Locate pcb(s) for datagram.
440 		 */
441 		TAILQ_FOREACH(inph, &udbtable.inpt_queue, inph_queue) {
442 			in6p = (struct in6pcb *)inph;
443 			if (in6p->in6p_af != AF_INET6)
444 				continue;
445 
446 			if (in6p->in6p_lport != dport)
447 				continue;
448 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
449 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr,
450 				    dst6))
451 					continue;
452 			} else {
453 				if (IN6_IS_ADDR_V4MAPPED(dst6) &&
454 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
455 					continue;
456 			}
457 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
458 				if (!IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr,
459 				    &src6) || in6p->in6p_fport != sport)
460 					continue;
461 			} else {
462 				if (IN6_IS_ADDR_V4MAPPED(&src6) &&
463 				    (in6p->in6p_flags & IN6P_IPV6_V6ONLY))
464 					continue;
465 			}
466 
467 			udp6_sendup(m, off, (struct sockaddr *)src,
468 				in6p->in6p_socket);
469 			rcvcnt++;
470 
471 			/*
472 			 * Don't look for additional matches if this one does
473 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
474 			 * socket options set.  This heuristic avoids searching
475 			 * through all pcbs in the common case of a non-shared
476 			 * port.  It assumes that an application will never
477 			 * clear these options after setting them.
478 			 */
479 			if ((in6p->in6p_socket->so_options &
480 			    (SO_REUSEPORT|SO_REUSEADDR)) == 0)
481 				break;
482 		}
483 	} else {
484 		/*
485 		 * Locate pcb for datagram.
486 		 */
487 		in6p = in6_pcblookup_connect(&udbtable, &src6, sport, dst6,
488 					     dport, 0, 0);
489 		if (in6p == 0) {
490 			UDP_STATINC(UDP_STAT_PCBHASHMISS);
491 			in6p = in6_pcblookup_bind(&udbtable, dst6, dport, 0);
492 			if (in6p == 0)
493 				return rcvcnt;
494 		}
495 
496 		udp6_sendup(m, off, (struct sockaddr *)src, in6p->in6p_socket);
497 		rcvcnt++;
498 	}
499 
500 bad:
501 	return rcvcnt;
502 }
503 
504 int
505 udp6_input_checksum(struct mbuf *m, const struct udphdr *uh, int off, int len)
506 {
507 
508 	/*
509 	 * XXX it's better to record and check if this mbuf is
510 	 * already checked.
511 	 */
512 
513 	if (__predict_false((m->m_flags & M_LOOP) && !udp_do_loopback_cksum)) {
514 		goto good;
515 	}
516 	if (uh->uh_sum == 0) {
517 		UDP6_STATINC(UDP6_STAT_NOSUM);
518 		goto bad;
519 	}
520 
521 	switch (m->m_pkthdr.csum_flags &
522 	    ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_UDPv6) |
523 	    M_CSUM_TCP_UDP_BAD | M_CSUM_DATA)) {
524 	case M_CSUM_UDPv6|M_CSUM_TCP_UDP_BAD:
525 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_bad);
526 		UDP6_STATINC(UDP6_STAT_BADSUM);
527 		goto bad;
528 
529 #if 0 /* notyet */
530 	case M_CSUM_UDPv6|M_CSUM_DATA:
531 #endif
532 
533 	case M_CSUM_UDPv6:
534 		/* Checksum was okay. */
535 		UDP_CSUM_COUNTER_INCR(&udp6_hwcsum_ok);
536 		break;
537 
538 	default:
539 		/*
540 		 * Need to compute it ourselves.  Maybe skip checksum
541 		 * on loopback interfaces.
