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/if.h> 59 #include <net/if_var.h> 60 #include <net/if_dl.h> 61 #include <net/if_llatbl.h> 62 #include <net/if_types.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 VNET_DEFINE_STATIC(int, carp_allow) = 1; 191 #define V_carp_allow VNET(carp_allow) 192 193 /* Set DSCP in outgoing CARP packets. */ 194 VNET_DEFINE_STATIC(int, carp_dscp) = 56; 195 #define V_carp_dscp VNET(carp_dscp) 196 197 /* Preempt slower nodes. */ 198 VNET_DEFINE_STATIC(int, carp_preempt) = 0; 199 #define V_carp_preempt VNET(carp_preempt) 200 201 /* Log level. */ 202 VNET_DEFINE_STATIC(int, carp_log) = 1; 203 #define V_carp_log VNET(carp_log) 204 205 /* Global advskew demotion. */ 206 VNET_DEFINE_STATIC(int, carp_demotion) = 0; 207 #define V_carp_demotion VNET(carp_demotion) 208 209 /* Send error demotion factor. */ 210 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW; 211 #define V_carp_senderr_adj VNET(carp_senderr_adj) 212 213 /* Iface down demotion factor. */ 214 VNET_DEFINE_STATIC(int, carp_ifdown_adj) = CARP_MAXSKEW; 215 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 216 217 static int carp_allow_sysctl(SYSCTL_HANDLER_ARGS); 218 static int carp_dscp_sysctl(SYSCTL_HANDLER_ARGS); 219 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 220 221 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW, 0, "CARP"); 222 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 223 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_allow_sysctl, "I", 224 "Accept incoming CARP packets"); 225 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp, 226 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_dscp_sysctl, "I", 227 "DSCP value for carp packets"); 228 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 229 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 230 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 231 &VNET_NAME(carp_log), 0, "CARP log level"); 232 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 233 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 234 0, 0, carp_demote_adj_sysctl, "I", 235 "Adjust demotion factor (skew of advskew)"); 236 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 237 CTLFLAG_VNET | CTLFLAG_RW, 238 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 239 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 240 CTLFLAG_VNET | CTLFLAG_RW, 241 &VNET_NAME(carp_ifdown_adj), 0, 242 "Interface down demotion factor adjustment"); 243 244 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 245 VNET_PCPUSTAT_SYSINIT(carpstats); 246 VNET_PCPUSTAT_SYSUNINIT(carpstats); 247 248 #define CARPSTATS_ADD(name, val) \ 249 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 250 sizeof(uint64_t)], (val)) 251 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 252 253 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 254 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 255 256 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 257 NULL, MTX_DEF) 258 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 259 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 260 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 261 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 262 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 263 NULL, MTX_DEF) 264 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 265 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 266 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 267 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 268 #define CIF_FREE(cif) do { \ 269 CIF_LOCK(cif); \ 270 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 271 carp_free_if(cif); \ 272 else \ 273 CIF_UNLOCK(cif); \ 274 } while (0) 275 276 #define CARP_LOG(...) do { \ 277 if (V_carp_log > 0) \ 278 log(LOG_INFO, "carp: " __VA_ARGS__); \ 279 } while (0) 280 281 #define CARP_DEBUG(...) do { \ 282 if (V_carp_log > 1) \ 283 log(LOG_DEBUG, __VA_ARGS__); \ 284 } while (0) 285 286 #define IFNET_FOREACH_IFA(ifp, ifa) \ 287 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 288 if ((ifa)->ifa_carp != NULL) 289 290 #define CARP_FOREACH_IFA(sc, ifa) \ 291 CARP_LOCK_ASSERT(sc); \ 292 for (int _i = 0; \ 293 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 294 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 295 ++_i) 296 297 #define IFNET_FOREACH_CARP(ifp, sc) \ 298 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 299 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 300 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 301 302 #define DEMOTE_ADVSKEW(sc) \ 303 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 304 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) 305 306 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 307 static struct carp_softc 308 *carp_alloc(struct ifnet *); 309 static void carp_destroy(struct carp_softc *); 310 static struct carp_if 311 *carp_alloc_if(struct ifnet *); 312 static void carp_free_if(struct carp_if *); 313 static void carp_set_state(struct carp_softc *, int, const char* reason); 314 static void carp_sc_state(struct carp_softc *); 315 static void carp_setrun(struct carp_softc *, sa_family_t); 316 static void carp_master_down(void *); 317 static void carp_master_down_locked(struct carp_softc *, 318 const char* reason); 319 static void carp_send_ad(void *); 320 static void carp_send_ad_locked(struct carp_softc *); 321 static void carp_addroute(struct carp_softc *); 322 static void carp_ifa_addroute(struct ifaddr *); 323 static void carp_delroute(struct carp_softc *); 324 static void carp_ifa_delroute(struct ifaddr *); 325 static void carp_send_ad_all(void *, int); 326 static void carp_demote_adj(int, char *); 327 328 static LIST_HEAD(, carp_softc) carp_list; 329 static struct mtx carp_mtx; 330 static struct sx carp_sx; 331 static struct task carp_sendall_task = 332 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 333 334 static void 335 carp_hmac_prepare(struct carp_softc *sc) 336 { 337 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 338 uint8_t vhid = sc->sc_vhid & 0xff; 339 struct ifaddr *ifa; 340 int i, found; 341 #ifdef INET 342 struct in_addr last, cur, in; 343 #endif 344 #ifdef INET6 345 struct in6_addr last6, cur6, in6; 346 #endif 347 348 CARP_LOCK_ASSERT(sc); 349 350 /* Compute ipad from key. */ 351 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 352 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 353 for (i = 0; i < sizeof(sc->sc_pad); i++) 354 sc->sc_pad[i] ^= 0x36; 355 356 /* Precompute first part of inner hash. */ 357 SHA1Init(&sc->sc_sha1); 358 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 359 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 360 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 361 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 362 #ifdef INET 363 cur.s_addr = 0; 364 do { 365 found = 0; 366 last = cur; 367 