xref: /xnu-8792.81.2/bsd/netinet6/udp6_output.c (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)
1 /*
2  * Copyright (c) 2000-2021 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 
30 /*	$FreeBSD: src/sys/netinet6/udp6_output.c,v 1.1.2.3 2001/08/31 13:49:58 jlemon Exp $	*/
31 /*	$KAME: udp6_output.c,v 1.31 2001/05/21 16:39:15 jinmei Exp $	*/
32 
33 /*
34  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
35  * 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 project 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 PROJECT 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 PROJECT 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 
62 /*
63  * Copyright (c) 1982, 1986, 1989, 1993
64  *	The Regents of the University of California.  All rights reserved.
65  *
66  * Redistribution and use in source and binary forms, with or without
67  * modification, are permitted provided that the following conditions
68  * are met:
69  * 1. Redistributions of source code must retain the above copyright
70  *    notice, this list of conditions and the following disclaimer.
71  * 2. Redistributions in binary form must reproduce the above copyright
72  *    notice, this list of conditions and the following disclaimer in the
73  *    documentation and/or other materials provided with the distribution.
74  * 3. All advertising materials mentioning features or use of this software
75  *    must display the following acknowledgement:
76  *	This product includes software developed by the University of
77  *	California, Berkeley and its contributors.
78  * 4. Neither the name of the University nor the names of its contributors
79  *    may be used to endorse or promote products derived from this software
80  *    without specific prior written permission.
81  *
82  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
83  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
84  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
85  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
86  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
87  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
88  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
89  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
90  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
91  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
92  * SUCH DAMAGE.
93  *
94  *	@(#)udp_var.h	8.1 (Berkeley) 6/10/93
95  */
96 
97 #include <sys/param.h>
98 #include <sys/malloc.h>
99 #include <sys/mbuf.h>
100 #include <sys/protosw.h>
101 #include <sys/socket.h>
102 #include <sys/socketvar.h>
103 #include <sys/sysctl.h>
104 #include <sys/errno.h>
105 #include <sys/stat.h>
106 #include <sys/systm.h>
107 #include <sys/proc.h>
108 #include <sys/syslog.h>
109 
110 #include <machine/endian.h>
111 
112 #include <net/if.h>
113 #include <net/route.h>
114 #include <net/if_types.h>
115 #include <net/ntstat.h>
116 
117 #include <netinet/in.h>
118 #include <netinet/in_var.h>
119 #include <netinet/in_systm.h>
120 #include <netinet/in_tclass.h>
121 #include <netinet/ip.h>
122 #include <netinet/ip_var.h>
123 #include <netinet/in_pcb.h>
124 #include <netinet/udp.h>
125 #include <netinet/udp_var.h>
126 #include <netinet/ip6.h>
127 #include <netinet6/ip6_var.h>
128 #include <netinet6/in6_pcb.h>
129 #include <netinet6/udp6_var.h>
130 #include <netinet/icmp6.h>
131 #include <netinet6/ip6protosw.h>
132 
133 #if NECP
134 #include <net/necp.h>
135 #endif /* NECP */
136 
137 #include <net/net_osdep.h>
138 
139 #if CONTENT_FILTER
140 #include <net/content_filter.h>
141 #endif /* CONTENT_FILTER */
142 
143 /*
144  * UDP protocol inplementation.
145  * Per RFC 768, August, 1980.