542 		 */
543 		UDP_CSUM_COUNTER_INCR(&udp6_swcsum);
544 		if (in6_cksum(m, IPPROTO_UDP, off, len) != 0) {
545 			UDP6_STATINC(UDP6_STAT_BADSUM);
546 			goto bad;
547 		}
548 	}
549 
550 good:
551 	return 0;
552 bad:
553 	return -1;
554 }
555 
556 int
557 udp6_input(struct mbuf **mp, int *offp, int proto)
558 {
559 	struct mbuf *m = *mp;
560 	int off = *offp;
561 	struct sockaddr_in6 src, dst;
562 	struct ip6_hdr *ip6;
563 	struct udphdr *uh;
564 	u_int32_t plen, ulen;
565 
566 	ip6 = mtod(m, struct ip6_hdr *);
567 
568 #if defined(NFAITH) && 0 < NFAITH
569 	if (faithprefix(&ip6->ip6_dst)) {
570 		/* send icmp6 host unreach? */
571 		m_freem(m);
572 		return IPPROTO_DONE;
573 	}
574 #endif
575 
576 	UDP6_STATINC(UDP6_STAT_IPACKETS);
577 
578 	/* check for jumbogram is done in ip6_input.  we can trust pkthdr.len */
579 	plen = m->m_pkthdr.len - off;
580 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(struct udphdr));
581 	if (uh == NULL) {
582 		IP6_STATINC(IP6_STAT_TOOSHORT);
583 		return IPPROTO_DONE;
584 	}
585 	KASSERT(UDP_HDR_ALIGNED_P(uh));
586 	ulen = ntohs((u_short)uh->uh_ulen);
587 	/*
588 	 * RFC2675 section 4: jumbograms will have 0 in the UDP header field,
589 	 * iff payload length > 0xffff.
590 	 */
591 	if (ulen == 0 && plen > 0xffff)
592 		ulen = plen;
593 
594 	if (plen != ulen) {
595 		UDP6_STATINC(UDP6_STAT_BADLEN);
596 		goto bad;
597 	}
598 
599 	/* destination port of 0 is illegal, based on RFC768. */
600 	if (uh->uh_dport == 0)
601 		goto bad;
602 
603 	/* Be proactive about malicious use of IPv4 mapped address */
604 	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
605 	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
606 		/* XXX stat */
607 		goto bad;
608 	}
609 
610 	/*
611 	 * Checksum extended UDP header and data.  Maybe skip checksum
612 	 * on loopback interfaces.
613 	 */
614 	if (udp6_input_checksum(m, uh, off, ulen))
615 		goto bad;
616 
617 	/*
618 	 * Construct source and dst sockaddrs.
619 	 */
620 	memset(&src, 0, sizeof(src));
621 	src.sin6_family = AF_INET6;
622 	src.sin6_len = sizeof(struct sockaddr_in6);
623 	src.sin6_addr = ip6->ip6_src;
624 	src.sin6_port = uh->uh_sport;
625 	memset(&dst, 0, sizeof(dst));
626 	dst.sin6_family = AF_INET6;
627 	dst.sin6_len = sizeof(struct sockaddr_in6);
628 	dst.sin6_addr = ip6->ip6_dst;
629 	dst.sin6_port = uh->uh_dport;
630 
631 	if (udp6_realinput(AF_INET6, &src, &dst, m, off) == 0) {
632 		if (m->m_flags & M_MCAST) {
633 			UDP6_STATINC(UDP6_STAT_NOPORTMCAST);
634 			goto bad;
635 		}
636 		UDP6_STATINC(UDP6_STAT_NOPORT);
637 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
638 		m = NULL;
639 	}
640 
641 bad:
642 	if (m)
643 		m_freem(m);
644 	return IPPROTO_DONE;
645 }
646 
647 static int
648 udp6_attach(struct socket *so, int proto)
649 {
650 	struct in6pcb *in6p;
651 	int s, error;
652 
653 	KASSERT(sotoin6pcb(so) == NULL);
654 	sosetlock(so);
655 
656 	/*
657 	 * MAPPED_ADDR implementation spec:
658 	 *  Always attach for IPv6, and only when necessary for IPv4.
