ip_carp.c revision 179490
1/*
2 * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
3 * Copyright (c) 2003 Ryan McBride. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
18 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
20 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
24 * THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/netinet/ip_carp.c 179490 2008-06-02 18:58:07Z mlaier $");
29
30#include "opt_carp.h"
31#include "opt_bpf.h"
32#include "opt_inet.h"
33#include "opt_inet6.h"
34
35#include <sys/types.h>
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/conf.h>
39#include <sys/kernel.h>
40#include <sys/limits.h>
41#include <sys/malloc.h>
42#include <sys/mbuf.h>
43#include <sys/module.h>
44#include <sys/time.h>
45#include <sys/priv.h>
46#include <sys/proc.h>
47#include <sys/sysctl.h>
48#include <sys/syslog.h>
49#include <sys/signalvar.h>
50#include <sys/filio.h>
51#include <sys/sockio.h>
52
53#include <sys/socket.h>
54#include <sys/vnode.h>
55
56#include <machine/stdarg.h>
57
58#include <net/bpf.h>
59#include <net/ethernet.h>
60#include <net/fddi.h>
61#include <net/iso88025.h>
62#include <net/if.h>
63#include <net/if_clone.h>
64#include <net/if_dl.h>
65#include <net/if_types.h>
66#include <net/route.h>
67
68#ifdef INET
69#include <netinet/in.h>
70#include <netinet/in_var.h>
71#include <netinet/in_systm.h>
72#include <netinet/ip.h>
73#include <netinet/ip_var.h>
74#include <netinet/if_ether.h>
75#include <machine/in_cksum.h>
76#endif
77
78#ifdef INET6
79#include <netinet/icmp6.h>
80#include <netinet/ip6.h>
81#include <netinet6/ip6_var.h>
82#include <netinet6/scope6_var.h>
83#include <netinet6/nd6.h>
84#endif
85
86#include <crypto/sha1.h>
87#include <netinet/ip_carp.h>
88
89#define	CARP_IFNAME	"carp"
90static MALLOC_DEFINE(M_CARP, "CARP", "CARP interfaces");
91SYSCTL_DECL(_net_inet_carp);
92
93struct carp_softc {
94	struct ifnet	 	*sc_ifp;	/* Interface clue */
95	struct ifnet		*sc_carpdev;	/* Pointer to parent interface */
96	struct in_ifaddr 	*sc_ia;		/* primary iface address */
97	struct ip_moptions 	 sc_imo;
98#ifdef INET6
99	struct in6_ifaddr 	*sc_ia6;	/* primary iface address v6 */
100	struct ip6_moptions 	 sc_im6o;
101#endif /* INET6 */
102	TAILQ_ENTRY(carp_softc)	 sc_list;
103
104	enum { INIT = 0, BACKUP, MASTER }	sc_state;
105
106	int			 sc_flags_backup;
107	int			 sc_suppress;
108
109	int			 sc_sendad_errors;
110#define	CARP_SENDAD_MAX_ERRORS	3
111	int			 sc_sendad_success;
112#define	CARP_SENDAD_MIN_SUCCESS 3
113
114	int			 sc_vhid;
115	int			 sc_advskew;
116	int			 sc_naddrs;
117	int			 sc_naddrs6;
118	int			 sc_advbase;	/* seconds */
119	int			 sc_init_counter;
120	u_int64_t		 sc_counter;
121
122	/* authentication */
123#define CARP_HMAC_PAD	64
124	unsigned char sc_key[CARP_KEY_LEN];
125	unsigned char sc_pad[CARP_HMAC_PAD];
126	SHA1_CTX sc_sha1;
127
128	struct callout		 sc_ad_tmo;	/* advertisement timeout */
129	struct callout		 sc_md_tmo;	/* master down timeout */
130	struct callout 		 sc_md6_tmo;	/* master down timeout */
131
132	LIST_ENTRY(carp_softc)	 sc_next;	/* Interface clue */
133};
134#define	SC2IFP(sc)	((sc)->sc_ifp)
135
136int carp_suppress_preempt = 0;
137int carp_opts[CARPCTL_MAXID] = { 0, 1, 0, 1, 0, 0 };	/* XXX for now */
138SYSCTL_INT(_net_inet_carp, CARPCTL_ALLOW, allow, CTLFLAG_RW,
139    &carp_opts[CARPCTL_ALLOW], 0, "Accept incoming CARP packets");
140SYSCTL_INT(_net_inet_carp, CARPCTL_PREEMPT, preempt, CTLFLAG_RW,
141    &carp_opts[CARPCTL_PREEMPT], 0, "high-priority backup preemption mode");
142SYSCTL_INT(_net_inet_carp, CARPCTL_LOG, log, CTLFLAG_RW,
143    &carp_opts[CARPCTL_LOG], 0, "log bad carp packets");
144SYSCTL_INT(_net_inet_carp, CARPCTL_ARPBALANCE, arpbalance, CTLFLAG_RW,
145    &carp_opts[CARPCTL_ARPBALANCE], 0, "balance arp responses");
146SYSCTL_INT(_net_inet_carp, OID_AUTO, suppress_preempt, CTLFLAG_RD,
147    &carp_suppress_preempt, 0, "Preemption is suppressed");
148
149struct carpstats carpstats;
150SYSCTL_STRUCT(_net_inet_carp, CARPCTL_STATS, stats, CTLFLAG_RW,
151    &carpstats, carpstats,
152    "CARP statistics (struct carpstats, netinet/ip_carp.h)");
153
154struct carp_if {
155	TAILQ_HEAD(, carp_softc) vhif_vrs;
156	int vhif_nvrs;
157
158	struct ifnet 	*vhif_ifp;
159	struct mtx	 vhif_mtx;
160};
161
162/* Get carp_if from softc. Valid after carp_set_addr{,6}. */
163#define	SC2CIF(sc)		((struct carp_if *)(sc)->sc_carpdev->if_carp)
164
165/* lock per carp_if queue */
166#define	CARP_LOCK_INIT(cif)	mtx_init(&(cif)->vhif_mtx, "carp_if", 	\
167	NULL, MTX_DEF)
168#define	CARP_LOCK_DESTROY(cif)	mtx_destroy(&(cif)->vhif_mtx)
169#define	CARP_LOCK_ASSERT(cif)	mtx_assert(&(cif)->vhif_mtx, MA_OWNED)
170#define	CARP_LOCK(cif)		mtx_lock(&(cif)->vhif_mtx)
171#define	CARP_UNLOCK(cif)	mtx_unlock(&(cif)->vhif_mtx)
172
173#define	CARP_SCLOCK(sc)		mtx_lock(&SC2CIF(sc)->vhif_mtx)
174#define	CARP_SCUNLOCK(sc)	mtx_unlock(&SC2CIF(sc)->vhif_mtx)
175#define	CARP_SCLOCK_ASSERT(sc)	mtx_assert(&SC2CIF(sc)->vhif_mtx, MA_OWNED)
176
177#define	CARP_LOG(...)	do {				\
178	if (carp_opts[CARPCTL_LOG] > 0)			\
179		log(LOG_INFO, __VA_ARGS__);		\
180} while (0)
181
182#define	CARP_DEBUG(...)	do {				\
183	if (carp_opts[CARPCTL_LOG] > 1)			\
184		log(LOG_DEBUG, __VA_ARGS__);		\
185} while (0)
186
187static void	carp_hmac_prepare(struct carp_softc *);
188static void	carp_hmac_generate(struct carp_softc *, u_int32_t *,
189		    unsigned char *);
190static int	carp_hmac_verify(struct carp_softc *, u_int32_t *,
191		    unsigned char *);
192static void	carp_setroute(struct carp_softc *, int);
193static void	carp_input_c(struct mbuf *, struct carp_header *, sa_family_t);
194static int 	carp_clone_create(struct if_clone *, int, caddr_t);
195static void 	carp_clone_destroy(struct ifnet *);
196static void	carpdetach(struct carp_softc *, int);
197static int	carp_prepare_ad(struct mbuf *, struct carp_softc *,
198		    struct carp_header *);
199static void	carp_send_ad_all(void);
200static void	carp_send_ad(void *);
201static void	carp_send_ad_locked(struct carp_softc *);
202static void	carp_send_arp(struct carp_softc *);
203static void	carp_master_down(void *);
204static void	carp_master_down_locked(struct carp_softc *);
205static int	carp_ioctl(struct ifnet *, u_long, caddr_t);
206static int	carp_looutput(struct ifnet *, struct mbuf *, struct sockaddr *,
207		    struct rtentry *);
208static void	carp_start(struct ifnet *);
209static void	carp_setrun(struct carp_softc *, sa_family_t);
210static void	carp_set_state(struct carp_softc *, int);
211static int	carp_addrcount(struct carp_if *, struct in_ifaddr *, int);
212enum	{ CARP_COUNT_MASTER, CARP_COUNT_RUNNING };
213
214static void	carp_multicast_cleanup(struct carp_softc *);
215static int	carp_set_addr(struct carp_softc *, struct sockaddr_in *);
216static int	carp_del_addr(struct carp_softc *, struct sockaddr_in *);
217static void	carp_carpdev_state_locked(struct carp_if *);
218static void	carp_sc_state_locked(struct carp_softc *);
219#ifdef INET6
220static void	carp_send_na(struct carp_softc *);
221static int	carp_set_addr6(struct carp_softc *, struct sockaddr_in6 *);
222static int	carp_del_addr6(struct carp_softc *, struct sockaddr_in6 *);
223static void	carp_multicast6_cleanup(struct carp_softc *);
224#endif
225
226static LIST_HEAD(, carp_softc) carpif_list;
227static struct mtx carp_mtx;
228IFC_SIMPLE_DECLARE(carp, 0);
229
230static eventhandler_tag if_detach_event_tag;
231
232static __inline u_int16_t
233carp_cksum(struct mbuf *m, int len)
234{
235	return (in_cksum(m, len));
236}
237
238static void
239carp_hmac_prepare(struct carp_softc *sc)
240{
241	u_int8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
242	u_int8_t vhid = sc->sc_vhid & 0xff;
243	struct ifaddr *ifa;
244	int i, found;
245#ifdef INET
246	struct in_addr last, cur, in;
247#endif
