xref: /xnu-10002.61.3/bsd/netinet6/udp6_usrreq.c (revision 0f4c859e951fba394238ab619495c4e1d54d0f34)
1 /*
2  * Copyright (c) 2000-2022 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 /*	$FreeBSD: src/sys/netinet6/udp6_usrreq.c,v 1.6.2.6 2001/07/29 19:32:40 ume Exp $	*/
30 /*	$KAME: udp6_usrreq.c,v 1.27 2001/05/21 05:45:10 jinmei Exp $	*/
31 
32 /*
33  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the project nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  */
60 
61 /*
62  * Copyright (c) 1982, 1986, 1989, 1993
63  *	The Regents of the University of California.  All rights reserved.
64  *
65  * Redistribution and use in source and binary forms, with or without
66  * modification, are permitted provided that the following conditions
67  * are met:
68  * 1. Redistributions of source code must retain the above copyright
69  *    notice, this list of conditions and the following disclaimer.
70  * 2. Redistributions in binary form must reproduce the above copyright
71  *    notice, this list of conditions and the following disclaimer in the
72  *    documentation and/or other materials provided with the distribution.
73  * 3. All advertising materials mentioning features or use of this software
74  *    must display the following acknowledgement:
75  *	This product includes software developed by the University of
76  *	California, Berkeley and its contributors.
77  * 4. Neither the name of the University nor the names of its contributors
78  *    may be used to endorse or promote products derived from this software
79  *    without specific prior written permission.
80  *
81  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
82  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
83  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
84  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
85  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
86  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
87  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
88  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
89  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
90  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
91  * SUCH DAMAGE.
92  *
93  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
94  */
95 #include <sys/kernel.h>
96 #include <sys/malloc.h>
97 #include <sys/mbuf.h>
98 #include <sys/param.h>
99 #include <sys/protosw.h>
100 #include <sys/socket.h>
101 #include <sys/socketvar.h>
102 #include <sys/sysctl.h>
103 #include <sys/errno.h>
104 #include <sys/stat.h>
105 #include <sys/systm.h>
106 #include <sys/syslog.h>
107 #include <sys/proc.h>
108 #include <sys/kauth.h>
109 
110 #include <net/if.h>
111 #include <net/route.h>
112 #include <net/if_types.h>
113 #include <net/ntstat.h>
114 #include <net/dlil.h>
115 #include <net/net_api_stats.h>
116 
117 #include <netinet/in.h>
118 #include <netinet/in_systm.h>
119 #include <netinet/ip.h>
120 #include <netinet/in_pcb.h>
121 #include <netinet/in_var.h>
122 #include <netinet/ip_var.h>
123 #include <netinet/udp.h>
124 #include <netinet/udp_var.h>
125 #include <netinet/udp_log.h>
126 
127 #include <netinet/ip6.h>
128 #include <netinet6/ip6_var.h>
129 #include <netinet6/in6_pcb.h>
130 #include <netinet/icmp6.h>
131 #include <netinet6/udp6_var.h>
132 #include <netinet6/ip6protosw.h>
133 
134 #if IPSEC
135 #include <netinet6/ipsec.h>
136 #include <netinet6/ipsec6.h>
137 #include <netinet6/esp6.h>
138 #include <netkey/key.h>
139 extern int ipsec_bypass;
140 extern int esp_udp_encap_port;
141 #endif /* IPSEC */
142 
143 #if NECP
144 #include <net/necp.h>
145 #endif /* NECP */
146 
147 #if FLOW_DIVERT
148 #include <netinet/flow_divert.h>
149 #endif /* FLOW_DIVERT */
150 
151 #if CONTENT_FILTER
152 #include <net/content_filter.h>
153 #endif /* CONTENT_FILTER */
154 
155 #if SKYWALK
156 #include <skywalk/core/skywalk_var.h>
157 #endif /* SKYWALK */
158 
159 /*
160  * UDP protocol inplementation.
161  * Per RFC 768, August, 1980.
162  */
163 
164 static int udp6_abort(struct socket *);
165 static int udp6_attach(struct socket *, int, struct proc *);
166 static int udp6_bind(struct socket *, struct sockaddr *, struct proc *);
167 static int udp6_connectx(struct socket *, struct sockaddr *,
168     struct sockaddr *, struct proc *, uint32_t, sae_associd_t,
169     sae_connid_t *, uint32_t, void *, uint32_t, struct uio *, user_ssize_t *);
170 static  int udp6_detach(struct socket *);
171 static int udp6_disconnect(struct socket *);
172 static int udp6_disconnectx(struct socket *, sae_associd_t, sae_connid_t);
173 static int udp6_send(struct socket *, int, struct mbuf *, struct sockaddr *,
174     struct mbuf *, struct proc *);
175 static void udp6_append(struct inpcb *, struct ip6_hdr *,
176     struct sockaddr_in6 *, struct mbuf *, int, struct ifnet *);
177 static int udp6_input_checksum(struct mbuf *, struct udphdr *, int, int);
178 static int udp6_defunct(struct socket *);
179 
180 struct pr_usrreqs udp6_usrreqs = {
181 	.pru_abort =            udp6_abort,
182 	.pru_attach =           udp6_attach,
183 	.pru_bind =             udp6_bind,
184 	.pru_connect =          udp6_connect,
185 	.pru_connectx =         udp6_connectx,
186 	.pru_control =          in6_control,
187 	.pru_detach =           udp6_detach,
188 	.pru_disconnect =       udp6_disconnect,
189 	.pru_disconnectx =      udp6_disconnectx,
190 	.pru_peeraddr =         in6_mapped_peeraddr,
191 	.pru_send =             udp6_send,
192 	.pru_shutdown =         udp_shutdown,
193 	.pru_sockaddr =         in6_mapped_sockaddr,
194 	.pru_sosend =           sosend,
195 	.pru_soreceive =        soreceive,
196 	.pru_defunct =          udp6_defunct,
197 };
198 
199 /*
200  * subroutine of udp6_input(), mainly for source code readability.
