diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c index e09ad3d47382..ef50ec9ca964 100644 --- a/sys/netinet/if_ether.c +++ b/sys/netinet/if_ether.c @@ -1,1519 +1,1523 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. 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. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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 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. * * @(#)if_ether.c 8.1 (Berkeley) 6/10/93 */ /* * Ethernet address resolution protocol. * TODO: * add "inuse/lock" bit (or ref. count) along with valid bit */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.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 #ifdef INET #include #endif #include #define SIN(s) ((const struct sockaddr_in *)(s)) static struct timeval arp_lastlog; static int arp_curpps; static int arp_maxpps = 1; /* Simple ARP state machine */ enum arp_llinfo_state { ARP_LLINFO_INCOMPLETE = 0, /* No LLE data */ ARP_LLINFO_REACHABLE, /* LLE is valid */ ARP_LLINFO_VERIFY, /* LLE is valid, need refresh */ ARP_LLINFO_DELETED, /* LLE is deleted */ }; SYSCTL_DECL(_net_link_ether); static SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); static SYSCTL_NODE(_net_link_ether, PF_ARP, arp, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); /* timer values */ VNET_DEFINE_STATIC(int, arpt_keep) = (20*60); /* once resolved, good for 20 * minutes */ VNET_DEFINE_STATIC(int, arp_maxtries) = 5; VNET_DEFINE_STATIC(int, arp_proxyall) = 0; VNET_DEFINE_STATIC(int, arpt_down) = 20; /* keep incomplete entries for * 20 seconds */ VNET_DEFINE_STATIC(int, arpt_rexmit) = 1; /* retransmit arp entries, sec*/ VNET_PCPUSTAT_DEFINE(struct arpstat, arpstat); /* ARP statistics, see if_arp.h */ VNET_PCPUSTAT_SYSINIT(arpstat); #ifdef VIMAGE VNET_PCPUSTAT_SYSUNINIT(arpstat); #endif /* VIMAGE */ VNET_DEFINE_STATIC(int, arp_maxhold) = 16; #define V_arpt_keep VNET(arpt_keep) #define V_arpt_down VNET(arpt_down) #define V_arpt_rexmit VNET(arpt_rexmit) #define V_arp_maxtries VNET(arp_maxtries) #define V_arp_proxyall VNET(arp_proxyall) #define V_arp_maxhold VNET(arp_maxhold) SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_age, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arpt_keep), 0, "ARP entry lifetime in seconds"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_maxtries), 0, "ARP resolution attempts before returning error"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_proxyall), 0, "Enable proxy ARP for all suitable requests"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, wait, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arpt_down), 0, "Incomplete ARP entry lifetime in seconds"); SYSCTL_VNET_PCPUSTAT(_net_link_ether_arp, OID_AUTO, stats, struct arpstat, arpstat, "ARP statistics (struct arpstat, net/if_arp.h)"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxhold, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_maxhold), 0, "Number of packets to hold per ARP entry"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, max_log_per_second, CTLFLAG_RW, &arp_maxpps, 0, "Maximum number of remotely triggered ARP messages that can be " "logged per second"); /* * Due to the exponential backoff algorithm used for the interval between GARP * retransmissions, the maximum number of retransmissions is limited for * sanity. This limit corresponds to a maximum interval between retransmissions * of 2^16 seconds ~= 18 hours. * * Making this limit more dynamic is more complicated than worthwhile, * especially since sending out GARPs spaced days apart would be of little * use. A maximum dynamic limit would look something like: * * const int max = fls(INT_MAX / hz) - 1; */ #define MAX_GARP_RETRANSMITS 16 static int sysctl_garp_rexmit(SYSCTL_HANDLER_ARGS); static int garp_rexmit_count = 0; /* GARP retransmission setting. */ SYSCTL_PROC(_net_link_ether_inet, OID_AUTO, garp_rexmit_count, CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_MPSAFE, &garp_rexmit_count, 0, sysctl_garp_rexmit, "I", "Number of times to retransmit GARP packets;" " 0 to disable, maximum of 16"); VNET_DEFINE_STATIC(int, arp_log_level) = LOG_INFO; /* Min. log(9) level. */ #define V_arp_log_level VNET(arp_log_level) SYSCTL_INT(_net_link_ether_arp, OID_AUTO, log_level, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(arp_log_level), 0, "Minimum log(9) level for recording rate limited arp log messages. " "The higher will be log more (emerg=0, info=6 (default), debug=7)."); #define ARP_LOG(pri, ...) do { \ if ((pri) <= V_arp_log_level && \ ppsratecheck(&arp_lastlog, &arp_curpps, arp_maxpps)) \ log((pri), "arp: " __VA_ARGS__); \ } while (0) static void arpintr(struct mbuf *); static void arptimer(void *); #ifdef INET static void in_arpinput(struct mbuf *); #endif static void arp_check_update_lle(struct arphdr *ah, struct in_addr isaddr, struct ifnet *ifp, int bridged, struct llentry *la); static void arp_mark_lle_reachable(struct llentry *la); static void arp_iflladdr(void *arg __unused, struct ifnet *ifp); static eventhandler_tag iflladdr_tag; static const struct netisr_handler arp_nh = { .nh_name = "arp", .nh_handler = arpintr, .nh_proto = NETISR_ARP, .nh_policy = NETISR_POLICY_SOURCE, }; /* * Timeout routine. Age arp_tab entries periodically. */ static void arptimer(void *arg) { struct llentry *lle = (struct llentry *)arg; struct ifnet *ifp; int r_skip_req; if (lle->la_flags & LLE_STATIC) { return; } LLE_WLOCK(lle); if (callout_pending(&lle->lle_timer)) { /* * Here we are a bit odd here in the treatment of * active/pending. If the pending bit is set, it got * rescheduled before I ran. The active * bit we ignore, since if it was stopped * in ll_tablefree() and was currently running * it would have return 0 so the code would * not have deleted it since the callout could * not be stopped so we want to go through * with the delete here now. If the callout * was restarted, the pending bit will be back on and * we just want to bail since the callout_reset would * return 1 and our reference would have been removed * by arpresolve() below. */ LLE_WUNLOCK(lle); return; } ifp = lle->lle_tbl->llt_ifp; CURVNET_SET(ifp->if_vnet); switch (lle->ln_state) { case ARP_LLINFO_REACHABLE: /* * Expiration time is approaching. * Let's try to refresh entry if it is still * in use. * * Set r_skip_req to get feedback from * fast path. Change state and re-schedule * ourselves. */ LLE_REQ_LOCK(lle); lle->r_skip_req = 1; LLE_REQ_UNLOCK(lle); lle->ln_state = ARP_LLINFO_VERIFY; callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); CURVNET_RESTORE(); return; case ARP_LLINFO_VERIFY: LLE_REQ_LOCK(lle); r_skip_req = lle->r_skip_req; LLE_REQ_UNLOCK(lle); if (r_skip_req == 0 && lle->la_preempt > 0) { /* Entry was used, issue refresh request */ struct epoch_tracker et; struct in_addr dst; dst = lle->r_l3addr.addr4; lle->la_preempt--; callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); NET_EPOCH_ENTER(et); arprequest(ifp, NULL, &dst, NULL); NET_EPOCH_EXIT(et); CURVNET_RESTORE(); return; } /* Nothing happened. Reschedule if not too late */ if (lle->la_expire > time_uptime) { callout_schedule(&lle->lle_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); CURVNET_RESTORE(); return; } break; case ARP_LLINFO_INCOMPLETE: case ARP_LLINFO_DELETED: break; } if ((lle->la_flags & LLE_DELETED) == 0) { int evt; if (lle->la_flags & LLE_VALID) evt = LLENTRY_EXPIRED; else evt = LLENTRY_TIMEDOUT; EVENTHANDLER_INVOKE(lle_event, lle, evt); } callout_stop(&lle->lle_timer); /* XXX: LOR avoidance. We still have ref on lle. */ LLE_WUNLOCK(lle); IF_AFDATA_LOCK(ifp); LLE_WLOCK(lle); /* Guard against race with other llentry_free(). */ if (lle->la_flags & LLE_LINKED) { LLE_REMREF(lle); lltable_unlink_entry(lle->lle_tbl, lle); } IF_AFDATA_UNLOCK(ifp); size_t pkts_dropped = llentry_free(lle); ARPSTAT_ADD(dropped, pkts_dropped); ARPSTAT_INC(timeouts); CURVNET_RESTORE(); } /* * Stores link-layer header for @ifp in format suitable for if_output() * into buffer @buf. Resulting header length is stored in @bufsize. * * Returns 0 on success. */ static int arp_fillheader(struct ifnet *ifp, struct arphdr *ah, int bcast, u_char *buf, size_t *bufsize) { struct if_encap_req ereq; int error; bzero(buf, *bufsize); bzero(&ereq, sizeof(ereq)); ereq.buf = buf; ereq.bufsize = *bufsize; ereq.rtype = IFENCAP_LL; ereq.family = AF_ARP; ereq.lladdr = ar_tha(ah); ereq.hdata = (u_char *)ah; if (bcast) ereq.flags = IFENCAP_FLAG_BROADCAST; error = ifp->if_requestencap(ifp, &ereq); if (error == 0) *bufsize = ereq.bufsize; return (error); } /* * Broadcast an ARP request. Caller specifies: * - arp header source ip address * - arp header target ip address * - arp header source ethernet address */ static int arprequest_internal(struct ifnet *ifp, const struct in_addr *sip, const struct in_addr *tip, u_char *enaddr) { struct mbuf *m; struct arphdr *ah; struct sockaddr sa; u_char *carpaddr = NULL; uint8_t linkhdr[LLE_MAX_LINKHDR]; size_t linkhdrsize; struct route ro; int error; NET_EPOCH_ASSERT(); if (sip == NULL) { /* * The caller did not supply a source address, try to find * a compatible one among those assigned to this interface. */ struct ifaddr *ifa; CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET) continue; if (ifa->ifa_carp) { if ((*carp_iamatch_p)(ifa, &carpaddr) == 0) continue; sip = &IA_SIN(ifa)->sin_addr; } else { carpaddr = NULL; sip = &IA_SIN(ifa)->sin_addr; } if (0 == ((sip->s_addr ^ tip->s_addr) & IA_MASKSIN(ifa)->sin_addr.s_addr)) break; /* found it. */ } if (sip == NULL) { printf("%s: cannot find matching address\n", __func__); return (EADDRNOTAVAIL); } } if (enaddr == NULL) enaddr = carpaddr ? carpaddr : (u_char *)IF_LLADDR(ifp); if ((m = m_gethdr(M_NOWAIT, MT_DATA)) == NULL) return (ENOMEM); m->m_len = sizeof(*ah) + 2 * sizeof(struct in_addr) + 2 * ifp->if_addrlen; m->m_pkthdr.len = m->m_len; M_ALIGN(m, m->m_len); ah = mtod(m, struct arphdr *); bzero((caddr_t)ah, m->m_len); #ifdef MAC mac_netinet_arp_send(ifp, m); #endif ah->ar_pro = htons(ETHERTYPE_IP); ah->ar_hln = ifp->if_addrlen; /* hardware address length */ ah->ar_pln = sizeof(struct in_addr); /* protocol address length */ ah->ar_op = htons(ARPOP_REQUEST); bcopy(enaddr, ar_sha(ah), ah->ar_hln); bcopy(sip, ar_spa(ah), ah->ar_pln); bcopy(tip, ar_tpa(ah), ah->ar_pln); sa.sa_family = AF_ARP; sa.sa_len = 2; /* Calculate link header for sending frame */ bzero(&ro, sizeof(ro)); linkhdrsize = sizeof(linkhdr); error = arp_fillheader(ifp, ah, 1, linkhdr, &linkhdrsize); if (error != 0 && error != EAFNOSUPPORT) { ARP_LOG(LOG_ERR, "Failed to calculate ARP header on %s: %d\n", if_name(ifp), error); return (error); } ro.ro_prepend = linkhdr; ro.ro_plen = linkhdrsize; ro.ro_flags = 0; m->m_flags |= M_BCAST; m_clrprotoflags(m); /* Avoid confusing lower layers. */ error = (*ifp->if_output)(ifp, m, &sa, &ro); ARPSTAT_INC(txrequests); if (error) { ARPSTAT_INC(txerrors); ARP_LOG(LOG_DEBUG, "Failed to send ARP packet on %s: %d\n", if_name(ifp), error); } return (error); } void arprequest(struct ifnet *ifp, const struct in_addr *sip, const struct in_addr *tip, u_char *enaddr) { (void) arprequest_internal(ifp, sip, tip, enaddr); } /* * Resolve an IP address into an ethernet address - heavy version. * Used internally by arpresolve(). * We have already checked that we can't use an existing lle without * modification so we have to acquire an LLE_EXCLUSIVE lle lock. * * On success, desten and pflags are filled in and the function returns 0; * If the packet must be held pending resolution, we return EWOULDBLOCK * On other errors, we return the corresponding error code. * Note that m_freem() handles NULL. */ static int arpresolve_full(struct ifnet *ifp, int is_gw, int flags, struct mbuf *m, const struct sockaddr *dst, u_char *desten, uint32_t *pflags, struct llentry **plle) { struct llentry *la = NULL, *la_tmp; struct mbuf *curr = NULL; struct mbuf *next = NULL; int error, renew; char *lladdr; int ll_len; NET_EPOCH_ASSERT(); if (pflags != NULL) *pflags = 0; if (plle != NULL) *plle = NULL; if ((flags & LLE_CREATE) == 0) la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); if (la == NULL && (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) == 0) { la = lltable_alloc_entry(LLTABLE(ifp), 0, dst); if (la == NULL) { char addrbuf[INET_ADDRSTRLEN]; log(LOG_DEBUG, "arpresolve: can't allocate llinfo for %s on %s\n", inet_ntoa_r(SIN(dst)->sin_addr, addrbuf), if_name(ifp)); m_freem(m); return (EINVAL); } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(la); la_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); /* Prefer ANY existing lle over newly-created one */ if (la_tmp == NULL) lltable_link_entry(LLTABLE(ifp), la); IF_AFDATA_WUNLOCK(ifp); if (la_tmp != NULL) { lltable_free_entry(LLTABLE(ifp), la); la = la_tmp; } } if (la == NULL) { m_freem(m); return (EINVAL); } if ((la->la_flags & LLE_VALID) && ((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) { if (flags & LLE_ADDRONLY) { lladdr = la->ll_addr; ll_len = ifp->if_addrlen; } else { lladdr = la->r_linkdata; ll_len = la->r_hdrlen; } bcopy(lladdr, desten, ll_len); /* Notify LLE code that the entry was used by datapath */ llentry_mark_used(la); if (pflags != NULL) *pflags = la->la_flags & (LLE_VALID|LLE_IFADDR); if (plle) { LLE_ADDREF(la); *plle = la; } LLE_WUNLOCK(la); return (0); } renew = (la->la_asked == 0 || la->la_expire != time_uptime); /* * There is an arptab entry, but no ethernet address * response yet. Add the mbuf to the list, dropping * the oldest packet if we have exceeded the system * setting. */ if (m != NULL) { if (la->la_numheld >= V_arp_maxhold) { if (la->la_hold != NULL) { next = la->la_hold->m_nextpkt; m_freem(la->la_hold); la->la_hold = next; la->la_numheld--; ARPSTAT_INC(dropped); } } if (la->la_hold != NULL) { curr = la->la_hold; while (curr->m_nextpkt != NULL) curr = curr->m_nextpkt; curr->m_nextpkt = m; } else la->la_hold = m; la->la_numheld++; } /* * Return EWOULDBLOCK if we have tried less than arp_maxtries. It * will be masked by ether_output(). Return EHOSTDOWN/EHOSTUNREACH * if we have already sent arp_maxtries ARP requests. Retransmit the * ARP request, but not faster than one request per second. */ if (la->la_asked < V_arp_maxtries) error = EWOULDBLOCK; /* First request. */ else error = is_gw != 0 ? EHOSTUNREACH : EHOSTDOWN; if (renew) { int canceled, e; LLE_ADDREF(la); la->la_expire = time_uptime; canceled = callout_reset(&la->lle_timer, hz * V_arpt_down, arptimer, la); if (canceled) LLE_REMREF(la); la->la_asked++; LLE_WUNLOCK(la); e = arprequest_internal(ifp, NULL, &SIN(dst)->sin_addr, NULL); /* * Only overwrite 'error' in case of error; in case of success * the proper return value was already set above. */ if (e != 0) return (e); return (error); } LLE_WUNLOCK(la); return (error); } /* * Lookups link header based on an IP address. * On input: * ifp is the interface we use * is_gw != 0 if @dst represents gateway to some destination * m is the mbuf. May be NULL if we don't have a packet. * dst is the next hop, * desten is the storage to put LL header. * flags returns subset of lle flags: LLE_VALID | LLE_IFADDR * * On success, full/partial link header and flags are filled in and * the function returns 0. * If the packet must be held pending resolution, we return EWOULDBLOCK * On other errors, we return the corresponding error code. * Note that m_freem() handles NULL. */ int arpresolve(struct ifnet *ifp, int is_gw, struct mbuf *m, const struct sockaddr *dst, u_char *desten, uint32_t *pflags, struct llentry **plle) { struct llentry *la = NULL; NET_EPOCH_ASSERT(); if (pflags != NULL) *pflags = 0; if (plle != NULL) *plle = NULL; if (m != NULL) { if (m->m_flags & M_BCAST) { /* broadcast */ (void)memcpy(desten, ifp->if_broadcastaddr, ifp->if_addrlen); return (0); } if (m->m_flags & M_MCAST) { /* multicast */ ETHER_MAP_IP_MULTICAST(&SIN(dst)->sin_addr, desten); return (0); } } la = lla_lookup(LLTABLE(ifp), plle ? LLE_EXCLUSIVE : LLE_UNLOCKED, dst); if (la != NULL && (la->r_flags & RLLE_VALID) != 0) { /* Entry found, let's copy lle info */ bcopy(la->r_linkdata, desten, la->r_hdrlen); if (pflags != NULL) *pflags = LLE_VALID | (la->r_flags & RLLE_IFADDR); /* Notify the LLE handling code that the entry was used. */ llentry_mark_used(la); if (plle) { LLE_ADDREF(la); *plle = la; LLE_WUNLOCK(la); } return (0); } if (plle && la) LLE_WUNLOCK(la); return (arpresolve_full(ifp, is_gw, la == NULL ? LLE_CREATE : 0, m, dst, desten, pflags, plle)); } /* * Common length and type checks are done here, * then the protocol-specific routine is called. */ static void arpintr(struct mbuf *m) { struct arphdr *ar; struct ifnet *ifp; char *layer; int hlen; ifp = m->m_pkthdr.rcvif; if (m->m_len < sizeof(struct arphdr) && ((m = m_pullup(m, sizeof(struct arphdr))) == NULL)) { ARP_LOG(LOG_NOTICE, "packet with short header received on %s\n", if_name(ifp)); return; } ar = mtod(m, struct arphdr *); /* Check if length is sufficient */ if (m->m_len < arphdr_len(ar)) { m = m_pullup(m, arphdr_len(ar)); if (m == NULL) { ARP_LOG(LOG_NOTICE, "short packet received on %s\n", if_name(ifp)); return; } ar = mtod(m, struct arphdr *); } hlen = 0; layer = ""; switch (ntohs(ar->ar_hrd)) { case ARPHRD_ETHER: hlen = ETHER_ADDR_LEN; /* RFC 826 */ layer = "ethernet"; break; case ARPHRD_INFINIBAND: hlen = 20; /* RFC 4391, INFINIBAND_ALEN */ layer = "infiniband"; break; case ARPHRD_IEEE1394: hlen = 0; /* SHALL be 16 */ /* RFC 2734 */ layer = "firewire"; /* * Restrict too long hardware addresses. * Currently we are capable of handling 20-byte * addresses ( sizeof(lle->ll_addr) ) */ if (ar->ar_hln >= 20) hlen = 16; break; default: ARP_LOG(LOG_NOTICE, "packet with unknown hardware format 0x%02d received on " "%s\n", ntohs(ar->ar_hrd), if_name(ifp)); m_freem(m); return; } if (hlen != 0 && hlen != ar->ar_hln) { ARP_LOG(LOG_NOTICE, "packet with invalid %s address length %d received on %s\n", layer, ar->ar_hln, if_name(ifp)); m_freem(m); return; } ARPSTAT_INC(received); switch (ntohs(ar->ar_pro)) { #ifdef INET case ETHERTYPE_IP: in_arpinput(m); return; #endif } m_freem(m); } #ifdef INET /* * ARP for Internet protocols on 10 Mb/s Ethernet. * Algorithm is that given in RFC 826. * In addition, a sanity check is performed on the sender * protocol address, to catch impersonators. * We no longer handle negotiations for use of trailer protocol: * Formerly, ARP replied for protocol type ETHERTYPE_TRAIL sent * along with IP replies if we wanted trailers sent to us, * and also sent them in response to IP replies. * This allowed either end to announce the desire to receive * trailer packets. * We no longer reply to requests for ETHERTYPE_TRAIL protocol either, * but formerly didn't normally send requests. */ static int log_arp_wrong_iface = 1; static int log_arp_movements = 1; static int log_arp_permanent_modify = 1; static int allow_multicast = 0; SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_wrong_iface, CTLFLAG_RW, &log_arp_wrong_iface, 0, "log arp packets arriving on the wrong interface"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_movements, CTLFLAG_RW, &log_arp_movements, 0, "log arp replies from MACs different than the one in the cache"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_permanent_modify, CTLFLAG_RW, &log_arp_permanent_modify, 0, "log arp replies from MACs different than the one in the permanent arp entry"); SYSCTL_INT(_net_link_ether_inet, OID_AUTO, allow_multicast, CTLFLAG_RW, &allow_multicast, 0, "accept multicast addresses"); static void in_arpinput(struct mbuf *m) { struct rm_priotracker in_ifa_tracker; struct arphdr *ah; struct ifnet *ifp = m->m_pkthdr.rcvif; struct llentry *la = NULL, *la_tmp; struct ifaddr *ifa; struct in_ifaddr *ia; struct sockaddr sa; struct in_addr isaddr, itaddr, myaddr; u_int8_t *enaddr = NULL; int op; int bridged = 0, is_bridge = 0; int carped; struct sockaddr_in sin; struct sockaddr *dst; struct nhop_object *nh; uint8_t linkhdr[LLE_MAX_LINKHDR]; struct route ro; size_t linkhdrsize; int lladdr_off; int error; char addrbuf[INET_ADDRSTRLEN]; NET_EPOCH_ASSERT(); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr.s_addr = 0; if (ifp->if_bridge) bridged = 1; if (ifp->if_type == IFT_BRIDGE) is_bridge = 1; /* * We already have checked that mbuf contains enough contiguous data * to hold entire arp message according to the arp header. */ ah = mtod(m, struct arphdr *); /* * ARP is only for IPv4 so we can reject packets with * a protocol length not equal to an IPv4 address. */ if (ah->ar_pln != sizeof(struct in_addr)) { ARP_LOG(LOG_NOTICE, "requested protocol length != %zu\n", sizeof(struct in_addr)); goto drop; } if (allow_multicast == 0 && ETHER_IS_MULTICAST(ar_sha(ah))) { ARP_LOG(LOG_NOTICE, "%*D is multicast\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":"); goto drop; } op = ntohs(ah->ar_op); (void)memcpy(&isaddr, ar_spa(ah), sizeof (isaddr)); (void)memcpy(&itaddr, ar_tpa(ah), sizeof (itaddr)); if (op == ARPOP_REPLY) ARPSTAT_INC(rxreplies); /* * For a bridge, we want to check the address irrespective * of the receive interface. (This will change slightly * when we have clusters of interfaces). */ IN_IFADDR_RLOCK(&in_ifa_tracker); LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) { if (((bridged && ia->ia_ifp->if_bridge == ifp->if_bridge) || ia->ia_ifp == ifp) && itaddr.s_addr == ia->ia_addr.sin_addr.s_addr && (ia->ia_ifa.ifa_carp == NULL || (*carp_iamatch_p)(&ia->ia_ifa, &enaddr))) { ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } } LIST_FOREACH(ia, INADDR_HASH(isaddr.s_addr), ia_hash) if (((bridged && ia->ia_ifp->if_bridge == ifp->if_bridge) || ia->ia_ifp == ifp) && isaddr.s_addr == ia->ia_addr.sin_addr.s_addr) { ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } #define BDG_MEMBER_MATCHES_ARP(addr, ifp, ia) \ (ia->ia_ifp->if_bridge == ifp->if_softc && \ !bcmp(IF_LLADDR(ia->ia_ifp), IF_LLADDR(ifp), ifp->if_addrlen) && \ addr == ia->ia_addr.sin_addr.s_addr) /* * Check the case when bridge shares its MAC address with * some of its children, so packets are claimed by bridge * itself (bridge_input() does it first), but they are really * meant to be destined to the bridge member. */ if (is_bridge) { LIST_FOREACH(ia, INADDR_HASH(itaddr.s_addr), ia_hash) { if (BDG_MEMBER_MATCHES_ARP(itaddr.s_addr, ifp, ia)) { ifa_ref(&ia->ia_ifa); ifp = ia->ia_ifp; IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto match; } } } #undef BDG_MEMBER_MATCHES_ARP IN_IFADDR_RUNLOCK(&in_ifa_tracker); /* * No match, use the first inet address on the receive interface * as a dummy address for the rest of the function. */ CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) if (ifa->ifa_addr->sa_family == AF_INET && (ifa->ifa_carp == NULL || (*carp_iamatch_p)(ifa, &enaddr))) { ia = ifatoia(ifa); ifa_ref(ifa); goto match; } /* * If bridging, fall back to using any inet address. */ IN_IFADDR_RLOCK(&in_ifa_tracker); if (!bridged || (ia = CK_STAILQ_FIRST(&V_in_ifaddrhead)) == NULL) { IN_IFADDR_RUNLOCK(&in_ifa_tracker); goto drop; } ifa_ref(&ia->ia_ifa); IN_IFADDR_RUNLOCK(&in_ifa_tracker); match: if (!enaddr) enaddr = (u_int8_t *)IF_LLADDR(ifp); carped = (ia->ia_ifa.ifa_carp != NULL); myaddr = ia->ia_addr.sin_addr; ifa_free(&ia->ia_ifa); if (!bcmp(ar_sha(ah), enaddr, ifp->if_addrlen)) goto drop; /* it's from me, ignore it. */ if (!bcmp(ar_sha(ah), ifp->if_broadcastaddr, ifp->if_addrlen)) { ARP_LOG(LOG_NOTICE, "link address is broadcast for IP address " "%s!\n", inet_ntoa_r(isaddr, addrbuf)); goto drop; } if (ifp->if_addrlen != ah->ar_hln) { ARP_LOG(LOG_WARNING, "from %*D: addr len: new %d, " "i/f %d (ignored)\n", ifp->if_addrlen, (u_char *) ar_sha(ah), ":", ah->ar_hln, ifp->if_addrlen); goto drop; } /* * Warn if another host is using the same IP address, but only if the * IP address isn't 0.0.0.0, which is used for DHCP only, in which * case we suppress the warning to avoid false positive complaints of * potential misconfiguration. */ if (!bridged && !carped && isaddr.s_addr == myaddr.s_addr && myaddr.s_addr != 0) { ARP_LOG(LOG_ERR, "%*D is using my IP address %s on %s!