cur.s_addr = 0xffffffff; 368 CARP_FOREACH_IFA(sc, ifa) { 369 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 370 if (ifa->ifa_addr->sa_family == AF_INET && 371 ntohl(in.s_addr) > ntohl(last.s_addr) && 372 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 373 cur.s_addr = in.s_addr; 374 found++; 375 } 376 } 377 if (found) 378 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 379 } while (found); 380 #endif /* INET */ 381 #ifdef INET6 382 memset(&cur6, 0, sizeof(cur6)); 383 do { 384 found = 0; 385 last6 = cur6; 386 memset(&cur6, 0xff, sizeof(cur6)); 387 CARP_FOREACH_IFA(sc, ifa) { 388 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 389 if (IN6_IS_SCOPE_EMBED(&in6)) 390 in6.s6_addr16[1] = 0; 391 if (ifa->ifa_addr->sa_family == AF_INET6 && 392 memcmp(&in6, &last6, sizeof(in6)) > 0 && 393 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 394 cur6 = in6; 395 found++; 396 } 397 } 398 if (found) 399 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 400 } while (found); 401 #endif /* INET6 */ 402 403 /* convert ipad to opad */ 404 for (i = 0; i < sizeof(sc->sc_pad); i++) 405 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 406 } 407 408 static void 409 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 410 unsigned char md[20]) 411 { 412 SHA1_CTX sha1ctx; 413 414 CARP_LOCK_ASSERT(sc); 415 416 /* fetch first half of inner hash */ 417 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 418 419 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 420 SHA1Final(md, &sha1ctx); 421 422 /* outer hash */ 423 SHA1Init(&sha1ctx); 424 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 425 SHA1Update(&sha1ctx, md, 20); 426 SHA1Final(md, &sha1ctx); 427 } 428 429 static int 430 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 431 unsigned char md[20]) 432 { 433 unsigned char md2[20]; 434 435 CARP_LOCK_ASSERT(sc); 436 437 carp_hmac_generate(sc, counter, md2); 438 439 return (bcmp(md, md2, sizeof(md2))); 440 } 441 442 /* 443 * process input packet. 444 * we have rearranged checks order compared to the rfc, 445 * but it seems more efficient this way or not possible otherwise. 446 */ 447 #ifdef INET 448 int 449 carp_input(struct mbuf **mp, int *offp, int proto) 450 { 451 struct mbuf *m = *mp; 452 struct ip *ip = mtod(m, struct ip *); 453 struct carp_header *ch; 454 int iplen, len; 455 456 iplen = *offp; 457 *mp = NULL; 458 459 CARPSTATS_INC(carps_ipackets); 460 461 if (!V_carp_allow) { 462 m_freem(m); 463 return (IPPROTO_DONE); 464 } 465 466 /* verify that the IP TTL is 255. */ 467 if (ip->ip_ttl != CARP_DFLTTL) { 468 CARPSTATS_INC(carps_badttl); 469 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 470 ip->ip_ttl, 471 m->m_pkthdr.rcvif->if_xname); 472 m_freem(m); 473 return (IPPROTO_DONE); 474 } 475 476 iplen = ip->ip_hl << 2; 477 478 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 479 CARPSTATS_INC(carps_badlen); 480 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 481 "on %s\n", __func__, m->m_len - sizeof(struct ip), 482 m->m_pkthdr.rcvif->if_xname); 483 m_freem(m); 484 return (IPPROTO_DONE); 485 } 486 487 if (iplen + sizeof(*ch) < m->m_len) { 488 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 489 CARPSTATS_INC(carps_hdrops); 490 CARP_DEBUG("%s: pullup failed\n", __func__); 491 return (IPPROTO_DONE); 492 } 493 ip = mtod(m, struct ip *); 494 } 495 ch = (struct carp_header *)((char *)ip + iplen); 496 497 /* 498 * verify that the received packet length is 499 * equal to the CARP header 500 */ 501 len = iplen + sizeof(*ch); 502 if (len > m->m_pkthdr.len) { 503 CARPSTATS_INC(carps_badlen); 504 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 505 m->m_pkthdr.len, 506 m->m_pkthdr.rcvif->if_xname); 507 m_freem(m); 508 return (IPPROTO_DONE); 509 } 510 511 if ((m = m_pullup(m, len)) == NULL) { 512 CARPSTATS_INC(carps_hdrops); 513 return (IPPROTO_DONE); 514 } 515 ip = mtod(m, struct ip *); 516 ch = (struct carp_header *)((char *)ip + iplen); 517 518 /* verify the CARP checksum */ 519 m->m_data += iplen; 520 if (in_cksum(m, len - iplen)) { 521 CARPSTATS_INC(carps_badsum); 522 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 523 m->m_pkthdr.rcvif->if_xname); 524 m_freem(m); 525 return (IPPROTO_DONE); 526 } 527 m->m_data -= iplen; 528 529 carp_input_c(m, ch, AF_INET); 530 return (IPPROTO_DONE); 531 } 532 #endif 533 534 #ifdef INET6 535 int 536 carp6_input(struct mbuf **mp, int *offp, int proto) 537 { 538 struct mbuf *m = *mp; 539 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 540 struct carp_header *ch; 541 u_int len; 542 543 CARPSTATS_INC(carps_ipackets6); 544 545 if (!V_carp_allow) { 546 m_freem(m); 547 return (IPPROTO_DONE); 548 } 549 550 /* check if received on a valid carp interface */ 551 if (m->m_pkthdr.rcvif->if_carp == NULL) { 552 CARPSTATS_INC(carps_badif); 553 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 554 __func__, m->m_pkthdr.rcvif->if_xname); 555 m_freem(m); 556 return (IPPROTO_DONE); 557 } 558 559 /* verify that the IP TTL is 255 */ 560 if (ip6->ip6_hlim != CARP_DFLTTL) { 561 CARPSTATS_INC(carps_badttl); 562 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 563 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 564 m_freem(m); 565 return (IPPROTO_DONE); 566 } 567 568 /* verify that we have a complete carp packet */ 569 if (m->m_len < *offp + sizeof(*ch)) { 570 len = m->m_len; 571 m = m_pullup(m, *offp + sizeof(*ch)); 572 if (m == NULL) { 573 CARPSTATS_INC(carps_badlen); 574 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 575 return (IPPROTO_DONE); 576 } 577 } 578 ch = (struct carp_header *)(mtod(m, char *) + *offp); 579 580 581 /* verify the CARP checksum */ 582 m->m_data += *offp; 583 if (in_cksum(m, sizeof(*ch))) { 584 CARPSTATS_INC(carps_badsum); 585 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 586 m->m_pkthdr.rcvif->if_xname); 587 m_freem(m); 588 return (IPPROTO_DONE); 589 } 590 m->m_data -= *offp; 591 592 carp_input_c(m, ch, AF_INET6); 593 return (IPPROTO_DONE); 594 } 595 #endif /* INET6 */ 596 597 /* 598 * This routine should not be necessary at all, but some switches 599 * (VMWare ESX vswitches) can echo our own packets back at us, 600 * and we must ignore them or they will cause us to drop out of 601 * MASTER mode. 602 * 603 * We cannot catch all cases of network loops. Instead, what we 604 * do here is catch any packet that arrives with a carp header 605 * with a VHID of 0, that comes from an address that is our own. 606 * These packets are by definition "from us" (even if they are from 607 * a misconfigured host that is pretending to be us). 608 * 609 * The VHID test is outside this mini-function. 