248#ifdef INET6
249	struct in6_addr last6, cur6, in6;
250#endif
251
252	if (sc->sc_carpdev)
253		CARP_SCLOCK(sc);
254
255	/* XXX: possible race here */
256
257	/* compute ipad from key */
258	bzero(sc->sc_pad, sizeof(sc->sc_pad));
259	bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key));
260	for (i = 0; i < sizeof(sc->sc_pad); i++)
261		sc->sc_pad[i] ^= 0x36;
262
263	/* precompute first part of inner hash */
264	SHA1Init(&sc->sc_sha1);
265	SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
266	SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version));
267	SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
268	SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
269#ifdef INET
270	cur.s_addr = 0;
271	do {
272		found = 0;
273		last = cur;
274		cur.s_addr = 0xffffffff;
275		TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
276			in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr;
277			if (ifa->ifa_addr->sa_family == AF_INET &&
278			    ntohl(in.s_addr) > ntohl(last.s_addr) &&
279			    ntohl(in.s_addr) < ntohl(cur.s_addr)) {
280				cur.s_addr = in.s_addr;
281				found++;
282			}
283		}
284		if (found)
285			SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur));
286	} while (found);
287#endif /* INET */
288#ifdef INET6
289	memset(&cur6, 0, sizeof(cur6));
290	do {
291		found = 0;
292		last6 = cur6;
293		memset(&cur6, 0xff, sizeof(cur6));
294		TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
295			in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
296			if (IN6_IS_SCOPE_EMBED(&in6))
297				in6.s6_addr16[1] = 0;
298			if (ifa->ifa_addr->sa_family == AF_INET6 &&
299			    memcmp(&in6, &last6, sizeof(in6)) > 0 &&
300			    memcmp(&in6, &cur6, sizeof(in6)) < 0) {
301				cur6 = in6;
302				found++;
303			}
304		}
305		if (found)
306			SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6));
307	} while (found);
308#endif /* INET6 */
309
310	/* convert ipad to opad */
311	for (i = 0; i < sizeof(sc->sc_pad); i++)
312		sc->sc_pad[i] ^= 0x36 ^ 0x5c;
313
314	if (sc->sc_carpdev)
315		CARP_SCUNLOCK(sc);
316}
317
318static void
319carp_hmac_generate(struct carp_softc *sc, u_int32_t counter[2],
320    unsigned char md[20])
321{
322	SHA1_CTX sha1ctx;
323
324	/* fetch first half of inner hash */
325	bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx));
326
327	SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
328	SHA1Final(md, &sha1ctx);
329
330	/* outer hash */
331	SHA1Init(&sha1ctx);
332	SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
333	SHA1Update(&sha1ctx, md, 20);
334	SHA1Final(md, &sha1ctx);
335}
336
337static int
338carp_hmac_verify(struct carp_softc *sc, u_int32_t counter[2],
339    unsigned char md[20])
340{
341	unsigned char md2[20];
342
343	CARP_SCLOCK_ASSERT(sc);
344
345	carp_hmac_generate(sc, counter, md2);
346
347	return (bcmp(md, md2, sizeof(md2)));
348}
349
350static void
351carp_setroute(struct carp_softc *sc, int cmd)
352{
353	struct ifaddr *ifa;
354	int s;
355
356	if (sc->sc_carpdev)
357		CARP_SCLOCK_ASSERT(sc);
358
359	s = splnet();
360	TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
361		if (ifa->ifa_addr->sa_family == AF_INET &&
362		    sc->sc_carpdev != NULL) {
363			int count = carp_addrcount(
364			    (struct carp_if *)sc->sc_carpdev->if_carp,
365			    ifatoia(ifa), CARP_COUNT_MASTER);
366
367			if ((cmd == RTM_ADD && count == 1) ||
368			    (cmd == RTM_DELETE && count == 0))
369				rtinit(ifa, cmd, RTF_UP | RTF_HOST);
370		}
371#ifdef INET6
372		if (ifa->ifa_addr->sa_family == AF_INET6) {
373			if (cmd == RTM_ADD)
374				in6_ifaddloop(ifa);
375			else
376				in6_ifremloop(ifa);
377		}
378#endif /* INET6 */
379	}
380	splx(s);
381}
382
383static int
384carp_clone_create(struct if_clone *ifc, int unit, caddr_t params)
385{
386
387	struct carp_softc *sc;
388	struct ifnet *ifp;
389
390	MALLOC(sc, struct carp_softc *, sizeof(*sc), M_CARP, M_WAITOK|M_ZERO);
391	ifp = SC2IFP(sc) = if_alloc(IFT_ETHER);
392	if (ifp == NULL) {
393		FREE(sc, M_CARP);
394		return (ENOSPC);
395	}
396
397	sc->sc_flags_backup = 0;
398	sc->sc_suppress = 0;
399	sc->sc_advbase = CARP_DFLTINTV;
400	sc->sc_vhid = -1;	/* required setting */
401	sc->sc_advskew = 0;
402	sc->sc_init_counter = 1;
403	sc->sc_naddrs = sc->sc_naddrs6 = 0; /* M_ZERO? */
404#ifdef INET6
405	sc->sc_im6o.im6o_multicast_hlim = CARP_DFLTTL;
406#endif
407	sc->sc_imo.imo_membership = (struct in_multi **)malloc(
408	    (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP,
409	    M_WAITOK);
410	sc->sc_imo.imo_mfilters = NULL;
411	sc->sc_imo.imo_max_memberships = IP_MIN_MEMBERSHIPS;
412	sc->sc_imo.imo_multicast_vif = -1;
413
414	callout_init(&sc->sc_ad_tmo, CALLOUT_MPSAFE);
415	callout_init(&sc->sc_md_tmo, CALLOUT_MPSAFE);
416	callout_init(&sc->sc_md6_tmo, CALLOUT_MPSAFE);
417
418	ifp->if_softc = sc;
419	if_initname(ifp, CARP_IFNAME, unit);
420	ifp->if_mtu = ETHERMTU;
421	ifp->if_flags = IFF_LOOPBACK;
422	ifp->if_ioctl = carp_ioctl;
423	ifp->if_output = carp_looutput;
424	ifp->if_start = carp_start;
425	ifp->if_type = IFT_CARP;
426	ifp->if_snd.ifq_maxlen = ifqmaxlen;
427	ifp->if_hdrlen = 0;
428	if_attach(ifp);
429	bpfattach(SC2IFP(sc), DLT_NULL, sizeof(u_int32_t));
430	mtx_lock(&carp_mtx);
431	LIST_INSERT_HEAD(&carpif_list, sc, sc_next);
432	mtx_unlock(&carp_mtx);
433	return (0);
434}
435
436static void
437carp_clone_destroy(struct ifnet *ifp)
438{
439	struct carp_softc *sc = ifp->if_softc;
440
441	if (sc->sc_carpdev)
442		CARP_SCLOCK(sc);
443	carpdetach(sc, 1);	/* Returns unlocked. */
444
445	mtx_lock(&carp_mtx);
446	LIST_REMOVE(sc, sc_next);
447	mtx_unlock(&carp_mtx);
448	bpfdetach(ifp);
449	if_detach(ifp);
450	if_free_type(ifp, IFT_ETHER);
451	free(sc->sc_imo.imo_membership, M_CARP);
452	free(sc, M_CARP);
453}
454
455/*
456 * This function can be called on CARP interface destroy path,
457 * and in case of the removal of the underlying interface as
458 * well. We differentiate these two cases. In the latter case
459 * we do not cleanup our multicast memberships, since they
460 * are already freed. Also, in the latter case we do not
461 * release the lock on return, because the function will be
462 * called once more, for another CARP instance on the same
463 * interface.
464 */
465static void
466carpdetach(struct carp_softc *sc, int unlock)
467{
468	struct carp_if *cif;
469
470	callout_stop(&sc->sc_ad_tmo);
471	callout_stop(&sc->sc_md_tmo);
472	callout_stop(&sc->sc_md6_tmo);
473
474	if (sc->sc_suppress)
475		carp_suppress_preempt--;
476	sc->sc_suppress = 0;
477
478	if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS)
479		carp_suppress_preempt--;
480	sc->sc_sendad_errors = 0;
481
482	carp_set_state(sc, INIT);
483	SC2IFP(sc)->if_flags &= ~IFF_UP;
484	carp_setrun(sc, 0);
485	if (unlock)
486		carp_multicast_cleanup(sc);
487#ifdef INET6
488	carp_multicast6_cleanup(sc);
489#endif
490
491	if (sc->sc_carpdev != NULL) {
492		cif = (struct carp_if *)sc->sc_carpdev->if_carp;
493		CARP_LOCK_ASSERT(cif);
494		TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
495		if (!--cif->vhif_nvrs) {
496			ifpromisc(sc->sc_carpdev, 0);
497			sc->sc_carpdev->if_carp = NULL;
498			CARP_LOCK_DESTROY(cif);
499			FREE(cif, M_IFADDR);
500		} else if (unlock)
501			CARP_UNLOCK(cif);
502		sc->sc_carpdev = NULL;
503	}
504}
505
506/* Detach an interface from the carp. */
507static void
508carp_ifdetach(void *arg __unused, struct ifnet *ifp)
509{
510	struct carp_if *cif = (struct carp_if *)ifp->if_carp;
511	struct carp_softc *sc, *nextsc;
512
513	if (cif == NULL)
514		return;
515
516	/*
517	 * XXX: At the end of for() cycle the lock will be destroyed.
518	 */
519	CARP_LOCK(cif);
520	for (sc = TAILQ_FIRST(&cif->vhif_vrs); sc; sc = nextsc) {
521		nextsc = TAILQ_NEXT(sc, sc_list);
522		carpdetach(sc, 0);
523	}
524}
525
526/*
527 * process input packet.