\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", inet_ntoa_r(isaddr, addrbuf), ifp->if_xname); itaddr = myaddr; ARPSTAT_INC(dupips); goto reply; } if (ifp->if_flags & IFF_STATICARP) goto reply; bzero(&sin, sizeof(sin)); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr = isaddr; dst = (struct sockaddr *)&sin; la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); if (la != NULL) arp_check_update_lle(ah, isaddr, ifp, bridged, la); else if (itaddr.s_addr == myaddr.s_addr) { /* * Request/reply to our address, but no lle exists yet. * Calculate full link prepend to use in lle. */ linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET, ar_sha(ah), linkhdr, &linkhdrsize, &lladdr_off) != 0) goto reply; /* Allocate new entry */ la = lltable_alloc_entry(LLTABLE(ifp), 0, dst); if (la == NULL) { /* * lle creation may fail if source address belongs * to non-directly connected subnet. However, we * will try to answer the request instead of dropping * frame. */ goto reply; } lltable_set_entry_addr(ifp, la, linkhdr, linkhdrsize, lladdr_off); IF_AFDATA_WLOCK(ifp); LLE_WLOCK(la); la_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); /* * Check if lle still does not exists. * If it does, that means that we either * 1) have configured it explicitly, via * 1a) 'arp -s' static entry or * 1b) interface address static record * or * 2) it was the result of sending first packet to-host * or * 3) it was another arp reply packet we handled in * different thread. * * In all cases except 3) we definitely need to prefer * existing lle. For the sake of simplicity, prefer any * existing lle over newly-create one. */ if (la_tmp == NULL) lltable_link_entry(LLTABLE(ifp), la); IF_AFDATA_WUNLOCK(ifp); if (la_tmp == NULL) { arp_mark_lle_reachable(la); LLE_WUNLOCK(la); } else { /* Free newly-create entry and handle packet */ lltable_free_entry(LLTABLE(ifp), la); la = la_tmp; la_tmp = NULL; arp_check_update_lle(ah, isaddr, ifp, bridged, la); /* arp_check_update_lle() returns @la unlocked */ } la = NULL; } reply: if (op != ARPOP_REQUEST) goto drop; ARPSTAT_INC(rxrequests); if (itaddr.s_addr == myaddr.s_addr) { /* Shortcut.. the receiving interface is the target. */ (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), enaddr, ah->ar_hln); } else { /* * Destination address is not ours. Check if * proxyarp entry exists or proxyarp is turned on globally. */ struct llentry *lle; sin.sin_addr = itaddr; lle = lla_lookup(LLTABLE(ifp), 0, (struct sockaddr *)&sin); if ((lle != NULL) && (lle->la_flags & LLE_PUB)) { (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), lle->ll_addr, ah->ar_hln); LLE_RUNLOCK(lle); } else { if (lle != NULL) LLE_RUNLOCK(lle); if (!V_arp_proxyall) goto drop; NET_EPOCH_ASSERT(); nh = fib4_lookup(ifp->if_fib, itaddr, 0, 0, 0); if (nh == NULL) goto drop; /* * Don't send proxies for nodes on the same interface * as this one came out of, or we'll get into a fight * over who claims what Ether address. */ if (nh->nh_ifp == ifp) goto drop; (void)memcpy(ar_tha(ah), ar_sha(ah), ah->ar_hln); (void)memcpy(ar_sha(ah), enaddr, ah->ar_hln); /* * Also check that the node which sent the ARP packet * is on the interface we expect it to be on. This * avoids ARP chaos if an interface is connected to the * wrong network. */ nh = fib4_lookup(ifp->if_fib, isaddr, 0, 0, 0); if (nh == NULL) goto drop; if (nh->nh_ifp != ifp) { ARP_LOG(LOG_INFO, "proxy: ignoring request" " from %s via %s\n", inet_ntoa_r(isaddr, addrbuf), ifp->if_xname); goto drop; } #ifdef DEBUG_PROXY printf("arp: proxying for %s\n", inet_ntoa_r(itaddr, addrbuf)); #endif } } if (itaddr.s_addr == myaddr.s_addr && IN_LINKLOCAL(ntohl(itaddr.s_addr))) { /* RFC 3927 link-local IPv4; always reply by broadcast. */ #ifdef DEBUG_LINKLOCAL printf("arp: sending reply for link-local addr %s\n", inet_ntoa_r(itaddr, addrbuf)); #endif m->m_flags |= M_BCAST; m->m_flags &= ~M_MCAST; } else { /* default behaviour; never reply by broadcast. */ m->m_flags &= ~(M_BCAST|M_MCAST); } (void)memcpy(ar_tpa(ah), ar_spa(ah), ah->ar_pln); (void)memcpy(ar_spa(ah), &itaddr, ah->ar_pln); ah->ar_op = htons(ARPOP_REPLY); ah->ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */ m->m_len = sizeof(*ah) + (2 * ah->ar_pln) + (2 * ah->ar_hln); m->m_pkthdr.len = m->m_len; m->m_pkthdr.rcvif = NULL; sa.sa_family = AF_ARP; sa.sa_len = 2; /* Calculate link header for sending frame */ bzero(&ro, sizeof(ro)); linkhdrsize = sizeof(linkhdr); error = arp_fillheader(ifp, ah, 0, linkhdr, &linkhdrsize); /* * arp_fillheader() may fail due to lack of support inside encap request * routing. This is not necessary an error, AF_ARP can/should be handled * by if_output(). */ if (error != 0 && error != EAFNOSUPPORT) { ARP_LOG(LOG_ERR, "Failed to calculate ARP header on %s: %d\n", if_name(ifp), error); return; } ro.ro_prepend = linkhdr; ro.ro_plen = linkhdrsize; ro.ro_flags = 0; m_clrprotoflags(m); /* Avoid confusing lower layers. */ (*ifp->if_output)(ifp, m, &sa, &ro); ARPSTAT_INC(txreplies); return; drop: m_freem(m); } #endif /* * Checks received arp data against existing @la. * Updates lle state/performs notification if necessary. */ static void arp_check_update_lle(struct arphdr *ah, struct in_addr isaddr, struct ifnet *ifp, int bridged, struct llentry *la) { struct sockaddr sa; struct mbuf *m_hold, *m_hold_next; uint8_t linkhdr[LLE_MAX_LINKHDR]; size_t linkhdrsize; int lladdr_off; char addrbuf[INET_ADDRSTRLEN]; LLE_WLOCK_ASSERT(la); /* the following is not an error when doing bridging */ if (!bridged && la->lle_tbl->llt_ifp != ifp) { if (log_arp_wrong_iface) ARP_LOG(LOG_WARNING, "%s is on %s " "but got reply from %*D on %s\n", inet_ntoa_r(isaddr, addrbuf), la->lle_tbl->llt_ifp->if_xname, ifp->if_addrlen, (u_char *)ar_sha(ah), ":", ifp->if_xname); LLE_WUNLOCK(la); return; } if ((la->la_flags & LLE_VALID) && bcmp(ar_sha(ah), la->ll_addr, ifp->if_addrlen)) { if (la->la_flags & LLE_STATIC) { LLE_WUNLOCK(la); if (log_arp_permanent_modify) ARP_LOG(LOG_ERR, "%*D attempts to modify " "permanent entry for %s on %s\n", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", inet_ntoa_r(isaddr, addrbuf), ifp->if_xname); return; } if (log_arp_movements) { ARP_LOG(LOG_INFO, "%s moved from %*D " "to %*D on %s\n", inet_ntoa_r(isaddr, addrbuf), ifp->if_addrlen, (u_char *)la->ll_addr, ":", ifp->if_addrlen, (u_char *)ar_sha(ah), ":", ifp->if_xname); } } /* Calculate full link prepend to use in lle */ linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET, ar_sha(ah), linkhdr, &linkhdrsize, &lladdr_off) != 0) return; /* Check if something has changed */ if (memcmp(la->r_linkdata, linkhdr, linkhdrsize) != 0 || (la->la_flags & LLE_VALID) == 0) { /* Try to perform LLE update */ if (lltable_try_set_entry_addr(ifp, la, linkhdr, linkhdrsize, lladdr_off) == 0) return; /* Clear fast path feedback request if set */ la->r_skip_req = 0; } arp_mark_lle_reachable(la); /* * The packets are all freed within the call to the output * routine. * * NB: The lock MUST be released before the call to the * output routine. */ if (la->la_hold != NULL) { m_hold = la->la_hold; la->la_hold = NULL; la->la_numheld = 0; lltable_fill_sa_entry(la, &sa); LLE_WUNLOCK(la); for (; m_hold != NULL; m_hold = m_hold_next) { m_hold_next = m_hold->m_nextpkt; m_hold->m_nextpkt = NULL; /* Avoid confusing lower layers. */ m_clrprotoflags(m_hold); (*ifp->if_output)(ifp, m_hold, &sa, NULL); } } else LLE_WUNLOCK(la); } static void arp_mark_lle_reachable(struct llentry *la) { int canceled, wtime; LLE_WLOCK_ASSERT(la); la->ln_state = ARP_LLINFO_REACHABLE; EVENTHANDLER_INVOKE(lle_event, la, LLENTRY_RESOLVED); if (!(la->la_flags & LLE_STATIC)) { LLE_ADDREF(la); la->la_expire = time_uptime + V_arpt_keep; wtime = V_arpt_keep - V_arp_maxtries * V_arpt_rexmit; if (wtime < 0) wtime = V_arpt_keep; canceled = callout_reset(&la->lle_timer, hz * wtime, arptimer, la); if (canceled) LLE_REMREF(la); } la->la_asked = 0; la->la_preempt = V_arp_maxtries; } /* * Add permanent link-layer record for given interface address. */ static __noinline void arp_add_ifa_lle(struct ifnet *ifp, const struct sockaddr *dst) { struct llentry *lle, *lle_tmp; /* * Interface address LLE record is considered static * because kernel code relies on LLE_STATIC flag to check * if these entries can be rewriten by arp updates. */ lle = lltable_alloc_entry(LLTABLE(ifp), LLE_IFADDR | LLE_STATIC, dst); if (lle == NULL) { log(LOG_INFO, "arp_ifinit: cannot create arp " "entry for interface address\n"); return; } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(lle); /* Unlink any entry if exists */ lle_tmp = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst); if (lle_tmp != NULL) lltable_unlink_entry(LLTABLE(ifp), lle_tmp); lltable_link_entry(LLTABLE(ifp), lle); IF_AFDATA_WUNLOCK(ifp); if (lle_tmp != NULL) EVENTHANDLER_INVOKE(lle_event, lle_tmp, LLENTRY_EXPIRED); EVENTHANDLER_INVOKE(lle_event, lle, LLENTRY_RESOLVED); LLE_WUNLOCK(lle); if (lle_tmp != NULL) lltable_free_entry(LLTABLE(ifp), lle_tmp); } /* * Handle the garp_rexmit_count. Like sysctl_handle_int(), but limits the range * of valid values. */ static int sysctl_garp_rexmit(SYSCTL_HANDLER_ARGS) { int error; int rexmit_count = *(int *)arg1; error = sysctl_handle_int(oidp, &rexmit_count, 0, req); /* Enforce limits on any new value that may have been set. */ if (!error && req->newptr) { /* A new value was set. */ if (rexmit_count < 0) { rexmit_count = 0; } else if (rexmit_count > MAX_GARP_RETRANSMITS) { rexmit_count = MAX_GARP_RETRANSMITS; } *(int *)arg1 = rexmit_count; } return (error); } /* * Retransmit a Gratuitous ARP (GARP) and, if necessary, schedule a callout to * retransmit it again. A pending callout owns a reference to the ifa. */ static void garp_rexmit(void *arg) { struct in_ifaddr *ia = arg; if (callout_pending(&ia->ia_garp_timer) || !callout_active(&ia->ia_garp_timer)) { IF_ADDR_WUNLOCK(ia->ia_ifa.ifa_ifp); ifa_free(&ia->ia_ifa); return; } CURVNET_SET(ia->ia_ifa.ifa_ifp->if_vnet); /* * Drop lock while the ARP request is generated. */ IF_ADDR_WUNLOCK(ia->ia_ifa.ifa_ifp); arprequest(ia->ia_ifa.ifa_ifp, &IA_SIN(ia)->sin_addr, &IA_SIN(ia)->sin_addr, IF_LLADDR(ia->ia_ifa.ifa_ifp)); /* * Increment the count of retransmissions. If the count has reached the * maximum value, stop sending the GARP packets. Otherwise, schedule * the callout to retransmit another GARP packet. */ ++ia->ia_garp_count; if (ia->ia_garp_count >= garp_rexmit_count) { ifa_free(&ia->ia_ifa); } else { int rescheduled; IF_ADDR_WLOCK(ia->ia_ifa.ifa_ifp); rescheduled = callout_reset(&ia->ia_garp_timer, (1 << ia->ia_garp_count) * hz, garp_rexmit, ia); IF_ADDR_WUNLOCK(ia->ia_ifa.ifa_ifp); if (rescheduled) { ifa_free(&ia->ia_ifa); } } CURVNET_RESTORE(); } /* * Start the GARP retransmit timer. * * A single GARP is always transmitted when an IPv4 address is added * to an interface and that is usually sufficient. However, in some * circumstances, such as when a shared address is passed between * cluster nodes, this single GARP may occasionally be dropped or * lost. This can lead to neighbors on the network link working with a * stale ARP cache and sending packets destined for that address to * the node that previously owned the address, which may not respond. * * To avoid this situation, GARP retransmits can be enabled by setting * the net.link.ether.inet.garp_rexmit_count sysctl to a value greater * than zero. The setting represents the maximum number of * retransmissions. The interval between retransmissions is calculated * using an exponential backoff algorithm, doubling each time, so the * retransmission intervals are: {1, 2, 4, 8, 16, ...} (seconds). */ static void garp_timer_start(struct ifaddr *ifa) { struct in_ifaddr *ia = (struct in_ifaddr *) ifa; IF_ADDR_WLOCK(ia->ia_ifa.ifa_ifp); ia->ia_garp_count = 0; if (callout_reset(&ia->ia_garp_timer, (1 << ia->ia_garp_count) * hz, garp_rexmit, ia) == 0) { ifa_ref(ifa); } IF_ADDR_WUNLOCK(ia->ia_ifa.ifa_ifp); } void arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa) { struct epoch_tracker et; const struct sockaddr_in *dst_in; const struct sockaddr *dst; if (ifa->ifa_carp != NULL) return; dst = ifa->ifa_addr; dst_in = (const struct sockaddr_in *)dst; if (ntohl(dst_in->sin_addr.s_addr) == INADDR_ANY) return; NET_EPOCH_ENTER(et); arp_announce_ifaddr(ifp, dst_in->sin_addr, IF_LLADDR(ifp)); NET_EPOCH_EXIT(et); if (garp_rexmit_count > 0) { garp_timer_start(ifa); } arp_add_ifa_lle(ifp, dst); } void arp_announce_ifaddr(struct ifnet *ifp, struct in_addr addr, u_char *enaddr) { if (ntohl(addr.s_addr) != INADDR_ANY) arprequest(ifp, &addr, &addr, enaddr); } /* * Sends gratuitous ARPs for each ifaddr to notify other * nodes about the address change. */ static __noinline void arp_handle_ifllchange(struct ifnet *ifp) { struct ifaddr *ifa; CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family == AF_INET) arp_ifinit(ifp, ifa); } } /* * A handler for interface link layer address change event. */ static void arp_iflladdr(void *arg __unused, struct ifnet *ifp) { + /* if_bridge can update its lladdr during if_vmove(), after we've done + * if_detach_internal()/dom_ifdetach(). */ + if (ifp->if_afdata[AF_INET] == NULL) + return; lltable_update_ifaddr(LLTABLE(ifp)); if ((ifp->if_flags & IFF_UP) != 0) arp_handle_ifllchange(ifp); } static void vnet_arp_init(void) { if (IS_DEFAULT_VNET(curvnet)) { netisr_register(&arp_nh); iflladdr_tag = EVENTHANDLER_REGISTER(iflladdr_event, arp_iflladdr, NULL, EVENTHANDLER_PRI_ANY); } #ifdef VIMAGE else netisr_register_vnet(&arp_nh); #endif } VNET_SYSINIT(vnet_arp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_SECOND, vnet_arp_init, 0); #ifdef VIMAGE /* * We have to unregister ARP along with IP otherwise we risk doing INADDR_HASH * lookups after destroying the hash. Ideally this would go on SI_ORDER_3.5. */ static void vnet_arp_destroy(__unused void *arg) { netisr_unregister_vnet(&arp_nh); } VNET_SYSUNINIT(vnet_arp_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, vnet_arp_destroy, NULL); #endif diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c index 497c0bfc10e8..62f0ac733a23 100644 --- a/sys/netinet6/nd6.c +++ b/sys/netinet6/nd6.c @@ -1,2660 +1,2662 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * 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. