xref: /xnu-8796.101.5/bsd/netinet/udp_usrreq.c (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
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  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
30  *	The Regents of the University of California.  All rights reserved.
31  *
32  * Redistribution and use in source and binary forms, with or without
33  * modification, are permitted provided that the following conditions
34  * are met:
35  * 1. Redistributions of source code must retain the above copyright
36  *    notice, this list of conditions and the following disclaimer.
37  * 2. Redistributions in binary form must reproduce the above copyright
38  *    notice, this list of conditions and the following disclaimer in the
39  *    documentation and/or other materials provided with the distribution.
40  * 3. All advertising materials mentioning features or use of this software
41  *    must display the following acknowledgement:
42  *	This product includes software developed by the University of
43  *	California, Berkeley and its contributors.
44  * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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  *	@(#)udp_usrreq.c	8.6 (Berkeley) 5/23/95
61  */
62 
63 #include <sys/param.h>
64 #include <sys/systm.h>
65 #include <sys/kernel.h>
66 #include <sys/malloc.h>
67 #include <sys/mbuf.h>
68 #include <sys/domain.h>
69 #include <sys/protosw.h>
70 #include <sys/socket.h>
71 #include <sys/socketvar.h>
72 #include <sys/sysctl.h>
73 #include <sys/syslog.h>
74 #include <sys/mcache.h>
75 #include <net/ntstat.h>
76 
77 #include <kern/zalloc.h>
78 #include <mach/boolean.h>
79 
80 #include <net/if.h>
81 #include <net/if_types.h>
82 #include <net/route.h>
83 #include <net/dlil.h>
84 #include <net/net_api_stats.h>
85 
86 #include <netinet/in.h>
87 #include <netinet/in_systm.h>
88 #include <netinet/in_tclass.h>
89 #include <netinet/ip.h>
90 #include <netinet/ip6.h>
91 #include <netinet/in_pcb.h>
92 #include <netinet/in_var.h>
93 #include <netinet/ip_var.h>
94 #include <netinet6/in6_pcb.h>
95 #include <netinet6/ip6_var.h>
96 #include <netinet6/udp6_var.h>
97 #include <netinet/ip_icmp.h>
98 #include <netinet/icmp_var.h>
99 #include <netinet/udp.h>
100 #include <netinet/udp_var.h>
101 #include <sys/kdebug.h>
102 
103 #if IPSEC
104 #include <netinet6/ipsec.h>
105 #include <netinet6/esp.h>
106 #include <netkey/key.h>
107 extern int ipsec_bypass;
108 extern int esp_udp_encap_port;
109 #endif /* IPSEC */
110 
111 #if NECP
112 #include <net/necp.h>
113 #endif /* NECP */
114 
115 #if FLOW_DIVERT
116 #include <netinet/flow_divert.h>
117 #endif /* FLOW_DIVERT */
118 
119 #if CONTENT_FILTER
120 #include <net/content_filter.h>
121 #endif /* CONTENT_FILTER */
122 
123 #if SKYWALK
124 #include <skywalk/core/skywalk_var.h>
125 #endif /* SKYWALK */
126 
127 #define DBG_LAYER_IN_BEG        NETDBG_CODE(DBG_NETUDP, 0)
128 #define DBG_LAYER_IN_END        NETDBG_CODE(DBG_NETUDP, 2)
129 #define DBG_LAYER_OUT_BEG       NETDBG_CODE(DBG_NETUDP, 1)
130 #define DBG_LAYER_OUT_END       NETDBG_CODE(DBG_NETUDP, 3)
131 #define DBG_FNC_UDP_INPUT       NETDBG_CODE(DBG_NETUDP, (5 << 8))
132 #define DBG_FNC_UDP_OUTPUT      NETDBG_CODE(DBG_NETUDP, (6 << 8) | 1)
133 
134 /*
135  * UDP protocol implementation.
136  * Per RFC 768, August, 1980.
137  */
138 #ifndef COMPAT_42
139 static int udpcksum = 1;
140 #else
141 static int udpcksum = 0;                /* XXX */
142 #endif
143 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum,
144     CTLFLAG_RW | CTLFLAG_LOCKED, &udpcksum, 0, "");
145 
146 int udp_log_in_vain = 0;
147 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW | CTLFLAG_LOCKED,
148     &udp_log_in_vain, 0, "Log all incoming UDP packets");
149 
150 static int blackhole = 0;
151 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW | CTLFLAG_LOCKED,
152     &blackhole, 0, "Do not send port unreachables for refused connects");
153 
154 static KALLOC_TYPE_DEFINE(inpcbzone, struct inpcb, NET_KT_DEFAULT);
155 
156 struct inpcbhead udb;           /* from udp_var.h */
157 #define udb6    udb  /* for KAME src sync over BSD*'s */
158 struct inpcbinfo udbinfo;
159 
160 #ifndef UDBHASHSIZE
161 #define UDBHASHSIZE 16
162 #endif
163 
164 /* Garbage collection performed during most recent udp_gc() run */
165 static boolean_t udp_gc_done = FALSE;
166 
167 #define log_in_vain_log(a) { log a; }
168 
169 static int udp_getstat SYSCTL_HANDLER_ARGS;
170 struct  udpstat udpstat;        /* from udp_var.h */
171 SYSCTL_PROC(_net_inet_udp, UDPCTL_STATS, stats,
172     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
173     0, 0, udp_getstat, "S,udpstat",
174     "UDP statistics (struct udpstat, netinet/udp_var.h)");
175 
176 SYSCTL_INT(_net_inet_udp, OID_AUTO, pcbcount,
177     CTLFLAG_RD | CTLFLAG_LOCKED, &udbinfo.ipi_count, 0,
178     "Number of active PCBs");
179 
180 __private_extern__ int udp_use_randomport = 1;
181 SYSCTL_INT(_net_inet_udp, OID_AUTO, randomize_ports,
182     CTLFLAG_RW | CTLFLAG_LOCKED, &udp_use_randomport, 0,
183     "Randomize UDP port numbers");
184 
185 struct udp_in6 {
186 	struct sockaddr_in6     uin6_sin;
187 	u_char                  uin6_init_done : 1;
188 };
189 struct udp_ip6 {
190 	struct ip6_hdr          uip6_ip6;
191 	u_char                  uip6_init_done : 1;
192 };
193 
194 int udp_abort(struct socket *);
195 int udp_attach(struct socket *, int, struct proc *);
196 int udp_bind(struct socket *, struct sockaddr *, struct proc *);
197 int udp_connect(struct socket *, struct sockaddr *, struct proc *);
198 int udp_connectx(struct socket *, struct sockaddr *,
199     struct sockaddr *, struct proc *, uint32_t, sae_associd_t,
200     sae_connid_t *, uint32_t, void *, uint32_t, struct uio *, user_ssize_t *);
201 int udp_detach(struct socket *);
202 int udp_disconnect(struct socket *);
203 int udp_disconnectx(struct socket *, sae_associd_t, sae_connid_t);
204 int udp_send(struct socket *, int, struct mbuf *, struct sockaddr *,
205     struct mbuf *, struct proc *);
206 static void udp_append(struct inpcb *, struct ip *, struct mbuf *, int,
207     struct sockaddr_in *, struct udp_in6 *, struct udp_ip6 *, struct ifnet *);
208 static int udp_input_checksum(struct mbuf *, struct udphdr *, int, int);
209 int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
210     struct mbuf *, struct proc *);
211 static void ip_2_ip6_hdr(struct ip6_hdr *ip6, struct ip *ip);
212 static void udp_gc(struct inpcbinfo *);
213 static int udp_defunct(struct socket *);
214 
215 struct pr_usrreqs udp_usrreqs = {
216 	.pru_abort =            udp_abort,
217 	.pru_attach =           udp_attach,
218 	.pru_bind =             udp_bind,
219 	.pru_connect =          udp_connect,
220 	.pru_connectx =         udp_connectx,
221 	.pru_control =          in_control,
222 	.pru_detach =           udp_detach,
223 	.pru_disconnect =       udp_disconnect,
224 	.pru_disconnectx =      udp_disconnectx,
225 	.pru_peeraddr =         in_getpeeraddr,
226 	.pru_send =             udp_send,
227 	.pru_shutdown =         udp_shutdown,
228 	.pru_sockaddr =         in_getsockaddr,
229 	.pru_sosend =           sosend,
230 	.pru_soreceive =        soreceive,
231 	.pru_soreceive_list =   soreceive_list,
232 	.pru_defunct =          udp_defunct,
233 };
234 
235 void
udp_init(struct protosw * pp,struct domain * dp)236 udp_init(struct protosw *pp, struct domain *dp)
237 {
238 #pragma unused(dp)
239 	static int udp_initialized = 0;
240 	struct inpcbinfo        *pcbinfo;
241 
242 	VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED);
243 
244 	if (udp_initialized) {
245 		return;
246 	}
247 	udp_initialized = 1;
248 	uint32_t pool_size = (nmbclusters << MCLSHIFT) >> MBSHIFT;
249 	if (pool_size >= 96) {
250 		/* Improves 10GbE UDP performance. */
251 		udp_recvspace = 786896;
252 	}
253 	LIST_INIT(&udb);
254 	udbinfo.ipi_listhead = &udb;
255 	udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB,
256 	    &udbinfo.ipi_hashmask);
257 	udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB,
258 	    &udbinfo.ipi_porthashmask);
259 	udbinfo.ipi_zone.zov_kt_heap = inpcbzone;
260 
261 	pcbinfo = &udbinfo;
262 	/*
263 	 * allocate lock group and attribute for udp pcb mutexes
264 	 */
265 	pcbinfo->ipi_lock_grp = lck_grp_alloc_init("udppcb",
266 	    LCK_GRP_ATTR_NULL);
267 	lck_attr_setdefault(&pcbinfo->ipi_lock_attr);
268 	lck_rw_init(&pcbinfo->ipi_lock, pcbinfo->ipi_lock_grp,
269 	    &pcbinfo->ipi_lock_attr);
270 
271 	udbinfo.ipi_gc = udp_gc;
272 	in_pcbinfo_attach(&udbinfo);
273 }
274 
275 void
udp_input(struct mbuf * m,int iphlen)276 udp_input(struct mbuf *m, int iphlen)
277 {
278 	struct ip *ip;
279 	struct udphdr *uh;
280 	struct inpcb *inp;
281 	struct mbuf *opts = NULL;
282 	int len, isbroadcast;
283 	struct ip save_ip;
284 	struct sockaddr *append_sa;
285 	struct inpcbinfo *pcbinfo = &udbinfo;
286 	struct sockaddr_in udp_in;
287 	struct ip_moptions *imo = NULL;
288 	int foundmembership = 0, ret = 0;
289 	struct udp_in6 udp_in6;
290 	struct udp_ip6 udp_ip6;
291 	struct ifnet *ifp = m->m_pkthdr.rcvif;
292 	boolean_t cell = IFNET_IS_CELLULAR(ifp);
293 	boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp));
294 	boolean_t wired = (!wifi && IFNET_IS_WIRED(ifp));
295 	u_int16_t pf_tag = 0;
296 	boolean_t is_wake_pkt = false;
297 
298 	bzero(&udp_in, sizeof(udp_in));
299 	udp_in.sin_len = sizeof(struct sockaddr_in);
300 	udp_in.sin_family = AF_INET;
301 	bzero(&udp_in6, sizeof(udp_in6));
302 	udp_in6.uin6_sin.sin6_len = sizeof(struct sockaddr_in6);
303 	udp_in6.uin6_sin.sin6_family = AF_INET6;
304 
305 	if (m->m_flags & M_PKTHDR) {
306 		pf_tag = m_pftag(m)->pftag_tag;
307 		if (m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT) {
308 			is_wake_pkt = true;
309 		}
310 	}
311 
312 	udpstat.udps_ipackets++;
313 
314 	KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_START, 0, 0, 0, 0, 0);
315 
316 	/* Expect 32-bit aligned data pointer on strict-align platforms */
317 	MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
318 
319 	m_add_crumb(m, PKT_CRUMB_UDP_INPUT);
320 
321 	/*
322 	 * Strip IP options, if any; should skip this,
323 	 * make available to user, and use on returned packets,
324 	 * but we don't yet have a way to check the checksum
325 	 * with options still present.
326 	 */
327 	if (iphlen > sizeof(struct ip)) {
328 		ip_stripoptions(m);
329 		iphlen = sizeof(struct ip);
330 	}
331 
332 	/*
333 	 * Get IP and UDP header together in first mbuf.
334 	 */
335 	ip = mtod(m, struct ip *);
336 	if (m->m_len < iphlen + sizeof(struct udphdr)) {
337 		m = m_pullup(m, iphlen + sizeof(struct udphdr));
338 		if (m == NULL) {
339 			udpstat.udps_hdrops++;
340 			KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END,
341 			    0, 0, 0, 0, 0);
342 			return;
343 		}
344 		ip = mtod(m, struct ip *);
345 	}
346 	uh = (struct udphdr *)(void *)((caddr_t)ip + iphlen);
347 
348 	/* destination port of 0 is illegal, based on RFC768. */
349 	if (uh->uh_dport == 0) {
350 		IF_UDP_STATINC(ifp, port0);
351 		goto bad;
352 	}
353 
354 	KERNEL_DEBUG(DBG_LAYER_IN_BEG, uh->uh_dport, uh->uh_sport,
355 	    ip->ip_src.s_addr, ip->ip_dst.s_addr, uh->uh_ulen);
356 
357 	/*
358 	 * Make mbuf data length reflect UDP length.
359 	 * If not enough data to reflect UDP length, drop.
360 	 */
361 	len = ntohs((u_short)uh->uh_ulen);
362 	if (ip->ip_len != len) {
363 		if (len > ip->ip_len || len < sizeof(struct udphdr)) {
364 			udpstat.udps_badlen++;
365 			IF_UDP_STATINC(ifp, badlength);
366 			goto bad;
367 		}
368 		m_adj(m, len - ip->ip_len);
369 		/* ip->ip_len = len; */
370 	}
371 	/*
372 	 * Save a copy of the IP header in case we want restore it
373 	 * for sending an ICMP error message in response.
374 	 */
375 	save_ip = *ip;
376 
377 	/*
378 	 * Checksum extended UDP header and data.
379 	 */
380 	if (udp_input_checksum(m, uh, iphlen, len)) {
381 		goto bad;
382 	}
383 
384 	isbroadcast = in_broadcast(ip->ip_dst, ifp);
385 
386 	if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || isbroadcast) {
387 		int reuse_sock = 0, mcast_delivered = 0;
388 
389 		lck_rw_lock_shared(&pcbinfo->ipi_lock);
390 		/*
391 		 * Deliver a multicast or broadcast datagram to *all* sockets
392 		 * for which the local and remote addresses and ports match
393 		 * those of the incoming datagram.  This allows more than
394 		 * one process to receive multi/broadcasts on the same port.
395 		 * (This really ought to be done for unicast datagrams as
396 		 * well, but that would cause problems with existing
397 		 * applications that open both address-specific sockets and
398 		 * a wildcard socket listening to the same port -- they would
399 		 * end up receiving duplicates of every unicast datagram.
400 		 * Those applications open the multiple sockets to overcome an
401 		 * inadequacy of the UDP socket interface, but for backwards
402 		 * compatibility we avoid the problem here rather than
403 		 * fixing the interface.  Maybe 4.5BSD will remedy this?)
404 		 */
405 
406 		/*
407 		 * Construct sockaddr format source address.
408 		 */
409 		udp_in.sin_port = uh->uh_sport;
410 		udp_in.sin_addr = ip->ip_src;
411 		/*
412 		 * Locate pcb(s) for datagram.
413 		 * (Algorithm copied from raw_intr().)