610 */ 611 static int 612 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 613 { 614 #ifdef INET 615 struct ip *ip4; 616 struct in_addr in4; 617 #endif 618 #ifdef INET6 619 struct ip6_hdr *ip6; 620 struct in6_addr in6; 621 #endif 622 623 switch (af) { 624 #ifdef INET 625 case AF_INET: 626 ip4 = mtod(m, struct ip *); 627 in4 = ifatoia(ifa)->ia_addr.sin_addr; 628 return (in4.s_addr == ip4->ip_src.s_addr); 629 #endif 630 #ifdef INET6 631 case AF_INET6: 632 ip6 = mtod(m, struct ip6_hdr *); 633 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 634 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 635 #endif 636 default: 637 break; 638 } 639 return (0); 640 } 641 642 static void 643 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 644 { 645 struct ifnet *ifp = m->m_pkthdr.rcvif; 646 struct ifaddr *ifa, *match; 647 struct carp_softc *sc; 648 uint64_t tmp_counter; 649 struct timeval sc_tv, ch_tv; 650 int error; 651 652 NET_EPOCH_ASSERT(); 653 654 /* 655 * Verify that the VHID is valid on the receiving interface. 656 * 657 * There should be just one match. If there are none 658 * the VHID is not valid and we drop the packet. If 659 * there are multiple VHID matches, take just the first 660 * one, for compatibility with previous code. While we're 661 * scanning, check for obvious loops in the network topology 662 * (these should never happen, and as noted above, we may 663 * miss real loops; this is just a double-check). 664 */ 665 error = 0; 666 match = NULL; 667 IFNET_FOREACH_IFA(ifp, ifa) { 668 if (match == NULL && ifa->ifa_carp != NULL && 669 ifa->ifa_addr->sa_family == af && 670 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 671 match = ifa; 672 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 673 error = ELOOP; 674 } 675 ifa = error ? NULL : match; 676 if (ifa != NULL) 677 ifa_ref(ifa); 678 679 if (ifa == NULL) { 680 if (error == ELOOP) { 681 CARP_DEBUG("dropping looped packet on interface %s\n", 682 ifp->if_xname); 683 CARPSTATS_INC(carps_badif); /* ??? */ 684 } else { 685 CARPSTATS_INC(carps_badvhid); 686 } 687 m_freem(m); 688 return; 689 } 690 691 /* verify the CARP version. */ 692 if (ch->carp_version != CARP_VERSION) { 693 CARPSTATS_INC(carps_badver); 694 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 695 ch->carp_version); 696 ifa_free(ifa); 697 m_freem(m); 698 return; 699 } 700 701 sc = ifa->ifa_carp; 702 CARP_LOCK(sc); 703 ifa_free(ifa); 704 705 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 706 CARPSTATS_INC(carps_badauth); 707 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 708 sc->sc_vhid, ifp->if_xname); 709 goto out; 710 } 711 712 tmp_counter = ntohl(ch->carp_counter[0]); 713 tmp_counter = tmp_counter<<32; 714 tmp_counter += ntohl(ch->carp_counter[1]); 715 716 /* XXX Replay protection goes here */ 717 718 sc->sc_init_counter = 0; 719 sc->sc_counter = tmp_counter; 720 721 sc_tv.tv_sec = sc->sc_advbase; 722 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 723 ch_tv.tv_sec = ch->carp_advbase; 724 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 725 726 switch (sc->sc_state) { 727 case INIT: 728 break; 729 case MASTER: 730 /* 731 * If we receive an advertisement from a master who's going to 732 * be more frequent than us, go into BACKUP state. 733 */ 734 if (timevalcmp(&sc_tv, &ch_tv, >) || 735 timevalcmp(&sc_tv, &ch_tv, ==)) { 736 callout_stop(&sc->sc_ad_tmo); 737 carp_set_state(sc, BACKUP, 738 "more frequent advertisement received"); 739 carp_setrun(sc, 0); 740 carp_delroute(sc); 741 } 742 break; 743 case BACKUP: 744 /* 745 * If we're pre-empting masters who advertise slower than us, 746 * and this one claims to be slower, treat him as down. 747 */ 748 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 749 carp_master_down_locked(sc, 750 "preempting a slower master"); 751 break; 752 } 753 754 /* 755 * If the master is going to advertise at such a low frequency 756 * that he's guaranteed to time out, we'd might as well just 757 * treat him as timed out now. 758 */ 759 sc_tv.tv_sec = sc->sc_advbase * 3; 760 if (timevalcmp(&sc_tv, &ch_tv, <)) { 761 carp_master_down_locked(sc, "master will time out"); 762 break; 763 } 764 765 /* 766 * Otherwise, we reset the counter and wait for the next 767 * advertisement. 768 */ 769 carp_setrun(sc, af); 770 break; 771 } 772 773 out: 774 CARP_UNLOCK(sc); 775 m_freem(m); 776 } 777 778 static int 779 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 780 { 781 struct m_tag *mtag; 782 783 if (sc->sc_init_counter) { 784 /* this could also be seconds since unix epoch */ 785 sc->sc_counter = arc4random(); 786 sc->sc_counter = sc->sc_counter << 32; 787 sc->sc_counter += arc4random(); 788 } else 789 sc->sc_counter++; 790 791 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 792 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 793 794 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 795 796 /* Tag packet for carp_output */ 797 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 798 M_NOWAIT)) == NULL) { 799 m_freem(m); 800 CARPSTATS_INC(carps_onomem); 801 return (ENOMEM); 802 } 803 bcopy(&sc, mtag + 1, sizeof(sc)); 804 m_tag_prepend(m, mtag); 805 806 return (0); 807 } 808 809 /* 810 * To avoid LORs and possible recursions this function shouldn't 811 * be called directly, but scheduled via taskqueue. 812 */ 813 static void 814 carp_send_ad_all(void *ctx __unused, int pending __unused) 815 { 816 struct carp_softc *sc; 817 818 mtx_lock(&carp_mtx); 819 LIST_FOREACH(sc, &carp_list, sc_next) 820 if (sc->sc_state == MASTER) { 821 CARP_LOCK(sc); 822 CURVNET_SET(sc->sc_carpdev->if_vnet); 823 carp_send_ad_locked(sc); 824 CURVNET_RESTORE(); 825 CARP_UNLOCK(sc); 826 } 827 mtx_unlock(&carp_mtx); 828 } 829 830 /* Send a periodic advertisement, executed in callout context. */ 831 static void 832 carp_send_ad(void *v) 833 { 834 struct carp_softc *sc = v; 835 836 CARP_LOCK_ASSERT(sc); 837 CURVNET_SET(sc->sc_carpdev->if_vnet); 838 carp_send_ad_locked(sc); 839 CURVNET_RESTORE(); 840 CARP_UNLOCK(sc); 841 } 842 843 static void 844 carp_send_ad_error(struct carp_softc *sc, int error) 845 { 846 847 if (error) { 848 if (sc->sc_sendad_errors < INT_MAX) 849 sc->sc_sendad_errors++; 850 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 851 static const char fmt[] = "send error %d on %s"; 852 char msg[sizeof(fmt) + IFNAMSIZ]; 853 854 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 855 carp_demote_adj(V_carp_senderr_adj, msg); 856 } 857 sc->sc_sendad_success = 0; 858 } else { 859 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && 860 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 861 static const char fmt[] = "send ok on %s"; 862 char msg[sizeof(fmt) + IFNAMSIZ]; 863 864 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 865 carp_demote_adj(-V_carp_senderr_adj, msg); 866 sc->sc_sendad_errors = 0; 867 } else 868 sc->sc_sendad_errors = 0; 869 } 870 } 871 872 /* 873 * Pick the best ifaddr on the given ifp for sending CARP 874 * advertisements. 875 * 876 * "Best" here is defined by ifa_preferred(). This function is much 877 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 878 * 879 * (This could be simplified to return the actual address, except that 880 * it has a different format in AF_INET and AF_INET6.) 