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("$FreeBSD$"); 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() or carp_sx. 179 * To 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 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 290 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 291 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 292 293 #define DEMOTE_ADVSKEW(sc) \ 294 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 295 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) 296 297 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 298 static struct carp_softc 299 *carp_alloc(struct ifnet *); 300 static void carp_destroy(struct carp_softc *); 301 static struct carp_if 302 *carp_alloc_if(struct ifnet *); 303 static void carp_free_if(struct carp_if *); 304 static void carp_set_state(struct carp_softc *, int, const char* reason); 305 static void carp_sc_state(struct carp_softc *); 306 static void carp_setrun(struct carp_softc *, sa_family_t); 307 static void carp_master_down(void *); 308 static void carp_master_down_locked(struct carp_softc *, 309 const char* reason); 310 static void carp_send_ad(void *); 311 static void carp_send_ad_locked(struct carp_softc *); 312 static void carp_addroute(struct carp_softc *); 313 static void carp_ifa_addroute(struct ifaddr *); 314 static void carp_delroute(struct carp_softc *); 315 static void carp_ifa_delroute(struct ifaddr *); 316 static void carp_send_ad_all(void *, int); 317 static void carp_demote_adj(int, char *); 318 319 static LIST_HEAD(, carp_softc) carp_list; 320 static struct mtx carp_mtx; 321 static struct sx carp_sx; 322 static struct task carp_sendall_task = 323 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 324 325 static void 326 carp_hmac_prepare(struct carp_softc *sc) 327 { 328 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 329 uint8_t vhid = sc->sc_vhid & 0xff; 330 struct ifaddr *ifa; 331 int i, found; 332 #ifdef INET 333 struct in_addr last, cur, in; 334 #endif 335 #ifdef INET6 336 struct in6_addr last6, cur6, in6; 337 #endif 338 339 CARP_LOCK_ASSERT(sc); 340 341 /* Compute ipad from key. */ 342 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 343 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 344 for (i = 0; i < sizeof(sc->sc_pad); i++) 345 sc->sc_pad[i] ^= 0x36; 346 347 /* Precompute first part of inner hash. */ 348 SHA1Init(&sc->sc_sha1); 349 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 350 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 351 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 352 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 353 #ifdef INET 354 cur.s_addr = 0; 355 do { 356 found = 0; 357 last = cur; 358 cur.s_addr = 0xffffffff; 359 CARP_FOREACH_IFA(sc, ifa) { 360 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 361 if (ifa->ifa_addr->sa_family == AF_INET && 362 ntohl(in.s_addr) > ntohl(last.s_addr) && 363 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 364 cur.s_addr = in.s_addr; 365 found++; 366 } 367 } 368 if (found) 369 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 370 } while (found); 371 #endif /* INET */ 372 #ifdef INET6 373 memset(&cur6, 0, sizeof(cur6)); 374 do { 375 found = 0; 376 last6 = cur6; 377 memset(&cur6, 0xff, sizeof(cur6)); 378 CARP_FOREACH_IFA(sc, ifa) { 379 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 380 if (IN6_IS_SCOPE_EMBED(&in6)) 381 in6.s6_addr16[1] = 0; 382 if (ifa->ifa_addr->sa_family == AF_INET6 && 383 memcmp(&in6, &last6, sizeof(in6)) > 0 && 384 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 385 cur6 = in6; 386 found++; 387 } 388 } 389 if (found) 390 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 391 } while (found); 392 #endif /* INET6 */ 393 394 /* convert ipad to opad */ 395 for (i = 0; i < sizeof(sc->sc_pad); i++) 396 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 397 } 398 399 static void 400 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 401 unsigned char md[20]) 402 { 403 SHA1_CTX sha1ctx; 404 405 CARP_LOCK_ASSERT(sc); 406 407 /* fetch first half of inner hash */ 408 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 409 410 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 411 SHA1Final(md, &sha1ctx); 412 413 /* outer hash */ 414 SHA1Init(&sha1ctx); 415 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 416 SHA1Update(&sha1ctx, md, 20); 417 SHA1Final(md, &sha1ctx); 418 } 419 420 static int 421 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 422 unsigned char md[20]) 423 { 424 unsigned char md2[20]; 425 426 CARP_LOCK_ASSERT(sc); 427 428 carp_hmac_generate(sc, counter, md2); 429 430 return (bcmp(md, md2, sizeof(md2))); 431 } 432 433 /* 434 * process input packet. 435 * we have rearranged checks order compared to the rfc, 436 * but it seems more efficient this way or not possible otherwise. 437 */ 438 #ifdef INET 439 int 440 carp_input(struct mbuf **mp, int *offp, int proto) 441 { 442 struct mbuf *m = *mp; 443 struct ip *ip = mtod(m, struct ip *); 444 struct carp_header *ch; 445 int iplen, len; 446 447 iplen = *offp; 448 *mp = NULL; 449 450 CARPSTATS_INC(carps_ipackets); 451 452 if (!V_carp_allow) { 453 m_freem(m); 454 return (IPPROTO_DONE); 455 } 456 457 /* verify that the IP TTL is 255. */ 458 if (ip->ip_ttl != CARP_DFLTTL) { 459 CARPSTATS_INC(carps_badttl); 460 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 461 ip->ip_ttl, 462 m->m_pkthdr.rcvif->if_xname); 463 m_freem(m); 464 return (IPPROTO_DONE); 465 } 466 467 iplen = ip->ip_hl << 2; 468 469 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 470 CARPSTATS_INC(carps_badlen); 471 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 472 "on %s\n", __func__, m->m_len - sizeof(struct ip), 473 m->m_pkthdr.rcvif->if_xname); 474 m_freem(m); 475 return (IPPROTO_DONE); 476 } 477 478 if (iplen + sizeof(*ch) < m->m_len) { 479 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 480 CARPSTATS_INC(carps_hdrops); 481 CARP_DEBUG("%s: pullup failed\n", __func__); 482 return (IPPROTO_DONE); 483 } 484 ip = mtod(m, struct ip *); 485 } 486 ch = (struct carp_header *)((char *)ip + iplen); 487 488 /* 489 * verify that the received packet length is 490 * equal to the CARP header 491 */ 492 len = iplen + sizeof(*ch); 493 if (len > m->m_pkthdr.len) { 494 CARPSTATS_INC(carps_badlen); 495 