xref: /netbsd-src/sys/netinet/ip_carp.c (revision aef5eb5f59cdfe8314f1b5f78ac04eb144e44010)
1 /*	$NetBSD: ip_carp.c,v 1.117 2022/09/02 23:48:11 thorpej Exp $	*/
2 /*	$OpenBSD: ip_carp.c,v 1.113 2005/11/04 08:11:54 mcbride Exp $	*/
3 
4 /*
5  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
6  * Copyright (c) 2003 Ryan McBride. All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
27  * THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #ifdef _KERNEL_OPT
31 #include "opt_inet.h"
32 #include "opt_mbuftrace.h"
33 #endif
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: ip_carp.c,v 1.117 2022/09/02 23:48:11 thorpej Exp $");
37 
38 /*
39  * TODO:
40  *	- iface reconfigure
41  *	- support for hardware checksum calculations;
42  *
43  */
44 
45 #include <sys/param.h>
46 #include <sys/proc.h>
47 #include <sys/mbuf.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/callout.h>
51 #include <sys/ioctl.h>
52 #include <sys/errno.h>
53 #include <sys/device.h>
54 #include <sys/time.h>
55 #include <sys/kernel.h>
56 #include <sys/kauth.h>
57 #include <sys/sysctl.h>
58 #include <sys/ucred.h>
59 #include <sys/syslog.h>
60 #include <sys/acct.h>
61 #include <sys/cprng.h>
62 #include <sys/cpu.h>
63 #include <sys/pserialize.h>
64 #include <sys/psref.h>
65 
66 #include <net/if.h>
67 #include <net/pfil.h>
68 #include <net/if_types.h>
69 #include <net/if_ether.h>
70 #include <net/route.h>
71 #include <net/net_stats.h>
72 #include <netinet/if_inarp.h>
73 #include <netinet/wqinput.h>
74 
75 #ifdef INET
76 #include <netinet/in.h>
77 #include <netinet/in_systm.h>
78 #include <netinet/in_var.h>
79 #include <netinet/ip.h>
80 #include <netinet/ip_var.h>
81 
82 #include <net/if_dl.h>
83 #endif
84 
85 #ifdef INET6
86 #include <netinet/icmp6.h>
87 #include <netinet/ip6.h>
88 #include <netinet6/ip6_var.h>
89 #include <netinet6/nd6.h>
90 #include <netinet6/scope6_var.h>
91 #include <netinet6/in6_var.h>
92 #endif
93 
94 #include <net/bpf.h>
95 
96 #include <sys/sha1.h>
97 
98 #include <netinet/ip_carp.h>
99 
100 #include "ioconf.h"
101 
102 struct carp_mc_entry {
103 	LIST_ENTRY(carp_mc_entry)	mc_entries;
104 	union {
105 		struct ether_multi	*mcu_enm;
106 	} mc_u;
107 	struct sockaddr_storage		mc_addr;
108 };
109 #define	mc_enm	mc_u.mcu_enm
110 
111 struct carp_softc {
112 	struct ethercom sc_ac;
113 #define	sc_if		sc_ac.ec_if
114 #define	sc_carpdev	sc_ac.ec_if.if_carpdev
115 	void *sc_linkstate_hook;
116 	int ah_cookie;
117 	int lh_cookie;
118 	struct ip_moptions sc_imo;
119 #ifdef INET6
120 	struct ip6_moptions sc_im6o;
121 #endif /* INET6 */
122 	TAILQ_ENTRY(carp_softc) sc_list;
123 
124 	enum { INIT = 0, BACKUP, MASTER }	sc_state;
125 
126 	int sc_suppress;
127 	int sc_bow_out;
128 
129 	int sc_sendad_errors;
130 #define CARP_SENDAD_MAX_ERRORS	3
131 	int sc_sendad_success;
132 #define CARP_SENDAD_MIN_SUCCESS 3
133 
134 	int sc_vhid;
135 	int sc_advskew;
136 	int sc_naddrs;
137 	int sc_naddrs6;
138 	int sc_advbase;		/* seconds */
139 	int sc_init_counter;
140 	u_int64_t sc_counter;
141 
142 	/* authentication */
143 #define CARP_HMAC_PAD	64
144 	unsigned char sc_key[CARP_KEY_LEN];
145 	unsigned char sc_pad[CARP_HMAC_PAD];
146 	SHA1_CTX sc_sha1;
147 	u_int32_t sc_hashkey[2];
148 
149 	struct callout sc_ad_tmo;	/* advertisement timeout */
150 	struct callout sc_md_tmo;	/* master down timeout */
151 	struct callout sc_md6_tmo;	/* master down timeout */
152 
153 	LIST_HEAD(__carp_mchead, carp_mc_entry)	carp_mc_listhead;
154 };
155 
156 int carp_suppress_preempt = 0;
157 static int carp_opts[CARPCTL_MAXID] = { 0, 1, 0, 0, 0 };	/* XXX for now */
158 
159 static percpu_t *carpstat_percpu;
160 
161 #define	CARP_STATINC(x)		_NET_STATINC(carpstat_percpu, x)
162 
163 #ifdef MBUFTRACE
164 static struct mowner carp_proto_mowner_rx = MOWNER_INIT("carp", "rx");
165 static struct mowner carp_proto_mowner_tx = MOWNER_INIT("carp", "tx");
166 static struct mowner carp_proto6_mowner_rx = MOWNER_INIT("carp6", "rx");
167 static struct mowner carp_proto6_mowner_tx = MOWNER_INIT("carp6", "tx");
168 #endif
169 
170 struct carp_if {
171 	TAILQ_HEAD(, carp_softc) vhif_vrs;
172 	int vhif_nvrs;
173 
174 	struct ifnet *vhif_ifp;
175 };
176 
177 #define	CARP_LOG(sc, s)							\
178 	if (carp_opts[CARPCTL_LOG]) {					\
179 		if (sc)							\
180 			log(LOG_INFO, "%s: ",				\
181 			    (sc)->sc_if.if_xname);			\
182 		else							\
183 			log(LOG_INFO, "carp: ");			\
184 		addlog s;						\
185 		addlog("\n");						\
186 	}
187 
188 static void	carp_hmac_prepare(struct carp_softc *);
189 static void	carp_hmac_generate(struct carp_softc *, u_int32_t *,
190 		    unsigned char *);
191 static int	carp_hmac_verify(struct carp_softc *, u_int32_t *,
192 		    unsigned char *);
193 static void	carp_setroute(struct carp_softc *, int);
194 static void	carp_proto_input_c(struct mbuf *, struct carp_header *,
195 		    sa_family_t);
196 static void	carpdetach(struct carp_softc *);
197 static void	carp_prepare_ad(struct mbuf *, struct carp_softc *,
198 		    struct carp_header *);
199 static void	carp_send_ad_all(void);
200 static void	carp_send_ad(void *);
201 static void	carp_send_arp(struct carp_softc *);
202 static void	carp_master_down(void *);
203 static int	carp_ioctl(struct ifnet *, u_long, void *);
204 static void	carp_start(struct ifnet *);
205 static void	carp_setrun(struct carp_softc *, sa_family_t);
206 static void	carp_set_state(struct carp_softc *, int);
207 static int	carp_addrcount(struct carp_if *, struct in_ifaddr *, int);
208 enum	{ CARP_COUNT_MASTER, CARP_COUNT_RUNNING };
209 
210 static void	carp_multicast_cleanup(struct carp_softc *);
211 static int	carp_set_ifp(struct carp_softc *, struct ifnet *);
212 static void	carp_set_enaddr(struct carp_softc *);
213 #if 0
214 static void	carp_addr_updated(void *);
215 #endif
216 static u_int32_t	carp_hash(struct carp_softc *, u_char *);
217 static int	carp_set_addr(struct carp_softc *, struct sockaddr_in *);
218 static int	carp_join_multicast(struct carp_softc *);
219 #ifdef INET6
220 static void	carp_send_na(struct carp_softc *);
221 static int	carp_set_addr6(struct carp_softc *, struct sockaddr_in6 *);
222 static int	carp_join_multicast6(struct carp_softc *);
223 #endif
224 static int	carp_clone_create(struct if_clone *, int);
225 static int	carp_clone_destroy(struct ifnet *);
226 static int	carp_ether_addmulti(struct carp_softc *, struct ifreq *);
227 static int	carp_ether_delmulti(struct carp_softc *, struct ifreq *);
228 static void	carp_ether_purgemulti(struct carp_softc *);
229 static void	carp_update_link_state(struct carp_softc *sc);
230 
231 static void	sysctl_net_inet_carp_setup(struct sysctllog **);
232 
233 /* workqueue-based pr_input */
234 static struct wqinput *carp_wqinput;
235 static void _carp_proto_input(struct mbuf *, int, int);
236 #ifdef INET6
237 static struct wqinput *carp6_wqinput;
238 static void _carp6_proto_input(struct mbuf *, int, int);
239 #endif
240 
241 struct if_clone carp_cloner =
242     IF_CLONE_INITIALIZER("carp", carp_clone_create, carp_clone_destroy);
243 
244 static __inline u_int16_t
245 carp_cksum(struct mbuf *m, int len)
246 {
247 	return (in_cksum(m, len));
248 }
249 
250 #ifdef INET6
251 static __inline u_int16_t
252 carp6_cksum(struct mbuf *m, uint32_t off, uint32_t len)
253 {
254 	return (in6_cksum(m, IPPROTO_CARP, off, len));
255 }
256 #endif
257 
258 static void
259 carp_hmac_prepare(struct carp_softc *sc)
260 {
261 	u_int8_t carp_version = CARP_VERSION, type = CARP_ADVERTISEMENT;
262 	u_int8_t vhid = sc->sc_vhid & 0xff;
263 	SHA1_CTX sha1ctx;
264 	u_int32_t kmd[5];
265 	struct ifaddr *ifa;
266 	int i, found;
267 	struct in_addr last, cur, in;
268 #ifdef INET6
269 	struct in6_addr last6, cur6, in6;
270 #endif /* INET6 */
271 
272 	/* compute ipad from key */
273 	memset(sc->sc_pad, 0, sizeof(sc->sc_pad));
274 	memcpy(sc->sc_pad, sc->sc_key, sizeof(sc->sc_key));
275 	for (i = 0; i < sizeof(sc->sc_pad); i++)
276 		sc->sc_pad[i] ^= 0x36;
277 
278 	/* precompute first part of inner hash */
279 	SHA1Init(&sc->sc_sha1);
280 	SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
281 	SHA1Update(&sc->sc_sha1, (void *)&carp_version, sizeof(carp_version));
282 	SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
283 
284 	/* generate a key for the arpbalance hash, before the vhid is hashed */
285 	memcpy(&sha1ctx, &sc->sc_sha1, sizeof(sha1ctx));
286 	SHA1Final((unsigned char *)kmd, &sha1ctx);
287 	sc->sc_hashkey[0] = kmd[0] ^ kmd[1];
288 	sc->sc_hashkey[1] = kmd[2] ^ kmd[3];
289 
290 	/* the rest of the precomputation */
291 	SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
292 
293 	/* Hash the addresses from smallest to largest, not interface order */
294 #ifdef INET
295 	cur.s_addr = 0;
296 	do {
297 		int s;
298 		found = 0;
299 		last = cur;
300 		cur.s_addr = 0xffffffff;
301 		s = pserialize_read_enter();
302 		IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
303 			in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr;
304 			if (ifa->ifa_addr->sa_family == AF_INET &&
305 			    ntohl(in.s_addr) > ntohl(last.s_addr) &&
306 			    ntohl(in.s_addr) < ntohl(cur.s_addr)) {
307 				cur.s_addr = in.s_addr;
308 				found++;
309 			}
310 		}
311 		pserialize_read_exit(s);
312 		if (found)
313 			SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur));
314 	} while (found);
315 #endif /* INET */
316 
317 #ifdef INET6
318 	memset(&cur6, 0x00, sizeof(cur6));
319 	do {
320 		int s;
321 		found = 0;
322 		last6 = cur6;
323 		memset(&cur6, 0xff, sizeof(cur6));
324 		s = pserialize_read_enter();
325 		IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
326 			in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
327 			if (IN6_IS_ADDR_LINKLOCAL(&in6))
328 				in6.s6_addr16[1] = 0;
329 			if (ifa->ifa_addr->sa_family == AF_INET6 &&
330 			    memcmp(&in6, &last6, sizeof(in6)) > 0 &&
331 			    memcmp(&in6, &cur6, sizeof(in6)) < 0) {
332 				cur6 = in6;
333 				found++;
334 			}
335 		}
336 		pserialize_read_exit(s);
337 		if (found)
338 			SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6));
339 	} while (found);
340 #endif /* INET6 */
341 
342 	/* convert ipad to opad */
343 	for (i = 0; i < sizeof(sc->sc_pad); i++)
344 		sc->sc_pad[i] ^= 0x36 ^ 0x5c;
345 }
346 
347 static void
348 carp_hmac_generate(struct carp_softc *sc, u_int32_t counter[2],
349     unsigned char md[20])
350 {
351 	SHA1_CTX sha1ctx;
352 
353 	/* fetch first half of inner hash */
354 	memcpy(&sha1ctx, &sc->sc_sha1, sizeof(sha1ctx));
355 
356 	SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
357 	SHA1Final(md, &sha1ctx);
358 
359 	/* outer hash */
360 	SHA1Init(&sha1ctx);
361 	SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
362 	SHA1Update(&sha1ctx, md, 20);
363 	SHA1Final(md, &sha1ctx);
364 }
365 
366 static int
367 carp_hmac_verify(struct carp_softc *sc, u_int32_t counter[2],
368     unsigned char md[20])
369 {
370 	unsigned char md2[20];
371 
372 	carp_hmac_generate(sc, counter, md2);
373 
374 	return (memcmp(md, md2, sizeof(md2)));
375 }
376 
377 static void
378 carp_setroute(struct carp_softc *sc, int cmd)
379 {
380 	struct ifaddr *ifa;
381 	int s, bound;
382 
383 	KERNEL_LOCK(1, NULL);
384 	bound = curlwp_bind();
385 	s = pserialize_read_enter();
386 	IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
387 		struct psref psref;
388 		ifa_acquire(ifa, &psref);
389 		pserialize_read_exit(s);
390 
391 		switch (ifa->ifa_addr->sa_family) {
392 		case AF_INET: {
393 			int count = 0;
394 			struct rtentry *rt;
395 			int hr_otherif, nr_ourif;
396 
397 			/*
398 			 * Avoid screwing with the routes if there are other
399 			 * carp interfaces which are master and have the same
400 			 * address.
