The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/netinet/ip_carp.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 2002 Michael Shalayeff.
    3  * Copyright (c) 2003 Ryan McBride.
    4  * Copyright (c) 2011 Gleb Smirnoff <glebius@FreeBSD.org>
    5  * All rights reserved.
    6  *
    7  * Redistribution and use in source and binary forms, with or without
    8  * modification, are permitted provided that the following conditions
    9  * are met:
   10  * 1. Redistributions of source code must retain the above copyright
   11  *    notice, this list of conditions and the following disclaimer.
   12  * 2. Redistributions in binary form must reproduce the above copyright
   13  *    notice, this list of conditions and the following disclaimer in the
   14  *    documentation and/or other materials provided with the distribution.
   15  *
   16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   19  * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
   20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   22  * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
   25  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   26  * THE POSSIBILITY OF SUCH DAMAGE.
   27  */
   28 
   29 #include <sys/cdefs.h>
   30 __FBSDID("$FreeBSD: releng/11.1/sys/netinet/ip_carp.c 312445 2017-01-20 00:17:53Z jpaetzel $");
   31 
   32 #include "opt_bpf.h"
   33 #include "opt_inet.h"
   34 #include "opt_inet6.h"
   35 
   36 #include <sys/param.h>
   37 #include <sys/systm.h>
   38 #include <sys/bus.h>
   39 #include <sys/jail.h>
   40 #include <sys/kernel.h>
   41 #include <sys/limits.h>
   42 #include <sys/malloc.h>
   43 #include <sys/mbuf.h>
   44 #include <sys/module.h>
   45 #include <sys/priv.h>
   46 #include <sys/proc.h>
   47 #include <sys/protosw.h>
   48 #include <sys/socket.h>
   49 #include <sys/sockio.h>
   50 #include <sys/sysctl.h>
   51 #include <sys/syslog.h>
   52 #include <sys/taskqueue.h>
   53 #include <sys/counter.h>
   54 
   55 #include <net/ethernet.h>
   56 #include <net/fddi.h>
   57 #include <net/if.h>
   58 #include <net/if_var.h>
   59 #include <net/if_dl.h>
   60 #include <net/if_llatbl.h>
   61 #include <net/if_types.h>
   62 #include <net/iso88025.h>
   63 #include <net/route.h>
   64 #include <net/vnet.h>
   65 
   66 #if defined(INET) || defined(INET6)
   67 #include <netinet/in.h>
   68 #include <netinet/in_var.h>
   69 #include <netinet/ip_carp.h>
   70 #include <netinet/ip.h>
   71 #include <machine/in_cksum.h>
   72 #endif
   73 #ifdef INET
   74 #include <netinet/ip_var.h>
   75 #include <netinet/if_ether.h>
   76 #endif
   77 
   78 #ifdef INET6
   79 #include <netinet/icmp6.h>
   80 #include <netinet/ip6.h>
   81 #include <netinet6/in6_var.h>
   82 #include <netinet6/ip6_var.h>
   83 #include <netinet6/scope6_var.h>
   84 #include <netinet6/nd6.h>
   85 #endif
   86 
   87 #include <crypto/sha1.h>
   88 
   89 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses");
   90 
   91 struct carp_softc {
   92         struct ifnet            *sc_carpdev;    /* Pointer to parent ifnet. */
   93         struct ifaddr           **sc_ifas;      /* Our ifaddrs. */
   94         struct sockaddr_dl      sc_addr;        /* Our link level address. */
   95         struct callout          sc_ad_tmo;      /* Advertising timeout. */
   96 #ifdef INET
   97         struct callout          sc_md_tmo;      /* Master down timeout. */
   98 #endif
   99 #ifdef INET6
  100         struct callout          sc_md6_tmo;     /* XXX: Master down timeout. */
  101 #endif
  102         struct mtx              sc_mtx;
  103 
  104         int                     sc_vhid;
  105         int                     sc_advskew;
  106         int                     sc_advbase;
  107 
  108         int                     sc_naddrs;
  109         int                     sc_naddrs6;
  110         int                     sc_ifasiz;
  111         enum { INIT = 0, BACKUP, MASTER }       sc_state;
  112         int                     sc_suppress;
  113         int                     sc_sendad_errors;
  114 #define CARP_SENDAD_MAX_ERRORS  3
  115         int                     sc_sendad_success;
  116 #define CARP_SENDAD_MIN_SUCCESS 3
  117 
  118         int                     sc_init_counter;
  119         uint64_t                sc_counter;
  120 
  121         /* authentication */
  122 #define CARP_HMAC_PAD   64
  123         unsigned char sc_key[CARP_KEY_LEN];
  124         unsigned char sc_pad[CARP_HMAC_PAD];
  125         SHA1_CTX sc_sha1;
  126 
  127         TAILQ_ENTRY(carp_softc) sc_list;        /* On the carp_if list. */
  128         LIST_ENTRY(carp_softc)  sc_next;        /* On the global list. */
  129 };
  130 
  131 struct carp_if {
  132 #ifdef INET
  133         int     cif_naddrs;
  134 #endif
  135 #ifdef INET6
  136         int     cif_naddrs6;
  137 #endif
  138         TAILQ_HEAD(, carp_softc) cif_vrs;
  139 #ifdef INET
  140         struct ip_moptions       cif_imo;
  141 #endif
  142 #ifdef INET6
  143         struct ip6_moptions      cif_im6o;
  144 #endif
  145         struct ifnet    *cif_ifp;
  146         struct mtx      cif_mtx;
  147         uint32_t        cif_flags;
  148 #define CIF_PROMISC     0x00000001
  149 };
  150 
  151 #define CARP_INET       0
  152 #define CARP_INET6      1
  153 static int proto_reg[] = {-1, -1};
  154 
  155 /*
  156  * Brief design of carp(4).
  157  *
  158  * Any carp-capable ifnet may have a list of carp softcs hanging off
  159  * its ifp->if_carp pointer. Each softc represents one unique virtual
  160  * host id, or vhid. The softc has a back pointer to the ifnet. All
  161  * softcs are joined in a global list, which has quite limited use.
  162  *
  163  * Any interface address that takes part in CARP negotiation has a
  164  * pointer to the softc of its vhid, ifa->ifa_carp. That could be either
  165  * AF_INET or AF_INET6 address.
  166  *
  167  * Although, one can get the softc's backpointer to ifnet and traverse
  168  * through its ifp->if_addrhead queue to find all interface addresses
  169  * involved in CARP, we keep a growable array of ifaddr pointers. This
  170  * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that
  171  * do calls into the network stack, thus avoiding LORs.
  172  *
  173  * Locking:
  174  *
  175  * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(),
  176  * callout-driven events and ioctl()s.
  177  *
  178  * To traverse the list of softcs on an ifnet we use CIF_LOCK(), to
  179  * traverse the global list we use the mutex carp_mtx.
  180  *
  181  * Known issues with locking:
  182  *
  183  * - Sending ad, we put the pointer to the softc in an mtag, and no reference
  184  *   counting is done on the softc.
  185  * - On module unload we may race (?) with packet processing thread
  186  *   dereferencing our function pointers.
