2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2002 Michael Shalayeff.
5 * Copyright (c) 2003 Ryan McBride.
6 * Copyright (c) 2011 Gleb Smirnoff <glebius@FreeBSD.org>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28 * THE POSSIBILITY OF SUCH DAMAGE.
31 #include <sys/cdefs.h>
34 #include "opt_inet6.h"
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/devctl.h>
40 #include <sys/kernel.h>
41 #include <sys/limits.h>
42 #include <sys/malloc.h>
44 #include <sys/module.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/sockio.h>
50 #include <sys/sysctl.h>
51 #include <sys/syslog.h>
52 #include <sys/taskqueue.h>
53 #include <sys/counter.h>
55 #include <net/ethernet.h>
57 #include <net/if_var.h>
58 #include <net/if_dl.h>
59 #include <net/if_llatbl.h>
60 #include <net/if_types.h>
61 #include <net/route.h>
64 #if defined(INET) || defined(INET6)
65 #include <netinet/in.h>
66 #include <netinet/in_var.h>
67 #include <netinet/ip_carp.h>
68 #include <netinet/ip.h>
69 #include <machine/in_cksum.h>
72 #include <netinet/ip_var.h>
73 #include <netinet/if_ether.h>
77 #include <netinet/icmp6.h>
78 #include <netinet/ip6.h>
79 #include <netinet6/in6_var.h>
80 #include <netinet6/ip6_var.h>
81 #include <netinet6/scope6_var.h>
82 #include <netinet6/nd6.h>
85 #include <crypto/sha1.h>
87 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses");
90 struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */
91 struct ifaddr **sc_ifas; /* Our ifaddrs. */
92 struct sockaddr_dl sc_addr; /* Our link level address. */
93 struct callout sc_ad_tmo; /* Advertising timeout. */
95 struct callout sc_md_tmo; /* Master down timeout. */
98 struct callout sc_md6_tmo; /* XXX: Master down timeout. */
109 enum { INIT = 0, BACKUP, MASTER } sc_state;
111 int sc_sendad_errors;
112 #define CARP_SENDAD_MAX_ERRORS 3
113 int sc_sendad_success;
114 #define CARP_SENDAD_MIN_SUCCESS 3
120 #define CARP_HMAC_PAD 64
121 unsigned char sc_key[CARP_KEY_LEN];
122 unsigned char sc_pad[CARP_HMAC_PAD];
125 TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */
126 LIST_ENTRY(carp_softc) sc_next; /* On the global list. */
136 TAILQ_HEAD(, carp_softc) cif_vrs;
138 struct ip_moptions cif_imo;
141 struct ip6_moptions cif_im6o;
143 struct ifnet *cif_ifp;
146 #define CIF_PROMISC 0x00000001
151 static int proto_reg[] = {-1, -1};
154 * Brief design of carp(4).
156 * Any carp-capable ifnet may have a list of carp softcs hanging off
157 * its ifp->if_carp pointer. Each softc represents one unique virtual
158 * host id, or vhid. The softc has a back pointer to the ifnet. All
159 * softcs are joined in a global list, which has quite limited use.
161 * Any interface address that takes part in CARP negotiation has a
162 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either
163 * AF_INET or AF_INET6 address.
165 * Although, one can get the softc's backpointer to ifnet and traverse
166 * through its ifp->if_addrhead queue to find all interface addresses
167 * involved in CARP, we keep a growable array of ifaddr pointers. This
168 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that
169 * do calls into the network stack, thus avoiding LORs.
173 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(),
174 * callout-driven events and ioctl()s.
176 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx.
177 * To traverse the global list we use the mutex carp_mtx.
179 * Known issues with locking:
181 * - Sending ad, we put the pointer to the softc in an mtag, and no reference
182 * counting is done on the softc.
183 * - On module unload we may race (?) with packet processing thread
184 * dereferencing our function pointers.
187 /* Accept incoming CARP packets. */
188 VNET_DEFINE_STATIC(int, carp_allow) = 1;
189 #define V_carp_allow VNET(carp_allow)
191 /* Set DSCP in outgoing CARP packets. */
192 VNET_DEFINE_STATIC(int, carp_dscp) = 56;
193 #define V_carp_dscp VNET(carp_dscp)
195 /* Preempt slower nodes. */
196 VNET_DEFINE_STATIC(int, carp_preempt) = 0;
197 #define V_carp_preempt VNET(carp_preempt)
200 VNET_DEFINE_STATIC(int, carp_log) = 1;
201 #define V_carp_log VNET(carp_log)
203 /* Global advskew demotion. */
204 VNET_DEFINE_STATIC(int, carp_demotion) = 0;
205 #define V_carp_demotion VNET(carp_demotion)
207 /* Send error demotion factor. */
208 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW;
209 #define V_carp_senderr_adj VNET(carp_senderr_adj)
211 /* Iface down demotion factor. */
212 VNET_DEFINE_STATIC(int, carp_ifdown_adj) = CARP_MAXSKEW;
213 #define V_carp_ifdown_adj VNET(carp_ifdown_adj)
215 static int carp_allow_sysctl(SYSCTL_HANDLER_ARGS);
216 static int carp_dscp_sysctl(SYSCTL_HANDLER_ARGS);
217 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS);
219 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
221 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow,
222 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE,
223 &VNET_NAME(carp_allow), 0, carp_allow_sysctl, "I",
224 "Accept incoming CARP packets");
225 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp,
226 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
227 0, 0, carp_dscp_sysctl, "I",
228 "DSCP value for carp packets");
229 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW,
230 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode");
231 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW,
232 &VNET_NAME(carp_log), 0, "CARP log level");
233 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion,
234 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
235 0, 0, carp_demote_adj_sysctl, "I",
236 "Adjust demotion factor (skew of advskew)");
237 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor,
238 CTLFLAG_VNET | CTLFLAG_RW,
239 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment");
240 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor,