414 		 */
415 		udp_in6.uin6_init_done = udp_ip6.uip6_init_done = 0;
416 		LIST_FOREACH(inp, &udb, inp_list) {
417 #if IPSEC
418 			int skipit;
419 #endif /* IPSEC */
420 
421 			if (inp->inp_socket == NULL) {
422 				continue;
423 			}
424 			if (inp != sotoinpcb(inp->inp_socket)) {
425 				panic("%s: bad so back ptr inp=%p",
426 				    __func__, inp);
427 				/* NOTREACHED */
428 			}
429 			if ((inp->inp_vflag & INP_IPV4) == 0) {
430 				continue;
431 			}
432 			if (inp_restricted_recv(inp, ifp)) {
433 				continue;
434 			}
435 
436 			if ((inp->inp_moptions == NULL) &&
437 			    (ntohl(ip->ip_dst.s_addr) !=
438 			    INADDR_ALLHOSTS_GROUP) && (isbroadcast == 0)) {
439 				continue;
440 			}
441 			/*
442 			 * Skip unbound sockets before taking the lock on the socket as
443 			 * the test with the destination port in the header will fail
444 			 */
445 			if (inp->inp_lport == 0) {
446 				continue;
447 			}
448 
449 			if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) ==
450 			    WNT_STOPUSING) {
451 				continue;
452 			}
453 
454 			udp_lock(inp->inp_socket, 1, 0);
455 
456 			if (in_pcb_checkstate(inp, WNT_RELEASE, 1) ==
457 			    WNT_STOPUSING) {
458 				udp_unlock(inp->inp_socket, 1, 0);
459 				continue;
460 			}
461 
462 			if (inp->inp_lport != uh->uh_dport) {
463 				udp_unlock(inp->inp_socket, 1, 0);
464 				continue;
465 			}
466 			if (inp->inp_laddr.s_addr != INADDR_ANY) {
467 				if (inp->inp_laddr.s_addr !=
468 				    ip->ip_dst.s_addr) {
469 					udp_unlock(inp->inp_socket, 1, 0);
470 					continue;
471 				}
472 			}
473 			if (inp->inp_faddr.s_addr != INADDR_ANY) {
474 				if (inp->inp_faddr.s_addr !=
475 				    ip->ip_src.s_addr ||
476 				    inp->inp_fport != uh->uh_sport) {
477 					udp_unlock(inp->inp_socket, 1, 0);
478 					continue;
479 				}
480 			}
481 
482 			if (isbroadcast == 0 && (ntohl(ip->ip_dst.s_addr) !=
483 			    INADDR_ALLHOSTS_GROUP)) {
484 				struct sockaddr_in group;
485 				int blocked;
486 
487 				if ((imo = inp->inp_moptions) == NULL) {
488 					udp_unlock(inp->inp_socket, 1, 0);
489 					continue;
490 				}
491 				IMO_LOCK(imo);
492 
493 				bzero(&group, sizeof(struct sockaddr_in));
494 				group.sin_len = sizeof(struct sockaddr_in);
495 				group.sin_family = AF_INET;
496 				group.sin_addr = ip->ip_dst;
497 
498 				blocked = imo_multi_filter(imo, ifp,
499 				    &group, &udp_in);
500 				if (blocked == MCAST_PASS) {
501 					foundmembership = 1;
502 				}
503 
504 				IMO_UNLOCK(imo);
505 				if (!foundmembership) {
506 					udp_unlock(inp->inp_socket, 1, 0);
507 					if (blocked == MCAST_NOTSMEMBER ||
508 					    blocked == MCAST_MUTED) {
509 						udpstat.udps_filtermcast++;
510 					}
511 					continue;
512 				}
513 				foundmembership = 0;
514 			}
515 
516 			reuse_sock = (inp->inp_socket->so_options &
517 			    (SO_REUSEPORT | SO_REUSEADDR));
518 
519 #if NECP
520 			skipit = 0;
521 			if (!necp_socket_is_allowed_to_send_recv_v4(inp,
522 			    uh->uh_dport, uh->uh_sport, &ip->ip_dst,
523 			    &ip->ip_src, ifp, pf_tag, NULL, NULL, NULL, NULL)) {
524 				/* do not inject data to pcb */
525 				skipit = 1;
526 			}
527 			if (skipit == 0)
528 #endif /* NECP */
529 			{
530 				struct mbuf *n = NULL;
531 
532 				if (reuse_sock) {
533 					n = m_copy(m, 0, M_COPYALL);
534 				}
535 				udp_append(inp, ip, m,
536 				    iphlen + sizeof(struct udphdr),
537 				    &udp_in, &udp_in6, &udp_ip6, ifp);
538 				mcast_delivered++;
539 
540 				m = n;
541 			}
542 			if (is_wake_pkt) {
543 				soevent(inp->inp_socket, SO_FILT_HINT_LOCKED | SO_FILT_HINT_WAKE_PKT);
544 			}
545 
546 			udp_unlock(inp->inp_socket, 1, 0);
547 
548 
549 			/*
550 			 * Don't look for additional matches if this one does
551 			 * not have either the SO_REUSEPORT or SO_REUSEADDR
552 			 * socket options set.  This heuristic avoids searching
553 			 * through all pcbs in the common case of a non-shared
554 			 * port.  It assumes that an application will never
555 			 * clear these options after setting them.
556 			 */
557 			if (reuse_sock == 0 || m == NULL) {
558 				break;
559 			}
560 
561 			/*
562 			 * Expect 32-bit aligned data pointer on strict-align
563 			 * platforms.
564 			 */
565 			MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
566 			/*
567 			 * Recompute IP and UDP header pointers for new mbuf
568 			 */
569 			ip = mtod(m, struct ip *);
570 			uh = (struct udphdr *)(void *)((caddr_t)ip + iphlen);
571 		}
572 		lck_rw_done(&pcbinfo->ipi_lock);
573 
574 		if (mcast_delivered == 0) {
575 			/*
576 			 * No matching pcb found; discard datagram.
577 			 * (No need to send an ICMP Port Unreachable
578 			 * for a broadcast or multicast datgram.)
579 			 */
580 			udpstat.udps_noportbcast++;
581 			IF_UDP_STATINC(ifp, port_unreach);
582 			goto bad;
583 		}
584 
585 		/* free the extra copy of mbuf or skipped by IPsec */
586 		if (m != NULL) {
587 			m_freem(m);
588 		}
589 		KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0);
590 		return;
591 	}
592 
593 #if IPSEC
594 	/*
595 	 * UDP to port 4500 with a payload where the first four bytes are
596 	 * not zero is a UDP encapsulated IPsec packet. Packets where
597 	 * the payload is one byte and that byte is 0xFF are NAT keepalive
598 	 * packets. Decapsulate the ESP packet and carry on with IPsec input
599 	 * or discard the NAT keep-alive.
600 	 */
601 	if (ipsec_bypass == 0 && (esp_udp_encap_port & 0xFFFF) != 0 &&
602 	    (uh->uh_dport == ntohs((u_short)esp_udp_encap_port) ||
603 	    uh->uh_sport == ntohs((u_short)esp_udp_encap_port))) {
604 		/*
605 		 * Check if ESP or keepalive:
606 		 *      1. If the destination port of the incoming packet is 4500.
607 		 *      2. If the source port of the incoming packet is 4500,
608 		 *         then check the SADB to match IP address and port.
609 		 */
610 		bool check_esp = true;
611 		if (uh->uh_dport != ntohs((u_short)esp_udp_encap_port)) {
612 			check_esp = key_checksa_present(AF_INET, (caddr_t)&ip->ip_dst,
613 			    (caddr_t)&ip->ip_src, uh->uh_dport,
614 			    uh->uh_sport, IFSCOPE_NONE, IFSCOPE_NONE);
615 		}
616 
617 		if (check_esp) {
618 			int payload_len = len - sizeof(struct udphdr) > 4 ? 4 :
619 			    len - sizeof(struct udphdr);
620 
621 			if (m->m_len < iphlen + sizeof(struct udphdr) + payload_len) {
622 				if ((m = m_pullup(m, iphlen + sizeof(struct udphdr) +
623 				    payload_len)) == NULL) {
624 					udpstat.udps_hdrops++;
625 					KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END,
626 					    0, 0, 0, 0, 0);
627 					return;
628 				}
629 				/*
630 				 * Expect 32-bit aligned data pointer on strict-align
631 				 * platforms.
632 				 */
633 				MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
634 
635 				ip = mtod(m, struct ip *);
636 				uh = (struct udphdr *)(void *)((caddr_t)ip + iphlen);
637 			}
638 			/* Check for NAT keepalive packet */
639 			if (payload_len == 1 && *(u_int8_t *)
640 			    ((caddr_t)uh + sizeof(struct udphdr)) == 0xFF) {
641 				m_freem(m);
642 				KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END,
643 				    0, 0, 0, 0, 0);
644 				return;
645 			} else if (payload_len == 4 && *(u_int32_t *)(void *)
646 			    ((caddr_t)uh + sizeof(struct udphdr)) != 0) {
647 				/* UDP encapsulated IPsec packet to pass through NAT */
648 				KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END,
649 				    0, 0, 0, 0, 0);
650 				/* preserve the udp header */
651 				esp4_input(m, iphlen + sizeof(struct udphdr));
652 				return;
653 			}
654 		}
655 	}
656 #endif /* IPSEC */
657 
658 	/*
659 	 * Locate pcb for datagram.
660 	 */
661 	inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport,
662 	    ip->ip_dst, uh->uh_dport, 1, ifp);
663 	if (inp == NULL) {
664 		IF_UDP_STATINC(ifp, port_unreach);
665 
666 		if (udp_log_in_vain) {
667 			char buf[MAX_IPv4_STR_LEN];
668 			char buf2[MAX_IPv4_STR_LEN];
669 
670 			/* check src and dst address */
671 			if (udp_log_in_vain < 3) {
672 				log(LOG_INFO, "Connection attempt to "
673 				    "UDP %s:%d from %s:%d\n", inet_ntop(AF_INET,
674 				    &ip->ip_dst, buf, sizeof(buf)),
675 				    ntohs(uh->uh_dport), inet_ntop(AF_INET,
676 				    &ip->ip_src, buf2, sizeof(buf2)),
677 				    ntohs(uh->uh_sport));
678 			} else if (!(m->m_flags & (M_BCAST | M_MCAST)) &&
679 			    ip->ip_dst.s_addr != ip->ip_src.s_addr) {
680 				log_in_vain_log((LOG_INFO,
681 				    "Stealth Mode connection attempt to "
682 				    "UDP %s:%d from %s:%d\n", inet_ntop(AF_INET,
683 				    &ip->ip_dst, buf, sizeof(buf)),
684 				    ntohs(uh->uh_dport), inet_ntop(AF_INET,
685 				    &ip->ip_src, buf2, sizeof(buf2)),
686 				    ntohs(uh->uh_sport)))
687 			}
688 		}
689 		udpstat.udps_noport++;
690 		if (m->m_flags & (M_BCAST | M_MCAST)) {
691 			udpstat.udps_noportbcast++;
692 			goto bad;
693 		}
694 		if (blackhole) {
695 			if (ifp && ifp->if_type != IFT_LOOP) {
696 				goto bad;
697 			}
698 		}
699 		*ip = save_ip;
700 		ip->ip_len += iphlen;
701 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
702 		KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0);
703 		return;
704 	}
705 	udp_lock(inp->inp_socket, 1, 0);
706 
707 	if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) {
708 		udp_unlock(inp->inp_socket, 1, 0);
709 		IF_UDP_STATINC(ifp, cleanup);
710 		goto bad;
711 	}
712 #if NECP
713 	if (!necp_socket_is_allowed_to_send_recv_v4(inp, uh->uh_dport,
714 	    uh->uh_sport, &ip->ip_dst, &ip->ip_src, ifp, pf_tag, NULL, NULL, NULL, NULL)) {
715 		udp_unlock(inp->inp_socket, 1, 0);
716 		IF_UDP_STATINC(ifp, badipsec);
717 		goto bad;
718 	}
719 #endif /* NECP */
720 
721 	/*
722 	 * Construct sockaddr format source address.
723 	 * Stuff source address and datagram in user buffer.
724 	 */
725 	udp_in.sin_port = uh->uh_sport;
726 	udp_in.sin_addr = ip->ip_src;
727 	if ((inp->inp_flags & INP_CONTROLOPTS) != 0 ||
728 	    SOFLOW_ENABLED(inp->inp_socket) ||
729 	    SO_RECV_CONTROL_OPTS(inp->inp_socket)) {
730 		if (inp->inp_vflag & INP_IPV6 || inp->inp_vflag & INP_V4MAPPEDV6) {
731 			int savedflags;
732 
733 			ip_2_ip6_hdr(&udp_ip6.uip6_ip6, ip);
734 			savedflags = inp->inp_flags;
735 			inp->inp_flags &= ~INP_UNMAPPABLEOPTS;
736 			ret = ip6_savecontrol(inp, m, &opts);
737 			inp->inp_flags = savedflags;
738 		} else {
739 			ret = ip_savecontrol(inp, &opts, ip, m);
740 		}
741 		if (ret != 0) {
742 			udp_unlock(inp->inp_socket, 1, 0);
743 			goto bad;
744 		}
745 	}
746 	m_adj(m, iphlen + sizeof(struct udphdr));
747 
748 	KERNEL_DEBUG(DBG_LAYER_IN_END, uh->uh_dport, uh->uh_sport,
749 	    save_ip.ip_src.s_addr, save_ip.ip_dst.s_addr, uh->uh_ulen);
750 
751 	if (inp->inp_vflag & INP_IPV6) {
752 		in6_sin_2_v4mapsin6(&udp_in, &udp_in6.uin6_sin);
753 		append_sa = (struct sockaddr *)&udp_in6.uin6_sin;
754 	} else {
755 		append_sa = (struct sockaddr *)&udp_in;
756 	}
757 	if (nstat_collect) {
758 		INP_ADD_STAT(inp, cell, wifi, wired, rxpackets, 1);
759 		INP_ADD_STAT(inp, cell, wifi, wired, rxbytes, m->m_pkthdr.len);
760 		inp_set_activity_bitmap(inp);
761 	}
762 	so_recv_data_stat(inp->inp_socket, m, 0);
763 	if (sbappendaddr(&inp->inp_socket->so_rcv, append_sa,
764 	    m, opts, NULL) == 0) {
765 		udpstat.udps_fullsock++;
766 	} else {
767 		sorwakeup(inp->inp_socket);
768 	}
769 	if (is_wake_pkt) {
770 		soevent(inp->inp_socket, SO_FILT_HINT_LOCKED | SO_FILT_HINT_WAKE_PKT);
771 	}
772 	udp_unlock(inp->inp_socket, 1, 0);
773 	KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0);
774 	return;
775 bad:
776 	m_freem(m);
777 	if (opts) {
778 		m_freem(opts);
779 	}
780 	KERNEL_DEBUG(DBG_FNC_UDP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0);
781 }
782 
783 static void
ip_2_ip6_hdr(struct ip6_hdr * ip6,struct ip * ip)784 ip_2_ip6_hdr(struct ip6_hdr *ip6, struct ip *ip)
785 {
786 	bzero(ip6, sizeof(*ip6));
787 
788 	ip6->ip6_vfc = IPV6_VERSION;
789 	ip6->ip6_plen = ip->ip_len;
790 	ip6->ip6_nxt = ip->ip_p;
791 	ip6->ip6_hlim = ip->ip_ttl;
792 	if (ip->ip_src.s_addr) {
793 		ip6->ip6_src.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
794 		ip6->ip6_src.s6_addr32[3] = ip->ip_src.s_addr;
795 	}
796 	if (ip->ip_dst.s_addr) {
797 		ip6->ip6_dst.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
798 		ip6->ip6_dst.s6_addr32[3] = ip->ip_dst.s_addr;
799 	}
800 }
801 
802 /*
803  * subroutine of udp_input(), mainly for source code readability.
