/* * Copyright (c) 2002 Michael Shalayeff. All rights reserved. * Copyright (c) 2003 Ryan McBride. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT, * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF * THE POSSIBILITY OF SUCH DAMAGE. */ #include __FBSDID("$FreeBSD: src/sys/netinet/ip_carp.c,v 1.73.2.2.2.1 2009/10/25 01:10:29 kensmith Exp $"); #include "opt_carp.h" #include "opt_bpf.h" #include "opt_inet.h" #include "opt_inet6.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #include #include #include #include #include #include #endif #ifdef INET6 #include #include #include #include #include #endif #include #include #define CARP_IFNAME "carp" static MALLOC_DEFINE(M_CARP, "CARP", "CARP interfaces"); SYSCTL_DECL(_net_inet_carp); struct carp_softc { struct ifnet *sc_ifp; /* Interface clue */ struct ifnet *sc_carpdev; /* Pointer to parent interface */ struct in_ifaddr *sc_ia; /* primary iface address */ struct ip_moptions sc_imo; #ifdef INET6 struct in6_ifaddr *sc_ia6; /* primary iface address v6 */ struct ip6_moptions sc_im6o; #endif /* INET6 */ TAILQ_ENTRY(carp_softc) sc_list; enum { INIT = 0, BACKUP, MASTER } sc_state; int sc_flags_backup; int sc_suppress; int sc_sendad_errors; #define CARP_SENDAD_MAX_ERRORS 3 int sc_sendad_success; #define CARP_SENDAD_MIN_SUCCESS 3 int sc_vhid; int sc_advskew; int sc_naddrs; int sc_naddrs6; int sc_advbase; /* seconds */ int sc_init_counter; u_int64_t sc_counter; /* authentication */ #define CARP_HMAC_PAD 64 unsigned char sc_key[CARP_KEY_LEN]; unsigned char sc_pad[CARP_HMAC_PAD]; SHA1_CTX sc_sha1; struct callout sc_ad_tmo; /* advertisement timeout */ struct callout sc_md_tmo; /* master down timeout */ struct callout sc_md6_tmo; /* master down timeout */ LIST_ENTRY(carp_softc) sc_next; /* Interface clue */ }; #define SC2IFP(sc) ((sc)->sc_ifp) int carp_suppress_preempt = 0; int carp_opts[CARPCTL_MAXID] = { 0, 1, 0, 1, 0, 0 }; /* XXX for now */ SYSCTL_INT(_net_inet_carp, CARPCTL_ALLOW, allow, CTLFLAG_RW, &carp_opts[CARPCTL_ALLOW], 0, "Accept incoming CARP packets"); SYSCTL_INT(_net_inet_carp, CARPCTL_PREEMPT, preempt, CTLFLAG_RW, &carp_opts[CARPCTL_PREEMPT], 0, "high-priority backup preemption mode"); SYSCTL_INT(_net_inet_carp, CARPCTL_LOG, log, CTLFLAG_RW, &carp_opts[CARPCTL_LOG], 0, "log bad carp packets"); SYSCTL_INT(_net_inet_carp, CARPCTL_ARPBALANCE, arpbalance, CTLFLAG_RW, &carp_opts[CARPCTL_ARPBALANCE], 0, "balance arp responses"); SYSCTL_INT(_net_inet_carp, OID_AUTO, suppress_preempt, CTLFLAG_RD, &carp_suppress_preempt, 0, "Preemption is suppressed"); struct carpstats carpstats; SYSCTL_STRUCT(_net_inet_carp, CARPCTL_STATS, stats, CTLFLAG_RW, &carpstats, carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); struct carp_if { TAILQ_HEAD(, carp_softc) vhif_vrs; int vhif_nvrs; struct ifnet *vhif_ifp; struct mtx vhif_mtx; }; /* Get carp_if from softc. Valid after carp_set_addr{,6}. */ #define SC2CIF(sc) ((struct carp_if *)(sc)->sc_carpdev->if_carp) /* lock per carp_if queue */ #define CARP_LOCK_INIT(cif) mtx_init(&(cif)->vhif_mtx, "carp_if", \ NULL, MTX_DEF) #define CARP_LOCK_DESTROY(cif) mtx_destroy(&(cif)->vhif_mtx) #define CARP_LOCK_ASSERT(cif) mtx_assert(&(cif)->vhif_mtx, MA_OWNED) #define CARP_LOCK(cif) mtx_lock(&(cif)->vhif_mtx) #define CARP_UNLOCK(cif) mtx_unlock(&(cif)->vhif_mtx) #define CARP_SCLOCK(sc) mtx_lock(&SC2CIF(sc)->vhif_mtx) #define CARP_SCUNLOCK(sc) mtx_unlock(&SC2CIF(sc)->vhif_mtx) #define CARP_SCLOCK_ASSERT(sc) mtx_assert(&SC2CIF(sc)->vhif_mtx, MA_OWNED) #define CARP_LOG(...) do { \ if (carp_opts[CARPCTL_LOG] > 0) \ log(LOG_INFO, __VA_ARGS__); \ } while (0) #define CARP_DEBUG(...) do { \ if (carp_opts[CARPCTL_LOG] > 1) \ log(LOG_DEBUG, __VA_ARGS__); \ } while (0) static void carp_hmac_prepare(struct carp_softc *); static void carp_hmac_generate(struct carp_softc *, u_int32_t *, unsigned char *); static int carp_hmac_verify(struct carp_softc *, u_int32_t *, unsigned char *); static void carp_setroute(struct carp_softc *, int); static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); static int carp_clone_create(struct if_clone *, int, caddr_t); static void carp_clone_destroy(struct ifnet *); static void carpdetach(struct carp_softc *, int); static int carp_prepare_ad(struct mbuf *, struct carp_softc *, struct carp_header *); static void carp_send_ad_all(void); static void carp_send_ad(void *); static void carp_send_ad_locked(struct carp_softc *); static void carp_send_arp(struct carp_softc *); static void carp_master_down(void *); static void carp_master_down_locked(struct carp_softc *); static int carp_ioctl(struct ifnet *, u_long, caddr_t); static int carp_looutput(struct ifnet *, struct mbuf *, struct sockaddr *, struct route *); static void carp_start(struct ifnet *); static void carp_setrun(struct carp_softc *, sa_family_t); static void carp_set_state(struct carp_softc *, int); static int carp_addrcount(struct carp_if *, struct in_ifaddr *, int); enum { CARP_COUNT_MASTER, CARP_COUNT_RUNNING }; static void carp_multicast_cleanup(struct carp_softc *); static int carp_set_addr(struct carp_softc *, struct sockaddr_in *); static int carp_del_addr(struct carp_softc *, struct sockaddr_in *); static void carp_carpdev_state_locked(struct carp_if *); static void carp_sc_state_locked(struct carp_softc *); #ifdef INET6 static void carp_send_na(struct carp_softc *); static int carp_set_addr6(struct carp_softc *, struct sockaddr_in6 *); static int carp_del_addr6(struct carp_softc *, struct sockaddr_in6 *); static void carp_multicast6_cleanup(struct carp_softc *); #endif static LIST_HEAD(, carp_softc) carpif_list; static struct mtx carp_mtx; IFC_SIMPLE_DECLARE(carp, 0); static eventhandler_tag if_detach_event_tag; static __inline u_int16_t carp_cksum(struct mbuf *m, int len) { return (in_cksum(m, len)); } static void carp_hmac_prepare(struct carp_softc *sc) { u_int8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; u_int8_t vhid = sc->sc_vhid & 0xff; struct ifaddr *ifa; int i, found; #ifdef INET struct in_addr last, cur, in; #endif #ifdef INET6 struct in6_addr last6, cur6, in6; #endif if (sc->sc_carpdev) CARP_SCLOCK(sc); /* XXX: possible race here */ /* compute ipad from key */ bzero(sc->sc_pad, sizeof(sc->sc_pad)); bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); for (i = 0; i < sizeof(sc->sc_pad); i++) sc->sc_pad[i] ^= 0x36; /* precompute first part of inner hash */ SHA1Init(&sc->sc_sha1); SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); #ifdef INET cur.s_addr = 0; do { found = 0; last = cur; cur.s_addr = 0xffffffff; IF_ADDR_LOCK(SC2IFP(sc)); TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; if (ifa->ifa_addr->sa_family == AF_INET && ntohl(in.s_addr) > ntohl(last.s_addr) && ntohl(in.s_addr) < ntohl(cur.s_addr)) { cur.s_addr = in.s_addr; found++; } } IF_ADDR_UNLOCK(SC2IFP(sc)); if (found) SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); } while (found); #endif /* INET */ #ifdef INET6 memset(&cur6, 0, sizeof(cur6)); do { found = 0; last6 = cur6; memset(&cur6, 0xff, sizeof(cur6)); IF_ADDR_LOCK(SC2IFP(sc)); TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { in6 = ifatoia6(ifa)->ia_addr.sin6_addr; if (IN6_IS_SCOPE_EMBED(&in6)) in6.s6_addr16[1] = 0; if (ifa->ifa_addr->sa_family == AF_INET6 && memcmp(&in6, &last6, sizeof(in6)) > 0 && memcmp(&in6, &cur6, sizeof(in6)) < 0) { cur6 = in6; found++; } } IF_ADDR_UNLOCK(SC2IFP(sc)); if (found) SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); } while (found); #endif /* INET6 */ /* convert ipad to opad */ for (i = 0; i < sizeof(sc->sc_pad); i++) sc->sc_pad[i] ^= 0x36 ^ 0x5c; if (sc->sc_carpdev) CARP_SCUNLOCK(sc); } static void carp_hmac_generate(struct carp_softc *sc, u_int32_t counter[2], unsigned char md[20]) { SHA1_CTX sha1ctx; /* fetch first half of inner hash */ bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); SHA1Final(md, &sha1ctx); /* outer hash */ SHA1Init(&sha1ctx); SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); SHA1Update(&sha1ctx, md, 20); SHA1Final(md, &sha1ctx); } static int carp_hmac_verify(struct carp_softc *sc, u_int32_t counter[2], unsigned char md[20]) { unsigned char md2[20]; CARP_SCLOCK_ASSERT(sc); carp_hmac_generate(sc, counter, md2); return (bcmp(md, md2, sizeof(md2))); } static void carp_setroute(struct carp_softc *sc, int cmd) { struct ifaddr *ifa; int s; if (sc->sc_carpdev) CARP_SCLOCK_ASSERT(sc); s = splnet(); TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family == AF_INET && sc->sc_carpdev != NULL) { int count = carp_addrcount( (struct carp_if *)sc->sc_carpdev->if_carp, ifatoia(ifa), CARP_COUNT_MASTER); if ((cmd == RTM_ADD && count == 1) || (cmd == RTM_DELETE && count == 0)) rtinit(ifa, cmd, RTF_UP | RTF_HOST); } } splx(s); } static int carp_clone_create(struct if_clone *ifc, int unit, caddr_t params) { struct carp_softc *sc; struct ifnet *ifp; sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); ifp = SC2IFP(sc) = if_alloc(IFT_ETHER); if (ifp == NULL) { free(sc, M_CARP); return (ENOSPC); } sc->sc_flags_backup = 0; sc->sc_suppress = 0; sc->sc_advbase = CARP_DFLTINTV; sc->sc_vhid = -1; /* required setting */ sc->sc_advskew = 0; sc->sc_init_counter = 1; sc->sc_naddrs = sc->sc_naddrs6 = 0; /* M_ZERO? */ sc->sc_imo.imo_membership = (struct in_multi **)malloc( (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, M_WAITOK); sc->sc_imo.imo_mfilters = NULL; sc->sc_imo.imo_max_memberships = IP_MIN_MEMBERSHIPS; sc->sc_imo.imo_multicast_vif = -1; #ifdef INET6 sc->sc_im6o.im6o_membership = (struct in6_multi **)malloc( (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, M_WAITOK); sc->sc_im6o.im6o_mfilters = NULL; sc->sc_im6o.im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; sc->sc_im6o.im6o_multicast_hlim = CARP_DFLTTL; #endif callout_init(&sc->sc_ad_tmo, CALLOUT_MPSAFE); callout_init(&sc->sc_md_tmo, CALLOUT_MPSAFE); callout_init(&sc->sc_md6_tmo, CALLOUT_MPSAFE); ifp->if_softc = sc; if_initname(ifp, CARP_IFNAME, unit); ifp->if_mtu = ETHERMTU; ifp->if_flags = IFF_LOOPBACK; ifp->if_ioctl = carp_ioctl; ifp->if_output = carp_looutput; ifp->if_start = carp_start; ifp->if_type = IFT_CARP; ifp->if_snd.ifq_maxlen = ifqmaxlen; ifp->if_hdrlen = 0; if_attach(ifp); bpfattach(SC2IFP(sc), DLT_NULL, sizeof(u_int32_t)); mtx_lock(&carp_mtx); LIST_INSERT_HEAD(&carpif_list, sc, sc_next); mtx_unlock(&carp_mtx); return (0); } static void carp_clone_destroy(struct ifnet *ifp) { struct carp_softc *sc = ifp->if_softc; if (sc->sc_carpdev) CARP_SCLOCK(sc); carpdetach(sc, 1); /* Returns unlocked. */ mtx_lock(&carp_mtx); LIST_REMOVE(sc, sc_next); mtx_unlock(&carp_mtx); bpfdetach(ifp); if_detach(ifp); if_free_type(ifp, IFT_ETHER); free(sc->sc_imo.imo_membership, M_CARP); #ifdef INET6 free(sc->sc_im6o.im6o_membership, M_CARP); #endif free(sc, M_CARP); } /* * This function can be called on CARP interface destroy path, * and in case of the removal of the underlying interface as * well. We differentiate these two cases. In the latter case * we do not cleanup our multicast memberships, since they * are already freed. Also, in the latter case we do not * release the lock on return, because the function will be * called once more, for another CARP instance on the same * interface. */ static void carpdetach(struct carp_softc *sc, int unlock) { struct carp_if *cif; callout_stop(&sc->sc_ad_tmo); callout_stop(&sc->sc_md_tmo); callout_stop(&sc->sc_md6_tmo); if (sc->sc_suppress) carp_suppress_preempt--; sc->sc_suppress = 0; if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) carp_suppress_preempt--; sc->sc_sendad_errors = 0; carp_set_state(sc, INIT); SC2IFP(sc)->if_flags &= ~IFF_UP; carp_setrun(sc, 0); if (unlock) carp_multicast_cleanup(sc); #ifdef INET6 carp_multicast6_cleanup(sc); #endif if (sc->sc_carpdev != NULL) { cif = (struct carp_if *)sc->sc_carpdev->if_carp; CARP_LOCK_ASSERT(cif); TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list); if (!