  187  */
  188 
  189 /* Accept incoming CARP packets. */
  190 static VNET_DEFINE(int, carp_allow) = 1;
  191 #define V_carp_allow    VNET(carp_allow)
  192 
  193 /* Preempt slower nodes. */
  194 static VNET_DEFINE(int, carp_preempt) = 0;
  195 #define V_carp_preempt  VNET(carp_preempt)
  196 
  197 /* Log level. */
  198 static VNET_DEFINE(int, carp_log) = 1;
  199 #define V_carp_log      VNET(carp_log)
  200 
  201 /* Global advskew demotion. */
  202 static VNET_DEFINE(int, carp_demotion) = 0;
  203 #define V_carp_demotion VNET(carp_demotion)
  204 
  205 /* Send error demotion factor. */
  206 static VNET_DEFINE(int, carp_senderr_adj) = CARP_MAXSKEW;
  207 #define V_carp_senderr_adj      VNET(carp_senderr_adj)
  208 
  209 /* Iface down demotion factor. */
  210 static VNET_DEFINE(int, carp_ifdown_adj) = CARP_MAXSKEW;
  211 #define V_carp_ifdown_adj       VNET(carp_ifdown_adj)
  212 
  213 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS);
  214 
  215 SYSCTL_NODE(_net_inet, IPPROTO_CARP,    carp,   CTLFLAG_RW, 0,  "CARP");
  216 SYSCTL_INT(_net_inet_carp, OID_AUTO, allow, CTLFLAG_VNET | CTLFLAG_RW,
  217     &VNET_NAME(carp_allow), 0, "Accept incoming CARP packets");
  218 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW,
  219     &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode");
  220 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW,
  221     &VNET_NAME(carp_log), 0, "CARP log level");
  222 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion,
  223     CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW,
  224     0, 0, carp_demote_adj_sysctl, "I",
  225     "Adjust demotion factor (skew of advskew)");
  226 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor,
  227     CTLFLAG_VNET | CTLFLAG_RW,
  228     &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment");
  229 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor,
  230     CTLFLAG_VNET | CTLFLAG_RW,
  231     &VNET_NAME(carp_ifdown_adj), 0,
  232     "Interface down demotion factor adjustment");
  233 
  234 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats);
  235 VNET_PCPUSTAT_SYSINIT(carpstats);
  236 VNET_PCPUSTAT_SYSUNINIT(carpstats);
  237 
  238 #define CARPSTATS_ADD(name, val)        \
  239     counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \
  240         sizeof(uint64_t)], (val))
  241 #define CARPSTATS_INC(name)             CARPSTATS_ADD(name, 1)
  242 
  243 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats,
  244     carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)");
  245 
  246 #define CARP_LOCK_INIT(sc)      mtx_init(&(sc)->sc_mtx, "carp_softc",   \
  247         NULL, MTX_DEF)
  248 #define CARP_LOCK_DESTROY(sc)   mtx_destroy(&(sc)->sc_mtx)
  249 #define CARP_LOCK_ASSERT(sc)    mtx_assert(&(sc)->sc_mtx, MA_OWNED)
  250 #define CARP_LOCK(sc)           mtx_lock(&(sc)->sc_mtx)
  251 #define CARP_UNLOCK(sc)         mtx_unlock(&(sc)->sc_mtx)
  252 #define CIF_LOCK_INIT(cif)      mtx_init(&(cif)->cif_mtx, "carp_if",   \
  253         NULL, MTX_DEF)
  254 #define CIF_LOCK_DESTROY(cif)   mtx_destroy(&(cif)->cif_mtx)
  255 #define CIF_LOCK_ASSERT(cif)    mtx_assert(&(cif)->cif_mtx, MA_OWNED)
  256 #define CIF_LOCK(cif)           mtx_lock(&(cif)->cif_mtx)
  257 #define CIF_UNLOCK(cif)         mtx_unlock(&(cif)->cif_mtx)
  258 #define CIF_FREE(cif)   do {                            \
  259                 CIF_LOCK(cif);                          \
  260                 if (TAILQ_EMPTY(&(cif)->cif_vrs))       \
  261                         carp_free_if(cif);              \
  262                 else                                    \
  263                         CIF_UNLOCK(cif);                \
  264 } while (0)
  265 
  266 #define CARP_LOG(...)   do {                            \
  267         if (V_carp_log > 0)                             \
  268                 log(LOG_INFO, "carp: " __VA_ARGS__);    \
  269 } while (0)
  270 
  271 #define CARP_DEBUG(...) do {                            \
  272         if (V_carp_log > 1)                             \
  273                 log(LOG_DEBUG, __VA_ARGS__);            \
  274 } while (0)
  275 
  276 #define IFNET_FOREACH_IFA(ifp, ifa)                                     \
  277         IF_ADDR_LOCK_ASSERT(ifp);                                       \
  278         TAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link)             \
  279                 if ((ifa)->ifa_carp != NULL)
  280 
  281 #define CARP_FOREACH_IFA(sc, ifa)                                       \
  282         CARP_LOCK_ASSERT(sc);                                           \
  283         for (int _i = 0;                                                \
  284                 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 &&              \
  285                 ((ifa) = sc->sc_ifas[_i]) != NULL;                      \
  286                 ++_i)
  287 
  288 #define IFNET_FOREACH_CARP(ifp, sc)                                     \
  289         CIF_LOCK_ASSERT(ifp->if_carp);                                  \
  290         TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list)
  291 
  292 #define DEMOTE_ADVSKEW(sc)                                      \
  293     (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ?      \
  294     CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion))
  295 
  296 static void     carp_input_c(struct mbuf *, struct carp_header *, sa_family_t);
  297 static struct carp_softc
  298                 *carp_alloc(struct ifnet *);
  299 static void     carp_destroy(struct carp_softc *);
  300 static struct carp_if
  301                 *carp_alloc_if(struct ifnet *);
  302 static void     carp_free_if(struct carp_if *);
  303 static void     carp_set_state(struct carp_softc *, int, const char* reason);
  304 static void     carp_sc_state(struct carp_softc *);
  305 static void     carp_setrun(struct carp_softc *, sa_family_t);
  306 static void     carp_master_down(void *);
  307 static void     carp_master_down_locked(struct carp_softc *,
  308                     const char* reason);
  309 static void     carp_send_ad(void *);
  310 static void     carp_send_ad_locked(struct carp_softc *);
  311 static void     carp_addroute(struct carp_softc *);
  312 static void     carp_ifa_addroute(struct ifaddr *);
  313 static void     carp_delroute(struct carp_softc *);
  314 static void     carp_ifa_delroute(struct ifaddr *);
  315 static void     carp_send_ad_all(void *, int);
  316 static void     carp_demote_adj(int, char *);
  317 
  318 static LIST_HEAD(, carp_softc) carp_list;
  319 static struct mtx carp_mtx;
  320 static struct sx carp_sx;
  321 static struct task carp_sendall_task =
  322     TASK_INITIALIZER(0, carp_send_ad_all, NULL);
  323 
  324 static void
  325 carp_hmac_prepare(struct carp_softc *sc)
  326 {
  327         uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
  328         uint8_t vhid = sc->sc_vhid & 0xff;
  329         struct ifaddr *ifa;
  330         int i, found;
  331 #ifdef INET
  332         struct in_addr last, cur, in;
  333 #endif
  334 #ifdef INET6
  335         struct in6_addr last6, cur6, in6;
  336 #endif
  337 
  338         CARP_LOCK_ASSERT(sc);
  339 
  340         /* Compute ipad from key. */
  341         bzero(sc->sc_pad, sizeof(sc->sc_pad));
  342         bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key));
  343         for (i = 0; i < sizeof(sc->sc_pad); i++)
  344                 sc->sc_pad[i] ^= 0x36;
  345 
  346         /* Precompute first part of inner hash. */
  347         SHA1Init(&sc->sc_sha1);
  348         SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
  349         SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version));
  350         SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
  351         SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
  352 #ifdef INET
  353         cur.s_addr = 0;
  354         do {
  355                 found = 0;
  356                 last = cur;
  357                 cur.s_addr = 0xffffffff;
  358                 CARP_FOREACH_IFA(sc, ifa) {
  359                         in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr;
  360                         if (ifa->ifa_addr->sa_family == AF_INET &&
  361                             ntohl(in.s_addr) > ntohl(last.s_addr) &&
  362                             ntohl(in.s_addr) < ntohl(cur.s_addr)) {
  363                                 cur.s_addr = in.s_addr;
  364                                 found++;
  365                         }
  366                 }
  367                 if (found)
  368                         SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur));
  369         } while (found);
  370 #endif /* INET */
  371 #ifdef INET6
  372         memset(&cur6, 0, sizeof(cur6));
  373         do {
  374                 found = 0;
  375                 last6 = cur6;
  376                 memset(&cur6, 0xff, sizeof(cur6));
  377                 CARP_FOREACH_IFA(sc, ifa) {
  378                         in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
  379                         if (IN6_IS_SCOPE_EMBED(&in6))
  380                                 in6.s6_addr16[1] = 0;
  381                         if (ifa->ifa_addr->sa_family == AF_INET6 &&
  382                             memcmp(&in6, &last6, sizeof(in6)) > 0 &&
  383                             memcmp(&in6, &cur6, sizeof(in6)) < 0) {
  384                                 cur6 = in6;
  385                                 found++;
  386                         }
  387                 }
  388                 if (found)
  389                         SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6));
  390         } while (found);
  391 #endif /* INET6 */
  392 
  393         /* convert ipad to opad */
  394         for (i = 0; i < sizeof(sc->sc_pad); i++)
  395                 sc->sc_pad[i] ^= 0x36 ^ 0x5c;
  396 }
  397 
  398 static void
  399 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2],
  400     unsigned char md[20])
  401 {
  402         SHA1_CTX sha1ctx;
  403 
  404         CARP_LOCK_ASSERT(sc);
  405 
  406         /* fetch first half of inner hash */
  407         bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx));
  408 
  409         SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
  410         SHA1Final(md, &sha1ctx);
  411 
  412         /* outer hash */
  413         SHA1Init(&sha1ctx);
  414         SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
  415         SHA1Update(&sha1ctx, md, 20);
  416         SHA1Final(md, &sha1ctx);
  417 }
  418 
  419 static int
  420 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2],
  421     unsigned char md[20])
  422 {
  423         unsigned char md2[20];
  424 
  425         CARP_LOCK_ASSERT(sc);
  426 
  427         carp_hmac_generate(sc, counter, md2);
  428 
  429         return (bcmp(md, md2, sizeof(md2)));
  430 }
  431 
  432 /*
  433  * process input packet.
  434  * we have rearranged checks order compared to the rfc,
  435  * but it seems more efficient this way or not possible otherwise.