881 */ 882 static struct ifaddr * 883 carp_best_ifa(int af, struct ifnet *ifp) 884 { 885 struct ifaddr *ifa, *best; 886 887 NET_EPOCH_ASSERT(); 888 889 if (af >= AF_MAX) 890 return (NULL); 891 best = NULL; 892 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 893 if (ifa->ifa_addr->sa_family == af && 894 (best == NULL || ifa_preferred(best, ifa))) 895 best = ifa; 896 } 897 if (best != NULL) 898 ifa_ref(best); 899 return (best); 900 } 901 902 static void 903 carp_send_ad_locked(struct carp_softc *sc) 904 { 905 struct carp_header ch; 906 struct timeval tv; 907 struct ifaddr *ifa; 908 struct carp_header *ch_ptr; 909 struct mbuf *m; 910 int len, advskew; 911 912 CARP_LOCK_ASSERT(sc); 913 914 advskew = DEMOTE_ADVSKEW(sc); 915 tv.tv_sec = sc->sc_advbase; 916 tv.tv_usec = advskew * 1000000 / 256; 917 918 ch.carp_version = CARP_VERSION; 919 ch.carp_type = CARP_ADVERTISEMENT; 920 ch.carp_vhid = sc->sc_vhid; 921 ch.carp_advbase = sc->sc_advbase; 922 ch.carp_advskew = advskew; 923 ch.carp_authlen = 7; /* XXX DEFINE */ 924 ch.carp_pad1 = 0; /* must be zero */ 925 ch.carp_cksum = 0; 926 927 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 928 929 #ifdef INET 930 if (sc->sc_naddrs) { 931 struct ip *ip; 932 933 m = m_gethdr(M_NOWAIT, MT_DATA); 934 if (m == NULL) { 935 CARPSTATS_INC(carps_onomem); 936 goto resched; 937 } 938 len = sizeof(*ip) + sizeof(ch); 939 m->m_pkthdr.len = len; 940 m->m_pkthdr.rcvif = NULL; 941 m->m_len = len; 942 M_ALIGN(m, m->m_len); 943 m->m_flags |= M_MCAST; 944 ip = mtod(m, struct ip *); 945 ip->ip_v = IPVERSION; 946 ip->ip_hl = sizeof(*ip) >> 2; 947 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET; 948 ip->ip_len = htons(len); 949 ip->ip_off = htons(IP_DF); 950 ip->ip_ttl = CARP_DFLTTL; 951 ip->ip_p = IPPROTO_CARP; 952 ip->ip_sum = 0; 953 ip_fillid(ip); 954 955 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 956 if (ifa != NULL) { 957 ip->ip_src.s_addr = 958 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 959 ifa_free(ifa); 960 } else 961 ip->ip_src.s_addr = 0; 962 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 963 964 ch_ptr = (struct carp_header *)(&ip[1]); 965 bcopy(&ch, ch_ptr, sizeof(ch)); 966 if (carp_prepare_ad(m, sc, ch_ptr)) 967 goto resched; 968 969 m->m_data += sizeof(*ip); 970 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 971 m->m_data -= sizeof(*ip); 972 973 CARPSTATS_INC(carps_opackets); 974 975 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 976 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 977 } 978 #endif /* INET */ 979 #ifdef INET6 980 if (sc->sc_naddrs6) { 981 struct ip6_hdr *ip6; 982 983 m = m_gethdr(M_NOWAIT, MT_DATA); 984 if (m == NULL) { 985 CARPSTATS_INC(carps_onomem); 986 goto resched; 987 } 988 len = sizeof(*ip6) + sizeof(ch); 989 m->m_pkthdr.len = len; 990 m->m_pkthdr.rcvif = NULL; 991 m->m_len = len; 992 M_ALIGN(m, m->m_len); 993 m->m_flags |= M_MCAST; 994 ip6 = mtod(m, struct ip6_hdr *); 995 bzero(ip6, sizeof(*ip6)); 996 ip6->ip6_vfc |= IPV6_VERSION; 997 /* Traffic class isn't defined in ip6 struct instead 998 * it gets offset into flowid field */ 999 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN + 1000 IPTOS_DSCP_OFFSET)); 1001 ip6->ip6_hlim = CARP_DFLTTL; 1002 ip6->ip6_nxt = IPPROTO_CARP; 1003 1004 /* set the source address */ 1005 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 1006 if (ifa != NULL) { 1007 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 1008 sizeof(struct in6_addr)); 1009 ifa_free(ifa); 1010 } else 1011 /* This should never happen with IPv6. */ 1012 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 1013 1014 /* Set the multicast destination. */ 1015 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1016 ip6->ip6_dst.s6_addr8[15] = 0x12; 1017 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1018 m_freem(m); 1019 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1020 goto resched; 1021 } 1022 1023 ch_ptr = (struct carp_header *)(&ip6[1]); 1024 bcopy(&ch, ch_ptr, sizeof(ch)); 1025 if (carp_prepare_ad(m, sc, ch_ptr)) 1026 goto resched; 1027 1028 m->m_data += sizeof(*ip6); 1029 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1030 m->m_data -= sizeof(*ip6); 1031 1032 CARPSTATS_INC(carps_opackets6); 1033 1034 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1035 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1036 } 1037 #endif /* INET6 */ 1038 1039 resched: 1040 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1041 } 1042 1043 static void 1044 carp_addroute(struct carp_softc *sc) 1045 { 1046 struct ifaddr *ifa; 1047 1048 CARP_FOREACH_IFA(sc, ifa) 1049 carp_ifa_addroute(ifa); 1050 } 1051 1052 static void 1053 carp_ifa_addroute(struct ifaddr *ifa) 1054 { 1055 1056 switch (ifa->ifa_addr->sa_family) { 1057 #ifdef INET 1058 case AF_INET: 1059 in_addprefix(ifatoia(ifa), RTF_UP); 1060 ifa_add_loopback_route(ifa, 1061 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1062 break; 1063 #endif 1064 #ifdef INET6 1065 case AF_INET6: 1066 ifa_add_loopback_route(ifa, 1067 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1068 nd6_add_ifa_lle(ifatoia6(ifa)); 1069 break; 1070 #endif 1071 } 1072 } 1073 1074 static void 1075 carp_delroute(struct carp_softc *sc) 1076 { 1077 struct ifaddr *ifa; 1078 1079 CARP_FOREACH_IFA(sc, ifa) 1080 carp_ifa_delroute(ifa); 1081 } 1082 1083 static void 1084 carp_ifa_delroute(struct ifaddr *ifa) 1085 { 1086 1087 switch (ifa->ifa_addr->sa_family) { 1088 #ifdef INET 1089 case AF_INET: 1090 ifa_del_loopback_route(ifa, 1091 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1092 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1093 break; 1094 #endif 1095 #ifdef INET6 1096 case AF_INET6: 1097 ifa_del_loopback_route(ifa, 1098 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1099 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1100 break; 1101 #endif 1102 } 1103 } 1104 1105 int 1106 carp_master(struct ifaddr *ifa) 1107 { 1108 struct carp_softc *sc = ifa->ifa_carp; 1109 1110 return (sc->sc_state == MASTER); 1111 } 1112 1113 #ifdef INET 1114 /* 1115 * Broadcast a gratuitous ARP request containing 1116 * the virtual router MAC address for each IP address 1117 * associated with the virtual router. 