804  */
805 static void
udp_append(struct inpcb * last,struct ip * ip,struct mbuf * n,int off,struct sockaddr_in * pudp_in,struct udp_in6 * pudp_in6,struct udp_ip6 * pudp_ip6,struct ifnet * ifp)806 udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, int off,
807     struct sockaddr_in *pudp_in, struct udp_in6 *pudp_in6,
808     struct udp_ip6 *pudp_ip6, struct ifnet *ifp)
809 {
810 	struct sockaddr *append_sa;
811 	struct mbuf *opts = 0;
812 	boolean_t cell = IFNET_IS_CELLULAR(ifp);
813 	boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp));
814 	boolean_t wired = (!wifi && IFNET_IS_WIRED(ifp));
815 	int ret = 0;
816 
817 	if ((last->inp_flags & INP_CONTROLOPTS) != 0 ||
818 	    SOFLOW_ENABLED(last->inp_socket) ||
819 	    SO_RECV_CONTROL_OPTS(last->inp_socket)) {
820 		if (last->inp_vflag & INP_IPV6 || last->inp_vflag & INP_V4MAPPEDV6) {
821 			int savedflags;
822 
823 			if (pudp_ip6->uip6_init_done == 0) {
824 				ip_2_ip6_hdr(&pudp_ip6->uip6_ip6, ip);
825 				pudp_ip6->uip6_init_done = 1;
826 			}
827 			savedflags = last->inp_flags;
828 			last->inp_flags &= ~INP_UNMAPPABLEOPTS;
829 			ret = ip6_savecontrol(last, n, &opts);
830 			if (ret != 0) {
831 				last->inp_flags = savedflags;
832 				goto error;
833 			}
834 			last->inp_flags = savedflags;
835 		} else {
836 			ret = ip_savecontrol(last, &opts, ip, n);
837 			if (ret != 0) {
838 				goto error;
839 			}
840 		}
841 	}
842 	if (last->inp_vflag & INP_IPV6) {
843 		if (pudp_in6->uin6_init_done == 0) {
844 			in6_sin_2_v4mapsin6(pudp_in, &pudp_in6->uin6_sin);
845 			pudp_in6->uin6_init_done = 1;
846 		}
847 		append_sa = (struct sockaddr *)&pudp_in6->uin6_sin;
848 	} else {
849 		append_sa = (struct sockaddr *)pudp_in;
850 	}
851 	if (nstat_collect) {
852 		INP_ADD_STAT(last, cell, wifi, wired, rxpackets, 1);
853 		INP_ADD_STAT(last, cell, wifi, wired, rxbytes,
854 		    n->m_pkthdr.len);
855 		inp_set_activity_bitmap(last);
856 	}
857 	so_recv_data_stat(last->inp_socket, n, 0);
858 	m_adj(n, off);
859 	if (sbappendaddr(&last->inp_socket->so_rcv, append_sa,
860 	    n, opts, NULL) == 0) {
861 		udpstat.udps_fullsock++;
862 	} else {
863 		sorwakeup(last->inp_socket);
864 	}
865 	return;
866 error:
867 	m_freem(n);
868 	m_freem(opts);
869 }
870 
871 /*
872  * Notify a udp user of an asynchronous error;
873  * just wake up so that he can collect error status.
874  */
875 void
udp_notify(struct inpcb * inp,int errno)876 udp_notify(struct inpcb *inp, int errno)
877 {
878 	inp->inp_socket->so_error = (u_short)errno;
879 	sorwakeup(inp->inp_socket);
880 	sowwakeup(inp->inp_socket);
881 }
882 
883 void
udp_ctlinput(int cmd,struct sockaddr * sa,void * vip,__unused struct ifnet * ifp)884 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip, __unused struct ifnet * ifp)
885 {
886 	struct ipctlparam *ctl_param = vip;
887 	struct ip *ip = NULL;
888 	struct mbuf *m = NULL;
889 	void (*notify)(struct inpcb *, int) = udp_notify;
890 	struct in_addr faddr;
891 	struct inpcb *inp = NULL;
892 	struct icmp *icp = NULL;
893 	size_t off;
894 
895 	if (ctl_param != NULL) {
896 		ip = ctl_param->ipc_icmp_ip;
897 		icp = ctl_param->ipc_icmp;
898 		m = ctl_param->ipc_m;
899 		off = ctl_param->ipc_off;
900 	} else {
901 		ip = NULL;
902 		icp = NULL;
903 		m = NULL;
904 		off = 0;
905 	}
906 
907 	faddr = ((struct sockaddr_in *)(void *)sa)->sin_addr;
908 	if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) {
909 		return;
910 	}
911 
912 	if (PRC_IS_REDIRECT(cmd)) {
913 		ip = 0;
914 		notify = in_rtchange;
915 	} else if (cmd == PRC_HOSTDEAD) {
916 		ip = 0;
917 	} else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) {
918 		return;
919 	}
920 	if (ip) {
921 		struct udphdr uh;
922 
923 		/* Check if we can safely get the ports from the UDP header */
924 		if (m == NULL ||
925 		    (m->m_len < off + sizeof(uh))) {
926 			/* Insufficient length */
927 			return;
928 		}
929 
930 		bcopy(m->m_data + off, &uh, sizeof(uh));
931 		inp = in_pcblookup_hash(&udbinfo, faddr, uh.uh_dport,
932 		    ip->ip_src, uh.uh_sport, 0, NULL);
933 
934 		if (inp != NULL && inp->inp_socket != NULL) {
935 			udp_lock(inp->inp_socket, 1, 0);
936 			if (in_pcb_checkstate(inp, WNT_RELEASE, 1) ==
937 			    WNT_STOPUSING) {
938 				udp_unlock(inp->inp_socket, 1, 0);
939 				return;
940 			}
941 			if (cmd == PRC_MSGSIZE && !uuid_is_null(inp->necp_client_uuid)) {
942 				uuid_t null_uuid;
943 				uuid_clear(null_uuid);
944 				necp_update_flow_protoctl_event(null_uuid, inp->necp_client_uuid,
945 				    PRC_MSGSIZE, ntohs(icp->icmp_nextmtu), 0);
946 				/*
947 				 * Avoid calling udp_notify() to set so_error
948 				 * when using Network.framework since the notification
949 				 * of PRC_MSGSIZE has been delivered through NECP.
950 				 */
951 			} else {
952 				(*notify)(inp, inetctlerrmap[cmd]);
953 			}
954 			udp_unlock(inp->inp_socket, 1, 0);
955 		}
956 #if SKYWALK
957 		else {
958 			union sockaddr_in_4_6 sock_laddr;
959 			struct protoctl_ev_val prctl_ev_val;
960 			bzero(&prctl_ev_val, sizeof(prctl_ev_val));
961 			bzero(&sock_laddr, sizeof(sock_laddr));
962 
963 			if (cmd == PRC_MSGSIZE) {
964 				prctl_ev_val.val = ntohs(icp->icmp_nextmtu);
965 			}
966 
967 			sock_laddr.sin.sin_family = AF_INET;
968 			sock_laddr.sin.sin_len = sizeof(sock_laddr.sin);
969 			sock_laddr.sin.sin_addr = ip->ip_src;
970 
971 			protoctl_event_enqueue_nwk_wq_entry(ifp,
972 			    (struct sockaddr *)&sock_laddr, sa,
973 			    uh.uh_sport, uh.uh_dport, IPPROTO_UDP,
974 			    cmd, &prctl_ev_val);
975 		}
976 #endif /* SKYWALK */
977 	} else {
978 		in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify);
979 	}
980 }
981 
982 int
udp_ctloutput(struct socket * so,struct sockopt * sopt)983 udp_ctloutput(struct socket *so, struct sockopt *sopt)
984 {
985 	int     error = 0, optval = 0;
986 	struct  inpcb *inp;
987 
988 	/* Allow <SOL_SOCKET,SO_FLUSH> at this level */
989 	if (sopt->sopt_level != IPPROTO_UDP &&
990 	    !(sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_FLUSH)) {
991 		if (SOCK_CHECK_DOM(so, PF_INET6)) {
992 			error = ip6_ctloutput(so, sopt);
993 		} else {
994 			error = ip_ctloutput(so, sopt);
995 		}
996 		return error;
997 	}
998 
999 	inp = sotoinpcb(so);
1000 
1001 	switch (sopt->sopt_dir) {
1002 	case SOPT_SET:
1003 		switch (sopt->sopt_name) {
1004 		case UDP_NOCKSUM:
1005 			/* This option is settable only for UDP over IPv4 */
1006 			if (!(inp->inp_vflag & INP_IPV4)) {
1007 				error = EINVAL;
1008 				break;
1009 			}
1010 
1011 			if ((error = sooptcopyin(sopt, &optval, sizeof(optval),
1012 			    sizeof(optval))) != 0) {
1013 				break;
1014 			}
1015 
1016 			if (optval != 0) {
1017 				inp->inp_flags |= INP_UDP_NOCKSUM;
1018 			} else {
1019 				inp->inp_flags &= ~INP_UDP_NOCKSUM;
1020 			}
1021 			break;
1022 		case UDP_KEEPALIVE_OFFLOAD:
1023 		{
1024 			struct udp_keepalive_offload ka;
1025 			/*
1026 			 * If the socket is not connected, the stack will
1027 			 * not know the destination address to put in the
1028 			 * keepalive datagram. Return an error now instead
1029 			 * of failing later.
1030 			 */
1031 			if (!(so->so_state & SS_ISCONNECTED)) {
1032 				error = EINVAL;
1033 				break;
1034 			}
1035 			if (sopt->sopt_valsize != sizeof(ka)) {
1036 				error = EINVAL;
1037 				break;
1038 			}
1039 			if ((error = sooptcopyin(sopt, &ka, sizeof(ka),
1040 			    sizeof(ka))) != 0) {
1041 				break;
1042 			}
1043 
1044 			/* application should specify the type */
1045 			if (ka.ka_type == 0) {
1046 				return EINVAL;
1047 			}
1048 
1049 			if (ka.ka_interval == 0) {
1050 				/*
1051 				 * if interval is 0, disable the offload
1052 				 * mechanism
1053 				 */
1054 				if (inp->inp_keepalive_data != NULL) {
1055 					kfree_data(inp->inp_keepalive_data,
1056 					    inp->inp_keepalive_datalen);
1057 				}
1058 				inp->inp_keepalive_data = NULL;
1059 				inp->inp_keepalive_datalen = 0;
1060 				inp->inp_keepalive_interval = 0;
1061 				inp->inp_keepalive_type = 0;
1062 				inp->inp_flags2 &= ~INP2_KEEPALIVE_OFFLOAD;
1063 			} else {
1064 				if (inp->inp_keepalive_data != NULL) {
1065 					kfree_data(inp->inp_keepalive_data,
1066 					    inp->inp_keepalive_datalen);
1067 					inp->inp_keepalive_data = NULL;
1068 				}
1069 
1070 				inp->inp_keepalive_datalen = (uint8_t)min(
1071 					ka.ka_data_len,
1072 					UDP_KEEPALIVE_OFFLOAD_DATA_SIZE);
1073 				if (inp->inp_keepalive_datalen > 0) {
1074 					inp->inp_keepalive_data = (u_int8_t *)kalloc_data(
1075 						inp->inp_keepalive_datalen, Z_WAITOK);
1076 					if (inp->inp_keepalive_data == NULL) {
1077 						inp->inp_keepalive_datalen = 0;
1078 						error = ENOMEM;
1079 						break;
1080 					}
1081 					bcopy(ka.ka_data,
1082 					    inp->inp_keepalive_data,
1083 					    inp->inp_keepalive_datalen);
1084 				} else {
1085 					inp->inp_keepalive_datalen = 0;
1086 				}
1087 				inp->inp_keepalive_interval = (uint8_t)
1088 				    min(UDP_KEEPALIVE_INTERVAL_MAX_SECONDS,
1089 				    ka.ka_interval);
1090 				inp->inp_keepalive_type = ka.ka_type;
1091 				inp->inp_flags2 |= INP2_KEEPALIVE_OFFLOAD;
1092 			}
1093 			break;
1094 		}
1095 		case SO_FLUSH:
1096 			if ((error = sooptcopyin(sopt, &optval, sizeof(optval),
1097 			    sizeof(optval))) != 0) {
1098 				break;
1099 			}
1100 
1101 			error = inp_flush(inp, optval);
1102 			break;
1103 
1104 		default:
1105 			error = ENOPROTOOPT;
1106 			break;
1107 		}
1108 		break;
1109 
1110 	case SOPT_GET:
1111 		switch (sopt->sopt_name) {
1112 		case UDP_NOCKSUM:
1113 			optval = inp->inp_flags & INP_UDP_NOCKSUM;
1114 			break;
1115 
1116 		default:
1117 			error = ENOPROTOOPT;
1118 			break;
1119 		}
1120 		if (error == 0) {
1121 			error = sooptcopyout(sopt, &optval, sizeof(optval));
1122 		}
1123 		break;
1124 	}
1125 	return error;
1126 }
1127 
1128 static int
1129 udp_pcblist SYSCTL_HANDLER_ARGS
1130 {
1131 #pragma unused(oidp, arg1, arg2)
1132 	int error, i, n, sz;
1133 	struct inpcb *inp, **inp_list;
1134 	inp_gen_t gencnt;
1135 	struct xinpgen xig;
1136 
1137 	/*
1138 	 * The process of preparing the TCB list is too time-consuming and
1139 	 * resource-intensive to repeat twice on every request.
1140 	 */
1141 	lck_rw_lock_exclusive(&udbinfo.ipi_lock);
1142 	if (req->oldptr == USER_ADDR_NULL) {
1143 		n = udbinfo.ipi_count;
1144 		req->oldidx = 2 * (sizeof(xig))
1145 		    + (n + n / 8) * sizeof(struct xinpcb);
1146 		lck_rw_done(&udbinfo.ipi_lock);
1147 		return 0;
1148 	}
1149 
1150 	if (req->newptr != USER_ADDR_NULL) {
1151 		lck_rw_done(&udbinfo.ipi_lock);
1152 		return EPERM;
1153 	}
1154 
1155 	/*
1156 	 * OK, now we're committed to doing something.
1157 	 */
1158 	gencnt = udbinfo.ipi_gencnt;
1159 	sz = n = udbinfo.ipi_count;
1160 
1161 	bzero(&xig, sizeof(xig));
1162 	xig.xig_len = sizeof(xig);
1163 	xig.xig_count = n;
1164 	xig.xig_gen = gencnt;
1165 	xig.xig_sogen = so_gencnt;
1166 	error = SYSCTL_OUT(req, &xig, sizeof(xig));
1167 	if (error) {
1168 		lck_rw_done(&udbinfo.ipi_lock);
1169 		return error;
1170 	}
1171 	/*
1172 	 * We are done if there is no pcb
1173 	 */
1174 	if (n == 0) {
1175 		lck_rw_done(&udbinfo.ipi_lock);
1176 		return 0;
1177 	}
1178 
1179 	inp_list = kalloc_type(struct inpcb *, n, Z_WAITOK);
1180 	if (inp_list == NULL) {
1181 		lck_rw_done(&udbinfo.ipi_lock);
1182 		return ENOMEM;
1183 	}
1184 
1185 	for (inp = LIST_FIRST(udbinfo.ipi_listhead), i = 0; inp && i < n;
1186 	    inp = LIST_NEXT(inp, inp_list)) {
1187 		if (inp->inp_gencnt <= gencnt &&
1188 		    inp->inp_state != INPCB_STATE_DEAD) {
1189 			inp_list[i++] = inp;
1190 		}
1191 	}
1192 	n = i;
1193 
1194 	error = 0;
1195 	for (i = 0; i < n; i++) {
1196 		struct xinpcb xi;
1197 
1198 		inp = inp_list[i];
1199 
1200 		if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) {
1201 			continue;
1202 		}
1203 		udp_lock(inp->inp_socket, 1, 0);
1204 		if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) {
1205 			udp_unlock(inp->inp_socket, 1, 0);
1206 			continue;
1207 		}
1208 		if (inp->inp_gencnt > gencnt) {
1209 			udp_unlock(inp->inp_socket, 1, 0);
1210 			continue;
1211 		}
1212 
1213 		bzero(&xi, sizeof(xi));
1214 		xi.xi_len = sizeof(xi);
1215 		/* XXX should avoid extra copy */
1216 		inpcb_to_compat(inp, &xi.xi_inp);
1217 		if (inp->inp_socket) {
1218 			sotoxsocket(inp->inp_socket, &xi.xi_socket);
1219 		}
1220 
1221 		udp_unlock(inp->inp_socket, 1, 0);
1222 
1223 		error = SYSCTL_OUT(req, &xi, sizeof(xi));
1224 	}
1225 	if (!error) {
1226 		/*
1227 		 * Give the user an updated idea of our state.
