1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002 Michael Shalayeff. 5 * Copyright (c) 2003 Ryan McBride. 6 * Copyright (c) 2011 Gleb Smirnoff <glebius@FreeBSD.org> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT, 22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 24 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 28 * THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_bpf.h" 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bus.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/limits.h> 44 #include <sys/malloc.h> 45 #include <sys/mbuf.h> 46 #include <sys/module.h> 47 #include <sys/priv.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/sockio.h> 52 #include <sys/sysctl.h> 53 #include <sys/syslog.h> 54 #include <sys/taskqueue.h> 55 #include <sys/counter.h> 56 57 #include <net/ethernet.h> 58 #include <net/fddi.h> 59 #include <net/if.h> 60 #include <net/if_var.h> 61 #include <net/if_dl.h> 62 #include <net/if_llatbl.h> 63 #include <net/if_types.h> 64 #include <net/route.h> 65 #include <net/vnet.h> 66 67 #if defined(INET) || defined(INET6) 68 #include <netinet/in.h> 69 #include <netinet/in_var.h> 70 #include <netinet/ip_carp.h> 71 #include <netinet/ip.h> 72 #include <machine/in_cksum.h> 73 #endif 74 #ifdef INET 75 #include <netinet/ip_var.h> 76 #include <netinet/if_ether.h> 77 #endif 78 79 #ifdef INET6 80 #include <netinet/icmp6.h> 81 #include <netinet/ip6.h> 82 #include <netinet6/in6_var.h> 83 #include <netinet6/ip6_var.h> 84 #include <netinet6/scope6_var.h> 85 #include <netinet6/nd6.h> 86 #endif 87 88 #include <crypto/sha1.h> 89 90 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses"); 91 92 struct carp_softc { 93 struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */ 94 struct ifaddr **sc_ifas; /* Our ifaddrs. */ 95 struct sockaddr_dl sc_addr; /* Our link level address. */ 96 struct callout sc_ad_tmo; /* Advertising timeout. */ 97 #ifdef INET 98 struct callout sc_md_tmo; /* Master down timeout. */ 99 #endif 100 #ifdef INET6 101 struct callout sc_md6_tmo; /* XXX: Master down timeout. */ 102 #endif 103 struct mtx sc_mtx; 104 105 int sc_vhid; 106 int sc_advskew; 107 int sc_advbase; 108 109 int sc_naddrs; 110 int sc_naddrs6; 111 int sc_ifasiz; 112 enum { INIT = 0, BACKUP, MASTER } sc_state; 113 int sc_suppress; 114 int sc_sendad_errors; 115 #define CARP_SENDAD_MAX_ERRORS 3 116 int sc_sendad_success; 117 #define CARP_SENDAD_MIN_SUCCESS 3 118 119 int sc_init_counter; 120 uint64_t sc_counter; 121 122 /* authentication */ 123 #define CARP_HMAC_PAD 64 124 unsigned char sc_key[CARP_KEY_LEN]; 125 unsigned char sc_pad[CARP_HMAC_PAD]; 126 SHA1_CTX sc_sha1; 127 128 TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */ 129 LIST_ENTRY(carp_softc) sc_next; /* On the global list. */ 130 }; 131 132 struct carp_if { 133 #ifdef INET 134 int cif_naddrs; 135 #endif 136 #ifdef INET6 137 int cif_naddrs6; 138 #endif 139 TAILQ_HEAD(, carp_softc) cif_vrs; 140 #ifdef INET 141 struct ip_moptions cif_imo; 142 #endif 143 #ifdef INET6 144 struct ip6_moptions cif_im6o; 145 #endif 146 struct ifnet *cif_ifp; 147 struct mtx cif_mtx; 148 uint32_t cif_flags; 149 #define CIF_PROMISC 0x00000001 150 }; 151 152 #define CARP_INET 0 153 #define CARP_INET6 1 154 static int proto_reg[] = {-1, -1}; 155 156 /* 157 * Brief design of carp(4). 158 * 159 * Any carp-capable ifnet may have a list of carp softcs hanging off 160 * its ifp->if_carp pointer. Each softc represents one unique virtual 161 * host id, or vhid. The softc has a back pointer to the ifnet. All 162 * softcs are joined in a global list, which has quite limited use. 163 * 164 * Any interface address that takes part in CARP negotiation has a 165 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either 166 * AF_INET or AF_INET6 address. 167 * 168 * Although, one can get the softc's backpointer to ifnet and traverse 169 * through its ifp->if_addrhead queue to find all interface addresses 170 * involved in CARP, we keep a growable array of ifaddr pointers. This 171 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that 172 * do calls into the network stack, thus avoiding LORs. 173 * 174 * Locking: 175 * 176 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), 177 * callout-driven events and ioctl()s. 178 * 179 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. 180 * To traverse the global list we use the mutex carp_mtx. 181 * 182 * Known issues with locking: 183 * 184 * - Sending ad, we put the pointer to the softc in an mtag, and no reference 185 * counting is done on the softc. 186 * - On module unload we may race (?) with packet processing thread 187 * dereferencing our function pointers. 188 */ 189 190 /* Accept incoming CARP packets. */ 191 static VNET_DEFINE(int, carp_allow) = 1; 192 #define V_carp_allow VNET(carp_allow) 193 194 /* Preempt slower nodes. */ 195 static VNET_DEFINE(int, carp_preempt) = 0; 196 #define V_carp_preempt VNET(carp_preempt) 197 198 /* Log level. */ 199 static VNET_DEFINE(int, carp_log) = 1; 200 #define V_carp_log VNET(carp_log) 201 202 /* Global advskew demotion. */ 203 static VNET_DEFINE(int, carp_demotion) = 0; 204 #define V_carp_demotion VNET(carp_demotion) 205 206 /* Send error demotion factor. */ 207 static VNET_DEFINE(int, carp_senderr_adj) = CARP_MAXSKEW; 208 #define V_carp_senderr_adj VNET(carp_senderr_adj) 209 210 /* Iface down demotion factor. */ 211 static VNET_DEFINE(int, carp_ifdown_adj) = CARP_MAXSKEW; 212 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 213 214 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 215 216 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW, 0, "CARP"); 217 SYSCTL_INT(_net_inet_carp, OID_AUTO, allow, CTLFLAG_VNET | CTLFLAG_RW, 218 &VNET_NAME(carp_allow), 0, "Accept incoming CARP packets"); 219 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 220 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 221 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 222 &VNET_NAME(carp_log), 0, "CARP log level"); 223 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 224 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 225 0, 0, carp_demote_adj_sysctl, "I", 226 "Adjust demotion factor (skew of advskew)"); 227 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 228 CTLFLAG_VNET | CTLFLAG_RW, 229 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 230 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 231 CTLFLAG_VNET | CTLFLAG_RW, 232 &VNET_NAME(carp_ifdown_adj), 0, 233 "Interface down demotion factor adjustment"); 234 235 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 236 VNET_PCPUSTAT_SYSINIT(carpstats); 237 VNET_PCPUSTAT_SYSUNINIT(carpstats); 238 239 #define CARPSTATS_ADD(name, val) \ 240 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 241 sizeof(uint64_t)], (val)) 242 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 243 244 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 245 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 246 247 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 248 NULL, MTX_DEF) 249 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 250 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 251 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 252 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 253 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 