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``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 PROJECT OR CONTRIBUTORS 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 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. * * $KAME: nd6.c,v 1.144 2001/05/24 07:44:00 itojun Exp $ */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.h" #include "opt_route.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */ #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */ #define SIN6(s) ((const struct sockaddr_in6 *)(s)) MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery"); /* timer values */ VNET_DEFINE(int, nd6_prune) = 1; /* walk list every 1 seconds */ VNET_DEFINE(int, nd6_delay) = 5; /* delay first probe time 5 second */ VNET_DEFINE(int, nd6_umaxtries) = 3; /* maximum unicast query */ VNET_DEFINE(int, nd6_mmaxtries) = 3; /* maximum multicast query */ VNET_DEFINE(int, nd6_useloopback) = 1; /* use loopback interface for * local traffic */ VNET_DEFINE(int, nd6_gctimer) = (60 * 60 * 24); /* 1 day: garbage * collection timer */ /* preventing too many loops in ND option parsing */ VNET_DEFINE_STATIC(int, nd6_maxndopt) = 10; /* max # of ND options allowed */ VNET_DEFINE(int, nd6_maxnudhint) = 0; /* max # of subsequent upper * layer hints */ VNET_DEFINE_STATIC(int, nd6_maxqueuelen) = 16; /* max pkts cached in unresolved * ND entries */ #define V_nd6_maxndopt VNET(nd6_maxndopt) #define V_nd6_maxqueuelen VNET(nd6_maxqueuelen) #ifdef ND6_DEBUG VNET_DEFINE(int, nd6_debug) = 1; #else VNET_DEFINE(int, nd6_debug) = 0; #endif static eventhandler_tag lle_event_eh, iflladdr_event_eh, ifnet_link_event_eh; VNET_DEFINE(struct nd_prhead, nd_prefix); VNET_DEFINE(struct rwlock, nd6_lock); VNET_DEFINE(uint64_t, nd6_list_genid); VNET_DEFINE(struct mtx, nd6_onlink_mtx); VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL; #define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval) int (*send_sendso_input_hook)(struct mbuf *, struct ifnet *, int, int); static int nd6_is_new_addr_neighbor(const struct sockaddr_in6 *, struct ifnet *); static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); static void nd6_slowtimo(void *); static int regen_tmpaddr(struct in6_ifaddr *); static void nd6_free(struct llentry **, int); static void nd6_free_redirect(const struct llentry *); static void nd6_llinfo_timer(void *); static void nd6_llinfo_settimer_locked(struct llentry *, long); static void clear_llinfo_pqueue(struct llentry *); static int nd6_resolve_slow(struct ifnet *, int, struct mbuf *, const struct sockaddr_in6 *, u_char *, uint32_t *, struct llentry **); static int nd6_need_cache(struct ifnet *); VNET_DEFINE_STATIC(struct callout, nd6_slowtimo_ch); #define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch) VNET_DEFINE_STATIC(struct callout, nd6_timer_ch); #define V_nd6_timer_ch VNET(nd6_timer_ch) SYSCTL_DECL(_net_inet6_icmp6); static void nd6_lle_event(void *arg __unused, struct llentry *lle, int evt) { struct rt_addrinfo rtinfo; struct sockaddr_in6 dst; struct sockaddr_dl gw; struct ifnet *ifp; int type; int fibnum; LLE_WLOCK_ASSERT(lle); if (lltable_get_af(lle->lle_tbl) != AF_INET6) return; switch (evt) { case LLENTRY_RESOLVED: type = RTM_ADD; KASSERT(lle->la_flags & LLE_VALID, ("%s: %p resolved but not valid?", __func__, lle)); break; case LLENTRY_EXPIRED: type = RTM_DELETE; break; default: return; } ifp = lltable_get_ifp(lle->lle_tbl); bzero(&dst, sizeof(dst)); bzero(&gw, sizeof(gw)); bzero(&rtinfo, sizeof(rtinfo)); lltable_fill_sa_entry(lle, (struct sockaddr *)&dst); dst.sin6_scope_id = in6_getscopezone(ifp, in6_addrscope(&dst.sin6_addr)); gw.sdl_len = sizeof(struct sockaddr_dl); gw.sdl_family = AF_LINK; gw.sdl_alen = ifp->if_addrlen; gw.sdl_index = ifp->if_index; gw.sdl_type = ifp->if_type; if (evt == LLENTRY_RESOLVED) bcopy(lle->ll_addr, gw.sdl_data, ifp->if_addrlen); rtinfo.rti_info[RTAX_DST] = (struct sockaddr *)&dst; rtinfo.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&gw; rtinfo.rti_addrs = RTA_DST | RTA_GATEWAY; fibnum = V_rt_add_addr_allfibs ? RT_ALL_FIBS : ifp->if_fib; rt_missmsg_fib(type, &rtinfo, RTF_HOST | RTF_LLDATA | ( type == RTM_ADD ? RTF_UP: 0), 0, fibnum); } /* * A handler for interface link layer address change event. */ static void nd6_iflladdr(void *arg __unused, struct ifnet *ifp) { + if (ifp->if_afdata[AF_INET6] == NULL) + return; lltable_update_ifaddr(LLTABLE6(ifp)); } void nd6_init(void) { mtx_init(&V_nd6_onlink_mtx, "nd6 onlink", NULL, MTX_DEF); rw_init(&V_nd6_lock, "nd6 list"); LIST_INIT(&V_nd_prefix); nd6_defrouter_init(); /* Start timers. */ callout_init(&V_nd6_slowtimo_ch, 0); callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, nd6_slowtimo, curvnet); callout_init(&V_nd6_timer_ch, 0); callout_reset(&V_nd6_timer_ch, hz, nd6_timer, curvnet); nd6_dad_init(); if (IS_DEFAULT_VNET(curvnet)) { lle_event_eh = EVENTHANDLER_REGISTER(lle_event, nd6_lle_event, NULL, EVENTHANDLER_PRI_ANY); iflladdr_event_eh = EVENTHANDLER_REGISTER(iflladdr_event, nd6_iflladdr, NULL, EVENTHANDLER_PRI_ANY); ifnet_link_event_eh = EVENTHANDLER_REGISTER(ifnet_link_event, nd6_ifnet_link_event, NULL, EVENTHANDLER_PRI_ANY); } } #ifdef VIMAGE void nd6_destroy() { callout_drain(&V_nd6_slowtimo_ch); callout_drain(&V_nd6_timer_ch); if (IS_DEFAULT_VNET(curvnet)) { EVENTHANDLER_DEREGISTER(ifnet_link_event, ifnet_link_event_eh); EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh); EVENTHANDLER_DEREGISTER(iflladdr_event, iflladdr_event_eh); } rw_destroy(&V_nd6_lock); mtx_destroy(&V_nd6_onlink_mtx); } #endif struct nd_ifinfo * nd6_ifattach(struct ifnet *ifp) { struct nd_ifinfo *nd; nd = malloc(sizeof(*nd), M_IP6NDP, M_WAITOK | M_ZERO); nd->initialized = 1; nd->chlim = IPV6_DEFHLIM; nd->basereachable = REACHABLE_TIME; nd->reachable = ND_COMPUTE_RTIME(nd->basereachable); nd->retrans = RETRANS_TIMER; nd->flags = ND6_IFF_PERFORMNUD; /* Set IPv6 disabled on all interfaces but loopback by default. */ if ((ifp->if_flags & IFF_LOOPBACK) == 0) nd->flags |= ND6_IFF_IFDISABLED; /* A loopback interface always has ND6_IFF_AUTO_LINKLOCAL. * XXXHRS: Clear ND6_IFF_AUTO_LINKLOCAL on an IFT_BRIDGE interface by * default regardless of the V_ip6_auto_linklocal configuration to * give a reasonable default behavior. */ if ((V_ip6_auto_linklocal && ifp->if_type != IFT_BRIDGE) || (ifp->if_flags & IFF_LOOPBACK)) nd->flags |= ND6_IFF_AUTO_LINKLOCAL; /* * A loopback interface does not need to accept RTADV. * XXXHRS: Clear ND6_IFF_ACCEPT_RTADV on an IFT_BRIDGE interface by * default regardless of the V_ip6_accept_rtadv configuration to * prevent the interface from accepting RA messages arrived * on one of the member interfaces with ND6_IFF_ACCEPT_RTADV. */ if (V_ip6_accept_rtadv && !(ifp->if_flags & IFF_LOOPBACK) && (ifp->if_type != IFT_BRIDGE)) { nd->flags |= ND6_IFF_ACCEPT_RTADV; /* If we globally accept rtadv, assume IPv6 on. */ nd->flags &= ~ND6_IFF_IFDISABLED; } if (V_ip6_no_radr && !(ifp->if_flags & IFF_LOOPBACK)) nd->flags |= ND6_IFF_NO_RADR; /* XXX: we cannot call nd6_setmtu since ifp is not fully initialized */ nd6_setmtu0(ifp, nd); return nd; } void nd6_ifdetach(struct ifnet *ifp, struct nd_ifinfo *nd) { struct epoch_tracker et; struct ifaddr *ifa, *next; NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, next) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; /* stop DAD processing */ nd6_dad_stop(ifa); } NET_EPOCH_EXIT(et); free(nd, M_IP6NDP); } /* * Reset ND level link MTU. This function is called when the physical MTU * changes, which means we might have to adjust the ND level MTU. */ void nd6_setmtu(struct ifnet *ifp) { if (ifp->if_afdata[AF_INET6] == NULL) return; nd6_setmtu0(ifp, ND_IFINFO(ifp)); } /* XXX todo: do not maintain copy of ifp->if_mtu in ndi->maxmtu */ void nd6_setmtu0(struct ifnet *ifp, struct nd_ifinfo *ndi) { u_int32_t omaxmtu; omaxmtu = ndi->maxmtu; ndi->maxmtu = ifp->if_mtu; /* * Decreasing the interface MTU under IPV6 minimum MTU may cause * undesirable situation. We thus notify the operator of the change * explicitly. The check for omaxmtu is necessary to restrict the * log to the case of changing the MTU, not initializing it. */ if (omaxmtu >= IPV6_MMTU && ndi->maxmtu < IPV6_MMTU) { log(LOG_NOTICE, "nd6_setmtu0: " "new link MTU on %s (%lu) is too small for IPv6\n", if_name(ifp), (unsigned long)ndi->maxmtu); } if (ndi->maxmtu > V_in6_maxmtu) in6_setmaxmtu(); /* check all interfaces just in case */ } void nd6_option_init(void *opt, int icmp6len, union nd_opts *ndopts) { bzero(ndopts, sizeof(*ndopts)); ndopts->nd_opts_search = (struct nd_opt_hdr *)opt; ndopts->nd_opts_last = (struct nd_opt_hdr *)(((u_char *)opt) + icmp6len); if (icmp6len == 0) { ndopts->nd_opts_done = 1; ndopts->nd_opts_search = NULL; } } /* * Take one ND option. */ struct nd_opt_hdr * nd6_option(union nd_opts *ndopts) { struct nd_opt_hdr *nd_opt; int olen; KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", __func__)); if (ndopts->nd_opts_search == NULL) return NULL; if (ndopts->nd_opts_done) return NULL; nd_opt = ndopts->nd_opts_search; /* make sure nd_opt_len is inside the buffer */ if ((caddr_t)&nd_opt->nd_opt_len >= (caddr_t)ndopts->nd_opts_last) { bzero(ndopts, sizeof(*ndopts)); return NULL; } olen = nd_opt->nd_opt_len << 3; if (olen == 0) { /* * Message validation requires that all included * options have a length that is greater than zero. */ bzero(ndopts, sizeof(*ndopts)); return NULL; } ndopts->nd_opts_search = (struct nd_opt_hdr *)((caddr_t)nd_opt + olen); if (ndopts->nd_opts_search > ndopts->nd_opts_last) { /* option overruns the end of buffer, invalid */ bzero(ndopts, sizeof(*ndopts)); return NULL; } else if (ndopts->nd_opts_search == ndopts->nd_opts_last) { /* reached the end of options chain */ ndopts->nd_opts_done = 1; ndopts->nd_opts_search = NULL; } return nd_opt; } /* * Parse multiple ND options. * This function is much easier to use, for ND routines that do not need * multiple options of the same type. */ int nd6_options(union nd_opts *ndopts) { struct nd_opt_hdr *nd_opt; int i = 0; KASSERT(ndopts != NULL, ("%s: ndopts == NULL", __func__)); KASSERT(ndopts->nd_opts_last != NULL, ("%s: uninitialized ndopts", __func__)); if (ndopts->nd_opts_search == NULL) return 0; while (1) { nd_opt = nd6_option(ndopts); if (nd_opt == NULL && ndopts->nd_opts_last == NULL) { /* * Message validation requires that all included * options have a length that is greater than zero. */ ICMP6STAT_INC(icp6s_nd_badopt); bzero(ndopts, sizeof(*ndopts)); return -1; } if (nd_opt == NULL) goto skip1; switch (nd_opt->nd_opt_type) { case ND_OPT_SOURCE_LINKADDR: case ND_OPT_TARGET_LINKADDR: case ND_OPT_MTU: case ND_OPT_REDIRECTED_HEADER: case ND_OPT_NONCE: if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) { nd6log((LOG_INFO, "duplicated ND6 option found (type=%d)\n", nd_opt->nd_opt_type)); /* XXX bark? */ } else { ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; } break; case ND_OPT_PREFIX_INFORMATION: if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0) { ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt; } ndopts->nd_opts_pi_end = (struct nd_opt_prefix_info *)nd_opt; break; /* What about ND_OPT_ROUTE_INFO? RFC 4191 */ case ND_OPT_RDNSS: /* RFC 6106 */ case ND_OPT_DNSSL: /* RFC 6106 */ /* * Silently ignore options we know and do not care about * in the kernel. */ break; default: /* * Unknown options must be silently ignored, * to accommodate future extension to the protocol. */ nd6log((LOG_DEBUG, "nd6_options: unsupported option %d - " "option ignored\n", nd_opt->nd_opt_type)); } skip1: i++; if (i > V_nd6_maxndopt) { ICMP6STAT_INC(icp6s_nd_toomanyopt); nd6log((LOG_INFO, "too many loop in nd opt\n")); break; } if (ndopts->nd_opts_done) break; } return 0; } /* * ND6 timer routine to handle ND6 entries */ static void nd6_llinfo_settimer_locked(struct llentry *ln, long tick) { int canceled; LLE_WLOCK_ASSERT(ln); if (tick < 0) { ln->la_expire = 0; ln->ln_ntick = 0; canceled = callout_stop(&ln->lle_timer); } else { ln->la_expire = time_uptime + tick / hz; LLE_ADDREF(ln); if (tick > INT_MAX) { ln->ln_ntick = tick - INT_MAX; canceled = callout_reset(&ln->lle_timer, INT_MAX, nd6_llinfo_timer, ln); } else { ln->ln_ntick = 0; canceled = callout_reset(&ln->lle_timer, tick, nd6_llinfo_timer, ln); } } if (canceled > 0) LLE_REMREF(ln); } /* * Gets source address of the first packet in hold queue * and stores it in @src. * Returns pointer to @src (if hold queue is not empty) or NULL. * * Set noinline to be dtrace-friendly */ static __noinline struct in6_addr * nd6_llinfo_get_holdsrc(struct llentry *ln, struct in6_addr *src) { struct ip6_hdr hdr; struct mbuf *m; if (ln->la_hold == NULL) return (NULL); /* * assume every packet in la_hold has the same IP header */ m = ln->la_hold; if (sizeof(hdr) > m->m_len) return (NULL); m_copydata(m, 0, sizeof(hdr), (caddr_t)&hdr); *src = hdr.ip6_src; return (src); } /* * Checks if we need to switch from STALE state. * * RFC 4861 requires switching from STALE to DELAY state * on first packet matching entry, waiting V_nd6_delay and * transition to PROBE state (if upper layer confirmation was * not received). * * This code performs a bit differently: * On packet hit we don't change state (but desired state * can be guessed by control plane). However, after V_nd6_delay * seconds code will transition to PROBE state (so DELAY state * is kinda skipped in most situations). * * Typically, V_nd6_gctimer is bigger than V_nd6_delay, so * we perform the following upon entering STALE state: * * 1) Arm timer to run each V_nd6_delay seconds to make sure that * if packet was transmitted at the start of given interval, we * would be able to switch to PROBE state in V_nd6_delay seconds * as user expects. * * 2) Reschedule timer until original V_nd6_gctimer expires keeping * lle in STALE state (remaining timer value stored in lle_remtime). * * 3) Reschedule timer if packet was transmitted less that V_nd6_delay * seconds ago. * * Returns non-zero value if the entry is still STALE (storing * the next timer interval in @pdelay). * * Returns zero value if original timer expired or we need to switch to * PROBE (store that in @do_switch variable). */ static int nd6_is_stale(struct llentry *lle, long *pdelay, int *do_switch) { int nd_delay, nd_gctimer, r_skip_req; time_t lle_hittime; long delay; *do_switch = 0; nd_gctimer = V_nd6_gctimer; nd_delay = V_nd6_delay; LLE_REQ_LOCK(lle); r_skip_req = lle->r_skip_req; lle_hittime = lle->lle_hittime; LLE_REQ_UNLOCK(lle); if (r_skip_req > 0) { /* * Nonzero r_skip_req value was set upon entering * STALE state. Since value was not changed, no * packets were passed using this lle. Ask for * timer reschedule and keep STALE state. */ delay = (long)(MIN(nd_gctimer, nd_delay)); delay *= hz; if (lle->lle_remtime > delay) lle->lle_remtime -= delay; else { delay = lle->lle_remtime; lle->lle_remtime = 0; } if (delay == 0) { /* * The original ng6_gctime timeout ended, * no more rescheduling. */ return (0); } *pdelay = delay; return (1); } /* * Packet received. Verify timestamp */ delay = (long)(time_uptime - lle_hittime); if (delay < nd_delay) { /* * V_nd6_delay still not passed since the first * hit in STALE state. * Reshedule timer and return. */ *pdelay = (long)(nd_delay - delay) * hz; return (1); } /* Request switching to probe */ *do_switch = 1; return (0); } /* * Switch @lle state to new state optionally arming timers. * * Set noinline to be dtrace-friendly */ __noinline void nd6_llinfo_setstate(struct llentry *lle, int newstate) { struct ifnet *ifp; int nd_gctimer, nd_delay; long delay, remtime; delay = 0; remtime = 0; switch (newstate) { case ND6_LLINFO_INCOMPLETE: ifp = lle->lle_tbl->llt_ifp; delay = (long)ND_IFINFO(ifp)->retrans * hz / 1000; break; case ND6_LLINFO_REACHABLE: if (!ND6_LLINFO_PERMANENT(lle)) { ifp = lle->lle_tbl->llt_ifp; delay = (long)ND_IFINFO(ifp)->reachable * hz; } break; case ND6_LLINFO_STALE: /* * Notify fast path that we want to know if any packet * is transmitted by setting r_skip_req. */ LLE_REQ_LOCK(lle); lle->r_skip_req = 1; LLE_REQ_UNLOCK(lle); nd_delay = V_nd6_delay; nd_gctimer = V_nd6_gctimer; delay = (long)(MIN(nd_gctimer, nd_delay)) * hz; remtime = (long)nd_gctimer * hz - delay; break; case ND6_LLINFO_DELAY: lle->la_asked = 0; delay = (long)V_nd6_delay * hz; break; } if (delay > 0) nd6_llinfo_settimer_locked(lle, delay); lle->lle_remtime = remtime; lle->ln_state = newstate; } /* * Timer-dependent part of nd state machine. * * Set noinline to be dtrace-friendly */ static __noinline void nd6_llinfo_timer(void *arg) { struct epoch_tracker et; struct llentry *ln; struct in6_addr *dst, *pdst, *psrc, src; struct ifnet *ifp; struct nd_ifinfo *ndi; int do_switch, send_ns; long delay; KASSERT(arg != NULL, ("%s: arg NULL", __func__)); ln = (struct llentry *)arg; ifp = lltable_get_ifp(ln->lle_tbl); CURVNET_SET(ifp->if_vnet); ND6_RLOCK(); LLE_WLOCK(ln); if (callout_pending(&ln->lle_timer)) { /* * Here we are a bit odd here in the treatment of * active/pending. If the pending bit is set, it got * rescheduled before I ran. The active * bit we ignore, since if it was stopped * in ll_tablefree() and was currently running * it would have return 0 so the code would * not have deleted it since the callout could * not be stopped so we want to go through * with the delete here now. If the callout * was restarted, the pending bit will be back on and * we just want to bail since the callout_reset would * return 1 and our reference would have been removed * by nd6_llinfo_settimer_locked above since canceled * would have been 1. */ LLE_WUNLOCK(ln); ND6_RUNLOCK(); CURVNET_RESTORE(); return; } NET_EPOCH_ENTER(et); ndi = ND_IFINFO(ifp); send_ns = 0; dst = &ln->r_l3addr.addr6; pdst = dst; if (ln->ln_ntick > 0) { if (ln->ln_ntick > INT_MAX) { ln->ln_ntick -= INT_MAX; nd6_llinfo_settimer_locked(ln, INT_MAX); } else { ln->ln_ntick = 0; nd6_llinfo_settimer_locked(ln, ln->ln_ntick); } goto done; } if (ln->la_flags & LLE_STATIC) { goto done; } if (ln->la_flags & LLE_DELETED) { nd6_free(&ln, 0); goto done; } switch (ln->ln_state) { case ND6_LLINFO_INCOMPLETE: if (ln->la_asked < V_nd6_mmaxtries) { ln->la_asked++; send_ns = 1; /* Send NS to multicast address */ pdst = NULL; } else { struct mbuf *m = ln->la_hold; if (m) { struct mbuf *m0; /* * assuming every packet in la_hold has the * same IP header. Send error after unlock. */ m0 = m->m_nextpkt; m->m_nextpkt = NULL; ln->la_hold = m0; clear_llinfo_pqueue(ln); } nd6_free(&ln, 0); if (m != NULL) { struct mbuf *n = m; /* * if there are any ummapped mbufs, we * must free them, rather than using * them for an ICMP, as they cannot be * checksummed. */ while ((n = n->m_next) != NULL) { if (n->m_flags & M_EXTPG) break; } if (n != NULL) { m_freem(m); m = NULL; } else { icmp6_error2(m, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR, 0, ifp); } } } break; case ND6_LLINFO_REACHABLE: if (!ND6_LLINFO_PERMANENT(ln)) nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); break; case ND6_LLINFO_STALE: if (nd6_is_stale(ln, &delay, &do_switch) != 0) { /* * No packet has used this entry and GC timeout * has not been passed. Reshedule timer and * return. */ nd6_llinfo_settimer_locked(ln, delay); break; } if (do_switch == 0) { /* * GC timer has ended and entry hasn't been used. * Run Garbage collector (RFC 4861, 5.3) */ if (!ND6_LLINFO_PERMANENT(ln)) nd6_free(&ln, 1); break; } /* Entry has been used AND delay timer has ended. */ /* FALLTHROUGH */ case ND6_LLINFO_DELAY: if (ndi && (ndi->flags & ND6_IFF_PERFORMNUD) != 0) { /* We need NUD */ ln->la_asked = 1; nd6_llinfo_setstate(ln, ND6_LLINFO_PROBE); send_ns = 1; } else nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); /* XXX */ break; case ND6_LLINFO_PROBE: if (ln->la_asked < V_nd6_umaxtries) { ln->la_asked++; send_ns = 1; } else { nd6_free(&ln, 0); } break; default: panic("%s: paths in a dark night can be confusing: %d", __func__, ln->ln_state); } done: if (ln != NULL) ND6_RUNLOCK(); if (send_ns != 0) { nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); psrc = nd6_llinfo_get_holdsrc(ln, &src); LLE_FREE_LOCKED(ln); ln = NULL; nd6_ns_output(ifp, psrc, pdst, dst, NULL); } if (ln != NULL) LLE_FREE_LOCKED(ln); NET_EPOCH_EXIT(et); CURVNET_RESTORE(); } /* * ND6 timer routine to expire default route list and prefix list */ void nd6_timer(void *arg) { CURVNET_SET((struct vnet *) arg); struct epoch_tracker et; struct nd_prhead prl; struct nd_prefix *pr, *npr; struct ifnet *ifp; struct in6_ifaddr *ia6, *nia6; uint64_t genid; LIST_INIT(&prl); NET_EPOCH_ENTER(et); nd6_defrouter_timer(); /* * expire interface addresses. * in the past the loop was inside prefix expiry processing. * However, from a stricter speci-confrmance standpoint, we should * rather separate address lifetimes and prefix lifetimes. * * XXXRW: in6_ifaddrhead locking. */ addrloop: CK_STAILQ_FOREACH_SAFE(ia6, &V_in6_ifaddrhead, ia_link, nia6) { /* check address lifetime */ if (IFA6_IS_INVALID(ia6)) { int regen = 0; /* * If the expiring address is temporary, try * regenerating a new one. This would be useful when * we suspended a laptop PC, then turned it on after a * period that could invalidate all temporary * addresses. Although we may have to restart the * loop (see below), it must be after purging the * address. Otherwise, we'd see an infinite loop of * regeneration. */ if (V_ip6_use_tempaddr && (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0) { if (regen_tmpaddr(ia6) == 0) regen = 1; } in6_purgeaddr(&ia6->ia_ifa); if (regen) goto addrloop; /* XXX: see below */ } else if (IFA6_IS_DEPRECATED(ia6)) { int oldflags = ia6->ia6_flags; ia6->ia6_flags |= IN6_IFF_DEPRECATED; /* * If a temporary address has just become deprecated, * regenerate a new one if possible. */ if (V_ip6_use_tempaddr && (ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && (oldflags & IN6_IFF_DEPRECATED) == 0) { if (regen_tmpaddr(ia6) == 0) { /* * A new temporary address is * generated. * XXX: this means the address chain * has changed while we are still in * the loop. Although the change * would not cause disaster (because * it's not a deletion, but an * addition,) we'd rather restart the * loop just for safety. Or does this * significantly reduce performance?? */ goto addrloop; } } } else if ((ia6->ia6_flags & IN6_IFF_TENTATIVE) != 0) { /* * Schedule DAD for a tentative address. This happens * if the interface was down or not running * when the address was configured. */ int delay; delay = arc4random() % (MAX_RTR_SOLICITATION_DELAY * hz); nd6_dad_start((struct ifaddr *)ia6, delay); } else { /* * Check status of the interface. If it is down, * mark the address as tentative for future DAD. */ ifp = ia6->ia_ifp; if ((ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0 && ((ifp->if_flags & IFF_UP) == 0 || (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || (ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) != 0)){ ia6->ia6_flags &= ~IN6_IFF_DUPLICATED; ia6->ia6_flags |= IN6_IFF_TENTATIVE; } /* * A new RA might have made a deprecated address * preferred. */ ia6->ia6_flags &= ~IN6_IFF_DEPRECATED; } } NET_EPOCH_EXIT(et); ND6_WLOCK(); restart: LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { /* * Expire prefixes. Since the pltime is only used for * autoconfigured addresses, pltime processing for prefixes is * not necessary. * * Only unlink after all derived addresses have expired. This * may not occur until two hours after the prefix has expired * per RFC 4862. If the prefix expires before its derived * addresses, mark it off-link. This will be done automatically * after unlinking if no address references remain. */ if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME || time_uptime - pr->ndpr_lastupdate <= pr->ndpr_vltime) continue; if (pr->ndpr_addrcnt == 0) { nd6_prefix_unlink(pr, &prl); continue; } if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) { genid = V_nd6_list_genid; nd6_prefix_ref(pr); ND6_WUNLOCK(); ND6_ONLINK_LOCK(); (void)nd6_prefix_offlink(pr); ND6_ONLINK_UNLOCK(); ND6_WLOCK(); nd6_prefix_rele(pr); if (genid != V_nd6_list_genid) goto