146  */
147 extern int soreserveheadroom;
148 
149 int
udp6_output(struct in6pcb * in6p,struct mbuf * m,struct sockaddr * addr6,struct mbuf * control,struct proc * p)150 udp6_output(struct in6pcb *in6p, struct mbuf *m, struct sockaddr *addr6,
151     struct mbuf *control, struct proc *p)
152 {
153 	u_int32_t ulen = m->m_pkthdr.len;
154 	u_int32_t plen = sizeof(struct udphdr) + ulen;
155 	struct ip6_hdr *ip6;
156 	struct udphdr *udp6;
157 	struct in6_addr *laddr, *faddr;
158 	u_short fport;
159 	int error = 0;
160 	struct ip6_pktopts opt, *optp = NULL;
161 	struct ip6_moptions *im6o;
162 	int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
163 	int flags;
164 	struct sockaddr_in6 tmp;
165 	struct  in6_addr storage;
166 	int sotc = SO_TC_UNSPEC;
167 	int netsvctype = _NET_SERVICE_TYPE_UNSPEC;
168 	struct ip6_out_args ip6oa;
169 	struct flowadv *adv = &ip6oa.ip6oa_flowadv;
170 	struct socket *so = in6p->in6p_socket;
171 	struct route_in6 ro;
172 	int flowadv = 0;
173 	bool sndinprog_cnt_used = false;
174 #if CONTENT_FILTER
175 	struct m_tag *cfil_tag = NULL;
176 	bool cfil_faddr_use = false;
177 	uint32_t cfil_so_state_change_cnt = 0;
178 	struct sockaddr *cfil_faddr = NULL;
179 	struct sockaddr_in6 *cfil_sin6 = NULL;
180 #endif
181 	bool check_qos_marking_again = (so->so_flags1 & SOF1_QOSMARKING_POLICY_OVERRIDE) ? FALSE : TRUE;
182 	uint32_t lifscope = IFSCOPE_NONE, fifscope = IFSCOPE_NONE;
183 
184 	bzero(&ip6oa, sizeof(ip6oa));
185 	ip6oa.ip6oa_boundif = IFSCOPE_NONE;
186 	ip6oa.ip6oa_flags = IP6OAF_SELECT_SRCIF;
187 
188 	/* Enable flow advisory only when connected */
189 	flowadv = (so->so_state & SS_ISCONNECTED) ? 1 : 0;
190 
191 	if (flowadv && INP_WAIT_FOR_IF_FEEDBACK(in6p)) {
192 		error = ENOBUFS;
193 		goto release;
194 	}
195 
196 	if (in6p->inp_flags & INP_BOUND_IF) {
197 		ip6oa.ip6oa_boundif = in6p->inp_boundifp->if_index;
198 		ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF;
199 	} else if (!in6_embedded_scope && IN6_IS_SCOPE_EMBED(&in6p->in6p_faddr)) {
200 		ip6oa.ip6oa_boundif = in6p->inp_fifscope;
201 		ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF;
202 	}
203 	if (INP_NO_CELLULAR(in6p)) {
204 		ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR;
205 	}
206 	if (INP_NO_EXPENSIVE(in6p)) {
207 		ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE;
208 	}
209 	if (INP_NO_CONSTRAINED(in6p)) {
210 		ip6oa.ip6oa_flags |= IP6OAF_NO_CONSTRAINED;
211 	}
212 	if (INP_AWDL_UNRESTRICTED(in6p)) {
213 		ip6oa.ip6oa_flags |= IP6OAF_AWDL_UNRESTRICTED;
214 	}
215 	if (INP_INTCOPROC_ALLOWED(in6p)) {
216 		ip6oa.ip6oa_flags |= IP6OAF_INTCOPROC_ALLOWED;
217 	}
218 
219 #if CONTENT_FILTER
220 	/*
221 	 * If socket is subject to UDP Content Filter and no addr is passed in,
222 	 * retrieve CFIL saved state from mbuf and use it if necessary.
223 	 */
224 	if (CFIL_DGRAM_FILTERED(so) && !addr6) {
225 		cfil_tag = cfil_dgram_get_socket_state(m, &cfil_so_state_change_cnt, NULL, &cfil_faddr, NULL);
226 		if (cfil_tag) {
227 			cfil_sin6 = (struct sockaddr_in6 *)(void *)cfil_faddr;
228 			if ((so->so_state_change_cnt != cfil_so_state_change_cnt) &&
229 			    (in6p->in6p_fport != cfil_sin6->sin6_port ||
230 			    !in6_are_addr_equal_scoped(&in6p->in6p_faddr, &cfil_sin6->sin6_addr, in6p->inp_fifscope, cfil_sin6->sin6_scope_id))) {
231 				/*
232 				 * Socket is connected but socket state and dest addr/port changed.
233 				 * We need to use the saved faddr info.