  436  */
  437 #ifdef INET
  438 int
  439 carp_input(struct mbuf **mp, int *offp, int proto)
  440 {
  441         struct mbuf *m = *mp;
  442         struct ip *ip = mtod(m, struct ip *);
  443         struct carp_header *ch;
  444         int iplen, len;
  445 
  446         iplen = *offp;
  447         *mp = NULL;
  448 
  449         CARPSTATS_INC(carps_ipackets);
  450 
  451         if (!V_carp_allow) {
  452                 m_freem(m);
  453                 return (IPPROTO_DONE);
  454         }
  455 
  456         /* verify that the IP TTL is 255.  */
  457         if (ip->ip_ttl != CARP_DFLTTL) {
  458                 CARPSTATS_INC(carps_badttl);
  459                 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
  460                     ip->ip_ttl,
  461                     m->m_pkthdr.rcvif->if_xname);
  462                 m_freem(m);
  463                 return (IPPROTO_DONE);
  464         }
  465 
  466         iplen = ip->ip_hl << 2;
  467 
  468         if (m->m_pkthdr.len < iplen + sizeof(*ch)) {
  469                 CARPSTATS_INC(carps_badlen);
  470                 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) "
  471                     "on %s\n", __func__, m->m_len - sizeof(struct ip),
  472                     m->m_pkthdr.rcvif->if_xname);
  473                 m_freem(m);
  474                 return (IPPROTO_DONE);
  475         }
  476 
  477         if (iplen + sizeof(*ch) < m->m_len) {
  478                 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) {
  479                         CARPSTATS_INC(carps_hdrops);
  480                         CARP_DEBUG("%s: pullup failed\n", __func__);
  481                         return (IPPROTO_DONE);
  482                 }
  483                 ip = mtod(m, struct ip *);
  484         }
  485         ch = (struct carp_header *)((char *)ip + iplen);
  486 
  487         /*
  488          * verify that the received packet length is
  489          * equal to the CARP header
  490          */
  491         len = iplen + sizeof(*ch);
  492         if (len > m->m_pkthdr.len) {
  493                 CARPSTATS_INC(carps_badlen);
  494                 CARP_DEBUG("%s: packet too short %d on %s\n", __func__,
  495                     m->m_pkthdr.len,
  496                     m->m_pkthdr.rcvif->if_xname);
  497                 m_freem(m);
  498                 return (IPPROTO_DONE);
  499         }
  500 
  501         if ((m = m_pullup(m, len)) == NULL) {
  502                 CARPSTATS_INC(carps_hdrops);
  503                 return (IPPROTO_DONE);
  504         }
  505         ip = mtod(m, struct ip *);
  506         ch = (struct carp_header *)((char *)ip + iplen);
  507 
  508         /* verify the CARP checksum */
  509         m->m_data += iplen;
  510         if (in_cksum(m, len - iplen)) {
  511                 CARPSTATS_INC(carps_badsum);
  512                 CARP_DEBUG("%s: checksum failed on %s\n", __func__,
  513                     m->m_pkthdr.rcvif->if_xname);
  514                 m_freem(m);
  515                 return (IPPROTO_DONE);
  516         }
  517         m->m_data -= iplen;
  518 
  519         carp_input_c(m, ch, AF_INET);
  520         return (IPPROTO_DONE);
  521 }
  522 #endif
  523 
  524 #ifdef INET6
  525 int
  526 carp6_input(struct mbuf **mp, int *offp, int proto)
  527 {
  528         struct mbuf *m = *mp;
  529         struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
  530         struct carp_header *ch;
  531         u_int len;
  532 
  533         CARPSTATS_INC(carps_ipackets6);
  534 
  535         if (!V_carp_allow) {
  536                 m_freem(m);
  537                 return (IPPROTO_DONE);
  538         }
  539 
  540         /* check if received on a valid carp interface */
  541         if (m->m_pkthdr.rcvif->if_carp == NULL) {
  542                 CARPSTATS_INC(carps_badif);
  543                 CARP_DEBUG("%s: packet received on non-carp interface: %s\n",
  544                     __func__, m->m_pkthdr.rcvif->if_xname);
  545                 m_freem(m);
  546                 return (IPPROTO_DONE);
  547         }
  548 
  549         /* verify that the IP TTL is 255 */
  550         if (ip6->ip6_hlim != CARP_DFLTTL) {
  551                 CARPSTATS_INC(carps_badttl);
  552                 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
  553                     ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname);
  554                 m_freem(m);
  555                 return (IPPROTO_DONE);
  556         }
  557 
  558         /* verify that we have a complete carp packet */
  559         len = m->m_len;
  560         IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch));
  561         if (ch == NULL) {
  562                 CARPSTATS_INC(carps_badlen);
  563                 CARP_DEBUG("%s: packet size %u too small\n", __func__, len);
  564                 return (IPPROTO_DONE);
  565         }
  566 
  567 
  568         /* verify the CARP checksum */
  569         m->m_data += *offp;
  570         if (in_cksum(m, sizeof(*ch))) {
  571                 CARPSTATS_INC(carps_badsum);
  572                 CARP_DEBUG("%s: checksum failed, on %s\n", __func__,
  573                     m->m_pkthdr.rcvif->if_xname);
  574                 m_freem(m);
  575                 return (IPPROTO_DONE);
  576         }
  577         m->m_data -= *offp;
  578 
  579         carp_input_c(m, ch, AF_INET6);
  580         return (IPPROTO_DONE);
  581 }
  582 #endif /* INET6 */
  583 
  584 static void
  585 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
  586 {
  587         struct ifnet *ifp = m->m_pkthdr.rcvif;
  588         struct ifaddr *ifa;
  589         struct carp_softc *sc;
  590         uint64_t tmp_counter;
  591         struct timeval sc_tv, ch_tv;
  592 
  593         /* verify that the VHID is valid on the receiving interface */
  594         IF_ADDR_RLOCK(ifp);
  595         IFNET_FOREACH_IFA(ifp, ifa)
  596                 if (ifa->ifa_addr->sa_family == af &&
  597                     ifa->ifa_carp->sc_vhid == ch->carp_vhid) {
  598                         ifa_ref(ifa);
  599                         break;
  600                 }
  601         IF_ADDR_RUNLOCK(ifp);
  602 
  603         if (ifa == NULL) {
  604                 CARPSTATS_INC(carps_badvhid);
  605                 m_freem(m);
  606                 return;
  607         }
  608 
  609         /* verify the CARP version. */
  610         if (ch->carp_version != CARP_VERSION) {
  611                 CARPSTATS_INC(carps_badver);
  612                 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname,
  613                     ch->carp_version);
  614                 ifa_free(ifa);
  615                 m_freem(m);
  616                 return;
  617         }
  618 
  619         sc = ifa->ifa_carp;
  620         CARP_LOCK(sc);
  621         ifa_free(ifa);
  622 
  623         if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
  624                 CARPSTATS_INC(carps_badauth);
  625                 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__,
  626                     sc->sc_vhid, ifp->if_xname);
  627                 goto out;
  628         }
  629 
  630         tmp_counter = ntohl(ch->carp_counter[0]);
  631         tmp_counter = tmp_counter<<32;
  632         tmp_counter += ntohl(ch->carp_counter[1]);
  633 
  634         /* XXX Replay protection goes here */
  635 
  636         sc->sc_init_counter = 0;
  637         sc->sc_counter = tmp_counter;
  638 
  639         sc_tv.tv_sec = sc->sc_advbase;
  640         sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256;
  641         ch_tv.tv_sec = ch->carp_advbase;
  642         ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
  643 
  644         switch (sc->sc_state) {
  645         case INIT:
  646                 break;
  647         case MASTER:
  648                 /*
  649                  * If we receive an advertisement from a master who's going to
  650                  * be more frequent than us, go into BACKUP state.
  651                  */
  652                 if (timevalcmp(&sc_tv, &ch_tv, >) ||
  653                     timevalcmp(&sc_tv, &ch_tv, ==)) {
  654                         callout_stop(&sc->sc_ad_tmo);
  655                         carp_set_state(sc, BACKUP,
  656                             "more frequent advertisement received");
  657                         carp_setrun(sc, 0);
  658                         carp_delroute(sc);
  659                 }
  660                 break;
  661         case BACKUP:
  662                 /*
  663                  * If we're pre-empting masters who advertise slower than us,
  664                  * and this one claims to be slower, treat him as down.
  665                  */
  666                 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) {
  667                         carp_master_down_locked(sc,
  668                             "preempting a slower master");
  669                         break;
  670                 }
  671 
  672                 /*
  673                  *  If the master is going to advertise at such a low frequency
  674                  *  that he's guaranteed to time out, we'd might as well just
  675                  *  treat him as timed out now.
  676                  */
  677                 sc_tv.tv_sec = sc->sc_advbase * 3;
  678                 if (timevalcmp(&sc_tv, &ch_tv, <)) {
  679                         carp_master_down_locked(sc, "master will time out");
  680                         break;
  681                 }
  682 
  683                 /*
  684                  * Otherwise, we reset the counter and wait for the next
  685                  * advertisement.
  686                  */
  687                 carp_setrun(sc, af);
  688                 break;
  689         }
  690 
  691 out:
  692         CARP_UNLOCK(sc);
  693         m_freem(m);
  694 }
  695 
  696 static int
  697 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch)
  698 {
  699         struct m_tag *mtag;
  700 
  701         if (sc->sc_init_counter) {
  702                 /* this could also be seconds since unix epoch */
  703                 sc->sc_counter = arc4random();
  704                 sc->sc_counter = sc->sc_counter << 32;
  705                 sc->sc_counter += arc4random();
  706         } else
  707                 sc->sc_counter++;
  708 
  709         ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
  710         ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
  711 
  712         carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
  713 
  714         /* Tag packet for carp_output */
  715         if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *),
  716             M_NOWAIT)) == NULL) {
  717                 m_freem(m);
  718                 CARPSTATS_INC(carps_onomem);
  719                 return (ENOMEM);
  720         }
  721         bcopy(&sc, mtag + 1, sizeof(sc));
  722         m_tag_prepend(m, mtag);
  723 
  724         return (0);
  725 }
  726 
  727 /*
  728  * To avoid LORs and possible recursions this function shouldn't
  729  * be called directly, but scheduled via taskqueue.
