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/devctl.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/socket.h> 50 #include <sys/sockio.h> 51 #include <sys/sysctl.h> 52 #include <sys/syslog.h> 53 #include <sys/taskqueue.h> 54 #include <sys/counter.h> 55 56 #include <net/ethernet.h> 57 #include <net/if.h> 58 #include <net/if_var.h> 59 #include <net/if_dl.h> 60 #include <net/if_llatbl.h> 61 #include <net/if_types.h> 62 #include <net/route.h> 63 #include <net/vnet.h> 64 65 #if defined(INET) || defined(INET6) 66 #include <netinet/in.h> 67 #include <netinet/in_var.h> 68 #include <netinet/ip_carp.h> 69 #include <netinet/ip.h> 70 #include <machine/in_cksum.h> 71 #endif 72 #ifdef INET 73 #include <netinet/ip_var.h> 74 #include <netinet/if_ether.h> 75 #endif 76 77 #ifdef INET6 78 #include <netinet/icmp6.h> 79 #include <netinet/ip6.h> 80 #include <netinet6/in6_var.h> 81 #include <netinet6/ip6_var.h> 82 #include <netinet6/scope6_var.h> 83 #include <netinet6/nd6.h> 84 #endif 85 86 #include <crypto/sha1.h> 87 88 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses"); 89 90 struct carp_softc { 91 struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */ 92 struct ifaddr **sc_ifas; /* Our ifaddrs. */ 93 struct sockaddr_dl sc_addr; /* Our link level address. */ 94 struct callout sc_ad_tmo; /* Advertising timeout. */ 95 #ifdef INET 96 struct callout sc_md_tmo; /* Master down timeout. */ 97 #endif 98 #ifdef INET6 99 struct callout sc_md6_tmo; /* XXX: Master down timeout. */ 100 #endif 101 struct mtx sc_mtx; 102 103 int sc_vhid; 104 int sc_advskew; 105 int sc_advbase; 106 107 int sc_naddrs; 108 int sc_naddrs6; 109 int sc_ifasiz; 110 enum { INIT = 0, BACKUP, MASTER } sc_state; 111 int sc_suppress; 112 int sc_sendad_errors; 113 #define CARP_SENDAD_MAX_ERRORS 3 114 int sc_sendad_success; 115 #define CARP_SENDAD_MIN_SUCCESS 3 116 117 int sc_init_counter; 118 uint64_t sc_counter; 119 120 /* authentication */ 121 #define CARP_HMAC_PAD 64 122 unsigned char sc_key[CARP_KEY_LEN]; 123 unsigned char sc_pad[CARP_HMAC_PAD]; 124 SHA1_CTX sc_sha1; 125 126 TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */ 127 LIST_ENTRY(carp_softc) sc_next; /* On the global list. */ 128 }; 129 130 struct carp_if { 131 #ifdef INET 132 int cif_naddrs; 133 #endif 134 #ifdef INET6 135 int cif_naddrs6; 136 #endif 137 TAILQ_HEAD(, carp_softc) cif_vrs; 138 #ifdef INET 139 struct ip_moptions cif_imo; 140 #endif 141 #ifdef INET6 142 struct ip6_moptions cif_im6o; 143 #endif 144 struct ifnet *cif_ifp; 145 struct mtx cif_mtx; 146 uint32_t cif_flags; 147 #define CIF_PROMISC 0x00000001 148 }; 149 150 /* 151 * Brief design of carp(4). 152 * 153 * Any carp-capable ifnet may have a list of carp softcs hanging off 154 * its ifp->if_carp pointer. Each softc represents one unique virtual 155 * host id, or vhid. The softc has a back pointer to the ifnet. All 156 * softcs are joined in a global list, which has quite limited use. 157 * 158 * Any interface address that takes part in CARP negotiation has a 159 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either 160 * AF_INET or AF_INET6 address. 161 * 162 * Although, one can get the softc's backpointer to ifnet and traverse 163 * through its ifp->if_addrhead queue to find all interface addresses 164 * involved in CARP, we keep a growable array of ifaddr pointers. This 165 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that 166 * do calls into the network stack, thus avoiding LORs. 167 * 168 * Locking: 169 * 170 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), 171 * callout-driven events and ioctl()s. 172 * 173 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. 174 * To traverse the global list we use the mutex carp_mtx. 175 * 176 * Known issues with locking: 177 * 178 * - Sending ad, we put the pointer to the softc in an mtag, and no reference 179 * counting is done on the softc. 