201  */
202 static void
udp6_append(struct inpcb * last,struct ip6_hdr * ip6,struct sockaddr_in6 * udp_in6,struct mbuf * n,int off,struct ifnet * ifp)203 udp6_append(struct inpcb *last, struct ip6_hdr *ip6,
204     struct sockaddr_in6 *udp_in6, struct mbuf *n, int off, struct ifnet *ifp)
205 {
206 #pragma unused(ip6)
207 	struct  mbuf *opts = NULL;
208 	int ret = 0;
209 	boolean_t cell = IFNET_IS_CELLULAR(ifp);
210 	boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp));
211 	boolean_t wired = (!wifi && IFNET_IS_WIRED(ifp));
212 
213 	if ((last->in6p_flags & INP_CONTROLOPTS) != 0 ||
214 	    SOFLOW_ENABLED(last->in6p_socket) ||
215 	    SO_RECV_CONTROL_OPTS(last->in6p_socket)) {
216 		ret = ip6_savecontrol(last, n, &opts);
217 		if (ret != 0) {
218 			m_freem(n);
219 			m_freem(opts);
220 			return;
221 		}
222 	}
223 	m_adj(n, off);
224 	if (nstat_collect) {
225 		INP_ADD_STAT(last, cell, wifi, wired, rxpackets, 1);
226 		INP_ADD_STAT(last, cell, wifi, wired, rxbytes, n->m_pkthdr.len);
227 		inp_set_activity_bitmap(last);
228 	}
229 	so_recv_data_stat(last->in6p_socket, n, 0);
230 	if (sbappendaddr(&last->in6p_socket->so_rcv,
231 	    (struct sockaddr *)udp_in6, n, opts, NULL) == 0) {
232 		udpstat.udps_fullsock++;
233 	} else {
234 		sorwakeup(last->in6p_socket);
235 	}
236 }
237 
238 int
udp6_input(struct mbuf ** mp,int * offp,int proto)239 udp6_input(struct mbuf **mp, int *offp, int proto)
240 {
241 #pragma unused(proto)
242 	struct mbuf *m = *mp;
243 	struct ifnet *ifp;
244 	struct ip6_hdr *ip6;
245 	struct udphdr *uh;
246 	struct inpcb *in6p;
247 	struct  mbuf *opts = NULL;
248 	int off = *offp;
249 	int plen, ulen, ret = 0;
250 	boolean_t cell, wifi, wired;
251 	struct sockaddr_in6 udp_in6;
252 	struct inpcbinfo *pcbinfo = &udbinfo;
253 	struct sockaddr_in6 fromsa;
254 	u_int16_t pf_tag = 0;
255 	boolean_t is_wake_pkt = false;
256 
257 	IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), return IPPROTO_DONE);
258 
259 	/* Expect 32-bit aligned data pointer on strict-align platforms */
260 	MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
261 
262 	ifp = m->m_pkthdr.rcvif;
263 	ip6 = mtod(m, struct ip6_hdr *);
264 	cell = IFNET_IS_CELLULAR(ifp);
265 	wifi = (!cell && IFNET_IS_WIFI(ifp));
266 	wired = (!wifi && IFNET_IS_WIRED(ifp));
267 
268 	if (m->m_flags & M_PKTHDR) {
269 		pf_tag = m_pftag(m)->pftag_tag;
270 		if (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT) {
271 			is_wake_pkt = true;
272 		}
273 	}
274 
275 	udpstat.udps_ipackets++;
276 
277 	plen = ntohs(ip6->ip6_plen) - off + sizeof(*ip6);
278 	uh = (struct udphdr *)(void *)((caddr_t)ip6 + off);
279 	ulen = ntohs((u_short)uh->uh_ulen);
280 
281 	if (plen != ulen) {
282 		udpstat.udps_badlen++;
283 		IF_UDP_STATINC(ifp, badlength);
284 		goto bad;
285 	}
286 
287 	/* destination port of 0 is illegal, based on RFC768. */
288 	if (uh->uh_dport == 0) {
289 		IF_UDP_STATINC(ifp, port0);
290 		goto bad;
291 	}
292 
293 	/*
294 	 * Checksum extended UDP header and data.
295 	 */
296 	if (udp6_input_checksum(m, uh, off, ulen)) {
297 		goto bad;
298 	}
299 
300 	/*
301 	 * Construct sockaddr format source address.
302 	 */
303 	init_sin6(&fromsa, m);
304 	fromsa.sin6_port = uh->uh_sport;
305 
306 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
307 		int reuse_sock = 0, mcast_delivered = 0;
308 		struct ip6_moptions *imo;
309 
310 		/*
311 		 * Deliver a multicast datagram to all sockets
312 		 * for which the local and remote addresses and ports match
313 		 * those of the incoming datagram.  This allows more than
314 		 * one process to receive multicasts on the same port.
315 		 * (This really ought to be done for unicast datagrams as
316 		 * well, but that would cause problems with existing
317 		 * applications that open both address-specific sockets and
318 		 * a wildcard socket listening to the same port -- they would
319 		 * end up receiving duplicates of every unicast datagram.
320 		 * Those applications open the multiple sockets to overcome an
321 		 * inadequacy of the UDP socket interface, but for backwards
322 		 * compatibility we avoid the problem here rather than
323 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
324 		 */
325 
326 		/*
327 		 * In a case that laddr should be set to the link-local
328 		 * address (this happens in RIPng), the multicast address
329 		 * specified in the received packet does not match with
330 		 * laddr. To cure this situation, the matching is relaxed
331 		 * if the receiving interface is the same as one specified
332 		 * in the socket and if the destination multicast address
333 		 * matches one of the multicast groups specified in the socket.
334 		 */
335 
336 		/*
337 		 * Construct sockaddr format source address.
338 		 */
339 		init_sin6(&udp_in6, m); /* general init */
340 		udp_in6.sin6_port = uh->uh_sport;
341 		/*
342 		 * KAME note: usually we drop udphdr from mbuf here.
343 		 * We need udphdr for IPsec processing so we do that later.
344 		 */
345 
346 		/*
347 		 * Locate pcb(s) for datagram.
348 		 * (Algorithm copied from raw_intr().)