241 CTLFLAG_VNET | CTLFLAG_RW,
242 &VNET_NAME(carp_ifdown_adj), 0,
243 "Interface down demotion factor adjustment");
245 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats);
246 VNET_PCPUSTAT_SYSINIT(carpstats);
247 VNET_PCPUSTAT_SYSUNINIT(carpstats);
249 #define CARPSTATS_ADD(name, val) \
250 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \
251 sizeof(uint64_t)], (val))
252 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1)
254 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats,
255 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)");
257 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \
259 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx)
260 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED)
261 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx)
262 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx)
263 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \
265 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx)
266 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED)
267 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx)
268 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx)
269 #define CIF_FREE(cif) do { \
271 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \
277 #define CARP_LOG(...) do { \
278 if (V_carp_log > 0) \
279 log(LOG_INFO, "carp: " __VA_ARGS__); \
282 #define CARP_DEBUG(...) do { \
283 if (V_carp_log > 1) \
284 log(LOG_DEBUG, __VA_ARGS__); \
287 #define IFNET_FOREACH_IFA(ifp, ifa) \
288 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \
289 if ((ifa)->ifa_carp != NULL)
291 #define CARP_FOREACH_IFA(sc, ifa) \
292 CARP_LOCK_ASSERT(sc); \
294 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \
295 ((ifa) = sc->sc_ifas[_i]) != NULL; \
298 #define IFNET_FOREACH_CARP(ifp, sc) \
299 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \
300 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \
301 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list)
303 #define DEMOTE_ADVSKEW(sc) \
304 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \
306 (((sc)->sc_advskew + V_carp_demotion < 0) ? \
307 0 : ((sc)->sc_advskew + V_carp_demotion)))
309 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t);
310 static struct carp_softc
311 *carp_alloc(struct ifnet *);
312 static void carp_destroy(struct carp_softc *);
313 static struct carp_if
314 *carp_alloc_if(struct ifnet *);
315 static void carp_free_if(struct carp_if *);
316 static void carp_set_state(struct carp_softc *, int, const char* reason);
317 static void carp_sc_state(struct carp_softc *);
318 static void carp_setrun(struct carp_softc *, sa_family_t);
319 static void carp_master_down(void *);
320 static void carp_master_down_locked(struct carp_softc *,
322 static void carp_send_ad(void *);
323 static void carp_send_ad_locked(struct carp_softc *);
324 static void carp_addroute(struct carp_softc *);
325 static void carp_ifa_addroute(struct ifaddr *);
326 static void carp_delroute(struct carp_softc *);
327 static void carp_ifa_delroute(struct ifaddr *);
328 static void carp_send_ad_all(void *, int);
329 static void carp_demote_adj(int, char *);
331 static LIST_HEAD(, carp_softc) carp_list;
332 static struct mtx carp_mtx;
333 static struct sx carp_sx;
334 static struct task carp_sendall_task =
335 TASK_INITIALIZER(0, carp_send_ad_all, NULL);
338 carp_hmac_prepare(struct carp_softc *sc)
340 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
341 uint8_t vhid = sc->sc_vhid & 0xff;
345 struct in_addr last, cur, in;
348 struct in6_addr last6, cur6, in6;
351 CARP_LOCK_ASSERT(sc);
353 /* Compute ipad from key. */
354 bzero(sc->sc_pad, sizeof(sc->sc_pad));
355 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key));
356 for (i = 0; i < sizeof(sc->sc_pad); i++)
357 sc->sc_pad[i] ^= 0x36;
359 /* Precompute first part of inner hash. */
360 SHA1Init(&sc->sc_sha1);
361 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
362 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version));
363 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
364 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
370 cur.s_addr = 0xffffffff;
371 CARP_FOREACH_IFA(sc, ifa) {
372 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr;
373 if (ifa->ifa_addr->sa_family == AF_INET &&
374 ntohl(in.s_addr) > ntohl(last.s_addr) &&
375 ntohl(in.s_addr) < ntohl(cur.s_addr)) {
376 cur.s_addr = in.s_addr;
381 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur));
385 memset(&cur6, 0, sizeof(cur6));
389 memset(&cur6, 0xff, sizeof(cur6));
390 CARP_FOREACH_IFA(sc, ifa) {
391 in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
392 if (IN6_IS_SCOPE_EMBED(&in6))
393 in6.s6_addr16[1] = 0;
394 if (ifa->ifa_addr->sa_family == AF_INET6 &&
395 memcmp(&in6, &last6, sizeof(in6)) > 0 &&
396 memcmp(&in6, &cur6, sizeof(in6)) < 0) {
402 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6));
406 /* convert ipad to opad */
407 for (i = 0; i < sizeof(sc->sc_pad); i++)
408 sc->sc_pad[i] ^= 0x36 ^ 0x5c;
412 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2],
413 unsigned char md[20])
417 CARP_LOCK_ASSERT(sc);
419 /* fetch first half of inner hash */
420 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx));
422 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
423 SHA1Final(md, &sha1ctx);
427 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
428 SHA1Update(&sha1ctx, md, 20);
429 SHA1Final(md, &sha1ctx);
433 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2],
434 unsigned char md[20])
436 unsigned char md2[20];
438 CARP_LOCK_ASSERT(sc);
440 carp_hmac_generate(sc, counter, md2);
442 return (bcmp(md, md2, sizeof(md2)));
446 * process input packet.
447 * we have rearranged checks order compared to the rfc,
448 * but it seems more efficient this way or not possible otherwise.