254 NULL, MTX_DEF) 255 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 256 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 257 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 258 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 259 #define CIF_FREE(cif) do { \ 260 CIF_LOCK(cif); \ 261 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 262 carp_free_if(cif); \ 263 else \ 264 CIF_UNLOCK(cif); \ 265 } while (0) 266 267 #define CARP_LOG(...) do { \ 268 if (V_carp_log > 0) \ 269 log(LOG_INFO, "carp: " __VA_ARGS__); \ 270 } while (0) 271 272 #define CARP_DEBUG(...) do { \ 273 if (V_carp_log > 1) \ 274 log(LOG_DEBUG, __VA_ARGS__); \ 275 } while (0) 276 277 #define IFNET_FOREACH_IFA(ifp, ifa) \ 278 IF_ADDR_LOCK_ASSERT(ifp); \ 279 TAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 280 if ((ifa)->ifa_carp != NULL) 281 282 #define CARP_FOREACH_IFA(sc, ifa) \ 283 CARP_LOCK_ASSERT(sc); \ 284 for (int _i = 0; \ 285 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 286 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 287 ++_i) 288 289 #define IFNET_FOREACH_CARP(ifp, sc) \ 290 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 291 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 292 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 293 294 #define DEMOTE_ADVSKEW(sc) \ 295 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 296 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) 297 298 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 299 static struct carp_softc 300 *carp_alloc(struct ifnet *); 301 static void carp_destroy(struct carp_softc *); 302 static struct carp_if 303 *carp_alloc_if(struct ifnet *); 304 static void carp_free_if(struct carp_if *); 305 static void carp_set_state(struct carp_softc *, int, const char* reason); 306 static void carp_sc_state(struct carp_softc *); 307 static void carp_setrun(struct carp_softc *, sa_family_t); 308 static void carp_master_down(void *); 309 static void carp_master_down_locked(struct carp_softc *, 310 const char* reason); 311 static void carp_send_ad(void *); 312 static void carp_send_ad_locked(struct carp_softc *); 313 static void carp_addroute(struct carp_softc *); 314 static void carp_ifa_addroute(struct ifaddr *); 315 static void carp_delroute(struct carp_softc *); 316 static void carp_ifa_delroute(struct ifaddr *); 317 static void carp_send_ad_all(void *, int); 318 static void carp_demote_adj(int, char *); 319 320 static LIST_HEAD(, carp_softc) carp_list; 321 static struct mtx carp_mtx; 322 static struct sx carp_sx; 323 static struct task carp_sendall_task = 324 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 325 326 static void 327 carp_hmac_prepare(struct carp_softc *sc) 328 { 329 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 330 uint8_t vhid = sc->sc_vhid & 0xff; 331 struct ifaddr *ifa; 332 int i, found; 333 #ifdef INET 334 struct in_addr last, cur, in; 335 #endif 336 #ifdef INET6 337 struct in6_addr last6, cur6, in6; 338 #endif 339 340 CARP_LOCK_ASSERT(sc); 341 342 /* Compute ipad from key. */ 343 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 344 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 345 for (i = 0; i < sizeof(sc->sc_pad); i++) 346 sc->sc_pad[i] ^= 0x36; 347 348 /* Precompute first part of inner hash. */ 349 SHA1Init(&sc->sc_sha1); 350 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 351 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 352 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 353 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 354 #ifdef INET 355 cur.s_addr = 0; 356 do { 357 found = 0; 358 last = cur; 359 cur.s_addr = 0xffffffff; 360 CARP_FOREACH_IFA(sc, ifa) { 361 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 362 if (ifa->ifa_addr->sa_family == AF_INET && 363 ntohl(in.s_addr) > ntohl(last.s_addr) && 364 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 365 cur.s_addr = in.s_addr; 366 found++; 367 } 368 } 369 if (found) 370 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 371 } while (found); 372 #endif /* INET */ 373 #ifdef INET6 374 memset(&cur6, 0, sizeof(cur6)); 375 do { 376 found = 0; 377 last6 = cur6; 378 memset(&cur6, 0xff, sizeof(cur6)); 379 CARP_FOREACH_IFA(sc, ifa) { 380 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 381 if (IN6_IS_SCOPE_EMBED(&in6)) 382 in6.s6_addr16[1] = 0; 383 if (ifa->ifa_addr->sa_family == AF_INET6 && 384 memcmp(&in6, &last6, sizeof(in6)) > 0 && 385 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 386 cur6 = in6; 387 found++; 388 } 389 } 390 if (found) 391 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 392 } while (found); 393 #endif /* INET6 */ 394 395 /* convert ipad to opad */ 396 for (i = 0; i < sizeof(sc->sc_pad); i++) 397 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 398 } 399 400 static void 401 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 402 unsigned char md[20]) 403 { 404 SHA1_CTX sha1ctx; 405 406 CARP_LOCK_ASSERT(sc); 407 408 /* fetch first half of inner hash */ 409 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 410 411 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 412 SHA1Final(md, &sha1ctx); 413 414 /* outer hash */ 415 SHA1Init(&sha1ctx); 416 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 417 SHA1Update(&sha1ctx, md, 20); 418 SHA1Final(md, &sha1ctx); 419 } 420 421 static int 422 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 423 unsigned char md[20]) 424 { 425 unsigned char md2[20]; 426 427 CARP_LOCK_ASSERT(sc); 428 429 carp_hmac_generate(sc, counter, md2); 430 431 return (bcmp(md, md2, sizeof(md2))); 432 } 433 434 /* 435 * process input packet. 436 * we have rearranged checks order compared to the rfc, 437 * but it seems more efficient this way or not possible otherwise. 438 */ 439 #ifdef INET 440 int 441 carp_input(struct mbuf **mp, int *offp, int proto) 442 { 443 struct mbuf *m = *mp; 444 struct ip *ip = mtod(m, struct ip *); 445 struct carp_header *ch; 446 int iplen, len; 447 448 iplen = *offp; 449 *mp = NULL; 450 451 CARPSTATS_INC(carps_ipackets); 452 453 if (!V_carp_allow) { 454 m_freem(m); 455 return (IPPROTO_DONE); 456 } 457 458 /* verify that the IP TTL is 255. */ 459 if (ip->ip_ttl != CARP_DFLTTL) { 460 CARPSTATS_INC(carps_badttl); 461 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 462 ip->ip_ttl, 463 m->m_pkthdr.rcvif->if_xname); 464 m_freem(m); 465 return (IPPROTO_DONE); 466 } 467 468 iplen = ip->ip_hl << 2; 469 470 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 471 CARPSTATS_INC(carps_badlen); 472 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 473 "on %s\n", __func__, m->m_len - sizeof(struct ip), 474 m->m_pkthdr.rcvif->if_xname); 475 m_freem(m); 476 return (IPPROTO_DONE); 477 } 478 479 if (iplen + sizeof(*ch) < m->m_len) { 480 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 481 CARPSTATS_INC(carps_hdrops); 482 CARP_DEBUG("%s: pullup failed\n", __func__); 483 return (IPPROTO_DONE); 484 } 485 ip = mtod(m, struct ip *); 486 } 487 ch = (struct carp_header *)((char *)ip + iplen); 488 489 /* 490 * verify that the received packet length is 491 * equal to the CARP header 492 */ 493 len = iplen + sizeof(*ch); 494 if (len > m->m_pkthdr.len) { 495 CARPSTATS_INC(carps_badlen); 496 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 