180 * - On module unload we may race (?) with packet processing thread 181 * dereferencing our function pointers. 182 */ 183 184 /* Accept incoming CARP packets. */ 185 VNET_DEFINE_STATIC(int, carp_allow) = 1; 186 #define V_carp_allow VNET(carp_allow) 187 188 /* Set DSCP in outgoing CARP packets. */ 189 VNET_DEFINE_STATIC(int, carp_dscp) = 56; 190 #define V_carp_dscp VNET(carp_dscp) 191 192 /* Preempt slower nodes. */ 193 VNET_DEFINE_STATIC(int, carp_preempt) = 0; 194 #define V_carp_preempt VNET(carp_preempt) 195 196 /* Log level. */ 197 VNET_DEFINE_STATIC(int, carp_log) = 1; 198 #define V_carp_log VNET(carp_log) 199 200 /* Global advskew demotion. */ 201 VNET_DEFINE_STATIC(int, carp_demotion) = 0; 202 #define V_carp_demotion VNET(carp_demotion) 203 204 /* Send error demotion factor. */ 205 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW; 206 #define V_carp_senderr_adj VNET(carp_senderr_adj) 207 208 /* Iface down demotion factor. */ 209 VNET_DEFINE_STATIC(int, carp_ifdown_adj) = CARP_MAXSKEW; 210 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 211 212 static int carp_allow_sysctl(SYSCTL_HANDLER_ARGS); 213 static int carp_dscp_sysctl(SYSCTL_HANDLER_ARGS); 214 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 215 216 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 217 "CARP"); 218 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 219 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 220 0, 0, carp_allow_sysctl, "I", 221 "Accept incoming CARP packets"); 222 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp, 223 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 224 0, 0, carp_dscp_sysctl, "I", 225 "DSCP value for carp packets"); 226 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 227 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 228 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 229 &VNET_NAME(carp_log), 0, "CARP log level"); 230 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 231 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 232 0, 0, carp_demote_adj_sysctl, "I", 233 "Adjust demotion factor (skew of advskew)"); 234 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 235 CTLFLAG_VNET | CTLFLAG_RW, 236 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 237 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 238 CTLFLAG_VNET | CTLFLAG_RW, 239 &VNET_NAME(carp_ifdown_adj), 0, 240 "Interface down demotion factor adjustment"); 241 242 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 243 VNET_PCPUSTAT_SYSINIT(carpstats); 244 VNET_PCPUSTAT_SYSUNINIT(carpstats); 245 246 #define CARPSTATS_ADD(name, val) \ 247 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 248 sizeof(uint64_t)], (val)) 249 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 250 251 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 252 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 253 254 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 255 NULL, MTX_DEF) 256 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 257 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 258 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 259 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 260 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 261 NULL, MTX_DEF) 262 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 263 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 264 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 265 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 266 #define CIF_FREE(cif) do { \ 267 CIF_LOCK(cif); \ 268 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 269 carp_free_if(cif); \ 270 else \ 271 CIF_UNLOCK(cif); \ 272 } while (0) 273 274 #define