/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2002 Michael Shalayeff. * Copyright (c) 2003 Ryan McBride. * Copyright (c) 2011 Gleb Smirnoff * 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("$FreeBSD$"); #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 #if defined(INET) || defined(INET6) #include #include #include #include #include #endif #ifdef INET #include #include #endif #ifdef INET6 #include #include #include #include #include #include #endif #include static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses"); struct carp_softc { struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */ struct ifaddr **sc_ifas; /* Our ifaddrs. */ struct sockaddr_dl sc_addr; /* Our link level address. */ struct callout sc_ad_tmo; /* Advertising timeout. */ #ifdef INET struct callout sc_md_tmo; /* Master down timeout. */ #endif #ifdef INET6 struct callout sc_md6_tmo; /* XXX: Master down timeout. */ #endif struct mtx sc_mtx; int sc_vhid; int sc_advskew; int sc_advbase; int sc_naddrs; int sc_naddrs6; int sc_ifasiz; enum { INIT = 0, BACKUP, MASTER } sc_state; 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_init_counter; uint64_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; TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */ LIST_ENTRY(carp_softc) sc_next; /* On the global list. */ }; struct carp_if { #ifdef INET int cif_naddrs; #endif #ifdef INET6 int cif_naddrs6; #endif TAILQ_HEAD(, carp_softc) cif_vrs; #ifdef INET struct ip_moptions cif_imo; #endif #ifdef INET6 struct ip6_moptions cif_im6o; #endif struct ifnet *cif_ifp; struct mtx cif_mtx; uint32_t cif_flags; #define CIF_PROMISC 0x00000001 }; #define CARP_INET 0 #define CARP_INET6 1 static int proto_reg[] = {-1, -1}; /* * Brief design of carp(4). * * Any carp-capable ifnet may have a list of carp softcs hanging off * its ifp->if_carp pointer. Each softc represents one unique virtual * host id, or vhid. The softc has a back pointer to the ifnet. All * softcs are joined in a global list, which has quite limited use. * * Any interface address that takes part in CARP negotiation has a * pointer to the softc of its vhid, ifa->ifa_carp. That could be either * AF_INET or AF_INET6 address. * * Although, one can get the softc's backpointer to ifnet and traverse * through its ifp->if_addrhead queue to find all interface addresses * involved in CARP, we keep a growable array of ifaddr pointers. This * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that * do calls into the network stack, thus avoiding LORs. * * Locking: * * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), * callout-driven events and ioctl()s. * * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. * To traverse the global list we use the mutex carp_mtx. * * Known issues with locking: * * - Sending ad, we put the pointer to the softc in an mtag, and no reference * counting is done on the softc. * - On module unload we may race (?) with packet processing thread * dereferencing our function pointers. */ /* Accept incoming CARP packets. */ static VNET_DEFINE(int, carp_allow) = 1; #define V_carp_allow VNET(carp_allow) /* Preempt slower nodes. */ static VNET_DEFINE(int, carp_preempt) = 0; #define V_carp_preempt VNET(carp_preempt) /* Log level. */ static VNET_DEFINE(int, carp_log) = 1; #define V_carp_log VNET(carp_log) /* Global advskew demotion. */ static VNET_DEFINE(int, carp_demotion) = 0; #define V_carp_demotion VNET(carp_demotion) /* Send error demotion factor. */ static VNET_DEFINE(int, carp_senderr_adj) = CARP_MAXSKEW; #define V_carp_senderr_adj VNET(carp_senderr_adj) /* Iface down demotion factor. */ static VNET_DEFINE(int, carp_ifdown_adj) = CARP_MAXSKEW; #define V_carp_ifdown_adj VNET(carp_ifdown_adj) static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW, 0, "CARP"); SYSCTL_INT(_net_inet_carp, OID_AUTO, allow, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(carp_allow), 0, "Accept incoming CARP packets"); SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(carp_log), 0, "CARP log level"); SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_demote_adj_sysctl, "I", "Adjust demotion factor (skew of advskew)"); SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(carp_ifdown_adj), 0, "Interface down demotion factor adjustment"); VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); VNET_PCPUSTAT_SYSINIT(carpstats); VNET_PCPUSTAT_SYSUNINIT(carpstats); #define CARPSTATS_ADD(name, val) \ counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ sizeof(uint64_t)], (val)) #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ NULL, MTX_DEF) #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ NULL, MTX_DEF) #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) #define CIF_FREE(cif) do { \ CIF_LOCK(cif); \ if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ carp_free_if(cif); \ else \ CIF_UNLOCK(cif); \ } while (0) #define CARP_LOG(...) do { \ if (V_carp_log > 0) \ log(LOG_INFO, "carp: " __VA_ARGS__); \ } while (0) #define CARP_DEBUG(...) do { \ if (V_carp_log > 1) \ log(LOG_DEBUG, __VA_ARGS__); \ } while (0) #define IFNET_FOREACH_IFA(ifp, ifa) \ IF_ADDR_LOCK_ASSERT(ifp); \ TAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ if ((ifa)->ifa_carp != NULL) #define CARP_FOREACH_IFA(sc, ifa) \ CARP_LOCK_ASSERT(sc); \ for (int _i = 0; \ _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ ((ifa) = sc->sc_ifas[_i]) != NULL; \ ++_i) #define IFNET_FOREACH_CARP(ifp, sc) \ KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) #define DEMOTE_ADVSKEW(sc) \ (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); static struct carp_softc *carp_alloc(struct ifnet *); static void carp_destroy(struct carp_softc *); static struct carp_if *carp_alloc_if(struct ifnet *); static void carp_free_if(struct carp_if *); static void carp_set_state(struct carp_softc *, int, const char* reason); static void carp_sc_state(struct carp_softc *); static void carp_setrun(struct carp_softc *, sa_family_t); static void carp_master_down(void *); static void carp_master_down_locked(struct carp_softc *, const char* reason); static void carp_send_ad(void *); static void carp_send_ad_locked(struct carp_softc *); static void carp_addroute(struct carp_softc *); static void carp_ifa_addroute(struct ifaddr *); static void carp_delroute(struct carp_softc *); static void carp_ifa_delroute(struct ifaddr *); static void carp_send_ad_all(void *, int); static void carp_demote_adj(int, char *); static LIST_HEAD(, carp_softc) carp_list; static struct mtx carp_mtx; static struct sx carp_sx; static struct task carp_sendall_task = TASK_INITIALIZER(0, carp_send_ad_all, NULL); static void carp_hmac_prepare(struct carp_softc *sc) { uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; uint8_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 CARP_LOCK_ASSERT(sc); /* 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; CARP_FOREACH_IFA(sc, ifa) { 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, 0, sizeof(cur6)); do { found = 0; last6 = cur6; memset(&cur6, 0xff, sizeof(cur6)); CARP_FOREACH_IFA(sc, ifa) { 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 (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; } static void carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], unsigned char md[20]) { SHA1_CTX sha1ctx; CARP_LOCK_ASSERT(sc); /* 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, uint32_t counter[2], unsigned char md[20]) { unsigned char md2[20]; CARP_LOCK_ASSERT(sc); carp_hmac_generate(sc, counter, md2); return (bcmp(md, md2, sizeof(md2))); } /* * process input packet. * we have rearranged checks order compared to the rfc, * but it seems more efficient this way or not possible otherwise. */ #ifdef INET int carp_input(struct mbuf **mp, int *offp, int proto) { struct mbuf *m = *mp; struct ip *ip = mtod(m, struct ip *); struct carp_header *ch; int iplen, len; iplen = *offp; *mp = NULL; CARPSTATS_INC(carps_ipackets); if (!V_carp_allow) { m_freem(m); return (IPPROTO_DONE); } /* verify that the IP TTL is 255. */ if (ip->ip_ttl != CARP_DFLTTL) { CARPSTATS_INC(carps_badttl); CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, ip->ip_ttl, m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } iplen = ip->ip_hl << 2; if (m->m_pkthdr.len < iplen + sizeof(*ch)) { CARPSTATS_INC(carps_badlen); CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " "on %s\n", __func__, m->m_len - sizeof(struct ip), m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } if (iplen + sizeof(*ch) < m->m_len) { if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { CARPSTATS_INC(carps_hdrops); CARP_DEBUG("%s: pullup failed\n", __func__); return (IPPROTO_DONE); } 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_DEBUG("%s: packet too short %d on %s\n", __func__, m->m_pkthdr.len, m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } if ((m = m_pullup(m, len)) == NULL) { CARPSTATS_INC(carps_hdrops); return (IPPROTO_DONE); } ip = mtod(m, struct ip *); ch = (struct carp_header *)((char *)ip + iplen); /* verify the CARP checksum */ m->m_data += iplen; if (in_cksum(m, len - iplen)) { CARPSTATS_INC(carps_badsum); CARP_DEBUG("%s: checksum failed on %s\n", __func__, m->m_pkthdr.rcvif->if_xname); m_freem(m); return (IPPROTO_DONE); } m->m_data -= iplen; carp_input_c(m, ch, AF_INET); return (IPPROTO_DONE); } #endif #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 (!V_carp_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_DEBUG("%s: packet received on non-carp interface: %s\n", __func__, 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_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 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_DEBUG("%s: packet size %u too small\n", __func__, len); return (IPPROTO_DONE); } /* verify the CARP checksum */ m->m_data += *offp; if (in_cksum(m, sizeof(*ch))) { CARPSTATS_INC(carps_badsum); CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 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 */ /* * This routine should not be necessary