1118 */ 1119 static void 1120 carp_send_arp(struct carp_softc *sc) 1121 { 1122 struct ifaddr *ifa; 1123 struct in_addr addr; 1124 1125 CARP_FOREACH_IFA(sc, ifa) { 1126 if (ifa->ifa_addr->sa_family != AF_INET) 1127 continue; 1128 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1129 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1130 } 1131 } 1132 1133 int 1134 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1135 { 1136 struct carp_softc *sc = ifa->ifa_carp; 1137 1138 if (sc->sc_state == MASTER) { 1139 *enaddr = LLADDR(&sc->sc_addr); 1140 return (1); 1141 } 1142 1143 return (0); 1144 } 1145 #endif 1146 1147 #ifdef INET6 1148 static void 1149 carp_send_na(struct carp_softc *sc) 1150 { 1151 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1152 struct ifaddr *ifa; 1153 struct in6_addr *in6; 1154 1155 CARP_FOREACH_IFA(sc, ifa) { 1156 if (ifa->ifa_addr->sa_family != AF_INET6) 1157 continue; 1158 1159 in6 = IFA_IN6(ifa); 1160 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1161 ND_NA_FLAG_OVERRIDE, 1, NULL); 1162 DELAY(1000); /* XXX */ 1163 } 1164 } 1165 1166 /* 1167 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1168 * matches and is not a carp address. Returns NULL otherwise. 1169 */ 1170 struct ifaddr * 1171 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1172 { 1173 struct ifaddr *ifa; 1174 1175 NET_EPOCH_ASSERT(); 1176 1177 ifa = NULL; 1178 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1179 if (ifa->ifa_addr->sa_family != AF_INET6) 1180 continue; 1181 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1182 continue; 1183 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1184 ifa = NULL; 1185 else 1186 ifa_ref(ifa); 1187 break; 1188 } 1189 1190 return (ifa); 1191 } 1192 1193 char * 1194 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1195 { 1196 struct ifaddr *ifa; 1197 1198 NET_EPOCH_ASSERT(); 1199 1200 IFNET_FOREACH_IFA(ifp, ifa) 1201 if (ifa->ifa_addr->sa_family == AF_INET6 && 1202 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1203 struct carp_softc *sc = ifa->ifa_carp; 1204 struct m_tag *mtag; 1205 1206 mtag = m_tag_get(PACKET_TAG_CARP, 1207 sizeof(struct carp_softc *), M_NOWAIT); 1208 if (mtag == NULL) 1209 /* Better a bit than nothing. */ 1210 return (LLADDR(&sc->sc_addr)); 1211 1212 bcopy(&sc, mtag + 1, sizeof(sc)); 1213 m_tag_prepend(m, mtag); 1214 1215 return (LLADDR(&sc->sc_addr)); 1216 } 1217 1218 return (NULL); 1219 } 1220 #endif /* INET6 */ 1221 1222 int 1223 carp_forus(struct ifnet *ifp, u_char *dhost) 1224 { 1225 struct carp_softc *sc; 1226 uint8_t *ena = dhost; 1227 1228 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1229 return (0); 1230 1231 CIF_LOCK(ifp->if_carp); 1232 IFNET_FOREACH_CARP(ifp, sc) { 1233 CARP_LOCK(sc); 1234 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1235 ETHER_ADDR_LEN)) { 1236 CARP_UNLOCK(sc); 1237 CIF_UNLOCK(ifp->if_carp); 1238 return (1); 1239 } 1240 CARP_UNLOCK(sc); 1241 } 1242 CIF_UNLOCK(ifp->if_carp); 1243 1244 return (0); 1245 } 1246 1247 /* Master down timeout event, executed in callout context. */ 1248 static void 1249 carp_master_down(void *v) 1250 { 1251 struct carp_softc *sc = v; 1252 1253 CARP_LOCK_ASSERT(sc); 1254 1255 CURVNET_SET(sc->sc_carpdev->if_vnet); 1256 if (sc->sc_state == BACKUP) { 1257 carp_master_down_locked(sc, "master timed out"); 1258 } 1259 CURVNET_RESTORE(); 1260 1261 CARP_UNLOCK(sc); 1262 } 1263 1264 static void 1265 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1266 { 1267 1268 CARP_LOCK_ASSERT(sc); 1269 1270 switch (sc->sc_state) { 1271 case BACKUP: 1272 carp_set_state(sc, MASTER, reason); 1273 carp_send_ad_locked(sc); 1274 #ifdef INET 1275 carp_send_arp(sc); 1276 #endif 1277 #ifdef INET6 1278 carp_send_na(sc); 1279 #endif 1280 carp_setrun(sc, 0); 1281 carp_addroute(sc); 1282 break; 1283 case INIT: 1284 case MASTER: 1285 #ifdef INVARIANTS 1286 panic("carp: VHID %u@%s: master_down event in %s state\n", 1287 sc->sc_vhid, 1288 sc->sc_carpdev->if_xname, 1289 sc->sc_state ? "MASTER" : "INIT"); 1290 #endif 1291 break; 1292 } 1293 } 1294 1295 /* 1296 * When in backup state, af indicates whether to reset the master down timer 1297 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1298 */ 1299 static void 1300 carp_setrun(struct carp_softc *sc, sa_family_t af) 1301 { 1302 struct timeval tv; 1303 1304 CARP_LOCK_ASSERT(sc); 1305 1306 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1307 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1308 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1309 !V_carp_allow) 1310 return; 1311 1312 switch (sc->sc_state) { 1313 case INIT: 1314 carp_set_state(sc, BACKUP, "initialization complete"); 1315 carp_setrun(sc, 0); 1316 break; 1317 case BACKUP: 1318 callout_stop(&sc->sc_ad_tmo); 1319 tv.tv_sec = 3 * sc->sc_advbase; 1320 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1321 switch (af) { 1322 #ifdef INET 1323 case AF_INET: 1324 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1325 carp_master_down, sc); 1326 break; 1327 #endif 1328 #ifdef INET6 1329 case AF_INET6: 1330 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1331 carp_master_down, sc); 1332 break; 1333 #endif 1334 default: 1335 #ifdef INET 1336 if (sc->sc_naddrs) 1337 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1338 carp_master_down, sc); 1339 #endif 1340 #ifdef INET6 1341 if (sc->sc_naddrs6) 1342 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1343 carp_master_down, sc); 1344 #endif 1345 break; 1346 } 1347 break; 1348 case MASTER: 1349 tv.tv_sec = sc->sc_advbase; 1350 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1351 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1352 carp_send_ad, sc); 1353 break; 1354 } 1355 } 1356 1357 /* 1358 * Setup multicast structures. 1359 */ 1360 static int 1361 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1362 { 1363 struct ifnet *ifp = cif->cif_ifp; 1364 int error = 0; 1365 1366 switch (sa) { 1367 #ifdef INET 1368 case AF_INET: 1369 { 1370 struct ip_moptions *imo = &cif->cif_imo; 1371 struct in_mfilter *imf; 1372 struct in_addr addr; 1373 1374 if (ip_mfilter_first(&imo->imo_head) != NULL) 1375 return (0); 1376 1377 imf = ip_mfilter_alloc(M_WAITOK, 0, 0); 1378 ip_mfilter_init(&imo->imo_head); 1379 imo->imo_multicast_vif = -1; 1380 1381 addr.s_addr = htonl(INADDR_CARP_GROUP); 1382 if ((error = in_joingroup(ifp, &addr, NULL, 1383 &imf->imf_inm)) != 0) { 1384 ip_mfilter_free(imf); 1385 break; 1386 } 1387 1388 ip_mfilter_insert(&imo->imo_head, imf); 1389 imo->imo_multicast_ifp = ifp; 1390 imo->imo_multicast_ttl = CARP_DFLTTL; 1391 imo->imo_multicast_loop = 0; 1392 break; 1393 } 1394 #endif 1395 #ifdef INET6 1396 case AF_INET6: 1397 { 1398 struct ip6_moptions *im6o = &cif->cif_im6o; 1399 struct in6_mfilter *im6f[2]; 1400 struct in6_addr in6; 1401 1402 if (ip6_mfilter_first(&im6o->im6o_head)) 1403 return (0); 1404 1405 im6f[0] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1406 im6f[1] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1407 1408 ip6_mfilter_init(&im6o->im6o_head); 1409 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1410 im6o->im6o_multicast_ifp = ifp; 1411 1412 /* Join IPv6 CARP multicast group. */ 1413 bzero(&in6, sizeof(in6)); 1414 in6.s6_addr16[0] = htons(0xff02); 1415 in6.s6_addr8[15] = 0x12; 1416 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1417 ip6_mfilter_free(im6f[0]); 1418 ip6_mfilter_free(im6f[1]); 1419 break; 1420 } 1421 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[0]->im6f_in6m, 0)) != 0) { 1422 ip6_mfilter_free(im6f[0]); 1423 ip6_mfilter_free(im6f[1]); 1424 break; 1425 } 1426 1427 /* Join solicited multicast address. */ 1428 bzero(&in6, sizeof(in6)); 1429 in6.s6_addr16[0] = htons(0xff02); 1430 in6.s6_addr32[1] = 0; 1431 in6.s6_addr32[2] = htonl(1); 1432 in6.s6_addr32[3] = 0; 1433 in6.s6_addr8[12] = 0xff; 1434 1435 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1436 ip6_mfilter_free(im6f[0]); 1437 ip6_mfilter_free(im6f[1]); 1438 break; 1439 } 1440 1441 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[1]->im6f_in6m, 0)) != 0) { 1442 in6_leavegroup(im6f[0]->im6f_in6m, NULL); 1443 ip6_mfilter_free(im6f[0]); 1444 ip6_mfilter_free(im6f[1]); 1445 break; 1446 } 1447 ip6_mfilter_insert(&im6o->im6o_head, im6f[0]); 1448 ip6_mfilter_insert(&im6o->im6o_head, im6f[1]); 1449 break; 1450 } 1451 #endif 1452 } 1453 1454 return (error); 1455 } 1456 1457 /* 1458 * Free multicast structures. 