CARP_LOG(...) do { \ 275 if (V_carp_log > 0) \ 276 log(LOG_INFO, "carp: " __VA_ARGS__); \ 277 } while (0) 278 279 #define CARP_DEBUG(...) do { \ 280 if (V_carp_log > 1) \ 281 log(LOG_DEBUG, __VA_ARGS__); \ 282 } while (0) 283 284 #define IFNET_FOREACH_IFA(ifp, ifa) \ 285 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 286 if ((ifa)->ifa_carp != NULL) 287 288 #define CARP_FOREACH_IFA(sc, ifa) \ 289 CARP_LOCK_ASSERT(sc); \ 290 for (int _i = 0; \ 291 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 292 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 293 ++_i) 294 295 #define IFNET_FOREACH_CARP(ifp, sc) \ 296 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 297 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 298 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 299 300 #define DEMOTE_ADVSKEW(sc) \ 301 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 302 CARP_MAXSKEW : \ 303 (((sc)->sc_advskew + V_carp_demotion < 0) ? \ 304 0 : ((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 static 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 static 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 /* verify the CARP checksum */ 581 m->m_data += *offp; 582 if (in_cksum(m, sizeof(*ch))) { 583 CARPSTATS_INC(carps_badsum); 584 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 585 m->m_pkthdr.rcvif->if_xname); 586 m_freem(m); 587 return (IPPROTO_DONE); 588 } 589 m->m_data -= *offp; 590 591 carp_input_c(m, ch, AF_INET6); 592 return (IPPROTO_DONE); 593 } 594 #endif /* INET6 */ 595 596 /* 597 * This routine should not be necessary at all, but some switches 598 * (VMWare ESX vswitches) can echo our own packets back at us, 599 * and we must ignore them or they will cause us to drop out of 600 * MASTER mode. 601 * 602 * We cannot catch all cases of network loops. Instead, what we 603 * do here is catch any packet that arrives with a carp header 604 * with a VHID of 0, that comes from an address that is our own. 605 * These packets are by definition "from us" (even if they are from 606 * a misconfigured host that is pretending to be us). 607 * 608 * The VHID test is outside this mini-function. 609 */ 610 static int 611 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 612 { 613 #ifdef INET 614 struct ip *ip4; 615 struct in_addr in4; 616 #endif 617 #ifdef INET6 618 struct ip6_hdr *ip6; 619 struct in6_addr in6; 620 #endif 621 622 switch (af) { 623 #ifdef INET 624 case AF_INET: 625 ip4 = mtod(m, struct ip *); 626 in4 = ifatoia(ifa)->ia_addr.sin_addr; 627 return (in4.s_addr == ip4->ip_src.s_addr); 628 #endif 629 #ifdef INET6 630 case AF_INET6: 631 ip6 = mtod(m, struct ip6_hdr *); 632 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 633 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 634 #endif 635 default: 636 break; 637 } 638 return (0); 639 } 640 641 static void 642 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 643 { 644 struct ifnet *ifp = m->m_pkthdr.rcvif; 645 struct ifaddr *ifa, *match; 646 struct carp_softc *sc; 647 uint64_t tmp_counter; 648 struct timeval sc_tv, ch_tv; 649 int error; 650 651 NET_EPOCH_ASSERT(); 652 653 /* 654 * Verify that the VHID is valid on the receiving interface. 655 * 656 * There should be just one match. If there are none 657 * the VHID is not valid and we drop the packet. If 658 * there are multiple VHID matches, take just the first 659 * one, for compatibility with previous code. While we're 660 * scanning, check for obvious loops in the network topology 661 * (these should never happen, and as noted above, we may 662 * miss real loops; this is just a double-check). 