452 carp_input(struct mbuf **mp, int *offp, int proto)
454 struct mbuf *m = *mp;
455 struct ip *ip = mtod(m, struct ip *);
456 struct carp_header *ch;
462 CARPSTATS_INC(carps_ipackets);
466 return (IPPROTO_DONE);
469 /* verify that the IP TTL is 255. */
470 if (ip->ip_ttl != CARP_DFLTTL) {
471 CARPSTATS_INC(carps_badttl);
472 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
474 m->m_pkthdr.rcvif->if_xname);
476 return (IPPROTO_DONE);
479 iplen = ip->ip_hl << 2;
481 if (m->m_pkthdr.len < iplen + sizeof(*ch)) {
482 CARPSTATS_INC(carps_badlen);
483 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) "
484 "on %s\n", __func__, m->m_len - sizeof(struct ip),
485 m->m_pkthdr.rcvif->if_xname);
487 return (IPPROTO_DONE);
490 if (iplen + sizeof(*ch) < m->m_len) {
491 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) {
492 CARPSTATS_INC(carps_hdrops);
493 CARP_DEBUG("%s: pullup failed\n", __func__);
494 return (IPPROTO_DONE);
496 ip = mtod(m, struct ip *);
498 ch = (struct carp_header *)((char *)ip + iplen);
501 * verify that the received packet length is
502 * equal to the CARP header
504 len = iplen + sizeof(*ch);
505 if (len > m->m_pkthdr.len) {
506 CARPSTATS_INC(carps_badlen);
507 CARP_DEBUG("%s: packet too short %d on %s\n", __func__,
509 m->m_pkthdr.rcvif->if_xname);
511 return (IPPROTO_DONE);
514 if ((m = m_pullup(m, len)) == NULL) {
515 CARPSTATS_INC(carps_hdrops);
516 return (IPPROTO_DONE);
518 ip = mtod(m, struct ip *);
519 ch = (struct carp_header *)((char *)ip + iplen);
521 /* verify the CARP checksum */
523 if (in_cksum(m, len - iplen)) {
524 CARPSTATS_INC(carps_badsum);
525 CARP_DEBUG("%s: checksum failed on %s\n", __func__,
526 m->m_pkthdr.rcvif->if_xname);
528 return (IPPROTO_DONE);
532 carp_input_c(m, ch, AF_INET);
533 return (IPPROTO_DONE);
539 carp6_input(struct mbuf **mp, int *offp, int proto)
541 struct mbuf *m = *mp;
542 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
543 struct carp_header *ch;
546 CARPSTATS_INC(carps_ipackets6);
550 return (IPPROTO_DONE);
553 /* check if received on a valid carp interface */
554 if (m->m_pkthdr.rcvif->if_carp == NULL) {
555 CARPSTATS_INC(carps_badif);
556 CARP_DEBUG("%s: packet received on non-carp interface: %s\n",
557 __func__, m->m_pkthdr.rcvif->if_xname);
559 return (IPPROTO_DONE);
562 /* verify that the IP TTL is 255 */
563 if (ip6->ip6_hlim != CARP_DFLTTL) {
564 CARPSTATS_INC(carps_badttl);
565 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
566 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname);
568 return (IPPROTO_DONE);
571 /* verify that we have a complete carp packet */
572 if (m->m_len < *offp + sizeof(*ch)) {
574 m = m_pullup(m, *offp + sizeof(*ch));
576 CARPSTATS_INC(carps_badlen);
577 CARP_DEBUG("%s: packet size %u too small\n", __func__, len);
578 return (IPPROTO_DONE);
581 ch = (struct carp_header *)(mtod(m, char *) + *offp);
583 /* verify the CARP checksum */
585 if (in_cksum(m, sizeof(*ch))) {
586 CARPSTATS_INC(carps_badsum);
587 CARP_DEBUG("%s: checksum failed, on %s\n", __func__,
588 m->m_pkthdr.rcvif->if_xname);
590 return (IPPROTO_DONE);
594 carp_input_c(m, ch, AF_INET6);
595 return (IPPROTO_DONE);
600 * This routine should not be necessary at all, but some switches
601 * (VMWare ESX vswitches) can echo our own packets back at us,
602 * and we must ignore them or they will cause us to drop out of
605 * We cannot catch all cases of network loops. Instead, what we
606 * do here is catch any packet that arrives with a carp header
607 * with a VHID of 0, that comes from an address that is our own.
608 * These packets are by definition "from us" (even if they are from
609 * a misconfigured host that is pretending to be us).
611 * The VHID test is outside this mini-function.
614 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af)
628 ip4 = mtod(m, struct ip *);
629 in4 = ifatoia(ifa)->ia_addr.sin_addr;
630 return (in4.s_addr == ip4->ip_src.s_addr);
634 ip6 = mtod(m, struct ip6_hdr *);
635 in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
636 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0);
645 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
647 struct ifnet *ifp = m->m_pkthdr.rcvif;
648 struct ifaddr *ifa, *match;
649 struct carp_softc *sc;
650 uint64_t tmp_counter;
651 struct timeval sc_tv, ch_tv;
657 * Verify that the VHID is valid on the receiving interface.
659 * There should be just one match. If there are none
660 * the VHID is not valid and we drop the packet. If
661 * there are multiple VHID matches, take just the first
662 * one, for compatibility with previous code. While we're
663 * scanning, check for obvious loops in the network topology
664 * (these should never happen, and as noted above, we may
665 * miss real loops; this is just a double-check).
669 IFNET_FOREACH_IFA(ifp, ifa) {
670 if (match == NULL && ifa->ifa_carp != NULL &&
671 ifa->ifa_addr->sa_family == af &&
672 ifa->ifa_carp->sc_vhid == ch->carp_vhid)
674 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af))
677 ifa = error ? NULL : match;
682 if (error == ELOOP) {
683 CARP_DEBUG("dropping looped packet on interface %s\n",
685 CARPSTATS_INC(carps_badif); /* ??? */
687 CARPSTATS_INC(carps_badvhid);
693 /* verify the CARP version. */
694 if (ch->carp_version != CARP_VERSION) {
695 CARPSTATS_INC(carps_badver);
696 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname,
707 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
708 CARPSTATS_INC(carps_badauth);
709 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__,
710 sc->sc_vhid, ifp->if_xname);
714 tmp_counter = ntohl(ch->carp_counter[0]);
715 tmp_counter = tmp_counter<<32;
716 tmp_counter += ntohl(ch->carp_counter[1]);
718 /* XXX Replay protection goes here */
720 sc->sc_init_counter = 0;
721 sc->sc_counter = tmp_counter;
723 sc_tv.tv_sec = sc->sc_advbase;
724 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256;
725 ch_tv.tv_sec = ch->carp_advbase;
726 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
728 switch (sc->sc_state) {
733 * If we receive an advertisement from a master who's going to
734 * be more frequent than us, go into BACKUP state.
736 if (timevalcmp(&sc_tv, &ch_tv, >) ||
737 timevalcmp(&sc_tv, &ch_tv, ==)) {
738 callout_stop(&sc->sc_ad_tmo);
739 carp_set_state(sc, BACKUP,
740 "more frequent advertisement received");
747 * If we're pre-empting masters who advertise slower than us,
748 * and this one claims to be slower, treat him as down.
750 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) {
751 carp_master_down_locked(sc,
752 "preempting a slower master");
757 * If the master is going to advertise at such a low frequency
758 * that he's guaranteed to time out, we'd might as well just
759 * treat him as timed out now.
761 sc_tv.tv_sec = sc->sc_advbase * 3;
762 if (timevalcmp(&sc_tv, &ch_tv, <)) {
763 carp_master_down_locked(sc, "master will time out");
768 * Otherwise, we reset the counter and wait for the next
781 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch)
785 if (sc->sc_init_counter) {
786 /* this could also be seconds since unix epoch */
787 sc->sc_counter = arc4random();
788 sc->sc_counter = sc->sc_counter << 32;
789 sc->sc_counter += arc4random();
793 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
794 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
796 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
798 /* Tag packet for carp_output */
799 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *),
800 M_NOWAIT)) == NULL) {
802 CARPSTATS_INC(carps_onomem);
805 bcopy(&sc, mtag + 1, sizeof(sc));
806 m_tag_prepend(m, mtag);
812 * To avoid LORs and possible recursions this function shouldn't
813 * be called directly, but scheduled via taskqueue.