401 			 */
402 			if (sc->sc_carpdev != NULL &&
403 			    sc->sc_carpdev->if_carp != NULL) {
404 				count = carp_addrcount(
405 				    (struct carp_if *)sc->sc_carpdev->if_carp,
406 				    ifatoia(ifa), CARP_COUNT_MASTER);
407 				if ((cmd == RTM_ADD && count != 1) ||
408 				    (cmd == RTM_DELETE && count != 0))
409 					goto next;
410 			}
411 
412 			/* Remove the existing host route, if any */
413 			rtrequest(RTM_DELETE, ifa->ifa_addr,
414 			    ifa->ifa_addr, ifa->ifa_netmask,
415 			    RTF_HOST, NULL);
416 
417 			rt = NULL;
418 			(void)rtrequest(RTM_GET, ifa->ifa_addr, ifa->ifa_addr,
419 			    ifa->ifa_netmask, RTF_HOST, &rt);
420 			hr_otherif = (rt && rt->rt_ifp != &sc->sc_if &&
421 			    (rt->rt_flags & RTF_CONNECTED));
422 			if (rt != NULL) {
423 				rt_unref(rt);
424 				rt = NULL;
425 			}
426 
427 			/* Check for a network route on our interface */
428 
429 			rt = NULL;
430 			(void)rtrequest(RTM_GET, ifa->ifa_addr, ifa->ifa_addr,
431 			    ifa->ifa_netmask, 0, &rt);
432 			nr_ourif = (rt && rt->rt_ifp == &sc->sc_if);
433 
434 			switch (cmd) {
435 			case RTM_ADD:
436 				if (hr_otherif) {
437 					ifa->ifa_rtrequest = NULL;
438 					ifa->ifa_flags &= ~RTF_CONNECTED;
439 
440 					rtrequest(RTM_ADD, ifa->ifa_addr,
441 					    ifa->ifa_addr, ifa->ifa_netmask,
442 					    RTF_UP | RTF_HOST, NULL);
443 				}
444 				if (!hr_otherif || nr_ourif || !rt) {
445 					if (nr_ourif &&
446 					    (rt->rt_flags & RTF_CONNECTED) == 0)
447 						rtrequest(RTM_DELETE,
448 						    ifa->ifa_addr,
449 						    ifa->ifa_addr,
450 						    ifa->ifa_netmask, 0, NULL);
451 
452 					ifa->ifa_rtrequest = arp_rtrequest;
453 					ifa->ifa_flags |= RTF_CONNECTED;
454 
455 					if (rtrequest(RTM_ADD, ifa->ifa_addr,
456 					    ifa->ifa_addr, ifa->ifa_netmask, 0,
457 					    NULL) == 0)
458 						ifa->ifa_flags |= IFA_ROUTE;
459 				}
460 				break;
461 			case RTM_DELETE:
462 				break;
463 			default:
464 				break;
465 			}
466 			if (rt != NULL) {
467 				rt_unref(rt);
468 				rt = NULL;
469 			}
470 			break;
471 		}
472 
473 #ifdef INET6
474 		case AF_INET6:
475 			if (cmd == RTM_ADD)
476 				in6_ifaddlocal(ifa);
477 			else
478 				in6_ifremlocal(ifa);
479 			break;
480 #endif /* INET6 */
481 		default:
482 			break;
483 		}
484 	next:
485 		s = pserialize_read_enter();
486 		ifa_release(ifa, &psref);
487 	}
488 	pserialize_read_exit(s);
489 	curlwp_bindx(bound);
490 	KERNEL_UNLOCK_ONE(NULL);
491 }
492 
493 /*
494  * process input packet.
495  * we have rearranged checks order compared to the rfc,
496  * but it seems more efficient this way or not possible otherwise.
497  */
498 static void
499 _carp_proto_input(struct mbuf *m, int hlen, int proto)
500 {
501 	struct ip *ip = mtod(m, struct ip *);
502 	struct carp_softc *sc = NULL;
503 	struct carp_header *ch;
504 	int iplen, len;
505 	struct ifnet *rcvif;
506 
507 	CARP_STATINC(CARP_STAT_IPACKETS);
508 	MCLAIM(m, &carp_proto_mowner_rx);
509 
510 	if (!carp_opts[CARPCTL_ALLOW]) {
511 		m_freem(m);
512 		return;
513 	}
514 
515 	rcvif = m_get_rcvif_NOMPSAFE(m);
516 	/* check if received on a valid carp interface */
517 	if (rcvif->if_type != IFT_CARP) {
518 		CARP_STATINC(CARP_STAT_BADIF);
519 		CARP_LOG(sc, ("packet received on non-carp interface: %s",
520 		    rcvif->if_xname));
521 		m_freem(m);
522 		return;
523 	}
524 
525 	/* verify that the IP TTL is 255.  */
526 	if (ip->ip_ttl != CARP_DFLTTL) {
527 		CARP_STATINC(CARP_STAT_BADTTL);
528 		CARP_LOG(sc, ("received ttl %d != %d on %s", ip->ip_ttl,
529 		    CARP_DFLTTL, rcvif->if_xname));
530 		m_freem(m);
531 		return;
532 	}
533 
534 	/*
535 	 * verify that the received packet length is
536 	 * equal to the CARP header
537 	 */
538 	iplen = ip->ip_hl << 2;
539 	len = iplen + sizeof(*ch);
540 	if (len > m->m_pkthdr.len) {
541 		CARP_STATINC(CARP_STAT_BADLEN);
542 		CARP_LOG(sc, ("packet too short %d on %s", m->m_pkthdr.len,
543 		    rcvif->if_xname));
544 		m_freem(m);
545 		return;
546 	}
547 
548 	if ((m = m_pullup(m, len)) == NULL) {
549 		CARP_STATINC(CARP_STAT_HDROPS);
550 		return;
551 	}
552 	ip = mtod(m, struct ip *);
553 	ch = (struct carp_header *)((char *)ip + iplen);
554 	/* verify the CARP checksum */
555 	m->m_data += iplen;
556 	if (carp_cksum(m, len - iplen)) {
557 		CARP_STATINC(CARP_STAT_BADSUM);
558 		CARP_LOG(sc, ("checksum failed on %s",
559 		    rcvif->if_xname));
560 		m_freem(m);
561 		return;
562 	}
563 	m->m_data -= iplen;
564 
565 	carp_proto_input_c(m, ch, AF_INET);
566 }
567 
568 void
569 carp_proto_input(struct mbuf *m, int off, int proto)
570 {
571 
572 	wqinput_input(carp_wqinput, m, 0, 0);
573 }
574 
575 #ifdef INET6
576 static void
577 _carp6_proto_input(struct mbuf *m, int off, int proto)
578 {
579 	struct carp_softc *sc = NULL;
580 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
581 	struct carp_header *ch;
582 	u_int len;
583 	struct ifnet *rcvif;
584 
585 	CARP_STATINC(CARP_STAT_IPACKETS6);
586 	MCLAIM(m, &carp_proto6_mowner_rx);
587 
588 	if (!carp_opts[CARPCTL_ALLOW]) {
589 		m_freem(m);
590 		return;
591 	}
592 
593 	rcvif = m_get_rcvif_NOMPSAFE(m);
594 
595 	/* check if received on a valid carp interface */
596 	if (rcvif->if_type != IFT_CARP) {
597 		CARP_STATINC(CARP_STAT_BADIF);
598 		CARP_LOG(sc, ("packet received on non-carp interface: %s",
599 		    rcvif->if_xname));
600 		m_freem(m);
601 		return;
602 	}
603 
604 	/* verify that the IP TTL is 255 */
605 	if (ip6->ip6_hlim != CARP_DFLTTL) {
606 		CARP_STATINC(CARP_STAT_BADTTL);
607 		CARP_LOG(sc, ("received ttl %d != %d on %s", ip6->ip6_hlim,
608 		    CARP_DFLTTL, rcvif->if_xname));
609 		m_freem(m);
610 		return;
611 	}
612 
613 	/* verify that we have a complete carp packet */
614 	len = m->m_len;
615 	M_REGION_GET(ch, struct carp_header *, m, off, sizeof(*ch));
616 	if (ch == NULL) {
617 		CARP_STATINC(CARP_STAT_BADLEN);
618 		CARP_LOG(sc, ("packet size %u too small", len));
619 		return;
620 	}
621 
622 	/* verify the CARP checksum */
623 	if (carp6_cksum(m, off, sizeof(*ch))) {
624 		CARP_STATINC(CARP_STAT_BADSUM);
625 		CARP_LOG(sc, ("checksum failed, on %s", rcvif->if_xname));
626 		m_freem(m);
627 		return;
628 	}
629 
630 	carp_proto_input_c(m, ch, AF_INET6);
631 	return;
632 }
633 
634 int
635 carp6_proto_input(struct mbuf **mp, int *offp, int proto)
636 {
637 
638 	wqinput_input(carp6_wqinput, *mp, *offp, proto);
639 
640 	return IPPROTO_DONE;
641 }
642 #endif /* INET6 */
643 
644 static void
645 carp_proto_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
646 {
647 	struct carp_softc *sc;
648 	u_int64_t tmp_counter;
649 	struct timeval sc_tv, ch_tv;
650 
651 	TAILQ_FOREACH(sc, &((struct carp_if *)
652 	    m_get_rcvif_NOMPSAFE(m)->if_carpdev->if_carp)->vhif_vrs, sc_list)
653 		if (sc->sc_vhid == ch->carp_vhid)
654 			break;
655 
656 	if (!sc || (sc->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) !=
657 	    (IFF_UP|IFF_RUNNING)) {
658 		CARP_STATINC(CARP_STAT_BADVHID);
659 		m_freem(m);
660 		return;
661 	}
662 
663 	/*
664 	 * Check if our own advertisement was duplicated
665 	 * from a non simplex interface.