528 * we have rearranged checks order compared to the rfc,
529 * but it seems more efficient this way or not possible otherwise.
530 */
531void
532carp_input(struct mbuf *m, int hlen)
533{
534	struct ip *ip = mtod(m, struct ip *);
535	struct carp_header *ch;
536	int iplen, len;
537
538	carpstats.carps_ipackets++;
539
540	if (!carp_opts[CARPCTL_ALLOW]) {
541		m_freem(m);
542		return;
543	}
544
545	/* check if received on a valid carp interface */
546	if (m->m_pkthdr.rcvif->if_carp == NULL) {
547		carpstats.carps_badif++;
548		CARP_LOG("carp_input: packet received on non-carp "
549		    "interface: %s\n",
550		    m->m_pkthdr.rcvif->if_xname);
551		m_freem(m);
552		return;
553	}
554
555	/* verify that the IP TTL is 255.  */
556	if (ip->ip_ttl != CARP_DFLTTL) {
557		carpstats.carps_badttl++;
558		CARP_LOG("carp_input: received ttl %d != 255i on %s\n",
559		    ip->ip_ttl,
560		    m->m_pkthdr.rcvif->if_xname);
561		m_freem(m);
562		return;
563	}
564
565	iplen = ip->ip_hl << 2;
566
567	if (m->m_pkthdr.len < iplen + sizeof(*ch)) {
568		carpstats.carps_badlen++;
569		CARP_LOG("carp_input: received len %zd < "
570		    "sizeof(struct carp_header)\n",
571		    m->m_len - sizeof(struct ip));
572		m_freem(m);
573		return;
574	}
575
576	if (iplen + sizeof(*ch) < m->m_len) {
577		if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) {
578			carpstats.carps_hdrops++;
579			CARP_LOG("carp_input: pullup failed\n");
580			return;
581		}
582		ip = mtod(m, struct ip *);
583	}
584	ch = (struct carp_header *)((char *)ip + iplen);
585
586	/*
587	 * verify that the received packet length is
588	 * equal to the CARP header
589	 */
590	len = iplen + sizeof(*ch);
591	if (len > m->m_pkthdr.len) {
592		carpstats.carps_badlen++;
593		CARP_LOG("carp_input: packet too short %d on %s\n",
594		    m->m_pkthdr.len,
595		    m->m_pkthdr.rcvif->if_xname);
596		m_freem(m);
597		return;
598	}
599
600	if ((m = m_pullup(m, len)) == NULL) {
601		carpstats.carps_hdrops++;
602		return;
603	}
604	ip = mtod(m, struct ip *);
605	ch = (struct carp_header *)((char *)ip + iplen);
606
607	/* verify the CARP checksum */
608	m->m_data += iplen;
609	if (carp_cksum(m, len - iplen)) {
610		carpstats.carps_badsum++;
611		CARP_LOG("carp_input: checksum failed on %s\n",
612		    m->m_pkthdr.rcvif->if_xname);
613		m_freem(m);
614		return;
615	}
616	m->m_data -= iplen;
617
618	carp_input_c(m, ch, AF_INET);
619}
620
621#ifdef INET6
622int
623carp6_input(struct mbuf **mp, int *offp, int proto)
624{
625	struct mbuf *m = *mp;
626	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
627	struct carp_header *ch;
628	u_int len;
629
630	carpstats.carps_ipackets6++;
631
632	if (!carp_opts[CARPCTL_ALLOW]) {
633		m_freem(m);
634		return (IPPROTO_DONE);
635	}
636
637	/* check if received on a valid carp interface */
638	if (m->m_pkthdr.rcvif->if_carp == NULL) {
639		carpstats.carps_badif++;
640		CARP_LOG("carp6_input: packet received on non-carp "
641		    "interface: %s\n",
642		    m->m_pkthdr.rcvif->if_xname);
643		m_freem(m);
644		return (IPPROTO_DONE);
645	}
646
647	/* verify that the IP TTL is 255 */
648	if (ip6->ip6_hlim != CARP_DFLTTL) {
649		carpstats.carps_badttl++;
650		CARP_LOG("carp6_input: received ttl %d != 255 on %s\n",
651		    ip6->ip6_hlim,
652		    m->m_pkthdr.rcvif->if_xname);
653		m_freem(m);
654		return (IPPROTO_DONE);
655	}
656
657	/* verify that we have a complete carp packet */
658	len = m->m_len;
659	IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch));
660	if (ch == NULL) {
661		carpstats.carps_badlen++;
662		CARP_LOG("carp6_input: packet size %u too small\n", len);
663		return (IPPROTO_DONE);
664	}
665
666
667	/* verify the CARP checksum */
668	m->m_data += *offp;
669	if (carp_cksum(m, sizeof(*ch))) {
670		carpstats.carps_badsum++;
671		CARP_LOG("carp6_input: checksum failed, on %s\n",
672		    m->m_pkthdr.rcvif->if_xname);
673		m_freem(m);
674		return (IPPROTO_DONE);
675	}
676	m->m_data -= *offp;
677
678	carp_input_c(m, ch, AF_INET6);
679	return (IPPROTO_DONE);
680}
681#endif /* INET6 */
682
683static void
684carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
685{
686	struct ifnet *ifp = m->m_pkthdr.rcvif;
687	struct carp_softc *sc;
688	u_int64_t tmp_counter;
689	struct timeval sc_tv, ch_tv;
690
691	/* verify that the VHID is valid on the receiving interface */
692	CARP_LOCK(ifp->if_carp);
693	TAILQ_FOREACH(sc, &((struct carp_if *)ifp->if_carp)->vhif_vrs, sc_list)
694		if (sc->sc_vhid == ch->carp_vhid)
695			break;
696
697	if (!sc || !((SC2IFP(sc)->if_flags & IFF_UP) &&
698	    (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) {
699		carpstats.carps_badvhid++;
700		CARP_UNLOCK(ifp->if_carp);
701		m_freem(m);
702		return;
703	}
704
705	getmicrotime(&SC2IFP(sc)->if_lastchange);
706	SC2IFP(sc)->if_ipackets++;
707	SC2IFP(sc)->if_ibytes += m->m_pkthdr.len;
708
709	if (bpf_peers_present(SC2IFP(sc)->if_bpf)) {
710		struct ip *ip = mtod(m, struct ip *);
711		uint32_t af1 = af;
712
713		/* BPF wants net byte order */
714		ip->ip_len = htons(ip->ip_len + (ip->ip_hl << 2));
715		ip->ip_off = htons(ip->ip_off);
716		bpf_mtap2(SC2IFP(sc)->if_bpf, &af1, sizeof(af1), m);
717	}
718
719	/* verify the CARP version. */
720	if (ch->carp_version != CARP_VERSION) {
721		carpstats.carps_badver++;
722		SC2IFP(sc)->if_ierrors++;
723		CARP_UNLOCK(ifp->if_carp);
724		CARP_LOG("%s; invalid version %d\n",
725		    SC2IFP(sc)->if_xname,
726		    ch->carp_version);
727		m_freem(m);
728		return;
729	}
730
731	/* verify the hash */
732	if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
733		carpstats.carps_badauth++;
734		SC2IFP(sc)->if_ierrors++;
735		CARP_UNLOCK(ifp->if_carp);
736		CARP_LOG("%s: incorrect hash\n", SC2IFP(sc)->if_xname);
737		m_freem(m);
738		return;
739	}
740
741	tmp_counter = ntohl(ch->carp_counter[0]);
742	tmp_counter = tmp_counter<<32;
743	tmp_counter += ntohl(ch->carp_counter[1]);
744
745	/* XXX Replay protection goes here */
746
747	sc->sc_init_counter = 0;
748	sc->sc_counter = tmp_counter;
749
750	sc_tv.tv_sec = sc->sc_advbase;
751	if (carp_suppress_preempt && sc->sc_advskew <  240)
752		sc_tv.tv_usec = 240 * 1000000 / 256;
753	else
754		sc_tv.tv_usec = sc->sc_advskew * 1000000 / 256;
755	ch_tv.tv_sec = ch->carp_advbase;
756	ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
757
758	switch (sc->sc_state) {
759	case INIT:
760		break;
761	case MASTER:
762		/*
763		 * If we receive an advertisement from a master who's going to
764		 * be more frequent than us, go into BACKUP state.
765		 */
766		if (timevalcmp(&sc_tv, &ch_tv, >) ||
767		    timevalcmp(&sc_tv, &ch_tv, ==)) {
768			callout_stop(&sc->sc_ad_tmo);
769			CARP_DEBUG("%s: MASTER -> BACKUP "
770			   "(more frequent advertisement received)\n",
771			   SC2IFP(sc)->if_xname);
772			carp_set_state(sc, BACKUP);
773			carp_setrun(sc, 0);
774			carp_setroute(sc, RTM_DELETE);
775		}
776		break;
777	case BACKUP:
778		/*
779		 * If we're pre-empting masters who advertise slower than us,
780		 * and this one claims to be slower, treat him as down.
781		 */
782		if (carp_opts[CARPCTL_PREEMPT] &&
783		    timevalcmp(&sc_tv, &ch_tv, <)) {
784			CARP_DEBUG("%s: BACKUP -> MASTER "
785			    "(preempting a slower master)\n",
786			    SC2IFP(sc)->if_xname);
787			carp_master_down_locked(sc);
788			break;
789		}
790
791		/*
792		 *  If the master is going to advertise at such a low frequency
793		 *  that he's guaranteed to time out, we'd might as well just
794		 *  treat him as timed out now.
795		 */
796		sc_tv.tv_sec = sc->sc_advbase * 3;
797		if (timevalcmp(&sc_tv, &ch_tv, <)) {
798			CARP_DEBUG("%s: BACKUP -> MASTER "
799			    "(master timed out)\n",
800			    SC2IFP(sc)->if_xname);
801			carp_master_down_locked(sc);
802			break;
803		}
804
805		/*
806		 * Otherwise, we reset the counter and wait for the next
807		 * advertisement.
