/* $NetBSD: ip_carp.c,v 1.44 2010/08/11 11:06:42 pooka Exp $ */ /* $OpenBSD: ip_carp.c,v 1.113 2005/11/04 08:11:54 mcbride Exp $ */ /* * 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 "opt_inet.h" #include __KERNEL_RCSID(0, "$NetBSD: ip_carp.c,v 1.44 2010/08/11 11:06:42 pooka Exp $"); /* * TODO: * - iface reconfigure * - support for hardware checksum calculations; * */ #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 #if NFDDI > 0 #include #endif #if NTOKEN > 0 #include #endif #ifdef INET #include #include #include #include #include #include #endif #ifdef INET6 #include #include #include #include #include #endif #include #include #include struct carp_mc_entry { LIST_ENTRY(carp_mc_entry) mc_entries; union { struct ether_multi *mcu_enm; } mc_u; struct sockaddr_storage mc_addr; }; #define mc_enm mc_u.mcu_enm struct carp_softc { struct ethercom sc_ac; #define sc_if sc_ac.ec_if #define sc_carpdev sc_ac.ec_if.if_carpdev int ah_cookie; int lh_cookie; struct ip_moptions sc_imo; #ifdef INET6 struct ip6_moptions sc_im6o; #endif /* INET6 */ TAILQ_ENTRY(carp_softc) sc_list; enum { INIT = 0, BACKUP, MASTER } sc_state; int sc_suppress; int sc_bow_out; 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; u_int32_t sc_hashkey[2]; struct callout sc_ad_tmo; /* advertisement timeout */ struct callout sc_md_tmo; /* master down timeout */ struct callout sc_md6_tmo; /* master down timeout */ LIST_HEAD(__carp_mchead, carp_mc_entry) carp_mc_listhead; }; int carp_suppress_preempt = 0; int carp_opts[CARPCTL_MAXID] = { 0, 1, 0, 0, 0 }; /* XXX for now */ static percpu_t *carpstat_percpu; #define CARP_STATINC(x) _NET_STATINC(carpstat_percpu, x) struct carp_if { TAILQ_HEAD(, carp_softc) vhif_vrs; int vhif_nvrs; struct ifnet *vhif_ifp; }; #define CARP_LOG(sc, s) \ if (carp_opts[CARPCTL_LOG]) { \ if (sc) \ log(LOG_INFO, "%s: ", \ (sc)->sc_if.if_xname); \ else \ log(LOG_INFO, "carp: "); \ addlog s; \ addlog("\n"); \ } void carp_hmac_prepare(struct carp_softc *); void carp_hmac_generate(struct carp_softc *, u_int32_t *, unsigned char *); int carp_hmac_verify(struct carp_softc *, u_int32_t *, unsigned char *); void carp_setroute(struct carp_softc *, int); void carp_proto_input_c(struct mbuf *, struct carp_header *, sa_family_t); void carpattach(int); void carpdetach(struct carp_softc *); int carp_prepare_ad(struct mbuf *, struct carp_softc *, struct carp_header *); void carp_send_ad_all(void); void carp_send_ad(void *); void carp_send_arp(struct carp_softc *); void carp_master_down(void *); int carp_ioctl(struct ifnet *, u_long, void *); void carp_start(struct ifnet *); void carp_setrun(struct carp_softc *, sa_family_t); void carp_set_state(struct carp_softc *, int); int carp_addrcount(struct carp_if *, struct in_ifaddr *, int); enum { CARP_COUNT_MASTER, CARP_COUNT_RUNNING }; void carp_multicast_cleanup(struct carp_softc *); int carp_set_ifp(struct carp_softc *, struct ifnet *); void carp_set_enaddr(struct carp_softc *); void carp_addr_updated(void *); u_int32_t carp_hash(struct carp_softc *, u_char *); int carp_set_addr(struct carp_softc *, struct sockaddr_in *); int carp_join_multicast(struct carp_softc *); #ifdef INET6 void carp_send_na(struct carp_softc *); int carp_set_addr6(struct carp_softc *, struct sockaddr_in6 *); int carp_join_multicast6(struct carp_softc *); #endif int carp_clone_create(struct if_clone *, int); int carp_clone_destroy(struct ifnet *); int carp_ether_addmulti(struct carp_softc *, struct ifreq *); int carp_ether_delmulti(struct carp_softc *, struct ifreq *); void carp_ether_purgemulti(struct carp_softc *); static void sysctl_net_inet_carp_setup(struct sysctllog **); struct if_clone carp_cloner = IF_CLONE_INITIALIZER("carp", carp_clone_create, carp_clone_destroy); static __inline u_int16_t carp_cksum(struct mbuf *m, int len) { return (in_cksum(m, len)); } void carp_hmac_prepare(struct carp_softc *sc) { u_int8_t carp_version = CARP_VERSION, type = CARP_ADVERTISEMENT; u_int8_t vhid = sc->sc_vhid & 0xff; SHA1_CTX sha1ctx; u_int32_t kmd[5]; struct ifaddr *ifa; int i, found; struct in_addr last, cur, in; #ifdef INET6 struct in6_addr last6, cur6, in6; #endif /* INET6 */ /* compute ipad from key */ memset(sc->sc_pad, 0, sizeof(sc->sc_pad)); memcpy(sc->sc_pad, sc->sc_key, 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 *)&carp_version, sizeof(carp_version)); SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); /* generate a key for the arpbalance hash, before the vhid is hashed */ memcpy(&sha1ctx, &sc->sc_sha1, sizeof(sha1ctx)); SHA1Final((unsigned char *)kmd, &sha1ctx); sc->sc_hashkey[0] = kmd[0] ^ kmd[1]; sc->sc_hashkey[1] = kmd[2] ^ kmd[3]; /* the rest of the precomputation */ SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); /* Hash the addresses from smallest to largest, not interface order */ #ifdef INET cur.s_addr = 0; do { found = 0; last = cur; cur.s_addr = 0xffffffff; IFADDR_FOREACH(ifa, &sc->sc_if) { 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 (found) SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); } while (found); #endif /* INET */ #ifdef INET6 memset(&cur6, 0x00, sizeof(cur6)); do { found = 0; last6 = cur6; memset(&cur6, 0xff, sizeof(cur6)); IFADDR_FOREACH(ifa, &sc->sc_if) { in6 = ifatoia6(ifa)->ia_addr.sin6_addr; if (IN6_IS_ADDR_LINKLOCAL(&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 (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; } 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 */ memcpy(&sha1ctx, &sc->sc_sha1, 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); } int carp_hmac_verify(struct carp_softc *sc, u_int32_t counter[2], unsigned char md[20]) { unsigned char md2[20]; carp_hmac_generate(sc, counter, md2); return (memcmp(md, md2, sizeof(md2))); } void carp_setroute(struct carp_softc *sc, int cmd) { struct ifaddr *ifa; int s; s = splsoftnet(); IFADDR_FOREACH(ifa, &sc->sc_if) { switch (ifa->ifa_addr->sa_family) { case AF_INET: { int count = 0; struct rtentry *rt; int hr_otherif, nr_ourif; /* * Avoid screwing with the routes if there are other * carp interfaces which are master and have the same * address. */ if (sc->sc_carpdev != NULL && sc->sc_carpdev->if_carp != NULL) { 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)) continue; } /* Remove the existing host route, if any */ rtrequest(RTM_DELETE, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, RTF_HOST, NULL); rt = NULL; (void)rtrequest(RTM_GET, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, RTF_HOST, &rt); hr_otherif = (rt && rt->rt_ifp != &sc->sc_if && rt->rt_flags & (RTF_CLONING|RTF_CLONED)); if (rt != NULL) { RTFREE(rt); rt = NULL; } /* Check for a network route on our interface */ rt = NULL; (void)rtrequest(RTM_GET, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, 0, &rt); nr_ourif = (rt && rt->rt_ifp == &sc->sc_if); switch (cmd) { case RTM_ADD: if (hr_otherif) { ifa->ifa_rtrequest = NULL; ifa->ifa_flags &= ~RTF_CLONING; rtrequest(RTM_ADD, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, RTF_UP | RTF_HOST, NULL); } if (!hr_otherif || nr_ourif || !rt) { if (nr_ourif && !(rt->rt_flags & RTF_CLONING)) rtrequest(RTM_DELETE, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, 0, NULL); ifa->ifa_rtrequest = arp_rtrequest; ifa->ifa_flags |= RTF_CLONING; if (rtrequest(RTM_ADD, ifa->ifa_addr, ifa->ifa_addr, ifa->ifa_netmask, 0, NULL) == 0) ifa->ifa_flags |= IFA_ROUTE; } break; case RTM_DELETE: break; default: break; } if (rt != NULL) { RTFREE(rt); rt = NULL; } break; } #ifdef INET6 case AF_INET6: if (cmd == RTM_ADD) in6_ifaddloop(ifa); else in6_ifremloop(ifa); break; #endif /* INET6 */ default: break; } } splx(s); } /* * 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_proto_input(struct mbuf *m, ...) { struct ip *ip = mtod(m, struct ip *); struct carp_softc *sc = NULL; struct carp_header *ch; int iplen, len, hlen; va_list ap; va_start(ap, m); hlen = va_arg(ap, int); va_end(ap); CARP_STATINC(CARP_STAT_IPACKETS); if (!carp_opts[CARPCTL_ALLOW]) { m_freem(m); return; } /* check if received on a valid carp interface */ if (m->m_pkthdr.rcvif->if_type != IFT_CARP) { CARP_STATINC(CARP_STAT_BADIF); CARP_LOG(sc, ("packet received on non-carp interface: %s", m->m_pkthdr.rcvif->if_xname)); m_freem(m); return; } /* verify that the IP TTL is 255. */ if (ip->ip_ttl != CARP_DFLTTL) { CARP_STATINC(CARP_STAT_BADTTL); CARP_LOG(sc, ("received ttl %d != %d on %s", ip->ip_ttl, CARP_DFLTTL, m->m_pkthdr.rcvif->if_xname)); m_freem(m); return; } /* * verify that the received packet length is * equal to the CARP header */ iplen = ip->ip_hl << 2; len = iplen + sizeof(*ch); if (len > m->m_pkthdr.len) { CARP_STATINC(CARP_STAT_BADLEN); CARP_LOG(sc, ("packet too short %d on %s", m->m_pkthdr.len, m->m_pkthdr.rcvif->if_xname)); m_freem(m); return; } if ((m = m_pullup(m, len)) == NULL) { CARP_STATINC(CARP_STAT_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)) { CARP_STATINC(CARP_STAT_BADSUM); CARP_LOG(sc, ("checksum failed on %s", m->m_pkthdr.rcvif->if_xname)); m_freem(m); return; } m->m_data -= iplen; carp_proto_input_c(m, ch, AF_INET); } #ifdef INET6 int carp6_proto_input(struct mbuf **mp, int *offp, int proto) { struct mbuf *m = *mp; struct carp_softc *sc = NULL; struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct carp_header *ch; u_int len; CARP_STATINC(CARP_STAT_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_type != IFT_CARP) { CARP_STATINC(CARP_STAT_BADIF); CARP_LOG(sc, ("packet received on non-carp interface: %s", 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) { CARP_STATINC(CARP_STAT_BADTTL); CARP_LOG(sc, ("received ttl %d != %d on %s", ip6->ip6_hlim, CARP_DFLTTL, 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) { CARP_STATINC(CARP_STAT_BADLEN); CARP_LOG(sc, ("packet size %u too small", len)); return (IPPROTO_DONE); } /* verify the CARP checksum */ m->m_data += *offp; if (carp_cksum(m, sizeof(*ch))) { CARP_STATINC(CARP_STAT_BADSUM); CARP_LOG(sc, ("checksum failed, on %s", m->m_pkthdr.rcvif->if_xname)); m_freem(m); return (IPPROTO_DONE); } m->m_data -= *offp; carp_proto_input_c(m, ch, AF_INET6); return (IPPROTO_DONE); } #endif /* INET6 */ void carp_proto_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) { struct carp_softc *sc; u_int64_t tmp_counter; struct timeval sc_tv, ch_tv; TAILQ_FOREACH(sc, &((struct carp_if *) m->m_pkthdr.rcvif->if_carpdev->if_carp)->vhif_vrs, sc_list) if (sc->sc_vhid == ch->carp_vhid) break; if (!sc || (sc->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) { CARP_STATINC(CARP_STAT_BADVHID); m_freem(m); return; } /* * Check if our own advertisement was duplicated * from a non simplex interface. * XXX If there is no address on our physical interface * there