234 				 */
235 				cfil_faddr_use = true;
236 			}
237 		}
238 	}
239 #endif
240 
241 	if (control) {
242 		sotc = so_tc_from_control(control, &netsvctype);
243 		if ((error = ip6_setpktopts(control, &opt,
244 		    NULL, IPPROTO_UDP)) != 0) {
245 			goto release;
246 		}
247 		optp = &opt;
248 	} else {
249 		optp = in6p->in6p_outputopts;
250 	}
251 
252 	if (sotc == SO_TC_UNSPEC) {
253 		sotc = so->so_traffic_class;
254 		netsvctype = so->so_netsvctype;
255 	}
256 	ip6oa.ip6oa_sotc = sotc;
257 	ip6oa.ip6oa_netsvctype = netsvctype;
258 
259 	in6p->inp_sndinprog_cnt++;
260 	sndinprog_cnt_used = true;
261 
262 	if (addr6) {
263 		/*
264 		 * IPv4 version of udp_output calls in_pcbconnect in this case,
265 		 * which has its costs.
266 		 *
267 		 * Since we saw no essential reason for calling in_pcbconnect,
268 		 * we get rid of such kind of logic, and call in6_selectsrc
269 		 * and in6_pcbsetport in order to fill in the local address
270 		 * and the local port.
271 		 */
272 		struct sockaddr_in6 *sin6 =
273 		    (struct sockaddr_in6 *)(void *)addr6;
274 
275 		if (sin6->sin6_port == 0) {
276 			error = EADDRNOTAVAIL;
277 			goto release;
278 		}
279 
280 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
281 			/* how about ::ffff:0.0.0.0 case? */
282 			error = EISCONN;
283 			goto release;
284 		}
285 
286 		/* protect *sin6 from overwrites */
287 		tmp = *sin6;
288 		sin6 = &tmp;
289 
290 		faddr = &sin6->sin6_addr;
291 		fport = sin6->sin6_port; /* allow 0 port */
292 
293 		if (IN6_IS_ADDR_V4MAPPED(faddr)) {
294 			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
295 				/*
296 				 * I believe we should explicitly discard the
297 				 * packet when mapped addresses are disabled,
298 				 * rather than send the packet as an IPv6 one.
299 				 * If we chose the latter approach, the packet
300 				 * might be sent out on the wire based on the
301 				 * default route, the situation which we'd
302 				 * probably want to avoid.
303 				 * (20010421 [email protected])
304 				 */
305 				error = EINVAL;
306 				goto release;
307 			} else {
308 				af = AF_INET;
309 			}
310 		}
311 
312 		/* KAME hack: embed scopeid */
313 		if (in6_embedscope(&sin6->sin6_addr, sin6, in6p, NULL,
314 		    optp, IN6_NULL_IF_EMBEDDED_SCOPE(&sin6->sin6_scope_id)) != 0) {
315 			error = EINVAL;
316 			goto release;
317 		}
318 		fifscope = sin6->sin6_scope_id;
319 
320 		if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
321 			struct ifnet *src_ifp = NULL;
322 			laddr = in6_selectsrc(sin6, optp,
323 			    in6p, &in6p->in6p_route, &src_ifp, &storage,
324 			    ip6oa.ip6oa_boundif, &error);
325 			if (src_ifp != NULL) {
326 				lifscope = src_ifp->if_index;
327 				ifnet_release(src_ifp);
328 			}
329 		} else {
330 			laddr = &in6p->in6p_laddr;      /* XXX */
331 			lifscope = in6p->inp_lifscope;
332 		}
333 		if (laddr == NULL) {
334 			if (error == 0) {
335 				error = EADDRNOTAVAIL;
336 			}
337 			goto release;
338 		}
339 		if (in6p->in6p_lport == 0 &&
340 		    (error = in6_pcbsetport(laddr, in6p, p, 0)) != 0) {
341 			goto release;
342 		}
343 	} else {
344 		if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
345 			error = ENOTCONN;
346 			goto release;
347 		}
348 		laddr = &in6p->in6p_laddr;
349 		faddr = &in6p->in6p_faddr;
350 		fport = in6p->in6p_fport;
351 		fifscope = in6p->inp_fifscope;
352 		lifscope = in6p->inp_lifscope;
353 #if CONTENT_FILTER
354 		if (cfil_faddr_use) {
355 			faddr = &((struct sockaddr_in6 *)(void *)cfil_faddr)->sin6_addr;
356 			fport = ((struct sockaddr_in6 *)(void *)cfil_faddr)->sin6_port;
357 			fifscope = ((struct sockaddr_in6 *)(void *)cfil_faddr)->sin6_scope_id;
358 
359 			/* Do not use cached route */
360 			ROUTE_RELEASE(&in6p->in6p_route);
361 		}
362 #endif
363 		if (IN6_IS_ADDR_V4MAPPED(faddr)) {
364 			if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY)) {
365 				/*
366 				 * XXX: this case would happen when the
367 				 * application sets the V6ONLY flag after
368 				 * connecting the foreign address.