497 m->m_pkthdr.len, 498 m->m_pkthdr.rcvif->if_xname); 499 m_freem(m); 500 return (IPPROTO_DONE); 501 } 502 503 if ((m = m_pullup(m, len)) == NULL) { 504 CARPSTATS_INC(carps_hdrops); 505 return (IPPROTO_DONE); 506 } 507 ip = mtod(m, struct ip *); 508 ch = (struct carp_header *)((char *)ip + iplen); 509 510 /* verify the CARP checksum */ 511 m->m_data += iplen; 512 if (in_cksum(m, len - iplen)) { 513 CARPSTATS_INC(carps_badsum); 514 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 515 m->m_pkthdr.rcvif->if_xname); 516 m_freem(m); 517 return (IPPROTO_DONE); 518 } 519 m->m_data -= iplen; 520 521 carp_input_c(m, ch, AF_INET); 522 return (IPPROTO_DONE); 523 } 524 #endif 525 526 #ifdef INET6 527 int 528 carp6_input(struct mbuf **mp, int *offp, int proto) 529 { 530 struct mbuf *m = *mp; 531 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 532 struct carp_header *ch; 533 u_int len; 534 535 CARPSTATS_INC(carps_ipackets6); 536 537 if (!V_carp_allow) { 538 m_freem(m); 539 return (IPPROTO_DONE); 540 } 541 542 /* check if received on a valid carp interface */ 543 if (m->m_pkthdr.rcvif->if_carp == NULL) { 544 CARPSTATS_INC(carps_badif); 545 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 546 __func__, m->m_pkthdr.rcvif->if_xname); 547 m_freem(m); 548 return (IPPROTO_DONE); 549 } 550 551 /* verify that the IP TTL is 255 */ 552 if (ip6->ip6_hlim != CARP_DFLTTL) { 553 CARPSTATS_INC(carps_badttl); 554 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 555 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 556 m_freem(m); 557 return (IPPROTO_DONE); 558 } 559 560 /* verify that we have a complete carp packet */ 561 len = m->m_len; 562 IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch)); 563 if (ch == NULL) { 564 CARPSTATS_INC(carps_badlen); 565 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 566 return (IPPROTO_DONE); 567 } 568 569 570 /* verify the CARP checksum */ 571 m->m_data += *offp; 572 if (in_cksum(m, sizeof(*ch))) { 573 CARPSTATS_INC(carps_badsum); 574 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 575 m->m_pkthdr.rcvif->if_xname); 576 m_freem(m); 577 return (IPPROTO_DONE); 578 } 579 m->m_data -= *offp; 580 581 carp_input_c(m, ch, AF_INET6); 582 return (IPPROTO_DONE); 583 } 584 #endif /* INET6 */ 585 586 /* 587 * This routine should not be necessary at all, but some switches 588 * (VMWare ESX vswitches) can echo our own packets back at us, 589 * and we must ignore them or they will cause us to drop out of 590 * MASTER mode. 591 * 592 * We cannot catch all cases of network loops. Instead, what we 593 * do here is catch any packet that arrives with a carp header 594 * with a VHID of 0, that comes from an address that is our own. 595 * These packets are by definition "from us" (even if they are from 596 * a misconfigured host that is pretending to be us). 597 * 598 * The VHID test is outside this mini-function. 599 */ 600 static int 601 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 602 { 603 #ifdef INET 604 struct ip *ip4; 605 struct in_addr in4; 606 #endif 607 #ifdef INET6 608 struct ip6_hdr *ip6; 609 struct in6_addr in6; 610 #endif 611 612 switch (af) { 613 #ifdef INET 614 case AF_INET: 615 ip4 = mtod(m, struct ip *); 616 in4 = ifatoia(ifa)->ia_addr.sin_addr; 617 return (in4.s_addr == ip4->ip_src.s_addr); 618 #endif 619 #ifdef INET6 620 case AF_INET6: 621 ip6 = mtod(m, struct ip6_hdr *); 622 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 623 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 624 #endif 625 default: 626 break; 627 } 628 return (0); 629 } 630 631 static void 632 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 633 { 634 struct ifnet *ifp = m->m_pkthdr.rcvif; 635 struct ifaddr *ifa, *match; 636 struct carp_softc *sc; 637 uint64_t tmp_counter; 638 struct timeval sc_tv, ch_tv; 639 int error; 640 641 /* 642 * Verify that the VHID is valid on the receiving interface. 643 * 644 * There should be just one match. If there are none 645 * the VHID is not valid and we drop the packet. If 646 * there are multiple VHID matches, take just the first 647 * one, for compatibility with previous code. While we're 648 * scanning, check for obvious loops in the network topology 649 * (these should never happen, and as noted above, we may 650 * miss real loops; this is just a double-check). 651 */ 652 IF_ADDR_RLOCK(ifp); 653 error = 0; 654 match = NULL; 655 IFNET_FOREACH_IFA(ifp, ifa) { 656 if (match == NULL && ifa->ifa_carp != NULL && 657 ifa->ifa_addr->sa_family == af && 658 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 659 match = ifa; 660 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 661 error = ELOOP; 662 } 663 ifa = error ? NULL : match; 664 if (ifa != NULL) 665 ifa_ref(ifa); 666 IF_ADDR_RUNLOCK(ifp); 667 668 if (ifa == NULL) { 669 if (error == ELOOP) { 670 CARP_DEBUG("dropping looped packet on interface %s\n", 671 ifp->if_xname); 672 CARPSTATS_INC(carps_badif); /* ??? */ 673 } else { 674 CARPSTATS_INC(carps_badvhid); 675 } 676 m_freem(m); 677 return; 678 } 679 680 /* verify the CARP version. */ 681 if (ch->carp_version != CARP_VERSION) { 682 CARPSTATS_INC(carps_badver); 683 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 684 ch->carp_version); 685 ifa_free(ifa); 686 m_freem(m); 687 return; 688 } 689 690 sc = ifa->ifa_carp; 691 CARP_LOCK(sc); 692 ifa_free(ifa); 693 694 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 695 CARPSTATS_INC(carps_badauth); 696 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 697 sc->sc_vhid, ifp->if_xname); 698 goto out; 699 } 700 701 tmp_counter = ntohl(ch->carp_counter[0]); 702 tmp_counter = tmp_counter<<32; 703 tmp_counter += ntohl(ch->carp_counter[1]); 704 705 /* XXX Replay protection goes here */ 706 707 sc->sc_init_counter = 0; 708 sc->sc_counter = tmp_counter; 709 710 sc_tv.tv_sec = sc->sc_advbase; 711 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 712 ch_tv.tv_sec = ch->carp_advbase; 713 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 714 715 switch (sc->sc_state) { 716 case INIT: 717 break; 718 case MASTER: 719 /* 720 * If we receive an advertisement from a master who's going to 721 * be more frequent than us, go into BACKUP state. 722 */ 723 if (timevalcmp(&sc_tv, &ch_tv, >) || 724 timevalcmp(&sc_tv, &ch_tv, ==)) { 725 callout_stop(&sc->sc_ad_tmo); 726 carp_set_state(sc, BACKUP, 727 "more frequent advertisement received"); 728 carp_setrun(sc, 0); 729 carp_delroute(sc); 730 } 731 break; 732 case BACKUP: 733 /* 734 * If we're pre-empting masters who advertise slower than us, 735 * and this one claims to be slower, treat him as down. 736 */ 737 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 738 carp_master_down_locked(sc, 739 "preempting a slower master"); 740 break; 741 } 742 743 /* 744 * If the master is going to advertise at such a low frequency 745 * that he's guaranteed to time out, we'd might as well just 746 * treat him as timed out now. 747 */ 748 sc_tv.tv_sec = sc->sc_advbase * 3; 749 if (timevalcmp(&sc_tv, &ch_tv, <)) { 750 carp_master_down_locked(sc, "master will time out"); 751 break; 752 } 753 754 /* 755 * Otherwise, we reset the counter and wait for the next 756 * advertisement. 