is no way to distinguish our ads from the ones * another carp host might have sent us. */ if ((sc->sc_carpdev->if_flags & IFF_SIMPLEX) == 0) { struct sockaddr sa; struct ifaddr *ifa; memset(&sa, 0, sizeof(sa)); sa.sa_family = af; ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev); if (ifa && af == AF_INET) { struct ip *ip = mtod(m, struct ip *); if (ip->ip_src.s_addr == ifatoia(ifa)->ia_addr.sin_addr.s_addr) { m_freem(m); return; } } #ifdef INET6 if (ifa && af == AF_INET6) { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); struct in6_addr in6_src, in6_found; in6_src = ip6->ip6_src; in6_found = ifatoia6(ifa)->ia_addr.sin6_addr; if (IN6_IS_ADDR_LINKLOCAL(&in6_src)) in6_src.s6_addr16[1] = 0; if (IN6_IS_ADDR_LINKLOCAL(&in6_found)) in6_found.s6_addr16[1] = 0; if (IN6_ARE_ADDR_EQUAL(&in6_src, &in6_found)) { m_freem(m); return; } } #endif /* INET6 */ } nanotime(&sc->sc_if.if_lastchange); sc->sc_if.if_ipackets++; sc->sc_if.if_ibytes += m->m_pkthdr.len; /* verify the CARP version. */ if (ch->carp_version != CARP_VERSION) { CARP_STATINC(CARP_STAT_BADVER); sc->sc_if.if_ierrors++; CARP_LOG(sc, ("invalid version %d != %d", ch->carp_version, CARP_VERSION)); m_freem(m); return; } /* verify the hash */ if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { CARP_STATINC(CARP_STAT_BADAUTH); sc->sc_if.if_ierrors++; CARP_LOG(sc, ("incorrect hash")); 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 backup who's going to * be more frequent than us, go into BACKUP state. */ if (timercmp(&sc_tv, &ch_tv, >) || timercmp(&sc_tv, &ch_tv, ==)) { callout_stop(&sc->sc_ad_tmo); CARP_LOG(sc, ("MASTER -> BACKUP (more frequent advertisement received)")); 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] && timercmp(&sc_tv, &ch_tv, <)) { CARP_LOG(sc, ("BACKUP -> MASTER (preempting a slower master)")); carp_master_down(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 (timercmp(&sc_tv, &ch_tv, <)) { CARP_LOG(sc, ("BACKUP -> MASTER (master timed out)")); carp_master_down(sc); break; } /* * Otherwise, we reset the counter and wait for the next * advertisement. */ carp_setrun(sc, af); break; } m_freem(m); return; } /* * Interface side of the CARP implementation. */ /* ARGSUSED */ void carpattach(int n) { if_clone_attach(&carp_cloner); carpstat_percpu = percpu_alloc(sizeof(uint64_t) * CARP_NSTATS); } int carp_clone_create(struct if_clone *ifc, int unit) { extern int ifqmaxlen; struct carp_softc *sc; struct ifnet *ifp; sc = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT|M_ZERO); if (!sc) return (ENOMEM); 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; #ifdef INET6 sc->sc_im6o.im6o_multicast_hlim = CARP_DFLTTL; #endif /* INET6 */ callout_init(&sc->sc_ad_tmo, 0); callout_init(&sc->sc_md_tmo, 0); callout_init(&sc->sc_md6_tmo, 0); callout_setfunc(&sc->sc_ad_tmo, carp_send_ad, sc); callout_setfunc(&sc->sc_md_tmo, carp_master_down, sc); callout_setfunc(&sc->sc_md6_tmo, carp_master_down, sc); LIST_INIT(&sc->carp_mc_listhead); ifp = &sc->sc_if; ifp->if_softc = sc; snprintf(ifp->if_xname, sizeof ifp->if_xname, "%s%d", ifc->ifc_name, unit); ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; ifp->if_ioctl = carp_ioctl; ifp->if_start = carp_start; ifp->if_output = carp_output; ifp->if_type = IFT_CARP; ifp->if_addrlen = ETHER_ADDR_LEN; ifp->if_hdrlen = ETHER_HDR_LEN; ifp->if_mtu = ETHERMTU; IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen); IFQ_SET_READY(&ifp->if_snd); if_attach(ifp); if_alloc_sadl(ifp); ifp->if_broadcastaddr = etherbroadcastaddr; carp_set_enaddr(sc); LIST_INIT(&sc->sc_ac.ec_multiaddrs); bpf_attach(ifp, DLT_EN10MB, ETHER_HDR_LEN); return (0); } int carp_clone_destroy(struct ifnet *ifp) { struct carp_softc *sc = ifp->if_softc; carpdetach(ifp->if_softc); ether_ifdetach(ifp); if_detach(ifp); callout_destroy(&sc->sc_ad_tmo); callout_destroy(&sc->sc_md_tmo); callout_destroy(&sc->sc_md6_tmo); free(ifp->if_softc, M_DEVBUF); return (0); } void carpdetach(struct carp_softc *sc) { struct carp_if *cif; int s; 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); sc->sc_if.if_flags &= ~IFF_UP; carp_setrun(sc, 0); carp_multicast_cleanup(sc); s = splnet(); if (sc->sc_carpdev != NULL) { /* XXX linkstatehook removal */ cif = (struct carp_if *)sc->sc_carpdev->if_carp; TAILQ_REMOVE(&cif->vhif_vrs, sc, sc_list); if (!--cif->vhif_nvrs) { ifpromisc(sc->sc_carpdev, 0); sc->sc_carpdev->if_carp = NULL; free(cif, M_IFADDR); } } sc->sc_carpdev = NULL; splx(s); } /* Detach an interface from the carp. */ void carp_ifdetach(struct ifnet *ifp) { struct carp_softc *sc, *nextsc; struct carp_if *cif = (struct carp_if *)ifp->if_carp; for (sc = TAILQ_FIRST(&cif->vhif_vrs); sc; sc = nextsc) { nextsc = TAILQ_NEXT(sc, sc_list); carpdetach(sc); } } int carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) { 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); return (0); } void carp_send_ad_all(void) { struct ifnet *ifp; struct carp_if *cif; struct carp_softc *vh; TAILQ_FOREACH(ifp, &ifnet, if_list) { if (ifp->if_carp == NULL || ifp->if_type == IFT_CARP) continue; cif = (struct carp_if *)ifp->if_carp; TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { if ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) == (IFF_UP|IFF_RUNNING) && vh->sc_state == MASTER) carp_send_ad(vh); } } } void carp_send_ad(void *v) { struct carp_header ch; struct