--cif->vhif_nvrs) { ifpromisc(sc->sc_carpdev, 0); sc->sc_carpdev->if_carp = NULL; CARP_LOCK_DESTROY(cif); free(cif, M_CARP); } else if (unlock) CARP_UNLOCK(cif); sc->sc_carpdev = NULL; } } /* Detach an interface from the carp. */ static void carp_ifdetach(void *arg __unused, struct ifnet *ifp) { struct carp_if *cif = (struct carp_if *)ifp->if_carp; struct carp_softc *sc, *nextsc; if (cif == NULL) return; /* * XXX: At the end of for() cycle the lock will be destroyed. */ CARP_LOCK(cif); for (sc = TAILQ_FIRST(&cif->vhif_vrs); sc; sc = nextsc) { nextsc = TAILQ_NEXT(sc, sc_list); carpdetach(sc, 0); } } /* * process input packet. * we have rearranged checks order compared to the rfc, * but it seems more efficient this way or not possible otherwise. */ void carp_input(struct mbuf *m, int hlen) { struct ip *ip = mtod(m, struct ip *); struct carp_header *ch; int iplen, len; CARPSTATS_INC(carps_ipackets); if (!carp_opts[CARPCTL_ALLOW]) { m_freem(m); return; } /* check if received on a valid carp interface */ if (m->m_pkthdr.rcvif->if_carp == NULL) { CARPSTATS_INC(carps_badif); CARP_LOG("carp_input: packet received on non-carp " "interface: %s\n", m->m_pkthdr.rcvif->if_xname); m_freem(m); return; } /* verify that the IP TTL is 255. */ if (ip->ip_ttl != CARP_DFLTTL) { CARPSTATS_INC(carps_badttl); CARP_LOG("carp_input: received ttl %d != 255i on %s\n", ip->ip_ttl, m->m_pkthdr.rcvif->if_xname); m_freem(m); return; } iplen = ip->ip_hl << 2; if (m->m_pkthdr.len < iplen + sizeof(*ch)) { CARPSTATS_INC(carps_badlen); CARP_LOG("carp_input: received len %zd < " "sizeof(struct carp_header) on %s\n", m->m_len - sizeof(struct ip), m->m_pkthdr.rcvif->if_xname); m_freem(m); return; } if (iplen + sizeof(*ch) < m->m_len) { if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { CARPSTATS_INC(carps_hdrops); CARP_LOG("carp_input: pullup failed\n"); return; } ip = mtod(m, struct ip *); } ch = (struct carp_header *)((char *)ip + iplen); /* * verify that the received packet length is * equal to the CARP header */ len = iplen + sizeof(*ch); if (len > m->m_pkthdr.len) { CARPSTATS_INC(carps_badlen); CARP_LOG("carp_input: packet too short %d on %s\n", m->m_pkthdr.len, m->m_pkthdr.rcvif->if_xname); m_freem(m); return; } if ((m = m_pullup(m, len)) == NULL) { CARPSTATS_INC(carps_hdrops); return; } ip = mtod(m, struct ip *); ch = (struct carp_header *)((char *)ip + iplen); /* verify the CARP checksum */ m->m_data += iplen; if (carp_cksum(m, len - iplen)) { CARPSTATS_INC(carps_badsum); CARP_LOG("carp_input: checksum failed on %s\n", m->m_pkthdr.rcvif->if_xname); m_freem(m); return; } m->m_data -= iplen; carp_input_c(m, ch, AF_INET); } #ifdef INET6 int carp6_input(struct mbuf **mp, int *offp, int proto) { struct mbuf *m = *mp; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct carp_header *ch; u_int len; CARPSTATS_INC(carps_ipackets6); if (!carp_opts[CARPCTL_ALLOW]) { m_freem(m); return (IPPROTO_DONE); } /* check if received on a valid carp interface */ if (m->m_pkthdr.rcvif->if_carp == NULL) { CARPSTATS_INC(carps_badif); CARP_LOG("carp6_input: packet received on non-carp " "interface: %s\n", m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } /* verify that the IP TTL is 255 */ if (ip6->ip6_hlim != CARP_DFLTTL) { CARPSTATS_INC(carps_badttl); CARP_LOG("carp6_input: received ttl %d != 255 on %s\n", ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } /* verify that we have a complete carp packet */ len = m->m_len; IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch)); if (ch == NULL) { CARPSTATS_INC(carps_badlen); CARP_LOG("carp6_input: packet size %u too small\n", len); return (IPPROTO_DONE); } /* verify the CARP checksum */ m->m_data += *offp; if (carp_cksum(m, sizeof(*ch))) { CARPSTATS_INC(carps_badsum); CARP_LOG("carp6_input: checksum failed, on %s\n", m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } m->m_data -= *offp; carp_input_c(m, ch, AF_INET6); return (IPPROTO_DONE); } #endif /* INET6 */ static void carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) { struct ifnet *ifp = m->m_pkthdr.rcvif; struct carp_softc *sc; u_int64_t tmp_counter; struct timeval sc_tv, ch_tv; /* verify that the VHID is valid on the receiving interface */ CARP_LOCK(ifp->if_carp); TAILQ_FOREACH(sc, &((struct carp_if *)ifp->if_carp)->vhif_vrs, sc_list) if (sc->sc_vhid == ch->carp_vhid) break; if (!sc || !((SC2IFP(sc)->if_flags & IFF_UP) && (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) { CARPSTATS_INC(carps_badvhid); CARP_UNLOCK(ifp->if_carp); m_freem(m); return; } getmicrotime(&SC2IFP(sc)->if_lastchange); SC2IFP(sc)->if_ipackets++; SC2IFP(sc)->if_ibytes += m->m_pkthdr.len; if (bpf_peers_present(SC2IFP(sc)->if_bpf)) { struct ip *ip = mtod(m, struct ip *); uint32_t af1 = af; /* BPF wants net byte order */ ip->ip_len = htons(ip->ip_len + (ip->ip_hl << 2)); ip->ip_off = htons(ip->ip_off); bpf_mtap2(SC2IFP(sc)->if_bpf, &af1, sizeof(af1), m); } /* verify the CARP version. */ if (ch->carp_version != CARP_VERSION) { CARPSTATS_INC(carps_badver); SC2IFP(sc)->if_ierrors++; CARP_UNLOCK(ifp->if_carp); CARP_LOG("%s; invalid version %d\n", SC2IFP(sc)->if_xname, ch->carp_version); m_freem(m); return; } /* verify the hash */ if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { CARPSTATS_INC(carps_badauth); SC2IFP(sc)->if_ierrors++; CARP_UNLOCK(ifp->if_carp); CARP_LOG("%s: incorrect hash\n", SC2IFP(sc)->if_xname); m_freem(m); return; } tmp_counter = ntohl(ch->carp_counter[0]); tmp_counter = tmp_counter<<32; tmp_counter += ntohl(ch->carp_counter[1]); /* XXX Replay protection goes here */ sc->sc_init_counter = 0; sc->sc_counter = tmp_counter; sc_tv.tv_sec = sc->sc_advbase; if (carp_suppress_preempt && sc->sc_advskew < 240) sc_tv.tv_usec = 240 * 1000000 / 256; else sc_tv.tv_usec = sc->sc_advskew * 1000000 / 256; ch_tv.tv_sec = ch->carp_advbase; ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; switch (sc->sc_state) { case INIT: break; case MASTER: /* * If we receive an advertisement from a master who's going to * be more frequent than us, go into BACKUP state. */ if (timevalcmp(&sc_tv, &ch_tv, >) || timevalcmp(&sc_tv, &ch_tv, ==)) { callout_stop(&sc->sc_ad_tmo); CARP_DEBUG("%s: MASTER -> BACKUP " "(more frequent advertisement received)\n", SC2IFP(sc)->if_xname); carp_set_state(sc, BACKUP); carp_setrun(sc, 0); carp_setroute(sc, RTM_DELETE); } break; case BACKUP: /* * If we're pre-empting masters who advertise slower than us, * and this one claims to be slower, treat him as down. */ if (carp_opts[CARPCTL_PREEMPT] && timevalcmp(&sc_tv, &ch_tv, <)) { CARP_DEBUG("%s: BACKUP -> MASTER " "(preempting a slower master)\n", SC2IFP(sc)->if_xname); carp_master_down_locked(sc); break; } /* * If the master is going to advertise at such a low frequency * that he's guaranteed to time out, we'd might as well just * treat him as timed out now. */ sc_tv.tv_sec = sc->sc_advbase * 3; if (timevalcmp(&sc_tv, &ch_tv, <)) { CARP_DEBUG("%s: BACKUP -> MASTER " "(master timed out)\n", SC2IFP(sc)->if_xname); carp_master_down_locked(sc); break; } /* * Otherwise, we reset the counter and wait for the next * advertisement. */ carp_setrun(sc, af); break; } CARP_UNLOCK(ifp->if_carp); m_freem(m); return; } static int carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) { struct m_tag *mtag; struct ifnet *ifp = SC2IFP(sc); if (sc->sc_init_counter) { /* this could also be seconds since unix epoch */ sc->sc_counter = arc4random(); sc->sc_counter = sc->sc_counter << 32; sc->sc_counter += arc4random(); } else sc->sc_counter++; ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); /* Tag packet for carp_output */ mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct ifnet *), M_NOWAIT); if (mtag == NULL) { m_freem(m); SC2IFP(sc)->if_oerrors++; return (ENOMEM); } bcopy(&ifp, (caddr_t)(mtag + 1), sizeof(struct ifnet *)); m_tag_prepend(m, mtag); return (0); } static void carp_send_ad_all(void) { struct carp_softc *sc; mtx_lock(&carp_mtx); LIST_FOREACH(sc, &carpif_list, sc_next) { if (sc->sc_carpdev == NULL) continue; CARP_SCLOCK(sc); if ((SC2IFP(sc)->if_flags & IFF_UP) && (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING) && sc->sc_state == MASTER) carp_send_ad_locked(sc); CARP_SCUNLOCK(sc); } mtx_unlock(&carp_mtx); } static void carp_send_ad(void *v) { struct carp_softc *sc = v; CARP_SCLOCK(sc); carp_send_ad_locked(sc); CARP_SCUNLOCK(sc); } static void carp_send_ad_locked(struct carp_softc *sc) { struct carp_header ch; struct timeval tv; struct carp_header *ch_ptr; struct mbuf *m; int len, advbase, advskew; CARP_SCLOCK_ASSERT(sc); /* bow out if we've lost our UPness or RUNNINGuiness */ if (!((SC2IFP(sc)->if_flags & IFF_UP) && (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING))) { advbase = 255; advskew = 255; } else { advbase = sc->sc_advbase; if (!carp_suppress_preempt || sc->sc_advskew > 240) advskew = sc->sc_advskew; else advskew = 240; tv.tv_sec = advbase; tv.tv_usec = advskew * 1000000 / 256; } ch.carp_version = CARP_VERSION; ch.carp_type = CARP_ADVERTISEMENT; ch.carp_vhid = sc->sc_vhid; ch.carp_advbase = advbase; ch.carp_advskew = advskew; ch.carp_authlen = 7; /* XXX DEFINE */ ch.carp_pad1 = 0; /* must be zero */ ch.carp_cksum = 0; #ifdef INET if (sc->sc_ia) { struct ip *ip; MGETHDR(m, M_DONTWAIT, MT_HEADER); if (m == NULL) { SC2IFP(sc)->if_oerrors++; CARPSTATS_INC(carps_onomem); /* XXX maybe less ? */ if (advbase != 255 || advskew != 255) callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); return; } len = sizeof(*ip) + sizeof(ch); m->m_pkthdr.len = len; m->m_pkthdr.rcvif = NULL; m->m_len = len; MH_ALIGN(m, m->m_len); m->m_flags |= M_MCAST; ip = mtod(m, struct ip *); ip->ip_v = IPVERSION; ip->ip_hl = sizeof(*ip) >> 2; ip->ip_tos = IPTOS_LOWDELAY; ip->ip_len = len; ip->ip_id = ip_newid(); ip->ip_off = IP_DF; ip->ip_ttl = CARP_DFLTTL; ip->ip_p = IPPROTO_CARP; ip->ip_sum = 0; ip->ip_src.s_addr = sc->sc_ia->ia_addr.sin_addr.s_addr; ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); ch_ptr = (struct carp_header *)(&ip[1]); bcopy(&ch, ch_ptr, sizeof(ch)); if (carp_prepare_ad(m, sc, ch_ptr)) return; m->m_data += sizeof(*ip); ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip)); m->m_data -= sizeof(*ip); getmicrotime(&SC2IFP(sc)->if_lastchange); SC2IFP(sc)->if_opackets++; SC2IFP(sc)->if_obytes += len; CARPSTATS_INC(carps_opackets); if (ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_imo, NULL)) { SC2IFP(sc)->if_oerrors++; if (sc->sc_sendad_errors < INT_MAX) sc->sc_sendad_errors++; if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { carp_suppress_preempt++; if (carp_suppress_preempt == 1) { CARP_SCUNLOCK(sc); carp_send_ad_all(); CARP_SCLOCK(sc); } } sc->sc_sendad_success = 0; } else { if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) { if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { carp_suppress_preempt--; sc->sc_sendad_errors = 0; } } else sc->sc_sendad_errors = 0; } } #endif /* INET */ #ifdef INET6 if (sc->sc_ia6) { struct ip6_hdr *ip6; MGETHDR(m, M_DONTWAIT, MT_HEADER); if (m == NULL) { SC2IFP(sc)->if_oerrors++; CARPSTATS_INC(carps_onomem); /* XXX maybe less ? */ if (advbase != 255 || advskew != 255) callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); return; } len = sizeof(*ip6) + sizeof(ch); m->m_pkthdr.len = len; m->m_pkthdr.rcvif = NULL; m->m_len = len; MH_ALIGN(m, m->m_len); m->m_flags |= M_MCAST; ip6 = mtod(m, struct ip6_hdr *); bzero(ip6, sizeof(*ip6)); ip6->ip6_vfc |= IPV6_VERSION; ip6->ip6_hlim = CARP_DFLTTL; ip6->ip6_nxt = IPPROTO_CARP; bcopy(&sc->sc_ia6->ia_addr.sin6_addr, &ip6->ip6_src, sizeof(struct in6_addr)); /* set the multicast destination */ ip6->ip6_dst.s6_addr16[0] = htons(0xff02); ip6->ip6_dst.s6_addr8[15] = 0x12; if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { SC2IFP(sc)->if_oerrors++; m_freem(m); CARP_LOG("%s: in6_setscope failed\n", __func__); return; } ch_ptr = (struct carp_header *)(&ip6[1]); bcopy(&ch, ch_ptr, sizeof(ch)); if (carp_prepare_ad(m, sc, ch_ptr)) return; m->m_data += sizeof(*ip6); ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip6)); m->m_data -= sizeof(*ip6); getmicrotime(&SC2IFP(sc)->if_lastchange); SC2IFP(sc)->if_opackets++; SC2IFP(sc)->if_obytes += len; CARPSTATS_INC(carps_opackets6); if (ip6_output(m, NULL, NULL, 0, &sc->sc_im6o, NULL, NULL)) { SC2IFP(sc)->if_oerrors++; if (sc->sc_sendad_errors < INT_MAX) sc->sc_sendad_errors++; if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { carp_suppress_preempt++; if (carp_suppress_preempt == 1) { CARP_SCUNLOCK(sc); carp_send_ad_all(); CARP_SCLOCK(sc); } } sc->sc_sendad_success = 0; } else { if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) { if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { carp_suppress_preempt--; sc->sc_sendad_errors = 0; } } else sc->sc_sendad_errors = 0; } } #endif /* INET6 */ if (advbase != 255 || advskew != 255) callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); } /* * Broadcast a gratuitous ARP request containing * the virtual router MAC address for each IP address * associated with the virtual router. */ static void carp_send_arp(struct carp_softc *sc) { struct ifaddr *ifa; TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family != AF_INET) continue; /* arprequest(sc->sc_carpdev, &in, &in, IF_LLADDR(sc->sc_ifp)); */ arp_ifinit2(sc->sc_carpdev, ifa, IF_LLADDR(sc->sc_ifp)); DELAY(1000); /* XXX */ } } #ifdef INET6 static void carp_send_na(struct carp_softc *sc) { struct ifaddr *ifa; struct in6_addr *in6; static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; in6 = &ifatoia6(ifa)->ia_addr.sin6_addr; nd6_na_output(sc->sc_carpdev, &mcast, in6, ND_NA_FLAG_OVERRIDE, 1, NULL); DELAY(1000); /* XXX */ } } #endif /* INET6 */ static int carp_addrcount(struct carp_if *cif, struct in_ifaddr *ia, int type) { struct carp_softc *vh; struct ifaddr *ifa; int count = 0; CARP_LOCK_ASSERT(cif); TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { if ((type == CARP_COUNT_RUNNING && (SC2IFP(vh)->if_flags & IFF_UP) && (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) || (type == CARP_COUNT_MASTER && vh->sc_state == MASTER)) { IF_ADDR_LOCK(SC2IFP(vh)); TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family == AF_INET && ia->ia_addr.sin_addr.s_addr == ifatoia(ifa)->ia_addr.sin_addr.s_addr) count++; } IF_ADDR_UNLOCK(SC2IFP(vh)); } } return (count); } int carp_iamatch(void *v, struct in_ifaddr *ia, struct in_addr *isaddr, u_int8_t **enaddr) { struct carp_if *cif = v; struct carp_softc *vh; int index, count = 0; struct ifaddr *ifa; CARP_LOCK(cif); if (carp_opts[CARPCTL_ARPBALANCE]) { /* * XXX proof of concept implementation. * We use the source ip to decide which virtual host should * handle the request. If we're master of that virtual host, * then we respond, otherwise, just drop the arp packet on * the floor. */ count = carp_addrcount(cif, ia, CARP_COUNT_RUNNING); if (count == 0) { /* should never reach this */ CARP_UNLOCK(cif); return (0); } /* this should be a hash, like pf_hash() */ index = ntohl(isaddr->s_addr) % count; count = 0; TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { if ((SC2IFP(vh)->if_flags & IFF_UP) && (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING)) { IF_ADDR_LOCK(SC2IFP(vh)); TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist, ifa_list) { if (ifa->ifa_addr->sa_family == AF_INET && ia->ia_addr.sin_addr.s_addr == ifatoia(ifa)->ia_addr.sin_addr.s_addr) { if (count == index) { if (vh->sc_state == MASTER) { *enaddr = IF_LLADDR(vh->sc_ifp); IF_ADDR_UNLOCK(SC2IFP(vh)); CARP_UNLOCK(cif); return (1); } else { IF_ADDR_UNLOCK(SC2IFP(vh)); CARP_UNLOCK(cif); return (0); } } count++; } } IF_ADDR_UNLOCK(SC2IFP(vh)); } } } else { TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { if ((SC2IFP(vh)->if_flags & IFF_UP) && (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) && ia->ia_ifp == SC2IFP(vh) && vh->sc_state == MASTER) { *enaddr = IF_LLADDR(vh->sc_ifp); CARP_UNLOCK(cif); return (1); } } } CARP_UNLOCK(cif); return (0); } #ifdef INET6 struct ifaddr * carp_iamatch6(void *v, struct in6_addr *taddr) { struct carp_if *cif = v; struct carp_softc *vh; struct ifaddr *ifa; CARP_LOCK(cif); TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { IF_ADDR_LOCK(SC2IFP(vh)); TAILQ_FOREACH(ifa, &SC2IFP(vh)->if_addrlist, ifa_list) { if (IN6_ARE_ADDR_EQUAL(taddr, &ifatoia6(ifa)->ia_addr.sin6_addr) && (SC2IFP(vh)->if_flags & IFF_UP) && (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) && vh->sc_state == MASTER) { ifa_ref(ifa); IF_ADDR_UNLOCK(SC2IFP(vh)); CARP_UNLOCK(cif); return (ifa); } } IF_ADDR_UNLOCK(SC2IFP(vh)); } CARP_UNLOCK(cif); return (NULL); } void * carp_macmatch6(void *v, struct mbuf *m, const struct in6_addr *taddr) { struct m_tag *mtag; struct carp_if *cif = v; struct carp_softc *sc; struct ifaddr *ifa; CARP_LOCK(cif); TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) { IF_ADDR_LOCK(SC2IFP(sc)); TAILQ_FOREACH(ifa, &SC2IFP(sc)->if_addrlist, ifa_list) { if (IN6_ARE_ADDR_EQUAL(taddr, &ifatoia6(ifa)->ia_addr.sin6_addr) && (SC2IFP(sc)->if_flags & IFF_UP) && (SC2IFP(sc)->if_drv_flags & IFF_DRV_RUNNING)) { struct ifnet *ifp = SC2IFP(sc); mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct ifnet *), M_NOWAIT); if (mtag == NULL) { /* better a bit than nothing */ IF_ADDR_UNLOCK(SC2IFP(sc)); CARP_UNLOCK(cif); return (IF_LLADDR(sc->sc_ifp)); } bcopy(&ifp, (caddr_t)(mtag + 1), sizeof(struct ifnet *)); m_tag_prepend(m, mtag); IF_ADDR_UNLOCK(SC2IFP(sc)); CARP_UNLOCK(cif); return (IF_LLADDR(sc->sc_ifp)); } } IF_ADDR_UNLOCK(SC2IFP(sc)); } CARP_UNLOCK(cif); return (NULL); } #endif struct ifnet * carp_forus(void *v, void *dhost) { struct carp_if *cif = v; struct carp_softc *vh; u_int8_t *ena = dhost; if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) return (NULL); CARP_LOCK(cif); TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) if ((SC2IFP(vh)->if_flags & IFF_UP) && (SC2IFP(vh)->if_drv_flags & IFF_DRV_RUNNING) && vh->sc_state == MASTER && !bcmp(dhost, IF_LLADDR(vh->sc_ifp), ETHER_ADDR_LEN)) { CARP_UNLOCK(cif); return (SC2IFP(vh)); } CARP_UNLOCK(cif); return (NULL); } static void carp_master_down(void *v) { struct carp_softc *sc = v; CARP_SCLOCK(sc); carp_master_down_locked(sc); CARP_SCUNLOCK(sc); } static void carp_master_down_locked(struct carp_softc *sc) { if (sc->sc_carpdev) CARP_SCLOCK_ASSERT(sc); switch (sc->sc_state) { case INIT: printf("%s: master_down event in INIT state\n", SC2IFP(sc)->if_xname); break; case MASTER: break; case BACKUP: carp_set_state(sc, MASTER); carp_send_ad_locked(sc); carp_send_arp(sc); #ifdef INET6 carp_send_na(sc); #endif /* INET6 */ carp_setrun(sc, 0); carp_setroute(sc, RTM_ADD); break; } } /* * When in backup state, af indicates whether to reset the master down timer * for v4 or v6. If it's set to zero, reset the ones which are already pending. */ static void carp_setrun(struct carp_softc *sc, sa_family_t af) { struct timeval tv; if (sc->sc_carpdev == NULL) { SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; carp_set_state(sc, INIT); return; } else CARP_SCLOCK_ASSERT(sc); if (SC2IFP(sc)->if_flags & IFF_UP && sc->sc_vhid > 0 && (sc->sc_naddrs || sc->sc_naddrs6)) SC2IFP(sc)->if_drv_flags |= IFF_DRV_RUNNING; else { SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; carp_setroute(sc, RTM_DELETE); return; } switch (sc->sc_state) { case INIT: if (carp_opts[CARPCTL_PREEMPT] && !carp_suppress_preempt) { carp_send_ad_locked(sc); carp_send_arp(sc); #ifdef INET6 carp_send_na(sc); #endif /* INET6 */ CARP_DEBUG("%s: INIT -> MASTER (preempting)\n", SC2IFP(sc)->if_xname); carp_set_state(sc, MASTER); carp_setroute(sc, RTM_ADD); } else { CARP_DEBUG("%s: INIT -> BACKUP\n", SC2IFP(sc)->if_xname); carp_set_state(sc, BACKUP); carp_setroute(sc, RTM_DELETE); carp_setrun(sc, 0); } break; case BACKUP: callout_stop(&sc->sc_ad_tmo); tv.tv_sec = 3 * sc->sc_advbase; tv.tv_usec = sc->sc_advskew * 1000000 / 256; switch (af) { #ifdef INET case AF_INET: callout_reset(&sc->sc_md_tmo, tvtohz(&tv), carp_master_down, sc); break; #endif /* INET */ #ifdef INET6 case AF_INET6: callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), carp_master_down, sc); break; #endif /* INET6 */ default: if (sc->sc_naddrs) callout_reset(&sc->sc_md_tmo, tvtohz(&tv), carp_master_down, sc); if (sc->sc_naddrs6) callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), carp_master_down, sc); break; } break; case MASTER: tv.tv_sec = sc->sc_advbase; tv.tv_usec = sc->sc_advskew * 1000000 / 256; callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); break; } } static void carp_multicast_cleanup(struct carp_softc *sc) { struct ip_moptions *imo = &sc->sc_imo; u_int16_t n = imo->imo_num_memberships; /* Clean up our own multicast memberships */ while (n-- > 0) { if (imo->imo_membership[n] != NULL) { in_delmulti(imo->imo_membership[n]); imo->imo_membership[n] = NULL; } } KASSERT(imo->imo_mfilters == NULL, ("%s: imo_mfilters != NULL", __func__)); imo->imo_num_memberships = 0; imo->imo_multicast_ifp = NULL; } #ifdef INET6 static void carp_multicast6_cleanup(struct carp_softc *sc) { struct ip6_moptions *im6o = &sc->sc_im6o; u_int16_t n = im6o->im6o_num_memberships; while (n-- > 0) { if (im6o->im6o_membership[n] != NULL) { in6_mc_leave(im6o->im6o_membership[n], NULL); im6o->im6o_membership[n] = NULL; } } KASSERT(im6o->im6o_mfilters == NULL, ("%s: im6o_mfilters != NULL", __func__)); im6o->im6o_num_memberships = 0; im6o->im6o_multicast_ifp = NULL; } #endif static int carp_set_addr(struct carp_softc *sc, struct sockaddr_in *sin) { struct ifnet *ifp; struct carp_if *cif; struct in_ifaddr *ia, *ia_if; struct ip_moptions *imo = &sc->sc_imo; struct in_addr addr; u_long iaddr = htonl(sin->sin_addr.s_addr); int own, error; if (sin->sin_addr.s_addr == 0) { if (!(SC2IFP(sc)->if_flags & IFF_UP)) carp_set_state(sc, INIT); if (sc->sc_naddrs) SC2IFP(sc)->if_flags |= IFF_UP; if (sc->sc_carpdev) CARP_SCLOCK(sc); carp_setrun(sc, 0); if (sc->sc_carpdev) CARP_SCUNLOCK(sc); return (0); } /* we have to do it by hands to check we won't match on us */ ia_if = NULL; own = 0; IN_IFADDR_RLOCK(); TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) { /* and, yeah, we need a multicast-capable iface too */ if (ia->ia_ifp != SC2IFP(sc) && (ia->ia_ifp->if_flags & IFF_MULTICAST) && (iaddr & ia->ia_subnetmask) == ia->ia_subnet) { if (!ia_if) ia_if = ia; if (sin->sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr) own++; } } if (!ia_if) { IN_IFADDR_RUNLOCK(); return (EADDRNOTAVAIL); } ia = ia_if; ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(); ifp = ia->ia_ifp; if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 || (imo->imo_multicast_ifp && imo->imo_multicast_ifp != ifp)) { ifa_free(&ia->ia_ifa); return (EADDRNOTAVAIL); } if (imo->imo_num_memberships == 0) { addr.s_addr = htonl(INADDR_CARP_GROUP); if ((imo->imo_membership[0] = in_addmulti(&addr, ifp)) == NULL) { ifa_free(&ia->ia_ifa); return (ENOBUFS); } imo->imo_num_memberships++; imo->imo_multicast_ifp = ifp; imo->imo_multicast_ttl = CARP_DFLTTL; imo->imo_multicast_loop = 0; } if (!ifp->if_carp) { cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); if (!cif) { error = ENOBUFS; goto cleanup; } if ((error = ifpromisc(ifp, 1))) { free(cif, M_CARP); goto cleanup; } CARP_LOCK_INIT(cif); CARP_LOCK(cif); cif->vhif_ifp = ifp; TAILQ_INIT(&cif->vhif_vrs); ifp->if_carp = cif; } else { struct carp_softc *vr; cif = (struct carp_if *)ifp->if_carp; CARP_LOCK(cif); TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) if (vr != sc && vr->sc_vhid == sc->sc_vhid) { CARP_UNLOCK(cif); error = EEXIST; goto cleanup; } } sc->sc_ia = ia; sc->sc_carpdev = ifp; { /* XXX prevent endless loop if already in queue */ struct carp_softc *vr, *after = NULL; int myself = 0; cif = (struct carp_if *)ifp->if_carp; /* XXX: cif should not change, right? So we still hold the lock */ CARP_LOCK_ASSERT(cif); TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) { if (vr == sc) myself = 1; if (vr->sc_vhid < sc->sc_vhid) after = vr; } if (!myself) { /* We're trying to keep things in order */ if (after == NULL) { TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list); } else { TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list); } cif->vhif_nvrs++; } } sc->sc_naddrs++; SC2IFP(sc)->if_flags |= IFF_UP; if (own) sc->sc_advskew = 0; carp_sc_state_locked(sc); carp_setrun(sc, 0); CARP_UNLOCK(cif); ifa_free(&ia->ia_ifa); /* XXXRW: should hold reference for softc. */ return (0); cleanup: in_delmulti(imo->imo_membership[--imo->imo_num_memberships]); ifa_free(&ia->ia_ifa); return (error); } static int carp_del_addr(struct carp_softc *sc, struct sockaddr_in *sin) { int error = 0; if (!--sc->sc_naddrs) { struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp; struct ip_moptions *imo = &sc->sc_imo; CARP_LOCK(cif); callout_stop(&sc->sc_ad_tmo); SC2IFP(sc)->if_flags &= ~IFF_UP; SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; sc->sc_vhid = -1; in_delmulti(imo->imo_membership[--imo->imo_num_memberships]); imo->imo_multicast_ifp = NULL; TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list); if (!--cif->vhif_nvrs) { sc->sc_carpdev->if_carp = NULL; CARP_LOCK_DESTROY(cif); free(cif, M_CARP); } else { CARP_UNLOCK(cif); } } return (error); } #ifdef INET6 static int carp_set_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6) { struct ifnet *ifp; struct carp_if *cif; struct in6_ifaddr *ia, *ia_if; struct ip6_moptions *im6o = &sc->sc_im6o; struct in6_addr in6; int own, error; error = 0; if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { if (!