808		 */
809		carp_setrun(sc, af);
810		break;
811	}
812
813	CARP_UNLOCK(ifp->if_carp);
814
815	m_freem(m);
816	return;
817}
818
819static int
820carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch)
821{
822	struct m_tag *mtag;
823	struct ifnet *ifp = SC2IFP(sc);
824
825	if (sc->sc_init_counter) {
826		/* this could also be seconds since unix epoch */
827		sc->sc_counter = arc4random();
828		sc->sc_counter = sc->sc_counter << 32;
829		sc->sc_counter += arc4random();
830	} else
831		sc->sc_counter++;
832
833	ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
834	ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
835
836	carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
837
838	/* Tag packet for carp_output */
839	mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct ifnet *), M_NOWAIT);
840	if (mtag == NULL) {
841		m_freem(m);
842		SC2IFP(sc)->if_oerrors++;
843		return (ENOMEM);
844	}
845	bcopy(&ifp, (caddr_t)(mtag + 1), sizeof(struct ifnet *));
846	m_tag_prepend(m, mtag);
847
848	return (0);
849}
850
851static void
852carp_send_ad_all(void)
853{
854	struct carp_softc *sc;
855
856	mtx_lock(&carp_mtx);
857	LIST_FOREACH(sc, &carpif_list, sc_next) {
858		if (sc->sc_carpdev == NULL)
859			continue;
860		CARP_SCLOCK(sc);
861		if ((SC2IFP(sc)->if_flags & IFF_UP) &&
862		    (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING) &&
863		     sc->sc_state == MASTER)
864			carp_send_ad_locked(sc);
865		CARP_SCUNLOCK(sc);
866	}
867	mtx_unlock(&carp_mtx);
868}
869
870static void
871carp_send_ad(void *v)
872{
873	struct carp_softc *sc = v;
874
875	CARP_SCLOCK(sc);
876	carp_send_ad_locked(sc);
877	CARP_SCUNLOCK(sc);
878}
879
880static void
881carp_send_ad_locked(struct carp_softc *sc)
882{
883	struct carp_header ch;
884	struct timeval tv;
885	struct carp_header *ch_ptr;
886	struct mbuf *m;
887	int len, advbase, advskew;
888
889	CARP_SCLOCK_ASSERT(sc);
890
891	/* bow out if we've lost our UPness or RUNNINGuiness */
892	if (!((SC2IFP(sc)->if_flags & IFF_UP) &&
893	    (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) {
894		advbase = 255;
895		advskew = 255;
896	} else {
897		advbase = sc->sc_advbase;
898		if (!carp_suppress_preempt || sc->sc_advskew > 240)
899			advskew = sc->sc_advskew;
900		else
901			advskew = 240;
902		tv.tv_sec = advbase;
903		tv.tv_usec = advskew * 1000000 / 256;
904	}
905
906	ch.carp_version = CARP_VERSION;
907	ch.carp_type = CARP_ADVERTISEMENT;
908	ch.carp_vhid = sc->sc_vhid;
909	ch.carp_advbase = advbase;
910	ch.carp_advskew = advskew;
911	ch.carp_authlen = 7;	/* XXX DEFINE */
912	ch.carp_pad1 = 0;	/* must be zero */
913	ch.carp_cksum = 0;
914
915#ifdef INET
916	if (sc->sc_ia) {
917		struct ip *ip;
918
919		MGETHDR(m, M_DONTWAIT, MT_HEADER);
920		if (m == NULL) {
921			SC2IFP(sc)->if_oerrors++;
922			carpstats.carps_onomem++;
923			/* XXX maybe less ? */
924			if (advbase != 255 || advskew != 255)
925				callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
926				    carp_send_ad, sc);
927			return;
928		}
929		len = sizeof(*ip) + sizeof(ch);
930		m->m_pkthdr.len = len;
931		m->m_pkthdr.rcvif = NULL;
932		m->m_len = len;
933		MH_ALIGN(m, m->m_len);
934		m->m_flags |= M_MCAST;
935		ip = mtod(m, struct ip *);
936		ip->ip_v = IPVERSION;
937		ip->ip_hl = sizeof(*ip) >> 2;
938		ip->ip_tos = IPTOS_LOWDELAY;
939		ip->ip_len = len;
940		ip->ip_id = ip_newid();
941		ip->ip_off = IP_DF;
942		ip->ip_ttl = CARP_DFLTTL;
943		ip->ip_p = IPPROTO_CARP;
944		ip->ip_sum = 0;
945		ip->ip_src.s_addr = sc->sc_ia->ia_addr.sin_addr.s_addr;
946		ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP);
947
948		ch_ptr = (struct carp_header *)(&ip[1]);
949		bcopy(&ch, ch_ptr, sizeof(ch));
950		if (carp_prepare_ad(m, sc, ch_ptr))
951			return;
952
953		m->m_data += sizeof(*ip);
954		ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip));
955		m->m_data -= sizeof(*ip);
956
957		getmicrotime(&SC2IFP(sc)->if_lastchange);
958		SC2IFP(sc)->if_opackets++;
959		SC2IFP(sc)->if_obytes += len;
960		carpstats.carps_opackets++;
961
962		if (ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_imo, NULL)) {
963			SC2IFP(sc)->if_oerrors++;
964			if (sc->sc_sendad_errors < INT_MAX)
965				sc->sc_sendad_errors++;
966			if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
967				carp_suppress_preempt++;
968				if (carp_suppress_preempt == 1) {
969					CARP_SCUNLOCK(sc);
970					carp_send_ad_all();
971					CARP_SCLOCK(sc);
972				}
973			}
974			sc->sc_sendad_success = 0;
975		} else {
976			if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
977				if (++sc->sc_sendad_success >=
978				    CARP_SENDAD_MIN_SUCCESS) {
979					carp_suppress_preempt--;
980					sc->sc_sendad_errors = 0;
981				}
982			} else
983				sc->sc_sendad_errors = 0;
984		}
985	}
986#endif /* INET */
987#ifdef INET6
988	if (sc->sc_ia6) {
989		struct ip6_hdr *ip6;
990
991		MGETHDR(m, M_DONTWAIT, MT_HEADER);
992		if (m == NULL) {
993			SC2IFP(sc)->if_oerrors++;
994			carpstats.carps_onomem++;
995			/* XXX maybe less ? */
996			if (advbase != 255 || advskew != 255)
997				callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
998				    carp_send_ad, sc);
999			return;
1000		}
1001		len = sizeof(*ip6) + sizeof(ch);
1002		m->m_pkthdr.len = len;
1003		m->m_pkthdr.rcvif = NULL;
1004		m->m_len = len;
1005		MH_ALIGN(m, m->m_len);
1006		m->m_flags |= M_MCAST;
1007		ip6 = mtod(m, struct ip6_hdr *);
1008		bzero(ip6, sizeof(*ip6));
1009		ip6->ip6_vfc |= IPV6_VERSION;
1010		ip6->ip6_hlim = CARP_DFLTTL;
1011		ip6->ip6_nxt = IPPROTO_CARP;
1012		bcopy(&sc->sc_ia6->ia_addr.sin6_addr, &ip6->ip6_src,
1013		    sizeof(struct in6_addr));
1014		/* set the multicast destination */
1015
1016		ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
1017		ip6->ip6_dst.s6_addr8[15] = 0x12;
1018		if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) {
1019			SC2IFP(sc)->if_oerrors++;
1020			m_freem(m);
1021			CARP_LOG("%s: in6_setscope failed\n", __func__);
1022			return;
1023		}
1024
1025		ch_ptr = (struct carp_header *)(&ip6[1]);
1026		bcopy(&ch, ch_ptr, sizeof(ch));
1027		if (carp_prepare_ad(m, sc, ch_ptr))
1028			return;
1029
1030		m->m_data += sizeof(*ip6);
1031		ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip6));
1032		m->m_data -= sizeof(*ip6);
1033
1034		getmicrotime(&SC2IFP(sc)->if_lastchange);
1035		SC2IFP(sc)->if_opackets++;
1036		SC2IFP(sc)->if_obytes += len;
1037		carpstats.carps_opackets6++;
1038
1039		if (ip6_output(m, NULL, NULL, 0, &sc->sc_im6o, NULL, NULL)) {
1040			SC2IFP(sc)->if_oerrors++;
1041			if (sc->sc_sendad_errors < INT_MAX)
1042				sc->sc_sendad_errors++;
1043			if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
1044				carp_suppress_preempt++;
1045				if (carp_suppress_preempt == 1) {
1046					CARP_SCUNLOCK(sc);
1047					carp_send_ad_all();
1048					CARP_SCLOCK(sc);
1049				}
1050			}
1051			sc->sc_sendad_success = 0;
1052		} else {
1053			if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
1054				if (++sc->sc_sendad_success >=
1055				    CARP_SENDAD_MIN_SUCCESS) {
1056					carp_suppress_preempt--;
1057					sc->sc_sendad_errors = 0;
1058				}
1059			} else
1060				sc->sc_sendad_errors = 0;
1061		}
1062	}
1063#endif /* INET6 */
1064
1065	if (advbase != 255 || advskew != 255)
1066		callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
1067		    carp_send_ad, sc);
1068
1069}
1070
1071/*
1072 * Broadcast a gratuitous ARP request containing
1073 * the virtual router MAC address for each IP address
1074 * associated with the virtual router.