timeval tv; struct carp_softc *sc = v; struct carp_header *ch_ptr; struct mbuf *m; int error, len, advbase, advskew, s; struct ifaddr *ifa; struct sockaddr sa; s = splsoftnet(); advbase = advskew = 0; /* Sssssh compiler */ if (sc->sc_carpdev == NULL) { sc->sc_if.if_oerrors++; goto retry_later; } /* bow out if we've gone to backup (the carp interface is going down) */ if (sc->sc_bow_out) { sc->sc_bow_out = 0; 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_naddrs) { struct ip *ip; MGETHDR(m, M_DONTWAIT, MT_HEADER); if (m == NULL) { sc->sc_if.if_oerrors++; CARP_STATINC(CARP_STAT_ONOMEM); /* XXX maybe less ? */ goto retry_later; } 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 = htons(len); ip->ip_id = 0; /* no need for id, we don't support fragments */ ip->ip_off = htons(IP_DF); ip->ip_ttl = CARP_DFLTTL; ip->ip_p = IPPROTO_CARP; ip->ip_sum = 0; memset(&sa, 0, sizeof(sa)); sa.sa_family = AF_INET; ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev); if (ifa == NULL) ip->ip_src.s_addr = 0; else ip->ip_src.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; ip->ip_dst.s_addr = INADDR_CARP_GROUP; ch_ptr = (struct carp_header *)(&ip[1]); memcpy(ch_ptr, &ch, sizeof(ch)); if (carp_prepare_ad(m, sc, ch_ptr)) goto retry_later; m->m_data += sizeof(*ip); ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip)); m->m_data -= sizeof(*ip); nanotime(&sc->sc_if.if_lastchange); sc->sc_if.if_opackets++; sc->sc_if.if_obytes += len; CARP_STATINC(CARP_STAT_OPACKETS); error = ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_imo, NULL); if (error) { if (error == ENOBUFS) CARP_STATINC(CARP_STAT_ONOMEM); else CARP_LOG(sc, ("ip_output failed: %d", error)); sc->sc_if.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_send_ad_all(); } 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_naddrs6) { struct ip6_hdr *ip6; MGETHDR(m, M_DONTWAIT, MT_HEADER); if (m == NULL) { sc->sc_if.if_oerrors++; CARP_STATINC(CARP_STAT_ONOMEM); /* XXX maybe less ? */ goto retry_later; } 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 *); memset(ip6, 0, sizeof(*ip6)); ip6->ip6_vfc |= IPV6_VERSION; ip6->ip6_hlim = CARP_DFLTTL; ip6->ip6_nxt = IPPROTO_CARP; /* set the source address */ memset(&sa, 0, sizeof(sa)); sa.sa_family = AF_INET6; ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev); if (ifa == NULL) /* This should never happen with IPv6 */ memset(&ip6->ip6_src, 0, sizeof(struct in6_addr)); else bcopy(ifatoia6(ifa)->ia_addr.sin6_addr.s6_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) { sc->sc_if.if_oerrors++; m_freem(m); CARP_LOG(sc, ("in6_setscope failed")); goto retry_later; } ch_ptr = (struct carp_header *)(&ip6[1]); memcpy(ch_ptr, &ch, sizeof(ch)); if (carp_prepare_ad(m, sc, ch_ptr)) goto retry_later; m->m_data += sizeof(*ip6); ch_ptr->carp_cksum = carp_cksum(m, len - sizeof(*ip6)); m->m_data -= sizeof(*ip6); nanotime(&sc->sc_if.if_lastchange); sc->sc_if.if_opackets++; sc->sc_if.if_obytes += len; CARP_STATINC(CARP_STAT_OPACKETS6); error = ip6_output(m, NULL, NULL, 0, &sc->sc_im6o, NULL, NULL); if (error) { if (error == ENOBUFS) CARP_STATINC(CARP_STAT_ONOMEM); else CARP_LOG(sc, ("ip6_output failed: %d", error)); sc->sc_if.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_send_ad_all(); } 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 */ retry_later: splx(s); if (advbase != 255 || advskew != 255) callout_schedule(&sc->sc_ad_tmo, tvtohz(&tv)); } /* * Broadcast a gratuitous ARP request containing * the virtual router MAC address for each IP address * associated with the virtual router. */ void carp_send_arp(struct carp_softc *sc) { struct ifaddr *ifa; struct in_addr *in; int s = splsoftnet(); IFADDR_FOREACH(ifa, &sc->sc_if) { if (ifa->ifa_addr->sa_family != AF_INET) continue; in = &ifatoia(ifa)->ia_addr.sin_addr; arprequest(sc->sc_carpdev, in, in, CLLADDR(sc->sc_if.if_sadl)); /* XXX: why does this need to delay? */ kpause("carpdel", false, MAX(1, mstohz(1)), NULL); } splx(s); } #ifdef INET6 void carp_send_na(struct carp_softc *sc) { struct ifaddr *ifa; struct in6_addr *in6; static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; int s = splsoftnet(); IFADDR_FOREACH(ifa, &sc->sc_if) { 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); /* XXX: why does this need to delay? */ kpause("carpdel6", false, MAX(1, mstohz(1)), NULL); } splx(s); } #endif /* INET6 */ /* * Based on bridge_hash() in if_bridge.c */ #define mix(a,b,c) \ do { \ a -= b; a -= c; a ^= (c >> 13); \ b -= c; b -= a; b ^= (a << 8); \ c -= a; c -= b; c ^= (b >> 13); \ a -= b; a -= c; a ^= (c >> 12); \ b -= c; b -= a; b ^= (a << 16); \ c -= a; c -= b; c ^= (b >> 5); \ a -= b; a -= c; a ^= (c >> 3); \ b -= c; b -= a; b ^= (a << 10); \ c -= a; c -= b; c ^= (b >> 15); \ } while (0) u_int32_t carp_hash(struct carp_softc *sc, u_char *src) { u_int32_t a = 0x9e3779b9, b = sc->sc_hashkey[0], c = sc->sc_hashkey[1]; c += sc->sc_key[3] << 24; c += sc->sc_key[2] << 16; c += sc->sc_key[1] << 8; c += sc->sc_key[0]; b += src[5] << 8; b += src[4]; a += src[3] << 24; a += src[2] << 16; a += src[1] << 8; a += src[0]; mix(a, b, c); return (c); } int carp_addrcount(struct carp_if *cif, struct in_ifaddr *ia, int type) { struct carp_softc *vh; struct ifaddr *ifa; int count = 0; TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { if ((type == CARP_COUNT_RUNNING && (vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) == (IFF_UP|IFF_RUNNING)) || (type == CARP_COUNT_MASTER && vh->sc_state == MASTER)) { IFADDR_FOREACH(ifa, &vh->sc_if) { if (ifa->ifa_addr->sa_family == AF_INET && ia->ia_addr.sin_addr.s_addr == ifatoia(ifa)->ia_addr.sin_addr.s_addr) count++; } } } return (count); } int carp_iamatch(struct in_ifaddr *ia, u_char *src, u_int32_t *count, u_int32_t index) { struct carp_softc *sc = ia->ia_ifp->if_softc; if (carp_opts[CARPCTL_ARPBALANCE]) { /* * 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 the elegible carp interfaces with this address */ if (*count == 0) *count = carp_addrcount( (struct carp_if *)ia->ia_ifp->if_carpdev->if_carp, ia, CARP_COUNT_RUNNING); /* This should never happen, but... */ if (*count == 0) return (0); if (carp_hash(sc, src) % *count == index - 1 && sc->sc_state == MASTER) { return (1); } } else { if (sc->sc_state == MASTER) return (1); } 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; TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { IFADDR_FOREACH(ifa, &vh->sc_if) { if (IN6_ARE_ADDR_EQUAL(taddr, &ifatoia6(ifa)->ia_addr.sin6_addr) && ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) == (IFF_UP|IFF_RUNNING)) && vh->sc_state == MASTER) return (ifa); } } return (NULL); } #endif /* INET6 */ struct ifnet * carp_ourether(void *v, struct ether_header *eh, u_char iftype, int src) { struct carp_if *cif = (struct carp_if *)v; struct carp_softc *vh; u_int8_t *ena; if (src) ena = (u_int8_t *)&eh->ether_shost; else ena = (u_int8_t *)&eh->ether_dhost; switch (iftype) { case IFT_ETHER: case IFT_FDDI: if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) return (NULL); break; case IFT_ISO88025: if (ena[0] != 3 || ena[1] || ena[4] || ena[5]) return (NULL); break; default: return (NULL); break; } TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) if ((vh->sc_if.if_flags & (IFF_UP|IFF_RUNNING)) == (IFF_UP|IFF_RUNNING) && vh->sc_state == MASTER && !memcmp(ena, CLLADDR(vh->sc_if.if_sadl), ETHER_ADDR_LEN)) { return (&vh->sc_if); } return (NULL); } int carp_input(struct mbuf *m, u_int8_t *shost, u_int8_t *dhost, u_int16_t etype) { struct ether_header eh; struct carp_if *cif = (struct carp_if *)m->m_pkthdr.rcvif->if_carp; struct ifnet *ifp; memcpy(&eh.ether_shost, shost, sizeof(eh.ether_shost)); memcpy(&eh.ether_dhost, dhost, sizeof(eh.ether_dhost)); eh.ether_type = etype; if (m->m_flags & (M_BCAST|M_MCAST)) { struct carp_softc *vh; struct mbuf *m0; /* * XXX Should really check the list of multicast addresses * for each CARP interface _before_ copying. */ TAILQ_FOREACH(vh, &cif->vhif_vrs, sc_list) { m0 = m_copym(m, 0, M_COPYALL, M_DONTWAIT); if (m0 == NULL) continue; m0->m_pkthdr.rcvif = &vh->sc_if; ether_input(&vh->sc_if, m0); } return (1); } ifp = carp_ourether(cif, &eh, m->m_pkthdr.rcvif->if_type, 0); if (ifp == NULL) { return (1); } m->m_pkthdr.rcvif = ifp; bpf_mtap(ifp, m); ifp->if_ipackets++; ether_input(ifp, m); return (0); } void carp_master_down(void *v) { struct carp_softc *sc = v; switch (sc->sc_state) { case INIT: printf("%s: master_down event in INIT state\n", sc->sc_if.if_xname); break; case MASTER: break; case BACKUP: CARP_LOG(sc, ("INIT -> MASTER (preempting)")); carp_set_state(sc, MASTER); carp_send_ad(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. */ void carp_setrun(struct carp_softc *sc, sa_family_t af) { struct timeval tv; if (sc->sc_carpdev == NULL) { sc->sc_if.if_flags &= ~IFF_RUNNING; carp_set_state(sc, INIT); return; } if (sc->sc_if.if_flags & IFF_UP && sc->sc_vhid > 0 && (sc->sc_naddrs || sc->sc_naddrs6) && !sc->sc_suppress) { sc->sc_if.if_flags |= IFF_RUNNING; } else { sc->sc_if.if_flags &= ~IFF_RUNNING; carp_setroute(sc, RTM_DELETE); return; } switch (sc->sc_state) { case INIT: 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_schedule(&sc->sc_md_tmo, tvtohz(&tv)); break; #endif /* INET */ #ifdef INET6 case AF_INET6: callout_schedule(&sc->sc_md6_tmo, tvtohz(&tv)); break; #endif /* INET6 */ default: if (sc->sc_naddrs) callout_schedule(&sc->sc_md_tmo, tvtohz(&tv)); if (sc->sc_naddrs6) callout_schedule(&sc->sc_md6_tmo, tvtohz(&tv)); break; } break; case MASTER: tv.tv_sec = sc->sc_advbase; tv.tv_usec = sc->sc_advskew * 1000000 / 256; callout_schedule(&sc->sc_ad_tmo, tvtohz(&tv)); break; } } void carp_multicast_cleanup(struct carp_softc *sc) { struct ip_moptions *imo = &sc->sc_imo; #ifdef INET6 struct ip6_moptions *im6o = &sc->sc_im6o; #endif 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; } } imo->imo_num_memberships = 0; imo->imo_multicast_ifp = NULL; #ifdef INET6 while (!LIST_EMPTY(&im6o->im6o_memberships)) { struct in6_multi_mship *imm = LIST_FIRST(&im6o->im6o_memberships); LIST_REMOVE(imm, i6mm_chain); in6_leavegroup(imm); } im6o->im6o_multicast_ifp = NULL; #endif /* And any other multicast memberships */ carp_ether_purgemulti(sc); } int carp_set_ifp(struct carp_softc *sc, struct ifnet *ifp) { struct carp_if *cif, *ncif = NULL; struct carp_softc *vr, *after = NULL; int myself = 0, error = 0; int s; if (ifp == sc->sc_carpdev) return (0); if (ifp != NULL) { if ((ifp->if_flags & IFF_MULTICAST) == 0) return (EADDRNOTAVAIL); if (ifp->if_type == IFT_CARP) return (EINVAL); if (ifp->if_carp == NULL) { ncif = malloc(sizeof(*cif), M_IFADDR, M_NOWAIT); if (ncif == NULL) return (ENOBUFS); if ((error = ifpromisc(ifp, 