1459 */ 1460 static void 1461 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1462 { 1463 #ifdef INET 1464 struct ip_moptions *imo = &cif->cif_imo; 1465 struct in_mfilter *imf; 1466 #endif 1467 #ifdef INET6 1468 struct ip6_moptions *im6o = &cif->cif_im6o; 1469 struct in6_mfilter *im6f; 1470 #endif 1471 sx_assert(&carp_sx, SA_XLOCKED); 1472 1473 switch (sa) { 1474 #ifdef INET 1475 case AF_INET: 1476 if (cif->cif_naddrs != 0) 1477 break; 1478 1479 while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) { 1480 ip_mfilter_remove(&imo->imo_head, imf); 1481 in_leavegroup(imf->imf_inm, NULL); 1482 ip_mfilter_free(imf); 1483 } 1484 break; 1485 #endif 1486 #ifdef INET6 1487 case AF_INET6: 1488 if (cif->cif_naddrs6 != 0) 1489 break; 1490 1491 while ((im6f = ip6_mfilter_first(&im6o->im6o_head)) != NULL) { 1492 ip6_mfilter_remove(&im6o->im6o_head, im6f); 1493 in6_leavegroup(im6f->im6f_in6m, NULL); 1494 ip6_mfilter_free(im6f); 1495 } 1496 break; 1497 #endif 1498 } 1499 } 1500 1501 int 1502 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1503 { 1504 struct m_tag *mtag; 1505 struct carp_softc *sc; 1506 1507 if (!sa) 1508 return (0); 1509 1510 switch (sa->sa_family) { 1511 #ifdef INET 1512 case AF_INET: 1513 break; 1514 #endif 1515 #ifdef INET6 1516 case AF_INET6: 1517 break; 1518 #endif 1519 default: 1520 return (0); 1521 } 1522 1523 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1524 if (mtag == NULL) 1525 return (0); 1526 1527 bcopy(mtag + 1, &sc, sizeof(sc)); 1528 1529 /* Set the source MAC address to the Virtual Router MAC Address. */ 1530 switch (ifp->if_type) { 1531 case IFT_ETHER: 1532 case IFT_BRIDGE: 1533 case IFT_L2VLAN: { 1534 struct ether_header *eh; 1535 1536 eh = mtod(m, struct ether_header *); 1537 eh->ether_shost[0] = 0; 1538 eh->ether_shost[1] = 0; 1539 eh->ether_shost[2] = 0x5e; 1540 eh->ether_shost[3] = 0; 1541 eh->ether_shost[4] = 1; 1542 eh->ether_shost[5] = sc->sc_vhid; 1543 } 1544 break; 1545 default: 1546 printf("%s: carp is not supported for the %d interface type\n", 1547 ifp->if_xname, ifp->if_type); 1548 return (EOPNOTSUPP); 1549 } 1550 1551 return (0); 1552 } 1553 1554 static struct carp_softc* 1555 carp_alloc(struct ifnet *ifp) 1556 { 1557 struct carp_softc *sc; 1558 struct carp_if *cif; 1559 1560 sx_assert(&carp_sx, SA_XLOCKED); 1561 1562 if ((cif = ifp->if_carp) == NULL) 1563 cif = carp_alloc_if(ifp); 1564 1565 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1566 1567 sc->sc_advbase = CARP_DFLTINTV; 1568 sc->sc_vhid = -1; /* required setting */ 1569 sc->sc_init_counter = 1; 1570 sc->sc_state = INIT; 1571 1572 sc->sc_ifasiz = sizeof(struct ifaddr *); 1573 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1574 sc->sc_carpdev = ifp; 1575 1576 CARP_LOCK_INIT(sc); 1577 #ifdef INET 1578 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1579 #endif 1580 #ifdef INET6 1581 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1582 #endif 1583 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1584 1585 CIF_LOCK(cif); 1586 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1587 CIF_UNLOCK(cif); 1588 1589 mtx_lock(&carp_mtx); 1590 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1591 mtx_unlock(&carp_mtx); 1592 1593 return (sc); 1594 } 1595 1596 static void 1597 carp_grow_ifas(struct carp_softc *sc) 1598 { 1599 struct ifaddr **new; 1600 1601 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1602 CARP_LOCK(sc); 1603 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1604 free(sc->sc_ifas, M_CARP); 1605 sc->sc_ifas = new; 1606 sc->sc_ifasiz *= 2; 1607 CARP_UNLOCK(sc); 1608 } 1609 1610 static void 1611 carp_destroy(struct carp_softc *sc) 1612 { 1613 struct ifnet *ifp = sc->sc_carpdev; 1614 struct carp_if *cif = ifp->if_carp; 1615 1616 sx_assert(&carp_sx, SA_XLOCKED); 1617 1618 if (sc->sc_suppress) 1619 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1620 CARP_UNLOCK(sc); 1621 1622 CIF_LOCK(cif); 1623 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1624 CIF_UNLOCK(cif); 1625 1626 mtx_lock(&carp_mtx); 1627 LIST_REMOVE(sc, sc_next); 1628 mtx_unlock(&carp_mtx); 1629 1630 callout_drain(&sc->sc_ad_tmo); 1631 #ifdef INET 1632 callout_drain(&sc->sc_md_tmo); 1633 #endif 1634 #ifdef INET6 1635 callout_drain(&sc->sc_md6_tmo); 1636 #endif 1637 CARP_LOCK_DESTROY(sc); 1638 1639 free(sc->sc_ifas, M_CARP); 1640 free(sc, M_CARP); 1641 } 1642 1643 static struct carp_if* 1644 carp_alloc_if(struct ifnet *ifp) 1645 { 1646 struct carp_if *cif; 1647 int error; 1648 1649 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1650 1651 if ((error = ifpromisc(ifp, 1)) != 0) 1652 printf("%s: ifpromisc(%s) failed: %d\n", 1653 __func__, ifp->if_xname, error); 1654 else 1655 cif->cif_flags |= CIF_PROMISC; 1656 1657 CIF_LOCK_INIT(cif); 1658 cif->cif_ifp = ifp; 1659 TAILQ_INIT(&cif->cif_vrs); 1660 1661 IF_ADDR_WLOCK(ifp); 1662 ifp->if_carp = cif; 1663 if_ref(ifp); 1664 IF_ADDR_WUNLOCK(ifp); 1665 1666 return (cif); 1667 } 1668 1669 static void 1670 carp_free_if(struct carp_if *cif) 1671 { 1672 struct ifnet *ifp = cif->cif_ifp; 1673 1674 CIF_LOCK_ASSERT(cif); 1675 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1676 __func__)); 1677 1678 IF_ADDR_WLOCK(ifp); 1679 ifp->if_carp = NULL; 1680 IF_ADDR_WUNLOCK(ifp); 1681 1682 CIF_LOCK_DESTROY(cif); 1683 1684 if (cif->cif_flags & CIF_PROMISC) 1685 ifpromisc(ifp, 0); 1686 if_rele(ifp); 1687 1688 free(cif, M_CARP); 1689 } 1690 1691 static void 1692 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1693 { 1694 1695 CARP_LOCK(sc); 1696 carpr->carpr_state = sc->sc_state; 1697 carpr->carpr_vhid = sc->sc_vhid; 1698 carpr->carpr_advbase = sc->sc_advbase; 1699 carpr->carpr_advskew = sc->sc_advskew; 1700 if (priv) 1701 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1702 else 1703 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1704 CARP_UNLOCK(sc); 1705 } 1706 1707 int 1708 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1709 { 1710 struct carpreq carpr; 1711 struct ifnet *ifp; 1712 struct carp_softc *sc = NULL; 1713 int error = 0, locked = 0; 1714 1715 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1716 return (error); 1717 1718 ifp = ifunit_ref(ifr->ifr_name); 1719 if (ifp == NULL) 1720 return (ENXIO); 1721 1722 switch (ifp->if_type) { 1723 case IFT_ETHER: 1724 case IFT_L2VLAN: 1725 case IFT_BRIDGE: 1726 break; 1727 default: 1728 error = EOPNOTSUPP; 1729 goto out; 1730 } 1731 1732 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1733 error = EADDRNOTAVAIL; 1734 goto out; 1735 } 1736 1737 sx_xlock(&carp_sx); 1738 switch (cmd) { 1739 case SIOCSVH: 1740 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1741 break; 1742 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1743 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1744 error = EINVAL; 1745 break; 1746 } 1747 1748 if (ifp->if_carp) { 1749 IFNET_FOREACH_CARP(ifp, sc) 1750 if (sc->sc_vhid == carpr.carpr_vhid) 1751 break; 1752 } 1753 if (sc == NULL) { 1754 sc = carp_alloc(ifp); 1755 CARP_LOCK(sc); 1756 sc->sc_vhid = carpr.carpr_vhid; 1757 LLADDR(&sc->sc_addr)[0] = 0; 1758 LLADDR(&sc->sc_addr)[1] = 0; 1759 LLADDR(&sc->sc_addr)[2] = 0x5e; 1760 LLADDR(&sc->sc_addr)[3] = 0; 1761 LLADDR(&sc->sc_addr)[4] = 1; 1762 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1763 } else 1764 CARP_LOCK(sc); 1765 locked = 1; 1766 if (carpr.carpr_advbase > 0) { 1767 if (carpr.carpr_advbase > 255 || 1768 carpr.carpr_advbase < CARP_DFLTINTV) { 1769 error = EINVAL; 1770 break; 1771 } 1772 sc->sc_advbase = carpr.carpr_advbase; 1773 } 1774 if (carpr.carpr_advskew >= 255) { 1775 error = EINVAL; 1776 break; 1777 } 1778 sc->sc_advskew = carpr.carpr_advskew; 1779 if (carpr.carpr_key[0] != '\0') { 1780 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1781 carp_hmac_prepare(sc); 1782 } 1783 if (sc->sc_state != INIT && 1784 carpr.carpr_state != sc->sc_state) { 1785 switch (carpr.carpr_state) { 1786 case BACKUP: 1787 callout_stop(&sc->sc_ad_tmo); 1788 carp_set_state(sc, BACKUP, 1789 "user requested via ifconfig"); 1790 carp_setrun(sc, 0); 1791 carp_delroute(sc); 1792 break; 1793 case MASTER: 1794 carp_master_down_locked(sc, 1795 "user requested via ifconfig"); 1796 break; 1797 default: 1798 break; 1799 } 1800 } 1801 break; 1802 1803 case SIOCGVH: 1804 { 1805 int priveleged; 1806 1807 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1808 error = EINVAL; 1809 break; 1810 } 1811 if (carpr.carpr_count < 1) { 1812 error = EMSGSIZE; 1813 break; 1814 } 1815 if (ifp->if_carp == NULL) { 1816 error = ENOENT; 1817 break; 1818 } 1819 1820 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1821 if (carpr.carpr_vhid != 0) { 1822 IFNET_FOREACH_CARP(ifp, sc) 1823 if (sc->sc_vhid == carpr.carpr_vhid) 1824 break; 1825 if (sc == NULL) { 1826 error = ENOENT; 1827 break; 1828 } 1829 carp_carprcp(&carpr, sc, priveleged); 1830 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1831 sizeof(carpr)); 1832 } else { 1833 int i, count; 1834 1835 count = 0; 1836 IFNET_FOREACH_CARP(ifp, sc) 1837 count++; 1838 1839 if (count > carpr.carpr_count) { 1840 CIF_UNLOCK(ifp->if_carp); 1841 error = EMSGSIZE; 1842 break; 1843 } 1844 1845 i = 0; 1846 IFNET_FOREACH_CARP(ifp, sc) { 1847 carp_carprcp(&carpr, sc, priveleged); 1848 carpr.carpr_count = count; 1849 error = copyout(&carpr, 1850 (char *)ifr_data_get_ptr(ifr) + 1851 (i * sizeof(carpr)), sizeof(carpr)); 1852 if (error) { 1853 CIF_UNLOCK(ifp->if_carp); 1854 break; 1855 } 1856 i++; 1857 } 1858 } 1859 break; 1860 } 1861 default: 1862 error = EINVAL; 1863 } 1864 sx_xunlock(&carp_sx); 1865 1866 out: 1867 if (locked) 1868 CARP_UNLOCK(sc); 1869 if_rele(ifp); 1870 1871 return (error); 1872 } 1873 1874 static int 1875 carp_get_vhid(struct ifaddr *ifa) 1876 { 1877 1878 if (ifa == NULL || ifa->ifa_carp == NULL) 1879 return (0); 1880 1881 return (ifa->ifa_carp->sc_vhid); 1882 } 1883 1884 int 1885 carp_attach(struct ifaddr *ifa, int vhid) 1886 { 1887 struct ifnet *ifp = ifa->ifa_ifp; 1888 struct carp_if *cif = ifp->if_carp; 1889 struct carp_softc *sc; 1890 int index, error; 1891 1892 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1893 1894 switch (ifa->ifa_addr->sa_family) { 1895 #ifdef INET 1896 case AF_INET: 1897 #endif 1898 #ifdef INET6 1899 case AF_INET6: 1900 #endif 1901 break; 1902 default: 1903 return (EPROTOTYPE); 1904 } 1905 1906 sx_xlock(&carp_sx); 1907 if (ifp->if_carp == NULL) { 1908 sx_xunlock(&carp_sx); 1909 return (ENOPROTOOPT); 1910 } 1911 1912 IFNET_FOREACH_CARP(ifp, sc) 1913 if (sc->sc_vhid == vhid) 1914 break; 1915 if (sc == NULL) { 1916 sx_xunlock(&carp_sx); 1917 return (ENOENT); 1918 } 1919 1920 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1921 if (error) { 1922 CIF_FREE(cif); 1923 sx_xunlock(&carp_sx); 1924 return (error); 1925 } 1926 1927 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1928 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1929 carp_grow_ifas(sc); 1930 1931 switch (ifa->ifa_addr->sa_family) { 1932 #ifdef INET 1933 case AF_INET: 1934 cif->cif_naddrs++; 1935 sc->sc_naddrs++; 1936 break; 1937 #endif 1938 #ifdef INET6 1939 case AF_INET6: 1940 cif->cif_naddrs6++; 1941 sc->sc_naddrs6++; 1942 break; 1943 #endif 1944 } 1945 1946 ifa_ref(ifa); 1947 1948 CARP_LOCK(sc); 1949 sc->sc_ifas[index - 1] = ifa; 1950 ifa->ifa_carp = sc; 1951 carp_hmac_prepare(sc); 1952 carp_sc_state(sc); 1953 CARP_UNLOCK(sc); 1954 1955 sx_xunlock(&carp_sx); 1956 1957 return (0); 1958 } 1959 1960 void 1961 carp_detach(struct ifaddr *ifa, bool keep_cif) 1962 { 1963 struct ifnet *ifp = ifa->ifa_ifp; 1964 struct carp_if *cif = ifp->if_carp; 1965 struct carp_softc *sc = ifa->ifa_carp; 1966 int i, index; 1967 1968 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1969 1970 sx_xlock(&carp_sx); 1971 1972 CARP_LOCK(sc); 1973 /* Shift array. */ 1974 index = sc->sc_naddrs + sc->sc_naddrs6; 1975 for (i = 0; i < index; i++) 1976 if (sc->sc_ifas[i] == ifa) 1977 break; 1978 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1979 for (; i < index - 1; i++) 1980 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 1981 sc->sc_ifas[index - 1] = NULL; 1982 1983 switch (ifa->ifa_addr->sa_family) { 1984 #ifdef INET 1985 case AF_INET: 1986 cif->cif_naddrs--; 1987 sc->sc_naddrs--; 1988 break; 1989 #endif 1990 #ifdef INET6 1991 case AF_INET6: 1992 cif->cif_naddrs6--; 1993 sc->sc_naddrs6--; 1994 break; 1995 #endif 1996 } 1997 1998 carp_ifa_delroute(ifa); 1999 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 2000 2001 ifa->ifa_carp = NULL; 2002 ifa_free(ifa); 2003 2004 carp_hmac_prepare(sc); 2005 carp_sc_state(sc); 2006 2007 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2008 carp_destroy(sc); 2009 else 2010 CARP_UNLOCK(sc); 2011 2012 if (!keep_cif) 2013 CIF_FREE(cif); 2014 2015 sx_xunlock(&carp_sx); 2016 } 2017 2018 static void 2019 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2020 { 2021 2022 CARP_LOCK_ASSERT(sc); 2023 2024 if (sc->sc_state != state) { 2025 const char *carp_states[] = { CARP_STATES }; 2026 char subsys[IFNAMSIZ+5]; 2027 2028 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2029 sc->sc_carpdev->if_xname); 2030 2031 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2032 carp_states[sc->sc_state], carp_states[state], reason); 2033 2034 sc->sc_state = state; 2035 2036 devctl_notify("CARP", subsys, carp_states[state], NULL); 2037 } 2038 } 2039 2040 static void 2041 carp_linkstate(struct ifnet *ifp) 2042 { 2043 struct carp_softc *sc; 2044 2045 CIF_LOCK(ifp->if_carp); 2046 IFNET_FOREACH_CARP(ifp, sc) { 2047 CARP_LOCK(sc); 2048 carp_sc_state(sc); 2049 CARP_UNLOCK(sc); 2050 } 2051 CIF_UNLOCK(ifp->if_carp); 2052 } 2053 2054 static void 2055 carp_sc_state(struct carp_softc *sc) 2056 { 2057 2058 CARP_LOCK_ASSERT(sc); 2059 2060 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2061 !