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 496 m->m_pkthdr.len, 497 m->m_pkthdr.rcvif->if_xname); 498 m_freem(m); 499 return (IPPROTO_DONE); 500 } 501 502 if ((m = m_pullup(m, len)) == NULL) { 503 CARPSTATS_INC(carps_hdrops); 504 return (IPPROTO_DONE); 505 } 506 ip = mtod(m, struct ip *); 507 ch = (struct carp_header *)((char *)ip + iplen); 508 509 /* verify the CARP checksum */ 510 m->m_data += iplen; 511 if (in_cksum(m, len - iplen)) { 512 CARPSTATS_INC(carps_badsum); 513 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 514 m->m_pkthdr.rcvif->if_xname); 515 m_freem(m); 516 return (IPPROTO_DONE); 517 } 518 m->m_data -= iplen; 519 520 carp_input_c(m, ch, AF_INET); 521 return (IPPROTO_DONE); 522 } 523 #endif 524 525 #ifdef INET6 526 int 527 carp6_input(struct mbuf **mp, int *offp, int proto) 528 { 529 struct mbuf *m = *mp; 530 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 531 struct carp_header *ch; 532 u_int len; 533 534 CARPSTATS_INC(carps_ipackets6); 535 536 if (!V_carp_allow) { 537 m_freem(m); 538 return (IPPROTO_DONE); 539 } 540 541 /* check if received on a valid carp interface */ 542 if (m->m_pkthdr.rcvif->if_carp == NULL) { 543 CARPSTATS_INC(carps_badif); 544 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 545 __func__, m->m_pkthdr.rcvif->if_xname); 546 m_freem(m); 547 return (IPPROTO_DONE); 548 } 549 550 /* verify that the IP TTL is 255 */ 551 if (ip6->ip6_hlim != CARP_DFLTTL) { 552 CARPSTATS_INC(carps_badttl); 553 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 554 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 555 m_freem(m); 556 return (IPPROTO_DONE); 557 } 558 559 /* verify that we have a complete carp packet */ 560 len = m->m_len; 561 IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch)); 562 if (ch == NULL) { 563 CARPSTATS_INC(carps_badlen); 564 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 565 return (IPPROTO_DONE); 566 } 567 568 569 /* verify the CARP checksum */ 570 m->m_data += *offp; 571 if (in_cksum(m, sizeof(*ch))) { 572 CARPSTATS_INC(carps_badsum); 573 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 574 m->m_pkthdr.rcvif->if_xname); 575 m_freem(m); 576 return (IPPROTO_DONE); 577 } 578 m->m_data -= *offp; 579 580 carp_input_c(m, ch, AF_INET6); 581 return (IPPROTO_DONE); 582 } 583 #endif /* INET6 */ 584 585 /* 586 * This routine should not be necessary at all, but some switches 587 * (VMWare ESX vswitches) can echo our own packets back at us, 588 * and we must ignore them or they will cause us to drop out of 589 * MASTER mode. 590 * 591 * We cannot catch all cases of network loops. Instead, what we 592 * do here is catch any packet that arrives with a carp header 593 * with a VHID of 0, that comes from an address that is our own. 594 * These packets are by definition "from us" (even if they are from 595 * a misconfigured host that is pretending to be us). 596 * 597 * The VHID test is outside this mini-function. 598 */ 599 static int 600 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 601 { 602 #ifdef INET 603 struct ip *ip4; 604 struct in_addr in4; 605 #endif 606 #ifdef INET6 607 struct ip6_hdr *ip6; 608 struct in6_addr in6; 609 #endif 610 611 switch (af) { 612 #ifdef INET 613 case AF_INET: 614 ip4 = mtod(m, struct ip *); 615 in4 = ifatoia(ifa)->ia_addr.sin_addr; 616 return (in4.s_addr == ip4->ip_src.s_addr); 617 #endif 618 #ifdef INET6 619 case AF_INET6: 620 ip6 = mtod(m, struct ip6_hdr *); 621 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 622 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 623 #endif 624 default: 625 break; 626 } 627 return (0); 628 } 629 630 static void 631 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 632 { 633 struct ifnet *ifp = m->m_pkthdr.rcvif; 634 struct ifaddr *ifa, *match; 635 struct carp_softc *sc; 636 uint64_t tmp_counter; 637 struct timeval sc_tv, ch_tv; 638 int error; 639 640 /* 641 * Verify that the VHID is valid on the receiving interface. 642 * 643 * There should be just one match. If there are none 644 * the VHID is not valid and we drop the packet. If 645 * there are multiple VHID matches, take just the first 646 * one, for compatibility with previous code. While we're 647 * scanning, check for obvious loops in the network topology 648 * (these should never happen, and as noted above, we may 649 * miss real loops; this is just a double-check). 650 */ 651 IF_ADDR_RLOCK(ifp); 652 error = 0; 653 match = NULL; 654 IFNET_FOREACH_IFA(ifp, ifa) { 655 if (match == NULL && ifa->ifa_carp != NULL && 656 ifa->ifa_addr->sa_family == af && 657 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 658 match = ifa; 659 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 660 error = ELOOP; 661 } 662 ifa = error ? NULL : match; 663 if (ifa != NULL) 664 ifa_ref(ifa); 665 IF_ADDR_RUNLOCK(ifp); 666 667 if (ifa == NULL) { 668 if (error == ELOOP) { 669 CARP_DEBUG("dropping looped packet on interface %s\n", 670 ifp->if_xname); 671 CARPSTATS_INC(carps_badif); /* ??? */ 672 } else { 673 CARPSTATS_INC(carps_badvhid); 674 } 675 m_freem(m); 676 return; 677 } 678 679 /* verify the CARP version. */ 680 if (ch->carp_version != CARP_VERSION) { 681 CARPSTATS_INC(carps_badver); 682 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 683 ch->carp_version); 684 ifa_free(ifa); 685 m_freem(m); 686 return; 687 } 688 689 sc = ifa->ifa_carp; 690 CARP_LOCK(sc); 691 ifa_free(ifa); 692 693 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 694 CARPSTATS_INC(carps_badauth); 695 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 696 sc->sc_vhid, ifp->if_xname); 697 goto out; 698 } 699 700 tmp_counter = ntohl(ch->carp_counter[0]); 701 tmp_counter = tmp_counter<<32; 702 tmp_counter += ntohl(ch->carp_counter[1]); 703 704 /* XXX Replay protection goes here */ 705 706 sc->sc_init_counter = 0; 707 sc->sc_counter = tmp_counter; 708 709 sc_tv.tv_sec = sc->sc_advbase; 710 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 711 ch_tv.tv_sec = ch->carp_advbase; 712 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 713 714 switch (sc->sc_state) { 715 case INIT: 716 break; 717 case MASTER: 718 /* 719 * If we receive an advertisement from a master who's going to 720 * be more frequent than us, go into BACKUP state. 