1))) { free(ncif, M_IFADDR); return (error); } ncif->vhif_ifp = ifp; TAILQ_INIT(&ncif->vhif_vrs); } else { cif = (struct carp_if *)ifp->if_carp; TAILQ_FOREACH(vr, &cif->vhif_vrs, sc_list) if (vr != sc && vr->sc_vhid == sc->sc_vhid) return (EINVAL); } /* detach from old interface */ if (sc->sc_carpdev != NULL) carpdetach(sc); /* join multicast groups */ if (sc->sc_naddrs < 0 && (error = carp_join_multicast(sc)) != 0) { if (ncif != NULL) free(ncif, M_IFADDR); return (error); } #ifdef INET6 if (sc->sc_naddrs6 < 0 && (error = carp_join_multicast6(sc)) != 0) { if (ncif != NULL) free(ncif, M_IFADDR); carp_multicast_cleanup(sc); return (error); } #endif /* attach carp interface to physical interface */ if (ncif != NULL) ifp->if_carp = (void *)ncif; sc->sc_carpdev = ifp; cif = (struct carp_if *)ifp->if_carp; 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++; } if (sc->sc_naddrs || sc->sc_naddrs6) sc->sc_if.if_flags |= IFF_UP; carp_set_enaddr(sc); s = splnet(); /* XXX linkstatehooks establish */ carp_carpdev_state(ifp); splx(s); } else { carpdetach(sc); sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING); } return (0); } void carp_set_enaddr(struct carp_softc *sc) { uint8_t enaddr[ETHER_ADDR_LEN]; if (sc->sc_carpdev && sc->sc_carpdev->if_type == IFT_ISO88025) { enaddr[0] = 3; enaddr[1] = 0; enaddr[2] = 0x40 >> (sc->sc_vhid - 1); enaddr[3] = 0x40000 >> (sc->sc_vhid - 1); enaddr[4] = 0; enaddr[5] = 0; } else { enaddr[0] = 0; enaddr[1] = 0; enaddr[2] = 0x5e; enaddr[3] = 0; enaddr[4] = 1; enaddr[5] = sc->sc_vhid; } if_set_sadl(&sc->sc_if, enaddr, sizeof(enaddr), false); } void carp_addr_updated(void *v) { struct carp_softc *sc = (struct carp_softc *) v; struct ifaddr *ifa; int new_naddrs = 0, new_naddrs6 = 0; IFADDR_FOREACH(ifa, &sc->sc_if) { if (ifa->ifa_addr->sa_family == AF_INET) new_naddrs++; else if (ifa->ifa_addr->sa_family == AF_INET6) new_naddrs6++; } /* Handle a callback after SIOCDIFADDR */ if (new_naddrs < sc->sc_naddrs || new_naddrs6 < sc->sc_naddrs6) { struct in_addr mc_addr; struct in_multi *inm; sc->sc_naddrs = new_naddrs; sc->sc_naddrs6 = new_naddrs6; /* Re-establish multicast membership removed by in_control */ mc_addr.s_addr = INADDR_CARP_GROUP; IN_LOOKUP_MULTI(mc_addr, &sc->sc_if, inm); if (inm == NULL) { memset(&sc->sc_imo, 0, sizeof(sc->sc_imo)); if (sc->sc_carpdev != NULL && sc->sc_naddrs > 0) carp_join_multicast(sc); } if (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) { sc->sc_if.if_flags &= ~IFF_UP; carp_set_state(sc, INIT); } else carp_hmac_prepare(sc); } carp_setrun(sc, 0); } int carp_set_addr(struct carp_softc *sc, struct sockaddr_in *sin) { struct ifnet *ifp = sc->sc_carpdev; struct in_ifaddr *ia, *ia_if; int error = 0; if (sin->sin_addr.s_addr == 0) { if (!(sc->sc_if.if_flags & IFF_UP)) carp_set_state(sc, INIT); if (sc->sc_naddrs) sc->sc_if.if_flags |= IFF_UP; carp_setrun(sc, 0); return (0); } /* we have to do this by hand to ensure we don't match on ourselves */ ia_if = NULL; for (ia = TAILQ_FIRST(&in_ifaddrhead); ia; ia = TAILQ_NEXT(ia, ia_list)) { /* and, yeah, we need a multicast-capable iface too */ if (ia->ia_ifp != &sc->sc_if && ia->ia_ifp->if_type != IFT_CARP && (ia->ia_ifp->if_flags & IFF_MULTICAST) && (sin->sin_addr.s_addr & ia->ia_subnetmask) == ia->ia_subnet) { if (!ia_if) ia_if = ia; } } if (ia_if) { ia = ia_if; if (ifp) { if (ifp != ia->ia_ifp) return (EADDRNOTAVAIL); } else { ifp = ia->ia_ifp; } } if ((error = carp_set_ifp(sc, ifp))) return (error); if (sc->sc_carpdev == NULL) return (EADDRNOTAVAIL); if (sc->sc_naddrs == 0 && (error = carp_join_multicast(sc)) != 0) return (error); sc->sc_naddrs++; if (sc->sc_carpdev != NULL) sc->sc_if.if_flags |= IFF_UP; carp_set_state(sc, INIT); carp_setrun(sc, 0); /* * Hook if_addrhooks so that we get a callback after in_ifinit has run, * to correct any inappropriate routes that it inserted. */ if (sc->ah_cookie == 0) { /* XXX link address hook */ } return (0); } int carp_join_multicast(struct carp_softc *sc) { struct ip_moptions *imo = &sc->sc_imo, tmpimo; struct in_addr addr; memset(&tmpimo, 0, sizeof(tmpimo)); addr.s_addr = INADDR_CARP_GROUP; if ((tmpimo.imo_membership[0] = in_addmulti(&addr, &sc->sc_if)) == NULL) { return (ENOBUFS); } imo->imo_membership[0] = tmpimo.imo_membership[0]; imo->imo_num_memberships = 1; imo->imo_multicast_ifp = &sc->sc_if; imo->imo_multicast_ttl = CARP_DFLTTL; imo->imo_multicast_loop = 0; return (0); } #ifdef INET6 int carp_set_addr6(struct carp_softc *sc, struct sockaddr_in6 *sin6) { struct ifnet *ifp = sc->sc_carpdev; struct in6_ifaddr *ia, *ia_if; int error = 0; if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) { if (!