659 	 */
660 	s = splsoftnet();
661 	error = in6_pcballoc(so, &udbtable);
662 	splx(s);
663 	if (error) {
664 		return error;
665 	}
666 	error = soreserve(so, udp6_sendspace, udp6_recvspace);
667 	if (error) {
668 		return error;
669 	}
670 	in6p = sotoin6pcb(so);
671 	in6p->in6p_cksum = -1;	/* just to be sure */
672 
673 	KASSERT(solocked(so));
674 	return 0;
675 }
676 
677 static void
678 udp6_detach(struct socket *so)
679 {
680 	struct in6pcb *in6p = sotoin6pcb(so);
681 	int s;
682 
683 	KASSERT(solocked(so));
684 	KASSERT(in6p != NULL);
685 
686 	s = splsoftnet();
687 	in6_pcbdetach(in6p);
688 	splx(s);
689 }
690 
691 static int
692 udp6_accept(struct socket *so, struct sockaddr *nam)
693 {
694 	KASSERT(solocked(so));
695 
696 	return EOPNOTSUPP;
697 }
698 
699 static int
700 udp6_bind(struct socket *so, struct sockaddr *nam, struct lwp *l)
701 {
702 	struct in6pcb *in6p = sotoin6pcb(so);
703 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
704 	int error = 0;
705 	int s;
706 
707 	KASSERT(solocked(so));
708 	KASSERT(in6p != NULL);
709 
710 	s = splsoftnet();
711 	error = in6_pcbbind(in6p, sin6, l);
712 	splx(s);
713 	return error;
714 }
715 
716 static int
717 udp6_listen(struct socket *so, struct lwp *l)
718 {
719 	KASSERT(solocked(so));
720 
721 	return EOPNOTSUPP;
722 }
723 
724 static int
725 udp6_connect(struct socket *so, struct sockaddr *nam, struct lwp *l)
726 {
727 	struct in6pcb *in6p = sotoin6pcb(so);
728 	int error = 0;
729 	int s;
730 
731 	KASSERT(solocked(so));
732 	KASSERT(in6p != NULL);
733 
734 	if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr))
735 		return EISCONN;
736 	s = splsoftnet();
737 	error = in6_pcbconnect(in6p, (struct sockaddr_in6 *)nam, l);
738 	splx(s);
739 	if (error == 0)
740 		soisconnected(so);
741 
742 	return error;
743 }
744 
745 static int
746 udp6_connect2(struct socket *so, struct socket *so2)
747 {
748 	KASSERT(solocked(so));
749 
750 	return EOPNOTSUPP;
751 }
752 
753 static int
754 udp6_disconnect(struct socket *so)
755 {
756 	struct in6pcb *in6p = sotoin6pcb(so);
757 	int s;
758 
759 	KASSERT(solocked(so));
760 	KASSERT(in6p != NULL);
761 
762 	if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr))
763 		return ENOTCONN;
764 
765 	s = splsoftnet();
766 	in6_pcbdisconnect(in6p);
767 	memset((void *)&in6p->in6p_laddr, 0, sizeof(in6p->in6p_laddr));
768 	splx(s);
769 
770 	so->so_state &= ~SS_ISCONNECTED;	/* XXX */
771 	in6_pcbstate(in6p, IN6P_BOUND);		/* XXX */
772 	return 0;
773 }
774 
775 static int
776 udp6_shutdown(struct socket *so)
777 {
778 	int s;
779 
780 	s = splsoftnet();
781 	socantsendmore(so);
782 	splx(s);
783 
784 	return 0;
785 }
786 
787 static int
788 udp6_abort(struct socket *so)
789 {
790 	int s;
791 
792 	KASSERT(solocked(so));
793 	KASSERT(sotoin6pcb(so) != NULL);
794 
795 	s = splsoftnet();
796 	soisdisconnected(so);
797 	in6_pcbdetach(sotoin6pcb(so));
798 	splx(s);
799 
800 	return 0;
801 }
802 
803 static int
804 udp6_ioctl(struct socket *so, u_long cmd, void *addr6, struct ifnet *ifp)
805 {
806 	/*
807 	 * MAPPED_ADDR implementation info:
808 	 *  Mapped addr support for PRU_CONTROL is not necessary.
809 	 *  Because typical user of PRU_CONTROL is such as ifconfig,
810 	 *  and they don't associate any addr to their socket.  Then
811 	 *  socket family is only hint about the PRU_CONTROL'ed address
812 	 *  family, especially when getting addrs from kernel.
813 	 *  So AF_INET socket need to be used to control AF_INET addrs,
814 	 *  and AF_INET6 socket for AF_INET6 addrs.