721 */ 722 if (timevalcmp(&sc_tv, &ch_tv, >) || 723 timevalcmp(&sc_tv, &ch_tv, ==)) { 724 callout_stop(&sc->sc_ad_tmo); 725 carp_set_state(sc, BACKUP, 726 "more frequent advertisement received"); 727 carp_setrun(sc, 0); 728 carp_delroute(sc); 729 } 730 break; 731 case BACKUP: 732 /* 733 * If we're pre-empting masters who advertise slower than us, 734 * and this one claims to be slower, treat him as down. 735 */ 736 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 737 carp_master_down_locked(sc, 738 "preempting a slower master"); 739 break; 740 } 741 742 /* 743 * If the master is going to advertise at such a low frequency 744 * that he's guaranteed to time out, we'd might as well just 745 * treat him as timed out now. 746 */ 747 sc_tv.tv_sec = sc->sc_advbase * 3; 748 if (timevalcmp(&sc_tv, &ch_tv, <)) { 749 carp_master_down_locked(sc, "master will time out"); 750 break; 751 } 752 753 /* 754 * Otherwise, we reset the counter and wait for the next 755 * advertisement. 756 */ 757 carp_setrun(sc, af); 758 break; 759 } 760 761 out: 762 CARP_UNLOCK(sc); 763 m_freem(m); 764 } 765 766 static int 767 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 768 { 769 struct m_tag *mtag; 770 771 if (sc->sc_init_counter) { 772 /* this could also be seconds since unix epoch */ 773 sc->sc_counter = arc4random(); 774 sc->sc_counter = sc->sc_counter << 32; 775 sc->sc_counter += arc4random(); 776 } else 777 sc->sc_counter++; 778 779 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 780 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 781 782 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 783 784 /* Tag packet for carp_output */ 785 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 786 M_NOWAIT)) == NULL) { 787 m_freem(m); 788 CARPSTATS_INC(carps_onomem); 789 return (ENOMEM); 790 } 791 bcopy(&sc, mtag + 1, sizeof(sc)); 792 m_tag_prepend(m, mtag); 793 794 return (0); 795 } 796 797 /* 798 * To avoid LORs and possible recursions this function shouldn't 799 * be called directly, but scheduled via taskqueue. 800 */ 801 static void 802 carp_send_ad_all(void *ctx __unused, int pending __unused) 803 { 804 struct carp_softc *sc; 805 806 mtx_lock(&carp_mtx); 807 LIST_FOREACH(sc, &carp_list, sc_next) 808 if (sc->sc_state == MASTER) { 809 CARP_LOCK(sc); 810 CURVNET_SET(sc->sc_carpdev->if_vnet); 811 carp_send_ad_locked(sc); 812 CURVNET_RESTORE(); 813 CARP_UNLOCK(sc); 814 } 815 mtx_unlock(&carp_mtx); 816 } 817 818 /* Send a periodic advertisement, executed in callout context. */ 819 static void 820 carp_send_ad(void *v) 821 { 822 struct carp_softc *sc = v; 823 824 CARP_LOCK_ASSERT(sc); 825 CURVNET_SET(sc->sc_carpdev->if_vnet); 826 carp_send_ad_locked(sc); 827 CURVNET_RESTORE(); 828 CARP_UNLOCK(sc); 829 } 830 831 static void 832 carp_send_ad_error(struct carp_softc *sc, int error) 833 { 834 835 if (error) { 836 if (sc->sc_sendad_errors < INT_MAX) 837 sc->sc_sendad_errors++; 838 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 839 static const char fmt[] = "send error %d on %s"; 840 char msg[sizeof(fmt) + IFNAMSIZ]; 841 842 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 843 carp_demote_adj(V_carp_senderr_adj, msg); 844 } 845 sc->sc_sendad_success = 0; 846 } else { 847 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && 848 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 849 static const char fmt[] = "send ok on %s"; 850 char msg[sizeof(fmt) + IFNAMSIZ]; 851 852 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 853 carp_demote_adj(-V_carp_senderr_adj, msg); 854 sc->sc_sendad_errors = 0; 855 } else 856 sc->sc_sendad_errors = 0; 857 } 858 } 859 860 /* 861 * Pick the best ifaddr on the given ifp for sending CARP 862 * advertisements. 863 * 864 * "Best" here is defined by ifa_preferred(). This function is much 865 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 866 * 867 * (This could be simplified to return the actual address, except that 868 * it has a different format in AF_INET and AF_INET6.) 869 */ 870 static struct ifaddr * 871 carp_best_ifa(int af, struct ifnet *ifp) 872 { 873 struct ifaddr *ifa, *best; 874 875 if (af >= AF_MAX) 876 return (NULL); 877 best = NULL; 878 IF_ADDR_RLOCK(ifp); 879 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 880 if (ifa->ifa_addr->sa_family == af && 881 (best == NULL || ifa_preferred(best, ifa))) 882 best = ifa; 883 } 884 IF_ADDR_RUNLOCK(ifp); 885 if (best != NULL) 886 ifa_ref(best); 887 return (best); 888 } 889 890 static void 891 carp_send_ad_locked(struct carp_softc *sc) 892 { 893 struct carp_header ch; 894 struct timeval tv; 895 struct ifaddr *ifa; 896 struct carp_header *ch_ptr; 897 struct mbuf *m; 898 int len, advskew; 899 900 CARP_LOCK_ASSERT(sc); 901 902 advskew = DEMOTE_ADVSKEW(sc); 903 tv.tv_sec = sc->sc_advbase; 904 tv.tv_usec = advskew * 1000000 / 256; 905 906 ch.carp_version = CARP_VERSION; 907 ch.carp_type = CARP_ADVERTISEMENT; 908 ch.carp_vhid = sc->sc_vhid; 909 ch.carp_advbase = sc->sc_advbase; 910 ch.carp_advskew = advskew; 911 ch.carp_authlen = 7; /* XXX DEFINE */ 912 ch.carp_pad1 = 0; /* must be zero */ 913 ch.carp_cksum = 0; 914 915 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 916 917 #ifdef INET 918 if (sc->sc_naddrs) { 919 struct ip *ip; 920 921 m = m_gethdr(M_NOWAIT, MT_DATA); 922 if (m == NULL) { 923 CARPSTATS_INC(carps_onomem); 924 goto resched; 925 } 926 len = sizeof(*ip) + sizeof(ch); 927 m->m_pkthdr.len = len; 928 m->m_pkthdr.rcvif = NULL; 929 m->m_len = len; 930 M_ALIGN(m, m->m_len); 931 m->m_flags |= M_MCAST; 932 ip = mtod(m, struct ip *); 933 ip->ip_v = IPVERSION; 934 ip->ip_hl = sizeof(*ip) >> 2; 935 ip->ip_tos = IPTOS_LOWDELAY; 936 ip->ip_len = htons(len); 937 ip->ip_off = htons(IP_DF); 938 ip->ip_ttl = CARP_DFLTTL; 939 ip->ip_p = IPPROTO_CARP; 940 ip->ip_sum = 0; 941 ip_fillid(ip); 942 943 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 944 if (ifa != NULL) { 945 ip->ip_src.s_addr = 946 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 947 ifa_free(ifa); 948 } else 949 ip->ip_src.s_addr = 0; 950 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 951 952 ch_ptr = (struct carp_header *)(&ip[1]); 953 bcopy(&ch, ch_ptr, sizeof(ch)); 954 if (carp_prepare_ad(m, sc, ch_ptr)) 955 goto resched; 956 957 m->m_data += sizeof(*ip); 958 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 959 m->m_data -= sizeof(*ip); 960 961 CARPSTATS_INC(carps_opackets); 962 963 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 