666 	 * XXX If there is no address on our physical interface
667 	 * there is no way to distinguish our ads from the ones
668 	 * another carp host might have sent us.
669 	 */
670 	if ((sc->sc_carpdev->if_flags & IFF_SIMPLEX) == 0) {
671 		struct sockaddr sa;
672 		struct ifaddr *ifa;
673 		int s;
674 
675 		memset(&sa, 0, sizeof(sa));
676 		sa.sa_family = af;
677 		s = pserialize_read_enter();
678 		ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
679 
680 		if (ifa && af == AF_INET) {
681 			struct ip *ip = mtod(m, struct ip *);
682 			if (ip->ip_src.s_addr ==
683 					ifatoia(ifa)->ia_addr.sin_addr.s_addr) {
684 				pserialize_read_exit(s);
685 				m_freem(m);
686 				return;
687 			}
688 		}
689 #ifdef INET6
690 		if (ifa && af == AF_INET6) {
691 			struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
692 			struct in6_addr in6_src, in6_found;
693 
694 			in6_src = ip6->ip6_src;
695 			in6_found = ifatoia6(ifa)->ia_addr.sin6_addr;
696 			if (IN6_IS_ADDR_LINKLOCAL(&in6_src))
697 				in6_src.s6_addr16[1] = 0;
698 			if (IN6_IS_ADDR_LINKLOCAL(&in6_found))
699 				in6_found.s6_addr16[1] = 0;
700 			if (IN6_ARE_ADDR_EQUAL(&in6_src, &in6_found)) {
701 				pserialize_read_exit(s);
702 				m_freem(m);
703 				return;
704 			}
705 		}
706 #endif /* INET6 */
707 		pserialize_read_exit(s);
708 	}
709 
710 	nanotime(&sc->sc_if.if_lastchange);
711 	if_statadd2(&sc->sc_if, if_ipackets, 1, if_ibytes, m->m_pkthdr.len);
712 
713 	/* verify the CARP version. */
714 	if (ch->carp_version != CARP_VERSION) {
715 		CARP_STATINC(CARP_STAT_BADVER);
716 		if_statinc(&sc->sc_if, if_ierrors);
717 		CARP_LOG(sc, ("invalid version %d != %d",
718 		    ch->carp_version, CARP_VERSION));
719 		m_freem(m);
720 		return;
721 	}
722 
723 	/* verify the hash */
724 	if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
725 		struct ip *ip;
726 		char ipbuf[INET_ADDRSTRLEN];
727 #ifdef INET6
728 		struct ip6_hdr *ip6;
729 		char ip6buf[INET6_ADDRSTRLEN];
730 #endif
731 
732 		CARP_STATINC(CARP_STAT_BADAUTH);
733 		if_statinc(&sc->sc_if, if_ierrors);
734 
735 		switch(af) {
736 		case AF_INET:
737 			ip = mtod(m, struct ip *);
738 			CARP_LOG(sc, ("incorrect hash from %s",
739 			    IN_PRINT(ipbuf, &ip->ip_src)));
740 			break;
741 
742 #ifdef INET6
743 		case AF_INET6:
744 			ip6 = mtod(m, struct ip6_hdr *);
745 			CARP_LOG(sc, ("incorrect hash from %s",
746 			    IN6_PRINT(ip6buf, &ip6->ip6_src)));
747 			break;
748 #endif
749 
750 		default: CARP_LOG(sc, ("incorrect hash"));
751 			break;
752 		}
753 		m_freem(m);
754 		return;
755 	}
756 
757 	tmp_counter = ntohl(ch->carp_counter[0]);
758 	tmp_counter = tmp_counter<<32;
759 	tmp_counter += ntohl(ch->carp_counter[1]);
760 
761 	/* XXX Replay protection goes here */
762 
763 	sc->sc_init_counter = 0;
764 	sc->sc_counter = tmp_counter;
765 
766 
767 	sc_tv.tv_sec = sc->sc_advbase;
768 	if (carp_suppress_preempt && sc->sc_advskew <  240)
769 		sc_tv.tv_usec = 240 * 1000000 / 256;
770 	else
771 		sc_tv.tv_usec = sc->sc_advskew * 1000000 / 256;
772 	ch_tv.tv_sec = ch->carp_advbase;
773 	ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
774 
775 	switch (sc->sc_state) {
776 	case INIT:
777 		break;
778 	case MASTER:
779 		/*
780 		 * If we receive an advertisement from a backup who's going to
781 		 * be more frequent than us, go into BACKUP state.
782 		 */
783 		if (timercmp(&sc_tv, &ch_tv, >) ||
784 		    timercmp(&sc_tv, &ch_tv, ==)) {
785 			callout_stop(&sc->sc_ad_tmo);
786 			CARP_LOG(sc, ("MASTER -> BACKUP (more frequent advertisement received)"));
787 			carp_set_state(sc, BACKUP);
788 			carp_setrun(sc, 0);
789 			carp_setroute(sc, RTM_DELETE);
790 		}
791 		break;
792 	case BACKUP:
793 		/*
794 		 * If we're pre-empting masters who advertise slower than us,
795 		 * and this one claims to be slower, treat him as down.
796 		 */
797 		if (carp_opts[CARPCTL_PREEMPT] && timercmp(&sc_tv, &ch_tv, <)) {
798 			CARP_LOG(sc, ("BACKUP -> MASTER (preempting a slower master)"));
799 			carp_master_down(sc);
800 			break;
801 		}
802 
803 		/*
804 		 *  If the master is going to advertise at such a low frequency
805 		 *  that he's guaranteed to time out, we'd might as well just
806 		 *  treat him as timed out now.
807 		 */
808 		sc_tv.tv_sec = sc->sc_advbase * 3;
809 		if (timercmp(&sc_tv, &ch_tv, <)) {
810 			CARP_LOG(sc, ("BACKUP -> MASTER (master timed out)"));
811 			carp_master_down(sc);
812 			break;
813 		}
814 
815 		/*
816 		 * Otherwise, we reset the counter and wait for the next
817 		 * advertisement.
818 		 */
819 		carp_setrun(sc, af);
820 		break;
821 	}
822 
823 	m_freem(m);
824 	return;
825 }
826 
827 /*
828  * Interface side of the CARP implementation.
829  */
830 
831 /* ARGSUSED */
832 void
833 carpattach(int n)
834 {
835 	if_clone_attach(&carp_cloner);
836 
837 	carpstat_percpu = percpu_alloc(sizeof(uint64_t) * CARP_NSTATS);
838 }
839 
840 static int
841 carp_clone_create(struct if_clone *ifc, int unit)
842 {
843 	extern int ifqmaxlen;
844 	struct carp_softc *sc;
845 	struct ifnet *ifp;
846 
847 	sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT|M_ZERO);
848 	if (!sc)
849 		return (ENOMEM);
850 
851 	sc->sc_suppress = 0;
852 	sc->sc_advbase = CARP_DFLTINTV;
853 	sc->sc_vhid = -1;	/* required setting */
854 	sc->sc_advskew = 0;
855 	sc->sc_init_counter = 1;
856 	sc->sc_naddrs = sc->sc_naddrs6 = 0;
857 #ifdef INET6
858 	sc->sc_im6o.im6o_multicast_hlim = CARP_DFLTTL;
859 #endif /* INET6 */
860 
861 	callout_init(&sc->sc_ad_tmo, 0);
862 	callout_init(&sc->sc_md_tmo, 0);
863 	callout_init(&sc->sc_md6_tmo, 0);
864 
865 	callout_setfunc(&sc->sc_ad_tmo, carp_send_ad, sc);
866 	callout_setfunc(&sc->sc_md_tmo, carp_master_down, sc);
867 	callout_setfunc(&sc->sc_md6_tmo, carp_master_down, sc);
868 
869 	LIST_INIT(&sc->carp_mc_listhead);
870 	ifp = &sc->sc_if;
871 	ifp->if_softc = sc;
872 	snprintf(ifp->if_xname, sizeof ifp->if_xname, "%s%d", ifc->ifc_name,
873 	    unit);
874 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
875 	ifp->if_ioctl = carp_ioctl;
876 	ifp->if_start = carp_start;
877 	IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
878 	IFQ_SET_READY(&ifp->if_snd);
879 	if_initialize(ifp);
880 	ether_ifattach(ifp, NULL);
881 	/* Overwrite ethernet defaults */
882 	ifp->if_type = IFT_CARP;
883 	ifp->if_output = carp_output;
884 	ifp->if_link_state = LINK_STATE_DOWN;
885 	carp_set_enaddr(sc);
886 	if_register(ifp);
887 
888 	return (0);
889 }
890 
891 static int
892 carp_clone_destroy(struct ifnet *ifp)
893 {
894 	struct carp_softc *sc = ifp->if_softc;
895 
896 	carpdetach(ifp->if_softc);
897 	ether_ifdetach(ifp);
898 	if_detach(ifp);
899 	callout_destroy(&sc->sc_ad_tmo);
900 	callout_destroy(&sc->sc_md_tmo);
901 	callout_destroy(&sc->sc_md6_tmo);
902 	free(ifp->if_softc, M_DEVBUF);
903 
904 	return (0);
905 }
906 
907 static void
908 carpdetach(struct carp_softc *sc)
909 {
910 	struct ifnet *ifp;
911 	struct carp_if *cif;
912 	int s;
913 
914 	callout_stop(&sc->sc_ad_tmo);
915 	callout_stop(&sc->sc_md_tmo);
916 	callout_stop(&sc->sc_md6_tmo);
917 
918 	if (sc->sc_suppress)
919 		carp_suppress_preempt--;
920 	sc->sc_suppress = 0;
921 
922 	if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS)
923 		carp_suppress_preempt--;
924 	sc->sc_sendad_errors = 0;
925 
926 	carp_set_state(sc, INIT);
927 	sc->sc_if.if_flags &= ~IFF_UP;
928 	carp_setrun(sc, 0);
929 	carp_multicast_cleanup(sc);
930 
931 	KERNEL_LOCK(1, NULL);
932 	s = splnet();
933 	ifp = sc->sc_carpdev;
934 	if (ifp != NULL) {
935 		if_linkstate_change_disestablish(ifp,
936 		    sc->sc_linkstate_hook, NULL);
937 
938 		cif = (struct carp_if *)ifp->if_carp;
939 		TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
940 		if (!--cif->vhif_nvrs) {
941 			ifpromisc(ifp, 0);
942 			ifp->if_carp = NULL;
943 			free(cif, M_IFADDR);
944 		}
945 	}
946 	sc->sc_carpdev = NULL;
947 	splx(s);
948 	KERNEL_UNLOCK_ONE(NULL);
949 }
950 
951 /* Detach an interface from the carp. */
952 void
953 carp_ifdetach(struct ifnet *ifp)
954 {
955 	struct carp_softc *sc, *nextsc;
956 	struct carp_if *cif = (struct carp_if *)ifp->if_carp;
957 
958 	for (sc = TAILQ_FIRST(&cif->vhif_vrs); sc; sc = nextsc) {
959 		nextsc = TAILQ_NEXT(sc, sc_list);
960 		carpdetach(sc);
961 	}
962 }
963 
964 static void
965 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc,
966     struct carp_header *ch)