1075 */
1076static void
1077carp_send_arp(struct carp_softc *sc)
1078{
1079	struct ifaddr *ifa;
1080
1081	TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
1082
1083		if (ifa->ifa_addr->sa_family != AF_INET)
1084			continue;
1085
1086/*		arprequest(sc->sc_carpdev, &in, &in, IF_LLADDR(sc->sc_ifp)); */
1087		arp_ifinit2(sc->sc_carpdev, ifa, IF_LLADDR(sc->sc_ifp));
1088
1089		DELAY(1000);	/* XXX */
1090	}
1091}
1092
1093#ifdef INET6
1094static void
1095carp_send_na(struct carp_softc *sc)
1096{
1097	struct ifaddr *ifa;
1098	struct in6_addr *in6;
1099	static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
1100
1101	TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
1102
1103		if (ifa->ifa_addr->sa_family != AF_INET6)
1104			continue;
1105
1106		in6 = &ifatoia6(ifa)->ia_addr.sin6_addr;
1107		nd6_na_output(sc->sc_carpdev, &mcast, in6,
1108		    ND_NA_FLAG_OVERRIDE, 1, NULL);
1109		DELAY(1000);	/* XXX */
1110	}
1111}
1112#endif /* INET6 */
1113
1114static int
1115carp_addrcount(struct carp_if *cif, struct in_ifaddr *ia, int type)
1116{
1117	struct carp_softc *vh;
1118	struct ifaddr *ifa;
1119	int count = 0;
1120
1121	CARP_LOCK_ASSERT(cif);
1122
1123	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1124		if ((type == CARP_COUNT_RUNNING &&
1125		    (SC2IFP(vh)->if_flags & IFF_UP) &&
1126		    (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) ||
1127		    (type == CARP_COUNT_MASTER && vh->sc_state == MASTER)) {
1128			TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist,
1129			    ifa_list) {
1130				if (ifa->ifa_addr->sa_family == AF_INET &&
1131				    ia->ia_addr.sin_addr.s_addr ==
1132				    ifatoia(ifa)->ia_addr.sin_addr.s_addr)
1133					count++;
1134			}
1135		}
1136	}
1137	return (count);
1138}
1139
1140int
1141carp_iamatch(void *v, struct in_ifaddr *ia,
1142    struct in_addr *isaddr, u_int8_t **enaddr)
1143{
1144	struct carp_if *cif = v;
1145	struct carp_softc *vh;
1146	int index, count = 0;
1147	struct ifaddr *ifa;
1148
1149	CARP_LOCK(cif);
1150
1151	if (carp_opts[CARPCTL_ARPBALANCE]) {
1152		/*
1153		 * XXX proof of concept implementation.
1154		 * We use the source ip to decide which virtual host should
1155		 * handle the request. If we're master of that virtual host,
1156		 * then we respond, otherwise, just drop the arp packet on
1157		 * the floor.
1158		 */
1159		count = carp_addrcount(cif, ia, CARP_COUNT_RUNNING);
1160		if (count == 0) {
1161			/* should never reach this */
1162			CARP_UNLOCK(cif);
1163			return (0);
1164		}
1165
1166		/* this should be a hash, like pf_hash() */
1167		index = ntohl(isaddr->s_addr) % count;
1168		count = 0;
1169
1170		TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1171			if ((SC2IFP(vh)->if_flags & IFF_UP) &&
1172			    (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) {
1173				TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist,
1174				    ifa_list) {
1175					if (ifa->ifa_addr->sa_family ==
1176					    AF_INET &&
1177					    ia->ia_addr.sin_addr.s_addr ==
1178					    ifatoia(ifa)->ia_addr.sin_addr.s_addr) {
1179						if (count == index) {
1180							if (vh->sc_state ==
1181							    MASTER) {
1182								*enaddr = IF_LLADDR(vh->sc_ifp);
1183								CARP_UNLOCK(cif);
1184								return (1);
1185							} else {
1186								CARP_UNLOCK(cif);
1187								return (0);
1188							}
1189						}
1190						count++;
1191					}
1192				}
1193			}
1194		}
1195	} else {
1196		TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1197			if ((SC2IFP(vh)->if_flags & IFF_UP) &&
1198			    (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
1199			    ia->ia_ifp == SC2IFP(vh) &&
1200			    vh->sc_state == MASTER) {
1201				*enaddr = IF_LLADDR(vh->sc_ifp);
1202				CARP_UNLOCK(cif);
1203				return (1);
1204			}
1205		}
1206	}
1207	CARP_UNLOCK(cif);
1208	return (0);
1209}
1210
1211#ifdef INET6
1212struct ifaddr *
1213carp_iamatch6(void *v, struct in6_addr *taddr)
1214{
1215	struct carp_if *cif = v;
1216	struct carp_softc *vh;
1217	struct ifaddr *ifa;
1218
1219	CARP_LOCK(cif);
1220	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) {
1221		TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist, ifa_list) {
1222			if (IN6_ARE_ADDR_EQUAL(taddr,
1223			    &ifatoia6(ifa)->ia_addr.sin6_addr) &&
1224 			    (SC2IFP(vh)->if_flags & IFF_UP) &&
1225			    (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
1226			    vh->sc_state == MASTER) {
1227			    	CARP_UNLOCK(cif);
1228				return (ifa);
1229			}
1230		}
1231	}
1232	CARP_UNLOCK(cif);
1233
1234	return (NULL);
1235}
1236
1237void *
1238carp_macmatch6(void *v, struct mbuf *m, const struct in6_addr *taddr)
1239{
1240	struct m_tag *mtag;
1241	struct carp_if *cif = v;
1242	struct carp_softc *sc;
1243	struct ifaddr *ifa;
1244
1245	CARP_LOCK(cif);
1246	TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) {
1247		TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) {
1248			if (IN6_ARE_ADDR_EQUAL(taddr,
1249			    &ifatoia6(ifa)->ia_addr.sin6_addr) &&
1250 			    (SC2IFP(sc)->if_flags & IFF_UP) &&
1251			    (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING)) {
1252				struct ifnet *ifp = SC2IFP(sc);
1253				mtag = m_tag_get(PACKET_TAG_CARP,
1254				    sizeof(struct ifnet *), M_NOWAIT);
1255				if (mtag == NULL) {
1256					/* better a bit than nothing */
1257					CARP_UNLOCK(cif);
1258					return (IF_LLADDR(sc->sc_ifp));
1259				}
1260				bcopy(&ifp, (caddr_t)(mtag + 1),
1261				    sizeof(struct ifnet *));
1262				m_tag_prepend(m, mtag);
1263
1264				CARP_UNLOCK(cif);
1265				return (IF_LLADDR(sc->sc_ifp));
1266			}
1267		}
1268	}
1269	CARP_UNLOCK(cif);
1270
1271	return (NULL);
1272}
1273#endif
1274
1275struct ifnet *
1276carp_forus(void *v, void *dhost)
1277{
1278	struct carp_if *cif = v;
1279	struct carp_softc *vh;
1280	u_int8_t *ena = dhost;
1281
1282	if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
1283		return (NULL);
1284
1285	CARP_LOCK(cif);
1286	TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list)
1287		if ((SC2IFP(vh)->if_flags & IFF_UP) &&
1288		    (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) &&
1289		    vh->sc_state == MASTER &&
1290		    !bcmp(dhost, IF_LLADDR(vh->sc_ifp), ETHER_ADDR_LEN)) {
1291		    	CARP_UNLOCK(cif);
1292			return (SC2IFP(vh));
1293		}
1294
1295    	CARP_UNLOCK(cif);
1296	return (NULL);
1297}
1298
1299static void
1300carp_master_down(void *v)
1301{
1302	struct carp_softc *sc = v;
1303
1304	CARP_SCLOCK(sc);
1305	carp_master_down_locked(sc);
1306	CARP_SCUNLOCK(sc);
1307}
1308
1309static void
1310carp_master_down_locked(struct carp_softc *sc)
1311{
1312	if (sc->sc_carpdev)
1313		CARP_SCLOCK_ASSERT(sc);
1314
1315	switch (sc->sc_state) {
1316	case INIT:
1317		printf("%s: master_down event in INIT state\n",
1318		    SC2IFP(sc)->if_xname);
1319		break;
1320	case MASTER:
1321		break;
1322	case BACKUP:
1323		carp_set_state(sc, MASTER);
1324		carp_send_ad_locked(sc);
1325		carp_send_arp(sc);
1326#ifdef INET6
1327		carp_send_na(sc);
1328#endif /* INET6 */
1329		carp_setrun(sc, 0);
1330		carp_setroute(sc, RTM_ADD);
1331		break;
1332	}
1333}
1334
1335/*
1336 * When in backup state, af indicates whether to reset the master down timer
1337 * for v4 or v6. If it's set to zero, reset the ones which are already pending.