757 */ 758 carp_setrun(sc, af); 759 break; 760 } 761 762 out: 763 CARP_UNLOCK(sc); 764 m_freem(m); 765 } 766 767 static int 768 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 769 { 770 struct m_tag *mtag; 771 772 if (sc->sc_init_counter) { 773 /* this could also be seconds since unix epoch */ 774 sc->sc_counter = arc4random(); 775 sc->sc_counter = sc->sc_counter << 32; 776 sc->sc_counter += arc4random(); 777 } else 778 sc->sc_counter++; 779 780 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 781 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 782 783 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 784 785 /* Tag packet for carp_output */ 786 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 787 M_NOWAIT)) == NULL) { 788 m_freem(m); 789 CARPSTATS_INC(carps_onomem); 790 return (ENOMEM); 791 } 792 bcopy(&sc, mtag + 1, sizeof(sc)); 793 m_tag_prepend(m, mtag); 794 795 return (0); 796 } 797 798 /* 799 * To avoid LORs and possible recursions this function shouldn't 800 * be called directly, but scheduled via taskqueue. 801 */ 802 static void 803 carp_send_ad_all(void *ctx __unused, int pending __unused) 804 { 805 struct carp_softc *sc; 806 807 mtx_lock(&carp_mtx); 808 LIST_FOREACH(sc, &carp_list, sc_next) 809 if (sc->sc_state == MASTER) { 810 CARP_LOCK(sc); 811 CURVNET_SET(sc->sc_carpdev->if_vnet); 812 carp_send_ad_locked(sc); 813 CURVNET_RESTORE(); 814 CARP_UNLOCK(sc); 815 } 816 mtx_unlock(&carp_mtx); 817 } 818 819 /* Send a periodic advertisement, executed in callout context. */ 820 static void 821 carp_send_ad(void *v) 822 { 823 struct carp_softc *sc = v; 824 825 CARP_LOCK_ASSERT(sc); 826 CURVNET_SET(sc->sc_carpdev->if_vnet); 827 carp_send_ad_locked(sc); 828 CURVNET_RESTORE(); 829 CARP_UNLOCK(sc); 830 } 831 832 static void 833 carp_send_ad_error(struct carp_softc *sc, int error) 834 { 835 836 if (error) { 837 if (sc->sc_sendad_errors < INT_MAX) 838 sc->sc_sendad_errors++; 839 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 840 static const char fmt[] = "send error %d on %s"; 841 char msg[sizeof(fmt) + IFNAMSIZ]; 842 843 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 844 carp_demote_adj(V_carp_senderr_adj, msg); 845 } 846 sc->sc_sendad_success = 0; 847 } else { 848 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && 849 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 850 static const char fmt[] = "send ok on %s"; 851 char msg[sizeof(fmt) + IFNAMSIZ]; 852 853 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 854 carp_demote_adj(-V_carp_senderr_adj, msg); 855 sc->sc_sendad_errors = 0; 856 } else 857 sc->sc_sendad_errors = 0; 858 } 859 } 860 861 /* 862 * Pick the best ifaddr on the given ifp for sending CARP 863 * advertisements. 864 * 865 * "Best" here is defined by ifa_preferred(). This function is much 866 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 867 * 868 * (This could be simplified to return the actual address, except that 869 * it has a different format in AF_INET and AF_INET6.) 870 */ 871 static struct ifaddr * 872 carp_best_ifa(int af, struct ifnet *ifp) 873 { 874 struct ifaddr *ifa, *best; 875 876 if (af >= AF_MAX) 877 return (NULL); 878 best = NULL; 879 IF_ADDR_RLOCK(ifp); 880 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 881 if (ifa->ifa_addr->sa_family == af && 882 (best == NULL || ifa_preferred(best, ifa))) 883 best = ifa; 884 } 885 IF_ADDR_RUNLOCK(ifp); 886 if (best != NULL) 887 ifa_ref(best); 888 return (best); 889 } 890 891 static void 892 carp_send_ad_locked(struct carp_softc *sc) 893 { 894 struct carp_header ch; 895 struct timeval tv; 896 struct ifaddr *ifa; 897 struct carp_header *ch_ptr; 898 struct mbuf *m; 899 int len, advskew; 900 901 CARP_LOCK_ASSERT(sc); 902 903 advskew = DEMOTE_ADVSKEW(sc); 904 tv.tv_sec = sc->sc_advbase; 905 tv.tv_usec = advskew * 1000000 / 256; 906 907 ch.carp_version = CARP_VERSION; 908 ch.carp_type = CARP_ADVERTISEMENT; 909 ch.carp_vhid = sc->sc_vhid; 910 ch.carp_advbase = sc->sc_advbase; 911 ch.carp_advskew = advskew; 912 ch.carp_authlen = 7; /* XXX DEFINE */ 913 ch.carp_pad1 = 0; /* must be zero */ 914 ch.carp_cksum = 0; 915 916 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 917 918 #ifdef INET 919 if (sc->sc_naddrs) { 920 struct ip *ip; 921 922 m = m_gethdr(M_NOWAIT, MT_DATA); 923 if (m == NULL) { 924 CARPSTATS_INC(carps_onomem); 925 goto resched; 926 } 927 len = sizeof(*ip) + sizeof(ch); 928 m->m_pkthdr.len = len; 929 m->m_pkthdr.rcvif = NULL; 930 m->m_len = len; 931 M_ALIGN(m, m->m_len); 932 m->m_flags |= M_MCAST; 933 ip = mtod(m, struct ip *); 934 ip->ip_v = IPVERSION; 935 ip->ip_hl = sizeof(*ip) >> 2; 936 ip->ip_tos = IPTOS_LOWDELAY; 937 ip->ip_len = htons(len); 938 ip->ip_off = htons(IP_DF); 939 ip->ip_ttl = CARP_DFLTTL; 940 ip->ip_p = IPPROTO_CARP; 941 ip->ip_sum = 0; 942 ip_fillid(ip); 943 944 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 945 if (ifa != NULL) { 946 ip->ip_src.s_addr = 947 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 948 ifa_free(ifa); 949 } else 950 ip->ip_src.s_addr = 0; 951 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 952 953 ch_ptr = (struct carp_header *)(&ip[1]); 954 bcopy(&ch, ch_ptr, sizeof(ch)); 955 if (carp_prepare_ad(m, sc, ch_ptr)) 956 goto resched; 957 958 m->m_data += sizeof(*ip); 959 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 960 m->m_data -= sizeof(*ip); 961 962 CARPSTATS_INC(carps_opackets); 963 964 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 965 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 966 } 967 #endif /* INET */ 968 #ifdef INET6 969 if (sc->sc_naddrs6) { 970 struct ip6_hdr *ip6; 971 972 m = m_gethdr(M_NOWAIT, MT_DATA); 973 if (m == NULL) { 974 CARPSTATS_INC(carps_onomem); 975 goto resched; 976 } 977 len = sizeof(*ip6) + sizeof(ch); 978 m->m_pkthdr.len = len; 979 m->m_pkthdr.rcvif = NULL; 980 m->m_len = len; 981 M_ALIGN(m, m->m_len); 982 m->m_flags |= M_MCAST; 983 ip6 = mtod(m, struct ip6_hdr *); 984 bzero(ip6, sizeof(*ip6)); 985 ip6->ip6_vfc |= IPV6_VERSION; 986 ip6->ip6_hlim = CARP_DFLTTL; 987 ip6->ip6_nxt = IPPROTO_CARP; 988 989 /* set the source address */ 990 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 991 if (ifa != NULL) { 992 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 993 sizeof(struct in6_addr)); 994 ifa_free(ifa); 995 } else 996 /* This should never happen with IPv6. */ 997 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 998 999 /* Set the multicast destination. */ 1000 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1001 ip6->ip6_dst.s6_addr8[15] = 0x12; 1002 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1003 m_freem(m); 1004 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1005 goto resched; 1006 } 1007 1008 ch_ptr = (struct carp_header *)(&ip6[1]); 1009 bcopy(&ch, ch_ptr, sizeof(ch)); 1010 if (carp_prepare_ad(m, sc, ch_ptr)) 1011 goto resched; 1012 1013 m->m_data += sizeof(*ip6); 1014 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1015 m->m_data -= sizeof(*ip6); 1016 1017 CARPSTATS_INC(carps_opackets6); 1018 1019 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1020 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1021 } 1022 #endif /* INET6 */ 1023 1024 resched: 1025 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1026 } 1027 1028 static void 1029 carp_addroute(struct carp_softc *sc) 1030 { 1031 struct ifaddr *ifa; 1032 1033 CARP_FOREACH_IFA(sc, ifa) 1034 carp_ifa_addroute(ifa); 1035 } 1036 1037 static void 1038 