967 {
968 	if (sc->sc_init_counter) {
969 		/* this could also be seconds since unix epoch */
970 		sc->sc_counter = cprng_fast64();
971 	} else
972 		sc->sc_counter++;
973 
974 	ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
975 	ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
976 
977 	carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
978 }
979 
980 static void
981 carp_send_ad_all(void)
982 {
983 	struct ifnet *ifp;
984 	struct carp_if *cif;
985 	struct carp_softc *vh;
986 	int s;
987 	int bound = curlwp_bind();
988 
989 	s = pserialize_read_enter();
990 	IFNET_READER_FOREACH(ifp) {
991 		struct psref psref;
992 		if (ifp->if_carp == NULL || ifp->if_type == IFT_CARP)
993 			continue;
994 
995 		if_acquire(ifp, &psref);
996 		pserialize_read_exit(s);
997 
998 		cif = (struct carp_if *)ifp->if_carp;
999 		TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1000 			if ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) ==
1001 			    (IFF_UP|IFF_RUNNING) && vh->sc_state == MASTER)
1002 				carp_send_ad(vh);
1003 		}
1004 
1005 		s = pserialize_read_enter();
1006 		if_release(ifp, &psref);
1007 	}
1008 	pserialize_read_exit(s);
1009 	curlwp_bindx(bound);
1010 }
1011 
1012 
1013 static void
1014 carp_send_ad(void *v)
1015 {
1016 	struct carp_header ch;
1017 	struct timeval tv;
1018 	struct carp_softc *sc = v;
1019 	struct carp_header *ch_ptr;
1020 	struct mbuf *m;
1021 	int error, len, advbase, advskew, s;
1022 	struct sockaddr sa;
1023 
1024 	KERNEL_LOCK(1, NULL);
1025 	s = splsoftnet();
1026 
1027 	advbase = advskew = 0; /* Sssssh compiler */
1028 	if (sc->sc_carpdev == NULL) {
1029 		if_statinc(&sc->sc_if, if_oerrors);
1030 		goto retry_later;
1031 	}
1032 
1033 	/* bow out if we've gone to backup (the carp interface is going down) */
1034 	if (sc->sc_bow_out) {
1035 		sc->sc_bow_out = 0;
1036 		advbase = 255;
1037 		advskew = 255;
1038 	} else {
1039 		advbase = sc->sc_advbase;
1040 		if (!carp_suppress_preempt || sc->sc_advskew > 240)
1041 			advskew = sc->sc_advskew;
1042 		else
1043 			advskew = 240;
1044 		tv.tv_sec = advbase;
1045 		tv.tv_usec = advskew * 1000000 / 256;
1046 	}
1047 
1048 	ch.carp_version = CARP_VERSION;
1049 	ch.carp_type = CARP_ADVERTISEMENT;
1050 	ch.carp_vhid = sc->sc_vhid;
1051 	ch.carp_advbase = advbase;
1052 	ch.carp_advskew = advskew;
1053 	ch.carp_authlen = 7;	/* XXX DEFINE */
1054 	ch.carp_pad1 = 0;	/* must be zero */
1055 	ch.carp_cksum = 0;
1056 
1057 
1058 #ifdef INET
1059 	if (sc->sc_naddrs) {
1060 		struct ip *ip;
1061 		struct ifaddr *ifa;
1062 		int _s;
1063 
1064 		MGETHDR(m, M_DONTWAIT, MT_HEADER);
1065 		if (m == NULL) {
1066 			if_statinc(&sc->sc_if, if_oerrors);
1067 			CARP_STATINC(CARP_STAT_ONOMEM);
1068 			/* XXX maybe less ? */
1069 			goto retry_later;
1070 		}
1071 		MCLAIM(m, &carp_proto_mowner_tx);
1072 		len = sizeof(*ip) + sizeof(ch);
1073 		m->m_pkthdr.len = len;
1074 		m_reset_rcvif(m);
1075 		m->m_len = len;
1076 		m_align(m, m->m_len);
1077 		m->m_flags |= M_MCAST;
1078 		ip = mtod(m, struct ip *);
1079 		ip->ip_v = IPVERSION;
1080 		ip->ip_hl = sizeof(*ip) >> 2;
1081 		ip->ip_tos = IPTOS_LOWDELAY;
1082 		ip->ip_len = htons(len);
1083 		ip->ip_id = 0;	/* no need for id, we don't support fragments */
1084 		ip->ip_off = htons(IP_DF);
1085 		ip->ip_ttl = CARP_DFLTTL;
1086 		ip->ip_p = IPPROTO_CARP;
1087 		ip->ip_sum = 0;
1088 
1089 		memset(&sa, 0, sizeof(sa));
1090 		sa.sa_family = AF_INET;
1091 		_s = pserialize_read_enter();
1092 		ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
1093 		if (ifa == NULL)
1094 			ip->ip_src.s_addr = 0;
1095 		else
1096 			ip->ip_src.s_addr =
1097 			    ifatoia(ifa)->ia_addr.sin_addr.s_addr;
1098 		pserialize_read_exit(_s);
1099 		ip->ip_dst.s_addr = INADDR_CARP_GROUP;
1100 
1101 		ch_ptr = (struct carp_header *)(&ip[1]);
1102 		memcpy(ch_ptr, &ch, sizeof(ch));
1103 		carp_prepare_ad(m, sc, ch_ptr);
1104 
1105 		m->m_data += sizeof(*ip);
1106 		ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip));
1107 		m->m_data -= sizeof(*ip);
1108 
1109 		nanotime(&sc->sc_if.if_lastchange);
1110 		if_statadd2(&sc->sc_if, if_opackets, 1, if_obytes, len);
1111 		CARP_STATINC(CARP_STAT_OPACKETS);
1112 
1113 		error = ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_imo,
1114 		    NULL);
1115 		if (error) {
1116 			if (error == ENOBUFS)
1117 				CARP_STATINC(CARP_STAT_ONOMEM);
1118 			else
1119 				CARP_LOG(sc, ("ip_output failed: %d", error));
1120 			if_statinc(&sc->sc_if, if_oerrors);
1121 			if (sc->sc_sendad_errors < INT_MAX)
1122 				sc->sc_sendad_errors++;
1123 			if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
1124 				carp_suppress_preempt++;
1125 				if (carp_suppress_preempt == 1)
1126 					carp_send_ad_all();
1127 			}
1128 			sc->sc_sendad_success = 0;
1129 		} else {
1130 			if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
1131 				if (++sc->sc_sendad_success >=
1132 				    CARP_SENDAD_MIN_SUCCESS) {
1133 					carp_suppress_preempt--;
1134 					sc->sc_sendad_errors = 0;
1135 				}
1136 			} else
1137 				sc->sc_sendad_errors = 0;
1138 		}
1139 	}
1140 #endif /* INET */
1141 #ifdef INET6
1142 	if (sc->sc_naddrs6) {
1143 		struct ip6_hdr *ip6;
1144 		struct ifaddr *ifa;
1145 		int _s;
1146 
1147 		MGETHDR(m, M_DONTWAIT, MT_HEADER);
1148 		if (m == NULL) {
1149 			if_statinc(&sc->sc_if, if_oerrors);
1150 			CARP_STATINC(CARP_STAT_ONOMEM);
1151 			/* XXX maybe less ? */
1152 			goto retry_later;
1153 		}
1154 		MCLAIM(m, &carp_proto6_mowner_tx);
1155 		len = sizeof(*ip6) + sizeof(ch);
1156 		m->m_pkthdr.len = len;
1157 		m_reset_rcvif(m);
1158 		m->m_len = len;
1159 		m_align(m, m->m_len);
1160 		m->m_flags |= M_MCAST;
1161 		ip6 = mtod(m, struct ip6_hdr *);
1162 		memset(ip6, 0, sizeof(*ip6));
1163 		ip6->ip6_vfc |= IPV6_VERSION;
1164 		ip6->ip6_hlim = CARP_DFLTTL;
1165 		ip6->ip6_nxt = IPPROTO_CARP;
1166 
1167 		/* set the source address */
1168 		memset(&sa, 0, sizeof(sa));
1169 		sa.sa_family = AF_INET6;
1170 		_s = pserialize_read_enter();
1171 		ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
1172 		if (ifa == NULL)	/* This should never happen with IPv6 */
1173 			memset(&ip6->ip6_src, 0, sizeof(struct in6_addr));
1174 		else
1175 			bcopy(ifatoia6(ifa)->ia_addr.sin6_addr.s6_addr,
1176 			    &ip6->ip6_src, sizeof(struct in6_addr));
1177 		pserialize_read_exit(_s);
1178 		/* set the multicast destination */
1179 
1180 		ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
1181 		ip6->ip6_dst.s6_addr8[15] = 0x12;
1182 		if (in6_setscope(&ip6->ip6_dst, &sc->sc_if, NULL) != 0) {
1183 			if_statinc(&sc->sc_if, if_oerrors);
1184 			m_freem(m);
1185 			CARP_LOG(sc, ("in6_setscope failed"));
1186 			goto retry_later;
1187 		}
1188 
1189 		ch_ptr = (struct carp_header *)(&ip6[1]);
1190 		memcpy(ch_ptr, &ch, sizeof(ch));
1191 		carp_prepare_ad(m, sc, ch_ptr);
1192 
1193 		ch_ptr->carp_cksum = carp6_cksum(m, sizeof(*ip6),
1194 		    len - sizeof(*ip6));
1195 
1196 		nanotime(&sc->sc_if.if_lastchange);
1197 		if_statadd2(&sc->sc_if, if_opackets, 1, if_obytes, len);
1198 		CARP_STATINC(CARP_STAT_OPACKETS6);
1199 
1200 		error = ip6_output(m, NULL, NULL, 0, &sc->sc_im6o, NULL, NULL);
1201 		if (error) {
1202 			if (error == ENOBUFS)
1203 				CARP_STATINC(CARP_STAT_ONOMEM);
1204 			else
1205 				CARP_LOG(sc, ("ip6_output failed: %d", error));
1206 			if_statinc(&sc->sc_if, if_oerrors);
1207 			if (sc->sc_sendad_errors < INT_MAX)
1208 				sc->sc_sendad_errors++;
1209 			if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
1210 				carp_suppress_preempt++;
1211 				if (carp_suppress_preempt == 1)
1212 					carp_send_ad_all();
1213 			}
1214 			sc->sc_sendad_success = 0;
1215 		} else {
1216 			if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
1217 				if (++sc->sc_sendad_success >=
1218 				    CARP_SENDAD_MIN_SUCCESS) {
1219 					carp_suppress_preempt--;
1220 					sc->sc_sendad_errors = 0;
1221 				}
1222 			} else
1223 				sc->sc_sendad_errors = 0;
1224 		}
1225 	}
1226 #endif /* INET6 */
1227 
1228 retry_later:
1229 	splx(s);
1230 	KERNEL_UNLOCK_ONE(NULL);
1231 	if (advbase != 255 || advskew != 255)
1232 		callout_schedule(&sc->sc_ad_tmo, tvtohz(&tv));
1233 }
1234 
1235 /*
1236  * Broadcast a gratuitous ARP request containing
1237  * the virtual router MAC address for each IP address
1238  * associated with the virtual router.