964 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 965 } 966 #endif /* INET */ 967 #ifdef INET6 968 if (sc->sc_naddrs6) { 969 struct ip6_hdr *ip6; 970 971 m = m_gethdr(M_NOWAIT, MT_DATA); 972 if (m == NULL) { 973 CARPSTATS_INC(carps_onomem); 974 goto resched; 975 } 976 len = sizeof(*ip6) + sizeof(ch); 977 m->m_pkthdr.len = len; 978 m->m_pkthdr.rcvif = NULL; 979 m->m_len = len; 980 M_ALIGN(m, m->m_len); 981 m->m_flags |= M_MCAST; 982 ip6 = mtod(m, struct ip6_hdr *); 983 bzero(ip6, sizeof(*ip6)); 984 ip6->ip6_vfc |= IPV6_VERSION; 985 ip6->ip6_hlim = CARP_DFLTTL; 986 ip6->ip6_nxt = IPPROTO_CARP; 987 988 /* set the source address */ 989 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 990 if (ifa != NULL) { 991 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 992 sizeof(struct in6_addr)); 993 ifa_free(ifa); 994 } else 995 /* This should never happen with IPv6. */ 996 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 997 998 /* Set the multicast destination. */ 999 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1000 ip6->ip6_dst.s6_addr8[15] = 0x12; 1001 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1002 m_freem(m); 1003 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1004 goto resched; 1005 } 1006 1007 ch_ptr = (struct carp_header *)(&ip6[1]); 1008 bcopy(&ch, ch_ptr, sizeof(ch)); 1009 if (carp_prepare_ad(m, sc, ch_ptr)) 1010 goto resched; 1011 1012 m->m_data += sizeof(*ip6); 1013 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1014 m->m_data -= sizeof(*ip6); 1015 1016 CARPSTATS_INC(carps_opackets6); 1017 1018 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1019 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1020 } 1021 #endif /* INET6 */ 1022 1023 resched: 1024 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1025 } 1026 1027 static void 1028 carp_addroute(struct carp_softc *sc) 1029 { 1030 struct ifaddr *ifa; 1031 1032 CARP_FOREACH_IFA(sc, ifa) 1033 carp_ifa_addroute(ifa); 1034 } 1035 1036 static void 1037 carp_ifa_addroute(struct ifaddr *ifa) 1038 { 1039 1040 switch (ifa->ifa_addr->sa_family) { 1041 #ifdef INET 1042 case AF_INET: 1043 in_addprefix(ifatoia(ifa), RTF_UP); 1044 ifa_add_loopback_route(ifa, 1045 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1046 break; 1047 #endif 1048 #ifdef INET6 1049 case AF_INET6: 1050 ifa_add_loopback_route(ifa, 1051 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1052 nd6_add_ifa_lle(ifatoia6(ifa)); 1053 break; 1054 #endif 1055 } 1056 } 1057 1058 static void 1059 carp_delroute(struct carp_softc *sc) 1060 { 1061 struct ifaddr *ifa; 1062 1063 CARP_FOREACH_IFA(sc, ifa) 1064 carp_ifa_delroute(ifa); 1065 } 1066 1067 static void 1068 carp_ifa_delroute(struct ifaddr *ifa) 1069 { 1070 1071 switch (ifa->ifa_addr->sa_family) { 1072 #ifdef INET 1073 case AF_INET: 1074 ifa_del_loopback_route(ifa, 1075 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1076 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1077 break; 1078 #endif 1079 #ifdef INET6 1080 case AF_INET6: 1081 ifa_del_loopback_route(ifa, 1082 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1083 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1084 break; 1085 #endif 1086 } 1087 } 1088 1089 int 1090 carp_master(struct ifaddr *ifa) 1091 { 1092 struct carp_softc *sc = ifa->ifa_carp; 1093 1094 return (sc->sc_state == MASTER); 1095 } 1096 1097 #ifdef INET 1098 /* 1099 * Broadcast a gratuitous ARP request containing 1100 * the virtual router MAC address for each IP address 1101 * associated with the virtual router. 1102 */ 1103 static void 1104 carp_send_arp(struct carp_softc *sc) 1105 { 1106 struct ifaddr *ifa; 1107 struct in_addr addr; 1108 1109 CARP_FOREACH_IFA(sc, ifa) { 1110 if (ifa->ifa_addr->sa_family != AF_INET) 1111 continue; 1112 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1113 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1114 } 1115 } 1116 1117 int 1118 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1119 { 1120 struct carp_softc *sc = ifa->ifa_carp; 1121 1122 if (sc->sc_state == MASTER) { 1123 *enaddr = LLADDR(&sc->sc_addr); 1124 return (1); 1125 } 1126 1127 return (0); 1128 } 1129 #endif 1130 1131 #ifdef INET6 1132 static void 1133 carp_send_na(struct carp_softc *sc) 1134 { 1135 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1136 struct ifaddr *ifa; 1137 struct in6_addr *in6; 1138 1139 CARP_FOREACH_IFA(sc, ifa) { 1140 if (ifa->ifa_addr->sa_family != AF_INET6) 1141 continue; 1142 1143 in6 = IFA_IN6(ifa); 1144 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1145 ND_NA_FLAG_OVERRIDE, 1, NULL); 1146 DELAY(1000); /* XXX */ 1147 } 1148 } 1149 1150 /* 1151 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1152 * matches and is not a carp address. Returns NULL otherwise. 1153 */ 1154 struct ifaddr * 1155 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1156 { 1157 struct ifaddr *ifa; 1158 1159 ifa = NULL; 1160 IF_ADDR_RLOCK(ifp); 1161 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1162 if (ifa->ifa_addr->sa_family != AF_INET6) 1163 continue; 1164 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1165 continue; 1166 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1167 ifa = NULL; 1168 else 1169 ifa_ref(ifa); 1170 break; 1171 } 1172 IF_ADDR_RUNLOCK(ifp); 1173 1174 return (ifa); 1175 } 1176 1177 caddr_t 1178 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1179 { 1180 struct ifaddr *ifa; 1181 1182 IF_ADDR_RLOCK(ifp); 1183 IFNET_FOREACH_IFA(ifp, ifa) 1184 if (ifa->ifa_addr->sa_family == AF_INET6 && 1185 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1186 struct carp_softc *sc = ifa->ifa_carp; 1187 struct m_tag *mtag; 1188 1189 IF_ADDR_RUNLOCK(ifp); 1190 1191 mtag = m_tag_get(PACKET_TAG_CARP, 1192 sizeof(struct carp_softc *), M_NOWAIT); 1193 if (mtag == NULL) 1194 /* Better a bit than nothing. */ 1195 return (LLADDR(&sc->sc_addr)); 1196 1197 bcopy(&sc, mtag + 1, sizeof(sc)); 1198 m_tag_prepend(m, mtag); 1199 1200 return (LLADDR(&sc->sc_addr)); 1201 } 1202 IF_ADDR_RUNLOCK(ifp); 1203 1204 return (NULL); 1205 } 1206 #endif /* INET6 */ 1207 1208 int 1209 carp_forus(struct ifnet *ifp, u_char *dhost) 1210 { 1211 struct carp_softc *sc; 1212 uint8_t *ena = dhost; 1213 1214 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1215 return (0); 1216 1217 CIF_LOCK(ifp->if_carp); 