349 		 */
350 		lck_rw_lock_shared(&pcbinfo->ipi_lock);
351 
352 		LIST_FOREACH(in6p, &udb, inp_list) {
353 #if IPSEC
354 			int skipit;
355 #endif /* IPSEC */
356 
357 			if ((in6p->inp_vflag & INP_IPV6) == 0) {
358 				continue;
359 			}
360 
361 			if (inp_restricted_recv(in6p, ifp)) {
362 				continue;
363 			}
364 			/*
365 			 * Skip unbound sockets before taking the lock on the socket as
366 			 * the test with the destination port in the header will fail
367 			 */
368 			if (in6p->in6p_lport == 0) {
369 				continue;
370 			}
371 
372 			if (in_pcb_checkstate(in6p, WNT_ACQUIRE, 0) ==
373 			    WNT_STOPUSING) {
374 				continue;
375 			}
376 
377 			udp_lock(in6p->in6p_socket, 1, 0);
378 
379 			if (in_pcb_checkstate(in6p, WNT_RELEASE, 1) ==
380 			    WNT_STOPUSING) {
381 				udp_unlock(in6p->in6p_socket, 1, 0);
382 				continue;
383 			}
384 			if (in6p->in6p_lport != uh->uh_dport) {
385 				udp_unlock(in6p->in6p_socket, 1, 0);
386 				continue;
387 			}
388 
389 			/*
390 			 * Handle socket delivery policy for any-source
391 			 * and source-specific multicast. [RFC3678]
392 			 */
393 			imo = in6p->in6p_moptions;
394 			if (imo && IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
395 				struct sockaddr_in6 mcaddr;
396 				int blocked;
397 
398 				IM6O_LOCK(imo);
399 				bzero(&mcaddr, sizeof(struct sockaddr_in6));
400 				mcaddr.sin6_len = sizeof(struct sockaddr_in6);
401 				mcaddr.sin6_family = AF_INET6;
402 				mcaddr.sin6_addr = ip6->ip6_dst;
403 
404 				blocked = im6o_mc_filter(imo, ifp,
405 				    &mcaddr, &fromsa);
406 				IM6O_UNLOCK(imo);
407 				if (blocked != MCAST_PASS) {
408 					udp_unlock(in6p->in6p_socket, 1, 0);
409 					if (blocked == MCAST_NOTSMEMBER ||
410 					    blocked == MCAST_MUTED) {
411 						udpstat.udps_filtermcast++;
412 					}
413 					continue;
414 				}
415 			}
416 			if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
417 			    (!in6_are_addr_equal_scoped(&in6p->in6p_faddr,
418 			    &ip6->ip6_src, in6p->inp_fifscope, ifp->if_index) ||
419 			    in6p->in6p_fport != uh->uh_sport)) {
420 				udp_unlock(in6p->in6p_socket, 1, 0);
421 				continue;
422 			}
423 
424 			reuse_sock = in6p->inp_socket->so_options &
425 			    (SO_REUSEPORT | SO_REUSEADDR);
426 
427 #if NECP
428 			skipit = 0;
429 			if (!necp_socket_is_allowed_to_send_recv_v6(in6p,
430 			    uh->uh_dport, uh->uh_sport, &ip6->ip6_dst,
431 			    &ip6->ip6_src, ifp, pf_tag, NULL, NULL, NULL, NULL)) {
432 				/* do not inject data to pcb */
433 				skipit = 1;
434 			}
435 			if (skipit == 0)
436 #endif /* NECP */
437 			{
438 				struct mbuf *n = NULL;
439 				/*
440 				 * KAME NOTE: do not
441 				 * m_copy(m, offset, ...) below.
442 				 * sbappendaddr() expects M_PKTHDR,
443 				 * and m_copy() will copy M_PKTHDR
444 				 * only if offset is 0.
445 				 */
446 				if (reuse_sock) {
447 					n = m_copy(m, 0, M_COPYALL);
448 				}
449 				udp6_append(in6p, ip6, &udp_in6, m,
450 				    off + sizeof(struct udphdr), ifp);
451 				mcast_delivered++;
452 				m = n;
453 			}
454 			if (is_wake_pkt) {
455 				soevent(in6p->in6p_socket,
456 				    SO_FILT_HINT_LOCKED | SO_FILT_HINT_WAKE_PKT);
457 			}
458 			udp_unlock(in6p->in6p_socket, 1, 0);
459 
460 			/*
461 			 * Don't look for additional matches if this one does
462 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
463 			 * socket options set.  This heuristic avoids searching
464 			 * through all pcbs in the common case of a non-shared
465 			 * port.  It assumes that an application will never
466 			 * clear these options after setting them.
467 			 */
468 			if (reuse_sock == 0 || m == NULL) {
469 				break;
470 			}
471 
472 			/*
473 			 * Expect 32-bit aligned data pointer on strict-align
474 			 * platforms.
475 			 */
476 			MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
477 
478 			/*
479 			 * Recompute IP and UDP header pointers for new mbuf
480 			 */
481 			ip6 = mtod(m, struct ip6_hdr *);
482 			uh = (struct udphdr *)(void *)((caddr_t)ip6 + off);
483 		}
484 		lck_rw_done(&pcbinfo->ipi_lock);
485 
486 		if (mcast_delivered == 0) {
487 			/*
488 			 * No matching pcb found; discard datagram.
489 			 * (No need to send an ICMP Port Unreachable
490 			 * for a broadcast or multicast datgram.)
491 			 */
492 			udpstat.udps_noport++;
493 			udpstat.udps_noportmcast++;
494 			IF_UDP_STATINC(ifp, port_unreach);
495 			goto bad;
496 		}
497 
498 		/* free the extra copy of mbuf or skipped by NECP */
499 		if (m != NULL) {
500 			m_freem(m);
501 		}
502 		return IPPROTO_DONE;
503 	}
504 
505 #if IPSEC
506 	/*
507 	 * UDP to port 4500 with a payload where the first four bytes are
508 	 * not zero is a UDP encapsulated IPsec packet. Packets where
509 	 * the payload is one byte and that byte is 0xFF are NAT keepalive
510 	 * packets. Decapsulate the ESP packet and carry on with IPsec input
511 	 * or discard the NAT keep-alive.
512 	 */
513 	if (ipsec_bypass == 0 && (esp_udp_encap_port & 0xFFFF) != 0 &&
514 	    (uh->uh_dport == ntohs((u_short)esp_udp_encap_port) ||
515 	    uh->uh_sport == ntohs((u_short)esp_udp_encap_port))) {
516 		/*
517 		 * Check if ESP or keepalive:
518 		 *      1. If the destination port of the incoming packet is 4500.
519 		 *      2. If the source port of the incoming packet is 4500,
520 		 *         then check the SADB to match IP address and port.
521 		 */
522 		bool check_esp = true;
523 		if (uh->uh_dport != ntohs((u_short)esp_udp_encap_port)) {
524 			check_esp = key_checksa_present(AF_INET6, (caddr_t)&ip6->ip6_dst,
525 			    (caddr_t)&ip6->ip6_src, uh->uh_dport,
526 			    uh->uh_sport, ip6_input_getdstifscope(m), ip6_input_getsrcifscope(m));
527 		}
528 
529 		if (check_esp) {
530 			int payload_len = ulen - sizeof(struct udphdr) > 4 ? 4 :
531 			    ulen - sizeof(struct udphdr);
532 
533 			if (m->m_len < off + sizeof(struct udphdr) + payload_len) {
534 				if ((m = m_pullup(m, off + sizeof(struct udphdr) +
535 				    payload_len)) == NULL) {
536 					udpstat.udps_hdrops++;
537 					goto bad;
538 				}
539 				/*
540 				 * Expect 32-bit aligned data pointer on strict-align
541 				 * platforms.