1228 		 * If the generation differs from what we told
1229 		 * her before, she knows that something happened
1230 		 * while we were processing this request, and it
1231 		 * might be necessary to retry.
1232 		 */
1233 		bzero(&xig, sizeof(xig));
1234 		xig.xig_len = sizeof(xig);
1235 		xig.xig_gen = udbinfo.ipi_gencnt;
1236 		xig.xig_sogen = so_gencnt;
1237 		xig.xig_count = udbinfo.ipi_count;
1238 		error = SYSCTL_OUT(req, &xig, sizeof(xig));
1239 	}
1240 
1241 	lck_rw_done(&udbinfo.ipi_lock);
1242 	kfree_type(struct inpcb *, sz, inp_list);
1243 	return error;
1244 }
1245 
1246 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
1247     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, udp_pcblist,
1248     "S,xinpcb", "List of active UDP sockets");
1249 
1250 #if XNU_TARGET_OS_OSX
1251 
1252 static int
1253 udp_pcblist64 SYSCTL_HANDLER_ARGS
1254 {
1255 #pragma unused(oidp, arg1, arg2)
1256 	int error, i, n, sz;
1257 	struct inpcb *inp, **inp_list;
1258 	inp_gen_t gencnt;
1259 	struct xinpgen xig;
1260 
1261 	/*
1262 	 * The process of preparing the TCB list is too time-consuming and
1263 	 * resource-intensive to repeat twice on every request.
1264 	 */
1265 	lck_rw_lock_shared(&udbinfo.ipi_lock);
1266 	if (req->oldptr == USER_ADDR_NULL) {
1267 		n = udbinfo.ipi_count;
1268 		req->oldidx =
1269 		    2 * (sizeof(xig)) + (n + n / 8) * sizeof(struct xinpcb64);
1270 		lck_rw_done(&udbinfo.ipi_lock);
1271 		return 0;
1272 	}
1273 
1274 	if (req->newptr != USER_ADDR_NULL) {
1275 		lck_rw_done(&udbinfo.ipi_lock);
1276 		return EPERM;
1277 	}
1278 
1279 	/*
1280 	 * OK, now we're committed to doing something.
1281 	 */
1282 	gencnt = udbinfo.ipi_gencnt;
1283 	sz = n = udbinfo.ipi_count;
1284 
1285 	bzero(&xig, sizeof(xig));
1286 	xig.xig_len = sizeof(xig);
1287 	xig.xig_count = n;
1288 	xig.xig_gen = gencnt;
1289 	xig.xig_sogen = so_gencnt;
1290 	error = SYSCTL_OUT(req, &xig, sizeof(xig));
1291 	if (error) {
1292 		lck_rw_done(&udbinfo.ipi_lock);
1293 		return error;
1294 	}
1295 	/*
1296 	 * We are done if there is no pcb
1297 	 */
1298 	if (n == 0) {
1299 		lck_rw_done(&udbinfo.ipi_lock);
1300 		return 0;
1301 	}
1302 
1303 	inp_list = kalloc_type(struct inpcb *, n, Z_WAITOK);
1304 	if (inp_list == NULL) {
1305 		lck_rw_done(&udbinfo.ipi_lock);
1306 		return ENOMEM;
1307 	}
1308 
1309 	for (inp = LIST_FIRST(udbinfo.ipi_listhead), i = 0; inp && i < n;
1310 	    inp = LIST_NEXT(inp, inp_list)) {
1311 		if (inp->inp_gencnt <= gencnt &&
1312 		    inp->inp_state != INPCB_STATE_DEAD) {
1313 			inp_list[i++] = inp;
1314 		}
1315 	}
1316 	n = i;
1317 
1318 	error = 0;
1319 	for (i = 0; i < n; i++) {
1320 		struct xinpcb64 xi;
1321 
1322 		inp = inp_list[i];
1323 
1324 		if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) == WNT_STOPUSING) {
1325 			continue;
1326 		}
1327 		udp_lock(inp->inp_socket, 1, 0);
1328 		if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) {
1329 			udp_unlock(inp->inp_socket, 1, 0);
1330 			continue;
1331 		}
1332 		if (inp->inp_gencnt > gencnt) {
1333 			udp_unlock(inp->inp_socket, 1, 0);
1334 			continue;
1335 		}
1336 
1337 		bzero(&xi, sizeof(xi));
1338 		xi.xi_len = sizeof(xi);
1339 		inpcb_to_xinpcb64(inp, &xi);
1340 		if (inp->inp_socket) {
1341 			sotoxsocket64(inp->inp_socket, &xi.xi_socket);
1342 		}
1343 
1344 		udp_unlock(inp->inp_socket, 1, 0);
1345 
1346 		error = SYSCTL_OUT(req, &xi, sizeof(xi));
1347 	}
1348 	if (!error) {
1349 		/*
1350 		 * Give the user an updated idea of our state.
1351 		 * If the generation differs from what we told
1352 		 * her before, she knows that something happened
1353 		 * while we were processing this request, and it
1354 		 * might be necessary to retry.
1355 		 */
1356 		bzero(&xig, sizeof(xig));
1357 		xig.xig_len = sizeof(xig);
1358 		xig.xig_gen = udbinfo.ipi_gencnt;
1359 		xig.xig_sogen = so_gencnt;
1360 		xig.xig_count = udbinfo.ipi_count;
1361 		error = SYSCTL_OUT(req, &xig, sizeof(xig));
1362 	}
1363 
1364 	lck_rw_done(&udbinfo.ipi_lock);
1365 	kfree_type(struct inpcb *, sz, inp_list);
1366 	return error;
1367 }
1368 
1369 SYSCTL_PROC(_net_inet_udp, OID_AUTO, pcblist64,
1370     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, udp_pcblist64,
1371     "S,xinpcb64", "List of active UDP sockets");
1372 
1373 #endif /* XNU_TARGET_OS_OSX */
1374 
1375 static int
1376 udp_pcblist_n SYSCTL_HANDLER_ARGS
1377 {
1378 #pragma unused(oidp, arg1, arg2)
1379 	return get_pcblist_n(IPPROTO_UDP, req, &udbinfo);
1380 }
1381 
1382 SYSCTL_PROC(_net_inet_udp, OID_AUTO, pcblist_n,
1383     CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, udp_pcblist_n,
1384     "S,xinpcb_n", "List of active UDP sockets");
1385 
1386 __private_extern__ void
udp_get_ports_used(ifnet_t ifp,int protocol,uint32_t flags,bitstr_t * bitfield)1387 udp_get_ports_used(ifnet_t ifp, int protocol, uint32_t flags,
1388     bitstr_t *bitfield)
1389 {
1390 	inpcb_get_ports_used(ifp, protocol, flags, bitfield,
1391 	    &udbinfo);
1392 }
1393 
1394 __private_extern__ uint32_t
udp_count_opportunistic(unsigned int ifindex,u_int32_t flags)1395 udp_count_opportunistic(unsigned int ifindex, u_int32_t flags)
1396 {
1397 	return inpcb_count_opportunistic(ifindex, &udbinfo, flags);
1398 }
1399 
1400 __private_extern__ uint32_t
udp_find_anypcb_byaddr(struct ifaddr * ifa)1401 udp_find_anypcb_byaddr(struct ifaddr *ifa)
1402 {
1403 #if SKYWALK
1404 	if (netns_is_enabled()) {
1405 		return netns_find_anyres_byaddr(ifa, IPPROTO_UDP);
1406 	} else
1407 #endif /* SKYWALK */
1408 	return inpcb_find_anypcb_byaddr(ifa, &udbinfo);
1409 }
1410 
1411 static int
udp_check_pktinfo(struct mbuf * control,struct ifnet ** outif,struct in_addr * laddr)1412 udp_check_pktinfo(struct mbuf *control, struct ifnet **outif,
1413     struct in_addr *laddr)
1414 {
1415 	struct cmsghdr *cm = 0;
1416 	struct in_pktinfo *pktinfo;
1417 	struct ifnet *ifp;
1418 
1419 	if (outif != NULL) {
1420 		*outif = NULL;
1421 	}
1422 
1423 	/*
1424 	 * XXX: Currently, we assume all the optional information is stored
1425 	 * in a single mbuf.
1426 	 */
1427 	if (control->m_next) {
1428 		return EINVAL;
1429 	}
1430 
1431 	if (control->m_len < CMSG_LEN(0)) {
1432 		return EINVAL;
1433 	}
1434 
1435 	for (cm = M_FIRST_CMSGHDR(control);
1436 	    is_cmsg_valid(control, cm);
1437 	    cm = M_NXT_CMSGHDR(control, cm)) {
1438 		if (cm->cmsg_level != IPPROTO_IP ||
1439 		    cm->cmsg_type != IP_PKTINFO) {
1440 			continue;
1441 		}
1442 
1443 		if (cm->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo))) {
1444 			return EINVAL;
1445 		}
1446 
1447 		pktinfo =  (struct in_pktinfo *)(void *)CMSG_DATA(cm);
1448 
1449 		/* Check for a valid ifindex in pktinfo */
1450 		ifnet_head_lock_shared();
1451 
1452 		if (pktinfo->ipi_ifindex > if_index) {
1453 			ifnet_head_done();
1454 			return ENXIO;
1455 		}
1456 
1457 		/*
1458 		 * If ipi_ifindex is specified it takes precedence
1459 		 * over ipi_spec_dst.
1460 		 */
1461 		if (pktinfo->ipi_ifindex) {
1462 			ifp = ifindex2ifnet[pktinfo->ipi_ifindex];
1463 			if (ifp == NULL) {
1464 				ifnet_head_done();
1465 				return ENXIO;
1466 			}
1467 			if (outif != NULL) {
1468 				ifnet_reference(ifp);
1469 				*outif = ifp;
1470 			}
1471 			ifnet_head_done();
1472 			laddr->s_addr = INADDR_ANY;
1473 			break;
1474 		}
1475 
1476 		ifnet_head_done();
1477 
1478 		/*
1479 		 * Use the provided ipi_spec_dst address for temp
1480 		 * source address.
1481 		 */
1482 		*laddr = pktinfo->ipi_spec_dst;
1483 		break;
1484 	}
1485 	return 0;
1486 }
1487 
1488 int
udp_output(struct inpcb * inp,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct proc * p)1489 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1490     struct mbuf *control, struct proc *p)
1491 {
1492 	struct udpiphdr *ui;
1493 	int len = m->m_pkthdr.len;
1494 	struct sockaddr_in *sin;
1495 	struct in_addr origladdr, laddr, faddr, pi_laddr;
1496 	u_short lport, fport;
1497 	int error = 0, udp_dodisconnect = 0, pktinfo = 0;
1498 	struct socket *so = inp->inp_socket;
1499 	int soopts = 0;
1500 	struct mbuf *inpopts;
1501 	struct ip_moptions *mopts;
1502 	struct route ro;
1503 	struct ip_out_args ipoa;
1504 	bool sndinprog_cnt_used = false;
1505 #if CONTENT_FILTER
1506 	struct m_tag *cfil_tag = NULL;
1507 	bool cfil_faddr_use = false;
1508 	uint32_t cfil_so_state_change_cnt = 0;
1509 	uint32_t cfil_so_options = 0;
1510 	struct sockaddr *cfil_faddr = NULL;
1511 #endif
1512 	bool check_qos_marking_again = (so->so_flags1 & SOF1_QOSMARKING_POLICY_OVERRIDE) ? FALSE : TRUE;
1513 
1514 	bzero(&ipoa, sizeof(ipoa));
1515 	ipoa.ipoa_boundif = IFSCOPE_NONE;
1516 	ipoa.ipoa_flags = IPOAF_SELECT_SRCIF;
1517 
1518 	struct ifnet *outif = NULL;
1519 	struct flowadv *adv = &ipoa.ipoa_flowadv;
1520 	int sotc = SO_TC_UNSPEC;
1521 	int netsvctype = _NET_SERVICE_TYPE_UNSPEC;
1522 	struct ifnet *origoutifp = NULL;
1523 	int flowadv = 0;
1524 	int tos = IPTOS_UNSPEC;
1525 
1526 	/* Enable flow advisory only when connected */
1527 	flowadv = (so->so_state & SS_ISCONNECTED) ? 1 : 0;
1528 	pi_laddr.s_addr = INADDR_ANY;
1529 
1530 	KERNEL_DEBUG(DBG_FNC_UDP_OUTPUT | DBG_FUNC_START, 0, 0, 0, 0, 0);
1531 
1532 	socket_lock_assert_owned(so);
1533 
1534 #if CONTENT_FILTER
1535 	/*
1536 	 * If socket is subject to UDP Content Filter and no addr is passed in,
1537 	 * retrieve CFIL saved state from mbuf and use it if necessary.
1538 	 */
1539 	if (CFIL_DGRAM_FILTERED(so) && !addr) {
1540 		cfil_tag = cfil_dgram_get_socket_state(m, &cfil_so_state_change_cnt, &cfil_so_options, &cfil_faddr, NULL);
1541 		if (cfil_tag) {
1542 			sin = (struct sockaddr_in *)(void *)cfil_faddr;
1543 			if (inp && inp->inp_faddr.s_addr == INADDR_ANY) {
1544 				/*
1545 				 * Socket is unconnected, simply use the saved faddr as 'addr' to go through
1546 				 * the connect/disconnect logic.
1547 				 */
1548 				addr = (struct sockaddr *)cfil_faddr;
1549 			} else if ((so->so_state_change_cnt != cfil_so_state_change_cnt) &&
1550 			    (inp->inp_fport != sin->sin_port ||
1551 			    inp->inp_faddr.s_addr != sin->sin_addr.s_addr)) {
1552 				/*
1553 				 * Socket is connected but socket state and dest addr/port changed.
1554 				 * We need to use the saved faddr info.
1555 				 */
1556 				cfil_faddr_use = true;
1557 			}
1558 		}
1559 	}
1560 #endif
1561 
1562 	if (control != NULL) {
1563 		tos = so_tos_from_control(control);
1564 		sotc = so_tc_from_control(control, &netsvctype);
1565 		VERIFY(outif == NULL);
1566 		error = udp_check_pktinfo(control, &outif, &pi_laddr);
1567 		m_freem(control);
1568 		control = NULL;
1569 		if (error) {
1570 			goto release;
1571 		}
1572 		pktinfo++;
1573 		if (outif != NULL) {
1574 			ipoa.ipoa_boundif = outif->if_index;
1575 		}
1576 	}
1577 	if (sotc == SO_TC_UNSPEC) {
1578 		sotc = so->so_traffic_class;
1579 		netsvctype = so->so_netsvctype;
1580 	}
1581 
1582 	KERNEL_DEBUG(DBG_LAYER_OUT_BEG, inp->inp_fport, inp->inp_lport,
1583 	    inp->inp_laddr.s_addr, inp->inp_faddr.s_addr,
1584 	    (htons((u_short)len + sizeof(struct udphdr))));
1585 
1586 	if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1587 		error = EMSGSIZE;
1588 		goto release;
1589 	}
1590 
1591 	if (flowadv && INP_WAIT_FOR_IF_FEEDBACK(inp)) {
1592 		/*
1593 		 * The socket is flow-controlled, drop the packets
1594 		 * until the inp is not flow controlled
1595 		 */
1596 		error = ENOBUFS;
1597 		goto release;
1598 	}
1599 	/*
1600 	 * If socket was bound to an ifindex, tell ip_output about it.