(SC2IFP(sc)->if_flags & IFF_UP)) carp_set_state(sc, INIT); if (sc->sc_naddrs6) SC2IFP(sc)->if_flags |= IFF_UP; if (sc->sc_carpdev) CARP_SCLOCK(sc); carp_setrun(sc, 0); if (sc->sc_carpdev) CARP_SCUNLOCK(sc); return (0); } /* we have to do it by hands to check we won't match on us */ ia_if = NULL; own = 0; IN6_IFADDR_RLOCK(); TAILQ_FOREACH(ia, &V_in6_ifaddrhead, ia_link) { int i; for (i = 0; i < 4; i++) { if ((sin6->sin6_addr.s6_addr32[i] & ia->ia_prefixmask.sin6_addr.s6_addr32[i]) != (ia->ia_addr.sin6_addr.s6_addr32[i] & ia->ia_prefixmask.sin6_addr.s6_addr32[i])) break; } /* and, yeah, we need a multicast-capable iface too */ if (ia->ia_ifp != SC2IFP(sc) && (ia->ia_ifp->if_flags & IFF_MULTICAST) && (i == 4)) { if (!ia_if) ia_if = ia; if (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ia->ia_addr.sin6_addr)) own++; } } if (!ia_if) { IN6_IFADDR_RUNLOCK(); return (EADDRNOTAVAIL); } ia = ia_if; ifa_ref(&ia->ia_ifa); IN6_IFADDR_RUNLOCK(); ifp = ia->ia_ifp; if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0 || (im6o->im6o_multicast_ifp && im6o->im6o_multicast_ifp != ifp)) { ifa_free(&ia->ia_ifa); return (EADDRNOTAVAIL); } if (!sc->sc_naddrs6) { struct in6_multi *in6m; im6o->im6o_multicast_ifp = ifp; /* join CARP multicast address */ bzero(&in6, sizeof(in6)); in6.s6_addr16[0] = htons(0xff02); in6.s6_addr8[15] = 0x12; if (in6_setscope(&in6, ifp, NULL) != 0) goto cleanup; in6m = NULL; error = in6_mc_join(ifp, &in6, NULL, &in6m, 0); if (error) goto cleanup; im6o->im6o_membership[0] = in6m; im6o->im6o_num_memberships++; /* join solicited multicast address */ bzero(&in6, sizeof(in6)); in6.s6_addr16[0] = htons(0xff02); in6.s6_addr32[1] = 0; in6.s6_addr32[2] = htonl(1); in6.s6_addr32[3] = sin6->sin6_addr.s6_addr32[3]; in6.s6_addr8[12] = 0xff; if (in6_setscope(&in6, ifp, NULL) != 0) goto cleanup; in6m = NULL; error = in6_mc_join(ifp, &in6, NULL, &in6m, 0); if (error) goto cleanup; im6o->im6o_membership[1] = in6m; im6o->im6o_num_memberships++; } if (!ifp->if_carp) { cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); if (!cif) { error = ENOBUFS; goto cleanup; } if ((error = ifpromisc(ifp, 1))) { free(cif, M_CARP); goto cleanup; } CARP_LOCK_INIT(cif); CARP_LOCK(cif); cif->vhif_ifp = ifp; TAILQ_INIT(&cif->vhif_vrs); ifp->if_carp = cif; } else { struct carp_softc *vr; cif = (struct carp_if *)ifp->if_carp; CARP_LOCK(cif); TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) if (vr != sc && vr->sc_vhid == sc->sc_vhid) { CARP_UNLOCK(cif); error = EINVAL; goto cleanup; } } sc->sc_ia6 = ia; sc->sc_carpdev = ifp; { /* XXX prevent endless loop if already in queue */ struct carp_softc *vr, *after = NULL; int myself = 0; cif = (struct carp_if *)ifp->if_carp; CARP_LOCK_ASSERT(cif); TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) { if (vr == sc) myself = 1; if (vr->sc_vhid < sc->sc_vhid) after = vr; } if (!myself) { /* We're trying to keep things in order */ if (after == NULL) { TAILQ_INSERT_TAIL(&cif->vhif_vrs, sc, sc_list); } else { TAILQ_INSERT_AFTER(&cif->vhif_vrs, after, sc, sc_list); } cif->vhif_nvrs++; } } sc->sc_naddrs6++; SC2IFP(sc)->if_flags |= IFF_UP; if (own) sc->sc_advskew = 0; carp_sc_state_locked(sc); carp_setrun(sc, 0); CARP_UNLOCK(cif); ifa_free(&ia->ia_ifa); /* XXXRW: should hold reference for softc. */ return (0); cleanup: if (!sc->sc_naddrs6) carp_multicast6_cleanup(sc); ifa_free(&ia->ia_ifa); return (error); } static int carp_del_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6) { int error = 0; if (!--sc->sc_naddrs6) { struct carp_if *cif = (struct carp_if *)sc->sc_carpdev->if_carp; CARP_LOCK(cif); callout_stop(&sc->sc_ad_tmo); SC2IFP(sc)->if_flags &= ~IFF_UP; SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; sc->sc_vhid = -1; carp_multicast6_cleanup(sc); TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list); if (!--cif->vhif_nvrs) { CARP_LOCK_DESTROY(cif); sc->sc_carpdev->if_carp = NULL; free(cif, M_CARP); } else CARP_UNLOCK(cif); } return (error); } #endif /* INET6 */ static int carp_ioctl(struct ifnet *ifp, u_long cmd, caddr_t addr) { struct carp_softc *sc = ifp->if_softc, *vr; struct carpreq carpr; struct ifaddr *ifa; struct ifreq *ifr; struct ifaliasreq *ifra; int locked = 0, error = 0; ifa = (struct ifaddr *)addr; ifra = (struct ifaliasreq *)addr; ifr = (struct ifreq *)addr; switch (cmd) { case SIOCSIFADDR: switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: SC2IFP(sc)->if_flags |= IFF_UP; bcopy(ifa->ifa_addr, ifa->ifa_dstaddr, sizeof(struct sockaddr)); error = carp_set_addr(sc, satosin(ifa->ifa_addr)); break; #endif /* INET */ #ifdef INET6 case AF_INET6: SC2IFP(sc)->if_flags |= IFF_UP; error = carp_set_addr6(sc, satosin6(ifa->ifa_addr)); break; #endif /* INET6 */ default: error = EAFNOSUPPORT; break; } break; case SIOCAIFADDR: switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: SC2IFP(sc)->if_flags |= IFF_UP; bcopy(ifa->ifa_addr, ifa->ifa_dstaddr, sizeof(struct sockaddr)); error = carp_set_addr(sc, satosin(&ifra->ifra_addr)); break; #endif /* INET */ #ifdef INET6 case AF_INET6: SC2IFP(sc)->if_flags |= IFF_UP; error = carp_set_addr6(sc, satosin6(&ifra->ifra_addr)); break; #endif /* INET6 */ default: error = EAFNOSUPPORT; break; } break; case SIOCDIFADDR: switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: error = carp_del_addr(sc, satosin(&ifra->ifra_addr)); break; #endif /* INET */ #ifdef INET6 case AF_INET6: error = carp_del_addr6(sc, satosin6(&ifra->ifra_addr)); break; #endif /* INET6 */ default: error = EAFNOSUPPORT; break; } break; case SIOCSIFFLAGS: if (sc->sc_carpdev) { locked = 1; CARP_SCLOCK(sc); } if (sc->sc_state != INIT && !