restart; } } ND6_WUNLOCK(); while ((pr = LIST_FIRST(&prl)) != NULL) { LIST_REMOVE(pr, ndpr_entry); nd6_prefix_del(pr); } callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz, nd6_timer, curvnet); CURVNET_RESTORE(); } /* * ia6 - deprecated/invalidated temporary address */ static int regen_tmpaddr(struct in6_ifaddr *ia6) { struct ifaddr *ifa; struct ifnet *ifp; struct in6_ifaddr *public_ifa6 = NULL; NET_EPOCH_ASSERT(); ifp = ia6->ia_ifa.ifa_ifp; CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { struct in6_ifaddr *it6; if (ifa->ifa_addr->sa_family != AF_INET6) continue; it6 = (struct in6_ifaddr *)ifa; /* ignore no autoconf addresses. */ if ((it6->ia6_flags & IN6_IFF_AUTOCONF) == 0) continue; /* ignore autoconf addresses with different prefixes. */ if (it6->ia6_ndpr == NULL || it6->ia6_ndpr != ia6->ia6_ndpr) continue; /* * Now we are looking at an autoconf address with the same * prefix as ours. If the address is temporary and is still * preferred, do not create another one. It would be rare, but * could happen, for example, when we resume a laptop PC after * a long period. */ if ((it6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && !IFA6_IS_DEPRECATED(it6)) { public_ifa6 = NULL; break; } /* * This is a public autoconf address that has the same prefix * as ours. If it is preferred, keep it. We can't break the * loop here, because there may be a still-preferred temporary * address with the prefix. */ if (!IFA6_IS_DEPRECATED(it6)) public_ifa6 = it6; } if (public_ifa6 != NULL) ifa_ref(&public_ifa6->ia_ifa); if (public_ifa6 != NULL) { int e; if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) { ifa_free(&public_ifa6->ia_ifa); log(LOG_NOTICE, "regen_tmpaddr: failed to create a new" " tmp addr,errno=%d\n", e); return (-1); } ifa_free(&public_ifa6->ia_ifa); return (0); } return (-1); } /* * Remove prefix and default router list entries corresponding to ifp. Neighbor * cache entries are freed in in6_domifdetach(). */ void nd6_purge(struct ifnet *ifp) { struct nd_prhead prl; struct nd_prefix *pr, *npr; LIST_INIT(&prl); /* Purge default router list entries toward ifp. */ nd6_defrouter_purge(ifp); ND6_WLOCK(); /* * Remove prefixes on ifp. We should have already removed addresses on * this interface, so no addresses should be referencing these prefixes. */ LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) { if (pr->ndpr_ifp == ifp) nd6_prefix_unlink(pr, &prl); } ND6_WUNLOCK(); /* Delete the unlinked prefix objects. */ while ((pr = LIST_FIRST(&prl)) != NULL) { LIST_REMOVE(pr, ndpr_entry); nd6_prefix_del(pr); } /* cancel default outgoing interface setting */ if (V_nd6_defifindex == ifp->if_index) nd6_setdefaultiface(0); if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { /* Refresh default router list. */ defrouter_select_fib(ifp->if_fib); } } /* * the caller acquires and releases the lock on the lltbls * Returns the llentry locked */ struct llentry * nd6_lookup(const struct in6_addr *addr6, int flags, struct ifnet *ifp) { struct sockaddr_in6 sin6; struct llentry *ln; bzero(&sin6, sizeof(sin6)); sin6.sin6_len = sizeof(struct sockaddr_in6); sin6.sin6_family = AF_INET6; sin6.sin6_addr = *addr6; IF_AFDATA_LOCK_ASSERT(ifp); ln = lla_lookup(LLTABLE6(ifp), flags, (struct sockaddr *)&sin6); return (ln); } static struct llentry * nd6_alloc(const struct in6_addr *addr6, int flags, struct ifnet *ifp) { struct sockaddr_in6 sin6; struct llentry *ln; bzero(&sin6, sizeof(sin6)); sin6.sin6_len = sizeof(struct sockaddr_in6); sin6.sin6_family = AF_INET6; sin6.sin6_addr = *addr6; ln = lltable_alloc_entry(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6); if (ln != NULL) ln->ln_state = ND6_LLINFO_NOSTATE; return (ln); } /* * Test whether a given IPv6 address is a neighbor or not, ignoring * the actual neighbor cache. The neighbor cache is ignored in order * to not reenter the routing code from within itself. */ static int nd6_is_new_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) { struct nd_prefix *pr; struct ifaddr *ifa; struct rt_addrinfo info; struct sockaddr_in6 rt_key; const struct sockaddr *dst6; uint64_t genid; int error, fibnum; /* * A link-local address is always a neighbor. * XXX: a link does not necessarily specify a single interface. */ if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) { struct sockaddr_in6 sin6_copy; u_int32_t zone; /* * We need sin6_copy since sa6_recoverscope() may modify the * content (XXX). */ sin6_copy = *addr; if (sa6_recoverscope(&sin6_copy)) return (0); /* XXX: should be impossible */ if (in6_setscope(&sin6_copy.sin6_addr, ifp, &zone)) return (0); if (sin6_copy.sin6_scope_id == zone) return (1); else return (0); } bzero(&rt_key, sizeof(rt_key)); bzero(&info, sizeof(info)); info.rti_info[RTAX_DST] = (struct sockaddr *)&rt_key; /* * If the address matches one of our addresses, * it should be a neighbor. * If the address matches one of our on-link prefixes, it should be a * neighbor. */ ND6_RLOCK(); restart: LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { if (pr->ndpr_ifp != ifp) continue; if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) { dst6 = (const struct sockaddr *)&pr->ndpr_prefix; /* * We only need to check all FIBs if add_addr_allfibs * is unset. If set, checking any FIB will suffice. */ fibnum = V_rt_add_addr_allfibs ? rt_numfibs - 1 : 0; for (; fibnum < rt_numfibs; fibnum++) { genid = V_nd6_list_genid; ND6_RUNLOCK(); /* * Restore length field before * retrying lookup */ rt_key.sin6_len = sizeof(rt_key); error = rib_lookup_info(fibnum, dst6, 0, 0, &info); ND6_RLOCK(); if (genid != V_nd6_list_genid) goto restart; if (error == 0) break; } if (error != 0) continue; /* * This is the case where multiple interfaces * have the same prefix, but only one is installed * into the routing table and that prefix entry * is not the one being examined here. */ if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, &rt_key.sin6_addr)) continue; } if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr, &addr->sin6_addr, &pr->ndpr_mask)) { ND6_RUNLOCK(); return (1); } } ND6_RUNLOCK(); /* * If the address is assigned on the node of the other side of * a p2p interface, the address should be a neighbor. */ if (ifp->if_flags & IFF_POINTOPOINT) { struct epoch_tracker et; NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != addr->sin6_family) continue; if (ifa->ifa_dstaddr != NULL && sa_equal(addr, ifa->ifa_dstaddr)) { NET_EPOCH_EXIT(et); return 1; } } NET_EPOCH_EXIT(et); } /* * If the default router list is empty, all addresses are regarded * as on-link, and thus, as a neighbor. */ if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV && nd6_defrouter_list_empty() && V_nd6_defifindex == ifp->if_index) { return (1); } return (0); } /* * Detect if a given IPv6 address identifies a neighbor on a given link. * XXX: should take care of the destination of a p2p link? */ int nd6_is_addr_neighbor(const struct sockaddr_in6 *addr, struct ifnet *ifp) { struct llentry *lle; int rc = 0; NET_EPOCH_ASSERT(); IF_AFDATA_UNLOCK_ASSERT(ifp); if (nd6_is_new_addr_neighbor(addr, ifp)) return (1); /* * Even if the address matches none of our addresses, it might be * in the neighbor cache. */ if ((lle = nd6_lookup(&addr->sin6_addr, 0, ifp)) != NULL) { LLE_RUNLOCK(lle); rc = 1; } return (rc); } /* * Free an nd6 llinfo entry. * Since the function would cause significant changes in the kernel, DO NOT * make it global, unless you have a strong reason for the change, and are sure * that the change is safe. * * Set noinline to be dtrace-friendly */ static __noinline void nd6_free(struct llentry **lnp, int gc) { struct ifnet *ifp; struct llentry *ln; struct nd_defrouter *dr; ln = *lnp; *lnp = NULL; LLE_WLOCK_ASSERT(ln); ND6_RLOCK_ASSERT(); ifp = lltable_get_ifp(ln->lle_tbl); if ((ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) != 0) dr = defrouter_lookup_locked(&ln->r_l3addr.addr6, ifp); else dr = NULL; ND6_RUNLOCK(); if ((ln->la_flags & LLE_DELETED) == 0) EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); /* * we used to have pfctlinput(PRC_HOSTDEAD) here. * even though it is not harmful, it was not really necessary. */ /* cancel timer */ nd6_llinfo_settimer_locked(ln, -1); if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { if (dr != NULL && dr->expire && ln->ln_state == ND6_LLINFO_STALE && gc) { /* * If the reason for the deletion is just garbage * collection, and the neighbor is an active default * router, do not delete it. Instead, reset the GC * timer using the router's lifetime. * Simply deleting the entry would affect default * router selection, which is not necessarily a good * thing, especially when we're using router preference * values. * XXX: the check for ln_state would be redundant, * but we intentionally keep it just in case. */ if (dr->expire > time_uptime) nd6_llinfo_settimer_locked(ln, (dr->expire - time_uptime) * hz); else nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); LLE_REMREF(ln); LLE_WUNLOCK(ln); defrouter_rele(dr); return; } if (dr) { /* * Unreachablity of a router might affect the default * router selection and on-link detection of advertised * prefixes. */ /* * Temporarily fake the state to choose a new default * router and to perform on-link determination of * prefixes correctly. * Below the state will be set correctly, * or the entry itself will be deleted. */ ln->ln_state = ND6_LLINFO_INCOMPLETE; } if (ln->ln_router || dr) { /* * We need to unlock to avoid a LOR with rt6_flush() with the * rnh and for the calls to pfxlist_onlink_check() and * defrouter_select_fib() in the block further down for calls * into nd6_lookup(). We still hold a ref. */ LLE_WUNLOCK(ln); /* * rt6_flush must be called whether or not the neighbor * is in the Default Router List. * See a corresponding comment in nd6_na_input(). */ rt6_flush(&ln->r_l3addr.addr6, ifp); } if (dr) { /* * Since defrouter_select_fib() does not affect the * on-link determination and MIP6 needs the check * before the default router selection, we perform * the check now. */ pfxlist_onlink_check(); /* * Refresh default router list. */ defrouter_select_fib(dr->ifp->if_fib); } /* * If this entry was added by an on-link redirect, remove the * corresponding host route. */ if (ln->la_flags & LLE_REDIRECT) nd6_free_redirect(ln); if (ln->ln_router || dr) LLE_WLOCK(ln); } /* * Save to unlock. We still hold an extra reference and will not * free(9) in llentry_free() if someone else holds one as well. */ LLE_WUNLOCK(ln); IF_AFDATA_LOCK(ifp); LLE_WLOCK(ln); /* Guard against race with other llentry_free(). */ if (ln->la_flags & LLE_LINKED) { /* Remove callout reference */ LLE_REMREF(ln); lltable_unlink_entry(ln->lle_tbl, ln); } IF_AFDATA_UNLOCK(ifp); llentry_free(ln); if (dr != NULL) defrouter_rele(dr); } static int nd6_isdynrte(const struct rtentry *rt, const struct nhop_object *nh, void *xap) { if (nh->nh_flags & NHF_REDIRECT) return (1); return (0); } /* * Remove the rtentry for the given llentry, * both of which were installed by a redirect. */ static void nd6_free_redirect(const struct llentry *ln) { int fibnum; struct sockaddr_in6 sin6; struct rt_addrinfo info; struct rib_cmd_info rc; struct epoch_tracker et; lltable_fill_sa_entry(ln, (struct sockaddr *)&sin6); memset(&info, 0, sizeof(info)); info.rti_info[RTAX_DST] = (struct sockaddr *)&sin6; info.rti_filter = nd6_isdynrte; NET_EPOCH_ENTER(et); for (fibnum = 0; fibnum < rt_numfibs; fibnum++) rib_action(fibnum, RTM_DELETE, &info, &rc); NET_EPOCH_EXIT(et); } /* * Updates status of the default router route. */ static void check_release_defrouter(struct rib_cmd_info *rc, void *_cbdata) { struct nd_defrouter *dr; struct nhop_object *nh; nh = rc->rc_nh_old; if ((nh != NULL) && (nh->nh_flags & NHF_DEFAULT)) { dr = defrouter_lookup(&nh->gw6_sa.sin6_addr, nh->nh_ifp); if (dr != NULL) { dr->installed = 0; defrouter_rele(dr); } } } void nd6_subscription_cb(struct rib_head *rnh, struct rib_cmd_info *rc, void *arg) { #ifdef ROUTE_MPATH rib_decompose_notification(rc, check_release_defrouter, NULL); #else check_release_defrouter(rc, NULL); #endif } int nd6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) { struct in6_ndireq *ndi = (struct in6_ndireq *)data; struct in6_nbrinfo *nbi = (struct in6_nbrinfo *)data; struct in6_ndifreq *ndif = (struct in6_ndifreq *)data; struct epoch_tracker et; int error = 0; if (ifp->if_afdata[AF_INET6] == NULL) return (EPFNOSUPPORT); switch (cmd) { case OSIOCGIFINFO_IN6: #define ND ndi->ndi /* XXX: old ndp(8) assumes a positive value for linkmtu. */ bzero(&ND, sizeof(ND)); ND.linkmtu = IN6_LINKMTU(ifp); ND.maxmtu = ND_IFINFO(ifp)->maxmtu; ND.basereachable = ND_IFINFO(ifp)->basereachable; ND.reachable = ND_IFINFO(ifp)->reachable; ND.retrans = ND_IFINFO(ifp)->retrans; ND.flags = ND_IFINFO(ifp)->flags; ND.recalctm = ND_IFINFO(ifp)->recalctm; ND.chlim = ND_IFINFO(ifp)->chlim; break; case SIOCGIFINFO_IN6: ND = *ND_IFINFO(ifp); break; case SIOCSIFINFO_IN6: /* * used to change host variables from userland. * intended for a use on router to reflect RA configurations. */ /* 0 means 'unspecified' */ if (ND.linkmtu != 0) { if (ND.linkmtu < IPV6_MMTU || ND.linkmtu > IN6_LINKMTU(ifp)) { error = EINVAL; break; } ND_IFINFO(ifp)->linkmtu = ND.linkmtu; } if (ND.basereachable != 0) { int obasereachable = ND_IFINFO(ifp)->basereachable; ND_IFINFO(ifp)->basereachable = ND.basereachable; if (ND.basereachable != obasereachable) ND_IFINFO(ifp)->reachable = ND_COMPUTE_RTIME(ND.basereachable); } if (ND.retrans != 0) ND_IFINFO(ifp)->retrans = ND.retrans; if (ND.chlim != 0) ND_IFINFO(ifp)->chlim = ND.chlim; /* FALLTHROUGH */ case SIOCSIFINFO_FLAGS: { struct ifaddr *ifa; struct in6_ifaddr *ia; if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && !(ND.flags & ND6_IFF_IFDISABLED)) { /* ifdisabled 1->0 transision */ /* * If the interface is marked as ND6_IFF_IFDISABLED and * has an link-local address with IN6_IFF_DUPLICATED, * do not clear ND6_IFF_IFDISABLED. * See RFC 4862, Section 5.4.5. */ NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; ia = (struct in6_ifaddr *)ifa; if ((ia->ia6_flags & IN6_IFF_DUPLICATED) && IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) break; } NET_EPOCH_EXIT(et); if (ifa != NULL) { /* LLA is duplicated. */ ND.flags |= ND6_IFF_IFDISABLED; log(LOG_ERR, "Cannot enable an interface" " with a link-local address marked" " duplicate.\n"); } else { ND_IFINFO(ifp)->flags &= ~ND6_IFF_IFDISABLED; if (ifp->if_flags & IFF_UP) in6_if_up(ifp); } } else if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && (ND.flags & ND6_IFF_IFDISABLED)) { /* ifdisabled 0->1 transision */ /* Mark all IPv6 address as tentative. */ ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; if (V_ip6_dad_count > 0 && (ND_IFINFO(ifp)->flags & ND6_IFF_NO_DAD) == 0) { NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; ia = (struct in6_ifaddr *)ifa; ia->ia6_flags |= IN6_IFF_TENTATIVE; } NET_EPOCH_EXIT(et); } } if (ND.flags & ND6_IFF_AUTO_LINKLOCAL) { if (!(ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL)) { /* auto_linklocal 0->1 transision */ /* If no link-local address on ifp, configure */ ND_IFINFO(ifp)->flags |= ND6_IFF_AUTO_LINKLOCAL; in6_ifattach(ifp, NULL); } else if (!(ND.flags & ND6_IFF_IFDISABLED) && ifp->if_flags & IFF_UP) { /* * When the IF already has * ND6_IFF_AUTO_LINKLOCAL, no link-local * address is assigned, and IFF_UP, try to * assign one. */ NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { if (ifa->ifa_addr->sa_family != AF_INET6) continue; ia = (struct in6_ifaddr *)ifa; if (IN6_IS_ADDR_LINKLOCAL(IA6_IN6(ia))) break; } NET_EPOCH_EXIT(et); if (ifa != NULL) /* No LLA is configured. */ in6_ifattach(ifp, NULL); } } ND_IFINFO(ifp)->flags = ND.flags; break; } #undef ND case SIOCSNDFLUSH_IN6: /* XXX: the ioctl name is confusing... */ /* sync kernel routing table with the default router list */ defrouter_reset(); defrouter_select_fib(RT_ALL_FIBS); break; case SIOCSPFXFLUSH_IN6: { /* flush all the prefix advertised by routers */ struct in6_ifaddr *ia, *ia_next; struct nd_prefix *pr, *next; struct nd_prhead prl; LIST_INIT(&prl); ND6_WLOCK(); LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) { if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr)) continue; /* XXX */ nd6_prefix_unlink(pr, &prl); } ND6_WUNLOCK(); while ((pr = LIST_FIRST(&prl)) != NULL) { LIST_REMOVE(pr, ndpr_entry); /* XXXRW: in6_ifaddrhead locking. */ CK_STAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link, ia_next) { if ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0) continue; if (ia->ia6_ndpr == pr) in6_purgeaddr(&ia->ia_ifa); } nd6_prefix_del(pr); } break; } case SIOCSRTRFLUSH_IN6: { /* flush all the default routers */ defrouter_reset(); nd6_defrouter_flush_all(); defrouter_select_fib(RT_ALL_FIBS); break; } case SIOCGNBRINFO_IN6: { struct llentry *ln; struct in6_addr nb_addr = nbi->addr; /* make local for safety */ if ((error = in6_setscope(&nb_addr, ifp, NULL)) != 0) return (error); NET_EPOCH_ENTER(et); ln = nd6_lookup(&nb_addr, 0, ifp); NET_EPOCH_EXIT(et); if (ln == NULL) { error = EINVAL; break; } nbi->state = ln->ln_state; nbi->asked = ln->la_asked; nbi->isrouter = ln->ln_router; if (ln->la_expire == 0) nbi->expire = 0; else nbi->expire = ln->la_expire + ln->lle_remtime / hz + (time_second - time_uptime); LLE_RUNLOCK(ln); break; } case SIOCGDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ ndif->ifindex = V_nd6_defifindex; break; case SIOCSDEFIFACE_IN6: /* XXX: should be implemented as a sysctl? */ return (nd6_setdefaultiface(ndif->ifindex)); } return (error); } /* * Calculates new isRouter value based on provided parameters and * returns it. */ static int nd6_is_router(int type, int code, int is_new, int old_addr, int new_addr, int ln_router) { /* * ICMP6 type dependent behavior. * * NS: clear IsRouter if new entry * RS: clear IsRouter * RA: set IsRouter if there's lladdr * redir: clear IsRouter if new entry * * RA case, (1): * The spec says that we must set IsRouter in the following cases: * - If lladdr exist, set IsRouter. This means (1-5). * - If it is old entry (!newentry), set IsRouter. This means (7). * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. * A quetion arises for (1) case. (1) case has no lladdr in the * neighbor cache, this is similar to (6). * This case is rare but we figured that we MUST NOT set IsRouter. * * is_new old_addr new_addr NS RS RA redir * D R * 0 n n (1) c ? s * 0 y n (2) c s s * 0 n y (3) c s s * 0 y y (4) c s s * 0 y y (5) c s s * 1 -- n (6) c c c s * 1 -- y (7) c c s c s * * (c=clear s=set) */ switch (type & 0xff) { case ND_NEIGHBOR_SOLICIT: /* * New entry must have is_router flag cleared. */ if (is_new) /* (6-7) */ ln_router = 0; break; case ND_REDIRECT: /* * If the icmp is a redirect to a better router, always set the * is_router flag. Otherwise, if the entry is newly created, * clear the flag. [RFC 2461, sec 8.3] */ if (code == ND_REDIRECT_ROUTER) ln_router = 1; else { if (is_new) /* (6-7) */ ln_router = 0; } break; case ND_ROUTER_SOLICIT: /* * is_router flag must always be cleared. */ ln_router = 0; break; case ND_ROUTER_ADVERT: /* * Mark an entry with lladdr as a router. */ if ((!is_new && (old_addr || new_addr)) || /* (2-5) */ (is_new && new_addr)) { /* (7) */ ln_router = 1; } break; } return (ln_router); } /* * Create neighbor cache entry and cache link-layer address, * on reception of inbound ND6 packets. (RS/RA/NS/redirect) * * type - ICMP6 type * code - type dependent information * */ void nd6_cache_lladdr(struct ifnet *ifp, struct in6_addr *from, char *lladdr, int lladdrlen, int type, int code) { struct llentry *ln = NULL, *ln_tmp; int is_newentry; int do_update; int olladdr; int llchange; int flags; uint16_t router = 0; struct sockaddr_in6 sin6; struct mbuf *chain = NULL; u_char linkhdr[LLE_MAX_LINKHDR]; size_t linkhdrsize; int lladdr_off; NET_EPOCH_ASSERT(); IF_AFDATA_UNLOCK_ASSERT(ifp); KASSERT(ifp != NULL, ("%s: ifp == NULL", __func__)); KASSERT(from != NULL, ("%s: from == NULL", __func__)); /* nothing must be updated for unspecified address */ if (IN6_IS_ADDR_UNSPECIFIED(from)) return; /* * Validation about ifp->if_addrlen and lladdrlen must be done in * the caller. * * XXX If the link does not have link-layer adderss, what should * we do? (ifp->if_addrlen == 0) * Spec says nothing in sections for RA, RS and NA. There's small * description on it in NS section (RFC 2461 7.2.3). */ flags = lladdr ? LLE_EXCLUSIVE : 0; ln = nd6_lookup(from, flags, ifp); is_newentry = 0; if (ln == NULL) { flags |= LLE_EXCLUSIVE; ln = nd6_alloc(from, 0, ifp); if (ln == NULL) return; /* * Since we already know all the data for the new entry, * fill it before insertion. */ if (lladdr != NULL) { linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET6, lladdr, linkhdr, &linkhdrsize, &lladdr_off) != 0) return; lltable_set_entry_addr(ifp, ln, linkhdr, linkhdrsize, lladdr_off); } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(ln); /* Prefer any existing lle over newly-created one */ ln_tmp = nd6_lookup(from, LLE_EXCLUSIVE, ifp); if (ln_tmp == NULL) lltable_link_entry(LLTABLE6(ifp), ln); IF_AFDATA_WUNLOCK(ifp); if (ln_tmp == NULL) { /* No existing lle, mark as new entry (6,7) */ is_newentry = 1; if (lladdr != NULL) { /* (7) */ nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); } } else { lltable_free_entry(LLTABLE6(ifp), ln); ln = ln_tmp; ln_tmp = NULL; } } /* do nothing if static ndp is set */ if ((ln->la_flags & LLE_STATIC)) { if (flags & LLE_EXCLUSIVE) LLE_WUNLOCK(ln); else LLE_RUNLOCK(ln); return; } olladdr = (ln->la_flags & LLE_VALID) ? 1 : 0; if (olladdr && lladdr) { llchange = bcmp(lladdr, ln->ll_addr, ifp->if_addrlen); } else if (!olladdr && lladdr) llchange = 1; else llchange = 0; /* * newentry olladdr lladdr llchange (*=record) * 0 n n -- (1) * 0 y n -- (2) * 0 n y y (3) * STALE * 0 y y n (4) * * 0 y y y (5) * STALE * 1 -- n -- (6) NOSTATE(= PASSIVE) * 1 -- y -- (7) * STALE */ do_update = 0; if (is_newentry == 0 && llchange != 0) { do_update = 1; /* (3,5) */ /* * Record source link-layer address * XXX is it dependent to ifp->if_type? */ linkhdrsize = sizeof(linkhdr); if (lltable_calc_llheader(ifp, AF_INET6, lladdr, linkhdr, &linkhdrsize, &lladdr_off) != 0) return; if (lltable_try_set_entry_addr(ifp, ln, linkhdr, linkhdrsize, lladdr_off) == 0) { /* Entry was deleted */ return; } nd6_llinfo_setstate(ln, ND6_LLINFO_STALE); EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); if (ln->la_hold != NULL) nd6_grab_holdchain(ln, &chain, &sin6); } /* Calculates new router status */ router = nd6_is_router(type, code, is_newentry, olladdr, lladdr != NULL ? 1 : 0, ln->ln_router); ln->ln_router = router; /* Mark non-router redirects with special flag */ if ((type & 0xFF) == ND_REDIRECT && code != ND_REDIRECT_ROUTER) ln->la_flags |= LLE_REDIRECT; if (flags & LLE_EXCLUSIVE) LLE_WUNLOCK(ln); else LLE_RUNLOCK(ln); if (chain != NULL) nd6_flush_holdchain(ifp, chain, &sin6); /* * When the link-layer address of a router changes, select the * best router again. In particular, when the neighbor entry is newly * created, it might affect the selection policy. * Question: can we restrict the first condition to the "is_newentry" * case? * XXX: when we hear an RA from a new router with the link-layer * address option, defrouter_select_fib() is called twice, since * defrtrlist_update called the function as well. However, I believe * we can compromise the overhead, since it only happens the first * time. * XXX: although defrouter_select_fib() should not have a bad effect * for those are not autoconfigured hosts, we explicitly avoid such * cases for safety. */ if ((do_update || is_newentry) && router && ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { /* * guaranteed recursion */ defrouter_select_fib(ifp->if_fib); } } static void nd6_slowtimo(void *arg) { struct epoch_tracker et; CURVNET_SET((struct vnet *) arg); struct nd_ifinfo *nd6if; struct ifnet *ifp; callout_reset(&V_nd6_slowtimo_ch, ND6_SLOWTIMER_INTERVAL * hz, nd6_slowtimo, curvnet); NET_EPOCH_ENTER(et); CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { if (ifp->if_afdata[AF_INET6] == NULL) continue; nd6if = ND_IFINFO(ifp); if (nd6if->basereachable && /* already initialized */ (nd6if->recalctm -= ND6_SLOWTIMER_INTERVAL) <= 0) { /* * Since reachable time rarely changes by router * advertisements, we SHOULD insure that a new random * value gets recomputed at least once every few hours. * (RFC 2461, 6.3.4) */ nd6if->recalctm = V_nd6_recalc_reachtm_interval; nd6if->reachable = ND_COMPUTE_RTIME(nd6if->basereachable); } } NET_EPOCH_EXIT(et); CURVNET_RESTORE(); } void nd6_grab_holdchain(struct llentry *ln, struct mbuf **chain, struct sockaddr_in6 *sin6) { LLE_WLOCK_ASSERT(ln); *chain = ln->la_hold; ln->la_hold = NULL; lltable_fill_sa_entry(ln, (struct sockaddr *)sin6); if (ln->ln_state == ND6_LLINFO_STALE) { /* * The first time we send a packet to a * neighbor whose entry is STALE, we have * to change the state to DELAY