1338 */
1339static void
1340carp_setrun(struct carp_softc *sc, sa_family_t af)
1341{
1342	struct timeval tv;
1343
1344	if (sc->sc_carpdev == NULL) {
1345		SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
1346		carp_set_state(sc, INIT);
1347		return;
1348	} else
1349		CARP_SCLOCK_ASSERT(sc);
1350
1351	if (SC2IFP(sc)->if_flags & IFF_UP &&
1352	    sc->sc_vhid > 0 && (sc->sc_naddrs || sc->sc_naddrs6))
1353		SC2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING;
1354	else {
1355		SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
1356		carp_setroute(sc, RTM_DELETE);
1357		return;
1358	}
1359
1360	switch (sc->sc_state) {
1361	case INIT:
1362		if (carp_opts[CARPCTL_PREEMPT] && !carp_suppress_preempt) {
1363			carp_send_ad_locked(sc);
1364			carp_send_arp(sc);
1365#ifdef INET6
1366			carp_send_na(sc);
1367#endif /* INET6 */
1368			CARP_DEBUG("%s: INIT -> MASTER (preempting)\n",
1369			    SC2IFP(sc)->if_xname);
1370			carp_set_state(sc, MASTER);
1371			carp_setroute(sc, RTM_ADD);
1372		} else {
1373			CARP_DEBUG("%s: INIT -> BACKUP\n", SC2IFP(sc)->if_xname);
1374			carp_set_state(sc, BACKUP);
1375			carp_setroute(sc, RTM_DELETE);
1376			carp_setrun(sc, 0);
1377		}
1378		break;
1379	case BACKUP:
1380		callout_stop(&sc->sc_ad_tmo);
1381		tv.tv_sec = 3 * sc->sc_advbase;
1382		tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1383		switch (af) {
1384#ifdef INET
1385		case AF_INET:
1386			callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1387			    carp_master_down, sc);
1388			break;
1389#endif /* INET */
1390#ifdef INET6
1391		case AF_INET6:
1392			callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1393			    carp_master_down, sc);
1394			break;
1395#endif /* INET6 */
1396		default:
1397			if (sc->sc_naddrs)
1398				callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1399				    carp_master_down, sc);
1400			if (sc->sc_naddrs6)
1401				callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1402				    carp_master_down, sc);
1403			break;
1404		}
1405		break;
1406	case MASTER:
1407		tv.tv_sec = sc->sc_advbase;
1408		tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1409		callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
1410		    carp_send_ad, sc);
1411		break;
1412	}
1413}
1414
1415static void
1416carp_multicast_cleanup(struct carp_softc *sc)
1417{
1418	struct ip_moptions *imo = &sc->sc_imo;
1419	u_int16_t n = imo->imo_num_memberships;
1420
1421	/* Clean up our own multicast memberships */
1422	while (n-- > 0) {
1423		if (imo->imo_membership[n] != NULL) {
1424			in_delmulti(imo->imo_membership[n]);
1425			imo->imo_membership[n] = NULL;
1426		}
1427	}
1428	KASSERT(imo->imo_mfilters == NULL,
1429	   ("%s: imo_mfilters != NULL", __func__));
1430	imo->imo_num_memberships = 0;
1431	imo->imo_multicast_ifp = NULL;
1432}
1433
1434#ifdef INET6
1435static void
1436carp_multicast6_cleanup(struct carp_softc *sc)
1437{
1438	struct ip6_moptions *im6o = &sc->sc_im6o;
1439
1440	while (!LIST_EMPTY(&im6o->im6o_memberships)) {
1441		struct in6_multi_mship *imm =
1442		    LIST_FIRST(&im6o->im6o_memberships);
1443
1444		LIST_REMOVE(imm, i6mm_chain);
1445		in6_leavegroup(imm);
1446	}
1447	im6o->im6o_multicast_ifp = NULL;
1448}
1449#endif
1450
1451static int
1452carp_set_addr(struct carp_softc *sc, struct sockaddr_in *sin)
1453{
1454	struct ifnet *ifp;
1455	struct carp_if *cif;
1456	struct in_ifaddr *ia, *ia_if;
1457	struct ip_moptions *imo = &sc->sc_imo;
1458	struct in_addr addr;
1459	u_long iaddr = htonl(sin->sin_addr.s_addr);
1460	int own, error;
1461
1462	if (sin->sin_addr.s_addr == 0) {
1463		if (!(SC2IFP(sc)->if_flags & IFF_UP))
1464			carp_set_state(sc, INIT);
1465		if (sc->sc_naddrs)
1466			SC2IFP(sc)->if_flags |= IFF_UP;
1467		carp_setrun(sc, 0);
1468		return (0);
1469	}
1470
1471	/* we have to do it by hands to check we won't match on us */
1472	ia_if = NULL; own = 0;
1473	TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) {
1474		/* and, yeah, we need a multicast-capable iface too */
1475		if (ia->ia_ifp != SC2IFP(sc) &&
1476		    (ia->ia_ifp->if_flags & IFF_MULTICAST) &&
1477		    (iaddr & ia->ia_subnetmask) == ia->ia_subnet) {
1478			if (!ia_if)
1479				ia_if = ia;
1480			if (sin->sin_addr.s_addr ==
1481			    ia->ia_addr.sin_addr.s_addr)
1482				own++;
1483		}
1484	}
1485
1486	if (!ia_if)
1487		return (EADDRNOTAVAIL);
1488
1489	ia = ia_if;
1490	ifp = ia->ia_ifp;
1491
1492	if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 ||
1493	    (imo->imo_multicast_ifp && imo->imo_multicast_ifp != ifp))
1494		return (EADDRNOTAVAIL);
1495
1496	if (imo->imo_num_memberships == 0) {
1497		addr.s_addr = htonl(INADDR_CARP_GROUP);
1498		if ((imo->imo_membership[0] = in_addmulti(&addr, ifp)) == NULL)
1499			return (ENOBUFS);
1500		imo->imo_num_memberships++;
1501		imo->imo_multicast_ifp = ifp;
1502		imo->imo_multicast_ttl = CARP_DFLTTL;
1503		imo->imo_multicast_loop = 0;
1504	}
1505
1506	if (!ifp->if_carp) {
1507
1508		MALLOC(cif, struct carp_if *, sizeof(*cif), M_CARP,
1509		    M_WAITOK|M_ZERO);
1510		if (!cif) {
1511			error = ENOBUFS;
1512			goto cleanup;
1513		}
1514		if ((error = ifpromisc(ifp, 1))) {
1515			FREE(cif, M_CARP);
1516			goto cleanup;
1517		}
1518
1519		CARP_LOCK_INIT(cif);
1520		CARP_LOCK(cif);
1521		cif->vhif_ifp = ifp;
1522		TAILQ_INIT(&cif->vhif_vrs);
1523		ifp->if_carp = cif;
1524
1525	} else {
1526		struct carp_softc *vr;
1527
1528		cif = (struct carp_if *)ifp->if_carp;
1529		CARP_LOCK(cif);
1530		TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
1531			if (vr != sc && vr->sc_vhid == sc->sc_vhid) {
1532				CARP_UNLOCK(cif);
1533				error = EEXIST;
1534				goto cleanup;
1535			}
1536	}
1537	sc->sc_ia = ia;
1538	sc->sc_carpdev = ifp;
1539
1540	{ /* XXX prevent endless loop if already in queue */
1541	struct carp_softc *vr, *after = NULL;
1542	int myself = 0;
1543	cif = (struct carp_if *)ifp->if_carp;
1544
1545	/* XXX: cif should not change, right? So we still hold the lock */
1546	CARP_LOCK_ASSERT(cif);
1547
1548	TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) {
1549		if (vr == sc)
1550			myself = 1;
1551		if (vr->sc_vhid < sc->sc_vhid)
1552			after = vr;
1553	}
1554
1555	if (!myself) {
1556		/* We're trying to keep things in order */
1557		if (after == NULL) {
1558			TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list);
1559		} else {
1560			TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list);
1561		}
1562		cif->vhif_nvrs++;
1563	}
1564	}
1565
1566	sc->sc_naddrs++;
1567	SC2IFP(sc)->if_flags |= IFF_UP;
1568	if (own)
1569		sc->sc_advskew = 0;
1570	carp_sc_state_locked(sc);
1571	carp_setrun(sc, 0);
1572
1573	CARP_UNLOCK(cif);
1574
1575	return (0);
1576
1577cleanup:
1578	in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
1579	return (error);
1580}
1581
1582static int
1583carp_del_addr(struct carp_softc *sc, struct sockaddr_in *sin)
1584{
1585	int error = 0;
1586
1587	if (!--sc->sc_naddrs) {
1588		struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp;
1589		struct ip_moptions *imo = &sc->sc_imo;
1590
1591		CARP_LOCK(cif);
1592		callout_stop(&sc->sc_ad_tmo);
1593		SC2IFP(sc)->if_flags &= ~IFF_UP;
1594		SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
1595		sc->sc_vhid = -1;
1596		in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
1597		imo->imo_multicast_ifp = NULL;
1598		TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
1599		if (!--cif->vhif_nvrs) {
1600			sc->sc_carpdev->if_carp = NULL;
1601			CARP_LOCK_DESTROY(cif);
1602			FREE(cif, M_IFADDR);
1603		} else {
1604			CARP_UNLOCK(cif);
1605		}
1606	}
1607
1608	return (error);
1609}
1610
1611#ifdef INET6
1612static int
1613carp_set_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6)
1614{
1615	struct ifnet *ifp;
1616	struct carp_if *cif;
1617	struct in6_ifaddr *ia, *ia_if;
1618	struct ip6_moptions *im6o = &sc->sc_im6o;
1619	struct in6_multi_mship *imm;
1620	struct in6_addr in6;
1621	int own, error;
1622
1623	if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
1624		if (!(SC2IFP(sc)->if_flags & IFF_UP))
1625			carp_set_state(sc, INIT);
1626		if (sc->sc_naddrs6)
1627			SC2IFP(sc)->if_flags |= IFF_UP;
1628		carp_setrun(sc, 0);
1629		return (0);
1630	}
1631
1632	/* we have to do it by hands to check we won't match on us */
1633	ia_if = NULL; own = 0;
1634	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
1635		int i;
1636
1637		for (i = 0; i < 4; i++) {
1638			if ((sin6->sin6_addr.s6_addr32[i] &
1639			    ia->ia_prefixmask.sin6_addr.s6_addr32[i]) !=
1640			    (ia->ia_addr.sin6_addr.s6_addr32[i] &
1641			    ia->ia_prefixmask.sin6_addr.s6_addr32[i]))
1642				break;
1643		}
1644		/* and, yeah, we need a multicast-capable iface too */
1645		if (ia->ia_ifp != SC2IFP(sc) &&
1646		    (ia->ia_ifp->if_flags & IFF_MULTICAST) &&
1647		    (i == 4)) {
1648			if (!ia_if)
1649				ia_if = ia;
1650			if (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr,
1651			    &ia->ia_addr.sin6_addr))
1652				own++;
1653		}
1654	}
1655
1656	if (!ia_if)
1657		return (EADDRNOTAVAIL);
1658	ia = ia_if;
1659	ifp = ia->ia_ifp;
1660
1661	if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 ||
1662	    (im6o->im6o_multicast_ifp && im6o->im6o_multicast_ifp != ifp))
1663		return (EADDRNOTAVAIL);