369 				 * Such applications should be fixed,
370 				 * so we bark here.
371 				 */
372 				log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
373 				    "option was set for a connected socket\n");
374 				error = EINVAL;
375 				goto release;
376 			} else {
377 				af = AF_INET;
378 			}
379 		}
380 	}
381 
382 	if (in6p->inp_flowhash == 0) {
383 		inp_calc_flowhash(in6p);
384 		ASSERT(in6p->inp_flowhash != 0);
385 	}
386 	/* update flowinfo - RFC 6437 */
387 	if (in6p->inp_flow == 0 && in6p->in6p_flags & IN6P_AUTOFLOWLABEL) {
388 		in6p->inp_flow &= ~IPV6_FLOWLABEL_MASK;
389 		in6p->inp_flow |=
390 		    (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
391 	}
392 
393 	if (af == AF_INET) {
394 		hlen = sizeof(struct ip);
395 	}
396 
397 	if (fport == htons(53) && !(so->so_flags1 & SOF1_DNS_COUNTED)) {
398 		so->so_flags1 |= SOF1_DNS_COUNTED;
399 		INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet_dgram_dns);
400 	}
401 
402 	/*
403 	 * Calculate data length and get a mbuf
404 	 * for UDP and IP6 headers.
405 	 */
406 	M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT, 1);
407 	if (m == 0) {
408 		error = ENOBUFS;
409 		goto release;
410 	}
411 
412 	/*
413 	 * Stuff checksum and output datagram.
414 	 */
415 	udp6 = (struct udphdr *)(void *)(mtod(m, caddr_t) + hlen);
416 	udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
417 	udp6->uh_dport = fport;
418 	if (plen <= 0xffff) {
419 		udp6->uh_ulen = htons((u_short)plen);
420 	} else {
421 		udp6->uh_ulen = 0;
422 	}
423 	udp6->uh_sum = 0;
424 
425 	switch (af) {
426 	case AF_INET6:
427 		ip6 = mtod(m, struct ip6_hdr *);
428 		ip6->ip6_flow   = in6p->inp_flow & IPV6_FLOWINFO_MASK;
429 		ip6->ip6_vfc    &= ~IPV6_VERSION_MASK;
430 		ip6->ip6_vfc    |= IPV6_VERSION;
431 #if 0           /* ip6_plen will be filled in ip6_output. */
432 		ip6->ip6_plen   = htons((u_short)plen);
433 #endif
434 		ip6->ip6_nxt    = IPPROTO_UDP;
435 		ip6->ip6_hlim   = in6_selecthlim(in6p, in6p->in6p_route.ro_rt ?