  730  */
  731 static void
  732 carp_send_ad_all(void *ctx __unused, int pending __unused)
  733 {
  734         struct carp_softc *sc;
  735 
  736         mtx_lock(&carp_mtx);
  737         LIST_FOREACH(sc, &carp_list, sc_next)
  738                 if (sc->sc_state == MASTER) {
  739                         CARP_LOCK(sc);
  740                         CURVNET_SET(sc->sc_carpdev->if_vnet);
  741                         carp_send_ad_locked(sc);
  742                         CURVNET_RESTORE();
  743                         CARP_UNLOCK(sc);
  744                 }
  745         mtx_unlock(&carp_mtx);
  746 }
  747 
  748 /* Send a periodic advertisement, executed in callout context. */
  749 static void
  750 carp_send_ad(void *v)
  751 {
  752         struct carp_softc *sc = v;
  753 
  754         CARP_LOCK_ASSERT(sc);
  755         CURVNET_SET(sc->sc_carpdev->if_vnet);
  756         carp_send_ad_locked(sc);
  757         CURVNET_RESTORE();
  758         CARP_UNLOCK(sc);
  759 }
  760 
  761 static void
  762 carp_send_ad_error(struct carp_softc *sc, int error)
  763 {
  764 
  765         if (error) {
  766                 if (sc->sc_sendad_errors < INT_MAX)
  767                         sc->sc_sendad_errors++;
  768                 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
  769                         static const char fmt[] = "send error %d on %s";
  770                         char msg[sizeof(fmt) + IFNAMSIZ];
  771 
  772                         sprintf(msg, fmt, error, sc->sc_carpdev->if_xname);
  773                         carp_demote_adj(V_carp_senderr_adj, msg);
  774                 }
  775                 sc->sc_sendad_success = 0;
  776         } else {
  777                 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS &&
  778                     ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) {
  779                         static const char fmt[] = "send ok on %s";
  780                         char msg[sizeof(fmt) + IFNAMSIZ];
  781 
  782                         sprintf(msg, fmt, sc->sc_carpdev->if_xname);
  783                         carp_demote_adj(-V_carp_senderr_adj, msg);
  784                         sc->sc_sendad_errors = 0;
  785                 } else
  786                         sc->sc_sendad_errors = 0;
  787         }
  788 }
  789 
  790 static void
  791 carp_send_ad_locked(struct carp_softc *sc)
  792 {
  793         struct carp_header ch;
  794         struct timeval tv;
  795         struct sockaddr sa;
  796         struct ifaddr *ifa;
  797         struct carp_header *ch_ptr;
  798         struct mbuf *m;
  799         int len, advskew;
  800 
  801         CARP_LOCK_ASSERT(sc);
  802 
  803         advskew = DEMOTE_ADVSKEW(sc);
  804         tv.tv_sec = sc->sc_advbase;
  805         tv.tv_usec = advskew * 1000000 / 256;
  806 
  807         ch.carp_version = CARP_VERSION;
  808         ch.carp_type = CARP_ADVERTISEMENT;
  809         ch.carp_vhid = sc->sc_vhid;
  810         ch.carp_advbase = sc->sc_advbase;
  811         ch.carp_advskew = advskew;
  812         ch.carp_authlen = 7;    /* XXX DEFINE */
  813         ch.carp_pad1 = 0;       /* must be zero */
  814         ch.carp_cksum = 0;
  815 
  816         /* XXXGL: OpenBSD picks first ifaddr with needed family. */
  817 
  818 #ifdef INET
  819         if (sc->sc_naddrs) {
  820                 struct ip *ip;
  821 
  822                 m = m_gethdr(M_NOWAIT, MT_DATA);
  823                 if (m == NULL) {
  824                         CARPSTATS_INC(carps_onomem);
  825                         goto resched;
  826                 }
  827                 len = sizeof(*ip) + sizeof(ch);
  828                 m->m_pkthdr.len = len;
  829                 m->m_pkthdr.rcvif = NULL;
  830                 m->m_len = len;
  831                 M_ALIGN(m, m->m_len);
  832                 m->m_flags |= M_MCAST;
  833                 ip = mtod(m, struct ip *);
  834                 ip->ip_v = IPVERSION;
  835                 ip->ip_hl = sizeof(*ip) >> 2;
  836                 ip->ip_tos = IPTOS_LOWDELAY;
  837                 ip->ip_len = htons(len);
  838                 ip->ip_off = htons(IP_DF);
  839                 ip->ip_ttl = CARP_DFLTTL;
  840                 ip->ip_p = IPPROTO_CARP;
  841                 ip->ip_sum = 0;
  842                 ip_fillid(ip);
  843 
  844                 bzero(&sa, sizeof(sa));
  845                 sa.sa_family = AF_INET;
  846                 ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
  847                 if (ifa != NULL) {
  848                         ip->ip_src.s_addr =
  849                             ifatoia(ifa)->ia_addr.sin_addr.s_addr;
  850                         ifa_free(ifa);
  851                 } else
  852                         ip->ip_src.s_addr = 0;
  853                 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP);
  854 
  855                 ch_ptr = (struct carp_header *)(&ip[1]);
  856                 bcopy(&ch, ch_ptr, sizeof(ch));
  857                 if (carp_prepare_ad(m, sc, ch_ptr))
  858                         goto resched;
  859 
  860                 m->m_data += sizeof(*ip);
  861                 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip));
  862                 m->m_data -= sizeof(*ip);
  863 
  864                 CARPSTATS_INC(carps_opackets);
  865 
  866                 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT,
  867                     &sc->sc_carpdev->if_carp->cif_imo, NULL));
  868         }
  869 #endif /* INET */
  870 #ifdef INET6
  871         if (sc->sc_naddrs6) {
  872                 struct ip6_hdr *ip6;
  873 
  874                 m = m_gethdr(M_NOWAIT, MT_DATA);
  875                 if (m == NULL) {
  876                         CARPSTATS_INC(carps_onomem);
  877                         goto resched;
  878                 }
  879                 len = sizeof(*ip6) + sizeof(ch);
  880                 m->m_pkthdr.len = len;
  881                 m->m_pkthdr.rcvif = NULL;
  882                 m->m_len = len;
  883                 M_ALIGN(m, m->m_len);
  884                 m->m_flags |= M_MCAST;
  885                 ip6 = mtod(m, struct ip6_hdr *);
  886                 bzero(ip6, sizeof(*ip6));
  887                 ip6->ip6_vfc |= IPV6_VERSION;
  888                 ip6->ip6_hlim = CARP_DFLTTL;
  889                 ip6->ip6_nxt = IPPROTO_CARP;
  890                 bzero(&sa, sizeof(sa));
  891 
  892                 /* set the source address */
  893                 sa.sa_family = AF_INET6;
  894                 ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
  895                 if (ifa != NULL) {
  896                         bcopy(IFA_IN6(ifa), &ip6->ip6_src,
  897                             sizeof(struct in6_addr));
  898                         ifa_free(ifa);
  899                 } else
  900                         /* This should never happen with IPv6. */
  901                         bzero(&ip6->ip6_src, sizeof(struct in6_addr));
  902 
  903                 /* Set the multicast destination. */
  904                 ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
  905                 ip6->ip6_dst.s6_addr8[15] = 0x12;
  906                 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) {
  907                         m_freem(m);
  908                         CARP_DEBUG("%s: in6_setscope failed\n", __func__);
  909                         goto resched;
  910                 }
  911 
  912                 ch_ptr = (struct carp_header *)(&ip6[1]);
  913                 bcopy(&ch, ch_ptr, sizeof(ch));
  914                 if (carp_prepare_ad(m, sc, ch_ptr))
  915                         goto resched;
  916 
  917                 m->m_data += sizeof(*ip6);
  918                 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6));
  919                 m->m_data -= sizeof(*ip6);
  920 
  921                 CARPSTATS_INC(carps_opackets6);
  922 
  923                 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0,
  924                     &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL));
  925         }
  926 #endif /* INET6 */
  927 
  928 resched:
  929         callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc);
  930 }
  931 
  932 static void
  933 carp_addroute(struct carp_softc *sc)
  934 {
  935         struct ifaddr *ifa;
  936 
  937         CARP_FOREACH_IFA(sc, ifa)
  938                 carp_ifa_addroute(ifa);
  939 }
  940 
  941 static void
  942 carp_ifa_addroute(struct ifaddr *ifa)
  943 {
  944 
  945         switch (ifa->ifa_addr->sa_family) {
  946 #ifdef INET
  947         case AF_INET:
  948                 in_addprefix(ifatoia(ifa), RTF_UP);
  949                 ifa_add_loopback_route(ifa,
  950                     (struct sockaddr *)&ifatoia(ifa)->ia_addr);
  951                 break;
  952 #endif
  953 #ifdef INET6
  954         case AF_INET6:
  955                 ifa_add_loopback_route(ifa,
  956                     (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
  957                 nd6_add_ifa_lle(ifatoia6(ifa));
  958                 break;
  959 #endif
  960         }
  961 }
  962 
  963 static void
  964 carp_delroute(struct carp_softc *sc)
  965 {
  966         struct ifaddr *ifa;
  967 
  968         CARP_FOREACH_IFA(sc, ifa)
  969                 carp_ifa_delroute(ifa);
  970 }
  971 
  972 static void
  973 carp_ifa_delroute(struct ifaddr *ifa)
  974 {
  975 
  976         switch (ifa->ifa_addr->sa_family) {
  977 #ifdef INET
  978         case AF_INET:
  979                 ifa_del_loopback_route(ifa,
  980                     (struct sockaddr *)&ifatoia(ifa)->ia_addr);
  981                 in_scrubprefix(ifatoia(ifa), LLE_STATIC);
  982                 break;
  983 #endif
  984 #ifdef INET6
  985         case AF_INET6:
  986                 ifa_del_loopback_route(ifa,
  987                     (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
  988                 nd6_rem_ifa_lle(ifatoia6(ifa), 1);
  989                 break;
  990 #endif
  991         }
  992 }
  993 
  994 int
  995 carp_master(struct ifaddr *ifa)
  996 {
  997         struct carp_softc *sc = ifa->ifa_carp;
  998 
  999         return (sc->sc_state == MASTER);
 1000 }
 1001 
 1002 #ifdef INET
 1003 /*
 1004  * Broadcast a gratuitous ARP request containing
 1005  * the virtual router MAC address for each IP address
 1006  * associated with the virtual router.
 1007  */
 1008 static void
 1009 carp_send_arp(struct carp_softc *sc)
 1010 {
 1011         struct ifaddr *ifa;
 1012         struct in_addr addr;
 1013 
 1014         CARP_FOREACH_IFA(sc, ifa) {
 1015                 if (ifa->ifa_addr->sa_family != AF_INET)
 1016                         continue;
 1017                 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
 1018                 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr));
 1019         }
 1020 }
 1021 
 1022 int
 1023 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr)
 1024 {
 1025         struct carp_softc *sc = ifa->ifa_carp;
 1026 
 1027         if (sc->sc_state == MASTER) {
 1028                 *enaddr = LLADDR(&sc->sc_addr);
 1029                 return (1);
 1030         }
 1031 
 1032         return (0);
 1033 }
 1034 #endif
 1035 
 1036 #ifdef INET6
 1037 static void
 1038 carp_send_na(struct carp_softc *sc)
 1039 {
 1040         static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
 1041         struct ifaddr *ifa;
 1042         struct in6_addr *in6;
 1043 
 1044         CARP_FOREACH_IFA(sc, ifa) {
 1045                 if (ifa->ifa_addr->sa_family != AF_INET6)
 1046                         continue;
 1047 
 1048                 in6 = IFA_IN6(ifa);
 1049                 nd6_na_output(sc->sc_carpdev, &mcast, in6,
 1050                     ND_NA_FLAG_OVERRIDE, 1, NULL);
 1051                 DELAY(1000);    /* XXX */
 1052         }
 1053 }
 1054 
 1055 /*
 1056  * Returns ifa in case it's a carp address and it is MASTER, or if the address
 1057  * matches and is not a carp address.  Returns NULL otherwise.