815 	 */
816 	return in6_control(so, cmd, addr6, ifp);
817 }
818 
819 static int
820 udp6_stat(struct socket *so, struct stat *ub)
821 {
822 	KASSERT(solocked(so));
823 
824 	/* stat: don't bother with a blocksize */
825 	return 0;
826 }
827 
828 static int
829 udp6_peeraddr(struct socket *so, struct sockaddr *nam)
830 {
831 	KASSERT(solocked(so));
832 	KASSERT(sotoin6pcb(so) != NULL);
833 	KASSERT(nam != NULL);
834 
835 	in6_setpeeraddr(sotoin6pcb(so), (struct sockaddr_in6 *)nam);
836 	return 0;
837 }
838 
839 static int
840 udp6_sockaddr(struct socket *so, struct sockaddr *nam)
841 {
842 	KASSERT(solocked(so));
843 	KASSERT(sotoin6pcb(so) != NULL);
844 	KASSERT(nam != NULL);
845 
846 	in6_setsockaddr(sotoin6pcb(so), (struct sockaddr_in6 *)nam);
847 	return 0;
848 }
849 
850 static int
851 udp6_rcvd(struct socket *so, int flags, struct lwp *l)
852 {
853 	KASSERT(solocked(so));
854 
855 	return EOPNOTSUPP;
856 }
857 
858 static int
859 udp6_recvoob(struct socket *so, struct mbuf *m, int flags)
860 {
861 	KASSERT(solocked(so));
862 
863 	return EOPNOTSUPP;
864 }
865 
866 static int
867 udp6_send(struct socket *so, struct mbuf *m, struct sockaddr *nam,
868     struct mbuf *control, struct lwp *l)
869 {
870 	struct in6pcb *in6p = sotoin6pcb(so);
871 	int error = 0;
872 	int s;
873 
874 	KASSERT(solocked(so));
875 	KASSERT(in6p != NULL);
876 	KASSERT(m != NULL);
877 
878 	s = splsoftnet();
879 	error = udp6_output(in6p, m, (struct sockaddr_in6 *)nam, control, l);
880 	splx(s);
881 
882 	return error;
883 }
884 
885 static int
886 udp6_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
887 {
888 	KASSERT(solocked(so));
889 
890 	if (m)
891 		m_freem(m);
892 	if (control)
893 		m_freem(control);
894 
895 	return EOPNOTSUPP;
896 }
897 
898 static int
899 udp6_purgeif(struct socket *so, struct ifnet *ifp)
900 {
901 
902 	mutex_enter(softnet_lock);
903 	in6_pcbpurgeif0(&udbtable, ifp);
904 	in6_purgeif(ifp);
905 	in6_pcbpurgeif(&udbtable, ifp);
906 	mutex_exit(softnet_lock);
907 
908 	return 0;
909 }
910 
911 static int
912 sysctl_net_inet6_udp6_stats(SYSCTLFN_ARGS)
913 {
914 
915 	return (NETSTAT_SYSCTL(udp6stat_percpu, UDP6_NSTATS));
916 }
917 
918 static void
919 sysctl_net_inet6_udp6_setup(struct sysctllog **clog)
920 {
921 
922 	sysctl_createv(clog, 0, NULL, NULL,
923 		       CTLFLAG_PERMANENT,
924 		       CTLTYPE_NODE, "inet6", NULL,
925 		       NULL, 0, NULL, 0,
926 		       CTL_NET, PF_INET6, CTL_EOL);
927 	sysctl_createv(clog, 0, NULL, NULL,
928 		       CTLFLAG_PERMANENT,
929 		       CTLTYPE_NODE, "udp6",
930 		       SYSCTL_DESCR("UDPv6 related settings"),
931 		       NULL, 0, NULL, 0,
932 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_EOL);
933 
934 	sysctl_createv(clog, 0, NULL, NULL,
935 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
936 		       CTLTYPE_INT, "sendspace",
937 		       SYSCTL_DESCR("Default UDP send buffer size"),
938 		       NULL, 0, &udp6_sendspace, 0,
939 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_SENDSPACE,