1218 IFNET_FOREACH_CARP(ifp, sc) { 1219 CARP_LOCK(sc); 1220 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1221 ETHER_ADDR_LEN)) { 1222 CARP_UNLOCK(sc); 1223 CIF_UNLOCK(ifp->if_carp); 1224 return (1); 1225 } 1226 CARP_UNLOCK(sc); 1227 } 1228 CIF_UNLOCK(ifp->if_carp); 1229 1230 return (0); 1231 } 1232 1233 /* Master down timeout event, executed in callout context. */ 1234 static void 1235 carp_master_down(void *v) 1236 { 1237 struct carp_softc *sc = v; 1238 1239 CARP_LOCK_ASSERT(sc); 1240 1241 CURVNET_SET(sc->sc_carpdev->if_vnet); 1242 if (sc->sc_state == BACKUP) { 1243 carp_master_down_locked(sc, "master timed out"); 1244 } 1245 CURVNET_RESTORE(); 1246 1247 CARP_UNLOCK(sc); 1248 } 1249 1250 static void 1251 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1252 { 1253 1254 CARP_LOCK_ASSERT(sc); 1255 1256 switch (sc->sc_state) { 1257 case BACKUP: 1258 carp_set_state(sc, MASTER, reason); 1259 carp_send_ad_locked(sc); 1260 #ifdef INET 1261 carp_send_arp(sc); 1262 #endif 1263 #ifdef INET6 1264 carp_send_na(sc); 1265 #endif 1266 carp_setrun(sc, 0); 1267 carp_addroute(sc); 1268 break; 1269 case INIT: 1270 case MASTER: 1271 #ifdef INVARIANTS 1272 panic("carp: VHID %u@%s: master_down event in %s state\n", 1273 sc->sc_vhid, 1274 sc->sc_carpdev->if_xname, 1275 sc->sc_state ? "MASTER" : "INIT"); 1276 #endif 1277 break; 1278 } 1279 } 1280 1281 /* 1282 * When in backup state, af indicates whether to reset the master down timer 1283 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1284 */ 1285 static void 1286 carp_setrun(struct carp_softc *sc, sa_family_t af) 1287 { 1288 struct timeval tv; 1289 1290 CARP_LOCK_ASSERT(sc); 1291 1292 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1293 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1294 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0)) 1295 return; 1296 1297 switch (sc->sc_state) { 1298 case INIT: 1299 carp_set_state(sc, BACKUP, "initialization complete"); 1300 carp_setrun(sc, 0); 1301 break; 1302 case BACKUP: 1303 callout_stop(&sc->sc_ad_tmo); 1304 tv.tv_sec = 3 * sc->sc_advbase; 1305 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1306 switch (af) { 1307 #ifdef INET 1308 case AF_INET: 1309 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1310 carp_master_down, sc); 1311 break; 1312 #endif 1313 #ifdef INET6 1314 case AF_INET6: 1315 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1316 carp_master_down, sc); 1317 break; 1318 #endif 1319 default: 1320 #ifdef INET 1321 if (sc->sc_naddrs) 1322 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1323 carp_master_down, sc); 1324 #endif 1325 #ifdef INET6 1326 if (sc->sc_naddrs6) 1327 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1328 carp_master_down, sc); 1329 #endif 1330 break; 1331 } 1332 break; 1333 case MASTER: 1334 tv.tv_sec = sc->sc_advbase; 1335 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1336 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1337 carp_send_ad, sc); 1338 break; 1339 } 1340 } 1341 1342 /* 1343 * Setup multicast structures. 1344 */ 1345 static int 1346 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1347 { 1348 struct ifnet *ifp = cif->cif_ifp; 1349 int error = 0; 1350 1351 switch (sa) { 1352 #ifdef INET 1353 case AF_INET: 1354 { 1355 struct ip_moptions *imo = &cif->cif_imo; 1356 struct in_addr addr; 1357 1358 if (imo->imo_membership) 1359 return (0); 1360 1361 imo->imo_membership = (struct in_multi **)malloc( 1362 (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, 1363 M_WAITOK); 1364 imo->imo_mfilters = NULL; 1365 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS; 1366 imo->imo_multicast_vif = -1; 1367 1368 addr.s_addr = htonl(INADDR_CARP_GROUP); 1369 if ((error = in_joingroup(ifp, &addr, NULL, 1370 &imo->imo_membership[0])) != 0) { 1371 free(imo->imo_membership, M_CARP); 1372 break; 1373 } 1374 imo->imo_num_memberships++; 1375 imo->imo_multicast_ifp = ifp; 1376 imo->imo_multicast_ttl = CARP_DFLTTL; 1377 imo->imo_multicast_loop = 0; 1378 break; 1379 } 1380 #endif 1381 #ifdef INET6 1382 case AF_INET6: 1383 { 1384 struct ip6_moptions *im6o = &cif->cif_im6o; 1385 struct in6_addr in6; 1386 struct in6_multi *in6m; 1387 1388 if (im6o->im6o_membership) 1389 return (0); 1390 1391 im6o->im6o_membership = (struct in6_multi **)malloc( 1392 (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, 1393 M_ZERO | M_WAITOK); 1394 im6o->im6o_mfilters = NULL; 1395 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; 1396 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1397 im6o->im6o_multicast_ifp = ifp; 1398 1399 /* Join IPv6 CARP multicast group. */ 1400 bzero(&in6, sizeof(in6)); 1401 in6.s6_addr16[0] = htons(0xff02); 1402 in6.s6_addr8[15] = 0x12; 1403 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1404 free(im6o->im6o_membership, M_CARP); 1405 break; 1406 } 1407 in6m = NULL; 1408 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { 1409 free(im6o->im6o_membership, M_CARP); 1410 break; 1411 } 1412 im6o->im6o_membership[0] = in6m; 1413 im6o->im6o_num_memberships++; 1414 1415 /* Join solicited multicast address. */ 1416 bzero(&in6, sizeof(in6)); 1417 in6.s6_addr16[0] = htons(0xff02); 1418 in6.s6_addr32[1] = 0; 1419 in6.s6_addr32[2] = htonl(1); 1420 in6.s6_addr32[3] = 0; 1421 in6.s6_addr8[12] = 0xff; 1422 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1423 in6_mc_leave(im6o->im6o_membership[0], NULL); 1424 free(im6o->im6o_membership, M_CARP); 1425 break; 1426 } 1427 in6m = NULL; 1428 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { 1429 in6_mc_leave(im6o->im6o_membership[0], NULL); 1430 free(im6o->im6o_membership, M_CARP); 1431 break; 1432 } 1433 im6o->im6o_membership[1] = in6m; 1434 im6o->im6o_num_memberships++; 1435 break; 1436 } 1437 #endif 1438 } 1439 1440 return (error); 1441 } 1442 1443 /* 1444 * Free multicast structures. 