542 				 */
543 				MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
544 
545 				ip6 = mtod(m, struct ip6_hdr *);
546 				uh = (struct udphdr *)(void *)((caddr_t)ip6 + off);
547 			}
548 			/* Check for NAT keepalive packet */
549 			if (payload_len == 1 && *(u_int8_t*)
550 			    ((caddr_t)uh + sizeof(struct udphdr)) == 0xFF) {
551 				goto bad;
552 			} else if (payload_len == 4 && *(u_int32_t*)(void *)
553 			    ((caddr_t)uh + sizeof(struct udphdr)) != 0) {
554 				/* UDP encapsulated IPsec packet to pass through NAT */
555 				/* preserve the udp header */
556 				*offp = off + sizeof(struct udphdr);
557 				return esp6_input(mp, offp, IPPROTO_UDP);
558 			}
559 		}
560 	}
561 #endif /* IPSEC */
562 
563 	/*
564 	 * Locate pcb for datagram.
565 	 */
566 	in6p = in6_pcblookup_hash(&udbinfo, &ip6->ip6_src, uh->uh_sport, ip6_input_getsrcifscope(m),
567 	    &ip6->ip6_dst, uh->uh_dport, ip6_input_getdstifscope(m), 1, m->m_pkthdr.rcvif);
568 	if (in6p == NULL) {
569 		IF_UDP_STATINC(ifp, port_unreach);
570 
571 		if (udp_log_in_vain) {
572 			char buf[INET6_ADDRSTRLEN];
573 
574 			strlcpy(buf, ip6_sprintf(&ip6->ip6_dst), sizeof(buf));
575 			if (udp_log_in_vain < 3) {
576 				log(LOG_INFO, "Connection attempt to UDP "
577 				    "%s:%d from %s:%d\n", buf,
578 				    ntohs(uh->uh_dport),
579 				    ip6_sprintf(&ip6->ip6_src),
580 				    ntohs(uh->uh_sport));
581 			} else if (!(m->m_flags & (M_BCAST | M_MCAST)) &&
582 			    !in6_are_addr_equal_scoped(&ip6->ip6_dst, &ip6->ip6_src, ip6_input_getdstifscope(m), ip6_input_getsrcifscope(m))) {
583 				log(LOG_INFO, "Connection attempt "
584 				    "to UDP %s:%d from %s:%d\n", buf,
585 				    ntohs(uh->uh_dport),
586 				    ip6_sprintf(&ip6->ip6_src),
587 				    ntohs(uh->uh_sport));
588 			}
589 		}
590 		udpstat.udps_noport++;
591 		if (m->m_flags & M_MCAST) {
592 			printf("UDP6: M_MCAST is set in a unicast packet.\n");
593 			udpstat.udps_noportmcast++;
594 			IF_UDP_STATINC(ifp, badmcast);
595 			goto bad;
596 		}
597 		icmp6_error(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
598 		return IPPROTO_DONE;
599 	}
600 
601 	/*
602 	 * Construct sockaddr format source address.
603 	 * Stuff source address and datagram in user buffer.
604 	 */
605 	udp_lock(in6p->in6p_socket, 1, 0);
606 
607 #if NECP
608 	if (!necp_socket_is_allowed_to_send_recv_v6(in6p, uh->uh_dport,
609 	    uh->uh_sport, &ip6->ip6_dst, &ip6->ip6_src, ifp, pf_tag, NULL, NULL, NULL, NULL)) {
610 		in_pcb_checkstate(in6p, WNT_RELEASE, 1);
611 		udp_unlock(in6p->in6p_socket, 1, 0);
612 		IF_UDP_STATINC(ifp, badipsec);
613 		goto bad;
614 	}
615 #endif /* NECP */
616 
617 	if (in_pcb_checkstate(in6p, WNT_RELEASE, 1) == WNT_STOPUSING) {
618 		udp_unlock(in6p->in6p_socket, 1, 0);
619 		IF_UDP_STATINC(ifp, cleanup);
620 		goto bad;
621 	}
622 
623 	init_sin6(&udp_in6, m); /* general init */
624 	udp_in6.sin6_port = uh->uh_sport;
625 	if ((in6p->in6p_flags & INP_CONTROLOPTS) != 0 ||
626 	    SOFLOW_ENABLED(in6p->in6p_socket) ||
627 	    SO_RECV_CONTROL_OPTS(in6p->in6p_socket)) {
628 		ret = ip6_savecontrol(in6p, m, &opts);
629 		if (ret != 0) {
630 			udp_unlock(in6p->in6p_socket, 1, 0);
631 			goto bad;
632 		}
633 	}
634 	m_adj(m, off + sizeof(struct udphdr));
635 	if (nstat_collect) {
636 		INP_ADD_STAT(in6p, cell, wifi, wired, rxpackets, 1);
637 		INP_ADD_STAT(in6p, cell, wifi, wired, rxbytes, m->m_pkthdr.len);
638 		inp_set_activity_bitmap(in6p);
639 	}
640 	so_recv_data_stat(in6p->in6p_socket, m, 0);
641 	if (sbappendaddr(&in6p->in6p_socket->so_rcv,
642 	    (struct sockaddr *)&udp_in6, m, opts, NULL) == 0) {
643 		m = NULL;
644 		opts = NULL;
645 		udpstat.udps_fullsock++;
646 		udp_unlock(in6p->in6p_socket, 1, 0);
647 		goto bad;
648 	}
649 	if (is_wake_pkt) {
650 		soevent(in6p->in6p_socket, SO_FILT_HINT_LOCKED | SO_FILT_HINT_WAKE_PKT);
651 	}
652 	sorwakeup(in6p->in6p_socket);
653 	udp_unlock(in6p->in6p_socket, 1, 0);
654 	return IPPROTO_DONE;
655 bad:
656 	if (m != NULL) {
657 		m_freem(m);
658 	}
659 	if (opts != NULL) {
660 		m_freem(opts);
661 	}
662 	return IPPROTO_DONE;
663 }
664 
665 void
udp6_ctlinput(int cmd,struct sockaddr * sa,void * d,__unused struct ifnet * ifp)666 udp6_ctlinput(int cmd, struct sockaddr *sa, void *d, __unused struct ifnet *ifp)
667 {
668 	struct udphdr uh;
669 	struct ip6_hdr *ip6;
670 	struct mbuf *m;
671 	int off = 0;
672 	struct ip6ctlparam *ip6cp = NULL;
673 	struct icmp6_hdr *icmp6 = NULL;
674 	const struct sockaddr_in6 *sa6_src = NULL;
675 	void *cmdarg = NULL;
676 	void (*notify)(struct inpcb *, int) = udp_notify;
677 	struct inpcb *in6p;
678 	struct udp_portonly {
679 		u_int16_t uh_sport;
680 		u_int16_t uh_dport;
681 	} *uhp;
682 
683 	if (sa->sa_family != AF_INET6 ||
684 	    sa->sa_len != sizeof(struct sockaddr_in6)) {
685 		return;
686 	}
687 
688 	if ((unsigned)cmd >= PRC_NCMDS) {
689 		return;
690 	}
691 	if (PRC_IS_REDIRECT(cmd)) {
692 		notify = in6_rtchange;
693 		d = NULL;
694 	} else if (cmd == PRC_HOSTDEAD) {
695 		d = NULL;
696 	} else if (inet6ctlerrmap[cmd] == 0) {
697 		return;
698 	}
699 
700 	/* if the parameter is from icmp6, decode it. */
701 	if (d != NULL) {
702 		ip6cp = (struct ip6ctlparam *)d;
703 		icmp6 = ip6cp->ip6c_icmp6;
704 		m = ip6cp->ip6c_m;
705 		ip6 = ip6cp->ip6c_ip6;
706 		off = ip6cp->ip6c_off;
707 		cmdarg = ip6cp->ip6c_cmdarg;
708 		sa6_src = ip6cp->ip6c_src;
709 	} else {
710 		m = NULL;
711 		ip6 = NULL;
712 		cmdarg = NULL;
713 		sa6_src = &sa6_any;
714 	}
715 
716 	if (ip6 != NULL) {
717 #if SKYWALK
718 		union sockaddr_in_4_6 sock_laddr;
719 		struct protoctl_ev_val prctl_ev_val;
720 #endif /* SKYWALK */
721 		/*
722 		 * XXX: We assume that when IPV6 is non NULL,
723 		 * M and OFF are valid.