816 carp_send_ad_all(void *ctx __unused, int pending __unused)
818 struct carp_softc *sc;
819 struct epoch_tracker et;
823 LIST_FOREACH(sc, &carp_list, sc_next)
824 if (sc->sc_state == MASTER) {
826 CURVNET_SET(sc->sc_carpdev->if_vnet);
827 carp_send_ad_locked(sc);
831 mtx_unlock(&carp_mtx);
835 /* Send a periodic advertisement, executed in callout context. */
837 carp_send_ad(void *v)
839 struct carp_softc *sc = v;
840 struct epoch_tracker et;
843 CARP_LOCK_ASSERT(sc);
844 CURVNET_SET(sc->sc_carpdev->if_vnet);
845 carp_send_ad_locked(sc);
852 carp_send_ad_error(struct carp_softc *sc, int error)
856 * We track errors and successfull sends with this logic:
857 * - Any error resets success counter to 0.
858 * - MAX_ERRORS triggers demotion.
859 * - MIN_SUCCESS successes resets error counter to 0.
860 * - MIN_SUCCESS reverts demotion, if it was triggered before.
863 if (sc->sc_sendad_errors < INT_MAX)
864 sc->sc_sendad_errors++;
865 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
866 static const char fmt[] = "send error %d on %s";
867 char msg[sizeof(fmt) + IFNAMSIZ];
869 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname);
870 carp_demote_adj(V_carp_senderr_adj, msg);
872 sc->sc_sendad_success = 0;
873 } else if (sc->sc_sendad_errors > 0) {
874 if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) {
875 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) {
876 static const char fmt[] = "send ok on %s";
877 char msg[sizeof(fmt) + IFNAMSIZ];
879 sprintf(msg, fmt, sc->sc_carpdev->if_xname);
880 carp_demote_adj(-V_carp_senderr_adj, msg);
882 sc->sc_sendad_errors = 0;
888 * Pick the best ifaddr on the given ifp for sending CARP
891 * "Best" here is defined by ifa_preferred(). This function is much
892 * much like ifaof_ifpforaddr() except that we just use ifa_preferred().
894 * (This could be simplified to return the actual address, except that
895 * it has a different format in AF_INET and AF_INET6.)
897 static struct ifaddr *
898 carp_best_ifa(int af, struct ifnet *ifp)
900 struct ifaddr *ifa, *best;
907 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
908 if (ifa->ifa_addr->sa_family == af &&
909 (best == NULL || ifa_preferred(best, ifa)))
918 carp_send_ad_locked(struct carp_softc *sc)
920 struct carp_header ch;
923 struct carp_header *ch_ptr;
928 CARP_LOCK_ASSERT(sc);
930 advskew = DEMOTE_ADVSKEW(sc);
931 tv.tv_sec = sc->sc_advbase;
932 tv.tv_usec = advskew * 1000000 / 256;
934 ch.carp_version = CARP_VERSION;
935 ch.carp_type = CARP_ADVERTISEMENT;
936 ch.carp_vhid = sc->sc_vhid;
937 ch.carp_advbase = sc->sc_advbase;
938 ch.carp_advskew = advskew;
939 ch.carp_authlen = 7; /* XXX DEFINE */
940 ch.carp_pad1 = 0; /* must be zero */
943 /* XXXGL: OpenBSD picks first ifaddr with needed family. */
949 m = m_gethdr(M_NOWAIT, MT_DATA);
951 CARPSTATS_INC(carps_onomem);
954 len = sizeof(*ip) + sizeof(ch);
955 m->m_pkthdr.len = len;
956 m->m_pkthdr.rcvif = NULL;
958 M_ALIGN(m, m->m_len);
959 m->m_flags |= M_MCAST;
960 ip = mtod(m, struct ip *);
961 ip->ip_v = IPVERSION;
962 ip->ip_hl = sizeof(*ip) >> 2;
963 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET;
964 ip->ip_len = htons(len);
965 ip->ip_off = htons(IP_DF);
966 ip->ip_ttl = CARP_DFLTTL;
967 ip->ip_p = IPPROTO_CARP;
971 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev);
974 ifatoia(ifa)->ia_addr.sin_addr.s_addr;
977 ip->ip_src.s_addr = 0;
978 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP);
980 ch_ptr = (struct carp_header *)(&ip[1]);
981 bcopy(&ch, ch_ptr, sizeof(ch));
982 if (carp_prepare_ad(m, sc, ch_ptr))
985 m->m_data += sizeof(*ip);
986 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip));
987 m->m_data -= sizeof(*ip);
989 CARPSTATS_INC(carps_opackets);
991 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT,
992 &sc->sc_carpdev->if_carp->cif_imo, NULL));
996 if (sc->sc_naddrs6) {
999 m = m_gethdr(M_NOWAIT, MT_DATA);
1001 CARPSTATS_INC(carps_onomem);
1004 len = sizeof(*ip6) + sizeof(ch);
1005 m->m_pkthdr.len = len;
1006 m->m_pkthdr.rcvif = NULL;
1008 M_ALIGN(m, m->m_len);
1009 m->m_flags |= M_MCAST;
1010 ip6 = mtod(m, struct ip6_hdr *);
1011 bzero(ip6, sizeof(*ip6));
1012 ip6->ip6_vfc |= IPV6_VERSION;
1013 /* Traffic class isn't defined in ip6 struct instead
1014 * it gets offset into flowid field */
1015 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN +
1016 IPTOS_DSCP_OFFSET));
1017 ip6->ip6_hlim = CARP_DFLTTL;
1018 ip6->ip6_nxt = IPPROTO_CARP;
1020 /* set the source address */
1021 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev);
1023 bcopy(IFA_IN6(ifa), &ip6->ip6_src,
1024 sizeof(struct in6_addr));
1027 /* This should never happen with IPv6. */
1028 bzero(&ip6->ip6_src, sizeof(struct in6_addr));
1030 /* Set the multicast destination. */
1031 ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
1032 ip6->ip6_dst.s6_addr8[15] = 0x12;
1033 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) {
1035 CARP_DEBUG("%s: in6_setscope failed\n", __func__);
1039 ch_ptr = (struct carp_header *)(&ip6[1]);
1040 bcopy(&ch, ch_ptr, sizeof(ch));
1041 if (carp_prepare_ad(m, sc, ch_ptr))
1044 m->m_data += sizeof(*ip6);
1045 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6));
1046 m->m_data -= sizeof(*ip6);
1048 CARPSTATS_INC(carps_opackets6);
1050 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0,
1051 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL));
1056 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc);
1060 carp_addroute(struct carp_softc *sc)
1064 CARP_FOREACH_IFA(sc, ifa)
1065 carp_ifa_addroute(ifa);
1069 carp_ifa_addroute(struct ifaddr *ifa)
1072 switch (ifa->ifa_addr->sa_family) {
1075 in_addprefix(ifatoia(ifa));
1076 ifa_add_loopback_route(ifa,
1077 (struct sockaddr *)&ifatoia(ifa)->ia_addr);
1082 ifa_add_loopback_route(ifa,
1083 (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
1084 nd6_add_ifa_lle(ifatoia6(ifa));
1091 carp_delroute(struct carp_softc *sc)
1095 CARP_FOREACH_IFA(sc, ifa)
1096 carp_ifa_delroute(ifa);
1100 carp_ifa_delroute(struct ifaddr *ifa)
1103 switch (ifa->ifa_addr->sa_family) {
1106 ifa_del_loopback_route(ifa,
1107 (struct sockaddr *)&ifatoia(ifa)->ia_addr);
1108 in_scrubprefix(ifatoia(ifa), LLE_STATIC);
1113 ifa_del_loopback_route(ifa,
1114 (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
1115 nd6_rem_ifa_lle(ifatoia6(ifa), 1);
1122 carp_master(struct ifaddr *ifa)
1124 struct carp_softc *sc = ifa->ifa_carp;
1126 return (sc->sc_state == MASTER);
1131 * Broadcast a gratuitous ARP request containing
1132 * the virtual router MAC address for each IP address
1133 * associated with the virtual router.