1445 */ 1446 static void 1447 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1448 { 1449 1450 sx_assert(&carp_sx, SA_XLOCKED); 1451 1452 switch (sa) { 1453 #ifdef INET 1454 case AF_INET: 1455 if (cif->cif_naddrs == 0) { 1456 struct ip_moptions *imo = &cif->cif_imo; 1457 1458 in_leavegroup(imo->imo_membership[0], NULL); 1459 KASSERT(imo->imo_mfilters == NULL, 1460 ("%s: imo_mfilters != NULL", __func__)); 1461 free(imo->imo_membership, M_CARP); 1462 imo->imo_membership = NULL; 1463 1464 } 1465 break; 1466 #endif 1467 #ifdef INET6 1468 case AF_INET6: 1469 if (cif->cif_naddrs6 == 0) { 1470 struct ip6_moptions *im6o = &cif->cif_im6o; 1471 1472 in6_mc_leave(im6o->im6o_membership[0], NULL); 1473 in6_mc_leave(im6o->im6o_membership[1], NULL); 1474 KASSERT(im6o->im6o_mfilters == NULL, 1475 ("%s: im6o_mfilters != NULL", __func__)); 1476 free(im6o->im6o_membership, M_CARP); 1477 im6o->im6o_membership = NULL; 1478 } 1479 break; 1480 #endif 1481 } 1482 } 1483 1484 int 1485 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1486 { 1487 struct m_tag *mtag; 1488 struct carp_softc *sc; 1489 1490 if (!sa) 1491 return (0); 1492 1493 switch (sa->sa_family) { 1494 #ifdef INET 1495 case AF_INET: 1496 break; 1497 #endif 1498 #ifdef INET6 1499 case AF_INET6: 1500 break; 1501 #endif 1502 default: 1503 return (0); 1504 } 1505 1506 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1507 if (mtag == NULL) 1508 return (0); 1509 1510 bcopy(mtag + 1, &sc, sizeof(sc)); 1511 1512 /* Set the source MAC address to the Virtual Router MAC Address. */ 1513 switch (ifp->if_type) { 1514 case IFT_ETHER: 1515 case IFT_BRIDGE: 1516 case IFT_L2VLAN: { 1517 struct ether_header *eh; 1518 1519 eh = mtod(m, struct ether_header *); 1520 eh->ether_shost[0] = 0; 1521 eh->ether_shost[1] = 0; 1522 eh->ether_shost[2] = 0x5e; 1523 eh->ether_shost[3] = 0; 1524 eh->ether_shost[4] = 1; 1525 eh->ether_shost[5] = sc->sc_vhid; 1526 } 1527 break; 1528 case IFT_FDDI: { 1529 struct fddi_header *fh; 1530 1531 fh = mtod(m, struct fddi_header *); 1532 fh->fddi_shost[0] = 0; 1533 fh->fddi_shost[1] = 0; 1534 fh->fddi_shost[2] = 0x5e; 1535 fh->fddi_shost[3] = 0; 1536 fh->fddi_shost[4] = 1; 1537 fh->fddi_shost[5] = sc->sc_vhid; 1538 } 1539 break; 1540 case IFT_ISO88025: { 1541 struct iso88025_header *th; 1542 th = mtod(m, struct iso88025_header *); 1543 th->iso88025_shost[0] = 3; 1544 th->iso88025_shost[1] = 0; 1545 th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1); 1546 th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1); 1547 th->iso88025_shost[4] = 0; 1548 th->iso88025_shost[5] = 0; 1549 } 1550 break; 1551 default: 1552 printf("%s: carp is not supported for the %d interface type\n", 1553 ifp->if_xname, ifp->if_type); 1554 return (EOPNOTSUPP); 1555 } 1556 1557 return (0); 1558 } 1559 1560 static struct carp_softc* 1561 carp_alloc(struct ifnet *ifp) 1562 { 1563 struct carp_softc *sc; 1564 struct carp_if *cif; 1565 1566 sx_assert(&carp_sx, SA_XLOCKED); 1567 1568 if ((cif = ifp->if_carp) == NULL) 1569 cif = carp_alloc_if(ifp); 1570 1571 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1572 1573 sc->sc_advbase = CARP_DFLTINTV; 1574 sc->sc_vhid = -1; /* required setting */ 1575 sc->sc_init_counter = 1; 1576 sc->sc_state = INIT; 1577 1578 sc->sc_ifasiz = sizeof(struct ifaddr *); 1579 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1580 sc->sc_carpdev = ifp; 1581 1582 CARP_LOCK_INIT(sc); 1583 #ifdef INET 1584 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1585 #endif 1586 #ifdef INET6 1587 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1588 #endif 1589 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1590 1591 CIF_LOCK(cif); 1592 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1593 CIF_UNLOCK(cif); 1594 1595 mtx_lock(&carp_mtx); 1596 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1597 mtx_unlock(&carp_mtx); 1598 1599 return (sc); 1600 } 1601 1602 static void 1603 carp_grow_ifas(struct carp_softc *sc) 1604 { 1605 struct ifaddr **new; 1606 1607 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1608 CARP_LOCK(sc); 1609 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1610 free(sc->sc_ifas, M_CARP); 1611 sc->sc_ifas = new; 1612 sc->sc_ifasiz *= 2; 1613 CARP_UNLOCK(sc); 1614 } 1615 1616 static void 1617 carp_destroy(struct carp_softc *sc) 1618 { 1619 struct ifnet *ifp = sc->sc_carpdev; 1620 struct carp_if *cif = ifp->if_carp; 1621 1622 sx_assert(&carp_sx, SA_XLOCKED); 1623 1624 if (sc->sc_suppress) 1625 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1626 CARP_UNLOCK(sc); 1627 1628 CIF_LOCK(cif); 1629 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1630 CIF_UNLOCK(cif); 1631 1632 mtx_lock(&carp_mtx); 1633 LIST_REMOVE(sc, sc_next); 1634 mtx_unlock(&carp_mtx); 1635 1636 callout_drain(&sc->sc_ad_tmo); 1637 #ifdef INET 1638 callout_drain(&sc->sc_md_tmo); 1639 #endif 1640 #ifdef INET6 1641 callout_drain(&sc->sc_md6_tmo); 1642 #endif 1643 CARP_LOCK_DESTROY(sc); 1644 1645 free(sc->sc_ifas, M_CARP); 1646 free(sc, M_CARP); 1647 } 1648 1649 static struct carp_if* 1650 carp_alloc_if(struct ifnet *ifp) 1651 { 1652 struct carp_if *cif; 1653 int error; 1654 1655 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1656 1657 if ((error = ifpromisc(ifp, 1)) != 0) 1658 printf("%s: ifpromisc(%s) failed: %d\n", 1659 __func__, ifp->if_xname, error); 1660 else 1661 cif->cif_flags |= CIF_PROMISC; 1662 1663 CIF_LOCK_INIT(cif); 1664 cif->cif_ifp = ifp; 1665 TAILQ_INIT(&cif->cif_vrs); 1666 1667 IF_ADDR_WLOCK(ifp); 1668 ifp->if_carp = cif; 1669 if_ref(ifp); 1670 IF_ADDR_WUNLOCK(ifp); 1671 1672 return (cif); 1673 } 1674 1675 static void 1676 carp_free_if(struct carp_if *cif) 1677 { 1678 struct ifnet *ifp = cif->cif_ifp; 1679 1680 CIF_LOCK_ASSERT(cif); 1681 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1682 __func__)); 1683 1684 IF_ADDR_WLOCK(ifp); 1685 ifp->if_carp = NULL; 1686 IF_ADDR_WUNLOCK(ifp); 1687 1688 CIF_LOCK_DESTROY(cif); 1689 1690 if (cif->cif_flags & CIF_PROMISC) 1691 ifpromisc(ifp, 0); 1692 if_rele(ifp); 1693 1694 free(cif, M_CARP); 1695 } 1696 1697 static void 1698 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1699 { 1700 1701 CARP_LOCK(sc); 1702 carpr->carpr_state = sc->sc_state; 1703 carpr->carpr_vhid = sc->sc_vhid; 1704 carpr->carpr_advbase = sc->sc_advbase; 1705 carpr->carpr_advskew = sc->sc_advskew; 1706 if (priv) 1707 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1708 else 1709 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1710 CARP_UNLOCK(sc); 1711 } 1712 1713 int 1714 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1715 { 1716 struct carpreq carpr; 1717 struct ifnet *ifp; 1718 struct carp_softc *sc = NULL; 1719 int error = 0, locked = 0; 1720 1721 if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr))) 1722 return (error); 1723 1724 ifp = ifunit_ref(ifr->ifr_name); 