724 		 */
725 		/* check if we can safely examine src and dst ports */
726 		if (m->m_pkthdr.len < off + sizeof(*uhp)) {
727 			return;
728 		}
729 
730 		bzero(&uh, sizeof(uh));
731 		m_copydata(m, off, sizeof(*uhp), (caddr_t)&uh);
732 
733 		in6p = in6_pcblookup_hash(&udbinfo, &ip6->ip6_dst, uh.uh_dport, ip6_input_getdstifscope(m),
734 		    &ip6->ip6_src, uh.uh_sport, ip6_input_getsrcifscope(m), 0, NULL);
735 		if (cmd == PRC_MSGSIZE && in6p != NULL && !uuid_is_null(in6p->necp_client_uuid)) {
736 			uuid_t null_uuid;
737 			uuid_clear(null_uuid);
738 			necp_update_flow_protoctl_event(null_uuid, in6p->necp_client_uuid,
739 			    PRC_MSGSIZE, ntohl(icmp6->icmp6_mtu), 0);
740 			/*
741 			 * Avoid setting so_error when using Network.framework
742 			 * since the notification of PRC_MSGSIZE has been delivered
743 			 * through NECP.
744 			 */
745 			in6_pcbnotify(&udbinfo, sa, uh.uh_dport,
746 			    (struct sockaddr*)ip6cp->ip6c_src, uh.uh_sport,
747 			    cmd, cmdarg, NULL);
748 		} else {
749 			in6_pcbnotify(&udbinfo, sa, uh.uh_dport,
750 			    (struct sockaddr*)ip6cp->ip6c_src, uh.uh_sport,
751 			    cmd, cmdarg, notify);
752 		}
753 #if SKYWALK
754 		bzero(&prctl_ev_val, sizeof(prctl_ev_val));
755 		bzero(&sock_laddr, sizeof(sock_laddr));
756 
757 		if (cmd == PRC_MSGSIZE && icmp6 != NULL) {
758 			prctl_ev_val.val = ntohl(icmp6->icmp6_mtu);
759 		}
760 		sock_laddr.sin6.sin6_family = AF_INET6;
761 		sock_laddr.sin6.sin6_len = sizeof(sock_laddr.sin6);
762 		sock_laddr.sin6.sin6_addr = ip6->ip6_src;
763 
764 		protoctl_event_enqueue_nwk_wq_entry(ifp,
765 		    (struct sockaddr *)&sock_laddr, sa,
766 		    uh.uh_sport, uh.uh_dport, IPPROTO_UDP,
767 		    cmd, &prctl_ev_val);
768 #endif /* SKYWALK */
769 	}
770 	/*
771 	 * XXX The else condition here was broken for a long time.
772 	 * Fixing it made us deliver notification correctly but broke
773 	 * some frameworks that didn't handle it well.
774 	 * For now we have removed it and will revisit it later.
775 	 */
776 }
777 
778 static int
udp6_abort(struct socket * so)779 udp6_abort(struct socket *so)
780 {
781 	struct inpcb *inp;
782 
783 	inp = sotoinpcb(so);
784 	if (inp == NULL) {
785 		panic("%s: so=%p null inp", __func__, so);
786 		/* NOTREACHED */
787 	}
788 	soisdisconnected(so);
789 	in6_pcbdetach(inp);
790 	return 0;
791 }
792 
793 static int
udp6_attach(struct socket * so,int proto,struct proc * p)794 udp6_attach(struct socket *so, int proto, struct proc *p)
795 {
796 #pragma unused(proto)
797 	struct inpcb *inp;
798 	int error;
799 
800 	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
801 		error = soreserve(so, udp_sendspace, udp_recvspace);
802 		if (error) {
803 			return error;
804 		}
805 	}
806 
807 	inp = sotoinpcb(so);
808 	if (inp != NULL) {
809 		return EINVAL;
810 	}
811 
812 	error = in_pcballoc(so, &udbinfo, p);
813 	if (error) {
814 		return error;
815 	}
816 
817 	inp = (struct inpcb *)so->so_pcb;
818 	inp->inp_vflag |= INP_IPV6;
819 	if (ip6_mapped_addr_on) {
820 		inp->inp_vflag |= INP_IPV4;
821 	}
822 	inp->in6p_hops = -1;    /* use kernel default */
823 	inp->in6p_cksum = -1;   /* just to be sure */
824 	/*
825 	 * XXX: ugly!!
826 	 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
827 	 * because the socket may be bound to an IPv6 wildcard address,
828 	 * which may match an IPv4-mapped IPv6 address.