(sc->sc_if.if_flags & IFF_UP)) carp_set_state(sc, INIT); if (sc->sc_naddrs6) sc->sc_if.if_flags |= IFF_UP; carp_setrun(sc, 0); return (0); } /* we have to do this by hand to ensure we don't match on ourselves */ ia_if = NULL; for (ia = in6_ifaddr; ia; ia = ia->ia_next) { 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 != &sc->sc_if && ia->ia_ifp->if_type != IFT_CARP && (ia->ia_ifp->if_flags & IFF_MULTICAST) && (i == 4)) { if (!ia_if) ia_if = ia; } } if (ia_if) { ia = ia_if; if (sc->sc_carpdev) { if (sc->sc_carpdev != ia->ia_ifp) return (EADDRNOTAVAIL); } else { ifp = ia->ia_ifp; } } if ((error = carp_set_ifp(sc, ifp))) return (error); if (sc->sc_carpdev == NULL) return (EADDRNOTAVAIL); if (sc->sc_naddrs6 == 0 && (error = carp_join_multicast6(sc)) != 0) return (error); sc->sc_naddrs6++; if (sc->sc_carpdev != NULL) sc->sc_if.if_flags |= IFF_UP; carp_set_state(sc, INIT); carp_setrun(sc, 0); return (0); } int carp_join_multicast6(struct carp_softc *sc) { struct in6_multi_mship *imm, *imm2; struct ip6_moptions *im6o = &sc->sc_im6o; struct sockaddr_in6 addr6; int error; /* Join IPv6 CARP multicast group */ memset(&addr6, 0, sizeof(addr6)); addr6.sin6_family = AF_INET6; addr6.sin6_len = sizeof(addr6); addr6.sin6_addr.s6_addr16[0] = htons(0xff02); addr6.sin6_addr.s6_addr16[1] = htons(sc->sc_if.if_index); addr6.sin6_addr.s6_addr8[15] = 0x12; if ((imm = in6_joingroup(&sc->sc_if, &addr6.sin6_addr, &error, 0)) == NULL) { return (error); } /* join solicited multicast address */ memset(&addr6.sin6_addr, 0, sizeof(addr6.sin6_addr)); addr6.sin6_addr.s6_addr16[0] = htons(0xff02); addr6.sin6_addr.s6_addr16[1] = htons(sc->sc_if.if_index); addr6.sin6_addr.s6_addr32[1] = 0; addr6.sin6_addr.s6_addr32[2] = htonl(1); addr6.sin6_addr.s6_addr32[3] = 0; addr6.sin6_addr.s6_addr8[12] = 0xff; if ((imm2 = in6_joingroup(&sc->sc_if, &addr6.sin6_addr, &error, 0)) == NULL) { in6_leavegroup(imm); return (error); } /* apply v6 multicast membership */ im6o->im6o_multicast_ifp = &sc->sc_if; if (imm) LIST_INSERT_HEAD(&im6o->im6o_memberships, imm, i6mm_chain); if (imm2) LIST_INSERT_HEAD(&im6o->im6o_memberships, imm2, i6mm_chain); return (0); } #endif /* INET6 */ int carp_ioctl(struct ifnet *ifp, u_long cmd, void *data) { struct lwp *l = curlwp; /* XXX */ struct carp_softc *sc = ifp->if_softc, *vr; struct carpreq carpr; struct ifaddr *ifa; struct ifreq *ifr; struct ifnet *cdev = NULL; int error = 0; ifa = (struct ifaddr *)data; ifr = (struct ifreq *)data; switch (cmd) { case SIOCINITIFADDR: switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: sc->sc_if.if_flags |= IFF_UP; memcpy(ifa->ifa_dstaddr, ifa->ifa_addr, sizeof(struct sockaddr)); error = carp_set_addr(sc, satosin(ifa->ifa_addr)); break; #endif /* INET */ #ifdef INET6 case AF_INET6: sc->sc_if.if_flags|= IFF_UP; error = carp_set_addr6(sc, satosin6(ifa->ifa_addr)); break; #endif /* INET6 */ default: error = EAFNOSUPPORT; break; } break; case SIOCSIFFLAGS: if ((error = ifioctl_common(ifp, cmd, data)) != 0) break; 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) { /* we need the interface up to bow out */ sc->sc_if.if_flags |= IFF_UP; sc->sc_bow_out = 1; carp_send_ad(sc); } sc->sc_if.if_flags &= ~IFF_UP; carp_set_state(sc, INIT); carp_setrun(sc, 0); } else if (sc->sc_state == INIT && (ifr->ifr_flags & IFF_UP)) { sc->sc_if.if_flags |= IFF_UP; carp_setrun(sc, 0); } break; case SIOCSVH: if (l == NULL) break; if ((error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE, KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd, NULL)) != 0) break; if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr))) break; error = 1; if (carpr.carpr_carpdev[0] != '\0' && (cdev = ifunit(carpr.carpr_carpdev)) == NULL) return (EINVAL); if ((error = carp_set_ifp(sc, cdev))) return (error); 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(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) return (EINVAL); } sc->sc_vhid = carpr.carpr_vhid; carp_set_enaddr(sc); carp_set_state(sc, INIT); error--; } if (carpr.carpr_advbase > 0 || carpr.carpr_advskew > 0) { if (carpr.carpr_advskew > 254) { error = EINVAL; break; } if (carpr.carpr_advbase > 255) { error = EINVAL; break; } sc->sc_advbase = carpr.carpr_advbase; sc->sc_advskew = carpr.carpr_advskew; error--; } memcpy(sc->sc_key, carpr.carpr_key, sizeof(sc->sc_key)); if (error > 0) error = EINVAL; else { error = 0; carp_setrun(sc, 0); } break; case SIOCGVH: memset(&carpr, 0, sizeof(carpr)); if (sc->sc_carpdev != NULL) strlcpy(carpr.carpr_carpdev, sc->sc_carpdev->if_xname, IFNAMSIZ); carpr.carpr_state = sc->sc_state; carpr.carpr_vhid = sc->sc_vhid; carpr.carpr_advbase = sc->sc_advbase; carpr.carpr_advskew = sc->sc_advskew; if ((l != NULL) && (error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE, KAUTH_REQ_NETWORK_INTERFACE_SETPRIV, ifp, (void *)cmd, NULL)) == 0) memcpy(carpr.carpr_key, sc->sc_key, sizeof(carpr.carpr_key)); error = copyout(&carpr, ifr->ifr_data, sizeof(carpr)); break; case SIOCADDMULTI: error = carp_ether_addmulti(sc, ifr); break; case SIOCDELMULTI: error = carp_ether_delmulti(sc, ifr); break; default: error = ether_ioctl(ifp, cmd, data); } carp_hmac_prepare(sc); return (error); } /* * Start output on carp interface. This function should never be called. */ 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, const struct sockaddr *sa, struct rtentry *rt) { struct carp_softc *sc = ((struct carp_softc *)ifp->if_softc); if (sc->sc_carpdev != NULL && sc->sc_state == MASTER) { return (sc->sc_carpdev->if_output(ifp, m, sa, rt)); } else { m_freem(m); return (ENETUNREACH); } } void carp_set_state(struct carp_softc *sc, int state) { static const char *carp_states[] = { CARP_STATES }; if (sc->sc_state == state) return; CARP_LOG(sc, ("state transition from: %s -> to: %s", carp_states[sc->sc_state], carp_states[state])); sc->sc_state = state; switch (state) { case BACKUP: sc->sc_if.if_link_state = LINK_STATE_DOWN; break; case MASTER: sc->sc_if.if_link_state = LINK_STATE_UP; break; default: sc->sc_if.if_link_state = LINK_STATE_UNKNOWN; break; } rt_ifmsg(&sc->sc_if); } void carp_carpdev_state(void *v) { struct carp_if *cif; struct carp_softc *sc; struct ifnet *ifp = v; if (ifp->if_type == IFT_CARP) return; cif = (struct carp_if *)ifp->if_carp; TAILQ_FOREACH(sc, &cif->vhif_vrs, sc_list) { int suppressed = sc->sc_suppress; if (sc->sc_carpdev->if_link_state == LINK_STATE_DOWN || !