1664
1665	if (!sc->sc_naddrs6) {
1666		im6o->im6o_multicast_ifp = ifp;
1667
1668		/* join CARP multicast address */
1669		bzero(&in6, sizeof(in6));
1670		in6.s6_addr16[0] = htons(0xff02);
1671		in6.s6_addr8[15] = 0x12;
1672		if (in6_setscope(&in6, ifp, NULL) != 0)
1673			goto cleanup;
1674		if ((imm = in6_joingroup(ifp, &in6, &error, 0)) == NULL)
1675			goto cleanup;
1676		LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
1677
1678		/* join solicited multicast address */
1679		bzero(&in6, sizeof(in6));
1680		in6.s6_addr16[0] = htons(0xff02);
1681		in6.s6_addr32[1] = 0;
1682		in6.s6_addr32[2] = htonl(1);
1683		in6.s6_addr32[3] = sin6->sin6_addr.s6_addr32[3];
1684		in6.s6_addr8[12] = 0xff;
1685		if (in6_setscope(&in6, ifp, NULL) != 0)
1686			goto cleanup;
1687		if ((imm = in6_joingroup(ifp, &in6, &error, 0)) == NULL)
1688			goto cleanup;
1689		LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain);
1690	}
1691
1692	if (!ifp->if_carp) {
1693		MALLOC(cif, struct carp_if *, sizeof(*cif), M_CARP,
1694		    M_WAITOK|M_ZERO);
1695		if (!cif) {
1696			error = ENOBUFS;
1697			goto cleanup;
1698		}
1699		if ((error = ifpromisc(ifp, 1))) {
1700			FREE(cif, M_CARP);
1701			goto cleanup;
1702		}
1703
1704		CARP_LOCK_INIT(cif);
1705		CARP_LOCK(cif);
1706		cif->vhif_ifp = ifp;
1707		TAILQ_INIT(&cif->vhif_vrs);
1708		ifp->if_carp = cif;
1709
1710	} else {
1711		struct carp_softc *vr;
1712
1713		cif = (struct carp_if *)ifp->if_carp;
1714		CARP_LOCK(cif);
1715		TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
1716			if (vr != sc && vr->sc_vhid == sc->sc_vhid) {
1717				CARP_UNLOCK(cif);
1718				error = EINVAL;
1719				goto cleanup;
1720			}
1721	}
1722	sc->sc_ia6 = ia;
1723	sc->sc_carpdev = ifp;
1724
1725	{ /* XXX prevent endless loop if already in queue */
1726	struct carp_softc *vr, *after = NULL;
1727	int myself = 0;
1728	cif = (struct carp_if *)ifp->if_carp;
1729	CARP_LOCK_ASSERT(cif);
1730
1731	TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) {
1732		if (vr == sc)
1733			myself = 1;
1734		if (vr->sc_vhid < sc->sc_vhid)
1735			after = vr;
1736	}
1737
1738	if (!myself) {
1739		/* We're trying to keep things in order */
1740		if (after == NULL) {
1741			TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list);
1742		} else {
1743			TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list);
1744		}
1745		cif->vhif_nvrs++;
1746	}
1747	}
1748
1749	sc->sc_naddrs6++;
1750	SC2IFP(sc)->if_flags |= IFF_UP;
1751	if (own)
1752		sc->sc_advskew = 0;
1753	carp_sc_state_locked(sc);
1754	carp_setrun(sc, 0);
1755
1756	CARP_UNLOCK(cif);
1757
1758	return (0);
1759
1760cleanup:
1761	/* clean up multicast memberships */
1762	if (!sc->sc_naddrs6) {
1763		while (!LIST_EMPTY(&im6o->im6o_memberships)) {
1764			imm = LIST_FIRST(&im6o->im6o_memberships);
1765			LIST_REMOVE(imm, i6mm_chain);
1766			in6_leavegroup(imm);
1767		}
1768	}
1769	return (error);
1770}
1771
1772static int
1773carp_del_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6)
1774{
1775	int error = 0;
1776
1777	if (!--sc->sc_naddrs6) {
1778		struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp;
1779		struct ip6_moptions *im6o = &sc->sc_im6o;
1780
1781		CARP_LOCK(cif);
1782		callout_stop(&sc->sc_ad_tmo);
1783		SC2IFP(sc)->if_flags &= ~IFF_UP;
1784		SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
1785		sc->sc_vhid = -1;
1786		while (!LIST_EMPTY(&im6o->im6o_memberships)) {
1787			struct in6_multi_mship *imm =
1788			    LIST_FIRST(&im6o->im6o_memberships);
1789
1790			LIST_REMOVE(imm, i6mm_chain);
1791			in6_leavegroup(imm);
1792		}
1793		im6o->im6o_multicast_ifp = NULL;
1794		TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list);
1795		if (!--cif->vhif_nvrs) {
1796			CARP_LOCK_DESTROY(cif);
1797			sc->sc_carpdev->if_carp = NULL;
1798			FREE(cif, M_IFADDR);
1799		} else
1800			CARP_UNLOCK(cif);
1801	}
1802
1803	return (error);
1804}
1805#endif /* INET6 */
1806
1807static int
1808carp_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr)
1809{
1810	struct carp_softc *sc = ifp->if_softc, *vr;
1811	struct carpreq carpr;
1812	struct ifaddr *ifa;
1813	struct ifreq *ifr;
1814	struct ifaliasreq *ifra;
1815	int locked = 0, error = 0;
1816
1817	ifa = (struct ifaddr *)addr;
1818	ifra = (struct ifaliasreq *)addr;
1819	ifr = (struct ifreq *)addr;
1820
1821	switch (cmd) {
1822	case SIOCSIFADDR:
1823		switch (ifa->ifa_addr->sa_family) {
1824#ifdef INET
1825		case AF_INET:
1826			SC2IFP(sc)->if_flags |= IFF_UP;
1827			bcopy(ifa->ifa_addr, ifa->ifa_dstaddr,
1828			    sizeof(struct sockaddr));
1829			error = carp_set_addr(sc, satosin(ifa->ifa_addr));
1830			break;
1831#endif /* INET */
1832#ifdef INET6
1833		case AF_INET6:
1834			SC2IFP(sc)->if_flags |= IFF_UP;
1835			error = carp_set_addr6(sc, satosin6(ifa->ifa_addr));
1836			break;
1837#endif /* INET6 */
1838		default:
1839			error = EAFNOSUPPORT;
1840			break;
1841		}
1842		break;
1843
1844	case SIOCAIFADDR:
1845		switch (ifa->ifa_addr->sa_family) {
1846#ifdef INET
1847		case AF_INET:
1848			SC2IFP(sc)->if_flags |= IFF_UP;
1849			bcopy(ifa->ifa_addr, ifa->ifa_dstaddr,
1850			    sizeof(struct sockaddr));
1851			error = carp_set_addr(sc, satosin(&ifra->ifra_addr));
1852			break;
1853#endif /* INET */
1854#ifdef INET6
1855		case AF_INET6:
1856			SC2IFP(sc)->if_flags |= IFF_UP;
1857			error = carp_set_addr6(sc, satosin6(&ifra->ifra_addr));
1858			break;
1859#endif /* INET6 */
1860		default:
1861			error = EAFNOSUPPORT;
1862			break;
1863		}
1864		break;
1865
1866	case SIOCDIFADDR:
1867		switch (ifa->ifa_addr->sa_family) {
1868#ifdef INET
1869		case AF_INET:
1870			error = carp_del_addr(sc, satosin(&ifra->ifra_addr));
1871			break;
1872#endif /* INET */
1873#ifdef INET6
1874		case AF_INET6:
1875			error = carp_del_addr6(sc, satosin6(&ifra->ifra_addr));
1876			break;
1877#endif /* INET6 */
1878		default:
1879			error = EAFNOSUPPORT;
1880			break;
1881		}
1882		break;
1883
1884	case SIOCSIFFLAGS:
1885		if (sc->sc_carpdev) {
1886			locked = 1;
1887			CARP_SCLOCK(sc);
1888		}
1889		if (sc->sc_state != INIT && !(ifr->ifr_flags & IFF_UP)) {
1890 			callout_stop(&sc->sc_ad_tmo);
1891 			callout_stop(&sc->sc_md_tmo);
1892 			callout_stop(&sc->sc_md6_tmo);
1893			if (sc->sc_state == MASTER)
1894				carp_send_ad_locked(sc);
1895			carp_set_state(sc, INIT);
1896			carp_setrun(sc, 0);
1897		} else if (sc->sc_state == INIT && (ifr->ifr_flags & IFF_UP)) {
1898			SC2IFP(sc)->if_flags |= IFF_UP;
1899			carp_setrun(sc, 0);
1900		}
1901		break;
1902
1903	case SIOCSVH:
1904		error = priv_check(curthread, PRIV_NETINET_CARP);
1905		if (error)
1906			break;
1907		if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr)))
1908			break;
1909		error = 1;
1910		if (sc->sc_carpdev) {
1911			locked = 1;
1912			CARP_SCLOCK(sc);
1913		}
1914		if (sc->sc_state != INIT && carpr.carpr_state != sc->sc_state) {
1915			switch (carpr.carpr_state) {
1916			case BACKUP:
1917				callout_stop(&sc->sc_ad_tmo);
1918				carp_set_state(sc, BACKUP);
1919				carp_setrun(sc, 0);
1920				carp_setroute(sc, RTM_DELETE);
1921				break;
1922			case MASTER:
1923				carp_master_down_locked(sc);
1924				break;
1925			default:
1926				break;
1927			}
1928		}
1929		if (carpr.carpr_vhid > 0) {
1930			if (carpr.carpr_vhid > 255) {
1931				error = EINVAL;
1932				break;
1933			}
1934			if (sc->sc_carpdev) {
1935				struct carp_if *cif;
1936				cif = (struct carp_if *)sc->sc_carpdev->if_carp;
1937				TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list)
1938					if (vr != sc &&
1939					    vr->sc_vhid == carpr.carpr_vhid) {
1940						error = EEXIST;
1941						break;
1942					}
1943				if (error == EEXIST)
1944					break;
1945			}
1946			sc->sc_vhid = carpr.carpr_vhid;
1947			IF_LLADDR(sc->sc_ifp)[0] = 0;
1948			IF_LLADDR(sc->sc_ifp)[1] = 0;
1949			IF_LLADDR(sc->sc_ifp)[2] = 0x5e;
1950			IF_LLADDR(sc->sc_ifp)[3] = 0;
1951			IF_LLADDR(sc->sc_ifp)[4] = 1;
1952			IF_LLADDR(sc->sc_ifp)[5] = sc->sc_vhid;
1953			error--;
1954		}
1955		if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) {
1956			if (carpr.carpr_advskew >= 255) {
1957				error = EINVAL;
1958				break;
1959			}
1960			if (carpr.carpr_advbase > 255) {
1961				error = EINVAL;
1962				break;
1963			}
1964			sc->sc_advbase = carpr.carpr_advbase;
1965			sc->sc_advskew = carpr.carpr_advskew;
1966			error--;
1967		}
1968		bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key));
1969		if (error > 0)
1970			error = EINVAL;
1971		else {
1972			error = 0;
1973			carp_setrun(sc, 0);
1974		}
1975		break;
1976
1977	case SIOCGVH:
1978		/* XXX: lockless read */
1979		bzero(&carpr, sizeof(carpr));
1980		carpr.carpr_state = sc->sc_state;
1981		carpr.carpr_vhid = sc->sc_vhid;
1982		carpr.carpr_advbase = sc->sc_advbase;
1983		carpr.carpr_advskew = sc->sc_advskew;
1984		error = priv_check(curthread, PRIV_NETINET_CARP);
1985		if (error == 0)
1986			bcopy(sc->sc_key, carpr.carpr_key,
1987			    sizeof(carpr.carpr_key));
1988		error = copyout(&carpr, ifr->ifr_data, sizeof(carpr));
1989		break;
1990
1991	default:
1992		error = EINVAL;
1993	}
1994
1995	if (locked)
1996		CARP_SCUNLOCK(sc);
1997
1998	carp_hmac_prepare(sc);
1999
2000	return (error);
2001}
2002
2003/*
2004 * XXX: this is looutput. We should eventually use it from there.