940 		       CTL_EOL);
941 	sysctl_createv(clog, 0, NULL, NULL,
942 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
943 		       CTLTYPE_INT, "recvspace",
944 		       SYSCTL_DESCR("Default UDP receive buffer size"),
945 		       NULL, 0, &udp6_recvspace, 0,
946 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_RECVSPACE,
947 		       CTL_EOL);
948 	sysctl_createv(clog, 0, NULL, NULL,
949 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
950 		       CTLTYPE_INT, "do_loopback_cksum",
951 		       SYSCTL_DESCR("Perform UDP checksum on loopback"),
952 		       NULL, 0, &udp_do_loopback_cksum, 0,
953 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_LOOPBACKCKSUM,
954 		       CTL_EOL);
955 	sysctl_createv(clog, 0, NULL, NULL,
956 		       CTLFLAG_PERMANENT,
957 		       CTLTYPE_STRUCT, "pcblist",
958 		       SYSCTL_DESCR("UDP protocol control block list"),
959 		       sysctl_inpcblist, 0, &udbtable, 0,
960 		       CTL_NET, PF_INET6, IPPROTO_UDP, CTL_CREATE,
961 		       CTL_EOL);
962 	sysctl_createv(clog, 0, NULL, NULL,
963 		       CTLFLAG_PERMANENT,
964 		       CTLTYPE_STRUCT, "stats",
965 		       SYSCTL_DESCR("UDPv6 statistics"),
966 		       sysctl_net_inet6_udp6_stats, 0, NULL, 0,
967 		       CTL_NET, PF_INET6, IPPROTO_UDP, UDP6CTL_STATS,
968 		       CTL_EOL);
969 }
970 
971 void
972 udp6_statinc(u_int stat)
973 {
974 
975 	KASSERT(stat < UDP6_NSTATS);
976 	UDP6_STATINC(stat);
977 }
978 
979 PR_WRAP_USRREQS(udp6)
980 #define	udp6_attach	udp6_attach_wrapper
981 #define	udp6_detach	udp6_detach_wrapper
982 #define	udp6_accept	udp6_accept_wrapper
983 #define	udp6_bind	udp6_bind_wrapper
984 #define	udp6_listen	udp6_listen_wrapper
985 #define	udp6_connect	udp6_connect_wrapper
986 #define	udp6_connect2	udp6_connect2_wrapper
987 #define	udp6_disconnect	udp6_disconnect_wrapper
988 #define	udp6_shutdown	udp6_shutdown_wrapper
989 #define	udp6_abort	udp6_abort_wrapper
990 #define	udp6_ioctl	udp6_ioctl_wrapper
991 #define	udp6_stat	udp6_stat_wrapper
992 #define	udp6_peeraddr	udp6_peeraddr_wrapper
993 #define	udp6_sockaddr	udp6_sockaddr_wrapper
994 #define	udp6_rcvd	udp6_rcvd_wrapper
995 #define	udp6_recvoob	udp6_recvoob_wrapper
996 #define	udp6_send	udp6_send_wrapper
997 #define	udp6_sendoob	udp6_sendoob_wrapper
998 #define	udp6_purgeif	udp6_purgeif_wrapper
999 
1000 const struct pr_usrreqs udp6_usrreqs = {
1001 	.pr_attach	= udp6_attach,
1002 	.pr_detach	= udp6_detach,
1003 	.pr_accept	= udp6_accept,
1004 	.pr_bind	= udp6_bind,
1005 	.pr_listen	= udp6_listen,
1006 	.pr_connect	= udp6_connect,
1007 	.pr_connect2	= udp6_connect2,
1008 	.pr_disconnect	= udp6_disconnect,
1009 	.pr_shutdown	= udp6_shutdown,
1010 	.pr_abort	= udp6_abort,
1011 	.pr_ioctl	= udp6_ioctl,
1012 	.pr_stat	= udp6_stat,
1013 	.pr_peeraddr	= udp6_peeraddr,
1014 	.pr_sockaddr	= udp6_sockaddr,
1015 	.pr_rcvd	= udp6_rcvd,
1016 	.pr_recvoob	= udp6_recvoob,
1017 	.pr_send	= udp6_send,
1018 	.pr_sendoob	= udp6_sendoob,
1019 	.pr_purgeif	= udp6_purgeif,
1020 };
1021