and a sets * a timer to expire in DELAY_FIRST_PROBE_TIME * seconds to ensure do neighbor unreachability * detection on expiration. * (RFC 2461 7.3.3) */ nd6_llinfo_setstate(ln, ND6_LLINFO_DELAY); } } int nd6_output_ifp(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m, struct sockaddr_in6 *dst, struct route *ro) { int error; int ip6len; struct ip6_hdr *ip6; struct m_tag *mtag; #ifdef MAC mac_netinet6_nd6_send(ifp, m); #endif /* * If called from nd6_ns_output() (NS), nd6_na_output() (NA), * icmp6_redirect_output() (REDIRECT) or from rip6_output() (RS, RA * as handled by rtsol and rtadvd), mbufs will be tagged for SeND * to be diverted to user space. When re-injected into the kernel, * send_output() will directly dispatch them to the outgoing interface. */ if (send_sendso_input_hook != NULL) { mtag = m_tag_find(m, PACKET_TAG_ND_OUTGOING, NULL); if (mtag != NULL) { ip6 = mtod(m, struct ip6_hdr *); ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); /* Use the SEND socket */ error = send_sendso_input_hook(m, ifp, SND_OUT, ip6len); /* -1 == no app on SEND socket */ if (error == 0 || error != -1) return (error); } } m_clrprotoflags(m); /* Avoid confusing lower layers. */ IP_PROBE(send, NULL, NULL, mtod(m, struct ip6_hdr *), ifp, NULL, mtod(m, struct ip6_hdr *)); if ((ifp->if_flags & IFF_LOOPBACK) == 0) origifp = ifp; error = (*ifp->if_output)(origifp, m, (struct sockaddr *)dst, ro); return (error); } /* * Lookup link headerfor @sa_dst address. Stores found * data in @desten buffer. Copy of lle ln_flags can be also * saved in @pflags if @pflags is non-NULL. * * If destination LLE does not exists or lle state modification * is required, call "slow" version. * * Return values: * - 0 on success (address copied to buffer). * - EWOULDBLOCK (no local error, but address is still unresolved) * - other errors (alloc failure, etc) */ int nd6_resolve(struct ifnet *ifp, int is_gw, struct mbuf *m, const struct sockaddr *sa_dst, u_char *desten, uint32_t *pflags, struct llentry **plle) { struct llentry *ln = NULL; const struct sockaddr_in6 *dst6; NET_EPOCH_ASSERT(); if (pflags != NULL) *pflags = 0; dst6 = (const struct sockaddr_in6 *)sa_dst; /* discard the packet if IPv6 operation is disabled on the interface */ if ((ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED)) { m_freem(m); return (ENETDOWN); /* better error? */ } if (m != NULL && m->m_flags & M_MCAST) { switch (ifp->if_type) { case IFT_ETHER: case IFT_L2VLAN: case IFT_BRIDGE: ETHER_MAP_IPV6_MULTICAST(&dst6->sin6_addr, desten); return (0); default: m_freem(m); return (EAFNOSUPPORT); } } ln = nd6_lookup(&dst6->sin6_addr, plle ? LLE_EXCLUSIVE : LLE_UNLOCKED, ifp); if (ln != NULL && (ln->r_flags & RLLE_VALID) != 0) { /* Entry found, let's copy lle info */ bcopy(ln->r_linkdata, desten, ln->r_hdrlen); if (pflags != NULL) *pflags = LLE_VALID | (ln->r_flags & RLLE_IFADDR); /* Check if we have feedback request from nd6 timer */ if (ln->r_skip_req != 0) { LLE_REQ_LOCK(ln); ln->r_skip_req = 0; /* Notify that entry was used */ ln->lle_hittime = time_uptime; LLE_REQ_UNLOCK(ln); } if (plle) { LLE_ADDREF(ln); *plle = ln; LLE_WUNLOCK(ln); } return (0); } else if (plle && ln) LLE_WUNLOCK(ln); return (nd6_resolve_slow(ifp, 0, m, dst6, desten, pflags, plle)); } /* * Do L2 address resolution for @sa_dst address. Stores found * address in @desten buffer. Copy of lle ln_flags can be also * saved in @pflags if @pflags is non-NULL. * * Heavy version. * Function assume that destination LLE does not exist, * is invalid or stale, so LLE_EXCLUSIVE lock needs to be acquired. * * Set noinline to be dtrace-friendly */ static __noinline int nd6_resolve_slow(struct ifnet *ifp, int flags, struct mbuf *m, const struct sockaddr_in6 *dst, u_char *desten, uint32_t *pflags, struct llentry **plle) { struct llentry *lle = NULL, *lle_tmp; struct in6_addr *psrc, src; int send_ns, ll_len; char *lladdr; NET_EPOCH_ASSERT(); /* * Address resolution or Neighbor Unreachability Detection * for the next hop. * At this point, the destination of the packet must be a unicast * or an anycast address(i.e. not a multicast). */ if (lle == NULL) { lle = nd6_lookup(&dst->sin6_addr, LLE_EXCLUSIVE, ifp); if ((lle == NULL) && nd6_is_addr_neighbor(dst, ifp)) { /* * Since nd6_is_addr_neighbor() internally calls nd6_lookup(), * the condition below is not very efficient. But we believe * it is tolerable, because this should be a rare case. */ lle = nd6_alloc(&dst->sin6_addr, 0, ifp); if (lle == NULL) { char ip6buf[INET6_ADDRSTRLEN]; log(LOG_DEBUG, "nd6_output: can't allocate llinfo for %s " "(ln=%p)\n", ip6_sprintf(ip6buf, &dst->sin6_addr), lle); m_freem(m); return (ENOBUFS); } IF_AFDATA_WLOCK(ifp); LLE_WLOCK(lle); /* Prefer any existing entry over newly-created one */ lle_tmp = nd6_lookup(&dst->sin6_addr, LLE_EXCLUSIVE, ifp); if (lle_tmp == NULL) lltable_link_entry(LLTABLE6(ifp), lle); IF_AFDATA_WUNLOCK(ifp); if (lle_tmp != NULL) { lltable_free_entry(LLTABLE6(ifp), lle); lle = lle_tmp; lle_tmp = NULL; } } } if (lle == NULL) { m_freem(m); return (ENOBUFS); } LLE_WLOCK_ASSERT(lle); /* * The first time we send a packet to a neighbor whose entry is * STALE, we have to change the state to DELAY and a sets a timer to * expire in DELAY_FIRST_PROBE_TIME seconds to ensure do * neighbor unreachability detection on expiration. * (RFC 2461 7.3.3) */ if (lle->ln_state == ND6_LLINFO_STALE) nd6_llinfo_setstate(lle, ND6_LLINFO_DELAY); /* * If the neighbor cache entry has a state other than INCOMPLETE * (i.e. its link-layer address is already resolved), just * send the packet. */ if (lle->ln_state > ND6_LLINFO_INCOMPLETE) { if (flags & LLE_ADDRONLY) { lladdr = lle->ll_addr; ll_len = ifp->if_addrlen; } else { lladdr = lle->r_linkdata; ll_len = lle->r_hdrlen; } bcopy(lladdr, desten, ll_len); if (pflags != NULL) *pflags = lle->la_flags; if (plle) { LLE_ADDREF(lle); *plle = lle; } LLE_WUNLOCK(lle); return (0); } /* * There is a neighbor cache entry, but no ethernet address * response yet. Append this latest packet to the end of the * packet queue in the mbuf. When it exceeds nd6_maxqueuelen, * the oldest packet in the queue will be removed. */ if (lle->la_hold != NULL) { struct mbuf *m_hold; int i; i = 0; for (m_hold = lle->la_hold; m_hold; m_hold = m_hold->m_nextpkt){ i++; if (m_hold->m_nextpkt == NULL) { m_hold->m_nextpkt = m; break; } } while (i >= V_nd6_maxqueuelen) { m_hold = lle->la_hold; lle->la_hold = lle->la_hold->m_nextpkt; m_freem(m_hold); i--; } } else { lle->la_hold = m; } /* * If there has been no NS for the neighbor after entering the * INCOMPLETE state, send the first solicitation. * Note that for newly-created lle la_asked will be 0, * so we will transition from ND6_LLINFO_NOSTATE to * ND6_LLINFO_INCOMPLETE state here. */ psrc = NULL; send_ns = 0; if (lle->la_asked == 0) { lle->la_asked++; send_ns = 1; psrc = nd6_llinfo_get_holdsrc(lle, &src); nd6_llinfo_setstate(lle, ND6_LLINFO_INCOMPLETE); } LLE_WUNLOCK(lle); if (send_ns != 0) nd6_ns_output(ifp, psrc, NULL, &dst->sin6_addr, NULL); return (EWOULDBLOCK); } /* * Do L2 address resolution for @sa_dst address. Stores found * address in @desten buffer. Copy of lle ln_flags can be also * saved in @pflags if @pflags is non-NULL. * * Return values: * - 0 on success (address copied to buffer). * - EWOULDBLOCK (no local error, but address is still unresolved) * - other errors (alloc failure, etc) */ int nd6_resolve_addr(struct ifnet *ifp, int flags, const struct sockaddr *dst, char *desten, uint32_t *pflags) { int error; flags |= LLE_ADDRONLY; error = nd6_resolve_slow(ifp, flags, NULL, (const struct sockaddr_in6 *)dst, desten, pflags, NULL); return (error); } int nd6_flush_holdchain(struct ifnet *ifp, struct mbuf *chain, struct sockaddr_in6 *dst) { struct mbuf *m, *m_head; int error = 0; m_head = chain; while (m_head) { m = m_head; m_head = m_head->m_nextpkt; m->m_nextpkt = NULL; error = nd6_output_ifp(ifp, ifp, m, dst, NULL); } /* * XXX * note that intermediate errors are blindly ignored */ return (error); } static int nd6_need_cache(struct ifnet *ifp) { /* * XXX: we currently do not make neighbor cache on any interface * other than Ethernet and GIF. * * RFC2893 says: * - unidirectional tunnels needs no ND */ switch (ifp->if_type) { case IFT_ETHER: case IFT_IEEE1394: case IFT_L2VLAN: case IFT_INFINIBAND: case IFT_BRIDGE: case IFT_PROPVIRTUAL: return (1); default: return (0); } } /* * Add pernament ND6 link-layer record for given * interface address. * * Very similar to IPv4 arp_ifinit(), but: * 1) IPv6 DAD is performed in different place * 2) It is called by IPv6 protocol stack in contrast to * arp_ifinit() which is typically called in SIOCSIFADDR * driver ioctl handler. * */ int nd6_add_ifa_lle(struct in6_ifaddr *ia) { struct ifnet *ifp; struct llentry *ln, *ln_tmp; struct sockaddr *dst; ifp = ia->ia_ifa.ifa_ifp; if (nd6_need_cache(ifp) == 0) return (0); dst = (struct sockaddr *)&ia->ia_addr; ln = lltable_alloc_entry(LLTABLE6(ifp), LLE_IFADDR, dst); if (ln == NULL) return (ENOBUFS); IF_AFDATA_WLOCK(ifp); LLE_WLOCK(ln); /* Unlink any entry if exists */ ln_tmp = lla_lookup(LLTABLE6(ifp), LLE_EXCLUSIVE, dst); if (ln_tmp != NULL) lltable_unlink_entry(LLTABLE6(ifp), ln_tmp); lltable_link_entry(LLTABLE6(ifp), ln); IF_AFDATA_WUNLOCK(ifp); if (ln_tmp != NULL) EVENTHANDLER_INVOKE(lle_event, ln_tmp, LLENTRY_EXPIRED); EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_RESOLVED); LLE_WUNLOCK(ln); if (ln_tmp != NULL) llentry_free(ln_tmp); return (0); } /* * Removes either all lle entries for given @ia, or lle * corresponding to @ia address. */ void nd6_rem_ifa_lle(struct in6_ifaddr *ia, int all) { struct sockaddr_in6 mask, addr; struct sockaddr *saddr, *smask; struct ifnet *ifp; ifp = ia->ia_ifa.ifa_ifp; memcpy(&addr, &ia->ia_addr, sizeof(ia->ia_addr)); memcpy(&mask, &ia->ia_prefixmask, sizeof(ia->ia_prefixmask)); saddr = (struct sockaddr *)&addr; smask = (struct sockaddr *)&mask; if (all != 0) lltable_prefix_free(AF_INET6, saddr, smask, LLE_STATIC); else lltable_delete_addr(LLTABLE6(ifp), LLE_IFADDR, saddr); } static void clear_llinfo_pqueue(struct llentry *ln) { struct mbuf *m_hold, *m_hold_next; for (m_hold = ln->la_hold; m_hold; m_hold = m_hold_next) { m_hold_next = m_hold->m_nextpkt; m_freem(m_hold); } ln->la_hold = NULL; } static int nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS) { struct in6_prefix p; struct sockaddr_in6 s6; struct nd_prefix *pr; struct nd_pfxrouter *pfr; time_t maxexpire; int error; char ip6buf[INET6_ADDRSTRLEN]; if (req->newptr) return (EPERM); error = sysctl_wire_old_buffer(req, 0); if (error != 0) return (error); bzero(&p, sizeof(p)); p.origin = PR_ORIG_RA; bzero(&s6, sizeof(s6)); s6.sin6_family = AF_INET6; s6.sin6_len = sizeof(s6); ND6_RLOCK(); LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) { p.prefix = pr->ndpr_prefix; if (sa6_recoverscope(&p.prefix)) { log(LOG_ERR, "scope error in prefix list (%s)\n", ip6_sprintf(ip6buf, &p.prefix.sin6_addr)); /* XXX: press on... */ } p.raflags = pr->ndpr_raf; p.prefixlen = pr->ndpr_plen; p.vltime = pr->ndpr_vltime; p.pltime = pr->ndpr_pltime; p.if_index = pr->ndpr_ifp->if_index; if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME) p.expire = 0; else { /* XXX: we assume time_t is signed. */ maxexpire = (-1) & ~((time_t)1 << ((sizeof(maxexpire) * 8) - 1)); if (pr->ndpr_vltime < maxexpire - pr->ndpr_lastupdate) p.expire = pr->ndpr_lastupdate + pr->ndpr_vltime + (time_second - time_uptime); else p.expire = maxexpire; } p.refcnt = pr->ndpr_addrcnt; p.flags = pr->ndpr_stateflags; p.advrtrs = 0; LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) p.advrtrs++; error = SYSCTL_OUT(req, &p, sizeof(p)); if (error != 0) break; LIST_FOREACH(pfr, &pr->ndpr_advrtrs, pfr_entry) { s6.sin6_addr = pfr->router->rtaddr; if (sa6_recoverscope(&s6)) log(LOG_ERR, "scope error in prefix list (%s)\n", ip6_sprintf(ip6buf, &pfr->router->rtaddr)); error = SYSCTL_OUT(req, &s6, sizeof(s6)); if (error != 0) goto out; } } out: ND6_RUNLOCK(); return (error); } SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ND6_PRLIST, nd6_prlist, CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, nd6_sysctl_prlist, "S,in6_prefix", "NDP prefix list"); SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXQLEN, nd6_maxqueuelen, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_maxqueuelen), 1, ""); SYSCTL_INT(_net_inet6_icmp6, OID_AUTO, nd6_gctimer, CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(nd6_gctimer), (60 * 60 * 24), "");