carp_ifa_addroute(struct ifaddr *ifa) 1039 { 1040 1041 switch (ifa->ifa_addr->sa_family) { 1042 #ifdef INET 1043 case AF_INET: 1044 in_addprefix(ifatoia(ifa), RTF_UP); 1045 ifa_add_loopback_route(ifa, 1046 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1047 break; 1048 #endif 1049 #ifdef INET6 1050 case AF_INET6: 1051 ifa_add_loopback_route(ifa, 1052 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1053 nd6_add_ifa_lle(ifatoia6(ifa)); 1054 break; 1055 #endif 1056 } 1057 } 1058 1059 static void 1060 carp_delroute(struct carp_softc *sc) 1061 { 1062 struct ifaddr *ifa; 1063 1064 CARP_FOREACH_IFA(sc, ifa) 1065 carp_ifa_delroute(ifa); 1066 } 1067 1068 static void 1069 carp_ifa_delroute(struct ifaddr *ifa) 1070 { 1071 1072 switch (ifa->ifa_addr->sa_family) { 1073 #ifdef INET 1074 case AF_INET: 1075 ifa_del_loopback_route(ifa, 1076 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1077 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1078 break; 1079 #endif 1080 #ifdef INET6 1081 case AF_INET6: 1082 ifa_del_loopback_route(ifa, 1083 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1084 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1085 break; 1086 #endif 1087 } 1088 } 1089 1090 int 1091 carp_master(struct ifaddr *ifa) 1092 { 1093 struct carp_softc *sc = ifa->ifa_carp; 1094 1095 return (sc->sc_state == MASTER); 1096 } 1097 1098 #ifdef INET 1099 /* 1100 * Broadcast a gratuitous ARP request containing 1101 * the virtual router MAC address for each IP address 1102 * associated with the virtual router. 1103 */ 1104 static void 1105 carp_send_arp(struct carp_softc *sc) 1106 { 1107 struct ifaddr *ifa; 1108 struct in_addr addr; 1109 1110 CARP_FOREACH_IFA(sc, ifa) { 1111 if (ifa->ifa_addr->sa_family != AF_INET) 1112 continue; 1113 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1114 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1115 } 1116 } 1117 1118 int 1119 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1120 { 1121 struct carp_softc *sc = ifa->ifa_carp; 1122 1123 if (sc->sc_state == MASTER) { 1124 *enaddr = LLADDR(&sc->sc_addr); 1125 return (1); 1126 } 1127 1128 return (0); 1129 } 1130 #endif 1131 1132 #ifdef INET6 1133 static void 1134 carp_send_na(struct carp_softc *sc) 1135 { 1136 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1137 struct ifaddr *ifa; 1138 struct in6_addr *in6; 1139 1140 CARP_FOREACH_IFA(sc, ifa) { 1141 if (ifa->ifa_addr->sa_family != AF_INET6) 1142 continue; 1143 1144 in6 = IFA_IN6(ifa); 1145 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1146 ND_NA_FLAG_OVERRIDE, 1, NULL); 1147 DELAY(1000); /* XXX */ 1148 } 1149 } 1150 1151 /* 1152 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1153 * matches and is not a carp address. Returns NULL otherwise. 1154 */ 1155 struct ifaddr * 1156 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1157 { 1158 struct ifaddr *ifa; 1159 1160 ifa = NULL; 1161 IF_ADDR_RLOCK(ifp); 1162 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1163 if (ifa->ifa_addr->sa_family != AF_INET6) 1164 continue; 1165 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1166 continue; 1167 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1168 ifa = NULL; 1169 else 1170 ifa_ref(ifa); 1171 break; 1172 } 1173 IF_ADDR_RUNLOCK(ifp); 1174 1175 return (ifa); 1176 } 1177 1178 caddr_t 1179 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1180 { 1181 struct ifaddr *ifa; 1182 1183 IF_ADDR_RLOCK(ifp); 1184 IFNET_FOREACH_IFA(ifp, ifa) 1185 if (ifa->ifa_addr->sa_family == AF_INET6 && 1186 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1187 struct carp_softc *sc = ifa->ifa_carp; 1188 struct m_tag *mtag; 1189 1190 IF_ADDR_RUNLOCK(ifp); 1191 1192 mtag = m_tag_get(PACKET_TAG_CARP, 1193 sizeof(struct carp_softc *), M_NOWAIT); 1194 if (mtag == NULL) 1195 /* Better a bit than nothing. */ 1196 return (LLADDR(&sc->sc_addr)); 1197 1198 bcopy(&sc, mtag + 1, sizeof(sc)); 1199 m_tag_prepend(m, mtag); 1200 1201 return (LLADDR(&sc->sc_addr)); 1202 } 1203 IF_ADDR_RUNLOCK(ifp); 1204 1205 return (NULL); 1206 } 1207 #endif /* INET6 */ 1208 1209 int 1210 carp_forus(struct ifnet *ifp, u_char *dhost) 1211 { 1212 struct carp_softc *sc; 1213 uint8_t *ena = dhost; 1214 1215 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1216 return (0); 1217 1218 CIF_LOCK(ifp->if_carp); 1219 IFNET_FOREACH_CARP(ifp, sc) { 1220 CARP_LOCK(sc); 1221 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1222 ETHER_ADDR_LEN)) { 1223 CARP_UNLOCK(sc); 1224 CIF_UNLOCK(ifp->if_carp); 1225 return (1); 1226 } 1227 CARP_UNLOCK(sc); 1228 } 1229 CIF_UNLOCK(ifp->if_carp); 1230 1231 return (0); 1232 } 1233 1234 /* Master down timeout event, executed in callout context. */ 1235 static void 1236 carp_master_down(void *v) 1237 { 1238 struct carp_softc *sc = v; 1239 1240 CARP_LOCK_ASSERT(sc); 1241 1242 CURVNET_SET(sc->sc_carpdev->if_vnet); 1243 if (sc->sc_state == BACKUP) { 1244 carp_master_down_locked(sc, "master timed out"); 1245 } 1246 CURVNET_RESTORE(); 1247 1248 CARP_UNLOCK(sc); 1249 } 1250 1251 static void 1252 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1253 { 1254 1255 CARP_LOCK_ASSERT(sc); 1256 1257 switch (sc->sc_state) { 1258 case BACKUP: 1259 carp_set_state(sc, MASTER, reason); 1260 carp_send_ad_locked(sc); 1261 #ifdef INET 1262 carp_send_arp(sc); 1263 #endif 1264 #ifdef INET6 1265 carp_send_na(sc); 1266 #endif 1267 carp_setrun(sc, 0); 1268 carp_addroute(sc); 1269 break; 1270 case INIT: 1271 case MASTER: 1272 #ifdef INVARIANTS 1273 panic("carp: VHID %u@%s: master_down event in %s state\n", 1274 sc->sc_vhid, 1275 sc->sc_carpdev->if_xname, 1276 sc->sc_state ? "MASTER" : "INIT"); 1277 #endif 1278 break; 1279 } 1280 } 1281 1282 /* 1283 * When in backup state, af indicates whether to reset the master down timer 1284 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1285 */ 1286 static void 1287 carp_setrun(struct carp_softc *sc, sa_family_t af) 1288 { 1289 struct timeval tv; 1290 1291 CARP_LOCK_ASSERT(sc); 1292 1293 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1294 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1295 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0)) 1296 return; 1297 1298 switch (sc->sc_state) { 1299 case INIT: 1300 carp_set_state(sc, BACKUP, "initialization complete"); 1301 carp_setrun(sc, 0); 1302 break; 1303 case BACKUP: 1304 callout_stop(&sc->sc_ad_tmo); 1305 tv.tv_sec = 3 * sc->sc_advbase; 1306 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1307 switch (af) { 1308 #ifdef INET 1309 case AF_INET: 1310 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1311 carp_master_down, sc); 1312 break; 1313 #endif 1314 #ifdef INET6 1315 case AF_INET6: 1316 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1317 carp_master_down, sc); 1318 break; 1319 #endif 1320 default: 1321 #ifdef INET 1322 if (sc->sc_naddrs) 1323 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1324 carp_master_down, sc); 1325 #endif 1326 #ifdef INET6 1327 if (sc->sc_naddrs6) 1328 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1329 carp_master_down, sc); 1330 #endif 1331 break; 1332 } 1333 break; 1334 case MASTER: 1335 tv.tv_sec = sc->sc_advbase; 1336 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1337 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1338 carp_send_ad, sc); 1339 break; 1340 } 1341 } 1342 1343 /* 1344 * Setup multicast structures. 