2005 */
2006static int
2007carp_looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
2008    struct rtentry *rt)
2009{
2010	u_int32_t af;
2011
2012	M_ASSERTPKTHDR(m); /* check if we have the packet header */
2013
2014	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
2015		m_freem(m);
2016		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
2017			rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
2018	}
2019
2020	ifp->if_opackets++;
2021	ifp->if_obytes += m->m_pkthdr.len;
2022
2023	/* BPF writes need to be handled specially. */
2024	if (dst->sa_family == AF_UNSPEC) {
2025		bcopy(dst->sa_data, &af, sizeof(af));
2026		dst->sa_family = af;
2027	}
2028
2029#if 1	/* XXX */
2030	switch (dst->sa_family) {
2031	case AF_INET:
2032	case AF_INET6:
2033	case AF_IPX:
2034	case AF_APPLETALK:
2035		break;
2036	default:
2037		printf("carp_looutput: af=%d unexpected\n", dst->sa_family);
2038		m_freem(m);
2039		return (EAFNOSUPPORT);
2040	}
2041#endif
2042	return(if_simloop(ifp, m, dst->sa_family, 0));
2043}
2044
2045/*
2046 * Start output on carp interface. This function should never be called.
2047 */
2048static void
2049carp_start(struct ifnet *ifp)
2050{
2051#ifdef DEBUG
2052	printf("%s: start called\n", ifp->if_xname);
2053#endif
2054}
2055
2056int
2057carp_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa,
2058    struct rtentry *rt)
2059{
2060	struct m_tag *mtag;
2061	struct carp_softc *sc;
2062	struct ifnet *carp_ifp;
2063
2064	if (!sa)
2065		return (0);
2066
2067	switch (sa->sa_family) {
2068#ifdef INET
2069	case AF_INET:
2070		break;
2071#endif /* INET */
2072#ifdef INET6
2073	case AF_INET6:
2074		break;
2075#endif /* INET6 */
2076	default:
2077		return (0);
2078	}
2079
2080	mtag = m_tag_find(m, PACKET_TAG_CARP, NULL);
2081	if (mtag == NULL)
2082		return (0);
2083
2084	bcopy(mtag + 1, &carp_ifp, sizeof(struct ifnet *));
2085	sc = carp_ifp->if_softc;
2086
2087	/* Set the source MAC address to Virtual Router MAC Address */
2088	switch (ifp->if_type) {
2089	case IFT_ETHER:
2090	case IFT_L2VLAN: {
2091			struct ether_header *eh;
2092
2093			eh = mtod(m, struct ether_header *);
2094			eh->ether_shost[0] = 0;
2095			eh->ether_shost[1] = 0;
2096			eh->ether_shost[2] = 0x5e;
2097			eh->ether_shost[3] = 0;
2098			eh->ether_shost[4] = 1;
2099			eh->ether_shost[5] = sc->sc_vhid;
2100		}
2101		break;
2102	case IFT_FDDI: {
2103			struct fddi_header *fh;
2104
2105			fh = mtod(m, struct fddi_header *);
2106			fh->fddi_shost[0] = 0;
2107			fh->fddi_shost[1] = 0;
2108			fh->fddi_shost[2] = 0x5e;
2109			fh->fddi_shost[3] = 0;
2110			fh->fddi_shost[4] = 1;
2111			fh->fddi_shost[5] = sc->sc_vhid;
2112		}
2113		break;
2114	case IFT_ISO88025: {
2115 			struct iso88025_header *th;
2116 			th = mtod(m, struct iso88025_header *);
2117			th->iso88025_shost[0] = 3;
2118			th->iso88025_shost[1] = 0;
2119			th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1);
2120			th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1);
2121			th->iso88025_shost[4] = 0;
2122			th->iso88025_shost[5] = 0;
2123		}
2124		break;
2125	default:
2126		printf("%s: carp is not supported for this interface type\n",
2127		    ifp->if_xname);
2128		return (EOPNOTSUPP);
2129	}
2130
2131	return (0);
2132}
2133
2134static void
2135carp_set_state(struct carp_softc *sc, int state)
2136{
2137
2138	if (sc->sc_carpdev)
2139		CARP_SCLOCK_ASSERT(sc);
2140
2141	if (sc->sc_state == state)
2142		return;
2143
2144	sc->sc_state = state;
2145	switch (state) {
2146	case BACKUP:
2147		SC2IFP(sc)->if_link_state = LINK_STATE_DOWN;
2148		break;
2149	case MASTER:
2150		SC2IFP(sc)->if_link_state = LINK_STATE_UP;
2151		break;
2152	default:
2153		SC2IFP(sc)->if_link_state = LINK_STATE_UNKNOWN;
2154		break;
2155	}
2156	rt_ifmsg(SC2IFP(sc));
2157}
2158
2159void
2160carp_carpdev_state(void *v)
2161{
2162	struct carp_if *cif = v;
2163
2164	CARP_LOCK(cif);
2165	carp_carpdev_state_locked(cif);
2166	CARP_UNLOCK(cif);
2167}
2168
2169static void
2170carp_carpdev_state_locked(struct carp_if *cif)
2171{
2172	struct carp_softc *sc;
2173
2174	TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list)
2175		carp_sc_state_locked(sc);
2176}
2177
2178static void
2179carp_sc_state_locked(struct carp_softc *sc)
2180{
2181	CARP_SCLOCK_ASSERT(sc);
2182
2183	if (sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
2184	    !(sc->sc_carpdev->if_flags & IFF_UP)) {
2185		sc->sc_flags_backup = SC2IFP(sc)->if_flags;
2186		SC2IFP(sc)->if_flags &= ~IFF_UP;
2187		SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING;
2188		callout_stop(&sc->sc_ad_tmo);
2189		callout_stop(&sc->sc_md_tmo);
2190		callout_stop(&sc->sc_md6_tmo);
2191		carp_set_state(sc, INIT);
2192		carp_setrun(sc, 0);
2193		if (!sc->sc_suppress) {
2194			carp_suppress_preempt++;
2195			if (carp_suppress_preempt == 1) {
2196				CARP_SCUNLOCK(sc);
2197				carp_send_ad_all();
2198				CARP_SCLOCK(sc);
2199			}
2200		}
2201		sc->sc_suppress = 1;
2202	} else {
2203		SC2IFP(sc)->if_flags |= sc->sc_flags_backup;
2204		carp_set_state(sc, INIT);
2205		carp_setrun(sc, 0);
2206		if (sc->sc_suppress)
2207			carp_suppress_preempt--;
2208		sc->sc_suppress = 0;
2209	}
2210
2211	return;
2212}
2213
2214static int
2215carp_modevent(module_t mod, int type, void *data)
2216{
2217	switch (type) {
2218	case MOD_LOAD:
2219		if_detach_event_tag = EVENTHANDLER_REGISTER(ifnet_departure_event,
2220		    carp_ifdetach, NULL, EVENTHANDLER_PRI_ANY);
2221		if (if_detach_event_tag == NULL)
2222			return (ENOMEM);
2223		mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF);
2224		LIST_INIT(&carpif_list);
2225		if_clone_attach(&carp_cloner);
2226		break;
2227
2228	case MOD_UNLOAD:
2229		EVENTHANDLER_DEREGISTER(ifnet_departure_event, if_detach_event_tag);
2230		if_clone_detach(&carp_cloner);
2231		mtx_destroy(&carp_mtx);
2232		break;
2233
2234	default:
2235		return (EINVAL);
2236	}
2237
2238	return (0);
2239}
2240
2241static moduledata_t carp_mod = {
2242	"carp",
2243	carp_modevent,
2244	0
2245};
2246
2247DECLARE_MODULE(carp, carp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
2248