1239  */
1240 static void
1241 carp_send_arp(struct carp_softc *sc)
1242 {
1243 	struct ifaddr *ifa;
1244 	int s, bound;
1245 
1246 	KERNEL_LOCK(1, NULL);
1247 	bound = curlwp_bind();
1248 	s = pserialize_read_enter();
1249 	IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
1250 		struct psref psref;
1251 
1252 		if (ifa->ifa_addr->sa_family != AF_INET)
1253 			continue;
1254 
1255 		ifa_acquire(ifa, &psref);
1256 		pserialize_read_exit(s);
1257 
1258 		arpannounce(sc->sc_carpdev, ifa, CLLADDR(sc->sc_if.if_sadl));
1259 
1260 		s = pserialize_read_enter();
1261 		ifa_release(ifa, &psref);
1262 	}
1263 	pserialize_read_exit(s);
1264 	curlwp_bindx(bound);
1265 	KERNEL_UNLOCK_ONE(NULL);
1266 }
1267 
1268 #ifdef INET6
1269 static void
1270 carp_send_na(struct carp_softc *sc)
1271 {
1272 	struct ifaddr *ifa;
1273 	struct in6_addr *in6;
1274 	static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
1275 	int s, bound;
1276 
1277 	KERNEL_LOCK(1, NULL);
1278 	bound = curlwp_bind();
1279 	s = pserialize_read_enter();
1280 	IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
1281 		struct psref psref;
1282 
1283 		if (ifa->ifa_addr->sa_family != AF_INET6)
1284 			continue;
1285 
1286 		ifa_acquire(ifa, &psref);
1287 		pserialize_read_exit(s);
1288 
1289 		in6 = &ifatoia6(ifa)->ia_addr.sin6_addr;
1290 		nd6_na_output(sc->sc_carpdev, &mcast, in6,
1291 		    ND_NA_FLAG_OVERRIDE, 1, NULL);
1292 
1293 		s = pserialize_read_enter();
1294 		ifa_release(ifa, &psref);
1295 	}
1296 	pserialize_read_exit(s);
1297 	curlwp_bindx(bound);
1298 	KERNEL_UNLOCK_ONE(NULL);
1299 }
1300 #endif /* INET6 */
1301 
1302 /*
1303  * Based on bridge_hash() in if_bridge.c
1304  */
1305 #define	mix(a,b,c) \
1306 	do {						\
1307 		a -= b; a -= c; a ^= (c >> 13);		\
1308 		b -= c; b -= a; b ^= (a << 8);		\
1309 		c -= a; c -= b; c ^= (b >> 13);		\
1310 		a -= b; a -= c; a ^= (c >> 12);		\
1311 		b -= c; b -= a; b ^= (a << 16);		\
1312 		c -= a; c -= b; c ^= (b >> 5);		\
1313 		a -= b; a -= c; a ^= (c >> 3);		\
1314 		b -= c; b -= a; b ^= (a << 10);		\
1315 		c -= a; c -= b; c ^= (b >> 15);		\
1316 	} while (0)
1317 
1318 static u_int32_t
1319 carp_hash(struct carp_softc *sc, u_char *src)
1320 {
1321 	u_int32_t a = 0x9e3779b9, b = sc->sc_hashkey[0], c = sc->sc_hashkey[1];
1322 
1323 	c += sc->sc_key[3] << 24;
1324 	c += sc->sc_key[2] << 16;
1325 	c += sc->sc_key[1] << 8;
1326 	c += sc->sc_key[0];
1327 	b += src[5] << 8;
1328 	b += src[4];
1329 	a += src[3] << 24;
1330 	a += src[2] << 16;
1331 	a += src[1] << 8;
1332 	a += src[0];
1333 
1334 	mix(a, b, c);
1335 	return (c);
1336 }
1337 
1338 static int
1339 carp_addrcount(struct carp_if *cif, struct in_ifaddr *ia, int type)
1340 {
1341 	struct carp_softc *vh;
1342 	struct ifaddr *ifa;
1343 	int count = 0;
1344 
1345 	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1346 		if ((type == CARP_COUNT_RUNNING &&
1347 		    (vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) ==
1348 		    (IFF_UP|IFF_RUNNING)) ||
1349 		    (type == CARP_COUNT_MASTER && vh->sc_state == MASTER)) {
1350 			int s = pserialize_read_enter();
1351 			IFADDR_READER_FOREACH(ifa, &vh->sc_if) {
1352 				if (ifa->ifa_addr->sa_family == AF_INET &&
1353 				    ia->ia_addr.sin_addr.s_addr ==
1354 				    ifatoia(ifa)->ia_addr.sin_addr.s_addr)
1355 					count++;
1356 			}
1357 			pserialize_read_exit(s);
1358 		}
1359 	}
1360 	return (count);
1361 }
1362 
1363 int
1364 carp_iamatch(struct in_ifaddr *ia, u_char *src,
1365     u_int32_t *count, u_int32_t index)
1366 {
1367 	struct carp_softc *sc = ia->ia_ifp->if_softc;
1368 
1369 	if (carp_opts[CARPCTL_ARPBALANCE]) {
1370 		/*
1371 		 * We use the source ip to decide which virtual host should
1372 		 * handle the request. If we're master of that virtual host,
1373 		 * then we respond, otherwise, just drop the arp packet on
1374 		 * the floor.
1375 		 */
1376 
1377 		/* Count the elegible carp interfaces with this address */
1378 		if (*count == 0)
1379 			*count = carp_addrcount(
1380 			    (struct carp_if *)ia->ia_ifp->if_carpdev->if_carp,
1381 			    ia, CARP_COUNT_RUNNING);
1382 
1383 		/* This should never happen, but... */
1384 		if (*count == 0)
1385 			return (0);
1386 
1387 		if (carp_hash(sc, src) % *count == index - 1 &&
1388 		    sc->sc_state == MASTER) {
1389 			return (1);
1390 		}
1391 	} else {
1392 		if (sc->sc_state == MASTER)
1393 			return (1);
1394 	}
1395 
1396 	return (0);
1397 }
1398 
1399 #ifdef INET6
1400 struct ifaddr *
1401 carp_iamatch6(void *v, struct in6_addr *taddr)
1402 {
1403 	struct carp_if *cif = v;
1404 	struct carp_softc *vh;
1405 	struct ifaddr *ifa;
1406 
1407 	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1408 		int s = pserialize_read_enter();
1409 		IFADDR_READER_FOREACH(ifa, &vh->sc_if) {
1410 			if (IN6_ARE_ADDR_EQUAL(taddr,
1411 			    &ifatoia6(ifa)->ia_addr.sin6_addr) &&
1412 			    ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) ==
1413 			    (IFF_UP|IFF_RUNNING)) && vh->sc_state == MASTER)
1414 				return (ifa);
1415 		}
1416 		pserialize_read_exit(s);
1417 	}
1418 
1419 	return (NULL);
1420 }
1421 #endif /* INET6 */
1422 
1423 struct ifnet *
1424 carp_ourether(void *v, struct ether_header *eh, u_char iftype, int src)
1425 {
1426 	struct carp_if *cif = (struct carp_if *)v;
1427 	struct carp_softc *vh;
1428 	u_int8_t *ena;
1429 
1430 	if (src)
1431 		ena = (u_int8_t *)&eh->ether_shost;
1432 	else
1433 		ena = (u_int8_t *)&eh->ether_dhost;
1434 
1435 	switch (iftype) {
1436 	case IFT_ETHER:
1437 	case IFT_FDDI:
1438 		if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
1439 			return (NULL);
1440 		break;
1441 	case IFT_ISO88025:
1442 		if (ena[0] != 3 || ena[1] || ena[4] || ena[5])
1443 			return (NULL);
1444 		break;
1445 	default:
1446 		return (NULL);
1447 		break;
1448 	}
1449 
1450 	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list)
1451 		if ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) ==
1452 		    (IFF_UP|IFF_RUNNING) && vh->sc_state == MASTER &&
1453 		    !memcmp(ena, CLLADDR(vh->sc_if.if_sadl),
1454 		    ETHER_ADDR_LEN)) {
1455 			return (&vh->sc_if);
1456 		    }
1457 
1458 	return (NULL);
1459 }
1460 
1461 int
1462 carp_input(struct mbuf *m, u_int8_t *shost, u_int8_t *dhost, u_int16_t etype)
1463 {
1464 	struct ether_header eh;
1465 	struct carp_if *cif = (struct carp_if *)m_get_rcvif_NOMPSAFE(m)->if_carp;
1466 	struct ifnet *ifp;
1467 
1468 	memcpy(&eh.ether_shost, shost, sizeof(eh.ether_shost));
1469 	memcpy(&eh.ether_dhost, dhost, sizeof(eh.ether_dhost));
1470 	eh.ether_type = etype;
1471 
1472 	if (m->m_flags & (M_BCAST|M_MCAST)) {
1473 		struct carp_softc *vh;
1474 		struct mbuf *m0;
1475 
1476 		/*
1477 		 * XXX Should really check the list of multicast addresses
1478 		 * for each CARP interface _before_ copying.
1479 		 */
1480 		TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1481 			m0 = m_copym(m, 0, M_COPYALL, M_DONTWAIT);
1482 			if (m0 == NULL)
1483 				continue;
1484 			m_set_rcvif(m0, &vh->sc_if);
1485 			ether_input(&vh->sc_if, m0);
1486 		}
1487 		return (1);
1488 	}
1489 
1490 	ifp = carp_ourether(cif, &eh, m_get_rcvif_NOMPSAFE(m)->if_type, 0);
1491 	if (ifp == NULL) {
1492 		return (1);
1493 	}
1494 
1495 	m_set_rcvif(m, ifp);
1496 
1497 	bpf_mtap(ifp, m, BPF_D_IN);
1498 	if_statinc(ifp, if_ipackets);
1499 	ether_input(ifp, m);
1500 	return (0);
1501 }
1502 
1503 static void
1504 carp_master_down(void *v)
1505 {
1506 	struct carp_softc *sc = v;
1507 
1508 	switch (sc->sc_state) {
1509 	case INIT:
1510 		printf("%s: master_down event in INIT state\n",
1511 		    sc->sc_if.if_xname);
1512 		break;
1513 	case MASTER:
1514 		break;
1515 	case BACKUP:
1516 		CARP_LOG(sc, ("INIT -> MASTER (preempting)"));
1517 		carp_set_state(sc, MASTER);
1518 		carp_send_ad(sc);
1519 		carp_send_arp(sc);
1520 #ifdef INET6
1521 		carp_send_na(sc);
1522 #endif /* INET6 */
1523 		carp_setrun(sc, 0);
1524 		carp_setroute(sc, RTM_ADD);
1525 		break;
1526 	}
1527 }
1528 
1529 /*
1530  * When in backup state, af indicates whether to reset the master down timer
1531  * for v4 or v6. If it's set to zero, reset the ones which are already pending.