1345 */ 1346 static int 1347 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1348 { 1349 struct ifnet *ifp = cif->cif_ifp; 1350 int error = 0; 1351 1352 switch (sa) { 1353 #ifdef INET 1354 case AF_INET: 1355 { 1356 struct ip_moptions *imo = &cif->cif_imo; 1357 struct in_addr addr; 1358 1359 if (imo->imo_membership) 1360 return (0); 1361 1362 imo->imo_membership = (struct in_multi **)malloc( 1363 (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, 1364 M_WAITOK); 1365 imo->imo_mfilters = NULL; 1366 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS; 1367 imo->imo_multicast_vif = -1; 1368 1369 addr.s_addr = htonl(INADDR_CARP_GROUP); 1370 if ((error = in_joingroup(ifp, &addr, NULL, 1371 &imo->imo_membership[0])) != 0) { 1372 free(imo->imo_membership, M_CARP); 1373 break; 1374 } 1375 imo->imo_num_memberships++; 1376 imo->imo_multicast_ifp = ifp; 1377 imo->imo_multicast_ttl = CARP_DFLTTL; 1378 imo->imo_multicast_loop = 0; 1379 break; 1380 } 1381 #endif 1382 #ifdef INET6 1383 case AF_INET6: 1384 { 1385 struct ip6_moptions *im6o = &cif->cif_im6o; 1386 struct in6_addr in6; 1387 struct in6_multi *in6m; 1388 1389 if (im6o->im6o_membership) 1390 return (0); 1391 1392 im6o->im6o_membership = (struct in6_multi **)malloc( 1393 (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, 1394 M_ZERO | M_WAITOK); 1395 im6o->im6o_mfilters = NULL; 1396 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; 1397 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1398 im6o->im6o_multicast_ifp = ifp; 1399 1400 /* Join IPv6 CARP multicast group. */ 1401 bzero(&in6, sizeof(in6)); 1402 in6.s6_addr16[0] = htons(0xff02); 1403 in6.s6_addr8[15] = 0x12; 1404 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1405 free(im6o->im6o_membership, M_CARP); 1406 break; 1407 } 1408 in6m = NULL; 1409 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { 1410 free(im6o->im6o_membership, M_CARP); 1411 break; 1412 } 1413 im6o->im6o_membership[0] = in6m; 1414 im6o->im6o_num_memberships++; 1415 1416 /* Join solicited multicast address. */ 1417 bzero(&in6, sizeof(in6)); 1418 in6.s6_addr16[0] = htons(0xff02); 1419 in6.s6_addr32[1] = 0; 1420 in6.s6_addr32[2] = htonl(1); 1421 in6.s6_addr32[3] = 0; 1422 in6.s6_addr8[12] = 0xff; 1423 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1424 in6_mc_leave(im6o->im6o_membership[0], NULL); 1425 free(im6o->im6o_membership, M_CARP); 1426 break; 1427 } 1428 in6m = NULL; 1429 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) { 1430 in6_mc_leave(im6o->im6o_membership[0], NULL); 1431 free(im6o->im6o_membership, M_CARP); 1432 break; 1433 } 1434 im6o->im6o_membership[1] = in6m; 1435 im6o->im6o_num_memberships++; 1436 break; 1437 } 1438 #endif 1439 } 1440 1441 return (error); 1442 } 1443 1444 /* 1445 * Free multicast structures. 1446 */ 1447 static void 1448 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1449 { 1450 1451 sx_assert(&carp_sx, SA_XLOCKED); 1452 1453 switch (sa) { 1454 #ifdef INET 1455 case AF_INET: 1456 if (cif->cif_naddrs == 0) { 1457 struct ip_moptions *imo = &cif->cif_imo; 1458 1459 in_leavegroup(imo->imo_membership[0], NULL); 1460 KASSERT(imo->imo_mfilters == NULL, 1461 ("%s: imo_mfilters != NULL", __func__)); 1462 free(imo->imo_membership, M_CARP); 1463 imo->imo_membership = NULL; 1464 1465 } 1466 break; 1467 #endif 1468 #ifdef INET6 1469 case AF_INET6: 1470 if (cif->cif_naddrs6 == 0) { 1471 struct ip6_moptions *im6o = &cif->cif_im6o; 1472 1473 in6_mc_leave(im6o->im6o_membership[0], NULL); 1474 in6_mc_leave(im6o->im6o_membership[1], NULL); 1475 KASSERT(im6o->im6o_mfilters == NULL, 1476 ("%s: im6o_mfilters != NULL", __func__)); 1477 free(im6o->im6o_membership, M_CARP); 1478 im6o->im6o_membership = NULL; 1479 } 1480 break; 1481 #endif 1482 } 1483 } 1484 1485 int 1486 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1487 { 1488 struct m_tag *mtag; 1489 struct carp_softc *sc; 1490 1491 if (!sa) 1492 return (0); 1493 1494 switch (sa->sa_family) { 1495 #ifdef INET 1496 case AF_INET: 1497 break; 1498 #endif 1499 #ifdef INET6 1500 case AF_INET6: 1501 break; 1502 #endif 1503 default: 1504 return (0); 1505 } 1506 1507 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1508 if (mtag == NULL) 1509 return (0); 1510 1511 bcopy(mtag + 1, &sc, sizeof(sc)); 1512 1513 /* Set the source MAC address to the Virtual Router MAC Address. */ 1514 switch (ifp->if_type) { 1515 case IFT_ETHER: 1516 case IFT_BRIDGE: 1517 case IFT_L2VLAN: { 1518 struct ether_header *eh; 1519 1520 eh = mtod(m, struct ether_header *); 1521 eh->ether_shost[0] = 0; 1522 eh->ether_shost[1] = 0; 1523 eh->ether_shost[2] = 0x5e; 1524 eh->ether_shost[3] = 0; 1525 eh->ether_shost[4] = 1; 1526 eh->ether_shost[5] = sc->sc_vhid; 1527 } 1528 break; 1529 case IFT_FDDI: { 1530 struct fddi_header *fh; 1531 1532 fh = mtod(m, struct fddi_header *); 1533 fh->fddi_shost[0] = 0; 1534 fh->fddi_shost[1] = 0; 1535 fh->fddi_shost[2] = 0x5e; 1536 fh->fddi_shost[3] = 0; 1537 fh->fddi_shost[4] = 1; 1538 fh->fddi_shost[5] = sc->sc_vhid; 1539 } 1540 break; 1541 default: 1542 printf("%s: carp is not supported for the %d interface type\n", 1543 ifp->if_xname, ifp->if_type); 1544 return (EOPNOTSUPP); 1545 } 1546 1547 return (0); 1548 } 1549 1550 static struct carp_softc* 1551 carp_alloc(struct ifnet *ifp) 1552 { 1553 struct carp_softc *sc; 1554 struct carp_if *cif; 1555 1556 sx_assert(&carp_sx, SA_XLOCKED); 1557 1558 if ((cif = ifp->if_carp) == NULL) 1559 cif = carp_alloc_if(ifp); 1560 1561 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1562 1563 sc->sc_advbase = CARP_DFLTINTV; 1564 sc->sc_vhid = -1; /* required setting */ 1565 sc->sc_init_counter = 1; 1566 sc->sc_state = INIT; 1567 1568 sc->sc_ifasiz = sizeof(struct ifaddr *); 1569 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1570 sc->sc_carpdev = ifp; 1571 1572 CARP_LOCK_INIT(sc); 1573 #ifdef INET 1574 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1575 #endif 1576 #ifdef INET6 1577 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1578 #endif 1579 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1580 1581 CIF_LOCK(cif); 1582 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1583 CIF_UNLOCK(cif); 1584 1585 mtx_lock(&carp_mtx); 1586 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1587 mtx_unlock(&carp_mtx); 1588 1589 return (sc); 1590 } 1591 1592 static void 1593 carp_grow_ifas(struct carp_softc *sc) 1594 { 1595 struct ifaddr **new; 1596 1597 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1598 CARP_LOCK(sc); 1599 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1600 free(sc->sc_ifas, M_CARP); 1601 sc->sc_ifas = new; 1602 sc->sc_ifasiz *= 2; 1603 CARP_UNLOCK(sc); 1604 } 1605 1606 static void 1607 carp_destroy(struct carp_softc *sc) 1608 { 1609 struct ifnet *ifp = sc->sc_carpdev; 1610 struct carp_if *cif = ifp->if_carp; 1611 1612 sx_assert(&carp_sx, SA_XLOCKED); 1613 1614 if (sc->sc_suppress) 1615 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1616 CARP_UNLOCK(sc); 1617 1618 CIF_LOCK(cif); 1619 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1620 CIF_UNLOCK(cif); 1621 1622 mtx_lock(&carp_mtx); 1623 LIST_REMOVE(sc, sc_next); 1624 mtx_unlock(&carp_mtx); 1625 1626 callout_drain(&sc->sc_ad_tmo); 1627 #ifdef INET 1628 callout_drain(&sc->sc_md_tmo); 1629 #endif 1630 #ifdef