 1058  */
 1059 struct ifaddr *
 1060 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr)
 1061 {
 1062         struct ifaddr *ifa;
 1063 
 1064         ifa = NULL;
 1065         IF_ADDR_RLOCK(ifp);
 1066         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 1067                 if (ifa->ifa_addr->sa_family != AF_INET6)
 1068                         continue;
 1069                 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa)))
 1070                         continue;
 1071                 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER)
 1072                         ifa = NULL;
 1073                 else
 1074                         ifa_ref(ifa);
 1075                 break;
 1076         }
 1077         IF_ADDR_RUNLOCK(ifp);
 1078 
 1079         return (ifa);
 1080 }
 1081 
 1082 caddr_t
 1083 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr)
 1084 {
 1085         struct ifaddr *ifa;
 1086 
 1087         IF_ADDR_RLOCK(ifp);
 1088         IFNET_FOREACH_IFA(ifp, ifa)
 1089                 if (ifa->ifa_addr->sa_family == AF_INET6 &&
 1090                     IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) {
 1091                         struct carp_softc *sc = ifa->ifa_carp;
 1092                         struct m_tag *mtag;
 1093 
 1094                         IF_ADDR_RUNLOCK(ifp);
 1095 
 1096                         mtag = m_tag_get(PACKET_TAG_CARP,
 1097                             sizeof(struct carp_softc *), M_NOWAIT);
 1098                         if (mtag == NULL)
 1099                                 /* Better a bit than nothing. */
 1100                                 return (LLADDR(&sc->sc_addr));
 1101 
 1102                         bcopy(&sc, mtag + 1, sizeof(sc));
 1103                         m_tag_prepend(m, mtag);
 1104 
 1105                         return (LLADDR(&sc->sc_addr));
 1106                 }
 1107         IF_ADDR_RUNLOCK(ifp);
 1108 
 1109         return (NULL);
 1110 }
 1111 #endif /* INET6 */
 1112 
 1113 int
 1114 carp_forus(struct ifnet *ifp, u_char *dhost)
 1115 {
 1116         struct carp_softc *sc;
 1117         uint8_t *ena = dhost;
 1118 
 1119         if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
 1120                 return (0);
 1121 
 1122         CIF_LOCK(ifp->if_carp);
 1123         IFNET_FOREACH_CARP(ifp, sc) {
 1124                 CARP_LOCK(sc);
 1125                 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr),
 1126                     ETHER_ADDR_LEN)) {
 1127                         CARP_UNLOCK(sc);
 1128                         CIF_UNLOCK(ifp->if_carp);
 1129                         return (1);
 1130                 }
 1131                 CARP_UNLOCK(sc);
 1132         }
 1133         CIF_UNLOCK(ifp->if_carp);
 1134 
 1135         return (0);
 1136 }
 1137 
 1138 /* Master down timeout event, executed in callout context. */
 1139 static void
 1140 carp_master_down(void *v)
 1141 {
 1142         struct carp_softc *sc = v;
 1143 
 1144         CARP_LOCK_ASSERT(sc);
 1145 
 1146         CURVNET_SET(sc->sc_carpdev->if_vnet);
 1147         if (sc->sc_state == BACKUP) {
 1148                 carp_master_down_locked(sc, "master timed out");
 1149         }
 1150         CURVNET_RESTORE();
 1151 
 1152         CARP_UNLOCK(sc);
 1153 }
 1154 
 1155 static void
 1156 carp_master_down_locked(struct carp_softc *sc, const char *reason)
 1157 {
 1158 
 1159         CARP_LOCK_ASSERT(sc);
 1160 
 1161         switch (sc->sc_state) {
 1162         case BACKUP:
 1163                 carp_set_state(sc, MASTER, reason);
 1164                 carp_send_ad_locked(sc);
 1165 #ifdef INET
 1166                 carp_send_arp(sc);
 1167 #endif
 1168 #ifdef INET6
 1169                 carp_send_na(sc);
 1170 #endif
 1171                 carp_setrun(sc, 0);
 1172                 carp_addroute(sc);
 1173                 break;
 1174         case INIT:
 1175         case MASTER:
 1176 #ifdef INVARIANTS
 1177                 panic("carp: VHID %u@%s: master_down event in %s state\n",
 1178                     sc->sc_vhid,
 1179                     sc->sc_carpdev->if_xname,
 1180                     sc->sc_state ? "MASTER" : "INIT");
 1181 #endif
 1182                 break;
 1183         }
 1184 }
 1185 
 1186 /*
 1187  * When in backup state, af indicates whether to reset the master down timer
 1188  * for v4 or v6. If it's set to zero, reset the ones which are already pending.
 1189  */
 1190 static void
 1191 carp_setrun(struct carp_softc *sc, sa_family_t af)
 1192 {
 1193         struct timeval tv;
 1194 
 1195         CARP_LOCK_ASSERT(sc);
 1196 
 1197         if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 ||
 1198             sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
 1199             (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0))
 1200                 return;
 1201 
 1202         switch (sc->sc_state) {
 1203         case INIT:
 1204                 carp_set_state(sc, BACKUP, "initialization complete");
 1205                 carp_setrun(sc, 0);
 1206                 break;
 1207         case BACKUP:
 1208                 callout_stop(&sc->sc_ad_tmo);
 1209                 tv.tv_sec = 3 * sc->sc_advbase;
 1210                 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
 1211                 switch (af) {
 1212 #ifdef INET
 1213                 case AF_INET:
 1214                         callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
 1215                             carp_master_down, sc);
 1216                         break;
 1217 #endif
 1218 #ifdef INET6
 1219                 case AF_INET6:
 1220                         callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
 1221                             carp_master_down, sc);
 1222                         break;
 1223 #endif
 1224                 default:
 1225 #ifdef INET
 1226                         if (sc->sc_naddrs)
 1227                                 callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
 1228                                     carp_master_down, sc);
 1229 #endif
 1230 #ifdef INET6
 1231                         if (sc->sc_naddrs6)
 1232                                 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
 1233                                     carp_master_down, sc);
 1234 #endif
 1235                         break;
 1236                 }
 1237                 break;
 1238         case MASTER:
 1239                 tv.tv_sec = sc->sc_advbase;
 1240                 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
 1241                 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
 1242                     carp_send_ad, sc);
 1243                 break;
 1244         }
 1245 }
 1246 
 1247 /*
 1248  * Setup multicast structures.
 1249  */
 1250 static int
 1251 carp_multicast_setup(struct carp_if *cif, sa_family_t sa)
 1252 {
 1253         struct ifnet *ifp = cif->cif_ifp;
 1254         int error = 0;
 1255 
 1256         switch (sa) {
 1257 #ifdef INET
 1258         case AF_INET:
 1259             {
 1260                 struct ip_moptions *imo = &cif->cif_imo;
 1261                 struct in_addr addr;
 1262 
 1263                 if (imo->imo_membership)
 1264                         return (0);
 1265 
 1266                 imo->imo_membership = (struct in_multi **)malloc(
 1267                     (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP,
 1268                     M_WAITOK);
 1269                 imo->imo_mfilters = NULL;
 1270                 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS;
 1271                 imo->imo_multicast_vif = -1;
 1272 
 1273                 addr.s_addr = htonl(INADDR_CARP_GROUP);
 1274                 if ((error = in_joingroup(ifp, &addr, NULL,
 1275                     &imo->imo_membership[0])) != 0) {
 1276                         free(imo->imo_membership, M_CARP);
 1277                         break;
 1278                 }
 1279                 imo->imo_num_memberships++;
 1280                 imo->imo_multicast_ifp = ifp;
 1281                 imo->imo_multicast_ttl = CARP_DFLTTL;
 1282                 imo->imo_multicast_loop = 0;
 1283                 break;
 1284            }
 1285 #endif
 1286 #ifdef INET6
 1287         case AF_INET6:
 1288             {
 1289                 struct ip6_moptions *im6o = &cif->cif_im6o;
 1290                 struct in6_addr in6;
 1291                 struct in6_multi *in6m;
 1292 
 1293                 if (im6o->im6o_membership)
 1294                         return (0);
 1295 
 1296                 im6o->im6o_membership = (struct in6_multi **)malloc(
 1297                     (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP,
 1298                     M_ZERO | M_WAITOK);
 1299                 im6o->im6o_mfilters = NULL;
 1300                 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS;
 1301                 im6o->im6o_multicast_hlim = CARP_DFLTTL;
 1302                 im6o->im6o_multicast_ifp = ifp;
 1303 
 1304                 /* Join IPv6 CARP multicast group. */
 1305                 bzero(&in6, sizeof(in6));
 1306                 in6.s6_addr16[0] = htons(0xff02);
 1307                 in6.s6_addr8[15] = 0x12;
 1308                 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
 1309                         free(im6o->im6o_membership, M_CARP);
 1310                         break;
 1311                 }
 1312                 in6m = NULL;
 1313                 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) {
 1314                         free(im6o->im6o_membership, M_CARP);
 1315                         break;
 1316                 }
 1317                 im6o->im6o_membership[0] = in6m;
 1318                 im6o->im6o_num_memberships++;
 1319 
 1320                 /* Join solicited multicast address. */
 1321                 bzero(&in6, sizeof(in6));
 1322                 in6.s6_addr16[0] = htons(0xff02);
 1323                 in6.s6_addr32[1] = 0;
 1324                 in6.s6_addr32[2] = htonl(1);
 1325                 in6.s6_addr32[3] = 0;
 1326                 in6.s6_addr8[12] = 0xff;
 1327                 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
 1328                         in6_mc_leave(im6o->im6o_membership[0], NULL);
 1329                         free(im6o->im6o_membership, M_CARP);
 1330                         break;
 1331                 }
 1332                 in6m = NULL;
 1333                 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) {
 1334                         in6_mc_leave(im6o->im6o_membership[0], NULL);
 1335                         free(im6o->im6o_membership, M_CARP);
 1336                         break;
 1337                 }
 1338                 im6o->im6o_membership[1] = in6m;
 1339                 im6o->im6o_num_memberships++;
 1340                 break;
 1341             }
 1342 #endif
 1343         }
 1344 
 1345         return (error);
 1346 }
 1347 
 1348 /*
 1349  * Free multicast structures.