436 		    in6p->in6p_route.ro_rt->rt_ifp : NULL);
437 		ip6->ip6_src    = *laddr;
438 		ip6->ip6_dst    = *faddr;
439 
440 		udp6->uh_sum = in6_pseudo(laddr, faddr,
441 		    htonl(plen + IPPROTO_UDP));
442 		m->m_pkthdr.csum_flags = (CSUM_UDPIPV6 | CSUM_ZERO_INVERT);
443 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
444 
445 		if (!IN6_IS_ADDR_UNSPECIFIED(laddr)) {
446 			ip6oa.ip6oa_flags |= IP6OAF_BOUND_SRCADDR;
447 		}
448 
449 		flags = IPV6_OUTARGS;
450 
451 		udp6stat.udp6s_opackets++;
452 
453 #if NECP
454 		{
455 			necp_kernel_policy_id policy_id;
456 			necp_kernel_policy_id skip_policy_id;
457 			u_int32_t route_rule_id;
458 			u_int32_t pass_flags;
459 
460 			/*
461 			 * We need a route to perform NECP route rule checks
462 			 */
463 			if (net_qos_policy_restricted != 0 &&
464 			    ROUTE_UNUSABLE(&in6p->inp_route)) {
465 				struct sockaddr_in6 to;
466 				struct sockaddr_in6 from;
467 
468 				ROUTE_RELEASE(&in6p->inp_route);
469 
470 				bzero(&from, sizeof(struct sockaddr_in6));
471 				from.sin6_family = AF_INET6;
472 				from.sin6_len = sizeof(struct sockaddr_in6);
473 				from.sin6_addr = *laddr;
474 
475 				bzero(&to, sizeof(struct sockaddr_in6));
476 				to.sin6_family = AF_INET6;
477 				to.sin6_len = sizeof(struct sockaddr_in6);
478 				to.sin6_addr = *faddr;
479 
480 				in6p->inp_route.ro_dst.sa_family = AF_INET6;
481 				in6p->inp_route.ro_dst.sa_len = sizeof(struct sockaddr_in6);
482 				((struct sockaddr_in6 *)(void *)&in6p->inp_route.ro_dst)->sin6_addr =
483 				    *faddr;
484 
485 				if (!in6_embedded_scope) {
486 					((struct sockaddr_in6 *)(void *)&in6p->inp_route.ro_dst)->sin6_scope_id =
487 					    IN6_IS_SCOPE_EMBED(faddr) ? fifscope : IFSCOPE_NONE;
488 				}
489 				rtalloc_scoped(&in6p->inp_route, ip6oa.ip6oa_boundif);
490 
491 				inp_update_necp_policy(in6p, (struct sockaddr *)&from,
492 				    (struct sockaddr *)&to, ip6oa.ip6oa_boundif);
493 				in6p->inp_policyresult.results.qos_marking_gencount = 0;
494 			}
495 
496 			if (!necp_socket_is_allowed_to_send_recv_v6(in6p, in6p->in6p_lport, fport, laddr, faddr, NULL, 0, &policy_id, &route_rule_id, &skip_policy_id, &pass_flags)) {
497 				error = EHOSTUNREACH;
498 				goto release;
499 			}
500 
501 			necp_mark_packet_from_socket(m, in6p, policy_id, route_rule_id, skip_policy_id, pass_flags);
502 
503 			if (net_qos_policy_restricted != 0) {
504 				necp_socket_update_qos_marking(in6p, in6p->in6p_route.ro_rt, route_rule_id);
505 			}
506 		}
507 #endif /* NECP */
508 		if ((so->so_flags1 & SOF1_QOSMARKING_ALLOWED)) {
509 			ip6oa.ip6oa_flags |= IP6OAF_QOSMARKING_ALLOWED;
510 		}
511 		if (check_qos_marking_again) {
512 			ip6oa.ip6oa_flags |= IP6OAF_REDO_QOSMARKING_POLICY;
513 		}
514 		ip6oa.qos_marking_gencount = in6p->inp_policyresult.results.qos_marking_gencount;
515 
516 #if IPSEC
517 		if (in6p->in6p_sp != NULL && ipsec_setsocket(m, so) != 0) {
518 			error = ENOBUFS;
519 			goto release;
520 		}
521 #endif /*IPSEC*/
522 
523 		/* In case of IPv4-mapped address used in previous send */