1532  */
1533 static void
1534 carp_setrun(struct carp_softc *sc, sa_family_t af)
1535 {
1536 	struct timeval tv;
1537 
1538 	if (sc->sc_carpdev == NULL) {
1539 		sc->sc_if.if_flags &= ~IFF_RUNNING;
1540 		carp_set_state(sc, INIT);
1541 		return;
1542 	}
1543 
1544 	if (sc->sc_if.if_flags & IFF_UP && sc->sc_vhid > 0 &&
1545 	    (sc->sc_naddrs || sc->sc_naddrs6) && !sc->sc_suppress) {
1546 		sc->sc_if.if_flags |= IFF_RUNNING;
1547 	} else {
1548 		sc->sc_if.if_flags &= ~IFF_RUNNING;
1549 		carp_setroute(sc, RTM_DELETE);
1550 		return;
1551 	}
1552 
1553 	switch (sc->sc_state) {
1554 	case INIT:
1555 		carp_set_state(sc, BACKUP);
1556 		carp_setroute(sc, RTM_DELETE);
1557 		carp_setrun(sc, 0);
1558 		break;
1559 	case BACKUP:
1560 		callout_stop(&sc->sc_ad_tmo);
1561 		tv.tv_sec = 3 * sc->sc_advbase;
1562 		tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1563 		switch (af) {
1564 #ifdef INET
1565 		case AF_INET:
1566 			callout_schedule(&sc->sc_md_tmo, tvtohz(&tv));
1567 			break;
1568 #endif /* INET */
1569 #ifdef INET6
1570 		case AF_INET6:
1571 			callout_schedule(&sc->sc_md6_tmo, tvtohz(&tv));
1572 			break;
1573 #endif /* INET6 */
1574 		default:
1575 			if (sc->sc_naddrs)
1576 				callout_schedule(&sc->sc_md_tmo, tvtohz(&tv));
1577 #ifdef INET6
1578 			if (sc->sc_naddrs6)
1579 				callout_schedule(&sc->sc_md6_tmo, tvtohz(&tv));
1580 #endif /* INET6 */
1581 			break;
1582 		}
1583 		break;
1584 	case MASTER:
1585 		tv.tv_sec = sc->sc_advbase;
1586 		tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1587 		callout_schedule(&sc->sc_ad_tmo, tvtohz(&tv));
1588 		break;
1589 	}
1590 }
1591 
1592 static void
1593 carp_multicast_cleanup(struct carp_softc *sc)
1594 {
1595 	struct ip_moptions *imo = &sc->sc_imo;
1596 #ifdef INET6
1597 	struct ip6_moptions *im6o = &sc->sc_im6o;
1598 #endif
1599 	u_int16_t n = imo->imo_num_memberships;
1600 
1601 	/* Clean up our own multicast memberships */
1602 	while (n-- > 0) {
1603 		if (imo->imo_membership[n] != NULL) {
1604 			in_delmulti(imo->imo_membership[n]);
1605 			imo->imo_membership[n] = NULL;
1606 		}
1607 	}
1608 	imo->imo_num_memberships = 0;
1609 	imo->imo_multicast_if_index = 0;
1610 
1611 #ifdef INET6
1612 	while (!LIST_EMPTY(&im6o->im6o_memberships)) {
1613 		struct in6_multi_mship *imm =
1614 		    LIST_FIRST(&im6o->im6o_memberships);
1615 
1616 		LIST_REMOVE(imm, i6mm_chain);
1617 		in6_leavegroup(imm);
1618 	}
1619 	im6o->im6o_multicast_if_index = 0;
1620 #endif
1621 
1622 	/* And any other multicast memberships */
1623 	carp_ether_purgemulti(sc);
1624 }
1625 
1626 static int
1627 carp_set_ifp(struct carp_softc *sc, struct ifnet *ifp)
1628 {
1629 	struct carp_if *cif, *ncif = NULL;
1630 	struct carp_softc *vr, *after = NULL;
1631 	int myself = 0, error = 0;
1632 	int s;
1633 
1634 	if (ifp == sc->sc_carpdev)
1635 		return (0);
1636 
1637 	if (ifp != NULL) {
1638 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
1639 			return (EADDRNOTAVAIL);
1640 
1641 		if (ifp->if_type == IFT_CARP)
1642 			return (EINVAL);
1643 
1644 		if (ifp->if_carp == NULL) {
1645 			ncif = malloc(sizeof(*cif), M_IFADDR, M_WAITOK);
1646 			if ((error = ifpromisc(ifp, 1))) {
1647 				free(ncif, M_IFADDR);
1648 				return (error);
1649 			}
1650 
1651 			ncif->vhif_ifp = ifp;
1652 			TAILQ_INIT(&ncif->vhif_vrs);
1653 		} else {
1654 			cif = (struct carp_if *)ifp->if_carp;
1655 			TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
1656 				if (vr != sc && vr->sc_vhid == sc->sc_vhid)
1657 					return (EINVAL);
1658 		}
1659 
1660 		/* detach from old interface */
1661 		if (sc->sc_carpdev != NULL)
1662 			carpdetach(sc);
1663 
1664 		/* join multicast groups */
1665 		if (sc->sc_naddrs < 0 &&
1666 		    (error = carp_join_multicast(sc)) != 0) {
1667 			if (ncif != NULL)
1668 				free(ncif, M_IFADDR);
1669 			return (error);
1670 		}
1671 
1672 #ifdef INET6
1673 		if (sc->sc_naddrs6 < 0 &&
1674 		    (error = carp_join_multicast6(sc)) != 0) {
1675 			if (ncif != NULL)
1676 				free(ncif, M_IFADDR);
1677 			carp_multicast_cleanup(sc);
1678 			return (error);
1679 		}
1680 #endif
1681 
1682 		/* attach carp interface to physical interface */
1683 		if (ncif != NULL)
1684 			ifp->if_carp = (void *)ncif;
1685 		sc->sc_carpdev = ifp;
1686 		sc->sc_if.if_capabilities = ifp->if_capabilities &
1687 		             (IFCAP_TSOv4 | IFCAP_TSOv6 |
1688                              IFCAP_CSUM_IPv4_Tx|IFCAP_CSUM_IPv4_Rx|
1689                              IFCAP_CSUM_TCPv4_Tx|IFCAP_CSUM_TCPv4_Rx|
1690                              IFCAP_CSUM_UDPv4_Tx|IFCAP_CSUM_UDPv4_Rx|
1691                              IFCAP_CSUM_TCPv6_Tx|IFCAP_CSUM_TCPv6_Rx|
1692                              IFCAP_CSUM_UDPv6_Tx|IFCAP_CSUM_UDPv6_Rx);
1693 
1694 		cif = (struct carp_if *)ifp->if_carp;
1695 		TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) {
1696 			if (vr == sc)
1697 				myself = 1;
1698 			if (vr->sc_vhid < sc->sc_vhid)
1699 				after = vr;
1700 		}
1701 
1702 		if (!myself) {
1703 			/* We're trying to keep things in order */
1704 			if (after == NULL) {
1705 				TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list);
1706 			} else {
1707 				TAILQ_INSERT_AFTER(&cif->vhif_vrs, after,
1708 				    sc, sc_list);
1709 			}
1710 			cif->vhif_nvrs++;
1711 		}
1712 		if (sc->sc_naddrs || sc->sc_naddrs6)
1713 			sc->sc_if.if_flags |= IFF_UP;
1714 		carp_set_enaddr(sc);
1715 		sc->sc_linkstate_hook = if_linkstate_change_establish(ifp,
1716 		    carp_carpdev_state, (void *)ifp);
1717 		KERNEL_LOCK(1, NULL);
1718 		s = splnet();
1719 		carp_carpdev_state(ifp);
1720 		splx(s);
1721 		KERNEL_UNLOCK_ONE(NULL);
1722 	} else {
1723 		carpdetach(sc);
1724 		sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
1725 	}
1726 	return (0);
1727 }
1728 
1729 static void
1730 carp_set_enaddr(struct carp_softc *sc)
1731 {
1732 	struct ifnet *ifp = &sc->sc_if;
1733 	uint8_t enaddr[ETHER_ADDR_LEN];
1734 
1735 	if (sc->sc_vhid == -1) {
1736 		ifp->if_addrlen = 0;
1737 		if_alloc_sadl(ifp);
1738 		return;
1739 	}
1740 
1741 	if (sc->sc_carpdev && sc->sc_carpdev->if_type == IFT_ISO88025) {
1742 		enaddr[0] = 3;
1743 		enaddr[1] = 0;
1744 		enaddr[2] = 0x40 >> (sc->sc_vhid - 1);
1745 		enaddr[3] = 0x40000 >> (sc->sc_vhid - 1);
1746 		enaddr[4] = 0;
1747 		enaddr[5] = 0;
1748 	} else {
1749 		enaddr[0] = 0;
1750 		enaddr[1] = 0;
1751 		enaddr[2] = 0x5e;
1752 		enaddr[3] = 0;
1753 		enaddr[4] = 1;
1754 		enaddr[5] = sc->sc_vhid;
1755 	}
1756 
1757 	if_set_sadl(ifp, enaddr, sizeof(enaddr), false);
1758 }
1759 
1760 #if 0
1761 static void
1762 carp_addr_updated(void *v)
1763 {
1764 	struct carp_softc *sc = (struct carp_softc *) v;
1765 	struct ifaddr *ifa;
1766 	int new_naddrs = 0, new_naddrs6 = 0;
1767 
1768 	IFADDR_READER_FOREACH(ifa, &sc->sc_if) {
1769 		if (ifa->ifa_addr->sa_family == AF_INET)
1770 			new_naddrs++;
1771 		else if (ifa->ifa_addr->sa_family == AF_INET6)
1772 			new_naddrs6++;
1773 	}
1774 
1775 	/* Handle a callback after SIOCDIFADDR */
1776 	if (new_naddrs < sc->sc_naddrs || new_naddrs6 < sc->sc_naddrs6) {
1777 		struct in_addr mc_addr;
1778 
1779 		sc->sc_naddrs = new_naddrs;
1780 		sc->sc_naddrs6 = new_naddrs6;
1781 
1782 		/* Re-establish multicast membership removed by in_control */
1783 		mc_addr.s_addr = INADDR_CARP_GROUP;
1784 		if (!in_multi_group(mc_addr, &sc->sc_if, 0)) {
1785 			memset(&sc->sc_imo, 0, sizeof(sc->sc_imo));
1786 
1787 			if (sc->sc_carpdev != NULL && sc->sc_naddrs > 0)
1788 				carp_join_multicast(sc);
1789 		}
1790 
1791 		if (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) {
1792 			sc->sc_if.if_flags &= ~IFF_UP;
1793 			carp_set_state(sc, INIT);
1794 		} else
1795 			carp_hmac_prepare(sc);
1796 	}
1797 
1798 	carp_setrun(sc, 0);
1799 }
1800 #endif
1801 
1802 static int
1803 carp_set_addr(struct carp_softc *sc, struct sockaddr_in *sin)
1804 {
1805 	struct ifnet *ifp = sc->sc_carpdev;
1806 	struct in_ifaddr *ia, *ia_if;
1807 	int error = 0;
1808 	int s;
1809 
1810 	if (sin->sin_addr.s_addr == 0) {
1811 		if (!(sc->sc_if.if_flags & IFF_UP))
1812 			carp_set_state(sc, INIT);
1813 		if (sc->sc_naddrs)
1814 			sc->sc_if.if_flags |= IFF_UP;
1815 		carp_setrun(sc, 0);
1816 		return (0);
1817 	}
1818 
1819 	/* we have to do this by hand to ensure we don't match on ourselves */
1820 	ia_if = NULL;
1821 	s = pserialize_read_enter();
1822 	IN_ADDRLIST_READER_FOREACH(ia) {
1823 		/* and, yeah, we need a multicast-capable iface too */
1824 		if (ia->ia_ifp != &sc->sc_if &&
1825 		    ia->ia_ifp->if_type != IFT_CARP &&
1826 		    (ia->ia_ifp->if_flags & IFF_MULTICAST) &&
1827 		    (sin->sin_addr.s_addr & ia->ia_subnetmask) ==
1828 		    ia->ia_subnet) {
1829 			if (!ia_if)
1830 				ia_if = ia;
1831 		}
1832 	}
1833 
1834 	if (ia_if) {
1835 		ia = ia_if;
1836 		if (ifp) {
1837 			if (ifp != ia->ia_ifp)
1838 				return (EADDRNOTAVAIL);
1839 		} else {
1840 			/* FIXME NOMPSAFE */
1841 			ifp = ia->ia_ifp;
1842 		}
1843 	}
1844 	pserialize_read_exit(s);
1845 
1846 	if ((error = carp_set_ifp(sc, ifp)))
1847 		return (error);
1848 
1849 	if (sc->sc_carpdev == NULL)
1850 		return (EADDRNOTAVAIL);
1851 
1852 	if (sc->sc_naddrs == 0 && (error = carp_join_multicast(sc)) != 0)
1853 		return (error);
1854 
1855 	sc->sc_naddrs++;
1856 	if (sc->sc_carpdev != NULL)
1857 		sc->sc_if.if_flags |= IFF_UP;
1858 
1859 	carp_set_state(sc, INIT);
1860 	carp_setrun(sc, 0);
1861 
1862 	/*
1863 	 * Hook if_addrhooks so that we get a callback after in_ifinit has run,
1864 	 * to correct any inappropriate routes that it inserted.