1601 	 * If the ancillary IP_PKTINFO option contains an interface index,
1602 	 * it takes precedence over the one specified by IP_BOUND_IF.
1603 	 */
1604 	if (ipoa.ipoa_boundif == IFSCOPE_NONE &&
1605 	    (inp->inp_flags & INP_BOUND_IF)) {
1606 		VERIFY(inp->inp_boundifp != NULL);
1607 		ifnet_reference(inp->inp_boundifp);     /* for this routine */
1608 		if (outif != NULL) {
1609 			ifnet_release(outif);
1610 		}
1611 		outif = inp->inp_boundifp;
1612 		ipoa.ipoa_boundif = outif->if_index;
1613 	}
1614 	if (INP_NO_CELLULAR(inp)) {
1615 		ipoa.ipoa_flags |=  IPOAF_NO_CELLULAR;
1616 	}
1617 	if (INP_NO_EXPENSIVE(inp)) {
1618 		ipoa.ipoa_flags |=  IPOAF_NO_EXPENSIVE;
1619 	}
1620 	if (INP_NO_CONSTRAINED(inp)) {
1621 		ipoa.ipoa_flags |=  IPOAF_NO_CONSTRAINED;
1622 	}
1623 	if (INP_AWDL_UNRESTRICTED(inp)) {
1624 		ipoa.ipoa_flags |=  IPOAF_AWDL_UNRESTRICTED;
1625 	}
1626 	ipoa.ipoa_sotc = sotc;
1627 	ipoa.ipoa_netsvctype = netsvctype;
1628 	soopts |= IP_OUTARGS;
1629 
1630 	/*
1631 	 * If there was a routing change, discard cached route and check
1632 	 * that we have a valid source address.  Reacquire a new source
1633 	 * address if INADDR_ANY was specified.
1634 	 *
1635 	 * If we are using cfil saved state, go through this cache cleanup
1636 	 * so that we can get a new route.
1637 	 */
1638 	if (ROUTE_UNUSABLE(&inp->inp_route)
1639 #if CONTENT_FILTER
1640 	    || cfil_faddr_use
1641 #endif
1642 	    ) {
1643 		struct in_ifaddr *ia = NULL;
1644 
1645 		ROUTE_RELEASE(&inp->inp_route);
1646 
1647 		/* src address is gone? */
1648 		if (inp->inp_laddr.s_addr != INADDR_ANY &&
1649 		    (ia = ifa_foraddr(inp->inp_laddr.s_addr)) == NULL) {
1650 			if (!(inp->inp_flags & INP_INADDR_ANY) ||
1651 			    (so->so_state & SS_ISCONNECTED)) {
1652 				/*
1653 				 * Rdar://5448998
1654 				 * If the source address is gone, return an
1655 				 * error if:
1656 				 * - the source was specified
1657 				 * - the socket was already connected
1658 				 */
1659 				soevent(so, (SO_FILT_HINT_LOCKED |
1660 				    SO_FILT_HINT_NOSRCADDR));
1661 				error = EADDRNOTAVAIL;
1662 				goto release;
1663 			} else {
1664 				/* new src will be set later */
1665 				inp->inp_laddr.s_addr = INADDR_ANY;
1666 				inp->inp_last_outifp = NULL;
1667 #if SKYWALK
1668 				if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
1669 					netns_set_ifnet(&inp->inp_netns_token, NULL);
1670 				}
1671 #endif /* SKYWALK */
1672 			}
1673 		}
1674 		if (ia != NULL) {
1675 			IFA_REMREF(&ia->ia_ifa);
1676 		}
1677 	}
1678 
1679 	/*
1680 	 * IP_PKTINFO option check.  If a temporary scope or src address
1681 	 * is provided, use it for this packet only and make sure we forget
1682 	 * it after sending this datagram.
1683 	 */
1684 	if (pi_laddr.s_addr != INADDR_ANY ||
1685 	    (ipoa.ipoa_boundif != IFSCOPE_NONE && pktinfo)) {
1686 		/* temp src address for this datagram only */
1687 		laddr = pi_laddr;
1688 		origladdr.s_addr = INADDR_ANY;
1689 		/* we don't want to keep the laddr or route */
1690 		udp_dodisconnect = 1;
1691 		/* remember we don't care about src addr */
1692 		inp->inp_flags |= INP_INADDR_ANY;
1693 	} else {
1694 		origladdr = laddr = inp->inp_laddr;
1695 	}
1696 
1697 	origoutifp = inp->inp_last_outifp;
1698 	faddr = inp->inp_faddr;
1699 	lport = inp->inp_lport;
1700 	fport = inp->inp_fport;
1701 
1702 #if CONTENT_FILTER
1703 	if (cfil_faddr_use) {
1704 		faddr = ((struct sockaddr_in *)(void *)cfil_faddr)->sin_addr;
1705 		fport = ((struct sockaddr_in *)(void *)cfil_faddr)->sin_port;
1706 	}
1707 #endif
1708 	inp->inp_sndinprog_cnt++;
1709 	sndinprog_cnt_used = true;
1710 
1711 	if (addr) {
1712 		sin = (struct sockaddr_in *)(void *)addr;
1713 		if (faddr.s_addr != INADDR_ANY) {
1714 			error = EISCONN;
1715 			goto release;
1716 		}
1717 		if (lport == 0) {
1718 			/*
1719 			 * In case we don't have a local port set, go through
1720 			 * the full connect.  We don't have a local port yet
1721 			 * (i.e., we can't be looked up), so it's not an issue
1722 			 * if the input runs at the same time we do this.
1723 			 */
1724 			/* if we have a source address specified, use that */
1725 			if (pi_laddr.s_addr != INADDR_ANY) {
1726 				inp->inp_laddr = pi_laddr;
1727 			}
1728 			/*
1729 			 * If a scope is specified, use it.  Scope from
1730 			 * IP_PKTINFO takes precendence over the the scope
1731 			 * set via INP_BOUND_IF.
1732 			 */
1733 			error = in_pcbconnect(inp, addr, p, ipoa.ipoa_boundif,
1734 			    &outif);
1735 			if (error) {
1736 				goto release;
1737 			}
1738 
1739 			laddr = inp->inp_laddr;
1740 			lport = inp->inp_lport;
1741 			faddr = inp->inp_faddr;
1742 			fport = inp->inp_fport;
1743 			udp_dodisconnect = 1;
1744 
1745 			/* synch up in case in_pcbladdr() overrides */
1746 			if (outif != NULL && ipoa.ipoa_boundif != IFSCOPE_NONE) {
1747 				ipoa.ipoa_boundif = outif->if_index;
1748 			}
1749 		} else {
1750 			/*
1751 			 * Fast path case
1752 			 *
1753 			 * We have a full address and a local port; use those
1754 			 * info to build the packet without changing the pcb
1755 			 * and interfering with the input path. See 3851370.
1756 			 *
1757 			 * Scope from IP_PKTINFO takes precendence over the
1758 			 * the scope set via INP_BOUND_IF.
1759 			 */
1760 			if (laddr.s_addr == INADDR_ANY) {
1761 				if ((error = in_pcbladdr(inp, addr, &laddr,
1762 				    ipoa.ipoa_boundif, &outif, 0)) != 0) {
1763 					goto release;
1764 				}
1765 				/*
1766 				 * from pcbconnect: remember we don't
1767 				 * care about src addr.
1768 				 */
1769 				inp->inp_flags |= INP_INADDR_ANY;
1770 
1771 				/* synch up in case in_pcbladdr() overrides */
1772 				if (outif != NULL &&
1773 				    ipoa.ipoa_boundif != IFSCOPE_NONE) {
1774 					ipoa.ipoa_boundif = outif->if_index;
1775 				}
1776 			}
1777 
1778 			faddr = sin->sin_addr;
1779 			fport = sin->sin_port;
1780 		}
1781 	} else {
1782 		if (faddr.s_addr == INADDR_ANY) {
1783 			error = ENOTCONN;
1784 			goto release;
1785 		}
1786 	}
1787 
1788 	if (inp->inp_flowhash == 0) {
1789 		inp_calc_flowhash(inp);
1790 		ASSERT(inp->inp_flowhash != 0);
1791 	}
1792 
1793 	if (fport == htons(53) && !(so->so_flags1 & SOF1_DNS_COUNTED)) {
1794 		so->so_flags1 |= SOF1_DNS_COUNTED;
1795 		INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet_dgram_dns);
1796 	}
1797 
1798 	/*
1799 	 * Calculate data length and get a mbuf
1800 	 * for UDP and IP headers.
1801 	 */
1802 	M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT, 1);
1803 	if (m == 0) {
1804 		error = ENOBUFS;
1805 		goto abort;
1806 	}
1807 
1808 	/*
1809 	 * Fill in mbuf with extended UDP header
1810 	 * and addresses and length put into network format.
1811 	 */
1812 	ui = mtod(m, struct udpiphdr *);
1813 	bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1814 	ui->ui_pr = IPPROTO_UDP;
1815 	ui->ui_src = laddr;
1816 	ui->ui_dst = faddr;
1817 	ui->ui_sport = lport;
1818 	ui->ui_dport = fport;
1819 	ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1820 
1821 	/*
1822 	 * Set the Don't Fragment bit in the IP header.
1823 	 */
1824 	if (inp->inp_flags2 & INP2_DONTFRAG) {
1825 		struct ip *ip;
1826 
1827 		ip = (struct ip *)&ui->ui_i;
1828 		ip->ip_off |= IP_DF;
1829 	}
1830 
1831 	/*
1832 	 * Set up checksum to pseudo header checksum and output datagram.
1833 	 *
1834 	 * Treat flows to be CLAT46'd as IPv6 flow and compute checksum
1835 	 * no matter what, as IPv6 mandates checksum for UDP.
1836 	 *
1837 	 * Here we only compute the one's complement sum of the pseudo header.
1838 	 * The payload computation and final complement is delayed to much later
1839 	 * in IP processing to decide if remaining computation needs to be done
1840 	 * through offload.
1841 	 *
1842 	 * That is communicated by setting CSUM_UDP in csum_flags.
1843 	 * The offset of checksum from the start of ULP header is communicated
1844 	 * through csum_data.
1845 	 *
1846 	 * Note since this already contains the pseudo checksum header, any
1847 	 * later operation at IP layer that modify the values used here must
1848 	 * update the checksum as well (for example NAT etc).
1849 	 */
1850 	if ((inp->inp_flags2 & INP2_CLAT46_FLOW) ||
1851 	    (udpcksum && !(inp->inp_flags & INP_UDP_NOCKSUM))) {
1852 		ui->ui_sum = in_pseudo(ui->ui_src.s_addr, ui->ui_dst.s_addr,
1853 		    htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP));
1854 		m->m_pkthdr.csum_flags = (CSUM_UDP | CSUM_ZERO_INVERT);
1855 		m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1856 	} else {
1857 		ui->ui_sum = 0;
1858 	}
1859 	((struct ip *)ui)->ip_len = (uint16_t)(sizeof(struct udpiphdr) + len);
1860 	((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1861 	if (tos != IPTOS_UNSPEC) {
1862 		((struct ip *)ui)->ip_tos = (uint8_t)(tos & IPTOS_MASK);
1863 	} else {
1864 		((struct ip *)ui)->ip_tos = inp->inp_ip_tos;    /* XXX */
1865 	}
1866 	udpstat.udps_opackets++;
1867 
1868 	KERNEL_DEBUG(DBG_LAYER_OUT_END, ui->ui_dport, ui->ui_sport,
1869 	    ui->ui_src.s_addr, ui->ui_dst.s_addr, ui->ui_ulen);
1870 
1871 #if NECP
1872 	{
1873 		necp_kernel_policy_id policy_id;
1874 		necp_kernel_policy_id skip_policy_id;
1875 		u_int32_t route_rule_id;
1876 		u_int32_t pass_flags;
1877 
1878 		/*
1879 		 * We need a route to perform NECP route rule checks
1880 		 */
1881 		if (net_qos_policy_restricted != 0 &&
1882 		    ROUTE_UNUSABLE(&inp->inp_route)) {
1883 			struct sockaddr_in to;
1884 			struct sockaddr_in from;
1885 
1886 			ROUTE_RELEASE(&inp->inp_route);
1887 
1888 			bzero(&from, sizeof(struct sockaddr_in));
1889 			from.sin_family = AF_INET;
1890 			from.sin_len = sizeof(struct sockaddr_in);
1891 			from.sin_addr = laddr;
1892 
1893 			bzero(&to, sizeof(struct sockaddr_in));
1894 			to.sin_family = AF_INET;
1895 			to.sin_len = sizeof(struct sockaddr_in);
1896 			to.sin_addr = faddr;
1897 
1898 			inp->inp_route.ro_dst.sa_family = AF_INET;
1899 			inp->inp_route.ro_dst.sa_len = sizeof(struct sockaddr_in);
1900 			((struct sockaddr_in *)(void *)&inp->inp_route.ro_dst)->sin_addr =
1901 			    faddr;
1902 
1903 			rtalloc_scoped(&inp->inp_route, ipoa.ipoa_boundif);
1904 
1905 			inp_update_necp_policy(inp, (struct sockaddr *)&from,
1906 			    (struct sockaddr *)&to, ipoa.ipoa_boundif);
1907 			inp->inp_policyresult.results.qos_marking_gencount = 0;
1908 		}
1909 
1910 		if (!necp_socket_is_allowed_to_send_recv_v4(inp, lport, fport,
1911 		    &laddr, &faddr, NULL, 0, &policy_id, &route_rule_id, &skip_policy_id, &pass_flags)) {
1912 			error = EHOSTUNREACH;
1913 			goto abort;
1914 		}
1915 
1916 		necp_mark_packet_from_socket(m, inp, policy_id, route_rule_id, skip_policy_id, pass_flags);
1917 
1918 		if (net_qos_policy_restricted != 0) {
1919 			necp_socket_update_qos_marking(inp, inp->inp_route.ro_rt, route_rule_id);
1920 		}
1921 	}
1922 #endif /* NECP */
1923 	if ((so->so_flags1 & SOF1_QOSMARKING_ALLOWED)) {
1924 		ipoa.ipoa_flags |= IPOAF_QOSMARKING_ALLOWED;
1925 	}
1926 	if (check_qos_marking_again) {
1927 		ipoa.ipoa_flags |= IPOAF_REDO_QOSMARKING_POLICY;
1928 	}
1929 	ipoa.qos_marking_gencount = inp->inp_policyresult.results.qos_marking_gencount;
1930 
1931 #if IPSEC
1932 	if (inp->inp_sp != NULL && ipsec_setsocket(m, inp->inp_socket) != 0) {
1933 		error = ENOBUFS;
1934 		goto abort;
1935 	}
1936 #endif /* IPSEC */
1937 
1938 	inpopts = inp->inp_options;
1939 #if CONTENT_FILTER
1940 	if (cfil_tag && (inp->inp_socket->so_options != cfil_so_options)) {
1941 		soopts |= (cfil_so_options & (SO_DONTROUTE | SO_BROADCAST));
1942 	} else
1943 #endif
1944 	soopts |= (inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST));
1945 
1946 	mopts = inp->inp_moptions;
1947 	if (mopts != NULL) {
1948 		IMO_LOCK(mopts);
1949 		IMO_ADDREF_LOCKED(mopts);
1950 		if (IN_MULTICAST(ntohl(ui->ui_dst.s_addr)) &&
1951 		    mopts->imo_multicast_ifp != NULL) {
1952 			/* no reference needed */
1953 			inp->inp_last_outifp = mopts->imo_multicast_ifp;
1954 #if SKYWALK
1955 			if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
1956 				netns_set_ifnet(&inp->inp_netns_token,
1957 				    inp->inp_last_outifp);
1958 			}
1959 #endif /* SKYWALK */
1960 		}
1961 		IMO_UNLOCK(mopts);
1962 	}
1963 