1725 if (ifp == NULL) 1726 return (ENXIO); 1727 1728 switch (ifp->if_type) { 1729 case IFT_ETHER: 1730 case IFT_L2VLAN: 1731 case IFT_BRIDGE: 1732 case IFT_FDDI: 1733 case IFT_ISO88025: 1734 break; 1735 default: 1736 error = EOPNOTSUPP; 1737 goto out; 1738 } 1739 1740 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1741 error = EADDRNOTAVAIL; 1742 goto out; 1743 } 1744 1745 sx_xlock(&carp_sx); 1746 switch (cmd) { 1747 case SIOCSVH: 1748 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1749 break; 1750 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1751 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1752 error = EINVAL; 1753 break; 1754 } 1755 1756 if (ifp->if_carp) { 1757 IFNET_FOREACH_CARP(ifp, sc) 1758 if (sc->sc_vhid == carpr.carpr_vhid) 1759 break; 1760 } 1761 if (sc == NULL) { 1762 sc = carp_alloc(ifp); 1763 CARP_LOCK(sc); 1764 sc->sc_vhid = carpr.carpr_vhid; 1765 LLADDR(&sc->sc_addr)[0] = 0; 1766 LLADDR(&sc->sc_addr)[1] = 0; 1767 LLADDR(&sc->sc_addr)[2] = 0x5e; 1768 LLADDR(&sc->sc_addr)[3] = 0; 1769 LLADDR(&sc->sc_addr)[4] = 1; 1770 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1771 } else 1772 CARP_LOCK(sc); 1773 locked = 1; 1774 if (carpr.carpr_advbase > 0) { 1775 if (carpr.carpr_advbase > 255 || 1776 carpr.carpr_advbase < CARP_DFLTINTV) { 1777 error = EINVAL; 1778 break; 1779 } 1780 sc->sc_advbase = carpr.carpr_advbase; 1781 } 1782 if (carpr.carpr_advskew >= 255) { 1783 error = EINVAL; 1784 break; 1785 } 1786 sc->sc_advskew = carpr.carpr_advskew; 1787 if (carpr.carpr_key[0] != '\0') { 1788 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1789 carp_hmac_prepare(sc); 1790 } 1791 if (sc->sc_state != INIT && 1792 carpr.carpr_state != sc->sc_state) { 1793 switch (carpr.carpr_state) { 1794 case BACKUP: 1795 callout_stop(&sc->sc_ad_tmo); 1796 carp_set_state(sc, BACKUP, 1797 "user requested via ifconfig"); 1798 carp_setrun(sc, 0); 1799 carp_delroute(sc); 1800 break; 1801 case MASTER: 1802 carp_master_down_locked(sc, 1803 "user requested via ifconfig"); 1804 break; 1805 default: 1806 break; 1807 } 1808 } 1809 break; 1810 1811 case SIOCGVH: 1812 { 1813 int priveleged; 1814 1815 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1816 error = EINVAL; 1817 break; 1818 } 1819 if (carpr.carpr_count < 1) { 1820 error = EMSGSIZE; 1821 break; 1822 } 1823 if (ifp->if_carp == NULL) { 1824 error = ENOENT; 1825 break; 1826 } 1827 1828 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1829 if (carpr.carpr_vhid != 0) { 1830 IFNET_FOREACH_CARP(ifp, sc) 1831 if (sc->sc_vhid == carpr.carpr_vhid) 1832 break; 1833 if (sc == NULL) { 1834 error = ENOENT; 1835 break; 1836 } 1837 carp_carprcp(&carpr, sc, priveleged); 1838 error = copyout(&carpr, ifr->ifr_data, sizeof(carpr)); 1839 } else { 1840 int i, count; 1841 1842 count = 0; 1843 IFNET_FOREACH_CARP(ifp, sc) 1844 count++; 1845 1846 if (count > carpr.carpr_count) { 1847 CIF_UNLOCK(ifp->if_carp); 1848 error = EMSGSIZE; 1849 break; 1850 } 1851 1852 i = 0; 1853 IFNET_FOREACH_CARP(ifp, sc) { 1854 carp_carprcp(&carpr, sc, priveleged); 1855 carpr.carpr_count = count; 1856 error = copyout(&carpr, ifr->ifr_data + 1857 (i * sizeof(carpr)), sizeof(carpr)); 1858 if (error) { 1859 CIF_UNLOCK(ifp->if_carp); 1860 break; 1861 } 1862 i++; 1863 } 1864 } 1865 break; 1866 } 1867 default: 1868 error = EINVAL; 1869 } 1870 sx_xunlock(&carp_sx); 1871 1872 out: 1873 if (locked) 1874 CARP_UNLOCK(sc); 1875 if_rele(ifp); 1876 1877 return (error); 1878 } 1879 1880 static int 1881 carp_get_vhid(struct ifaddr *ifa) 1882 { 1883 1884 if (ifa == NULL || ifa->ifa_carp == NULL) 1885 return (0); 1886 1887 return (ifa->ifa_carp->sc_vhid); 1888 } 1889 1890 int 1891 carp_attach(struct ifaddr *ifa, int vhid) 1892 { 1893 struct ifnet *ifp = ifa->ifa_ifp; 1894 struct carp_if *cif = ifp->if_carp; 1895 struct carp_softc *sc; 1896 int index, error; 1897 1898 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1899 1900 switch (ifa->ifa_addr->sa_family) { 1901 #ifdef INET 1902 case AF_INET: 1903 #endif 1904 #ifdef INET6 1905 case AF_INET6: 1906 #endif 1907 break; 1908 default: 1909 return (EPROTOTYPE); 1910 } 1911 1912 sx_xlock(&carp_sx); 1913 if (ifp->if_carp == NULL) { 1914 sx_xunlock(&carp_sx); 1915 return (ENOPROTOOPT); 1916 } 1917 1918 IFNET_FOREACH_CARP(ifp, sc) 1919 if (sc->sc_vhid == vhid) 1920 break; 1921 if (sc == NULL) { 1922 sx_xunlock(&carp_sx); 1923 return (ENOENT); 1924 } 1925 1926 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1927 if (error) { 1928 CIF_FREE(cif); 1929 sx_xunlock(&carp_sx); 1930 return (error); 1931 } 1932 1933 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1934 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1935 carp_grow_ifas(sc); 1936 1937 switch (ifa->ifa_addr->sa_family) { 1938 #ifdef INET 1939 case AF_INET: 1940 cif->cif_naddrs++; 1941 sc->sc_naddrs++; 1942 break; 1943 #endif 1944 #ifdef INET6 1945 case AF_INET6: 1946 cif->cif_naddrs6++; 1947 sc->sc_naddrs6++; 1948 break; 1949 #endif 1950 } 1951 1952 ifa_ref(ifa); 1953 1954 CARP_LOCK(sc); 1955 sc->sc_ifas[index - 1] = ifa; 1956 ifa->ifa_carp = sc; 1957 carp_hmac_prepare(sc); 1958 carp_sc_state(sc); 1959 CARP_UNLOCK(sc); 1960 1961 sx_xunlock(&carp_sx); 1962 1963 return (0); 1964 } 1965 1966 void 1967 carp_detach(struct ifaddr *ifa, bool keep_cif) 1968 { 1969 struct ifnet *ifp = ifa->ifa_ifp; 1970 struct carp_if *cif = ifp->if_carp; 1971 struct carp_softc *sc = ifa->ifa_carp; 1972 int i, index; 1973 1974 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1975 1976 sx_xlock(&carp_sx); 1977 1978 CARP_LOCK(sc); 1979 /* Shift array. */ 1980 index = sc->sc_naddrs + sc->sc_naddrs6; 1981 for (i = 0; i < index; i++) 1982 if (sc->sc_ifas[i] == ifa) 1983 break; 1984 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1985 for (; i < index - 1; i++) 1986 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 1987 sc->sc_ifas[index - 1] = NULL; 1988 1989 switch (ifa->ifa_addr->sa_family) { 1990 #ifdef INET 1991 case AF_INET: 1992 cif->cif_naddrs--; 1993 sc->sc_naddrs--; 1994 break; 1995 #endif 1996 #ifdef INET6 1997 case AF_INET6: 1998 cif->cif_naddrs6--; 1999 sc->sc_naddrs6--; 2000 break; 2001 #endif 2002 } 2003 2004 carp_ifa_delroute(ifa); 2005 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 2006 2007 ifa->ifa_carp = NULL; 2008 ifa_free(ifa); 2009 2010 carp_hmac_prepare(sc); 2011 