at all, but some switches * (VMWare ESX vswitches) can echo our own packets back at us, * and we must ignore them or they will cause us to drop out of * MASTER mode. * * We cannot catch all cases of network loops. Instead, what we * do here is catch any packet that arrives with a carp header * with a VHID of 0, that comes from an address that is our own. * These packets are by definition "from us" (even if they are from * a misconfigured host that is pretending to be us). * * The VHID test is outside this mini-function. */ static int carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) { #ifdef INET struct ip *ip4; struct in_addr in4; #endif #ifdef INET6 struct ip6_hdr *ip6; struct in6_addr in6; #endif switch (af) { #ifdef INET case AF_INET: ip4 = mtod(m, struct ip *); in4 = ifatoia(ifa)->ia_addr.sin_addr; return (in4.s_addr == ip4->ip_src.s_addr); #endif #ifdef INET6 case AF_INET6: ip6 = mtod(m, struct ip6_hdr *); in6 = ifatoia6(ifa)->ia_addr.sin6_addr; return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); #endif default: break; } return (0); } static void carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) { struct ifnet *ifp = m->m_pkthdr.rcvif; struct ifaddr *ifa, *match; struct carp_softc *sc; uint64_t tmp_counter; struct timeval sc_tv, ch_tv; int error; /* * Verify that the VHID is valid on the receiving interface. * * There should be just one match. If there are none * the VHID is not valid and we drop the packet. If * there are multiple VHID matches, take just the first * one, for compatibility with previous code. While we're * scanning, check for obvious loops in the network topology * (these should never happen, and as noted above, we may * miss real loops; this is just a double-check). */ IF_ADDR_RLOCK(ifp); error = 0; match = NULL; IFNET_FOREACH_IFA(ifp, ifa) { if (match == NULL && ifa->ifa_carp != NULL && ifa->ifa_addr->sa_family == af && ifa->ifa_carp->sc_vhid == ch->carp_vhid) match = ifa; if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) error = ELOOP; } ifa = error ? NULL : match; if (ifa != NULL) ifa_ref(ifa); IF_ADDR_RUNLOCK(ifp); if (ifa == NULL) { if (error == ELOOP) { CARP_DEBUG("dropping looped packet on interface %s\n", ifp->if_xname); CARPSTATS_INC(carps_badif); /* ??? */ } else { CARPSTATS_INC(carps_badvhid); } m_freem(m); return; } /* verify the CARP version. */ if (ch->carp_version != CARP_VERSION) { CARPSTATS_INC(carps_badver); CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, ch->carp_version); ifa_free(ifa); m_freem(m); return; } sc = ifa->ifa_carp; CARP_LOCK(sc); ifa_free(ifa); if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { CARPSTATS_INC(carps_badauth); CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, sc->sc_vhid, ifp->if_xname); goto out; } 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; sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 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_set_state(sc, BACKUP, "more frequent advertisement received"); carp_setrun(sc, 0); carp_delroute(sc); } 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 (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { carp_master_down_locked(sc, "preempting a slower master"); 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_master_down_locked(sc, "master will time out"); break; } /* * Otherwise, we reset the counter and wait for the next * advertisement. */ carp_setrun(sc, af); break; } out: CARP_UNLOCK(sc); m_freem(m); } static int carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) { struct m_tag *mtag; 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 */ if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), M_NOWAIT)) == NULL) { m_freem(m); CARPSTATS_INC(carps_onomem); return (ENOMEM); } bcopy(&sc, mtag + 1, sizeof(sc)); m_tag_prepend(m, mtag); return (0); } /* * To avoid LORs and possible recursions this function shouldn't * be called directly, but scheduled via taskqueue. */ static void carp_send_ad_all(void *ctx __unused, int pending __unused) { struct carp_softc *sc; mtx_lock(&carp_mtx); LIST_FOREACH(sc, &carp_list, sc_next) if (sc->sc_state == MASTER) { CARP_LOCK(sc); CURVNET_SET(sc->sc_carpdev->if_vnet); carp_send_ad_locked(sc); CURVNET_RESTORE(); CARP_UNLOCK(sc); } mtx_unlock(&carp_mtx); } /* Send a periodic advertisement, executed in callout context. */ static void carp_send_ad(void *v) { struct carp_softc *sc = v; CARP_LOCK_ASSERT(sc); CURVNET_SET(sc->sc_carpdev->if_vnet); carp_send_ad_locked(sc); CURVNET_RESTORE(); CARP_UNLOCK(sc); } static void carp_send_ad_error(struct carp_softc *sc, int error) { if (error) { if (sc->sc_sendad_errors < INT_MAX) sc->sc_sendad_errors++; if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { static const char fmt[] = "send error %d on %s"; char msg[sizeof(fmt) + IFNAMSIZ]; sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); carp_demote_adj(V_carp_senderr_adj, msg); } sc->sc_sendad_success = 0; } else { if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { static const char fmt[] = "send ok on %s"; char msg[sizeof(fmt) + IFNAMSIZ]; sprintf(msg, fmt, sc->sc_carpdev->if_xname); carp_demote_adj(-V_carp_senderr_adj, msg); sc->sc_sendad_errors = 0; } else sc->sc_sendad_errors = 0; } } /* * Pick the best ifaddr on the given ifp for sending CARP * advertisements. * * "Best" here is defined by ifa_preferred(). This function is much * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). * * (This could be simplified to return the actual address, except that * it has a different format in AF_INET and AF_INET6.) */ static struct ifaddr * carp_best_ifa(int af, struct ifnet *ifp) { struct ifaddr *ifa, *best; if (af >= AF_MAX) return (NULL); best = NULL; IF_ADDR_RLOCK(ifp); TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family == af && (best == NULL || ifa_preferred(best, ifa))) best = ifa; } IF_ADDR_RUNLOCK(ifp); if (best != NULL) ifa_ref(best); return (best); } static void carp_send_ad_locked(struct carp_softc *sc) { struct carp_header ch; struct timeval tv; struct ifaddr *ifa; struct carp_header *ch_ptr; struct mbuf *m; int len, advskew; CARP_LOCK_ASSERT(sc); advskew = DEMOTE_ADVSKEW(sc); tv.tv_sec = sc->sc_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 = sc->sc_advbase; ch.carp_advskew = advskew; ch.carp_authlen = 7; /* XXX DEFINE */ ch.carp_pad1 = 0; /* must be zero */ ch.carp_cksum = 0; /* XXXGL: OpenBSD picks first ifaddr with needed family. */ #ifdef INET if (sc->sc_naddrs) { struct ip *ip; m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { CARPSTATS_INC(carps_onomem); goto resched; } len = sizeof(*ip) + sizeof(ch); m->m_pkthdr.len = len; m->m_pkthdr.rcvif = NULL; m->m_len = len; M_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_off = htons(IP_DF); ip->ip_ttl = CARP_DFLTTL; ip->ip_p = IPPROTO_CARP; ip->ip_sum = 0; ip_fillid(ip); ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); if (ifa != NULL) { ip->ip_src.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; ifa_free(ifa); } else ip->ip_src.s_addr = 0; 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)) goto resched; m->m_data += sizeof(*ip); ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); m->m_data -= sizeof(*ip); CARPSTATS_INC(carps_opackets); carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, &sc->sc_carpdev->if_carp->cif_imo, NULL)); } #endif /* INET */ #ifdef INET6 if (sc->sc_naddrs6) { struct ip6_hdr *ip6; m = m_gethdr(M_NOWAIT, MT_DATA); if (m == NULL) { CARPSTATS_INC(carps_onomem); goto resched; } len = sizeof(*ip6) + sizeof(ch); m->m_pkthdr.len = len; m->m_pkthdr.rcvif = NULL; m->m_len = len; M_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; /* set the source address */ ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); if (ifa != NULL) { bcopy(IFA_IN6(ifa), &ip6->ip6_src, sizeof(struct in6_addr)); ifa_free(ifa); } else /* This should never happen with IPv6. */ bzero(&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) { m_freem(m); CARP_DEBUG("%s: in6_setscope failed\n", __func__); goto resched; } ch_ptr = (struct carp_header *)(&ip6[1]); bcopy(&ch, ch_ptr, sizeof(ch)); if (carp_prepare_ad(m, sc, ch_ptr)) goto resched; m->m_data += sizeof(*ip6); ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); m->m_data -= sizeof(*ip6); CARPSTATS_INC(carps_opackets6); carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); } #endif /* INET6 */ resched: callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); } static void carp_addroute(struct carp_softc *sc) { struct ifaddr *ifa; CARP_FOREACH_IFA(sc, ifa) carp_ifa_addroute(ifa); } static void carp_ifa_addroute(struct ifaddr *ifa) { switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: in_addprefix(ifatoia(ifa), RTF_UP); ifa_add_loopback_route(ifa, (struct sockaddr *)&ifatoia(ifa)->ia_addr); break; #endif #ifdef INET6 case AF_INET6: ifa_add_loopback_route(ifa, (struct sockaddr *)&ifatoia6(ifa)->ia_addr); nd6_add_ifa_lle(ifatoia6(ifa)); break; #endif } } static void carp_delroute(struct carp_softc *sc) { struct ifaddr *ifa; CARP_FOREACH_IFA(sc, ifa) carp_ifa_delroute(ifa); } static void carp_ifa_delroute(struct ifaddr *ifa) { switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: ifa_del_loopback_route(ifa, (struct sockaddr *)&ifatoia(ifa)->ia_addr); in_scrubprefix(ifatoia(ifa), LLE_STATIC); break; #endif #ifdef INET6 case AF_INET6: ifa_del_loopback_route(ifa, (struct sockaddr *)&ifatoia6(ifa)->ia_addr); nd6_rem_ifa_lle(ifatoia6(ifa), 1); break; #endif } } int carp_master(struct ifaddr *ifa) { struct carp_softc *sc = ifa->ifa_carp; return (sc->sc_state == MASTER); } #ifdef INET /* * 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; struct in_addr addr; CARP_FOREACH_IFA(sc, ifa) { if (ifa->ifa_addr->sa_family != AF_INET) continue; addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); } } int carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) { struct carp_softc *sc = ifa->ifa_carp; if (sc->sc_state == MASTER) { *enaddr = LLADDR(&sc->sc_addr); return (1); } return (0); } #endif #ifdef INET6 static void carp_send_na(struct carp_softc *sc) { static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; struct ifaddr *ifa; struct in6_addr *in6; CARP_FOREACH_IFA(sc, ifa) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; in6 = IFA_IN6(ifa); nd6_na_output(sc->sc_carpdev, &mcast, in6, ND_NA_FLAG_OVERRIDE, 1, NULL); DELAY(1000); /* XXX */ } } /* * Returns ifa in case it's a carp address and it is MASTER, or if the address * matches and is not a carp address. Returns NULL otherwise. */ struct ifaddr * carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) { struct ifaddr *ifa; ifa = NULL; IF_ADDR_RLOCK(ifp); TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) continue; if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) ifa = NULL; else ifa_ref(ifa); break; } IF_ADDR_RUNLOCK(ifp); return (ifa); } caddr_t carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) { struct ifaddr *ifa; IF_ADDR_RLOCK(ifp); IFNET_FOREACH_IFA(ifp, ifa) if (ifa->ifa_addr->sa_family == AF_INET6 && IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { struct carp_softc *sc = ifa->ifa_carp; struct m_tag *mtag; IF_ADDR_RUNLOCK(ifp); mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), M_NOWAIT); if (mtag == NULL) /* Better a bit than nothing. */ return (LLADDR(&sc->sc_addr)); bcopy(&sc, mtag + 1, sizeof(sc)); m_tag_prepend(m, mtag); return (LLADDR(&sc->sc_addr)); } IF_ADDR_RUNLOCK(ifp); return (NULL); } #endif /* INET6 */ int carp_forus(struct ifnet *ifp, u_char *dhost) { struct carp_softc *sc; uint8_t *ena = dhost; if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) return (0); CIF_LOCK(ifp->if_carp); IFNET_FOREACH_CARP(ifp, sc) { CARP_LOCK(sc); if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), ETHER_ADDR_LEN)) { CARP_UNLOCK(sc); CIF_UNLOCK(ifp->if_carp); return (1); } CARP_UNLOCK(sc); } CIF_UNLOCK(ifp->if_carp); return (0); } /* Master down timeout event, executed in callout context. */ static void carp_master_down(void *v) { struct carp_softc *sc = v; CARP_LOCK_ASSERT(sc); CURVNET_SET(sc->sc_carpdev->if_vnet); if (sc->sc_state == BACKUP) { carp_master_down_locked(sc, "master timed out"); } CURVNET_RESTORE(); CARP_UNLOCK(sc); } static void carp_master_down_locked(struct carp_softc *sc, const char *reason) { CARP_LOCK_ASSERT(sc); switch (sc->sc_state) { case BACKUP: carp_set_state(sc, MASTER, reason); carp_send_ad_locked(sc); #ifdef INET carp_send_arp(sc); #endif #ifdef INET6 carp_send_na(sc); #endif carp_setrun(sc, 0); carp_addroute(sc); break; case INIT: case MASTER: #ifdef INVARIANTS panic("carp: VHID %u@%s: master_down event in %s state\n", sc->sc_vhid, sc->sc_carpdev->if_xname, sc->sc_state ? "MASTER" : "INIT"); #endif 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; CARP_LOCK_ASSERT(sc); if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || sc->sc_carpdev->if_link_state != LINK_STATE_UP || (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0)) return; switch (sc->sc_state) { case INIT: carp_set_state(sc, BACKUP, "initialization complete"); 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 #ifdef INET6 case AF_INET6: callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), carp_master_down, sc); break; #endif default: #ifdef INET if (sc->sc_naddrs) callout_reset(&sc->sc_md_tmo, tvtohz(&tv), carp_master_down, sc); #endif #ifdef INET6 if (sc->sc_naddrs6) callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), carp_master_down, sc); #endif 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; } } /* * Setup multicast structures. */ static int carp_multicast_setup(struct carp_if *cif, sa_family_t sa) { struct ifnet *ifp = cif->cif_ifp; int error = 0; switch (sa) { #ifdef INET case AF_INET: { struct ip_moptions *imo = &cif->cif_imo; struct in_addr addr; if (imo->imo_membership) return (0); imo->imo_membership = (struct in_multi **)malloc( (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, M_WAITOK); imo->imo_mfilters = NULL; imo->imo_max_memberships = IP_MIN_MEMBERSHIPS; imo->imo_multicast_vif = -1; addr.s_addr = htonl(INADDR_CARP_GROUP); if ((error = in_joingroup(ifp, &addr, NULL, &imo->imo_membership[0])) != 0) { free(imo->imo_membership, M_CARP); break; } imo->imo_num_memberships++; imo->imo_multicast_ifp = ifp; imo->imo_multicast_ttl = CARP_DFLTTL; imo->imo_multicast_loop = 0; break; } #endif #ifdef INET6 case AF_INET6: { struct ip6_moptions *im6o = &cif->cif_im6o; struct in6_addr in6; struct in6_multi *in6m; if (im6o->im6o_membership) return (0); im6o->im6o_membership = (struct in6_multi **)malloc( (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, M_ZERO | M_WAITOK); im6o->im6o_mfilters = NULL; im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; im6o->im6o_multicast_hlim = CARP_DFLTTL; im6o->im6o_multicast_ifp = ifp; /* Join IPv6 CARP multicast group. */ bzero(&in6, sizeof(in6)); in6.s6_addr16[0] = htons(0xff02); in6.s6_addr8[15] = 0x12; if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { free(im6o->im6o_membership, M_CARP); break; } in6m = NULL; if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { free(im6o->im6o_membership, M_CARP); break; } 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] = 0; in6.s6_addr8[12] = 0xff; if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { in6_mc_leave(im6o->im6o_membership[0], NULL); free(im6o->im6o_membership, M_CARP); break; } in6m = NULL; if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { in6_mc_leave(im6o->im6o_membership[0], NULL); free(im6o->im6o_membership, M_CARP); break; } im6o->im6o_membership[1] = in6m; im6o->im6o_num_memberships++; break; } #endif } return (error); } /* * Free multicast structures. */ static void carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) { sx_assert(&carp_sx, SA_XLOCKED); switch (sa) { #ifdef INET case AF_INET: if (cif->cif_naddrs == 0) { struct ip_moptions *imo = &cif->cif_imo; in_leavegroup(imo->imo_membership[0], NULL); KASSERT(imo->imo_mfilters == NULL, ("%s: imo_mfilters != NULL", __func__)); free(imo->imo_membership, M_CARP); imo->imo_membership = NULL; } break; #endif #ifdef INET6 case AF_INET6: if (cif->cif_naddrs6 == 0) { struct ip6_moptions *im6o = &cif->cif_im6o; in6_mc_leave(im6o->im6o_membership[0], NULL); in6_mc_leave(im6o->im6o_membership[1], NULL); KASSERT(im6o->im6o_mfilters == NULL, ("%s: im6o_mfilters != NULL", __func__)); free(im6o->im6o_membership, M_CARP); im6o->im6o_membership = NULL; } break; #endif } } int carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) { struct m_tag *mtag; struct carp_softc *sc; if (!sa) return (0); switch (sa->sa_family) { #ifdef INET case AF_INET: break; #endif #ifdef INET6 case AF_INET6: break; #endif default: return (0); } mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); if (mtag == NULL) return (0); bcopy(mtag + 1, &sc, sizeof(sc)); /* Set the source MAC address to the Virtual Router MAC Address. */ switch (ifp->if_type) { case IFT_ETHER: case IFT_BRIDGE: 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; default: printf("%s: carp is not supported for the %d interface type\n", ifp->if_xname, ifp->if_type); return (EOPNOTSUPP); } return (0); } static struct carp_softc* carp_alloc(struct ifnet *ifp) { struct carp_softc *sc; struct carp_if *cif; sx_assert(&carp_sx, SA_XLOCKED); if ((cif = ifp->if_carp) == NULL) cif = carp_alloc_if(ifp); sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); sc->sc_advbase = CARP_DFLTINTV; sc->sc_vhid = -1; /* required setting */ sc->sc_init_counter = 1; sc->sc_state = INIT; sc->sc_ifasiz = sizeof(struct ifaddr *); sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); sc->sc_carpdev = ifp; CARP_LOCK_INIT(sc); #ifdef INET callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); #endif #ifdef INET6 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); #endif callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); CIF_LOCK(cif); TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); CIF_UNLOCK(cif); mtx_lock(&carp_mtx); LIST_INSERT_HEAD(&carp_list, sc, sc_next); mtx_unlock(&carp_mtx); return (sc); } static void carp_grow_ifas(struct carp_softc *sc) { struct ifaddr **new; new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); CARP_LOCK(sc); bcopy(sc->sc_ifas, new, sc->sc_ifasiz); free(sc->sc_ifas, M_CARP); sc->sc_ifas = new; sc->sc_ifasiz *= 2; CARP_UNLOCK(sc); } static void carp_destroy(struct carp_softc *sc) { struct ifnet *ifp = sc->sc_carpdev; struct carp_if *cif = ifp->if_carp; sx_assert(&carp_sx, SA_XLOCKED); if (sc->sc_suppress) carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); CARP_UNLOCK(sc); CIF_LOCK(cif); TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); CIF_UNLOCK(cif); mtx_lock(&carp_mtx); LIST_REMOVE(sc, sc_next); mtx_unlock(&carp_mtx); callout_drain(&sc->sc_ad_tmo); #ifdef INET callout_drain(&sc->sc_md_tmo); #endif #ifdef INET6 callout_drain(&sc->sc_md6_tmo); #endif CARP_LOCK_DESTROY(sc); free(sc->sc_ifas, M_CARP); free(sc, M_CARP); } static struct carp_if* carp_alloc_if(struct ifnet *ifp) { struct carp_if *cif; int error; cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); if ((error = ifpromisc(ifp, 1)) != 0) printf("%s: ifpromisc(%s) failed: %d\n", __func__, ifp->if_xname, error); else cif->cif_flags |= CIF_PROMISC; CIF_LOCK_INIT(cif); cif->cif_ifp = ifp; TAILQ_INIT(&cif->cif_vrs); IF_ADDR_WLOCK(ifp); ifp->if_carp = cif; if_ref(ifp); IF_ADDR_WUNLOCK(ifp); return (cif); } static void carp_free_if(struct carp_if *cif) { struct ifnet *ifp = cif->cif_ifp; CIF_LOCK_ASSERT(cif); KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", __func__)); IF_ADDR_WLOCK(ifp); ifp->if_carp = NULL; IF_ADDR_WUNLOCK(ifp); CIF_LOCK_DESTROY(cif); if (cif->cif_flags & CIF_PROMISC) ifpromisc(ifp, 0); if_rele(ifp); free(cif, M_CARP); } static void carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) { CARP_LOCK(sc); 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 (priv) bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); else bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); CARP_UNLOCK(sc); } int carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) { struct carpreq carpr; struct ifnet *ifp; struct carp_softc *sc = NULL; int error = 0, locked = 0; if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) return (error); ifp = ifunit_ref(ifr->ifr_name); if (ifp == NULL) return (ENXIO); switch (ifp->if_type) { case IFT_ETHER: case IFT_L2VLAN: case IFT_BRIDGE: case IFT_FDDI: break; default: error = EOPNOTSUPP; goto out; } if ((ifp->if_flags & IFF_MULTICAST) == 0) { error = EADDRNOTAVAIL; goto out; } sx_xlock(&carp_sx); switch (cmd) { case SIOCSVH: if ((error = priv_check(td, PRIV_NETINET_CARP))) break; if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { error = EINVAL; break; } if (ifp->if_carp) { IFNET_FOREACH_CARP(ifp, sc) if (sc->sc_vhid == carpr.carpr_vhid) break; } if (sc == NULL) { sc = carp_alloc(ifp); CARP_LOCK(sc); sc->sc_vhid = carpr.carpr_vhid; LLADDR(&sc->sc_addr)[0] = 0; LLADDR(&sc->sc_addr)[1] = 0; LLADDR(&sc->sc_addr)[2] = 0x5e; LLADDR(&sc->sc_addr)[3] = 0; LLADDR(&sc->sc_addr)[4] = 1; LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; } else CARP_LOCK(sc); locked = 1; if (carpr.carpr_advbase > 0) { if (carpr.carpr_advbase > 255 || carpr.carpr_advbase < CARP_DFLTINTV) { error = EINVAL; break; } sc->sc_advbase = carpr.carpr_advbase; } if (carpr.carpr_advskew >= 255) { error = EINVAL; break; } sc->sc_advskew = carpr.carpr_advskew; if (carpr.carpr_key[0] != '\0') { bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); carp_hmac_prepare(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, "user requested via ifconfig"); carp_setrun(sc, 0); carp_delroute(sc); break; case MASTER: carp_master_down_locked(sc, "user requested via ifconfig"); break; default: break; } } break; case SIOCGVH: { int priveleged; if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { error = EINVAL; break; } if (carpr.carpr_count < 1) { error = EMSGSIZE; break; } if (ifp->if_carp == NULL) { error = ENOENT; break; } priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); if (carpr.carpr_vhid != 0) { IFNET_FOREACH_CARP(ifp, sc) if (sc->sc_vhid == carpr.carpr_vhid) break; if (sc == NULL) { error = ENOENT; break; } carp_carprcp(&carpr, sc, priveleged); error = copyout(&carpr, ifr_data_get_ptr(ifr), sizeof(carpr)); } else { int i, count; count = 0; IFNET_FOREACH_CARP(ifp, sc) count++; if (count > carpr.carpr_count) { CIF_UNLOCK(ifp->if_carp); error = EMSGSIZE; break; } i = 0; IFNET_FOREACH_CARP(ifp, sc) { carp_carprcp(&carpr, sc, priveleged); carpr.carpr_count = count; error = copyout(&carpr, (caddr_t)ifr_data_get_ptr(ifr) + (i * sizeof(carpr)), sizeof(carpr)); if (error) { CIF_UNLOCK(ifp->if_carp); break; } i++; } } break; } default: error = EINVAL; } sx_xunlock(&carp_sx); out: if (locked) CARP_UNLOCK(sc); if_rele(ifp); return (error); } static int carp_get_vhid(struct ifaddr *ifa) { if (ifa == NULL || ifa->ifa_carp == NULL) return (0); return (ifa->ifa_carp->sc_vhid); } int carp_attach(struct ifaddr *ifa, int vhid) { struct ifnet *ifp = ifa->ifa_ifp; struct carp_if *cif = ifp->if_carp; struct carp_softc *sc; int index, error; KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: #endif #ifdef INET6 case AF_INET6: #endif break; default: return (EPROTOTYPE); } sx_xlock(&carp_sx); if (ifp->if_carp == NULL) { sx_xunlock(&carp_sx); return (ENOPROTOOPT); } IFNET_FOREACH_CARP(ifp, sc) if (sc->sc_vhid == vhid) break; if (sc == NULL) { sx_xunlock(&carp_sx); return (ENOENT); } error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); if (error) { CIF_FREE(cif); sx_xunlock(&carp_sx); return (error); } index = sc->sc_naddrs + sc->sc_naddrs6 + 1; if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) carp_grow_ifas(sc); switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: cif->cif_naddrs++; sc->sc_naddrs++; break; #endif #ifdef INET6 case AF_INET6: cif->cif_naddrs6++; sc->sc_naddrs6++; break; #endif } ifa_ref(ifa); CARP_LOCK(sc); sc->sc_ifas[index - 1] = ifa; ifa->ifa_carp = sc; carp_hmac_prepare(sc); carp_sc_state(sc); CARP_UNLOCK(sc); sx_xunlock(&carp_sx); return (0); } void carp_detach(struct ifaddr *ifa, bool keep_cif) { struct ifnet *ifp = ifa->ifa_ifp; struct carp_if *cif = ifp->if_carp; struct carp_softc *sc = ifa->ifa_carp; int i, index; KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); sx_xlock(&carp_sx); CARP_LOCK(sc); /* Shift array. */ index = sc->sc_naddrs + sc->sc_naddrs6; for (i = 0; i < index; i++) if (sc->sc_ifas[i] == ifa) break; KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); for (; i < index - 1; i++) sc->sc_ifas[i] = sc->sc_ifas[i+1]; sc->sc_ifas[index - 1] = NULL; switch (ifa->ifa_addr->sa_family) { #ifdef INET case AF_INET: cif->cif_naddrs--; sc->sc_naddrs--; break; #endif #ifdef INET6 case AF_INET6: cif->cif_naddrs6--; sc->sc_naddrs6--; break; #endif } carp_ifa_delroute(ifa); carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); ifa->ifa_carp = NULL; ifa_free(ifa); carp_hmac_prepare(sc); carp_sc_state(sc); if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) carp_destroy(sc); else