1964 	/* Copy the cached route and take an extra reference */
1965 	inp_route_copyout(inp, &ro);
1966 
1967 	set_packet_service_class(m, so, sotc, 0);
1968 	m->m_pkthdr.pkt_flowsrc = FLOWSRC_INPCB;
1969 	m->m_pkthdr.pkt_flowid = inp->inp_flowhash;
1970 	m->m_pkthdr.pkt_proto = IPPROTO_UDP;
1971 	m->m_pkthdr.pkt_flags |= (PKTF_FLOW_ID | PKTF_FLOW_LOCALSRC);
1972 	if (flowadv) {
1973 		m->m_pkthdr.pkt_flags |= PKTF_FLOW_ADV;
1974 	}
1975 	m->m_pkthdr.tx_udp_pid = so->last_pid;
1976 	if (so->so_flags & SOF_DELEGATED) {
1977 		m->m_pkthdr.tx_udp_e_pid = so->e_pid;
1978 	} else {
1979 		m->m_pkthdr.tx_udp_e_pid = 0;
1980 	}
1981 #if (DEBUG || DEVELOPMENT)
1982 	if (so->so_flags & SOF_MARK_WAKE_PKT) {
1983 		so->so_flags &= ~SOF_MARK_WAKE_PKT;
1984 		m->m_pkthdr.pkt_flags |= PKTF_WAKE_PKT;
1985 	}
1986 #endif /* (DEBUG || DEVELOPMENT) */
1987 
1988 	m_add_crumb(m, PKT_CRUMB_UDP_OUTPUT);
1989 
1990 	if (ipoa.ipoa_boundif != IFSCOPE_NONE) {
1991 		ipoa.ipoa_flags |= IPOAF_BOUND_IF;
1992 	}
1993 
1994 	if (laddr.s_addr != INADDR_ANY) {
1995 		ipoa.ipoa_flags |= IPOAF_BOUND_SRCADDR;
1996 	}
1997 
1998 	socket_unlock(so, 0);
1999 	error = ip_output(m, inpopts, &ro, soopts, mopts, &ipoa);
2000 	m = NULL;
2001 	socket_lock(so, 0);
2002 	if (mopts != NULL) {
2003 		IMO_REMREF(mopts);
2004 	}
2005 
2006 	if (check_qos_marking_again) {
2007 		inp->inp_policyresult.results.qos_marking_gencount = ipoa.qos_marking_gencount;
2008 
2009 		if (ipoa.ipoa_flags & IPOAF_QOSMARKING_ALLOWED) {
2010 			inp->inp_socket->so_flags1 |= SOF1_QOSMARKING_ALLOWED;
2011 		} else {
2012 			inp->inp_socket->so_flags1 &= ~SOF1_QOSMARKING_ALLOWED;
2013 		}
2014 	}
2015 
2016 	if (error == 0 && nstat_collect) {
2017 		boolean_t cell, wifi, wired;
2018 
2019 		if (ro.ro_rt != NULL) {
2020 			cell = IFNET_IS_CELLULAR(ro.ro_rt->rt_ifp);
2021 			wifi = (!cell && IFNET_IS_WIFI(ro.ro_rt->rt_ifp));
2022 			wired = (!wifi && IFNET_IS_WIRED(ro.ro_rt->rt_ifp));
2023 		} else {
2024 			cell = wifi = wired = FALSE;
2025 		}
2026 		INP_ADD_STAT(inp, cell, wifi, wired, txpackets, 1);
2027 		INP_ADD_STAT(inp, cell, wifi, wired, txbytes, len);
2028 		inp_set_activity_bitmap(inp);
2029 	}
2030 
2031 	if (flowadv && (adv->code == FADV_FLOW_CONTROLLED ||
2032 	    adv->code == FADV_SUSPENDED)) {
2033 		/*
2034 		 * return a hint to the application that
2035 		 * the packet has been dropped
2036 		 */
2037 		error = ENOBUFS;
2038 		inp_set_fc_state(inp, adv->code);
2039 	}
2040 
2041 	/* Synchronize PCB cached route */
2042 	inp_route_copyin(inp, &ro);
2043 
2044 abort:
2045 	if (udp_dodisconnect) {
2046 		/* Always discard the cached route for unconnected socket */
2047 		ROUTE_RELEASE(&inp->inp_route);
2048 		in_pcbdisconnect(inp);
2049 		inp->inp_laddr = origladdr;     /* XXX rehash? */
2050 		/* no reference needed */
2051 		inp->inp_last_outifp = origoutifp;
2052 #if SKYWALK
2053 		if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
2054 			netns_set_ifnet(&inp->inp_netns_token,
2055 			    inp->inp_last_outifp);
2056 		}
2057 #endif /* SKYWALK */
2058 	} else if (inp->inp_route.ro_rt != NULL) {
2059 		struct rtentry *rt = inp->inp_route.ro_rt;
2060 		struct ifnet *outifp;
2061 
2062 		if (rt->rt_flags & (RTF_MULTICAST | RTF_BROADCAST)) {
2063 			rt = NULL;      /* unusable */
2064 		}
2065 #if CONTENT_FILTER
2066 		/*
2067 		 * Discard temporary route for cfil case
2068 		 */
2069 		if (cfil_faddr_use) {
2070 			rt = NULL;      /* unusable */
2071 		}
2072 #endif
2073 
2074 		/*
2075 		 * Always discard if it is a multicast or broadcast route.
2076 		 */
2077 		if (rt == NULL) {
2078 			ROUTE_RELEASE(&inp->inp_route);
2079 		}
2080 
2081 		/*
2082 		 * If the destination route is unicast, update outifp with
2083 		 * that of the route interface used by IP.
2084 		 */
2085 		if (rt != NULL &&
2086 		    (outifp = rt->rt_ifp) != inp->inp_last_outifp) {
2087 			inp->inp_last_outifp = outifp; /* no reference needed */
2088 #if SKYWALK
2089 			if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
2090 				netns_set_ifnet(&inp->inp_netns_token,
2091 				    inp->inp_last_outifp);
2092 			}
2093 #endif /* SKYWALK */
2094 
2095 			so->so_pktheadroom = (uint16_t)P2ROUNDUP(
2096 				sizeof(struct udphdr) +
2097 				sizeof(struct ip) +
2098 				ifnet_hdrlen(outifp) +
2099 				ifnet_mbuf_packetpreamblelen(outifp),
2100 				sizeof(u_int32_t));
2101 		}
2102 	} else {
2103 		ROUTE_RELEASE(&inp->inp_route);
2104 	}
2105 
2106 	/*
2107 	 * If output interface was cellular/expensive, and this socket is
2108 	 * denied access to it, generate an event.
2109 	 */
2110 	if (error != 0 && (ipoa.ipoa_flags & IPOAF_R_IFDENIED) &&
2111 	    (INP_NO_CELLULAR(inp) || INP_NO_EXPENSIVE(inp) || INP_NO_CONSTRAINED(inp))) {
2112 		soevent(so, (SO_FILT_HINT_LOCKED | SO_FILT_HINT_IFDENIED));
2113 	}
2114 
2115 release:
2116 	KERNEL_DEBUG(DBG_FNC_UDP_OUTPUT | DBG_FUNC_END, error, 0, 0, 0, 0);
2117 
2118 	if (m != NULL) {
2119 		m_freem(m);
2120 	}
2121 
2122 	if (outif != NULL) {
2123 		ifnet_release(outif);
2124 	}
2125 
2126 #if CONTENT_FILTER
2127 	if (cfil_tag) {
2128 		m_tag_free(cfil_tag);
2129 	}
2130 #endif
2131 	if (sndinprog_cnt_used) {
2132 		VERIFY(inp->inp_sndinprog_cnt > 0);
2133 		if (--inp->inp_sndinprog_cnt == 0) {
2134 			inp->inp_flags &= ~(INP_FC_FEEDBACK);
2135 			if (inp->inp_sndingprog_waiters > 0) {
2136 				wakeup(&inp->inp_sndinprog_cnt);
2137 			}
2138 		}
2139 		sndinprog_cnt_used = false;
2140 	}
2141 
2142 	return error;
2143 }
2144 
2145 u_int32_t       udp_sendspace = 9216;           /* really max datagram size */
2146 /* 187 1K datagrams (approx 192 KB) */
2147 u_int32_t       udp_recvspace = 187 * (1024 + sizeof(struct sockaddr_in6));
2148 
2149 /* Check that the values of udp send and recv space do not exceed sb_max */
2150 static int
sysctl_udp_sospace(struct sysctl_oid * oidp,void * arg1,int arg2,struct sysctl_req * req)2151 sysctl_udp_sospace(struct sysctl_oid *oidp, void *arg1, int arg2,
2152     struct sysctl_req *req)
2153 {
2154 #pragma unused(arg1, arg2)
2155 	u_int32_t new_value = 0, *space_p = NULL;
2156 	int changed = 0, error = 0;
2157 	u_quad_t sb_effective_max = (sb_max / (MSIZE + MCLBYTES)) * MCLBYTES;
2158 
2159 	switch (oidp->oid_number) {
2160 	case UDPCTL_RECVSPACE:
2161 		space_p = &udp_recvspace;
2162 		break;
2163 	case UDPCTL_MAXDGRAM:
2164 		space_p = &udp_sendspace;
2165 		break;
2166 	default:
2167 		return EINVAL;
2168 	}
2169 	error = sysctl_io_number(req, *space_p, sizeof(u_int32_t),
2170 	    &new_value, &changed);
2171 	if (changed) {
2172 		if (new_value > 0 && new_value <= sb_effective_max) {
2173 			*space_p = new_value;
2174 		} else {
2175 			error = ERANGE;
2176 		}
2177 	}
2178 	return error;
2179 }
2180 
2181 SYSCTL_PROC(_net_inet_udp, UDPCTL_RECVSPACE, recvspace,
2182     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &udp_recvspace, 0,
2183     &sysctl_udp_sospace, "IU", "Maximum incoming UDP datagram size");
2184 
2185 SYSCTL_PROC(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram,
2186     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &udp_sendspace, 0,
2187     &sysctl_udp_sospace, "IU", "Maximum outgoing UDP datagram size");
2188 
2189 int
udp_abort(struct socket * so)2190 udp_abort(struct socket *so)
2191 {
2192 	struct inpcb *inp;
2193 
2194 	inp = sotoinpcb(so);
2195 	if (inp == NULL) {
2196 		panic("%s: so=%p null inp", __func__, so);
2197 		/* NOTREACHED */
2198 	}
2199 	soisdisconnected(so);
2200 	in_pcbdetach(inp);
2201 	return 0;
2202 }
2203 
2204 int
udp_attach(struct socket * so,int proto,struct proc * p)2205 udp_attach(struct socket *so, int proto, struct proc *p)
2206 {
2207 #pragma unused(proto)
2208 	struct inpcb *inp;
2209 	int error;
2210 
2211 	error = soreserve(so, udp_sendspace, udp_recvspace);
2212 	if (error != 0) {
2213 		return error;
2214 	}
2215 	inp = sotoinpcb(so);
2216 	if (inp != NULL) {
2217 		panic("%s so=%p inp=%p", __func__, so, inp);
2218 		/* NOTREACHED */
2219 	}
2220 	error = in_pcballoc(so, &udbinfo, p);
2221 	if (error != 0) {
2222 		return error;
2223 	}
2224 	inp = (struct inpcb *)so->so_pcb;
2225 	inp->inp_vflag |= INP_IPV4;
2226 	inp->inp_ip_ttl = (uint8_t)ip_defttl;
2227 	if (nstat_collect) {
2228 		nstat_udp_new_pcb(inp);
2229 	}
2230 	return 0;
2231 }
2232 
2233 int
udp_bind(struct socket * so,struct sockaddr * nam,struct proc * p)2234 udp_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
2235 {
2236 	struct inpcb *inp;
2237 	int error;
2238 
2239 	if (nam->sa_family != 0 && nam->sa_family != AF_INET &&
2240 	    nam->sa_family != AF_INET6) {
2241 		return EAFNOSUPPORT;
2242 	}
2243 
2244 	inp = sotoinpcb(so);
2245 	if (inp == NULL) {
2246 		return EINVAL;
2247 	}
2248 	error = in_pcbbind(inp, nam, p);
2249 
2250 #if NECP
2251 	/* Update NECP client with bind result if not in middle of connect */
2252 	if (error == 0 &&
2253 	    (inp->inp_flags2 & INP2_CONNECT_IN_PROGRESS) &&
2254 	    !uuid_is_null(inp->necp_client_uuid)) {
2255 		socket_unlock(so, 0);
2256 		necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
2257 		socket_lock(so, 0);
2258 	}
2259 #endif /* NECP */
2260 
2261 	return error;
2262 }
2263 
2264 int
udp_connect(struct socket * so,struct sockaddr * nam,struct proc * p)2265 udp_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
2266 {
2267 	struct inpcb *inp;
2268 	int error;
2269 
2270 	inp = sotoinpcb(so);
2271 	if (inp == NULL) {
2272 		return EINVAL;
2273 	}
2274 	if (inp->inp_faddr.s_addr != INADDR_ANY) {
2275 		return EISCONN;
2276 	}
2277 
2278 	if (!(so->so_flags1 & SOF1_CONNECT_COUNTED)) {
2279 		so->so_flags1 |= SOF1_CONNECT_COUNTED;
2280 		INC_ATOMIC_INT64_LIM(net_api_stats.nas_socket_inet_dgram_connected);
2281 	}
2282 
2283 #if NECP
2284 #if FLOW_DIVERT
2285 	if (necp_socket_should_use_flow_divert(inp)) {
2286 		error = flow_divert_pcb_init(so);
2287 		if (error == 0) {
2288 			error = flow_divert_connect_out(so, nam, p);
2289 		}
2290 		return error;
2291 	}
2292 #endif /* FLOW_DIVERT */
2293 #endif /* NECP */
2294 
2295 	error = in_pcbconnect(inp, nam, p, IFSCOPE_NONE, NULL);
2296 	if (error == 0) {
2297 #if NECP
2298 		/* Update NECP client with connected five-tuple */
2299 		if (!uuid_is_null(inp->necp_client_uuid)) {
2300 			socket_unlock(so, 0);
2301 			necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
2302 			socket_lock(so, 0);
2303 		}
2304 #endif /* NECP */
2305 
2306 		soisconnected(so);
2307 		if (inp->inp_flowhash == 0) {
2308 			inp_calc_flowhash(inp);
2309 			ASSERT(inp->inp_flowhash != 0);
2310 		}
2311 	}
2312 	return error;
2313 }
2314 
2315 int
udp_connectx_common(struct socket * so,int af,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)2316 udp_connectx_common(struct socket *so, int af, struct sockaddr *src, struct sockaddr *dst,
2317     struct proc *p, uint32_t ifscope, sae_associd_t aid, sae_connid_t *pcid,
2318     uint32_t flags, void *arg, uint32_t arglen,
2319     struct uio *uio, user_ssize_t *bytes_written)
2320 {
2321 #pragma unused(aid, flags, arg, arglen)
2322 	struct inpcb *inp = sotoinpcb(so);
2323 	int error = 0;
2324 	user_ssize_t datalen = 0;
2325 
2326 	if (inp == NULL) {
2327 		return EINVAL;
2328 	}
2329 
2330 	VERIFY(dst != NULL);
2331 
2332 	ASSERT(!(inp->inp_flags2 & INP2_CONNECT_IN_PROGRESS));
2333 	inp->inp_flags2 |= INP2_CONNECT_IN_PROGRESS;
2334 
2335 #if NECP
2336 	inp_update_necp_policy(inp, src, dst, ifscope);
2337 #endif /* NECP */
2338 
2339 	/* bind socket to the specified interface, if requested */
2340 	if (ifscope != IFSCOPE_NONE &&
2341 	    (error = inp_bindif(inp, ifscope, NULL)) != 0) {
2342 		goto done;
2343 	}
2344 
2345 	/* if source address and/or port is specified, bind to it */
2346 	if (src != NULL) {
2347 		error = sobindlock(so, src, 0); /* already locked */
2348 		if (error != 0) {
2349 			goto done;
2350 		}
2351 	}
2352 
2353 	switch (af) {
2354 	case AF_INET:
2355 		error = udp_connect(so, dst, p);
2356 		break;
2357 	case AF_INET6:
2358 		error = udp6_connect(so, dst, p);
2359 		break;
2360 	default:
2361 		VERIFY(0);
2362 		/* NOTREACHED */
2363 	}
2364 
2365 	if (error != 0) {
2366 		goto done;
2367 	}
2368 
2369 	/*
2370 	 * If there is data, copy it. DATA_IDEMPOTENT is ignored.