(sc->sc_carpdev->if_flags & IFF_UP) || 2062 !V_carp_allow) { 2063 callout_stop(&sc->sc_ad_tmo); 2064 #ifdef INET 2065 callout_stop(&sc->sc_md_tmo); 2066 #endif 2067 #ifdef INET6 2068 callout_stop(&sc->sc_md6_tmo); 2069 #endif 2070 carp_set_state(sc, INIT, "hardware interface down"); 2071 carp_setrun(sc, 0); 2072 if (!sc->sc_suppress) 2073 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2074 sc->sc_suppress = 1; 2075 } else { 2076 carp_set_state(sc, INIT, "hardware interface up"); 2077 carp_setrun(sc, 0); 2078 if (sc->sc_suppress) 2079 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2080 sc->sc_suppress = 0; 2081 } 2082 } 2083 2084 static void 2085 carp_demote_adj(int adj, char *reason) 2086 { 2087 atomic_add_int(&V_carp_demotion, adj); 2088 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2089 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2090 } 2091 2092 static int 2093 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2094 { 2095 int new, error; 2096 struct carp_softc *sc; 2097 2098 new = V_carp_allow; 2099 error = sysctl_handle_int(oidp, &new, 0, req); 2100 if (error || !req->newptr) 2101 return (error); 2102 2103 if (V_carp_allow != new) { 2104 V_carp_allow = new; 2105 2106 mtx_lock(&carp_mtx); 2107 LIST_FOREACH(sc, &carp_list, sc_next) { 2108 CARP_LOCK(sc); 2109 if (curvnet == sc->sc_carpdev->if_vnet) 2110 carp_sc_state(sc); 2111 CARP_UNLOCK(sc); 2112 } 2113 mtx_unlock(&carp_mtx); 2114 } 2115 2116 return (0); 2117 } 2118 2119 static int 2120 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS) 2121 { 2122 int new, error; 2123 2124 new = V_carp_dscp; 2125 error = sysctl_handle_int(oidp, &new, 0, req); 2126 if (error || !req->newptr) 2127 return (error); 2128 2129 if (new < 0 || new > 63) 2130 return (EINVAL); 2131 2132 V_carp_dscp = new; 2133 2134 return (0); 2135 } 2136 2137 static int 2138 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2139 { 2140 int new, error; 2141 2142 new = V_carp_demotion; 2143 error = sysctl_handle_int(oidp, &new, 0, req); 2144 if (error || !req->newptr) 2145 return (error); 2146 2147 carp_demote_adj(new, "sysctl"); 2148 2149 return (0); 2150 } 2151 2152 #ifdef INET 2153 extern struct domain inetdomain; 2154 static struct protosw in_carp_protosw = { 2155 .pr_type = SOCK_RAW, 2156 .pr_domain = &inetdomain, 2157 .pr_protocol = IPPROTO_CARP, 2158 .pr_flags = PR_ATOMIC|PR_ADDR, 2159 .pr_input = carp_input, 2160 .pr_output = rip_output, 2161 .pr_ctloutput = rip_ctloutput, 2162 .pr_usrreqs = &rip_usrreqs 2163 }; 2164 #endif 2165 2166 #ifdef INET6 2167 extern struct domain inet6domain; 2168 static struct protosw in6_carp_protosw = { 2169 .pr_type = SOCK_RAW, 2170 .pr_domain = &inet6domain, 2171 .pr_protocol = IPPROTO_CARP, 2172 .pr_flags = PR_ATOMIC|PR_ADDR, 2173 .pr_input = carp6_input, 2174 .pr_output = rip6_output, 2175 .pr_ctloutput = rip6_ctloutput, 2176 .pr_usrreqs = &rip6_usrreqs 2177 }; 2178 #endif 2179 2180 static void 2181 carp_mod_cleanup(void) 2182 { 2183 2184 #ifdef INET 2185 if (proto_reg[CARP_INET] == 0) { 2186 (void)ipproto_unregister(IPPROTO_CARP); 2187 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2188 proto_reg[CARP_INET] = -1; 2189 } 2190 carp_iamatch_p = NULL; 2191 #endif 2192 #ifdef INET6 2193 if (proto_reg[CARP_INET6] == 0) { 2194 (void)ip6proto_unregister(IPPROTO_CARP); 2195 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2196 proto_reg[CARP_INET6] = -1; 2197 } 2198 carp_iamatch6_p = NULL; 2199 carp_macmatch6_p = NULL; 2200 #endif 2201 carp_ioctl_p = NULL; 2202 carp_attach_p = NULL; 2203 carp_detach_p = NULL; 2204 carp_get_vhid_p = NULL; 2205 carp_linkstate_p = NULL; 2206 carp_forus_p = NULL; 2207 carp_output_p = NULL; 2208 carp_demote_adj_p = NULL; 2209 carp_master_p = NULL; 2210 mtx_unlock(&carp_mtx); 2211 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2212 mtx_destroy(&carp_mtx); 2213 sx_destroy(&carp_sx); 2214 } 2215 2216 static int 2217 carp_mod_load(void) 2218 { 2219 int err; 2220 2221 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2222 sx_init(&carp_sx, "carp_sx"); 2223 LIST_INIT(&carp_list); 2224 carp_get_vhid_p = carp_get_vhid; 2225 carp_forus_p = carp_forus; 2226 carp_output_p = carp_output; 2227 carp_linkstate_p = carp_linkstate; 2228 carp_ioctl_p = carp_ioctl; 2229 carp_attach_p = carp_attach; 2230 carp_detach_p = carp_detach; 2231 carp_demote_adj_p = carp_demote_adj; 2232 carp_master_p = carp_master; 2233 #ifdef INET6 2234 carp_iamatch6_p = carp_iamatch6; 2235 carp_macmatch6_p = carp_macmatch6; 2236 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2237 (struct protosw *)&in6_carp_protosw); 2238 if (proto_reg[CARP_INET6]) { 2239 printf("carp: error %d attaching to PF_INET6\n", 2240 proto_reg[CARP_INET6]); 2241 carp_mod_cleanup(); 2242 return (proto_reg[CARP_INET6]); 2243 } 2244 err = ip6proto_register(IPPROTO_CARP); 2245 if (err) { 2246 printf("carp: error %d registering with INET6\n", err); 2247 carp_mod_cleanup(); 2248 return (err); 2249 } 2250 #endif 2251 #ifdef INET 2252 carp_iamatch_p = carp_iamatch; 2253 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2254 if (proto_reg[CARP_INET]) { 2255 printf("carp: error %d attaching to PF_INET\n", 2256 proto_reg[CARP_INET]); 2257 carp_mod_cleanup(); 2258 return (proto_reg[CARP_INET]); 2259 } 2260 err = ipproto_register(IPPROTO_CARP); 2261 if (err) { 2262 printf("carp: error %d registering with INET\n", err); 2263 carp_mod_cleanup(); 2264 return (err); 2265 } 2266 #endif 2267 return (0); 2268 } 2269 2270 static int 2271 carp_modevent(module_t mod, int type, void *data) 2272 { 2273 switch (type) { 2274 case MOD_LOAD: 2275 return carp_mod_load(); 2276 /* NOTREACHED */ 2277 case MOD_UNLOAD: 2278 mtx_lock(&carp_mtx); 2279 if (LIST_EMPTY(&carp_list)) 2280 carp_mod_cleanup(); 2281 else { 2282 mtx_unlock(&carp_mtx); 2283 return (EBUSY); 2284 } 2285 break; 2286 2287 default: 2288 return (EINVAL); 2289 } 2290 2291 return (0); 2292 } 2293 2294 static moduledata_t carp_mod = { 2295 "carp", 2296 carp_modevent, 2297 0 2298 }; 2299 2300 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2301