carp_sc_state(sc); 2012 2013 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2014 carp_destroy(sc); 2015 else 2016 CARP_UNLOCK(sc); 2017 2018 if (!keep_cif) 2019 CIF_FREE(cif); 2020 2021 sx_xunlock(&carp_sx); 2022 } 2023 2024 static void 2025 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2026 { 2027 2028 CARP_LOCK_ASSERT(sc); 2029 2030 if (sc->sc_state != state) { 2031 const char *carp_states[] = { CARP_STATES }; 2032 char subsys[IFNAMSIZ+5]; 2033 2034 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2035 sc->sc_carpdev->if_xname); 2036 2037 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2038 carp_states[sc->sc_state], carp_states[state], reason); 2039 2040 sc->sc_state = state; 2041 2042 devctl_notify("CARP", subsys, carp_states[state], NULL); 2043 } 2044 } 2045 2046 static void 2047 carp_linkstate(struct ifnet *ifp) 2048 { 2049 struct carp_softc *sc; 2050 2051 CIF_LOCK(ifp->if_carp); 2052 IFNET_FOREACH_CARP(ifp, sc) { 2053 CARP_LOCK(sc); 2054 carp_sc_state(sc); 2055 CARP_UNLOCK(sc); 2056 } 2057 CIF_UNLOCK(ifp->if_carp); 2058 } 2059 2060 static void 2061 carp_sc_state(struct carp_softc *sc) 2062 { 2063 2064 CARP_LOCK_ASSERT(sc); 2065 2066 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2067 !(sc->sc_carpdev->if_flags & IFF_UP)) { 2068 callout_stop(&sc->sc_ad_tmo); 2069 #ifdef INET 2070 callout_stop(&sc->sc_md_tmo); 2071 #endif 2072 #ifdef INET6 2073 callout_stop(&sc->sc_md6_tmo); 2074 #endif 2075 carp_set_state(sc, INIT, "hardware interface down"); 2076 carp_setrun(sc, 0); 2077 if (!sc->sc_suppress) 2078 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2079 sc->sc_suppress = 1; 2080 } else { 2081 carp_set_state(sc, INIT, "hardware interface up"); 2082 carp_setrun(sc, 0); 2083 if (sc->sc_suppress) 2084 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2085 sc->sc_suppress = 0; 2086 } 2087 } 2088 2089 static void 2090 carp_demote_adj(int adj, char *reason) 2091 { 2092 atomic_add_int(&V_carp_demotion, adj); 2093 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2094 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2095 } 2096 2097 static int 2098 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2099 { 2100 int new, error; 2101 2102 new = V_carp_demotion; 2103 error = sysctl_handle_int(oidp, &new, 0, req); 2104 if (error || !req->newptr) 2105 return (error); 2106 2107 carp_demote_adj(new, "sysctl"); 2108 2109 return (0); 2110 } 2111 2112 #ifdef INET 2113 extern struct domain inetdomain; 2114 static struct protosw in_carp_protosw = { 2115 .pr_type = SOCK_RAW, 2116 .pr_domain = &inetdomain, 2117 .pr_protocol = IPPROTO_CARP, 2118 .pr_flags = PR_ATOMIC|PR_ADDR, 2119 .pr_input = carp_input, 2120 .pr_output = rip_output, 2121 .pr_ctloutput = rip_ctloutput, 2122 .pr_usrreqs = &rip_usrreqs 2123 }; 2124 #endif 2125 2126 #ifdef INET6 2127 extern struct domain inet6domain; 2128 static struct protosw in6_carp_protosw = { 2129 .pr_type = SOCK_RAW, 2130 .pr_domain = &inet6domain, 2131 .pr_protocol = IPPROTO_CARP, 2132 .pr_flags = PR_ATOMIC|PR_ADDR, 2133 .pr_input = carp6_input, 2134 .pr_output = rip6_output, 2135 .pr_ctloutput = rip6_ctloutput, 2136 .pr_usrreqs = &rip6_usrreqs 2137 }; 2138 #endif 2139 2140 static void 2141 carp_mod_cleanup(void) 2142 { 2143 2144 #ifdef INET 2145 if (proto_reg[CARP_INET] == 0) { 2146 (void)ipproto_unregister(IPPROTO_CARP); 2147 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2148 proto_reg[CARP_INET] = -1; 2149 } 2150 carp_iamatch_p = NULL; 2151 #endif 2152 #ifdef INET6 2153 if (proto_reg[CARP_INET6] == 0) { 2154 (void)ip6proto_unregister(IPPROTO_CARP); 2155 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2156 proto_reg[CARP_INET6] = -1; 2157 } 2158 carp_iamatch6_p = NULL; 2159 carp_macmatch6_p = NULL; 2160 #endif 2161 carp_ioctl_p = NULL; 2162 carp_attach_p = NULL; 2163 carp_detach_p = NULL; 2164 carp_get_vhid_p = NULL; 2165 carp_linkstate_p = NULL; 2166 carp_forus_p = NULL; 2167 carp_output_p = NULL; 2168 carp_demote_adj_p = NULL; 2169 carp_master_p = NULL; 2170 mtx_unlock(&carp_mtx); 2171 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2172 mtx_destroy(&carp_mtx); 2173 sx_destroy(&carp_sx); 2174 } 2175 2176 static int 2177 carp_mod_load(void) 2178 { 2179 int err; 2180 2181 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2182 sx_init(&carp_sx, "carp_sx"); 2183 LIST_INIT(&carp_list); 2184 carp_get_vhid_p = carp_get_vhid; 2185 carp_forus_p = carp_forus; 2186 carp_output_p = carp_output; 2187 carp_linkstate_p = carp_linkstate; 2188 carp_ioctl_p = carp_ioctl; 2189 carp_attach_p = carp_attach; 2190 carp_detach_p = carp_detach; 2191 carp_demote_adj_p = carp_demote_adj; 2192 carp_master_p = carp_master; 2193 #ifdef INET6 2194 carp_iamatch6_p = carp_iamatch6; 2195 carp_macmatch6_p = carp_macmatch6; 2196 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2197 (struct protosw *)&in6_carp_protosw); 2198 if (proto_reg[CARP_INET6]) { 2199 printf("carp: error %d attaching to PF_INET6\n", 2200 proto_reg[CARP_INET6]); 2201 carp_mod_cleanup(); 2202 return (proto_reg[CARP_INET6]); 2203 } 2204 err = ip6proto_register(IPPROTO_CARP); 2205 if (err) { 2206 printf("carp: error %d registering with INET6\n", err); 2207 carp_mod_cleanup(); 2208 return (err); 2209 } 2210 #endif 2211 #ifdef INET 2212 carp_iamatch_p = carp_iamatch; 2213 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2214 if (proto_reg[CARP_INET]) { 2215 printf("carp: error %d attaching to PF_INET\n", 2216 proto_reg[CARP_INET]); 2217 carp_mod_cleanup(); 2218 return (proto_reg[CARP_INET]); 2219 } 2220 err = ipproto_register(IPPROTO_CARP); 2221 if (err) { 2222 printf("carp: error %d registering with INET\n", err); 2223 carp_mod_cleanup(); 2224 return (err); 2225 } 2226 #endif 2227 return (0); 2228 } 2229 2230 static int 2231 carp_modevent(module_t mod, int type, void *data) 2232 { 2233 switch (type) { 2234 case MOD_LOAD: 2235 return carp_mod_load(); 2236 /* NOTREACHED */ 2237 case MOD_UNLOAD: 2238 mtx_lock(&carp_mtx); 2239 if (LIST_EMPTY(&carp_list)) 2240 carp_mod_cleanup(); 2241 else { 2242 mtx_unlock(&carp_mtx); 2243 return (EBUSY); 2244 } 2245 break; 2246 2247 default: 2248 return (EINVAL); 2249 } 2250 2251 return (0); 2252 } 2253 2254 static moduledata_t carp_mod = { 2255 "carp", 2256 carp_modevent, 2257 0 2258 }; 2259 2260 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2261