2371 	 * CONNECT_RESUME_ON_READ_WRITE is ignored.
2372 	 */
2373 	if (uio != NULL) {
2374 		socket_unlock(so, 0);
2375 
2376 		VERIFY(bytes_written != NULL);
2377 
2378 		datalen = uio_resid(uio);
2379 		error = so->so_proto->pr_usrreqs->pru_sosend(so, NULL,
2380 		    (uio_t)uio, NULL, NULL, 0);
2381 		socket_lock(so, 0);
2382 
2383 		/* If error returned is EMSGSIZE, for example, disconnect */
2384 		if (error == 0 || error == EWOULDBLOCK) {
2385 			*bytes_written = datalen - uio_resid(uio);
2386 		} else {
2387 			(void) so->so_proto->pr_usrreqs->pru_disconnectx(so,
2388 			    SAE_ASSOCID_ANY, SAE_CONNID_ANY);
2389 		}
2390 		/*
2391 		 * mask the EWOULDBLOCK error so that the caller
2392 		 * knows that atleast the connect was successful.
2393 		 */
2394 		if (error == EWOULDBLOCK) {
2395 			error = 0;
2396 		}
2397 	}
2398 
2399 	if (error == 0 && pcid != NULL) {
2400 		*pcid = 1;      /* there is only 1 connection for UDP */
2401 	}
2402 done:
2403 	inp->inp_flags2 &= ~INP2_CONNECT_IN_PROGRESS;
2404 	return error;
2405 }
2406 
2407 int
udp_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)2408 udp_connectx(struct socket *so, struct sockaddr *src,
2409     struct sockaddr *dst, struct proc *p, uint32_t ifscope,
2410     sae_associd_t aid, sae_connid_t *pcid, uint32_t flags, void *arg,
2411     uint32_t arglen, struct uio *uio, user_ssize_t *bytes_written)
2412 {
2413 	return udp_connectx_common(so, AF_INET, src, dst,
2414 	           p, ifscope, aid, pcid, flags, arg, arglen, uio, bytes_written);
2415 }
2416 
2417 int
udp_detach(struct socket * so)2418 udp_detach(struct socket *so)
2419 {
2420 	struct inpcb *inp;
2421 
2422 	inp = sotoinpcb(so);
2423 	if (inp == NULL) {
2424 		panic("%s: so=%p null inp", __func__, so);
2425 		/* NOTREACHED */
2426 	}
2427 
2428 	/*
2429 	 * If this is a socket that does not want to wakeup the device
2430 	 * for it's traffic, the application might be waiting for
2431 	 * close to complete before going to sleep. Send a notification
2432 	 * for this kind of sockets
2433 	 */
2434 	if (so->so_options & SO_NOWAKEFROMSLEEP) {
2435 		socket_post_kev_msg_closed(so);
2436 	}
2437 
2438 	in_pcbdetach(inp);
2439 	inp->inp_state = INPCB_STATE_DEAD;
2440 	return 0;
2441 }
2442 
2443 int
udp_disconnect(struct socket * so)2444 udp_disconnect(struct socket *so)
2445 {
2446 	struct inpcb *inp;
2447 
2448 	inp = sotoinpcb(so);
2449 	if (inp == NULL) {
2450 		return EINVAL;
2451 	}
2452 	if (inp->inp_faddr.s_addr == INADDR_ANY) {
2453 		return ENOTCONN;
2454 	}
2455 
2456 	in_pcbdisconnect(inp);
2457 
2458 	/* reset flow controlled state, just in case */
2459 	inp_reset_fc_state(inp);
2460 
2461 	inp->inp_laddr.s_addr = INADDR_ANY;
2462 	so->so_state &= ~SS_ISCONNECTED;                /* XXX */
2463 	inp->inp_last_outifp = NULL;
2464 #if SKYWALK
2465 	if (NETNS_TOKEN_VALID(&inp->inp_netns_token)) {
2466 		netns_set_ifnet(&inp->inp_netns_token, NULL);
2467 	}
2468 #endif /* SKYWALK */
2469 
2470 	return 0;
2471 }
2472 
2473 int
udp_disconnectx(struct socket * so,sae_associd_t aid,sae_connid_t cid)2474 udp_disconnectx(struct socket *so, sae_associd_t aid, sae_connid_t cid)
2475 {
2476 #pragma unused(cid)
2477 	if (aid != SAE_ASSOCID_ANY && aid != SAE_ASSOCID_ALL) {
2478 		return EINVAL;
2479 	}
2480 
2481 	return udp_disconnect(so);
2482 }
2483 
2484 int
udp_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct proc * p)2485 udp_send(struct socket *so, int flags, struct mbuf *m,
2486     struct sockaddr *addr, struct mbuf *control, struct proc *p)
2487 {
2488 #ifndef FLOW_DIVERT
2489 #pragma unused(flags)
2490 #endif /* !(FLOW_DIVERT) */
2491 	struct inpcb *inp;
2492 	int error;
2493 
2494 	inp = sotoinpcb(so);
2495 	if (inp == NULL) {
2496 		if (m != NULL) {
2497 			m_freem(m);
2498 		}
2499 		if (control != NULL) {
2500 			m_freem(control);
2501 		}
2502 		return EINVAL;
2503 	}
2504 
2505 #if NECP
2506 #if FLOW_DIVERT
2507 	if (necp_socket_should_use_flow_divert(inp)) {
2508 		/* Implicit connect */
2509 		return flow_divert_implicit_data_out(so, flags, m, addr,
2510 		           control, p);
2511 	}
2512 #endif /* FLOW_DIVERT */
2513 #endif /* NECP */
2514 
2515 #if SKYWALK
2516 	sk_protect_t protect = sk_async_transmit_protect();
2517 #endif /* SKYWALK */
2518 	error = udp_output(inp, m, addr, control, p);
2519 #if SKYWALK
2520 	sk_async_transmit_unprotect(protect);
2521 #endif /* SKYWALK */
2522 
2523 	return error;
2524 }
2525 
2526 int
udp_shutdown(struct socket * so)2527 udp_shutdown(struct socket *so)
2528 {
2529 	struct inpcb *inp;
2530 
2531 	inp = sotoinpcb(so);
2532 	if (inp == NULL) {
2533 		return EINVAL;
2534 	}
2535 	socantsendmore(so);
2536 	return 0;
2537 }
2538 
2539 int
udp_lock(struct socket * so,int refcount,void * debug)2540 udp_lock(struct socket *so, int refcount, void *debug)
2541 {
2542 	void *lr_saved;
2543 
2544 	if (debug == NULL) {
2545 		lr_saved = __builtin_return_address(0);
2546 	} else {
2547 		lr_saved = debug;
2548 	}
2549 
2550 	if (so->so_pcb != NULL) {
2551 		LCK_MTX_ASSERT(&((struct inpcb *)so->so_pcb)->inpcb_mtx,
2552 		    LCK_MTX_ASSERT_NOTOWNED);
2553 		lck_mtx_lock(&((struct inpcb *)so->so_pcb)->inpcb_mtx);
2554 	} else {
2555 		panic("%s: so=%p NO PCB! lr=%p lrh= %s", __func__,
2556 		    so, lr_saved, solockhistory_nr(so));
2557 		/* NOTREACHED */
2558 	}
2559 	if (refcount) {
2560 		so->so_usecount++;
2561 	}
2562 
2563 	so->lock_lr[so->next_lock_lr] = lr_saved;
2564 	so->next_lock_lr = (so->next_lock_lr + 1) % SO_LCKDBG_MAX;
2565 	return 0;
2566 }
2567 
2568 int
udp_unlock(struct socket * so,int refcount,void * debug)2569 udp_unlock(struct socket *so, int refcount, void *debug)
2570 {
2571 	void *lr_saved;
2572 
2573 	if (debug == NULL) {
2574 		lr_saved = __builtin_return_address(0);
2575 	} else {
2576 		lr_saved = debug;
2577 	}
2578 
2579 	if (refcount) {
2580 		VERIFY(so->so_usecount > 0);
2581 		so->so_usecount--;
2582 	}
2583 	if (so->so_pcb == NULL) {
2584 		panic("%s: so=%p NO PCB! lr=%p lrh= %s", __func__,
2585 		    so, lr_saved, solockhistory_nr(so));
2586 		/* NOTREACHED */
2587 	} else {
2588 		LCK_MTX_ASSERT(&((struct inpcb *)so->so_pcb)->inpcb_mtx,
2589 		    LCK_MTX_ASSERT_OWNED);
2590 		so->unlock_lr[so->next_unlock_lr] = lr_saved;
2591 		so->next_unlock_lr = (so->next_unlock_lr + 1) % SO_LCKDBG_MAX;
2592 		lck_mtx_unlock(&((struct inpcb *)so->so_pcb)->inpcb_mtx);
2593 	}
2594 	return 0;
2595 }
2596 
2597 lck_mtx_t *
udp_getlock(struct socket * so,int flags)2598 udp_getlock(struct socket *so, int flags)
2599 {
2600 #pragma unused(flags)
2601 	struct inpcb *inp = sotoinpcb(so);
2602 
2603 	if (so->so_pcb == NULL) {
2604 		panic("%s: so=%p NULL so_pcb lrh= %s", __func__,
2605 		    so, solockhistory_nr(so));
2606 		/* NOTREACHED */
2607 	}
2608 	return &inp->inpcb_mtx;
2609 }
2610 
2611 /*
2612  * UDP garbage collector callback (inpcb_timer_func_t).
2613  *
2614  * Returns > 0 to keep timer active.
2615  */
2616 static void
udp_gc(struct inpcbinfo * ipi)2617 udp_gc(struct inpcbinfo *ipi)
2618 {
2619 	struct inpcb *inp, *inpnxt;
2620 	struct socket *so;
2621 
2622 	if (lck_rw_try_lock_exclusive(&ipi->ipi_lock) == FALSE) {
2623 		if (udp_gc_done == TRUE) {
2624 			udp_gc_done = FALSE;
2625 			/* couldn't get the lock, must lock next time */
2626 			atomic_add_32(&ipi->ipi_gc_req.intimer_fast, 1);
2627 			return;
2628 		}
2629 		lck_rw_lock_exclusive(&ipi->ipi_lock);
2630 	}
2631 
2632 	udp_gc_done = TRUE;
2633 
2634 	for (inp = udb.lh_first; inp != NULL; inp = inpnxt) {
2635 		inpnxt = inp->inp_list.le_next;
2636 
2637 		/*
2638 		 * Skip unless it's STOPUSING; garbage collector will
2639 		 * be triggered by in_pcb_checkstate() upon setting
2640 		 * wantcnt to that value.  If the PCB is already dead,
2641 		 * keep gc active to anticipate wantcnt changing.
2642 		 */
2643 		if (inp->inp_wantcnt != WNT_STOPUSING) {
2644 			continue;
2645 		}
2646 
2647 		/*
2648 		 * Skip if busy, no hurry for cleanup.  Keep gc active
2649 		 * and try the lock again during next round.
2650 		 */
2651 		if (!socket_try_lock(inp->inp_socket)) {
2652 			atomic_add_32(&ipi->ipi_gc_req.intimer_fast, 1);
2653 			continue;
2654 		}
2655 
2656 		/*
2657 		 * Keep gc active unless usecount is 0.
2658 		 */
2659 		so = inp->inp_socket;
2660 		if (so->so_usecount == 0) {
2661 			if (inp->inp_state != INPCB_STATE_DEAD) {
2662 				if (SOCK_CHECK_DOM(so, PF_INET6)) {
2663 					in6_pcbdetach(inp);
2664 				} else {
2665 					in_pcbdetach(inp);
2666 				}
2667 			}
2668 			in_pcbdispose(inp);
2669 		} else {
2670 			socket_unlock(so, 0);
2671 			atomic_add_32(&ipi->ipi_gc_req.intimer_fast, 1);
2672 		}
2673 	}
2674 	lck_rw_done(&ipi->ipi_lock);
2675 }
2676 
2677 static int
2678 udp_getstat SYSCTL_HANDLER_ARGS
2679 {
2680 #pragma unused(oidp, arg1, arg2)
2681 	if (req->oldptr == USER_ADDR_NULL) {
2682 		req->oldlen = (size_t)sizeof(struct udpstat);
2683 	}
2684 
2685 	return SYSCTL_OUT(req, &udpstat, MIN(sizeof(udpstat), req->oldlen));
2686 }
2687 
2688 void
udp_in_cksum_stats(u_int32_t len)2689 udp_in_cksum_stats(u_int32_t len)
2690 {
2691 	udpstat.udps_rcv_swcsum++;
2692 	udpstat.udps_rcv_swcsum_bytes += len;
2693 }
2694 
2695 void
udp_out_cksum_stats(u_int32_t len)2696 udp_out_cksum_stats(u_int32_t len)
2697 {
2698 	udpstat.udps_snd_swcsum++;
2699 	udpstat.udps_snd_swcsum_bytes += len;
2700 }
2701 
2702 void
udp_in6_cksum_stats(u_int32_t len)2703 udp_in6_cksum_stats(u_int32_t len)
2704 {
2705 	udpstat.udps_rcv6_swcsum++;
2706 	udpstat.udps_rcv6_swcsum_bytes += len;
2707 }
2708 
2709 void
udp_out6_cksum_stats(u_int32_t len)2710 udp_out6_cksum_stats(u_int32_t len)
2711 {
2712 	udpstat.udps_snd6_swcsum++;
2713 	udpstat.udps_snd6_swcsum_bytes += len;
2714 }
2715 
2716 /*
2717  * Checksum extended UDP header and data.
2718  */
2719 static int
udp_input_checksum(struct mbuf * m,struct udphdr * uh,int off,int ulen)2720 udp_input_checksum(struct mbuf *m, struct udphdr *uh, int off, int ulen)
2721 {
2722 	struct ifnet *ifp = m->m_pkthdr.rcvif;
2723 	struct ip *ip = mtod(m, struct ip *);
2724 	struct ipovly *ipov = (struct ipovly *)ip;
2725 
2726 	if (uh->uh_sum == 0) {
2727 		udpstat.udps_nosum++;
2728 		return 0;
2729 	}
2730 
2731 	/* ip_stripoptions() must have been called before we get here */
2732 	ASSERT((ip->ip_hl << 2) == sizeof(*ip));
2733 
2734 	if ((hwcksum_rx || (ifp->if_flags & IFF_LOOPBACK) ||
2735 	    (m->m_pkthdr.pkt_flags & PKTF_LOOP)) &&
2736 	    (m->m_pkthdr.csum_flags & CSUM_DATA_VALID)) {
2737 		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
2738 			uh->uh_sum = m->m_pkthdr.csum_rx_val;
2739 		} else {
2740 			uint32_t sum = m->m_pkthdr.csum_rx_val;
2741 			uint32_t start = m->m_pkthdr.csum_rx_start;
2742 			int32_t trailer = (m_pktlen(m) - (off + ulen));
2743 
2744 			/*
2745 			 * Perform 1's complement adjustment of octets
2746 			 * that got included/excluded in the hardware-
2747 			 * calculated checksum value.  Ignore cases
2748 			 * where the value already includes the entire
2749 			 * IP header span, as the sum for those octets
2750 			 * would already be 0 by the time we get here;
2751 			 * IP has already performed its header checksum
2752 			 * checks.  If we do need to adjust, restore
2753 			 * the original fields in the IP header when
2754 			 * computing the adjustment value.  Also take
2755 			 * care of any trailing bytes and subtract out
2756 			 * their partial sum.