1865 	 */
1866 	if (sc->ah_cookie == 0) {
1867 		/* XXX link address hook */
1868 	}
1869 
1870 	return (0);
1871 }
1872 
1873 static int
1874 carp_join_multicast(struct carp_softc *sc)
1875 {
1876 	struct ip_moptions *imo = &sc->sc_imo, tmpimo;
1877 	struct in_addr addr;
1878 
1879 	memset(&tmpimo, 0, sizeof(tmpimo));
1880 	addr.s_addr = INADDR_CARP_GROUP;
1881 	if ((tmpimo.imo_membership[0] =
1882 	    in_addmulti(&addr, &sc->sc_if)) == NULL) {
1883 		return (ENOBUFS);
1884 	}
1885 
1886 	imo->imo_membership[0] = tmpimo.imo_membership[0];
1887 	imo->imo_num_memberships = 1;
1888 	imo->imo_multicast_if_index = sc->sc_if.if_index;
1889 	imo->imo_multicast_ttl = CARP_DFLTTL;
1890 	imo->imo_multicast_loop = 0;
1891 	return (0);
1892 }
1893 
1894 
1895 #ifdef INET6
1896 static int
1897 carp_set_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6)
1898 {
1899 	struct ifnet *ifp = sc->sc_carpdev;
1900 	struct in6_ifaddr *ia, *ia_if;
1901 	int error = 0;
1902 	int s;
1903 
1904 	if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
1905 		if (!(sc->sc_if.if_flags & IFF_UP))
1906 			carp_set_state(sc, INIT);
1907 		if (sc->sc_naddrs6)
1908 			sc->sc_if.if_flags |= IFF_UP;
1909 		carp_setrun(sc, 0);
1910 		return (0);
1911 	}
1912 
1913 	/* we have to do this by hand to ensure we don't match on ourselves */
1914 	ia_if = NULL;
1915 	s = pserialize_read_enter();
1916 	IN6_ADDRLIST_READER_FOREACH(ia) {
1917 		int i;
1918 
1919 		for (i = 0; i < 4; i++) {
1920 			if ((sin6->sin6_addr.s6_addr32[i] &
1921 			    ia->ia_prefixmask.sin6_addr.s6_addr32[i]) !=
1922 			    (ia->ia_addr.sin6_addr.s6_addr32[i] &
1923 			    ia->ia_prefixmask.sin6_addr.s6_addr32[i]))
1924 				break;
1925 		}
1926 		/* and, yeah, we need a multicast-capable iface too */
1927 		if (ia->ia_ifp != &sc->sc_if &&
1928 		    ia->ia_ifp->if_type != IFT_CARP &&
1929 		    (ia->ia_ifp->if_flags & IFF_MULTICAST) &&
1930 		    (i == 4)) {
1931 			if (!ia_if)
1932 				ia_if = ia;
1933 		}
1934 	}
1935 	pserialize_read_exit(s);
1936 
1937 	if (ia_if) {
1938 		ia = ia_if;
1939 		if (sc->sc_carpdev) {
1940 			if (sc->sc_carpdev != ia->ia_ifp)
1941 				return (EADDRNOTAVAIL);
1942 		} else {
1943 			ifp = ia->ia_ifp;
1944 		}
1945 	}
1946 
1947 	if ((error = carp_set_ifp(sc, ifp)))
1948 		return (error);
1949 
1950 	if (sc->sc_carpdev == NULL)
1951 		return (EADDRNOTAVAIL);
1952 
1953 	if (sc->sc_naddrs6 == 0 && (error = carp_join_multicast6(sc)) != 0)
1954 		return (error);
1955 
1956 	sc->sc_naddrs6++;
1957 	if (sc->sc_carpdev != NULL)
1958 		sc->sc_if.if_flags |= IFF_UP;
1959 	carp_set_state(sc, INIT);
1960 	carp_setrun(sc, 0);
1961 
1962 	return (0);
1963 }
1964 
1965 static int
1966 carp_join_multicast6(struct carp_softc *sc)
1967 {
1968 	struct in6_multi_mship *imm, *imm2;
1969 	struct ip6_moptions *im6o = &sc->sc_im6o;
1970 	struct sockaddr_in6 addr6;
1971 	int error;
1972 
1973 	/* Join IPv6 CARP multicast group */
1974 	memset(&addr6, 0, sizeof(addr6));
1975 	addr6.sin6_family = AF_INET6;
1976 	addr6.sin6_len = sizeof(addr6);
1977 	addr6.sin6_addr.s6_addr16[0] = htons(0xff02);
1978 	addr6.sin6_addr.s6_addr16[1] = htons(sc->sc_if.if_index);
1979 	addr6.sin6_addr.s6_addr8[15] = 0x12;
1980 	if ((imm = in6_joingroup(&sc->sc_if,
1981 	    &addr6.sin6_addr, &error, 0)) == NULL) {
1982 		return (error);
1983 	}
1984 	/* join solicited multicast address */
1985 	memset(&addr6.sin6_addr, 0, sizeof(addr6.sin6_addr));
1986 	addr6.sin6_addr.s6_addr16[0] = htons(0xff02);
1987 	addr6.sin6_addr.s6_addr16[1] = htons(sc->sc_if.if_index);
1988 	addr6.sin6_addr.s6_addr32[1] = 0;
1989 	addr6.sin6_addr.s6_addr32[2] = htonl(1);
1990 	addr6.sin6_addr.s6_addr32[3] = 0;
1991 	addr6.sin6_addr.s6_addr8[12] = 0xff;
1992 	if ((imm2 = in6_joingroup(&sc->sc_if,
1993 	    &addr6.sin6_addr, &error, 0)) == NULL) {
1994 		in6_leavegroup(imm);
1995 		return (error);
1996 	}
1997 
1998 	/* apply v6 multicast membership */
1999 	im6o->im6o_multicast_if_index = sc->sc_if.if_index;
2000 	if (imm)
2001 		LIST_INSERT_HEAD(&im6o->im6o_memberships, imm,
2002 		    i6mm_chain);
2003 	if (imm2)
2004 		LIST_INSERT_HEAD(&im6o->im6o_memberships, imm2,
2005 		    i6mm_chain);
2006 
2007 	return (0);
2008 }
2009 
2010 #endif /* INET6 */
2011 
2012 static int
2013 carp_ioctl(struct ifnet *ifp, u_long cmd, void *data)
2014 {
2015 	struct lwp *l = curlwp;		/* XXX */
2016 	struct carp_softc *sc = ifp->if_softc, *vr;
2017 	struct carpreq carpr;
2018 	struct ifaddr *ifa;
2019 	struct ifreq *ifr;
2020 	struct ifnet *cdev = NULL;
2021 	int error = 0;
2022 
2023 	ifa = (struct ifaddr *)data;
2024 	ifr = (struct ifreq *)data;
2025 
2026 	switch (cmd) {
2027 	case SIOCINITIFADDR:
2028 		switch (ifa->ifa_addr->sa_family) {
2029 #ifdef INET
2030 		case AF_INET:
2031 			sc->sc_if.if_flags |= IFF_UP;
2032 			memcpy(ifa->ifa_dstaddr, ifa->ifa_addr,
2033 			    sizeof(struct sockaddr));
2034 			error = carp_set_addr(sc, satosin(ifa->ifa_addr));
2035 			break;
2036 #endif /* INET */
2037 #ifdef INET6
2038 		case AF_INET6:
2039 			sc->sc_if.if_flags|= IFF_UP;
2040 			error = carp_set_addr6(sc, satosin6(ifa->ifa_addr));
2041 			break;
2042 #endif /* INET6 */
2043 		default:
2044 			error = EAFNOSUPPORT;
2045 			break;
2046 		}
2047 		break;
2048 
2049 	case SIOCSIFFLAGS:
2050 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
2051 			break;
2052 		if (sc->sc_state != INIT && !(ifr->ifr_flags & IFF_UP)) {
2053 			callout_stop(&sc->sc_ad_tmo);
2054 			callout_stop(&sc->sc_md_tmo);
2055 			callout_stop(&sc->sc_md6_tmo);
2056 			if (sc->sc_state == MASTER) {
2057 				/* we need the interface up to bow out */
2058 				sc->sc_if.if_flags |= IFF_UP;
2059 				sc->sc_bow_out = 1;
2060 				carp_send_ad(sc);
2061 			}
2062 			sc->sc_if.if_flags &= ~IFF_UP;
2063 			carp_set_state(sc, INIT);
2064 			carp_setrun(sc, 0);
2065 		} else if (sc->sc_state == INIT && (ifr->ifr_flags & IFF_UP)) {
2066 			sc->sc_if.if_flags |= IFF_UP;
2067 			carp_setrun(sc, 0);
2068 		}
2069 		carp_update_link_state(sc);
2070 		break;
2071 
2072 	case SIOCSVH:
2073 		if (l == NULL)
2074 			break;
2075 		if ((error = kauth_authorize_network(l->l_cred,
2076 		    KAUTH_NETWORK_INTERFACE,
2077 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
2078 		    NULL)) != 0)
2079 			break;
2080 		if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr)))
2081 			break;
2082 		error = 1;
2083 		if (carpr.carpr_carpdev[0] != '\0' &&
2084 		    (cdev = ifunit(carpr.carpr_carpdev)) == NULL)
2085 			return (EINVAL);
2086 		if ((error = carp_set_ifp(sc, cdev)))
2087 			return (error);
2088 		if (sc->sc_state != INIT && carpr.carpr_state != sc->sc_state) {
2089 			switch (carpr.carpr_state) {
2090 			case BACKUP:
2091 				callout_stop(&sc->sc_ad_tmo);
2092 				carp_set_state(sc, BACKUP);
2093 				carp_setrun(sc, 0);
2094 				carp_setroute(sc, RTM_DELETE);
2095 				break;
2096 			case MASTER:
2097 				carp_master_down(sc);
2098 				break;
2099 			default:
2100 				break;
2101 			}
2102 		}
2103 		if (carpr.carpr_vhid > 0) {
2104 			if (carpr.carpr_vhid > 255) {
2105 				error = EINVAL;
2106 				break;
2107 			}
2108 			if (sc->sc_carpdev) {
2109 				struct carp_if *cif;
2110 				cif = (struct carp_if *)sc->sc_carpdev->if_carp;
2111 				TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
2112 					if (vr != sc &&
2113 					    vr->sc_vhid == carpr.carpr_vhid)
2114 						return (EINVAL);
2115 			}
2116 			sc->sc_vhid = carpr.carpr_vhid;
2117 			carp_set_enaddr(sc);
2118 			carp_set_state(sc, INIT);
2119 			error--;
2120 		}
2121 		if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) {
2122 			if (carpr.carpr_advskew > 254) {
2123 				error = EINVAL;
2124 				break;
2125 			}
2126 			if (carpr.carpr_advbase > 255) {
2127 				error = EINVAL;
2128 				break;
2129 			}
2130 			sc->sc_advbase = carpr.carpr_advbase;
2131 			sc->sc_advskew = carpr.carpr_advskew;
2132 			error--;
2133 		}
2134 		memcpy(sc->sc_key, carpr.carpr_key, sizeof(sc->sc_key));
2135 		if (error > 0)
2136 			error = EINVAL;
2137 		else {
2138 			error = 0;
2139 			carp_setrun(sc, 0);
2140 		}
2141 		break;
2142 
2143 	case SIOCGVH:
2144 		memset(&carpr, 0, sizeof(carpr));
2145 		if (sc->sc_carpdev != NULL)
2146 			strlcpy(carpr.carpr_carpdev, sc->sc_carpdev->if_xname,
2147 			    IFNAMSIZ);
2148 		carpr.carpr_state = sc->sc_state;
2149 		carpr.carpr_vhid = sc->sc_vhid;
2150 		carpr.carpr_advbase = sc->sc_advbase;
2151 		carpr.carpr_advskew = sc->sc_advskew;
2152 
2153 		if ((l != NULL) && (error = kauth_authorize_network(l->l_cred,
2154 		    KAUTH_NETWORK_INTERFACE,
2155 		    KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd,
2156 		    NULL)) == 0)
2157 			memcpy(carpr.carpr_key, sc->sc_key,
2158 			    sizeof(carpr.carpr_key));
2159 		error = copyout(&carpr, ifr->ifr_data, sizeof(carpr));
2160 		break;
2161 
2162 	case SIOCADDMULTI:
2163 		error = carp_ether_addmulti(sc, ifr);
2164 		break;
2165 
2166 	case SIOCDELMULTI:
2167 		error = carp_ether_delmulti(sc, ifr);
2168 		break;
2169 
2170 	case SIOCSIFCAP:
2171 		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
2172 			error = 0;
2173 		break;
2174 
2175 	default:
2176 		error = ether_ioctl(ifp, cmd, data);
2177 	}
2178 
2179 	carp_hmac_prepare(sc);
2180 	return (error);
2181 }
2182 
2183 
2184 /*
2185  * Start output on carp interface. This function should never be called.