1136 carp_send_arp(struct carp_softc *sc)
1139 struct in_addr addr;
1143 CARP_FOREACH_IFA(sc, ifa) {
1144 if (ifa->ifa_addr->sa_family != AF_INET)
1146 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
1147 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr));
1152 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr)
1154 struct carp_softc *sc = ifa->ifa_carp;
1156 if (sc->sc_state == MASTER) {
1157 *enaddr = LLADDR(&sc->sc_addr);
1167 carp_send_na(struct carp_softc *sc)
1169 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
1171 struct in6_addr *in6;
1173 CARP_FOREACH_IFA(sc, ifa) {
1174 if (ifa->ifa_addr->sa_family != AF_INET6)
1178 nd6_na_output(sc->sc_carpdev, &mcast, in6,
1179 ND_NA_FLAG_OVERRIDE, 1, NULL);
1180 DELAY(1000); /* XXX */
1185 * Returns ifa in case it's a carp address and it is MASTER, or if the address
1186 * matches and is not a carp address. Returns NULL otherwise.
1189 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr)
1196 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1197 if (ifa->ifa_addr->sa_family != AF_INET6)
1199 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa)))
1201 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER)
1212 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr)
1218 IFNET_FOREACH_IFA(ifp, ifa)
1219 if (ifa->ifa_addr->sa_family == AF_INET6 &&
1220 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) {
1221 struct carp_softc *sc = ifa->ifa_carp;
1224 mtag = m_tag_get(PACKET_TAG_CARP,
1225 sizeof(struct carp_softc *), M_NOWAIT);
1227 /* Better a bit than nothing. */
1228 return (LLADDR(&sc->sc_addr));
1230 bcopy(&sc, mtag + 1, sizeof(sc));
1231 m_tag_prepend(m, mtag);
1233 return (LLADDR(&sc->sc_addr));
1241 carp_forus(struct ifnet *ifp, u_char *dhost)
1243 struct carp_softc *sc;
1244 uint8_t *ena = dhost;
1246 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
1249 CIF_LOCK(ifp->if_carp);
1250 IFNET_FOREACH_CARP(ifp, sc) {
1252 * CARP_LOCK() is not here, since would protect nothing, but
1253 * cause deadlock with if_bridge, calling this under its lock.
1255 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr),
1257 CIF_UNLOCK(ifp->if_carp);
1261 CIF_UNLOCK(ifp->if_carp);
1266 /* Master down timeout event, executed in callout context. */
1268 carp_master_down(void *v)
1270 struct carp_softc *sc = v;
1271 struct epoch_tracker et;
1273 NET_EPOCH_ENTER(et);
1274 CARP_LOCK_ASSERT(sc);
1276 CURVNET_SET(sc->sc_carpdev->if_vnet);
1277 if (sc->sc_state == BACKUP) {
1278 carp_master_down_locked(sc, "master timed out");
1287 carp_master_down_locked(struct carp_softc *sc, const char *reason)
1291 CARP_LOCK_ASSERT(sc);
1293 switch (sc->sc_state) {
1295 carp_set_state(sc, MASTER, reason);
1296 carp_send_ad_locked(sc);
1309 panic("carp: VHID %u@%s: master_down event in %s state\n",
1311 sc->sc_carpdev->if_xname,
1312 sc->sc_state ? "MASTER" : "INIT");
1319 * When in backup state, af indicates whether to reset the master down timer
1320 * for v4 or v6. If it's set to zero, reset the ones which are already pending.
1323 carp_setrun(struct carp_softc *sc, sa_family_t af)
1327 CARP_LOCK_ASSERT(sc);
1329 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 ||
1330 sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
1331 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) ||
1335 switch (sc->sc_state) {
1337 carp_set_state(sc, BACKUP, "initialization complete");
1341 callout_stop(&sc->sc_ad_tmo);
1342 tv.tv_sec = 3 * sc->sc_advbase;
1343 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1347 callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1348 carp_master_down, sc);
1353 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1354 carp_master_down, sc);
1360 callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1361 carp_master_down, sc);
1365 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1366 carp_master_down, sc);
1372 tv.tv_sec = sc->sc_advbase;
1373 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1374 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
1381 * Setup multicast structures.