 1350  */
 1351 static void
 1352 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa)
 1353 {
 1354 
 1355         sx_assert(&carp_sx, SA_XLOCKED);
 1356 
 1357         switch (sa) {
 1358 #ifdef INET
 1359         case AF_INET:
 1360                 if (cif->cif_naddrs == 0) {
 1361                         struct ip_moptions *imo = &cif->cif_imo;
 1362 
 1363                         in_leavegroup(imo->imo_membership[0], NULL);
 1364                         KASSERT(imo->imo_mfilters == NULL,
 1365                             ("%s: imo_mfilters != NULL", __func__));
 1366                         free(imo->imo_membership, M_CARP);
 1367                         imo->imo_membership = NULL;
 1368 
 1369                 }
 1370                 break;
 1371 #endif
 1372 #ifdef INET6
 1373         case AF_INET6:
 1374                 if (cif->cif_naddrs6 == 0) {
 1375                         struct ip6_moptions *im6o = &cif->cif_im6o;
 1376 
 1377                         in6_mc_leave(im6o->im6o_membership[0], NULL);
 1378                         in6_mc_leave(im6o->im6o_membership[1], NULL);
 1379                         KASSERT(im6o->im6o_mfilters == NULL,
 1380                             ("%s: im6o_mfilters != NULL", __func__));
 1381                         free(im6o->im6o_membership, M_CARP);
 1382                         im6o->im6o_membership = NULL;
 1383                 }
 1384                 break;
 1385 #endif
 1386         }
 1387 }
 1388 
 1389 int
 1390 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa)
 1391 {
 1392         struct m_tag *mtag;
 1393         struct carp_softc *sc;
 1394 
 1395         if (!sa)
 1396                 return (0);
 1397 
 1398         switch (sa->sa_family) {
 1399 #ifdef INET
 1400         case AF_INET:
 1401                 break;
 1402 #endif
 1403 #ifdef INET6
 1404         case AF_INET6:
 1405                 break;
 1406 #endif
 1407         default:
 1408                 return (0);
 1409         }
 1410 
 1411         mtag = m_tag_find(m, PACKET_TAG_CARP, NULL);
 1412         if (mtag == NULL)
 1413                 return (0);
 1414 
 1415         bcopy(mtag + 1, &sc, sizeof(sc));
 1416 
 1417         /* Set the source MAC address to the Virtual Router MAC Address. */
 1418         switch (ifp->if_type) {
 1419         case IFT_ETHER:
 1420         case IFT_BRIDGE:
 1421         case IFT_L2VLAN: {
 1422                         struct ether_header *eh;
 1423 
 1424                         eh = mtod(m, struct ether_header *);
 1425                         eh->ether_shost[0] = 0;
 1426                         eh->ether_shost[1] = 0;
 1427                         eh->ether_shost[2] = 0x5e;
 1428                         eh->ether_shost[3] = 0;
 1429                         eh->ether_shost[4] = 1;
 1430                         eh->ether_shost[5] = sc->sc_vhid;
 1431                 }
 1432                 break;
 1433         case IFT_FDDI: {
 1434                         struct fddi_header *fh;
 1435 
 1436                         fh = mtod(m, struct fddi_header *);
 1437                         fh->fddi_shost[0] = 0;
 1438                         fh->fddi_shost[1] = 0;
 1439                         fh->fddi_shost[2] = 0x5e;
 1440                         fh->fddi_shost[3] = 0;
 1441                         fh->fddi_shost[4] = 1;
 1442                         fh->fddi_shost[5] = sc->sc_vhid;
 1443                 }
 1444                 break;
 1445         case IFT_ISO88025: {
 1446                         struct iso88025_header *th;
 1447                         th = mtod(m, struct iso88025_header *);
 1448                         th->iso88025_shost[0] = 3;
 1449                         th->iso88025_shost[1] = 0;
 1450                         th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1);
 1451                         th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1);
 1452                         th->iso88025_shost[4] = 0;
 1453                         th->iso88025_shost[5] = 0;
 1454                 }
 1455                 break;
 1456         default:
 1457                 printf("%s: carp is not supported for the %d interface type\n",
 1458                     ifp->if_xname, ifp->if_type);
 1459                 return (EOPNOTSUPP);
 1460         }
 1461 
 1462         return (0);
 1463 }
 1464 
 1465 static struct carp_softc*
 1466 carp_alloc(struct ifnet *ifp)
 1467 {
 1468         struct carp_softc *sc;
 1469         struct carp_if *cif;
 1470 
 1471         if ((cif = ifp->if_carp) == NULL)
 1472                 cif = carp_alloc_if(ifp);
 1473 
 1474         sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO);
 1475 
 1476         sc->sc_advbase = CARP_DFLTINTV;
 1477         sc->sc_vhid = -1;       /* required setting */
 1478         sc->sc_init_counter = 1;
 1479         sc->sc_state = INIT;
 1480 
 1481         sc->sc_ifasiz = sizeof(struct ifaddr *);
 1482         sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO);
 1483         sc->sc_carpdev = ifp;
 1484 
 1485         CARP_LOCK_INIT(sc);
 1486 #ifdef INET
 1487         callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
 1488 #endif
 1489 #ifdef INET6
 1490         callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
 1491 #endif
 1492         callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
 1493 
 1494         CIF_LOCK(cif);
 1495         TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list);
 1496         CIF_UNLOCK(cif);
 1497 
 1498         mtx_lock(&carp_mtx);
 1499         LIST_INSERT_HEAD(&carp_list, sc, sc_next);
 1500         mtx_unlock(&carp_mtx);
 1501 
 1502         return (sc);
 1503 }
 1504 
 1505 static void
 1506 carp_grow_ifas(struct carp_softc *sc)
 1507 {
 1508         struct ifaddr **new;
 1509 
 1510         new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO);
 1511         CARP_LOCK(sc);
 1512         bcopy(sc->sc_ifas, new, sc->sc_ifasiz);
 1513         free(sc->sc_ifas, M_CARP);
 1514         sc->sc_ifas = new;
 1515         sc->sc_ifasiz *= 2;
 1516         CARP_UNLOCK(sc);
 1517 }
 1518 
 1519 static void
 1520 carp_destroy(struct carp_softc *sc)
 1521 {
 1522         struct ifnet *ifp = sc->sc_carpdev;
 1523         struct carp_if *cif = ifp->if_carp;
 1524 
 1525         sx_assert(&carp_sx, SA_XLOCKED);
 1526 
 1527         if (sc->sc_suppress)
 1528                 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed");
 1529         CARP_UNLOCK(sc);
 1530 
 1531         CIF_LOCK(cif);
 1532         TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list);
 1533         CIF_UNLOCK(cif);
 1534 
 1535         mtx_lock(&carp_mtx);
 1536         LIST_REMOVE(sc, sc_next);
 1537         mtx_unlock(&carp_mtx);
 1538 
 1539         callout_drain(&sc->sc_ad_tmo);
 1540 #ifdef INET
 1541         callout_drain(&sc->sc_md_tmo);
 1542 #endif
 1543 #ifdef INET6
 1544         callout_drain(&sc->sc_md6_tmo);
 1545 #endif
 1546         CARP_LOCK_DESTROY(sc);
 1547 
 1548         free(sc->sc_ifas, M_CARP);
 1549         free(sc, M_CARP);
 1550 }
 1551 
 1552 static struct carp_if*
 1553 carp_alloc_if(struct ifnet *ifp)
 1554 {
 1555         struct carp_if *cif;
 1556         int error;
 1557 
 1558         cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO);
 1559 
 1560         if ((error = ifpromisc(ifp, 1)) != 0)
 1561                 printf("%s: ifpromisc(%s) failed: %d\n",
 1562                     __func__, ifp->if_xname, error);
 1563         else
 1564                 cif->cif_flags |= CIF_PROMISC;
 1565 
 1566         CIF_LOCK_INIT(cif);
 1567         cif->cif_ifp = ifp;
 1568         TAILQ_INIT(&cif->cif_vrs);
 1569 
 1570         IF_ADDR_WLOCK(ifp);
 1571         ifp->if_carp = cif;
 1572         if_ref(ifp);
 1573         IF_ADDR_WUNLOCK(ifp);
 1574 
 1575         return (cif);
 1576 }
 1577 
 1578 static void
 1579 carp_free_if(struct carp_if *cif)
 1580 {
 1581         struct ifnet *ifp = cif->cif_ifp;
 1582 
 1583         CIF_LOCK_ASSERT(cif);
 1584         KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty",
 1585             __func__));
 1586 
 1587         IF_ADDR_WLOCK(ifp);
 1588         ifp->if_carp = NULL;
 1589         IF_ADDR_WUNLOCK(ifp);
 1590 
 1591         CIF_LOCK_DESTROY(cif);
 1592 
 1593         if (cif->cif_flags & CIF_PROMISC)
 1594                 ifpromisc(ifp, 0);
 1595         if_rele(ifp);
 1596 
 1597         free(cif, M_CARP);
 1598 }
 1599 
 1600 static void
 1601 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv)
 1602 {
 1603 
 1604         CARP_LOCK(sc);
 1605         carpr->carpr_state = sc->sc_state;
 1606         carpr->carpr_vhid = sc->sc_vhid;
 1607         carpr->carpr_advbase = sc->sc_advbase;
 1608         carpr->carpr_advskew = sc->sc_advskew;
 1609         if (priv)
 1610                 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key));
 1611         else
 1612                 bzero(carpr->carpr_key, sizeof(carpr->carpr_key));
 1613         CARP_UNLOCK(sc);
 1614 }
 1615 
 1616 int
 1617 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td)
 1618 {
 1619         struct carpreq carpr;
 1620         struct ifnet *ifp;
 1621         struct carp_softc *sc = NULL;
 1622         int error = 0, locked = 0;
 1623 
 1624         if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr)))
 1625                 return (error);
 1626 
 1627         ifp = ifunit_ref(ifr->ifr_name);
 1628         if (ifp == NULL)
 1629                 return (ENXIO);
 1630 
 1631         switch (ifp->if_type) {
 1632         case IFT_ETHER:
 1633         case IFT_L2VLAN:
 1634         case IFT_BRIDGE:
 1635         case IFT_FDDI:
 1636         case IFT_ISO88025:
 1637                 break;
 1638         default:
 1639                 error = EOPNOTSUPP;
 1640                 goto out;
 1641         }
 1642 
 1643         if ((ifp->if_flags & IFF_MULTICAST) == 0) {
 1644                 error = EADDRNOTAVAIL;
 1645                 goto out;
 1646         }
 1647 
 1648         sx_xlock(&carp_sx);
 1649         switch (cmd) {
 1650         case SIOCSVH:
 1651                 if ((error = priv_check(td, PRIV_NETINET_CARP)))
 1652                         break;
 1653                 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID ||
 1654                     carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) {
 1655                         error = EINVAL;
 1656                         break;
 1657                 }
 1658 
 1659                 if (ifp->if_carp) {
 1660                         CIF_LOCK(ifp->if_carp);
 1661                         IFNET_FOREACH_CARP(ifp, sc)
 1662                                 if (sc->sc_vhid == carpr.carpr_vhid)
 1663                                         break;
 1664                         CIF_UNLOCK(ifp->if_carp);
 1665                 }
 1666                 if (sc == NULL) {
 1667                         sc = carp_alloc(ifp);
 1668                         CARP_LOCK(sc);
 1669                         sc->sc_vhid = carpr.carpr_vhid;
 1670                         LLADDR(&sc->sc_addr)[0] = 0;
 1671                         LLADDR(&sc->sc_addr)[1] = 0;
 1672                         LLADDR(&sc->sc_addr)[2] = 0x5e;
 1673                         LLADDR(&sc->sc_addr)[3] = 0;
 1674                         LLADDR(&sc->sc_addr)[4] = 1;
 1675                         LLADDR(&sc->sc_addr)[5] = sc->sc_vhid;
 1676                 } else
 1677                         CARP_LOCK(sc);
 1678                 locked = 1;
 1679                 if (carpr.carpr_advbase > 0) {
 1680                         if (carpr.carpr_advbase > 255 ||
 1681                             carpr.carpr_advbase < CARP_DFLTINTV) {
 1682                                 error = EINVAL;
 1683                                 break;
 1684                         }
 1685                         sc->sc_advbase = carpr.carpr_advbase;
 1686                 }
 1687                 if (carpr.carpr_advskew >= 255) {
 1688                         error = EINVAL;
 1689                         break;
 1690                 }
 1691                 sc->sc_advskew = carpr.carpr_advskew;
 1692                 if (carpr.carpr_key[0] != '\0') {
 1693                         bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key));
 1694                         carp_hmac_prepare(sc);
 1695                 }
 1696                 if (sc->sc_state != INIT &&
 1697                     carpr.carpr_state != sc->sc_state) {
 1698                         switch (carpr.carpr_state) {
 1699                         case BACKUP:
 1700                                 callout_stop(&sc->sc_ad_tmo);
 1701                                 carp_set_state(sc, BACKUP,
 1702                                     "user requested via ifconfig");
 1703                                 carp_setrun(sc, 0);
 1704                                 carp_delroute(sc);
 1705                                 break;
 1706                         case MASTER:
 1707                                 carp_master_down_locked(sc,
 1708                                     "user requested via ifconfig");
 1709                                 break;
 1710                         default:
 1711                                 break;
 1712                         }
 1713                 }
 1714                 break;
 1715 
 1716         case SIOCGVH:
 1717             {
 1718                 int priveleged;
 1719 
 1720                 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) {
 1721                         error = EINVAL;
 1722                         break;
 1723                 }
 1724                 if (carpr.carpr_count < 1) {
 1725                         error = EMSGSIZE;
 1726                         break;
 1727                 }
 1728                 if (ifp->if_carp == NULL) {
 1729                         error = ENOENT;
 1730                         break;
 1731                 }
 1732 
 1733                 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0);
 1734                 if (carpr.carpr_vhid != 0) {
 1735                         CIF_LOCK(ifp->if_carp);
 1736                         IFNET_FOREACH_CARP(ifp, sc)
 1737                                 if (sc->sc_vhid == carpr.carpr_vhid)
 1738                                         break;
 1739                         CIF_UNLOCK(ifp->if_carp);
 1740                         if (sc == NULL) {
 1741                                 error = ENOENT;
 1742                                 break;
 1743                         }
 1744                         carp_carprcp(&carpr, sc, priveleged);
 1745                         error = copyout(&carpr, ifr->ifr_data, sizeof(carpr));
 1746                 } else  {
 1747                         int i, count;
 1748 
 1749                         count = 0;
 1750                         CIF_LOCK(ifp->if_carp);
 1751                         IFNET_FOREACH_CARP(ifp, sc)
 1752                                 count++;
 1753 
 1754                         if (count > carpr.carpr_count) {
 1755                                 CIF_UNLOCK(ifp->if_carp);
 1756                                 error = EMSGSIZE;
 1757                                 break;
 1758                         }
 1759 
 1760                         i = 0;
 1761                         IFNET_FOREACH_CARP(ifp, sc) {
 1762                                 carp_carprcp(&carpr, sc, priveleged);
 1763                                 carpr.carpr_count = count;
 1764                                 error = copyout(&carpr, ifr->ifr_data +
 1765                                     (i * sizeof(carpr)), sizeof(carpr));
 1766                                 if (error) {
 1767                                         CIF_UNLOCK(ifp->if_carp);
 1768                                         break;
 1769                                 }
 1770                                 i++;
 1771                         }
 1772                         CIF_UNLOCK(ifp->if_carp);
 1773                 }
 1774                 break;
 1775             }
 1776         default:
 1777                 error = EINVAL;
 1778         }
 1779         sx_xunlock(&carp_sx);
 1780 
 1781 out:
 1782         if (locked)
 1783                 CARP_UNLOCK(sc);
 1784         if_rele(ifp);
 1785 
 1786         return (error);
 1787 }
 1788 
 1789 static int
 1790 carp_get_vhid(struct ifaddr *ifa)
 1791 {
 1792 
 1793         if (ifa == NULL || ifa->ifa_carp == NULL)
 1794                 return (0);
 1795 
 1796         return (ifa->ifa_carp->sc_vhid);
 1797 }
 1798 
 1799 int
 1800 carp_attach(struct ifaddr *ifa, int vhid)
 1801 {
 1802         struct ifnet *ifp = ifa->ifa_ifp;
 1803         struct carp_if *cif = ifp->if_carp;
 1804         struct carp_softc *sc;
 1805         int index, error;
 1806 
 1807         KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa));
 1808 
 1809         switch (ifa->ifa_addr->sa_family) {
 1810 #ifdef INET
 1811         case AF_INET:
 1812 #endif
 1813 #ifdef INET6
 1814         case AF_INET6:
 1815 #endif
 1816                 break;
 1817         default:
 1818                 return (EPROTOTYPE);
 1819         }
 1820 
 1821         sx_xlock(&carp_sx);
 1822         if (ifp->if_carp == NULL) {
 1823                 sx_xunlock(&carp_sx);
 1824                 return (ENOPROTOOPT);
 1825         }
 1826 
 1827         CIF_LOCK(cif);
 1828         IFNET_FOREACH_CARP(ifp, sc)
 1829                 if (sc->sc_vhid == vhid)
 1830                         break;
 1831         CIF_UNLOCK(cif);
 1832         if (sc == NULL) {
 1833                 sx_xunlock(&carp_sx);
 1834                 return (ENOENT);
 1835         }
 1836 
 1837         error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family);
 1838         if (error) {
 1839                 CIF_FREE(cif);
 1840                 sx_xunlock(&carp_sx);
 1841                 return (error);
 1842         }
 1843 
 1844         index = sc->sc_naddrs + sc->sc_naddrs6 + 1;
 1845         if (index > sc->sc_ifasiz / sizeof(struct ifaddr *))
 1846                 carp_grow_ifas(sc);
 1847 
 1848         switch (ifa->ifa_addr->sa_family) {
 1849 #ifdef INET
 1850         case AF_INET:
 1851                 cif->cif_naddrs++;
 1852                 sc->sc_naddrs++;
 1853                 break;
 1854 #endif
 1855 #ifdef INET6
 1856         case AF_INET6:
 1857                 cif->cif_naddrs6++;
 1858                 sc->sc_naddrs6++;
 1859                 break;
 1860 #endif
 1861         }
 1862 
 1863         ifa_ref(ifa);
 1864 
 1865         CARP_LOCK(sc);
 1866         sc->sc_ifas[index - 1] = ifa;
 1867         ifa->ifa_carp = sc;
 1868         carp_hmac_prepare(sc);
 1869         carp_sc_state(sc);
 1870         CARP_UNLOCK(sc);
 1871 
 1872         sx_xunlock(&carp_sx);
 1873 
 1874         return (0);
 1875 }
 1876 
 1877 void
 1878 carp_detach(struct ifaddr *ifa)
 1879 {
 1880         struct ifnet *ifp = ifa->ifa_ifp;
 1881         struct carp_if *cif = ifp->if_carp;
 1882         struct carp_softc *sc = ifa->ifa_carp;
 1883         int i, index;
 1884 
 1885         KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa));
 1886 
 1887         sx_xlock(&carp_sx);
 1888 
 1889         CARP_LOCK(sc);
 1890         /* Shift array. */
 1891         index = sc->sc_naddrs + sc->sc_naddrs6;
 1892         for (i = 0; i < index; i++)