CARP_UNLOCK(sc); if (!keep_cif) CIF_FREE(cif); sx_xunlock(&carp_sx); } static void carp_set_state(struct carp_softc *sc, int state, const char *reason) { CARP_LOCK_ASSERT(sc); if (sc->sc_state != state) { const char *carp_states[] = { CARP_STATES }; char subsys[IFNAMSIZ+5]; snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, sc->sc_carpdev->if_xname); CARP_LOG("%s: %s -> %s (%s)\n", subsys, carp_states[sc->sc_state], carp_states[state], reason); sc->sc_state = state; devctl_notify("CARP", subsys, carp_states[state], NULL); } } static void carp_linkstate(struct ifnet *ifp) { struct carp_softc *sc; CIF_LOCK(ifp->if_carp); IFNET_FOREACH_CARP(ifp, sc) { CARP_LOCK(sc); carp_sc_state(sc); CARP_UNLOCK(sc); } CIF_UNLOCK(ifp->if_carp); } static void carp_sc_state(struct carp_softc *sc) { CARP_LOCK_ASSERT(sc); if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || !(sc->sc_carpdev->if_flags & IFF_UP)) { callout_stop(&sc->sc_ad_tmo); #ifdef INET callout_stop(&sc->sc_md_tmo); #endif #ifdef INET6 callout_stop(&sc->sc_md6_tmo); #endif carp_set_state(sc, INIT, "hardware interface down"); carp_setrun(sc, 0); if (!sc->sc_suppress) carp_demote_adj(V_carp_ifdown_adj, "interface down"); sc->sc_suppress = 1; } else { carp_set_state(sc, INIT, "hardware interface up"); carp_setrun(sc, 0); if (sc->sc_suppress) carp_demote_adj(-V_carp_ifdown_adj, "interface up"); sc->sc_suppress = 0; } } static void carp_demote_adj(int adj, char *reason) { atomic_add_int(&V_carp_demotion, adj); CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); } static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) { int new, error; new = V_carp_demotion; error = sysctl_handle_int(oidp, &new, 0, req); if (error || !req->newptr) return (error); carp_demote_adj(new, "sysctl"); return (0); } #ifdef INET extern struct domain inetdomain; static struct protosw in_carp_protosw = { .pr_type = SOCK_RAW, .pr_domain = &inetdomain, .pr_protocol = IPPROTO_CARP, .pr_flags = PR_ATOMIC|PR_ADDR, .pr_input = carp_input, .pr_output = rip_output, .pr_ctloutput = rip_ctloutput, .pr_usrreqs = &rip_usrreqs }; #endif #ifdef INET6 extern struct domain inet6domain; static struct protosw in6_carp_protosw = { .pr_type = SOCK_RAW, .pr_domain = &inet6domain, .pr_protocol = IPPROTO_CARP, .pr_flags = PR_ATOMIC|PR_ADDR, .pr_input = carp6_input, .pr_output = rip6_output, .pr_ctloutput = rip6_ctloutput, .pr_usrreqs = &rip6_usrreqs }; #endif static void carp_mod_cleanup(void) { #ifdef INET if (proto_reg[CARP_INET] == 0) { (void)ipproto_unregister(IPPROTO_CARP); pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); proto_reg[CARP_INET] = -1; } carp_iamatch_p = NULL; #endif #ifdef INET6 if (proto_reg[CARP_INET6] == 0) { (void)ip6proto_unregister(IPPROTO_CARP); pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); proto_reg[CARP_INET6] = -1; } carp_iamatch6_p = NULL; carp_macmatch6_p = NULL; #endif carp_ioctl_p = NULL; carp_attach_p = NULL; carp_detach_p = NULL; carp_get_vhid_p = NULL; carp_linkstate_p = NULL; carp_forus_p = NULL; carp_output_p = NULL; carp_demote_adj_p = NULL; carp_master_p = NULL; mtx_unlock(&carp_mtx); taskqueue_drain(taskqueue_swi, &carp_sendall_task); mtx_destroy(&carp_mtx); sx_destroy(&carp_sx); } static int carp_mod_load(void) { int err; mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); sx_init(&carp_sx, "carp_sx"); LIST_INIT(&carp_list); carp_get_vhid_p = carp_get_vhid; carp_forus_p = carp_forus; carp_output_p = carp_output; carp_linkstate_p = carp_linkstate; carp_ioctl_p = carp_ioctl; carp_attach_p = carp_attach; carp_detach_p = carp_detach; carp_demote_adj_p = carp_demote_adj; carp_master_p = carp_master; #ifdef INET6 carp_iamatch6_p = carp_iamatch6; carp_macmatch6_p = carp_macmatch6; proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, (struct protosw *)&in6_carp_protosw); if (proto_reg[CARP_INET6]) { printf("carp: error %d attaching to PF_INET6\n", proto_reg[CARP_INET6]); carp_mod_cleanup(); return (proto_reg[CARP_INET6]); } err = ip6proto_register(IPPROTO_CARP); if (err) { printf("carp: error %d registering with INET6\n", err); carp_mod_cleanup(); return (err); } #endif #ifdef INET carp_iamatch_p = carp_iamatch; proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); if (proto_reg[CARP_INET]) { printf("carp: error %d attaching to PF_INET\n", proto_reg[CARP_INET]); carp_mod_cleanup(); return (proto_reg[CARP_INET]); } err = ipproto_register(IPPROTO_CARP); if (err) { printf("carp: error %d registering with INET\n", err); carp_mod_cleanup(); return (err); } #endif return (0); } static int carp_modevent(module_t mod, int type, void *data) { switch (type) { case MOD_LOAD: return carp_mod_load(); /* NOTREACHED */ case MOD_UNLOAD: mtx_lock(&carp_mtx); if (LIST_EMPTY(&carp_list)) carp_mod_cleanup(); else { mtx_unlock(&carp_mtx); return (EBUSY); } break; default: return (EINVAL); } return (0); } static moduledata_t carp_mod = { "carp", carp_modevent, 0 }; DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);