829 	 */
830 	inp->inp_ip_ttl = (u_char)ip_defttl;
831 	if (nstat_collect) {
832 		nstat_udp_new_pcb(inp);
833 	}
834 	return 0;
835 }
836 
837 static int
udp6_bind(struct socket * so,struct sockaddr * nam,struct proc * p)838 udp6_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
839 {
840 	struct inpcb *inp;
841 	int error;
842 
843 	inp = sotoinpcb(so);
844 	if (inp == NULL) {
845 		return EINVAL;
846 	}
847 	/*
848 	 * Another thread won the binding race so do not change inp_vflag
849 	 */
850 	if (inp->inp_flags2 & INP2_BIND_IN_PROGRESS) {
851 		return EINVAL;
852 	}
853 
854 	const uint8_t old_flags = inp->inp_vflag;
855 	inp->inp_vflag &= ~INP_IPV4;
856 	inp->inp_vflag |= INP_IPV6;
857 
858 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
859 		struct sockaddr_in6 *sin6_p;
860 
861 		sin6_p = (struct sockaddr_in6 *)(void *)nam;
862 
863 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr)) {
864 			inp->inp_vflag |= INP_IPV4;
865 			inp->inp_vflag &= ~INP_V4MAPPEDV6;
866 		} else if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
867 			struct sockaddr_in sin;
868 
869 			in6_sin6_2_sin(&sin, sin6_p);
870 			inp->inp_vflag |= INP_IPV4;
871 			inp->inp_vflag &= ~INP_IPV6;
872 			inp->inp_vflag |= INP_V4MAPPEDV6;
873 
874 			error = in_pcbbind(inp, (struct sockaddr *)&sin, p);
875 			if (error != 0) {
876 				inp->inp_vflag = old_flags;
877 			}
878 			return error;
879 		}
880 	}
881 
882 	error = in6_pcbbind(inp, nam, p);
883 	if (error != 0) {
884 		inp->inp_vflag = old_flags;
885 	}
886 
887 	UDP_LOG_BIND(inp, error);
888 
889 	return error;
890 }
891 
892 int
udp6_connect(struct socket * so,struct sockaddr * nam,struct proc * p)893 udp6_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
894 {
895 	struct inpcb *inp;
896 	int error;
897 	struct sockaddr_in6 *sin6_p = (struct sockaddr_in6 *)(void *)nam;
898 
899 #if defined(NECP) && defined(FLOW_DIVERT)
900 	int should_use_flow_divert = 0;
901 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
902 
903 	inp = sotoinpcb(so);
904 	if (inp == NULL) {
905 		return EINVAL;
906 	}
907 
908 #if defined(NECP) && defined(FLOW_DIVERT)
909 	should_use_flow_divert = necp_socket_should_use_flow_divert(inp);
910 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
911 
912 	/*
913 	 * It is possible that the socket is bound to v4 mapped v6 address.
914 	 * Post that do not allow connect to a v6 endpoint.
915 	 */
916 	if (inp->inp_vflag & INP_V4MAPPEDV6 &&
917 	    !IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
918 		if (IN6_IS_ADDR_UNSPECIFIED(&sin6_p->sin6_addr)) {
919 			sin6_p->sin6_addr.s6_addr[10] = 0xff;
920 			sin6_p->sin6_addr.s6_addr[11] = 0xff;
921 		} else {
922 			return EINVAL;
923 		}
924 	}
925 
926 	if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
927 		if (IN6_IS_ADDR_V4MAPPED(&sin6_p->sin6_addr)) {
928 			struct sockaddr_in sin;
929 			const uint8_t old_flags = inp->inp_vflag;
930 
931 			if (inp->inp_faddr.s_addr != INADDR_ANY) {
932 				return EISCONN;
933 			}
934 
935 			if (!(so->so_flags1 & SOF1_CONNECT_COUNTED)) {
936 				so->so_flags1 |= SOF1_CONNECT_COUNTED;
937 				INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet_dgram_connected);
938 			}
939 
940 			in6_sin6_2_sin(&sin, sin6_p);
941 #if defined(NECP) && defined(FLOW_DIVERT)
942 			if (should_use_flow_divert) {
943 				goto do_flow_divert;
944 			}
945 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
946 			inp->inp_vflag |= INP_IPV4;
947 			inp->inp_vflag &= ~INP_IPV6;
948 			inp->inp_vflag |= INP_V4MAPPEDV6;
949 
950 			error = in_pcbconnect(inp, (struct sockaddr *)&sin,
951 			    p, IFSCOPE_NONE, NULL);
952 			if (error == 0) {
953 #if NECP
954 				/* Update NECP client with connected five-tuple */
955 				if (!uuid_is_null(inp->necp_client_uuid)) {
956 					socket_unlock(so, 0);
957 					necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
958 					socket_lock(so, 0);
959 				}
960 #endif /* NECP */
961 				soisconnected(so);
962 			} else {
963 				inp->inp_vflag = old_flags;
964 			}
965 			UDP_LOG_CONNECT(inp, error);
966 			return error;
967 		}
968 	}
969 
970 	if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
971 		return EISCONN;
972 	}
973 
974 	if (!(so->so_flags1 & SOF1_CONNECT_COUNTED)) {
975 		so->so_flags1 |= SOF1_CONNECT_COUNTED;
976 		INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet6_dgram_connected);
977 	}
978 
979 #if defined(NECP) && defined(FLOW_DIVERT)
980 do_flow_divert:
981 	if (should_use_flow_divert) {
982 		error = flow_divert_pcb_init(so);
983 		if (error == 0) {
984 			error = flow_divert_connect_out(so, nam, p);
985 		}
986 		return error;
987 	}
988 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
989 
990 	error = in6_pcbconnect(inp, nam, p);
991 	if (error == 0) {
992 		/* should be non mapped addr */
993 		if (ip6_mapped_addr_on ||
994 		    (inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
995 			inp->inp_vflag &= ~INP_IPV4;
996 			inp->inp_vflag |= INP_IPV6;
997 		}
998 #if NECP
999 		/* Update NECP client with connected five-tuple */
1000 		if (!uuid_is_null(inp->necp_client_uuid)) {
1001 			socket_unlock(so, 0);
1002 			necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
1003 			socket_lock(so, 0);
1004 		}
1005 #endif /* NECP */
1006 		soisconnected(so);
1007 		if (inp->inp_flowhash == 0) {
1008 			inp_calc_flowhash(inp);
1009 			ASSERT(inp->inp_flowhash != 0);
1010 		}
1011 		/* update flowinfo - RFC 6437 */
1012 		if (inp->inp_flow == 0 &&
1013 		    inp->in6p_flags & IN6P_AUTOFLOWLABEL) {
1014 			inp->inp_flow &= ~IPV6_FLOWLABEL_MASK;
1015 			inp->inp_flow |=
1016 			    (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
1017 		}
1018 		inp->inp_connect_timestamp = mach_continuous_time();
1019 	}
1020 	UDP_LOG_CONNECT(inp, error);
1021 	return error;
1022 }
1023 
1024 static int