663 */ 664 error = 0; 665 match = NULL; 666 IFNET_FOREACH_IFA(ifp, ifa) { 667 if (match == NULL && ifa->ifa_carp != NULL && 668 ifa->ifa_addr->sa_family == af && 669 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 670 match = ifa; 671 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 672 error = ELOOP; 673 } 674 ifa = error ? NULL : match; 675 if (ifa != NULL) 676 ifa_ref(ifa); 677 678 if (ifa == NULL) { 679 if (error == ELOOP) { 680 CARP_DEBUG("dropping looped packet on interface %s\n", 681 ifp->if_xname); 682 CARPSTATS_INC(carps_badif); /* ??? */ 683 } else { 684 CARPSTATS_INC(carps_badvhid); 685 } 686 m_freem(m); 687 return; 688 } 689 690 /* verify the CARP version. */ 691 if (ch->carp_version != CARP_VERSION) { 692 CARPSTATS_INC(carps_badver); 693 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 694 ch->carp_version); 695 ifa_free(ifa); 696 m_freem(m); 697 return; 698 } 699 700 sc = ifa->ifa_carp; 701 CARP_LOCK(sc); 702 ifa_free(ifa); 703 704 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 705 CARPSTATS_INC(carps_badauth); 706 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 707 sc->sc_vhid, ifp->if_xname); 708 goto out; 709 } 710 711 tmp_counter = ntohl(ch->carp_counter[0]); 712 tmp_counter = tmp_counter<<32; 713 tmp_counter += ntohl(ch->carp_counter[1]); 714 715 /* XXX Replay protection goes here */ 716 717 sc->sc_init_counter = 0; 718 sc->sc_counter = tmp_counter; 719 720 sc_tv.tv_sec = sc->sc_advbase; 721 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 722 ch_tv.tv_sec = ch->carp_advbase; 723 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 724 725 switch (sc->sc_state) { 726 case INIT: 727 break; 728 case MASTER: 729 /* 730 * If we receive an advertisement from a master who's going to 731 * be more frequent than us, go into BACKUP state. 732 */ 733 if (timevalcmp(&sc_tv, &ch_tv, >) || 734 timevalcmp(&sc_tv, &ch_tv, ==)) { 735 callout_stop(&sc->sc_ad_tmo); 736 carp_set_state(sc, BACKUP, 737 "more frequent advertisement received"); 738 carp_setrun(sc, 0); 739 carp_delroute(sc); 740 } 741 break; 742 case BACKUP: 743 /* 744 * If we're pre-empting masters who advertise slower than us, 745 * and this one claims to be slower, treat him as down. 746 */ 747 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 748 carp_master_down_locked(sc, 749 "preempting a slower master"); 750 break; 751 } 752 753 /* 754 * If the master is going to advertise at such a low frequency 755 * that he's guaranteed to time out, we'd might as well just 756 * treat him as timed out now. 757 */ 758 sc_tv.tv_sec = sc->sc_advbase * 3; 759 if (timevalcmp(&sc_tv, &ch_tv, <)) { 760 carp_master_down_locked(sc, "master will time out"); 761 break; 762 } 763 764 /* 765 * Otherwise, we reset the counter and wait for the next 766 * advertisement. 767 */ 768 carp_setrun(sc, af); 769 break; 770 } 771 772 out: 773 CARP_UNLOCK(sc); 774 m_freem(m); 775 } 776 777 static int 778 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 779 { 780 struct m_tag *mtag; 781 782 if (sc->sc_init_counter) { 783 /* this could also be seconds since unix epoch */ 784 sc->sc_counter = arc4random(); 785 sc->sc_counter = sc->sc_counter << 32; 786 sc->sc_counter += arc4random(); 787 } else 788 sc->sc_counter++; 789 790 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 791 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 792 793 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 794 795 /* Tag packet for carp_output */ 796 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 797 M_NOWAIT)) == NULL) { 798 m_freem(m); 799 CARPSTATS_INC(carps_onomem); 800 return (ENOMEM); 801 } 802 bcopy(&sc, mtag + 1, sizeof(sc)); 803 m_tag_prepend(m, mtag); 804 805 return (0); 806 } 807 808 /* 809 * To avoid LORs and possible recursions this function shouldn't 810 * be called directly, but scheduled via taskqueue. 