524 		if (ROUTE_UNUSABLE(&in6p->in6p_route) ||
525 		    rt_key(in6p->in6p_route.ro_rt)->sa_family != AF_INET6) {
526 			ROUTE_RELEASE(&in6p->in6p_route);
527 		}
528 
529 		/* Copy the cached route and take an extra reference */
530 		in6p_route_copyout(in6p, &ro);
531 
532 		set_packet_service_class(m, so, sotc, PKT_SCF_IPV6);
533 
534 		m->m_pkthdr.pkt_flowsrc = FLOWSRC_INPCB;
535 		m->m_pkthdr.pkt_flowid = in6p->inp_flowhash;
536 		m->m_pkthdr.pkt_proto = IPPROTO_UDP;
537 		m->m_pkthdr.pkt_flags |= (PKTF_FLOW_ID | PKTF_FLOW_LOCALSRC);
538 		if (flowadv) {
539 			m->m_pkthdr.pkt_flags |= PKTF_FLOW_ADV;
540 		}
541 		m->m_pkthdr.tx_udp_pid = so->last_pid;
542 		if (so->so_flags & SOF_DELEGATED) {
543 			m->m_pkthdr.tx_udp_e_pid = so->e_pid;
544 		} else {
545 			m->m_pkthdr.tx_udp_e_pid = 0;
546 		}
547 #if (DEBUG || DEVELOPMENT)
548 		if (so->so_flags & SOF_MARK_WAKE_PKT) {
549 			so->so_flags &= ~SOF_MARK_WAKE_PKT;
550 			m->m_pkthdr.pkt_flags |= PKTF_WAKE_PKT;
551 		}
552 #endif /* (DEBUG || DEVELOPMENT) */
553 
554 		im6o = in6p->in6p_moptions;
555 		if (im6o != NULL) {
556 			IM6O_LOCK(im6o);
557 			IM6O_ADDREF_LOCKED(im6o);
558 			if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
559 			    im6o->im6o_multicast_ifp != NULL) {
560 				in6p->in6p_last_outifp =
561 				    im6o->im6o_multicast_ifp;
562 #if SKYWALK
563 				if (NETNS_TOKEN_VALID(&in6p->inp_netns_token)) {
564 					netns_set_ifnet(&in6p->inp_netns_token,
565 					    in6p->in6p_last_outifp);
566 				}
567 #endif /* SKYWALK */
568 			}
569 			IM6O_UNLOCK(im6o);
570 		}
571 
572 		ip6_output_setdstifscope(m, fifscope, NULL);
573 		ip6_output_setsrcifscope(m, lifscope, NULL);
574 
575 		socket_unlock(so, 0);
576 		error = ip6_output(m, optp, &ro, flags, im6o, NULL, &ip6oa);
577 		m = NULL;
578 		socket_lock(so, 0);
579 
580 		if (im6o != NULL) {
581 			IM6O_REMREF(im6o);
582 		}
583 
584 		if (check_qos_marking_again) {
585 			in6p->inp_policyresult.results.qos_marking_gencount = ip6oa.qos_marking_gencount;
586 			if (ip6oa.ip6oa_flags & IP6OAF_QOSMARKING_ALLOWED) {
587 				in6p->inp_socket->so_flags1 |= SOF1_QOSMARKING_ALLOWED;
588 			} else {
589 				in6p->inp_socket->so_flags1 &= ~SOF1_QOSMARKING_ALLOWED;
590 			}
591 		}
592 
593 		if (error == 0 && nstat_collect) {
594 			boolean_t cell, wifi, wired;
595 
596 			if (in6p->in6p_route.ro_rt != NULL) {
597 				cell = IFNET_IS_CELLULAR(in6p->in6p_route.
598 				    ro_rt->rt_ifp);
599 				wifi = (!cell && IFNET_IS_WIFI(in6p->in6p_route.
600 				    ro_rt->rt_ifp));
601 				wired = (!wifi && IFNET_IS_WIRED(in6p->in6p_route.
602 				    ro_rt->rt_ifp));
603 			} else {
604 				cell = wifi = wired = FALSE;
605 			}
606 			INP_ADD_STAT(in6p, cell, wifi, wired, txpackets, 1);
607 			INP_ADD_STAT(in6p, cell, wifi, wired, txbytes, ulen);
608 			inp_set_activity_bitmap(in6p);
609 		}
610 
611 		if (flowadv && (adv->code == FADV_FLOW_CONTROLLED ||
612 		    adv->code == FADV_SUSPENDED)) {
613 			/*
614 			 * Return an error to indicate
615 			 * that the packet has been dropped.