2757 			 */
2758 			ASSERT(trailer >= 0);
2759 			if ((m->m_pkthdr.csum_flags & CSUM_PARTIAL) &&
2760 			    ((start != 0 && start != off) || trailer != 0)) {
2761 				uint32_t swbytes = (uint32_t)trailer;
2762 
2763 				if (start < off) {
2764 					ip->ip_len += sizeof(*ip);
2765 #if BYTE_ORDER != BIG_ENDIAN
2766 					HTONS(ip->ip_len);
2767 					HTONS(ip->ip_off);
2768 #endif /* BYTE_ORDER != BIG_ENDIAN */
2769 				}
2770 				/* callee folds in sum */
2771 				sum = m_adj_sum16(m, start, off, ulen, sum);
2772 				if (off > start) {
2773 					swbytes += (off - start);
2774 				} else {
2775 					swbytes += (start - off);
2776 				}
2777 
2778 				if (start < off) {
2779 #if BYTE_ORDER != BIG_ENDIAN
2780 					NTOHS(ip->ip_off);
2781 					NTOHS(ip->ip_len);
2782 #endif /* BYTE_ORDER != BIG_ENDIAN */
2783 					ip->ip_len -= sizeof(*ip);
2784 				}
2785 
2786 				if (swbytes != 0) {
2787 					udp_in_cksum_stats(swbytes);
2788 				}
2789 				if (trailer != 0) {
2790 					m_adj(m, -trailer);
2791 				}
2792 			}
2793 
2794 			/* callee folds in sum */
2795 			uh->uh_sum = in_pseudo(ip->ip_src.s_addr,
2796 			    ip->ip_dst.s_addr, sum + htonl(ulen + IPPROTO_UDP));
2797 		}
2798 		uh->uh_sum ^= 0xffff;
2799 	} else {
2800 		uint16_t ip_sum;
2801 		char b[9];
2802 
2803 		bcopy(ipov->ih_x1, b, sizeof(ipov->ih_x1));
2804 		bzero(ipov->ih_x1, sizeof(ipov->ih_x1));
2805 		ip_sum = ipov->ih_len;
2806 		ipov->ih_len = uh->uh_ulen;
2807 		uh->uh_sum = in_cksum(m, ulen + sizeof(struct ip));
2808 		bcopy(b, ipov->ih_x1, sizeof(ipov->ih_x1));
2809 		ipov->ih_len = ip_sum;
2810 
2811 		udp_in_cksum_stats(ulen);
2812 	}
2813 
2814 	if (uh->uh_sum != 0) {
2815 		udpstat.udps_badsum++;
2816 		IF_UDP_STATINC(ifp, badchksum);
2817 		return -1;
2818 	}
2819 
2820 	return 0;
2821 }
2822 
2823 void
udp_fill_keepalive_offload_frames(ifnet_t ifp,struct ifnet_keepalive_offload_frame * frames_array,u_int32_t frames_array_count,size_t frame_data_offset,u_int32_t * used_frames_count)2824 udp_fill_keepalive_offload_frames(ifnet_t ifp,
2825     struct ifnet_keepalive_offload_frame *frames_array,
2826     u_int32_t frames_array_count, size_t frame_data_offset,
2827     u_int32_t *used_frames_count)
2828 {
2829 	struct inpcb *inp;
2830 	inp_gen_t gencnt;
2831 	u_int32_t frame_index = *used_frames_count;
2832 
2833 	if (ifp == NULL || frames_array == NULL ||
2834 	    frames_array_count == 0 ||
2835 	    frame_index >= frames_array_count ||
2836 	    frame_data_offset >= IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) {
2837 		return;
2838 	}
2839 
2840 	lck_rw_lock_shared(&udbinfo.ipi_lock);
2841 	gencnt = udbinfo.ipi_gencnt;
2842 	LIST_FOREACH(inp, udbinfo.ipi_listhead, inp_list) {
2843 		struct socket *so;
2844 		u_int8_t *data;
2845 		struct ifnet_keepalive_offload_frame *frame;
2846 		struct mbuf *m = NULL;
2847 
2848 		if (frame_index >= frames_array_count) {
2849 			break;
2850 		}
2851 
2852 		if (inp->inp_gencnt > gencnt ||
2853 		    inp->inp_state == INPCB_STATE_DEAD) {
2854 			continue;
2855 		}
2856 
2857 		if ((so = inp->inp_socket) == NULL ||
2858 		    (so->so_state & SS_DEFUNCT)) {
2859 			continue;
2860 		}
2861 		/*
2862 		 * check for keepalive offload flag without socket
2863 		 * lock to avoid a deadlock
2864 		 */
2865 		if (!(inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD)) {
2866 			continue;
2867 		}
2868 
2869 		udp_lock(so, 1, 0);
2870 		if (!(inp->inp_vflag & (INP_IPV4 | INP_IPV6))) {
2871 			udp_unlock(so, 1, 0);
2872 			continue;
2873 		}
2874 		if ((inp->inp_vflag & INP_IPV4) &&
2875 		    (inp->inp_laddr.s_addr == INADDR_ANY ||
2876 		    inp->inp_faddr.s_addr == INADDR_ANY)) {
2877 			udp_unlock(so, 1, 0);
2878 			continue;
2879 		}
2880 		if ((inp->inp_vflag & INP_IPV6) &&
2881 		    (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) ||
2882 		    IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))) {
2883 			udp_unlock(so, 1, 0);
2884 			continue;
2885 		}
2886 		if (inp->inp_lport == 0 || inp->inp_fport == 0) {
2887 			udp_unlock(so, 1, 0);
2888 			continue;
2889 		}
2890 		if (inp->inp_last_outifp == NULL ||
2891 		    inp->inp_last_outifp->if_index != ifp->if_index) {
2892 			udp_unlock(so, 1, 0);
2893 			continue;
2894 		}
2895 		if ((inp->inp_vflag & INP_IPV4)) {
2896 			if ((frame_data_offset + sizeof(struct udpiphdr) +
2897 			    inp->inp_keepalive_datalen) >
2898 			    IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) {
2899 				udp_unlock(so, 1, 0);
2900 				continue;
2901 			}
2902 			if ((sizeof(struct udpiphdr) +
2903 			    inp->inp_keepalive_datalen) > _MHLEN) {
2904 				udp_unlock(so, 1, 0);
2905 				continue;
2906 			}
2907 		} else {
2908 			if ((frame_data_offset + sizeof(struct ip6_hdr) +
2909 			    sizeof(struct udphdr) +
2910 			    inp->inp_keepalive_datalen) >
2911 			    IFNET_KEEPALIVE_OFFLOAD_FRAME_DATA_SIZE) {
2912 				udp_unlock(so, 1, 0);
2913 				continue;
2914 			}
2915 			if ((sizeof(struct ip6_hdr) + sizeof(struct udphdr) +
2916 			    inp->inp_keepalive_datalen) > _MHLEN) {
2917 				udp_unlock(so, 1, 0);
2918 				continue;
2919 			}
2920 		}
2921 		MGETHDR(m, M_WAIT, MT_HEADER);
2922 		if (m == NULL) {
2923 			udp_unlock(so, 1, 0);
2924 			continue;
2925 		}
2926 		/*
2927 		 * This inp has all the information that is needed to
2928 		 * generate an offload frame.
2929 		 */
2930 		if (inp->inp_vflag & INP_IPV4) {
2931 			struct ip *ip;
2932 			struct udphdr *udp;
2933 
2934 			frame = &frames_array[frame_index];
2935 			frame->length = (uint8_t)(frame_data_offset +
2936 			    sizeof(struct udpiphdr) +
2937 			    inp->inp_keepalive_datalen);
2938 			frame->ether_type =
2939 			    IFNET_KEEPALIVE_OFFLOAD_FRAME_ETHERTYPE_IPV4;
2940 			frame->interval = inp->inp_keepalive_interval;
2941 			switch (inp->inp_keepalive_type) {
2942 			case UDP_KEEPALIVE_OFFLOAD_TYPE_AIRPLAY:
2943 				frame->type =
2944 				    IFNET_KEEPALIVE_OFFLOAD_FRAME_AIRPLAY;
2945 				break;
2946 			default:
2947 				break;
2948 			}
2949 			data = mtod(m, u_int8_t *);
2950 			bzero(data, sizeof(struct udpiphdr));
2951 			ip = (__typeof__(ip))(void *)data;
2952 			udp = (__typeof__(udp))(void *) (data +
2953 			    sizeof(struct ip));
2954 			m->m_len = sizeof(struct udpiphdr);
2955 			data = data + sizeof(struct udpiphdr);
2956 			if (inp->inp_keepalive_datalen > 0 &&
2957 			    inp->inp_keepalive_data != NULL) {
2958 				bcopy(inp->inp_keepalive_data, data,
2959 				    inp->inp_keepalive_datalen);
2960 				m->m_len += inp->inp_keepalive_datalen;
2961 			}
2962 			m->m_pkthdr.len = m->m_len;
2963 
2964 			ip->ip_v = IPVERSION;
2965 			ip->ip_hl = (sizeof(struct ip) >> 2);
2966 			ip->ip_p = IPPROTO_UDP;
2967 			ip->ip_len = htons(sizeof(struct udpiphdr) +
2968 			    (u_short)inp->inp_keepalive_datalen);
2969 			ip->ip_ttl = inp->inp_ip_ttl;
2970 			ip->ip_tos |= (inp->inp_ip_tos & ~IPTOS_ECN_MASK);
2971 			ip->ip_src = inp->inp_laddr;
2972 			ip->ip_dst = inp->inp_faddr;
2973 			ip->ip_sum = in_cksum_hdr_opt(ip);
2974 
2975 			udp->uh_sport = inp->inp_lport;
2976 			udp->uh_dport = inp->inp_fport;
2977 			udp->uh_ulen = htons(sizeof(struct udphdr) +
2978 			    (u_short)inp->inp_keepalive_datalen);
2979 
2980 			if (!(inp->inp_flags & INP_UDP_NOCKSUM)) {
2981 				udp->uh_sum = in_pseudo(ip->ip_src.s_addr,
2982 				    ip->ip_dst.s_addr,
2983 				    htons(sizeof(struct udphdr) +
2984 				    (u_short)inp->inp_keepalive_datalen +
2985 				    IPPROTO_UDP));
2986 				m->m_pkthdr.csum_flags =
2987 				    (CSUM_UDP | CSUM_ZERO_INVERT);
2988 				m->m_pkthdr.csum_data = offsetof(struct udphdr,
2989 				    uh_sum);
2990 			}
2991 			m->m_pkthdr.pkt_proto = IPPROTO_UDP;
2992 			in_delayed_cksum(m);
2993 			bcopy(m->m_data, frame->data + frame_data_offset,
2994 			    m->m_len);
2995 		} else {
2996 			struct ip6_hdr *ip6;
2997 			struct udphdr *udp6;
2998 
2999 			VERIFY(inp->inp_vflag & INP_IPV6);
3000 			frame = &frames_array[frame_index];
3001 			frame->length = (uint8_t)(frame_data_offset +
3002 			    sizeof(struct ip6_hdr) +
3003 			    sizeof(struct udphdr) +
3004 			    inp->inp_keepalive_datalen);
3005 			frame->ether_type =
3006 			    IFNET_KEEPALIVE_OFFLOAD_FRAME_ETHERTYPE_IPV6;
3007 			frame->interval = inp->inp_keepalive_interval;
3008 			switch (inp->inp_keepalive_type) {
3009 			case UDP_KEEPALIVE_OFFLOAD_TYPE_AIRPLAY:
3010 				frame->type =
3011 				    IFNET_KEEPALIVE_OFFLOAD_FRAME_AIRPLAY;
3012 				break;
3013 			default:
3014 				break;
3015 			}
3016 			data = mtod(m, u_int8_t *);
3017 			bzero(data, sizeof(struct ip6_hdr) + sizeof(struct udphdr));
3018 			ip6 = (__typeof__(ip6))(void *)data;
3019 			udp6 = (__typeof__(udp6))(void *)(data +
3020 			    sizeof(struct ip6_hdr));
3021 			m->m_len = sizeof(struct ip6_hdr) +
3022 			    sizeof(struct udphdr);
3023 			data = data + (sizeof(struct ip6_hdr) +
3024 			    sizeof(struct udphdr));
3025 			if (inp->inp_keepalive_datalen > 0 &&
3026 			    inp->inp_keepalive_data != NULL) {
3027 				bcopy(inp->inp_keepalive_data, data,
3028 				    inp->inp_keepalive_datalen);
3029 				m->m_len += inp->inp_keepalive_datalen;
3030 			}
3031 			m->m_pkthdr.len = m->m_len;
3032 			ip6->ip6_flow = inp->inp_flow & IPV6_FLOWINFO_MASK;
3033 			ip6->ip6_flow = ip6->ip6_flow & ~IPV6_FLOW_ECN_MASK;
3034 			ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
3035 			ip6->ip6_vfc |= IPV6_VERSION;
3036 			ip6->ip6_nxt = IPPROTO_UDP;
3037 			ip6->ip6_hlim = (uint8_t)ip6_defhlim;
3038 			ip6->ip6_plen = htons(sizeof(struct udphdr) +
3039 			    (u_short)inp->inp_keepalive_datalen);
3040 			ip6->ip6_src = inp->in6p_laddr;
3041 			if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) {
3042 				ip6->ip6_src.s6_addr16[1] = 0;
3043 			}
3044 
3045 			ip6->ip6_dst = inp->in6p_faddr;
3046 			if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
3047 				ip6->ip6_dst.s6_addr16[1] = 0;
3048 			}
3049 
3050 			udp6->uh_sport = inp->in6p_lport;
3051 			udp6->uh_dport = inp->in6p_fport;
3052 			udp6->uh_ulen = htons(sizeof(struct udphdr) +
3053 			    (u_short)inp->inp_keepalive_datalen);
3054 			if (!(inp->inp_flags & INP_UDP_NOCKSUM)) {
3055 				udp6->uh_sum = in6_pseudo(&ip6->ip6_src,
3056 				    &ip6->ip6_dst,
3057 				    htonl(sizeof(struct udphdr) +
3058 				    (u_short)inp->inp_keepalive_datalen +
3059 				    IPPROTO_UDP));
3060 				m->m_pkthdr.csum_flags =
3061 				    (CSUM_UDPIPV6 | CSUM_ZERO_INVERT);
3062 				m->m_pkthdr.csum_data = offsetof(struct udphdr,
3063 				    uh_sum);
3064 			}
3065 			m->m_pkthdr.pkt_proto = IPPROTO_UDP;
3066 			in6_delayed_cksum(m);
3067 			bcopy(m->m_data, frame->data + frame_data_offset,
3068 			    m->m_len);
3069 		}
3070 		if (m != NULL) {
3071 			m_freem(m);
3072 			m = NULL;
3073 		}
3074 		frame_index++;
3075 		udp_unlock(so, 1, 0);
3076 	}
3077 	lck_rw_done(&udbinfo.ipi_lock);
3078 	*used_frames_count = frame_index;
3079 }
3080 
3081 int
udp_defunct(struct socket * so)3082 udp_defunct(struct socket *so)
3083 {
3084 	struct ip_moptions *imo;
3085 	struct inpcb *inp;
3086 
3087 	inp = sotoinpcb(so);
3088 	if (inp == NULL) {
3089 		return EINVAL;
3090 	}
3091 
3092 	imo = inp->inp_moptions;
3093 	if (imo != NULL) {
3094 		struct proc *p = current_proc();
3095 
3096 		SODEFUNCTLOG("%s[%d, %s]: defuncting so 0x%llu drop multicast memberships",
3097 		    __func__, proc_pid(p), proc_best_name(p),
3098 		    so->so_gencnt);
3099 
3100 		inp->inp_moptions = NULL;
3101 
3102 		IMO_REMREF(imo);
3103 	}
3104 
3105 	return 0;
3106 }
3107