udp6_connectx(struct socket * so,struct sockaddr * src,struct sockaddr * dst,struct proc * p,uint32_t ifscope,sae_associd_t aid,sae_connid_t * pcid,uint32_t flags,void * arg,uint32_t arglen,struct uio * uio,user_ssize_t * bytes_written)1025 udp6_connectx(struct socket *so, struct sockaddr *src,
1026     struct sockaddr *dst, struct proc *p, uint32_t ifscope,
1027     sae_associd_t aid, sae_connid_t *pcid, uint32_t flags, void *arg,
1028     uint32_t arglen, struct uio *uio, user_ssize_t *bytes_written)
1029 {
1030 	return udp_connectx_common(so, AF_INET6, src, dst,
1031 	           p, ifscope, aid, pcid, flags, arg, arglen, uio, bytes_written);
1032 }
1033 
1034 static int
udp6_detach(struct socket * so)1035 udp6_detach(struct socket *so)
1036 {
1037 	struct inpcb *inp;
1038 
1039 	inp = sotoinpcb(so);
1040 	if (inp == NULL) {
1041 		return EINVAL;
1042 	}
1043 
1044 	UDP_LOG_CONNECTION_SUMMARY(inp);
1045 
1046 	in6_pcbdetach(inp);
1047 	return 0;
1048 }
1049 
1050 static int
udp6_disconnect(struct socket * so)1051 udp6_disconnect(struct socket *so)
1052 {
1053 	struct inpcb *inp;
1054 
1055 	inp = sotoinpcb(so);
1056 	if (inp == NULL
1057 #if NECP
1058 	    || (necp_socket_should_use_flow_divert(inp))
1059 #endif /* NECP */
1060 	    ) {
1061 		return inp == NULL ? EINVAL : EPROTOTYPE;
1062 	}
1063 
1064 	if (inp->inp_vflag & INP_IPV4) {
1065 		struct pr_usrreqs *pru;
1066 
1067 		pru = ip_protox[IPPROTO_UDP]->pr_usrreqs;
1068 		return (*pru->pru_disconnect)(so);
1069 	}
1070 
1071 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1072 		return ENOTCONN;
1073 	}
1074 
1075 	UDP_LOG_CONNECTION_SUMMARY(inp);
1076 
1077 	in6_pcbdisconnect(inp);
1078 
1079 	/* reset flow-controlled state, just in case */
1080 	inp_reset_fc_state(inp);
1081 
1082 	inp->in6p_laddr = in6addr_any;
1083 	inp->inp_lifscope = IFSCOPE_NONE;
1084 	inp->in6p_last_outifp = NULL;
1085 #if SKYWALK
1086 	if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
1087 		netns_set_ifnet(&inp->inp_netns_token, NULL);
1088 	}
1089 #endif /* SKYWALK */
1090 
1091 	so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1092 	return 0;
1093 }
1094 
1095 static int
udp6_disconnectx(struct socket * so,sae_associd_t aid,sae_connid_t cid)1096 udp6_disconnectx(struct socket *so, sae_associd_t aid, sae_connid_t cid)
1097 {
1098 #pragma unused(cid)
1099 	if (aid != SAE_ASSOCID_ANY && aid != SAE_ASSOCID_ALL) {
1100 		return EINVAL;
1101 	}
1102 
1103 	return udp6_disconnect(so);
1104 }
1105 
1106 static int
udp6_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct proc * p)1107 udp6_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1108     struct mbuf *control, struct proc *p)
1109 {
1110 	struct inpcb *inp;
1111 	int error = 0;
1112 #if defined(NECP) && defined(FLOW_DIVERT)
1113 	int should_use_flow_divert = 0;
1114 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
1115 #if CONTENT_FILTER
1116 	struct m_tag *cfil_tag = NULL;
1117 	struct sockaddr *cfil_faddr = NULL;
1118 #endif
1119 
1120 	inp = sotoinpcb(so);
1121 	if (inp == NULL) {
1122 		error = EINVAL;
1123 		goto bad;
1124 	}
1125 
1126 #if CONTENT_FILTER
1127 	//If socket is subject to UDP Content Filter and unconnected, get addr from tag.
1128 	if (CFIL_DGRAM_FILTERED(so) && !addr && IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
1129 		cfil_tag = cfil_dgram_get_socket_state(m, NULL, NULL, &cfil_faddr, NULL);
1130 		if (cfil_tag) {
1131 			addr = (struct sockaddr *)cfil_faddr;
1132 		}
1133 	}
1134 #endif
1135 
1136 #if defined(NECP) && defined(FLOW_DIVERT)
1137 	should_use_flow_divert = necp_socket_should_use_flow_divert(inp);
1138 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
1139 
1140 	if (addr != NULL) {
1141 		if (addr->sa_len != sizeof(struct sockaddr_in6)) {
1142 			error = EINVAL;
1143 			goto bad;
1144 		}
1145 		if (addr->sa_family != AF_INET6) {
1146 			error = EAFNOSUPPORT;
1147 			goto bad;
1148 		}
1149 	}
1150 
1151 	if (ip6_mapped_addr_on || (inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
1152 		int hasv4addr;
1153 		struct sockaddr_in6 *sin6 = NULL;
1154 
1155 		if (addr == NULL) {
1156 			hasv4addr = (inp->inp_vflag & INP_IPV4);
1157 		} else {
1158 			sin6 = (struct sockaddr_in6 *)(void *)addr;
1159 			hasv4addr =
1160 			    IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr) ? 1 : 0;
1161 		}
1162 		if (hasv4addr) {
1163 			struct pr_usrreqs *pru;
1164 
1165 			if (sin6 != NULL) {
1166 				in6_sin6_2_sin_in_sock(addr);
1167 			}
1168 #if defined(NECP) && defined(FLOW_DIVERT)
1169 			if (should_use_flow_divert) {
1170 				goto do_flow_divert;
1171 			}
1172 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
1173 			pru = ip_protox[IPPROTO_UDP]->pr_usrreqs;
1174 			error = ((*pru->pru_send)(so, flags, m, addr,
1175 			    control, p));
1176 #if CONTENT_FILTER
1177 			if (cfil_tag) {
1178 				m_tag_free(cfil_tag);
1179 			}
1180 #endif
1181 			/* addr will just be freed in sendit(). */
1182 			return error;
1183 		}
1184 	}
1185 
1186 #if defined(NECP) && defined(FLOW_DIVERT)
1187 do_flow_divert:
1188 	if (should_use_flow_divert) {
1189 		/* Implicit connect */
1190 		error = flow_divert_implicit_data_out(so, flags, m, addr, control, p);
1191 #if CONTENT_FILTER
1192 		if (cfil_tag) {
1193 			m_tag_free(cfil_tag);
1194 		}
1195 #endif
1196 		return error;
1197 	}
1198 #endif /* defined(NECP) && defined(FLOW_DIVERT) */
1199 
1200 #if SKYWALK
1201 	sk_protect_t protect = sk_async_transmit_protect();
1202 #endif /* SKYWALK */
1203 	error = udp6_output(inp, m, addr, control, p);
1204 #if SKYWALK
1205 	sk_async_transmit_unprotect(protect);
1206 #endif /* SKYWALK */
1207 
1208 #if CONTENT_FILTER
1209 	if (cfil_tag) {
1210 		m_tag_free(cfil_tag);
1211 	}
1212 #endif
1213 	return error;
1214 
1215 bad:
1216 	VERIFY(error != 0);
1217 
1218 	if (m != NULL) {
1219 		m_freem(m);
1220 	}
1221 	if (control != NULL) {
1222 		m_freem(control);
1223 	}
1224 #if CONTENT_FILTER
1225 	if (cfil_tag) {
1226 		m_tag_free(cfil_tag);
1227 	}
1228 #endif
1229 	return error;
1230 }
1231 
1232 /*
1233  * Checksum extended UDP header and data.