(ifr->ifr_flags & IFF_UP)) { callout_stop(&sc->sc_ad_tmo); callout_stop(&sc->sc_md_tmo); callout_stop(&sc->sc_md6_tmo); if (sc->sc_state == MASTER) carp_send_ad_locked(sc); carp_set_state(sc, INIT); carp_setrun(sc, 0); } else if (sc->sc_state == INIT && (ifr->ifr_flags & IFF_UP)) { SC2IFP(sc)->if_flags |= IFF_UP; carp_setrun(sc, 0); } break; case SIOCSVH: error = priv_check(curthread, PRIV_NETINET_CARP); if (error) break; if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr))) break; error = 1; if (sc->sc_carpdev) { locked = 1; CARP_SCLOCK(sc); } if (sc->sc_state != INIT && carpr.carpr_state != sc->sc_state) { switch (carpr.carpr_state) { case BACKUP: callout_stop(&sc->sc_ad_tmo); carp_set_state(sc, BACKUP); carp_setrun(sc, 0); carp_setroute(sc, RTM_DELETE); break; case MASTER: carp_master_down_locked(sc); break; default: break; } } if (carpr.carpr_vhid > 0) { if (carpr.carpr_vhid > 255) { error = EINVAL; break; } if (sc->sc_carpdev) { struct carp_if *cif; cif = (struct carp_if *)sc->sc_carpdev->if_carp; TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) if (vr != sc && vr->sc_vhid == carpr.carpr_vhid) { error = EEXIST; break; } if (error == EEXIST) break; } sc->sc_vhid = carpr.carpr_vhid; IF_LLADDR(sc->sc_ifp)[0] = 0; IF_LLADDR(sc->sc_ifp)[1] = 0; IF_LLADDR(sc->sc_ifp)[2] = 0x5e; IF_LLADDR(sc->sc_ifp)[3] = 0; IF_LLADDR(sc->sc_ifp)[4] = 1; IF_LLADDR(sc->sc_ifp)[5] = sc->sc_vhid; error--; } if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) { if (carpr.carpr_advskew >= 255) { error = EINVAL; break; } if (carpr.carpr_advbase > 255) { error = EINVAL; break; } sc->sc_advbase = carpr.carpr_advbase; sc->sc_advskew = carpr.carpr_advskew; error--; } bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); if (error > 0) error = EINVAL; else { error = 0; carp_setrun(sc, 0); } break; case SIOCGVH: /* XXX: lockless read */ bzero(&carpr, sizeof(carpr)); carpr.carpr_state = sc->sc_state; carpr.carpr_vhid = sc->sc_vhid; carpr.carpr_advbase = sc->sc_advbase; carpr.carpr_advskew = sc->sc_advskew; error = priv_check(curthread, PRIV_NETINET_CARP); if (error == 0) bcopy(sc->sc_key, carpr.carpr_key, sizeof(carpr.carpr_key)); error = copyout(&carpr, ifr->ifr_data, sizeof(carpr)); break; default: error = EINVAL; } if (locked) CARP_SCUNLOCK(sc); carp_hmac_prepare(sc); return (error); } /* * XXX: this is looutput. We should eventually use it from there. */ static int carp_looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, struct route *ro) { u_int32_t af; struct rtentry *rt = NULL; M_ASSERTPKTHDR(m); /* check if we have the packet header */ if (ro != NULL) rt = ro->ro_rt; if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { m_freem(m); return (rt->rt_flags & RTF_BLACKHOLE ? 0 : rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); } ifp->if_opackets++; ifp->if_obytes += m->m_pkthdr.len; /* BPF writes need to be handled specially. */ if (dst->sa_family == AF_UNSPEC) { bcopy(dst->sa_data, &af, sizeof(af)); dst->sa_family = af; } #if 1 /* XXX */ switch (dst->sa_family) { case AF_INET: case AF_INET6: case AF_IPX: case AF_APPLETALK: break; default: printf("carp_looutput: af=%d unexpected\n", dst->sa_family); m_freem(m); return (EAFNOSUPPORT); } #endif return(if_simloop(ifp, m, dst->sa_family, 0)); } /* * Start output on carp interface. This function should never be called. */ static void carp_start(struct ifnet *ifp) { #ifdef DEBUG printf("%s: start called\n", ifp->if_xname); #endif } int carp_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa, struct rtentry *rt) { struct m_tag *mtag; struct carp_softc *sc; struct ifnet *carp_ifp; if (!sa) return (0); switch (sa->sa_family) { #ifdef INET case AF_INET: break; #endif /* INET */ #ifdef INET6 case AF_INET6: break; #endif /* INET6 */ default: return (0); } mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); if (mtag == NULL) return (0); bcopy(mtag + 1, &carp_ifp, sizeof(struct ifnet *)); sc = carp_ifp->if_softc; /* Set the source MAC address to Virtual Router MAC Address */ switch (ifp->if_type) { case IFT_ETHER: case IFT_L2VLAN: { struct ether_header *eh; eh = mtod(m, struct ether_header *); eh->ether_shost[0] = 0; eh->ether_shost[1] = 0; eh->ether_shost[2] = 0x5e; eh->ether_shost[3] = 0; eh->ether_shost[4] = 1; eh->ether_shost[5] = sc->sc_vhid; } break; case IFT_FDDI: { struct fddi_header *fh; fh = mtod(m, struct fddi_header *); fh->fddi_shost[0] = 0; fh->fddi_shost[1] = 0; fh->fddi_shost[2] = 0x5e; fh->fddi_shost[3] = 0; fh->fddi_shost[4] = 1; fh->fddi_shost[5] = sc->sc_vhid; } break; case IFT_ISO88025: { struct iso88025_header *th; th = mtod(m, struct iso88025_header *); th->iso88025_shost[0] = 3; th->iso88025_shost[1] = 0; th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1); th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1); th->iso88025_shost[4] = 0; th->iso88025_shost[5] = 0; } break; default: printf("%s: carp is not supported for this interface type\n", ifp->if_xname); return (EOPNOTSUPP); } return (0); } static void carp_set_state(struct carp_softc *sc, int state) { int link_state; if (sc->sc_carpdev) CARP_SCLOCK_ASSERT(sc); if (sc->sc_state == state) return; sc->sc_state = state; switch (state) { case BACKUP: link_state = LINK_STATE_DOWN; break; case MASTER: link_state = LINK_STATE_UP; break; default: link_state = LINK_STATE_UNKNOWN; break; } if_link_state_change(SC2IFP(sc), link_state); } void carp_carpdev_state(void *v) { struct carp_if *cif = v; CARP_LOCK(cif); carp_carpdev_state_locked(cif); CARP_UNLOCK(cif); } static void carp_carpdev_state_locked(struct carp_if *cif) { struct carp_softc *sc; TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) carp_sc_state_locked(sc); } static void carp_sc_state_locked(struct carp_softc *sc) { CARP_SCLOCK_ASSERT(sc); if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || !(sc->sc_carpdev->if_flags & IFF_UP)) { sc->sc_flags_backup = SC2IFP(sc)->if_flags; SC2IFP(sc)->if_flags &= ~IFF_UP; SC2IFP(sc)->if_drv_flags &= ~IFF_DRV_RUNNING; callout_stop(&sc->sc_ad_tmo); callout_stop(&sc->sc_md_tmo); callout_stop(&sc->sc_md6_tmo); carp_set_state(sc, INIT); carp_setrun(sc, 0); if (!sc->sc_suppress) { carp_suppress_preempt++; if (carp_suppress_preempt == 1) { CARP_SCUNLOCK(sc); carp_send_ad_all(); CARP_SCLOCK(sc); } } sc->sc_suppress = 1; } else { SC2IFP(sc)->if_flags |= sc->sc_flags_backup; carp_set_state(sc, INIT); carp_setrun(sc, 0); if (sc->sc_suppress) carp_suppress_preempt--; sc->sc_suppress = 0; } return; } static int carp_modevent(module_t mod, int type, void *data) { switch (type) { case MOD_LOAD: if_detach_event_tag = EVENTHANDLER_REGISTER(ifnet_departure_event, carp_ifdetach, NULL, EVENTHANDLER_PRI_ANY); if (if_detach_event_tag == NULL) return (ENOMEM); mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); LIST_INIT(&carpif_list); if_clone_attach(&carp_cloner); break; case MOD_UNLOAD: EVENTHANDLER_DEREGISTER(ifnet_departure_event, if_detach_event_tag); if_clone_detach(&carp_cloner); mtx_destroy(&carp_mtx); break; default: return (EINVAL); } return (0); } static moduledata_t carp_mod = { "carp", carp_modevent, 0 }; DECLARE_MODULE(carp, carp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);