2186  */
2187 static void
2188 carp_start(struct ifnet *ifp)
2189 {
2190 #ifdef DEBUG
2191 	printf("%s: start called\n", ifp->if_xname);
2192 #endif
2193 }
2194 
2195 int
2196 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa,
2197     const struct rtentry *rt)
2198 {
2199 	struct carp_softc *sc = ((struct carp_softc *)ifp->if_softc);
2200 	KASSERT(KERNEL_LOCKED_P());
2201 
2202 	if (sc->sc_carpdev != NULL && sc->sc_state == MASTER) {
2203 		return if_output_lock(sc->sc_carpdev, ifp, m, sa, rt);
2204 	} else {
2205 		m_freem(m);
2206 		return (ENETUNREACH);
2207 	}
2208 }
2209 
2210 static void
2211 carp_set_state(struct carp_softc *sc, int state)
2212 {
2213 	static const char *carp_states[] = { CARP_STATES };
2214 
2215 	if (sc->sc_state == state)
2216 		return;
2217 
2218 	CARP_LOG(sc, ("state transition from: %s -> to: %s", carp_states[sc->sc_state], carp_states[state]));
2219 
2220 	sc->sc_state = state;
2221 	carp_update_link_state(sc);
2222 }
2223 
2224 static void
2225 carp_update_link_state(struct carp_softc *sc)
2226 {
2227 	int link_state;
2228 
2229 	switch (sc->sc_state) {
2230 	case BACKUP:
2231 		link_state = LINK_STATE_DOWN;
2232 		break;
2233 	case MASTER:
2234 		link_state = LINK_STATE_UP;
2235 		break;
2236 	default:
2237 		/* Not useable, so down makes perfect sense. */
2238 		link_state = LINK_STATE_DOWN;
2239 		break;
2240 	}
2241 	if_link_state_change(&sc->sc_if, link_state);
2242 }
2243 
2244 void
2245 carp_carpdev_state(void *v)
2246 {
2247 	struct carp_if *cif;
2248 	struct carp_softc *sc;
2249 	struct ifnet *ifp = v;
2250 
2251 	if (ifp->if_type == IFT_CARP)
2252 		return;
2253 
2254 	cif = (struct carp_if *)ifp->if_carp;
2255 
2256 	TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) {
2257 		int suppressed = sc->sc_suppress;
2258 
2259 		if (sc->sc_carpdev->if_link_state == LINK_STATE_DOWN ||
2260 		    !(sc->sc_carpdev->if_flags & IFF_UP)) {
2261 			sc->sc_if.if_flags &= ~IFF_RUNNING;
2262 			callout_stop(&sc->sc_ad_tmo);
2263 			callout_stop(&sc->sc_md_tmo);
2264 			callout_stop(&sc->sc_md6_tmo);
2265 			carp_set_state(sc, INIT);
2266 			sc->sc_suppress = 1;
2267 			carp_setrun(sc, 0);
2268 			if (!suppressed) {
2269 				carp_suppress_preempt++;
2270 				if (carp_suppress_preempt == 1)
2271 					carp_send_ad_all();
2272 			}
2273 		} else {
2274 			carp_set_state(sc, INIT);
2275 			sc->sc_suppress = 0;
2276 			carp_setrun(sc, 0);
2277 			if (suppressed)
2278 				carp_suppress_preempt--;
2279 		}
2280 	}
2281 }
2282 
2283 static int
2284 carp_ether_addmulti(struct carp_softc *sc, struct ifreq *ifr)
2285 {
2286 	const struct sockaddr *sa = ifreq_getaddr(SIOCADDMULTI, ifr);
2287 	struct ifnet *ifp;
2288 	struct carp_mc_entry *mc;
2289 	u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
2290 	int error;
2291 
2292 	ifp = sc->sc_carpdev;
2293 	if (ifp == NULL)
2294 		return (EINVAL);
2295 
2296 	error = ether_addmulti(sa, &sc->sc_ac);
2297 	if (error != ENETRESET)
2298 		return (error);
2299 
2300 	/*
2301 	 * This is new multicast address.  We have to tell parent
2302 	 * about it.  Also, remember this multicast address so that
2303 	 * we can delete them on unconfigure.
2304 	 */
2305 	mc = malloc(sizeof(struct carp_mc_entry), M_DEVBUF, M_NOWAIT);
2306 	if (mc == NULL) {
2307 		error = ENOMEM;
2308 		goto alloc_failed;
2309 	}
2310 
2311 	/*
2312 	 * As ether_addmulti() returns ENETRESET, following two
2313 	 * statement shouldn't fail.
2314 	 */
2315 	(void)ether_multiaddr(sa, addrlo, addrhi);
2316 
2317 	ETHER_LOCK(&sc->sc_ac);
2318 	mc->mc_enm = ether_lookup_multi(addrlo, addrhi, &sc->sc_ac);
2319 	ETHER_UNLOCK(&sc->sc_ac);
2320 
2321 	memcpy(&mc->mc_addr, sa, sa->sa_len);
2322 	LIST_INSERT_HEAD(&sc->carp_mc_listhead, mc, mc_entries);
2323 
2324 	error = if_mcast_op(ifp, SIOCADDMULTI, sa);
2325 	if (error != 0)
2326 		goto ioctl_failed;
2327 
2328 	return (error);
2329 
2330  ioctl_failed:
2331 	LIST_REMOVE(mc, mc_entries);
2332 	free(mc, M_DEVBUF);
2333  alloc_failed:
2334 	(void)ether_delmulti(sa, &sc->sc_ac);
2335 
2336 	return (error);
2337 }
2338 
2339 static int
2340 carp_ether_delmulti(struct carp_softc *sc, struct ifreq *ifr)
2341 {
2342 	const struct sockaddr *sa = ifreq_getaddr(SIOCDELMULTI, ifr);
2343 	struct ifnet *ifp;
2344 	struct ether_multi *enm;
2345 	struct carp_mc_entry *mc;
2346 	u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN];
2347 	int error;
2348 
2349 	ifp = sc->sc_carpdev;
2350 	if (ifp == NULL)
2351 		return (EINVAL);
2352 
2353 	/*
2354 	 * Find a key to lookup carp_mc_entry.  We have to do this
2355 	 * before calling ether_delmulti for obvious reason.
2356 	 */
2357 	if ((error = ether_multiaddr(sa, addrlo, addrhi)) != 0)
2358 		return (error);
2359 
2360 	ETHER_LOCK(&sc->sc_ac);
2361 	enm = ether_lookup_multi(addrlo, addrhi, &sc->sc_ac);
2362 	ETHER_UNLOCK(&sc->sc_ac);
2363 	if (enm == NULL)
2364 		return (EINVAL);
2365 
2366 	LIST_FOREACH(mc, &sc->carp_mc_listhead, mc_entries)
2367 		if (mc->mc_enm == enm)
2368 			break;
2369 
2370 	/* We won't delete entries we didn't add */
2371 	if (mc == NULL)
2372 		return (EINVAL);
2373 
2374 	error = ether_delmulti(sa, &sc->sc_ac);
2375 	if (error != ENETRESET)
2376 		return (error);
2377 
2378 	/* We no longer use this multicast address.  Tell parent so. */
2379 	error = if_mcast_op(ifp, SIOCDELMULTI, sa);
2380 	if (error == 0) {
2381 		/* And forget about this address. */
2382 		LIST_REMOVE(mc, mc_entries);
2383 		free(mc, M_DEVBUF);
2384 	} else
2385 		(void)ether_addmulti(sa, &sc->sc_ac);
2386 	return (error);
2387 }
2388 
2389 /*
2390  * Delete any multicast address we have asked to add from parent
2391  * interface.  Called when the carp is being unconfigured.
2392  */
2393 static void
2394 carp_ether_purgemulti(struct carp_softc *sc)
2395 {
2396 	struct ifnet *ifp = sc->sc_carpdev;		/* Parent. */
2397 	struct carp_mc_entry *mc;
2398 
2399 	if (ifp == NULL)
2400 		return;
2401 
2402 	while ((mc = LIST_FIRST(&sc->carp_mc_listhead)) != NULL) {
2403 		(void)if_mcast_op(ifp, SIOCDELMULTI, sstosa(&mc->mc_addr));
2404 		LIST_REMOVE(mc, mc_entries);
2405 		free(mc, M_DEVBUF);
2406 	}
2407 }
2408 
2409 static int
2410 sysctl_net_inet_carp_stats(SYSCTLFN_ARGS)
2411 {
2412 
2413 	return (NETSTAT_SYSCTL(carpstat_percpu, CARP_NSTATS));
2414 }
2415 
2416 void
2417 carp_init(void)
2418 {
2419 
2420 	sysctl_net_inet_carp_setup(NULL);
2421 #ifdef MBUFTRACE
2422 	MOWNER_ATTACH(&carp_proto_mowner_rx);
2423 	MOWNER_ATTACH(&carp_proto_mowner_tx);
2424 	MOWNER_ATTACH(&carp_proto6_mowner_rx);
2425 	MOWNER_ATTACH(&carp_proto6_mowner_tx);
2426 #endif
2427 
2428 	carp_wqinput = wqinput_create("carp", _carp_proto_input);
2429 #ifdef INET6
2430 	carp6_wqinput = wqinput_create("carp6", _carp6_proto_input);
2431 #endif
2432 }
2433 
2434 static void
2435 sysctl_net_inet_carp_setup(struct sysctllog **clog)
2436 {
2437 
2438 	sysctl_createv(clog, 0, NULL, NULL,
2439 		       CTLFLAG_PERMANENT,
2440 		       CTLTYPE_NODE, "inet", NULL,
2441 		       NULL, 0, NULL, 0,
2442 		       CTL_NET, PF_INET, CTL_EOL);
2443 	sysctl_createv(clog, 0, NULL, NULL,
2444 		       CTLFLAG_PERMANENT,
2445 		       CTLTYPE_NODE, "carp",
2446 		       SYSCTL_DESCR("CARP related settings"),
2447 		       NULL, 0, NULL, 0,
2448 		       CTL_NET, PF_INET, IPPROTO_CARP, CTL_EOL);
2449 
2450 	sysctl_createv(clog, 0, NULL, NULL,
2451 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2452 		       CTLTYPE_INT, "preempt",
2453 		       SYSCTL_DESCR("Enable CARP Preempt"),
2454 		       NULL, 0, &carp_opts[CARPCTL_PREEMPT], 0,
2455 		       CTL_NET, PF_INET, IPPROTO_CARP,
2456 		       CTL_CREATE, CTL_EOL);
2457 	sysctl_createv(clog, 0, NULL, NULL,
2458 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2459 		       CTLTYPE_INT, "arpbalance",
2460 		       SYSCTL_DESCR("Enable ARP balancing"),
2461 		       NULL, 0, &carp_opts[CARPCTL_ARPBALANCE], 0,
2462 		       CTL_NET, PF_INET, IPPROTO_CARP,
2463 		       CTL_CREATE, CTL_EOL);
2464 	sysctl_createv(clog, 0, NULL, NULL,
2465 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2466 		       CTLTYPE_INT, "allow",
2467 		       SYSCTL_DESCR("Enable CARP"),
2468 		       NULL, 0, &carp_opts[CARPCTL_ALLOW], 0,
2469 		       CTL_NET, PF_INET, IPPROTO_CARP,
2470 		       CTL_CREATE, CTL_EOL);
2471 	sysctl_createv(clog, 0, NULL, NULL,
2472 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2473 		       CTLTYPE_INT, "log",
2474 		       SYSCTL_DESCR("CARP logging"),
2475 		       NULL, 0, &carp_opts[CARPCTL_LOG], 0,
2476 		       CTL_NET, PF_INET, IPPROTO_CARP,
2477 		       CTL_CREATE, CTL_EOL);
2478 	sysctl_createv(clog, 0, NULL, NULL,
2479 		       CTLFLAG_PERMANENT,
2480 		       CTLTYPE_STRUCT, "stats",
2481 		       SYSCTL_DESCR("CARP statistics"),
2482 		       sysctl_net_inet_carp_stats, 0, NULL, 0,
2483 		       CTL_NET, PF_INET, IPPROTO_CARP, CARPCTL_STATS,
2484 		       CTL_EOL);
2485 }
2486