(sc->sc_carpdev->if_flags & IFF_UP)) { sc->sc_if.if_flags &= ~IFF_RUNNING; callout_stop(&sc->sc_ad_tmo); callout_stop(&sc->sc_md_tmo); callout_stop(&sc->sc_md6_tmo); carp_set_state(sc, INIT); sc->sc_suppress = 1; carp_setrun(sc, 0); if (!suppressed) { carp_suppress_preempt++; if (carp_suppress_preempt == 1) carp_send_ad_all(); } } else { carp_set_state(sc, INIT); sc->sc_suppress = 0; carp_setrun(sc, 0); if (suppressed) carp_suppress_preempt--; } } } int carp_ether_addmulti(struct carp_softc *sc, struct ifreq *ifr) { const struct sockaddr *sa = ifreq_getaddr(SIOCADDMULTI, ifr); struct ifnet *ifp; struct carp_mc_entry *mc; u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN]; int error; ifp = sc->sc_carpdev; if (ifp == NULL) return (EINVAL); error = ether_addmulti(sa, &sc->sc_ac); if (error != ENETRESET) return (error); /* * This is new multicast address. We have to tell parent * about it. Also, remember this multicast address so that * we can delete them on unconfigure. */ mc = malloc(sizeof(struct carp_mc_entry), M_DEVBUF, M_NOWAIT); if (mc == NULL) { error = ENOMEM; goto alloc_failed; } /* * As ether_addmulti() returns ENETRESET, following two * statement shouldn't fail. */ (void)ether_multiaddr(sa, addrlo, addrhi); ETHER_LOOKUP_MULTI(addrlo, addrhi, &sc->sc_ac, mc->mc_enm); memcpy(&mc->mc_addr, sa, sa->sa_len); LIST_INSERT_HEAD(&sc->carp_mc_listhead, mc, mc_entries); error = (*ifp->if_ioctl)(ifp, SIOCADDMULTI, ifr); if (error != 0) goto ioctl_failed; return (error); ioctl_failed: LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF); alloc_failed: (void)ether_delmulti(sa, &sc->sc_ac); return (error); } int carp_ether_delmulti(struct carp_softc *sc, struct ifreq *ifr) { const struct sockaddr *sa = ifreq_getaddr(SIOCDELMULTI, ifr); struct ifnet *ifp; struct ether_multi *enm; struct carp_mc_entry *mc; u_int8_t addrlo[ETHER_ADDR_LEN], addrhi[ETHER_ADDR_LEN]; int error; ifp = sc->sc_carpdev; if (ifp == NULL) return (EINVAL); /* * Find a key to lookup carp_mc_entry. We have to do this * before calling ether_delmulti for obvious reason. */ if ((error = ether_multiaddr(sa, addrlo, addrhi)) != 0) return (error); ETHER_LOOKUP_MULTI(addrlo, addrhi, &sc->sc_ac, enm); if (enm == NULL) return (EINVAL); LIST_FOREACH(mc, &sc->carp_mc_listhead, mc_entries) if (mc->mc_enm == enm) break; /* We won't delete entries we didn't add */ if (mc == NULL) return (EINVAL); error = ether_delmulti(sa, &sc->sc_ac); if (error != ENETRESET) return (error); /* We no longer use this multicast address. Tell parent so. */ error = (*ifp->if_ioctl)(ifp, SIOCDELMULTI, ifr); if (error == 0) { /* And forget about this address. */ LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF); } else (void)ether_addmulti(sa, &sc->sc_ac); return (error); } /* * Delete any multicast address we have asked to add from parent * interface. Called when the carp is being unconfigured. */ void carp_ether_purgemulti(struct carp_softc *sc) { struct ifnet *ifp = sc->sc_carpdev; /* Parent. */ struct carp_mc_entry *mc; union { struct ifreq ifreq; struct { char ifr_name[IFNAMSIZ]; struct sockaddr_storage ifr_ss; } ifreq_storage; } u; struct ifreq *ifr = &u.ifreq; if (ifp == NULL) return; memcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ); while ((mc = LIST_FIRST(&sc->carp_mc_listhead)) != NULL) { memcpy(&ifr->ifr_addr, &mc->mc_addr, mc->mc_addr.ss_len); (void)(*ifp->if_ioctl)(ifp, SIOCDELMULTI, ifr); LIST_REMOVE(mc, mc_entries); free(mc, M_DEVBUF); } } static int sysctl_net_inet_carp_stats(SYSCTLFN_ARGS) { return (NETSTAT_SYSCTL(carpstat_percpu, CARP_NSTATS)); } void carp_init(void) { sysctl_net_inet_carp_setup(NULL); } static void sysctl_net_inet_carp_setup(struct sysctllog **clog) { sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "net", NULL, NULL, 0, NULL, 0, CTL_NET, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "inet", NULL, NULL, 0, NULL, 0, CTL_NET, PF_INET, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_NODE, "carp", SYSCTL_DESCR("CARP related settings"), NULL, 0, NULL, 0, CTL_NET, PF_INET, IPPROTO_CARP, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "preempt", SYSCTL_DESCR("Enable CARP Preempt"), NULL, 0, &carp_opts[CARPCTL_PREEMPT], 0, CTL_NET, PF_INET, IPPROTO_CARP, CTL_CREATE, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "arpbalance", SYSCTL_DESCR("Enable ARP balancing"), NULL, 0, &carp_opts[CARPCTL_ARPBALANCE], 0, CTL_NET, PF_INET, IPPROTO_CARP, CTL_CREATE, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "allow", SYSCTL_DESCR("Enable CARP"), NULL, 0, &carp_opts[CARPCTL_ALLOW], 0, CTL_NET, PF_INET, IPPROTO_CARP, CTL_CREATE, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "log", SYSCTL_DESCR("CARP logging"), NULL, 0, &carp_opts[CARPCTL_LOG], 0, CTL_NET, PF_INET, IPPROTO_CARP, CTL_CREATE, CTL_EOL); sysctl_createv(clog, 0, NULL, NULL, CTLFLAG_PERMANENT, CTLTYPE_STRUCT, "stats", SYSCTL_DESCR("CARP statistics"), sysctl_net_inet_carp_stats, 0, NULL, 0, CTL_NET, PF_INET, IPPROTO_CARP, CARPCTL_STATS, CTL_EOL); }