1234  */
1235 static int
udp6_input_checksum(struct mbuf * m,struct udphdr * uh,int off,int ulen)1236 udp6_input_checksum(struct mbuf *m, struct udphdr *uh, int off, int ulen)
1237 {
1238 	struct ifnet *ifp = m->m_pkthdr.rcvif;
1239 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1240 
1241 	if (!(m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
1242 	    uh->uh_sum == 0) {
1243 		/* UDP/IPv6 checksum is mandatory (RFC2460) */
1244 
1245 		/*
1246 		 * If checksum was already validated, ignore this check.
1247 		 * This is necessary for transport-mode ESP, which may be
1248 		 * getting UDP payloads without checksums when the network
1249 		 * has a NAT64.
1250 		 */
1251 		udpstat.udps_nosum++;
1252 		goto badsum;
1253 	}
1254 
1255 	if ((hwcksum_rx || (ifp->if_flags & IFF_LOOPBACK) ||
1256 	    (m->m_pkthdr.pkt_flags & PKTF_LOOP)) &&
1257 	    (m->m_pkthdr.csum_flags & CSUM_DATA_VALID)) {
1258 		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
1259 			uh->uh_sum = m->m_pkthdr.csum_rx_val;
1260 		} else {
1261 			uint32_t sum = m->m_pkthdr.csum_rx_val;
1262 			uint32_t start = m->m_pkthdr.csum_rx_start;
1263 			int32_t trailer = (m_pktlen(m) - (off + ulen));
1264 
1265 			/*
1266 			 * Perform 1's complement adjustment of octets
1267 			 * that got included/excluded in the hardware-
1268 			 * calculated checksum value.  Also take care
1269 			 * of any trailing bytes and subtract out
1270 			 * their partial sum.
1271 			 */
1272 			ASSERT(trailer >= 0);
1273 			if ((m->m_pkthdr.csum_flags & CSUM_PARTIAL) &&
1274 			    (start != off || trailer != 0)) {
1275 				uint32_t swbytes = (uint32_t)trailer;
1276 				uint16_t s = 0, d = 0;
1277 
1278 				if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) {
1279 					s = ip6->ip6_src.s6_addr16[1];
1280 					ip6->ip6_src.s6_addr16[1] = 0;
1281 				}
1282 				if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
1283 					d = ip6->ip6_dst.s6_addr16[1];
1284 					ip6->ip6_dst.s6_addr16[1] = 0;
1285 				}
1286 
1287 				/* callee folds in sum */
1288 				sum = m_adj_sum16(m, start, off, ulen, sum);
1289 				if (off > start) {
1290 					swbytes += (off - start);
1291 				} else {
1292 					swbytes += (start - off);
1293 				}
1294 
1295 				if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) {
1296 					ip6->ip6_src.s6_addr16[1] = s;
1297 				}
1298 				if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
1299 					ip6->ip6_dst.s6_addr16[1] = d;
1300 				}
1301 
1302 				if (swbytes != 0) {
1303 					udp_in_cksum_stats(swbytes);
1304 				}
1305 				if (trailer != 0) {
1306 					m_adj(m, -trailer);
1307 				}
1308 			}
1309 
1310 			uh->uh_sum = in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst,
1311 			    sum + htonl(ulen + IPPROTO_UDP));
1312 		}
1313 		uh->uh_sum ^= 0xffff;
1314 	} else {
1315 		udp_in6_cksum_stats(ulen);
1316 		uh->uh_sum = in6_cksum(m, IPPROTO_UDP, off, ulen);
1317 	}
1318 
1319 	if (uh->uh_sum != 0) {
1320 badsum:
1321 		udpstat.udps_badsum++;
1322 		IF_UDP_STATINC(ifp, badchksum);
1323 		return -1;
1324 	}
1325 
1326 	return 0;
1327 }
1328 
1329 int
udp6_defunct(struct socket * so)1330 udp6_defunct(struct socket *so)
1331 {
1332 	struct ip_moptions *imo;
1333 	struct ip6_moptions *im6o;
1334 	struct inpcb *inp;
1335 
1336 	inp = sotoinpcb(so);
1337 	if (inp == NULL) {
1338 		return EINVAL;
1339 	}
1340 
1341 	im6o = inp->in6p_moptions;
1342 	inp->in6p_moptions = NULL;
1343 	if (im6o != NULL) {
1344 		struct proc *p = current_proc();
1345 
1346 		SODEFUNCTLOG("%s[%d, %s]: defuncting so 0x%llu drop ipv6 multicast memberships",
1347 		    __func__, proc_pid(p), proc_best_name(p),
1348 		    so->so_gencnt);
1349 		IM6O_REMREF(im6o);
1350 	}
1351 	imo = inp->inp_moptions;
1352 	if (imo != NULL) {
1353 		struct proc *p = current_proc();
1354 
1355 		SODEFUNCTLOG("%s[%d, %s]: defuncting so 0x%llu drop ipv4 multicast memberships",
1356 		    __func__, proc_pid(p), proc_best_name(p),
1357 		    so->so_gencnt);
1358 
1359 		inp->inp_moptions = NULL;
1360 
1361 		IMO_REMREF(imo);
1362 	}
1363 
1364 	return 0;
1365 }
1366