1384 carp_multicast_setup(struct carp_if *cif, sa_family_t sa)
1386 struct ifnet *ifp = cif->cif_ifp;
1393 struct ip_moptions *imo = &cif->cif_imo;
1394 struct in_mfilter *imf;
1395 struct in_addr addr;
1397 if (ip_mfilter_first(&imo->imo_head) != NULL)
1400 imf = ip_mfilter_alloc(M_WAITOK, 0, 0);
1401 ip_mfilter_init(&imo->imo_head);
1402 imo->imo_multicast_vif = -1;
1404 addr.s_addr = htonl(INADDR_CARP_GROUP);
1405 if ((error = in_joingroup(ifp, &addr, NULL,
1406 &imf->imf_inm)) != 0) {
1407 ip_mfilter_free(imf);
1411 ip_mfilter_insert(&imo->imo_head, imf);
1412 imo->imo_multicast_ifp = ifp;
1413 imo->imo_multicast_ttl = CARP_DFLTTL;
1414 imo->imo_multicast_loop = 0;
1421 struct ip6_moptions *im6o = &cif->cif_im6o;
1422 struct in6_mfilter *im6f[2];
1423 struct in6_addr in6;
1425 if (ip6_mfilter_first(&im6o->im6o_head))
1428 im6f[0] = ip6_mfilter_alloc(M_WAITOK, 0, 0);
1429 im6f[1] = ip6_mfilter_alloc(M_WAITOK, 0, 0);
1431 ip6_mfilter_init(&im6o->im6o_head);
1432 im6o->im6o_multicast_hlim = CARP_DFLTTL;
1433 im6o->im6o_multicast_ifp = ifp;
1435 /* Join IPv6 CARP multicast group. */
1436 bzero(&in6, sizeof(in6));
1437 in6.s6_addr16[0] = htons(0xff02);
1438 in6.s6_addr8[15] = 0x12;
1439 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
1440 ip6_mfilter_free(im6f[0]);
1441 ip6_mfilter_free(im6f[1]);
1444 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[0]->im6f_in6m, 0)) != 0) {
1445 ip6_mfilter_free(im6f[0]);
1446 ip6_mfilter_free(im6f[1]);
1450 /* Join solicited multicast address. */
1451 bzero(&in6, sizeof(in6));
1452 in6.s6_addr16[0] = htons(0xff02);
1453 in6.s6_addr32[1] = 0;
1454 in6.s6_addr32[2] = htonl(1);
1455 in6.s6_addr32[3] = 0;
1456 in6.s6_addr8[12] = 0xff;
1458 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
1459 ip6_mfilter_free(im6f[0]);
1460 ip6_mfilter_free(im6f[1]);
1464 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[1]->im6f_in6m, 0)) != 0) {
1465 in6_leavegroup(im6f[0]->im6f_in6m, NULL);
1466 ip6_mfilter_free(im6f[0]);
1467 ip6_mfilter_free(im6f[1]);
1470 ip6_mfilter_insert(&im6o->im6o_head, im6f[0]);
1471 ip6_mfilter_insert(&im6o->im6o_head, im6f[1]);
1481 * Free multicast structures.
1484 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa)
1487 struct ip_moptions *imo = &cif->cif_imo;
1488 struct in_mfilter *imf;
1491 struct ip6_moptions *im6o = &cif->cif_im6o;
1492 struct in6_mfilter *im6f;
1494 sx_assert(&carp_sx, SA_XLOCKED);
1499 if (cif->cif_naddrs != 0)
1502 while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) {
1503 ip_mfilter_remove(&imo->imo_head, imf);
1504 in_leavegroup(imf->imf_inm, NULL);
1505 ip_mfilter_free(imf);
1511 if (cif->cif_naddrs6 != 0)
1514 while ((im6f = ip6_mfilter_first(&im6o->im6o_head)) != NULL) {
1515 ip6_mfilter_remove(&im6o->im6o_head, im6f);
1516 in6_leavegroup(im6f->im6f_in6m, NULL);
1517 ip6_mfilter_free(im6f);
1525 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa)
1528 struct carp_softc *sc;
1533 switch (sa->sa_family) {
1546 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL);
1550 bcopy(mtag + 1, &sc, sizeof(sc));
1552 /* Set the source MAC address to the Virtual Router MAC Address. */
1553 switch (ifp->if_type) {
1557 struct ether_header *eh;
1559 eh = mtod(m, struct ether_header *);
1560 eh->ether_shost[0] = 0;
1561 eh->ether_shost[1] = 0;
1562 eh->ether_shost[2] = 0x5e;
1563 eh->ether_shost[3] = 0;
1564 eh->ether_shost[4] = 1;
1565 eh->ether_shost[5] = sc->sc_vhid;
1569 printf("%s: carp is not supported for the %d interface type\n",
1570 ifp->if_xname, ifp->if_type);
1571 return (EOPNOTSUPP);
1577 static struct carp_softc*
1578 carp_alloc(struct ifnet *ifp)
1580 struct carp_softc *sc;
1581 struct carp_if *cif;
1583 sx_assert(&carp_sx, SA_XLOCKED);
1585 if ((cif = ifp->if_carp) == NULL)
1586 cif = carp_alloc_if(ifp);
1588 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO);
1590 sc->sc_advbase = CARP_DFLTINTV;
1591 sc->sc_vhid = -1; /* required setting */
1592 sc->sc_init_counter = 1;
1593 sc->sc_state = INIT;
1595 sc->sc_ifasiz = sizeof(struct ifaddr *);
1596 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO);
1597 sc->sc_carpdev = ifp;
1601 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1604 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1606 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1609 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list);
1612 mtx_lock(&carp_mtx);
1613 LIST_INSERT_HEAD(&carp_list, sc, sc_next);
1614 mtx_unlock(&carp_mtx);
1620 carp_grow_ifas(struct carp_softc *sc)
1622 struct ifaddr **new;
1624 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO);
1626 bcopy(sc->sc_ifas, new, sc->sc_ifasiz);
1627 free(sc->sc_ifas, M_CARP);
1634 carp_destroy(struct carp_softc *sc)
1636 struct ifnet *ifp = sc->sc_carpdev;
1637 struct carp_if *cif = ifp->if_carp;
1639 sx_assert(&carp_sx, SA_XLOCKED);
1641 if (sc->sc_suppress)
1642 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed");
1646 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list);
1649 mtx_lock(&carp_mtx);
1650 LIST_REMOVE(sc, sc_next);
1651 mtx_unlock(&carp_mtx);
1653 callout_drain(&sc->sc_ad_tmo);
1655 callout_drain(&sc->sc_md_tmo);
1658 callout_drain(&sc->sc_md6_tmo);
1660 CARP_LOCK_DESTROY(sc);
1662 free(sc->sc_ifas, M_CARP);
1666 static struct carp_if*
1667 carp_alloc_if(struct ifnet *ifp)