INET6 1631 callout_drain(&sc->sc_md6_tmo); 1632 #endif 1633 CARP_LOCK_DESTROY(sc); 1634 1635 free(sc->sc_ifas, M_CARP); 1636 free(sc, M_CARP); 1637 } 1638 1639 static struct carp_if* 1640 carp_alloc_if(struct ifnet *ifp) 1641 { 1642 struct carp_if *cif; 1643 int error; 1644 1645 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1646 1647 if ((error = ifpromisc(ifp, 1)) != 0) 1648 printf("%s: ifpromisc(%s) failed: %d\n", 1649 __func__, ifp->if_xname, error); 1650 else 1651 cif->cif_flags |= CIF_PROMISC; 1652 1653 CIF_LOCK_INIT(cif); 1654 cif->cif_ifp = ifp; 1655 TAILQ_INIT(&cif->cif_vrs); 1656 1657 IF_ADDR_WLOCK(ifp); 1658 ifp->if_carp = cif; 1659 if_ref(ifp); 1660 IF_ADDR_WUNLOCK(ifp); 1661 1662 return (cif); 1663 } 1664 1665 static void 1666 carp_free_if(struct carp_if *cif) 1667 { 1668 struct ifnet *ifp = cif->cif_ifp; 1669 1670 CIF_LOCK_ASSERT(cif); 1671 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1672 __func__)); 1673 1674 IF_ADDR_WLOCK(ifp); 1675 ifp->if_carp = NULL; 1676 IF_ADDR_WUNLOCK(ifp); 1677 1678 CIF_LOCK_DESTROY(cif); 1679 1680 if (cif->cif_flags & CIF_PROMISC) 1681 ifpromisc(ifp, 0); 1682 if_rele(ifp); 1683 1684 free(cif, M_CARP); 1685 } 1686 1687 static void 1688 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1689 { 1690 1691 CARP_LOCK(sc); 1692 carpr->carpr_state = sc->sc_state; 1693 carpr->carpr_vhid = sc->sc_vhid; 1694 carpr->carpr_advbase = sc->sc_advbase; 1695 carpr->carpr_advskew = sc->sc_advskew; 1696 if (priv) 1697 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1698 else 1699 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1700 CARP_UNLOCK(sc); 1701 } 1702 1703 int 1704 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1705 { 1706 struct carpreq carpr; 1707 struct ifnet *ifp; 1708 struct carp_softc *sc = NULL; 1709 int error = 0, locked = 0; 1710 1711 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1712 return (error); 1713 1714 ifp = ifunit_ref(ifr->ifr_name); 1715 if (ifp == NULL) 1716 return (ENXIO); 1717 1718 switch (ifp->if_type) { 1719 case IFT_ETHER: 1720 case IFT_L2VLAN: 1721 case IFT_BRIDGE: 1722 case IFT_FDDI: 1723 break; 1724 default: 1725 error = EOPNOTSUPP; 1726 goto out; 1727 } 1728 1729 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1730 error = EADDRNOTAVAIL; 1731 goto out; 1732 } 1733 1734 sx_xlock(&carp_sx); 1735 switch (cmd) { 1736 case SIOCSVH: 1737 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1738 break; 1739 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1740 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1741 error = EINVAL; 1742 break; 1743 } 1744 1745 if (ifp->if_carp) { 1746 IFNET_FOREACH_CARP(ifp, sc) 1747 if (sc->sc_vhid == carpr.carpr_vhid) 1748 break; 1749 } 1750 if (sc == NULL) { 1751 sc = carp_alloc(ifp); 1752 CARP_LOCK(sc); 1753 sc->sc_vhid = carpr.carpr_vhid; 1754 LLADDR(&sc->sc_addr)[0] = 0; 1755 LLADDR(&sc->sc_addr)[1] = 0; 1756 LLADDR(&sc->sc_addr)[2] = 0x5e; 1757 LLADDR(&sc->sc_addr)[3] = 0; 1758 LLADDR(&sc->sc_addr)[4] = 1; 1759 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1760 } else 1761 CARP_LOCK(sc); 1762 locked = 1; 1763 if (carpr.carpr_advbase > 0) { 1764 if (carpr.carpr_advbase > 255 || 1765 carpr.carpr_advbase < CARP_DFLTINTV) { 1766 error = EINVAL; 1767 break; 1768 } 1769 sc->sc_advbase = carpr.carpr_advbase; 1770 } 1771 if (carpr.carpr_advskew >= 255) { 1772 error = EINVAL; 1773 break; 1774 } 1775 sc->sc_advskew = carpr.carpr_advskew; 1776 if (carpr.carpr_key[0] != '\0') { 1777 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1778 carp_hmac_prepare(sc); 1779 } 1780 if (sc->sc_state != INIT && 1781 carpr.carpr_state != sc->sc_state) { 1782 switch (carpr.carpr_state) { 1783 case BACKUP: 1784 callout_stop(&sc->sc_ad_tmo); 1785 carp_set_state(sc, BACKUP, 1786 "user requested via ifconfig"); 1787 carp_setrun(sc, 0); 1788 carp_delroute(sc); 1789 break; 1790 case MASTER: 1791 carp_master_down_locked(sc, 1792 "user requested via ifconfig"); 1793 break; 1794 default: 1795 break; 1796 } 1797 } 1798 break; 1799 1800 case SIOCGVH: 1801 { 1802 int priveleged; 1803 1804 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1805 error = EINVAL; 1806 break; 1807 } 1808 if (carpr.carpr_count < 1) { 1809 error = EMSGSIZE; 1810 break; 1811 } 1812 if (ifp->if_carp == NULL) { 1813 error = ENOENT; 1814 break; 1815 } 1816 1817 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1818 if (carpr.carpr_vhid != 0) { 1819 IFNET_FOREACH_CARP(ifp, sc) 1820 if (sc->sc_vhid == carpr.carpr_vhid) 1821 break; 1822 if (sc == NULL) { 1823 error = ENOENT; 1824 break; 1825 } 1826 carp_carprcp(&carpr, sc, priveleged); 1827 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1828 sizeof(carpr)); 1829 } else { 1830 int i, count; 1831 1832 count = 0; 1833 IFNET_FOREACH_CARP(ifp, sc) 1834 count++; 1835 1836 if (count > carpr.carpr_count) { 1837 CIF_UNLOCK(ifp->if_carp); 1838 error = EMSGSIZE; 1839 break; 1840 } 1841 1842 i = 0; 1843 IFNET_FOREACH_CARP(ifp, sc) { 1844 carp_carprcp(&carpr, sc, priveleged); 1845 carpr.carpr_count = count; 1846 error = copyout(&carpr, 1847 (caddr_t)ifr_data_get_ptr(ifr) + 1848 (i * sizeof(carpr)), sizeof(carpr)); 1849 if (error) { 1850 CIF_UNLOCK(ifp->if_carp); 1851 break; 1852 } 1853 i++; 1854 } 1855 } 1856 break; 1857 } 1858 default: 1859 error = EINVAL; 1860 } 1861 sx_xunlock(&carp_sx); 1862 1863 out: 1864 if (locked) 1865 CARP_UNLOCK(sc); 1866 if_rele(ifp); 1867 1868 return (error); 1869 } 1870 1871 static int 1872 carp_get_vhid(struct ifaddr *ifa) 1873 { 1874 1875 if (ifa == NULL || ifa->ifa_carp == NULL) 1876 return (0); 1877 1878 return (ifa->ifa_carp->sc_vhid); 1879 } 1880 1881 int 1882 carp_attach(struct ifaddr *ifa, int vhid) 1883 { 1884 struct ifnet *ifp = ifa->ifa_ifp; 1885 struct carp_if *cif = ifp->if_carp; 1886 struct carp_softc *sc; 1887 int index, error; 1888 1889 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1890 1891 switch (ifa->ifa_addr->sa_family) { 1892 #ifdef INET 1893 case AF_INET: 1894 #endif 1895 #ifdef INET6 1896 case AF_INET6: 1897 #endif 1898 break; 1899 default: 1900 return (EPROTOTYPE); 1901 } 1902 1903 sx_xlock(&carp_sx); 1904 if (ifp->if_carp == NULL) { 1905 sx_xunlock(&carp_sx); 1906 return (ENOPROTOOPT); 1907 } 1908 1909 IFNET_FOREACH_CARP(ifp, sc) 1910 if (sc->sc_vhid == vhid) 1911 break; 1912 if (sc == NULL) { 1913 sx_xunlock(&carp_sx); 1914 return (ENOENT); 1915 } 1916 1917 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1918 if (error) { 1919 CIF_FREE(cif); 1920 sx_xunlock(&carp_sx); 1921 return (error); 1922 } 1923 1924 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1925 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1926 carp_grow_ifas(sc); 1927 1928 switch (ifa->ifa_addr->sa_family) { 1929 #ifdef INET 1930 case AF_INET: 1931 cif->cif_naddrs++; 1932 sc->sc_naddrs++; 1933 break; 1934 #endif 1935 #ifdef INET6 1936 case AF_INET6: 1937 cif->cif_naddrs6++; 1938 sc->sc_naddrs6++; 1939 break; 1940 #endif 1941 } 1942 1943 ifa_ref(ifa); 1944 1945 CARP_LOCK(sc); 1946 sc->sc_ifas[index - 1] = ifa; 1947 ifa->ifa_carp = sc; 1948 carp_hmac_prepare(sc); 1949 carp_sc_state(sc); 1950 CARP_UNLOCK(sc); 1951 1952 sx_xunlock(&carp_sx); 1953 1954 return (0); 1955 } 1956 1957 void 1958 carp_detach(struct ifaddr *ifa, bool keep_cif) 1959 { 1960 struct ifnet *ifp = ifa->ifa_ifp; 1961 struct carp_if *cif = ifp->if_carp; 1962 struct carp_softc *sc = ifa->ifa_carp; 1963 int i, index; 1964 1965 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1966 1967 sx_xlock(&carp_sx); 1968 1969 CARP_LOCK(sc); 1970 /* Shift array. */ 1971 index = sc->sc_naddrs + sc->sc_naddrs6; 1972 for (i = 0; i < index; i++) 1973 if (sc->sc_ifas[i] == ifa) 1974 break; 1975 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1976 for (; i < index - 1; i++) 1977 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 1978 sc->sc_ifas[index - 1] = NULL; 1979 1980 switch (ifa->ifa_addr->sa_family) { 1981 #ifdef INET 1982 case AF_INET: 1983 cif->cif_naddrs--; 1984 sc->sc_naddrs--; 1985 break; 1986 #endif 1987 #ifdef INET6 1988 case AF_INET6: 1989 cif->cif_naddrs6--; 1990 sc->sc_naddrs6--; 1991 break; 1992 #endif 1993 } 1994 1995 carp_ifa_delroute(ifa); 1996 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 1997 1998 ifa->ifa_carp = NULL; 1999 ifa_free(ifa); 2000 2001 carp_hmac_prepare(sc); 2002 carp_sc_state(sc); 2003 2004 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2005 carp_destroy(sc); 2006 else 2007 CARP_UNLOCK(sc); 2008 2009 if (!keep_cif) 2010 CIF_FREE(cif); 2011 2012 sx_xunlock(&carp_sx); 2013 } 2014 2015 static void 2016 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2017 { 2018 2019 CARP_LOCK_ASSERT(sc); 2020 2021 if (sc->sc_state != state) { 2022 const char *carp_states[] = { CARP_STATES }; 2023 char subsys[IFNAMSIZ+5]; 2024 2025 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2026 sc->sc_carpdev->if_xname); 2027 2028 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2029 carp_states[sc->sc_state], carp_states[state], reason); 2030 2031 sc->sc_state = state; 2032 2033 devctl_notify("CARP", subsys, carp_states[state], NULL); 2034 } 2035 } 2036 2037 static void 2038 carp_linkstate(struct ifnet *ifp) 2039 { 2040 struct carp_softc *sc; 2041 2042 CIF_LOCK(ifp->if_carp); 2043 IFNET_FOREACH_CARP(ifp, sc) { 2044 CARP_LOCK(sc); 2045 carp_sc_state(sc); 2046 CARP_UNLOCK(sc); 2047 } 2048 CIF_UNLOCK(ifp->if_carp); 2049 } 2050 2051 static void 2052 carp_sc_state(struct carp_softc *sc) 2053 { 2054 2055 CARP_LOCK_ASSERT(sc); 2056 2057 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2058 !(sc->sc_carpdev->if_flags & IFF_UP)) { 2059 callout_stop(&sc->sc_ad_tmo); 2060 #ifdef INET 2061 callout_stop(&sc->sc_md_tmo); 2062 #endif 2063 #ifdef INET6 2064 callout_stop(&sc->sc_md6_tmo); 2065 #endif 2066 carp_set_state(sc, INIT, "hardware interface down"); 2067 carp_setrun(sc, 0); 2068 if (!sc->sc_suppress) 2069 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2070 sc->sc_suppress = 1; 2071 } else { 2072 carp_set_state(sc, INIT, "hardware interface up"); 2073 carp_setrun(sc, 0); 2074 if (sc->sc_suppress) 2075 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2076 sc->sc_suppress = 0; 2077 } 2078 } 2079 2080 static void 2081 carp_demote_adj(int adj, char *reason) 2082 { 2083 atomic_add_int(&V_carp_demotion, adj); 2084 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2085 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2086 } 2087 2088 static int 2089 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2090 { 2091 int new, error; 2092 2093 new = V_carp_demotion; 2094 error = sysctl_handle_int(oidp, &new, 0, req); 2095 if (error || !req->newptr) 2096 return (error); 2097 2098 carp_demote_adj(new, "sysctl"); 2099 2100 return (0); 2101 } 2102 2103 #ifdef INET 2104 extern struct domain inetdomain; 2105 static struct protosw in_carp_protosw = { 2106 .pr_type = SOCK_RAW, 2107 .pr_domain = &inetdomain, 2108 .pr_protocol = IPPROTO_CARP, 2109 .pr_flags = PR_ATOMIC|PR_ADDR, 2110 .pr_input = carp_input, 2111 .pr_output = rip_output, 2112 .pr_ctloutput = rip_ctloutput, 2113 .pr_usrreqs = &rip_usrreqs 2114 }; 2115 #endif 2116 2117 #ifdef INET6 2118 extern struct domain inet6domain; 2119 static struct protosw in6_carp_protosw = { 2120 .pr_type = SOCK_RAW, 2121 .pr_domain = &inet6domain, 2122 .pr_protocol = IPPROTO_CARP, 2123 .pr_flags = PR_ATOMIC|PR_ADDR, 2124 .pr_input = carp6_input, 2125 .pr_output = rip6_output, 2126 .pr_ctloutput = rip6_ctloutput, 2127 .pr_usrreqs = &rip6_usrreqs 2128 }; 2129 #endif 2130 2131 static void 2132 carp_mod_cleanup(void) 2133 { 2134 2135 #ifdef INET 2136 if (proto_reg[CARP_INET] == 0) { 2137 (void)ipproto_unregister(IPPROTO_CARP); 2138 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2139 proto_reg[CARP_INET] = -1; 2140 } 2141 carp_iamatch_p = NULL; 2142 #endif 2143 #ifdef INET6 2144 if (proto_reg[CARP_INET6] == 0) { 2145 (void)ip6proto_unregister(IPPROTO_CARP); 2146 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2147 proto_reg[CARP_INET6] = -1; 2148 } 2149 carp_iamatch6_p = NULL; 2150 carp_macmatch6_p = NULL; 2151 #endif 2152 carp_ioctl_p = NULL; 2153 carp_attach_p = NULL; 2154 carp_detach_p = NULL; 2155 carp_get_vhid_p = NULL; 2156 carp_linkstate_p = NULL; 2157 carp_forus_p = NULL; 2158 carp_output_p = NULL; 2159 carp_demote_adj_p = NULL; 2160 carp_master_p = NULL; 2161 mtx_unlock(&carp_mtx); 2162 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2163 mtx_destroy(&carp_mtx); 2164 sx_destroy(&carp_sx); 2165 } 2166 2167 static int 2168 carp_mod_load(void) 2169 { 2170 int err; 2171 2172 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2173 sx_init(&carp_sx, "carp_sx"); 2174 LIST_INIT(&carp_list); 2175 carp_get_vhid_p = carp_get_vhid; 2176 carp_forus_p = carp_forus; 2177 carp_output_p = carp_output; 2178 carp_linkstate_p = carp_linkstate; 2179 carp_ioctl_p = carp_ioctl; 2180 carp_attach_p = carp_attach; 2181 carp_detach_p = carp_detach; 2182 carp_demote_adj_p = carp_demote_adj; 2183 carp_master_p = carp_master; 2184 #ifdef INET6 2185 carp_iamatch6_p = carp_iamatch6; 2186 carp_macmatch6_p = carp_macmatch6; 2187 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2188 (struct protosw *)&in6_carp_protosw); 2189 if (proto_reg[CARP_INET6]) { 2190 printf("carp: error %d attaching to PF_INET6\n", 2191 proto_reg[CARP_INET6]); 2192 carp_mod_cleanup(); 2193 return (proto_reg[CARP_INET6]); 2194 } 2195 err = ip6proto_register(IPPROTO_CARP); 2196 if (err) { 2197 printf("carp: error %d registering with INET6\n", err); 2198 carp_mod_cleanup(); 2199 return (err); 2200 } 2201 #endif 2202 #ifdef INET 2203 carp_iamatch_p = carp_iamatch; 2204 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2205 if (proto_reg[CARP_INET]) { 2206 printf("carp: error %d attaching to PF_INET\n", 2207 proto_reg[CARP_INET]); 2208 carp_mod_cleanup(); 2209 return (proto_reg[CARP_INET]); 2210 } 2211 err = ipproto_register(IPPROTO_CARP); 2212 if (err) { 2213 printf("carp: error %d registering with INET\n", err); 2214 carp_mod_cleanup(); 2215 return (err); 2216 } 2217 #endif 2218 return (0); 2219 } 2220 2221 static int 2222 carp_modevent(module_t mod, int type, void *data) 2223 { 2224 switch (type) { 2225 case MOD_LOAD: 2226 return carp_mod_load(); 2227 /* NOTREACHED */ 2228 case MOD_UNLOAD: 2229 mtx_lock(&carp_mtx); 2230 if (LIST_EMPTY(&carp_list)) 2231 carp_mod_cleanup(); 2232 else { 2233 mtx_unlock(&carp_mtx); 2234 return (EBUSY); 2235 } 2236 break; 2237 2238 default: 2239 return (EINVAL); 2240 } 2241 2242 return (0); 2243 } 2244 2245 static moduledata_t carp_mod = { 2246 "carp", 2247 carp_modevent, 2248 0 2249 }; 2250 2251 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2252