 1893                 if (sc->sc_ifas[i] == ifa)
 1894                         break;
 1895         KASSERT(i < index, ("%s: %p no backref", __func__, ifa));
 1896         for (; i < index - 1; i++)
 1897                 sc->sc_ifas[i] = sc->sc_ifas[i+1];
 1898         sc->sc_ifas[index - 1] = NULL;
 1899 
 1900         switch (ifa->ifa_addr->sa_family) {
 1901 #ifdef INET
 1902         case AF_INET:
 1903                 cif->cif_naddrs--;
 1904                 sc->sc_naddrs--;
 1905                 break;
 1906 #endif
 1907 #ifdef INET6
 1908         case AF_INET6:
 1909                 cif->cif_naddrs6--;
 1910                 sc->sc_naddrs6--;
 1911                 break;
 1912 #endif
 1913         }
 1914 
 1915         carp_ifa_delroute(ifa);
 1916         carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family);
 1917 
 1918         ifa->ifa_carp = NULL;
 1919         ifa_free(ifa);
 1920 
 1921         carp_hmac_prepare(sc);
 1922         carp_sc_state(sc);
 1923 
 1924         if (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0)
 1925                 carp_destroy(sc);
 1926         else
 1927                 CARP_UNLOCK(sc);
 1928 
 1929         CIF_FREE(cif);
 1930 
 1931         sx_xunlock(&carp_sx);
 1932 }
 1933 
 1934 static void
 1935 carp_set_state(struct carp_softc *sc, int state, const char *reason)
 1936 {
 1937 
 1938         CARP_LOCK_ASSERT(sc);
 1939 
 1940         if (sc->sc_state != state) {
 1941                 const char *carp_states[] = { CARP_STATES };
 1942                 char subsys[IFNAMSIZ+5];
 1943 
 1944                 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid,
 1945                     sc->sc_carpdev->if_xname);
 1946 
 1947                 CARP_LOG("%s: %s -> %s (%s)\n", subsys,
 1948                     carp_states[sc->sc_state], carp_states[state], reason);
 1949 
 1950                 sc->sc_state = state;
 1951 
 1952                 devctl_notify("CARP", subsys, carp_states[state], NULL);
 1953         }
 1954 }
 1955 
 1956 static void
 1957 carp_linkstate(struct ifnet *ifp)
 1958 {
 1959         struct carp_softc *sc;
 1960 
 1961         CIF_LOCK(ifp->if_carp);
 1962         IFNET_FOREACH_CARP(ifp, sc) {
 1963                 CARP_LOCK(sc);
 1964                 carp_sc_state(sc);
 1965                 CARP_UNLOCK(sc);
 1966         }
 1967         CIF_UNLOCK(ifp->if_carp);
 1968 }
 1969 
 1970 static void
 1971 carp_sc_state(struct carp_softc *sc)
 1972 {
 1973 
 1974         CARP_LOCK_ASSERT(sc);
 1975 
 1976         if (sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
 1977             !(sc->sc_carpdev->if_flags & IFF_UP)) {
 1978                 callout_stop(&sc->sc_ad_tmo);
 1979 #ifdef INET
 1980                 callout_stop(&sc->sc_md_tmo);
 1981 #endif
 1982 #ifdef INET6
 1983                 callout_stop(&sc->sc_md6_tmo);
 1984 #endif
 1985                 carp_set_state(sc, INIT, "hardware interface down");
 1986                 carp_setrun(sc, 0);
 1987                 if (!sc->sc_suppress)
 1988                         carp_demote_adj(V_carp_ifdown_adj, "interface down");
 1989                 sc->sc_suppress = 1;
 1990         } else {
 1991                 carp_set_state(sc, INIT, "hardware interface up");
 1992                 carp_setrun(sc, 0);
 1993                 if (sc->sc_suppress)
 1994                         carp_demote_adj(-V_carp_ifdown_adj, "interface up");
 1995                 sc->sc_suppress = 0;
 1996         }
 1997 }
 1998 
 1999 static void
 2000 carp_demote_adj(int adj, char *reason)
 2001 {
 2002         atomic_add_int(&V_carp_demotion, adj);
 2003         CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason);
 2004         taskqueue_enqueue(taskqueue_swi, &carp_sendall_task);
 2005 }
 2006 
 2007 static int
 2008 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS)
 2009 {
 2010         int new, error;
 2011 
 2012         new = V_carp_demotion;
 2013         error = sysctl_handle_int(oidp, &new, 0, req);
 2014         if (error || !req->newptr)
 2015                 return (error);
 2016 
 2017         carp_demote_adj(new, "sysctl");
 2018 
 2019         return (0);
 2020 }
 2021 
 2022 #ifdef INET
 2023 extern  struct domain inetdomain;
 2024 static struct protosw in_carp_protosw = {
 2025         .pr_type =              SOCK_RAW,
 2026         .pr_domain =            &inetdomain,
 2027         .pr_protocol =          IPPROTO_CARP,
 2028         .pr_flags =             PR_ATOMIC|PR_ADDR,
 2029         .pr_input =             carp_input,
 2030         .pr_output =            rip_output,
 2031         .pr_ctloutput =         rip_ctloutput,
 2032         .pr_usrreqs =           &rip_usrreqs
 2033 };
 2034 #endif
 2035 
 2036 #ifdef INET6
 2037 extern  struct domain inet6domain;
 2038 static struct protosw in6_carp_protosw = {
 2039         .pr_type =              SOCK_RAW,
 2040         .pr_domain =            &inet6domain,
 2041         .pr_protocol =          IPPROTO_CARP,
 2042         .pr_flags =             PR_ATOMIC|PR_ADDR,
 2043         .pr_input =             carp6_input,
 2044         .pr_output =            rip6_output,
 2045         .pr_ctloutput =         rip6_ctloutput,
 2046         .pr_usrreqs =           &rip6_usrreqs
 2047 };
 2048 #endif
 2049 
 2050 static void
 2051 carp_mod_cleanup(void)
 2052 {
 2053 
 2054 #ifdef INET
 2055         if (proto_reg[CARP_INET] == 0) {
 2056                 (void)ipproto_unregister(IPPROTO_CARP);
 2057                 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW);
 2058                 proto_reg[CARP_INET] = -1;
 2059         }
 2060         carp_iamatch_p = NULL;
 2061 #endif
 2062 #ifdef INET6
 2063         if (proto_reg[CARP_INET6] == 0) {
 2064                 (void)ip6proto_unregister(IPPROTO_CARP);
 2065                 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW);
 2066                 proto_reg[CARP_INET6] = -1;
 2067         }
 2068         carp_iamatch6_p = NULL;
 2069         carp_macmatch6_p = NULL;
 2070 #endif
 2071         carp_ioctl_p = NULL;
 2072         carp_attach_p = NULL;
 2073         carp_detach_p = NULL;
 2074         carp_get_vhid_p = NULL;
 2075         carp_linkstate_p = NULL;
 2076         carp_forus_p = NULL;
 2077         carp_output_p = NULL;
 2078         carp_demote_adj_p = NULL;
 2079         carp_master_p = NULL;
 2080         mtx_unlock(&carp_mtx);
 2081         taskqueue_drain(taskqueue_swi, &carp_sendall_task);
 2082         mtx_destroy(&carp_mtx);
 2083         sx_destroy(&carp_sx);
 2084 }
 2085 
 2086 static int
 2087 carp_mod_load(void)
 2088 {
 2089         int err;
 2090 
 2091         mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF);
 2092         sx_init(&carp_sx, "carp_sx");
 2093         LIST_INIT(&carp_list);
 2094         carp_get_vhid_p = carp_get_vhid;
 2095         carp_forus_p = carp_forus;
 2096         carp_output_p = carp_output;
 2097         carp_linkstate_p = carp_linkstate;
 2098         carp_ioctl_p = carp_ioctl;
 2099         carp_attach_p = carp_attach;
 2100         carp_detach_p = carp_detach;
 2101         carp_demote_adj_p = carp_demote_adj;
 2102         carp_master_p = carp_master;
 2103 #ifdef INET6
 2104         carp_iamatch6_p = carp_iamatch6;
 2105         carp_macmatch6_p = carp_macmatch6;
 2106         proto_reg[CARP_INET6] = pf_proto_register(PF_INET6,
 2107             (struct protosw *)&in6_carp_protosw);
 2108         if (proto_reg[CARP_INET6]) {
 2109                 printf("carp: error %d attaching to PF_INET6\n",
 2110                     proto_reg[CARP_INET6]);
 2111                 carp_mod_cleanup();
 2112                 return (proto_reg[CARP_INET6]);
 2113         }
 2114         err = ip6proto_register(IPPROTO_CARP);
 2115         if (err) {
 2116                 printf("carp: error %d registering with INET6\n", err);
 2117                 carp_mod_cleanup();
 2118                 return (err);
 2119         }
 2120 #endif
 2121 #ifdef INET
 2122         carp_iamatch_p = carp_iamatch;
 2123         proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw);
 2124         if (proto_reg[CARP_INET]) {
 2125                 printf("carp: error %d attaching to PF_INET\n",
 2126                     proto_reg[CARP_INET]);
 2127                 carp_mod_cleanup();
 2128                 return (proto_reg[CARP_INET]);
 2129         }
 2130         err = ipproto_register(IPPROTO_CARP);
 2131         if (err) {
 2132                 printf("carp: error %d registering with INET\n", err);
 2133                 carp_mod_cleanup();
 2134                 return (err);
 2135         }
 2136 #endif
 2137         return (0);
 2138 }
 2139 
 2140 static int
 2141 carp_modevent(module_t mod, int type, void *data)
 2142 {
 2143         switch (type) {
 2144         case MOD_LOAD:
 2145                 return carp_mod_load();
 2146                 /* NOTREACHED */
 2147         case MOD_UNLOAD:
 2148                 mtx_lock(&carp_mtx);
 2149                 if (LIST_EMPTY(&carp_list))
 2150                         carp_mod_cleanup();
 2151                 else {
 2152                         mtx_unlock(&carp_mtx);
 2153                         return (EBUSY);
 2154                 }
 2155                 break;
 2156 
 2157         default:
 2158                 return (EINVAL);
 2159         }
 2160 
 2161         return (0);
 2162 }
 2163 
 2164 static moduledata_t carp_mod = {
 2165         "carp",
 2166         carp_modevent,
 2167         0
 2168 };
 2169 
 2170 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);

Cache object: 0029f4cb247f55a70e16d332743d735e


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.