1669 struct carp_if *cif;
1672 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO);
1674 if ((error = ifpromisc(ifp, 1)) != 0)
1675 printf("%s: ifpromisc(%s) failed: %d\n",
1676 __func__, ifp->if_xname, error);
1678 cif->cif_flags |= CIF_PROMISC;
1682 TAILQ_INIT(&cif->cif_vrs);
1687 IF_ADDR_WUNLOCK(ifp);
1693 carp_free_if(struct carp_if *cif)
1695 struct ifnet *ifp = cif->cif_ifp;
1697 CIF_LOCK_ASSERT(cif);
1698 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty",
1702 ifp->if_carp = NULL;
1703 IF_ADDR_WUNLOCK(ifp);
1705 CIF_LOCK_DESTROY(cif);
1707 if (cif->cif_flags & CIF_PROMISC)
1715 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv)
1719 carpr->carpr_state = sc->sc_state;
1720 carpr->carpr_vhid = sc->sc_vhid;
1721 carpr->carpr_advbase = sc->sc_advbase;
1722 carpr->carpr_advskew = sc->sc_advskew;
1724 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key));
1726 bzero(carpr->carpr_key, sizeof(carpr->carpr_key));
1731 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td)
1733 struct epoch_tracker et;
1734 struct carpreq carpr;
1736 struct carp_softc *sc = NULL;
1737 int error = 0, locked = 0;
1739 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr)))
1742 ifp = ifunit_ref(ifr->ifr_name);
1746 switch (ifp->if_type) {
1756 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
1757 error = EADDRNOTAVAIL;
1764 if ((error = priv_check(td, PRIV_NETINET_CARP)))
1766 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID ||
1767 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) {
1773 IFNET_FOREACH_CARP(ifp, sc)
1774 if (sc->sc_vhid == carpr.carpr_vhid)
1778 sc = carp_alloc(ifp);
1780 sc->sc_vhid = carpr.carpr_vhid;
1781 LLADDR(&sc->sc_addr)[0] = 0;
1782 LLADDR(&sc->sc_addr)[1] = 0;
1783 LLADDR(&sc->sc_addr)[2] = 0x5e;
1784 LLADDR(&sc->sc_addr)[3] = 0;
1785 LLADDR(&sc->sc_addr)[4] = 1;
1786 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid;
1790 if (carpr.carpr_advbase > 0) {
1791 if (carpr.carpr_advbase > 255 ||
1792 carpr.carpr_advbase < CARP_DFLTINTV) {
1796 sc->sc_advbase = carpr.carpr_advbase;
1798 if (carpr.carpr_advskew >= 255) {
1802 sc->sc_advskew = carpr.carpr_advskew;
1803 if (carpr.carpr_key[0] != '\0') {
1804 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key));
1805 carp_hmac_prepare(sc);
1807 if (sc->sc_state != INIT &&
1808 carpr.carpr_state != sc->sc_state) {
1809 switch (carpr.carpr_state) {
1811 callout_stop(&sc->sc_ad_tmo);
1812 carp_set_state(sc, BACKUP,
1813 "user requested via ifconfig");
1818 NET_EPOCH_ENTER(et);
1819 carp_master_down_locked(sc,
1820 "user requested via ifconfig");
1833 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) {
1837 if (carpr.carpr_count < 1) {
1841 if (ifp->if_carp == NULL) {
1846 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0);
1847 if (carpr.carpr_vhid != 0) {
1848 IFNET_FOREACH_CARP(ifp, sc)
1849 if (sc->sc_vhid == carpr.carpr_vhid)
1855 carp_carprcp(&carpr, sc, priveleged);
1856 error = copyout(&carpr, ifr_data_get_ptr(ifr),
1862 IFNET_FOREACH_CARP(ifp, sc)
1865 if (count > carpr.carpr_count) {
1866 CIF_UNLOCK(ifp->if_carp);
1872 IFNET_FOREACH_CARP(ifp, sc) {
1873 carp_carprcp(&carpr, sc, priveleged);
1874 carpr.carpr_count = count;
1875 error = copyout(&carpr,
1876 (char *)ifr_data_get_ptr(ifr) +
1877 (i * sizeof(carpr)), sizeof(carpr));
1879 CIF_UNLOCK(ifp->if_carp);
1890 sx_xunlock(&carp_sx);
1901 carp_get_vhid(struct ifaddr *ifa)
1904 if (ifa == NULL || ifa->ifa_carp == NULL)
1907 return (ifa->ifa_carp->sc_vhid);
1911 carp_attach(struct ifaddr *ifa, int vhid)
1913 struct ifnet *ifp = ifa->ifa_ifp;
1914 struct carp_if *cif = ifp->if_carp;
1915 struct carp_softc *sc;
1918 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa));
1920 switch (ifa->ifa_addr->sa_family) {
1929 return (EPROTOTYPE);
1933 if (ifp->if_carp == NULL) {
1934 sx_xunlock(&carp_sx);
1935 return (ENOPROTOOPT);
1938 IFNET_FOREACH_CARP(ifp, sc)
1939 if (sc->sc_vhid == vhid)
1942 sx_xunlock(&carp_sx);
1946 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family);
1949 sx_xunlock(&carp_sx);
1953 index = sc->sc_naddrs + sc->sc_naddrs6 + 1;
1954 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *))
1957 switch (ifa->ifa_addr->sa_family) {
1975 sc->sc_ifas[index - 1] = ifa;
1977 carp_hmac_prepare(sc);
1981 sx_xunlock(&carp_sx);
1987 carp_detach(struct ifaddr *ifa, bool keep_cif)
1989 struct ifnet *ifp = ifa->ifa_ifp;
1990 struct carp_if *cif = ifp->if_carp;
1991 struct carp_softc *sc = ifa->ifa_carp;
1994 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa));
2000 index = sc->sc_naddrs + sc->sc_naddrs6;
2001 for (i = 0; i < index; i++)
2002 if (sc->sc_ifas[i] == ifa)
2004 KASSERT(i < index, ("%s: %p no backref", __func__, ifa));
2005 for (; i < index - 1; i++)
2006 sc->sc_ifas[i] = sc->sc_ifas[i+1];
2007 sc->sc_ifas[index - 1] = NULL;
2009 switch (ifa->ifa_addr->sa_family) {
2024 carp_ifa_delroute(ifa);
2025 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family);
2027 ifa->ifa_carp = NULL;
2030 carp_hmac_prepare(sc);
2033 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0)
2041 sx_xunlock(&carp_sx);
2045 carp_set_state(struct carp_softc *sc, int state, const char *reason)
2048 CARP_LOCK_ASSERT(sc);
2050 if (sc->sc_state != state) {
2051 const char *carp_states[] = { CARP_STATES };
2052 char subsys[IFNAMSIZ+5];