616 			 */
617 			error = ENOBUFS;
618 			inp_set_fc_state(in6p, adv->code);
619 		}
620 
621 		if (ro.ro_rt != NULL) {
622 			struct ifnet *outif = ro.ro_rt->rt_ifp;
623 
624 			so->so_pktheadroom = (uint16_t)P2ROUNDUP(
625 				sizeof(struct udphdr) +
626 				hlen +
627 				ifnet_hdrlen(outif) +
628 				ifnet_mbuf_packetpreamblelen(outif),
629 				sizeof(u_int32_t));
630 		}
631 
632 		/* Synchronize PCB cached route */
633 		in6p_route_copyin(in6p, &ro);
634 
635 		if (in6p->in6p_route.ro_rt != NULL) {
636 			struct rtentry *rt = in6p->in6p_route.ro_rt;
637 			struct ifnet *outif;
638 
639 			if (rt->rt_flags & RTF_MULTICAST) {
640 				rt = NULL;      /* unusable */
641 			}
642 #if CONTENT_FILTER
643 			/*
644 			 * Discard temporary route for cfil case
645 			 */
646 			if (cfil_faddr_use) {
647 				rt = NULL;      /* unusable */
648 			}
649 #endif
650 
651 			/*
652 			 * Always discard the cached route for unconnected
653 			 * socket or if it is a multicast route.
654 			 */
655 			if (rt == NULL) {
656 				ROUTE_RELEASE(&in6p->in6p_route);
657 			}
658 
659 			/*
660 			 * If the destination route is unicast, update outif
661 			 * with that of the route interface used by IP.
662 			 */
663 			if (rt != NULL) {
664 				/*
665 				 * When an NECP IP tunnel policy forces the outbound interface,
666 				 * ip6_output_list() informs the transport layer what is the actual
667 				 * outgoing interface
668 				 */
669 				if (ip6oa.ip6oa_flags & IP6OAF_BOUND_IF) {
670 					outif = ifindex2ifnet[ip6oa.ip6oa_boundif];
671 				} else {
672 					outif = rt->rt_ifp;
673 				}
674 				if (outif != NULL && outif != in6p->in6p_last_outifp) {
675 					in6p->in6p_last_outifp = outif;
676 #if SKYWALK
677 					if (NETNS_TOKEN_VALID(&in6p->inp_netns_token)) {
678 						netns_set_ifnet(&in6p->inp_netns_token,
679 						    in6p->in6p_last_outifp);
680 					}
681 #endif /* SKYWALK */
682 
683 					so->so_pktheadroom = (uint16_t)P2ROUNDUP(
684 						sizeof(struct udphdr) +
685 						hlen +
686 						ifnet_hdrlen(outif) +
687 						ifnet_mbuf_packetpreamblelen(outif),
688 						sizeof(u_int32_t));
689 				}
690 			}
691 		} else {
692 			ROUTE_RELEASE(&in6p->in6p_route);
693 		}
694 
695 		/*
696 		 * If output interface was cellular/expensive, and this
697 		 * socket is denied access to it, generate an event.
698 		 */
699 		if (error != 0 && (ip6oa.ip6oa_flags & IP6OAF_R_IFDENIED) &&
700 		    (INP_NO_CELLULAR(in6p) || INP_NO_EXPENSIVE(in6p) || INP_NO_CONSTRAINED(in6p))) {
701 			soevent(in6p->inp_socket, (SO_FILT_HINT_LOCKED |
702 			    SO_FILT_HINT_IFDENIED));
703 		}
704 		break;
705 	case AF_INET:
706 		error = EAFNOSUPPORT;
707 		goto release;
708 	}
709 	goto releaseopt;
710 
711 release:
712 
713 	if (m != NULL) {
714 		m_freem(m);
715 	}
716 
717 releaseopt:
718 	if (control != NULL) {
719 		if (optp == &opt) {
720 			ip6_clearpktopts(optp, -1);
721 		}
722 		m_freem(control);
723 	}
724 #if CONTENT_FILTER
725 	if (cfil_tag) {
726 		m_tag_free(cfil_tag);
727 	}
728 #endif
729 	if (sndinprog_cnt_used) {
730 		VERIFY(in6p->inp_sndinprog_cnt > 0);
731 		if (--in6p->inp_sndinprog_cnt == 0) {
732 			in6p->inp_flags &= ~(INP_FC_FEEDBACK);
733 			if (in6p->inp_sndingprog_waiters > 0) {
734 				wakeup(&in6p->inp_sndinprog_cnt);
735 			}
736 		}
737 		sndinprog_cnt_used = false;
738 	}
739 
740 	return error;
741 }
742