2054 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid,
2055 sc->sc_carpdev->if_xname);
2057 CARP_LOG("%s: %s -> %s (%s)\n", subsys,
2058 carp_states[sc->sc_state], carp_states[state], reason);
2060 sc->sc_state = state;
2062 devctl_notify("CARP", subsys, carp_states[state], NULL);
2067 carp_linkstate(struct ifnet *ifp)
2069 struct carp_softc *sc;
2071 CIF_LOCK(ifp->if_carp);
2072 IFNET_FOREACH_CARP(ifp, sc) {
2077 CIF_UNLOCK(ifp->if_carp);
2081 carp_sc_state(struct carp_softc *sc)
2084 CARP_LOCK_ASSERT(sc);
2086 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
2087 !(sc->sc_carpdev->if_flags & IFF_UP) ||
2089 callout_stop(&sc->sc_ad_tmo);
2091 callout_stop(&sc->sc_md_tmo);
2094 callout_stop(&sc->sc_md6_tmo);
2096 carp_set_state(sc, INIT, "hardware interface down");
2099 if (!sc->sc_suppress)
2100 carp_demote_adj(V_carp_ifdown_adj, "interface down");
2101 sc->sc_suppress = 1;
2103 carp_set_state(sc, INIT, "hardware interface up");
2105 if (sc->sc_suppress)
2106 carp_demote_adj(-V_carp_ifdown_adj, "interface up");
2107 sc->sc_suppress = 0;
2112 carp_demote_adj(int adj, char *reason)
2114 atomic_add_int(&V_carp_demotion, adj);
2115 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason);
2116 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task);
2120 carp_allow_sysctl(SYSCTL_HANDLER_ARGS)
2123 struct carp_softc *sc;
2126 error = sysctl_handle_int(oidp, &new, 0, req);
2127 if (error || !req->newptr)
2130 if (V_carp_allow != new) {
2133 mtx_lock(&carp_mtx);
2134 LIST_FOREACH(sc, &carp_list, sc_next) {
2136 if (curvnet == sc->sc_carpdev->if_vnet)
2140 mtx_unlock(&carp_mtx);
2147 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS)
2152 error = sysctl_handle_int(oidp, &new, 0, req);
2153 if (error || !req->newptr)
2156 if (new < 0 || new > 63)
2165 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS)
2169 new = V_carp_demotion;
2170 error = sysctl_handle_int(oidp, &new, 0, req);
2171 if (error || !req->newptr)
2174 carp_demote_adj(new, "sysctl");
2180 extern struct domain inetdomain;
2181 static struct protosw in_carp_protosw = {
2182 .pr_type = SOCK_RAW,
2183 .pr_domain = &inetdomain,
2184 .pr_protocol = IPPROTO_CARP,
2185 .pr_flags = PR_ATOMIC|PR_ADDR,
2186 .pr_input = carp_input,
2187 .pr_output = rip_output,
2188 .pr_ctloutput = rip_ctloutput,
2189 .pr_usrreqs = &rip_usrreqs
2194 extern struct domain inet6domain;
2195 static struct protosw in6_carp_protosw = {
2196 .pr_type = SOCK_RAW,
2197 .pr_domain = &inet6domain,
2198 .pr_protocol = IPPROTO_CARP,
2199 .pr_flags = PR_ATOMIC|PR_ADDR,
2200 .pr_input = carp6_input,
2201 .pr_output = rip6_output,
2202 .pr_ctloutput = rip6_ctloutput,
2203 .pr_usrreqs = &rip6_usrreqs
2208 carp_mod_cleanup(void)
2212 if (proto_reg[CARP_INET] == 0) {
2213 (void)ipproto_unregister(IPPROTO_CARP);
2214 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW);
2215 proto_reg[CARP_INET] = -1;
2217 carp_iamatch_p = NULL;
2220 if (proto_reg[CARP_INET6] == 0) {
2221 (void)ip6proto_unregister(IPPROTO_CARP);
2222 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW);
2223 proto_reg[CARP_INET6] = -1;
2225 carp_iamatch6_p = NULL;
2226 carp_macmatch6_p = NULL;
2228 carp_ioctl_p = NULL;
2229 carp_attach_p = NULL;
2230 carp_detach_p = NULL;
2231 carp_get_vhid_p = NULL;
2232 carp_linkstate_p = NULL;
2233 carp_forus_p = NULL;
2234 carp_output_p = NULL;
2235 carp_demote_adj_p = NULL;
2236 carp_master_p = NULL;
2237 mtx_unlock(&carp_mtx);
2238 taskqueue_drain(taskqueue_swi, &carp_sendall_task);
2239 mtx_destroy(&carp_mtx);
2240 sx_destroy(&carp_sx);
2244 ipcarp_sysinit(void)
2247 /* Load allow as tunable so to postpone carp start after module load */
2248 TUNABLE_INT_FETCH("net.inet.carp.allow", &V_carp_allow);
2250 VNET_SYSINIT(ip_carp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, ipcarp_sysinit, NULL);
2257 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF);
2258 sx_init(&carp_sx, "carp_sx");
2259 LIST_INIT(&carp_list);
2260 carp_get_vhid_p = carp_get_vhid;
2261 carp_forus_p = carp_forus;
2262 carp_output_p = carp_output;
2263 carp_linkstate_p = carp_linkstate;
2264 carp_ioctl_p = carp_ioctl;
2265 carp_attach_p = carp_attach;
2266 carp_detach_p = carp_detach;
2267 carp_demote_adj_p = carp_demote_adj;
2268 carp_master_p = carp_master;
2270 carp_iamatch6_p = carp_iamatch6;
2271 carp_macmatch6_p = carp_macmatch6;
2272 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6,
2273 (struct protosw *)&in6_carp_protosw);
2274 if (proto_reg[CARP_INET6]) {
2275 printf("carp: error %d attaching to PF_INET6\n",
2276 proto_reg[CARP_INET6]);
2278 return (proto_reg[CARP_INET6]);
2280 err = ip6proto_register(IPPROTO_CARP);
2282 printf("carp: error %d registering with INET6\n", err);
2288 carp_iamatch_p = carp_iamatch;
2289 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw);
2290 if (proto_reg[CARP_INET]) {
2291 printf("carp: error %d attaching to PF_INET\n",
2292 proto_reg[CARP_INET]);
2294 return (proto_reg[CARP_INET]);
2296 err = ipproto_register(IPPROTO_CARP);
2298 printf("carp: error %d registering with INET\n", err);
2307 carp_modevent(module_t mod, int type, void *data)
2311 return carp_mod_load();
2314 mtx_lock(&carp_mtx);
2315 if (LIST_EMPTY(&carp_list))
2318 mtx_unlock(&carp_mtx);
2330 static moduledata_t carp_mod = {
2336 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);