811 */ 812 static void 813 carp_send_ad_all(void *ctx __unused, int pending __unused) 814 { 815 struct carp_softc *sc; 816 struct epoch_tracker et; 817 818 NET_EPOCH_ENTER(et); 819 mtx_lock(&carp_mtx); 820 LIST_FOREACH(sc, &carp_list, sc_next) 821 if (sc->sc_state == MASTER) { 822 CARP_LOCK(sc); 823 CURVNET_SET(sc->sc_carpdev->if_vnet); 824 carp_send_ad_locked(sc); 825 CURVNET_RESTORE(); 826 CARP_UNLOCK(sc); 827 } 828 mtx_unlock(&carp_mtx); 829 NET_EPOCH_EXIT(et); 830 } 831 832 /* Send a periodic advertisement, executed in callout context. */ 833 static void 834 carp_send_ad(void *v) 835 { 836 struct carp_softc *sc = v; 837 struct epoch_tracker et; 838 839 NET_EPOCH_ENTER(et); 840 CARP_LOCK_ASSERT(sc); 841 CURVNET_SET(sc->sc_carpdev->if_vnet); 842 carp_send_ad_locked(sc); 843 CURVNET_RESTORE(); 844 CARP_UNLOCK(sc); 845 NET_EPOCH_EXIT(et); 846 } 847 848 static void 849 carp_send_ad_error(struct carp_softc *sc, int error) 850 { 851 852 /* 853 * We track errors and successfull sends with this logic: 854 * - Any error resets success counter to 0. 855 * - MAX_ERRORS triggers demotion. 856 * - MIN_SUCCESS successes resets error counter to 0. 857 * - MIN_SUCCESS reverts demotion, if it was triggered before. 858 */ 859 if (error) { 860 if (sc->sc_sendad_errors < INT_MAX) 861 sc->sc_sendad_errors++; 862 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 863 static const char fmt[] = "send error %d on %s"; 864 char msg[sizeof(fmt) + IFNAMSIZ]; 865 866 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 867 carp_demote_adj(V_carp_senderr_adj, msg); 868 } 869 sc->sc_sendad_success = 0; 870 } else if (sc->sc_sendad_errors > 0) { 871 if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 872 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) { 873 static const char fmt[] = "send ok on %s"; 874 char msg[sizeof(fmt) + IFNAMSIZ]; 875 876 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 877 carp_demote_adj(-V_carp_senderr_adj, msg); 878 } 879 sc->sc_sendad_errors = 0; 880 } 881 } 882 } 883 884 /* 885 * Pick the best ifaddr on the given ifp for sending CARP 886 * advertisements. 887 * 888 * "Best" here is defined by ifa_preferred(). This function is much 889 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 890 * 891 * (This could be simplified to return the actual address, except that 892 * it has a different format in AF_INET and AF_INET6.) 893 */ 894 static struct ifaddr * 895 carp_best_ifa(int af, struct ifnet *ifp) 896 { 897 struct ifaddr *ifa, *best; 898 899 NET_EPOCH_ASSERT(); 900 901 if (af >= AF_MAX) 902 return (NULL); 903 best = NULL; 904 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 905 if (ifa->ifa_addr->sa_family == af && 906 (best == NULL || ifa_preferred(best, ifa))) 907 best = ifa; 908 } 909 if (best != NULL) 910 ifa_ref(best); 911 return (best); 912 } 913 914 static void 915 carp_send_ad_locked(struct carp_softc *sc) 916 { 917 struct carp_header ch; 918 struct timeval tv; 919 struct ifaddr *ifa; 920 struct carp_header *ch_ptr; 921 struct mbuf *m; 922 int len, advskew; 923 924 NET_EPOCH_ASSERT(); 925 CARP_LOCK_ASSERT(sc); 926 927 advskew = DEMOTE_ADVSKEW(sc); 928 tv.tv_sec = sc->sc_advbase; 929 tv.tv_usec = advskew * 1000000 / 256; 930 931 ch.carp_version = CARP_VERSION; 932 ch.carp_type = CARP_ADVERTISEMENT; 933 ch.carp_vhid = sc->sc_vhid; 934 ch.carp_advbase = sc->sc_advbase; 935 ch.carp_advskew = advskew; 936 ch.carp_authlen = 7; /* XXX DEFINE */ 937 ch.carp_pad1 = 0; /* must be zero */ 938 ch.carp_cksum = 0; 939 940 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 941 942 #ifdef INET 943 if (sc->sc_naddrs) { 944 struct ip *ip; 945 946 m = m_gethdr(M_NOWAIT, MT_DATA); 947 if (m == NULL) { 948 CARPSTATS_INC(carps_onomem); 949 goto resched; 950 } 951 len = sizeof(*ip) + sizeof(ch); 952 m->m_pkthdr.len = len; 953 m->m_pkthdr.rcvif = NULL; 954 m->m_len = len; 955 M_ALIGN(m, m->m_len); 956 m->m_flags |= M_MCAST; 957 ip = mtod(m, struct ip *); 958 ip->ip_v = IPVERSION; 959 ip->ip_hl = sizeof(*ip) >> 2; 960 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET; 961 ip->ip_len = htons(len); 962 ip->ip_off = htons(IP_DF); 963 ip->ip_ttl = CARP_DFLTTL; 964 ip->ip_p = IPPROTO_CARP; 965 ip->ip_sum = 0; 966 ip_fillid(ip); 967 968 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 969 if (ifa != NULL) { 970 ip->ip_src.s_addr = 971 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 972 ifa_free(ifa); 973 } else 974 ip->ip_src.s_addr = 0; 975 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 976 977 ch_ptr = (struct carp_header *)(&ip[1]); 978 bcopy(&ch, ch_ptr, sizeof(ch)); 979 if (carp_prepare_ad(m, sc, ch_ptr)) 980 goto resched; 981 982 m->m_data += sizeof(*ip); 983 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 984 m->m_data -= sizeof(*ip); 985 986 CARPSTATS_INC(carps_opackets); 987 988 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 989 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 990 } 991 #endif /* INET */ 992 #ifdef INET6 993 if (sc->sc_naddrs6) { 994 struct ip6_hdr *ip6; 995 996 m = m_gethdr(M_NOWAIT, MT_DATA); 997 if (m == NULL) { 998 CARPSTATS_INC(carps_onomem); 999 goto resched; 1000 } 1001 len = sizeof(*ip6) + sizeof(ch); 1002 m->m_pkthdr.len = len; 1003 m->m_pkthdr.rcvif = NULL; 1004 m->m_len = len; 1005 M_ALIGN(m, m->m_len); 1006 m->m_flags |= M_MCAST; 1007 ip6 = mtod(m, struct ip6_hdr *); 1008 bzero(ip6, sizeof(*ip6)); 1009 ip6->ip6_vfc |= IPV6_VERSION; 1010 /* Traffic class isn't defined in ip6 struct instead 1011 * it gets offset into flowid field */ 1012 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN + 1013 IPTOS_DSCP_OFFSET)); 1014 ip6->ip6_hlim = CARP_DFLTTL; 1015 ip6->ip6_nxt = IPPROTO_CARP; 1016 1017 /* set the source address */ 1018 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 1019 if (ifa != NULL) { 1020 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 1021 sizeof(struct in6_addr)); 1022 ifa_free(ifa); 1023 } else 1024 /* This should never happen with IPv6. */ 1025 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 1026 1027 /* Set the multicast destination. */ 1028 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1029 ip6->ip6_dst.s6_addr8[15] = 0x12; 1030 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1031 m_freem(m); 1032 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1033 goto resched; 1034 } 1035 1036 ch_ptr = (struct carp_header *)(&ip6[1]); 1037 bcopy(&ch, ch_ptr, sizeof(ch)); 1038 if (carp_prepare_ad(m, sc, ch_ptr)) 1039 goto resched; 1040 1041 m->m_data += sizeof(*ip6); 1042 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1043 m->m_data -= sizeof(*ip6); 1044 1045 CARPSTATS_INC(carps_opackets6); 1046 1047 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1048 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1049 } 1050 #endif /* INET6 */ 1051 1052 resched: 1053 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1054 } 1055 1056 static void 1057 carp_addroute(struct carp_softc *sc) 1058 { 1059 struct ifaddr *ifa; 1060 1061 CARP_FOREACH_IFA(sc, ifa) 1062 carp_ifa_addroute(ifa); 1063 } 1064 1065 static void 1066 carp_ifa_addroute(struct ifaddr *ifa) 1067 { 1068 1069 switch (ifa->ifa_addr->sa_family) { 1070 #ifdef INET 1071 case AF_INET: 1072 in_addprefix(ifatoia(ifa)); 1073 ifa_add_loopback_route(ifa, 1074 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1075 break; 1076 #endif 1077 #ifdef INET6 1078 case AF_INET6: 1079 ifa_add_loopback_route(ifa, 1080 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1081 nd6_add_ifa_lle(ifatoia6(ifa)); 1082 break; 1083 #endif 1084 } 1085 } 1086 1087 static void 1088 carp_delroute(struct carp_softc *sc) 1089 { 1090 struct ifaddr *ifa; 1091 1092 CARP_FOREACH_IFA(sc, ifa) 1093 carp_ifa_delroute(ifa); 1094 } 1095 1096 static void 1097 carp_ifa_delroute(struct ifaddr *ifa) 1098 { 1099 1100 switch (ifa->ifa_addr->sa_family) { 1101 #ifdef INET 1102 case AF_INET: 1103 ifa_del_loopback_route(ifa, 1104 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1105 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1106 break; 1107 #endif 1108 #ifdef INET6 1109 case AF_INET6: 1110 ifa_del_loopback_route(ifa, 1111 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1112 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1113 break; 1114 #endif 1115 } 1116 } 1117 1118 int 1119 carp_master(struct ifaddr *ifa) 1120 { 1121 struct carp_softc *sc = ifa->ifa_carp; 1122 1123 return (sc->sc_state == MASTER); 1124 } 1125 1126 #ifdef INET 1127 /* 1128 * Broadcast a gratuitous ARP request containing 1129 * the virtual router MAC address for each IP address 1130 * associated with the virtual router. 1131 */ 1132 static void 1133 carp_send_arp(struct carp_softc *sc) 1134 { 1135 struct ifaddr *ifa; 1136 struct in_addr addr; 1137 1138 NET_EPOCH_ASSERT(); 1139 1140 CARP_FOREACH_IFA(sc, ifa) { 1141 if (ifa->ifa_addr->sa_family != AF_INET) 1142 continue; 1143 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1144 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1145 } 1146 } 1147 1148 int 1149 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1150 { 1151 struct carp_softc *sc = ifa->ifa_carp; 1152 1153 if (sc->sc_state == MASTER) { 1154 *enaddr = LLADDR(&sc->sc_addr); 1155 return (1); 1156 } 1157 1158 return (0); 1159 } 1160 #endif 1161 1162 #ifdef INET6 1163 static void 1164 carp_send_na(struct carp_softc *sc) 1165 { 1166 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1167 struct ifaddr *ifa; 1168 struct in6_addr *in6; 1169 1170 CARP_FOREACH_IFA(sc, ifa) { 1171 if (ifa->ifa_addr->sa_family != AF_INET6) 1172 continue; 1173 1174 in6 = IFA_IN6(ifa); 1175 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1176 ND_NA_FLAG_OVERRIDE, 1, NULL); 1177 DELAY(1000); /* XXX */ 1178 } 1179 } 1180 1181 /* 1182 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1183 * matches and is not a carp address. Returns NULL otherwise. 1184 */ 1185 struct ifaddr * 1186 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1187 { 1188 struct ifaddr *ifa; 1189 1190 NET_EPOCH_ASSERT(); 1191 1192 ifa = NULL; 1193 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1194 if (ifa->ifa_addr->sa_family != AF_INET6) 1195 continue; 1196 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1197 continue; 1198 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1199 ifa = NULL; 1200 else 1201 ifa_ref(ifa); 1202 break; 1203 } 1204 1205 return (ifa); 1206 } 1207 1208 char * 1209 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1210 { 1211 struct ifaddr *ifa; 1212 1213 NET_EPOCH_ASSERT(); 1214 1215 IFNET_FOREACH_IFA(ifp, ifa) 1216 if (ifa->ifa_addr->sa_family == AF_INET6 && 1217 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1218 struct carp_softc *sc = ifa->ifa_carp; 1219 struct m_tag *mtag; 1220 1221 mtag = m_tag_get(PACKET_TAG_CARP, 1222 sizeof(struct carp_softc *), M_NOWAIT); 1223 if (mtag == NULL) 1224 /* Better a bit than nothing. */ 1225 return (LLADDR(&sc->sc_addr)); 1226 1227 bcopy(&sc, mtag + 1, sizeof(sc)); 1228 m_tag_prepend(m, mtag); 1229 1230 return (LLADDR(&sc->sc_addr)); 1231 } 1232 1233 return (NULL); 1234 } 1235 #endif /* INET6 */ 1236 1237 int 1238 carp_forus(struct ifnet *ifp, u_char *dhost) 1239 { 1240 struct carp_softc *sc; 1241 uint8_t *ena = dhost; 1242 1243 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1244 return (0); 1245 1246 CIF_LOCK(ifp->if_carp); 1247 IFNET_FOREACH_CARP(ifp, sc) { 1248 /* 1249 * CARP_LOCK() is not here, since would protect nothing, but 1250 * cause deadlock with if_bridge, calling this under its lock. 1251 */ 1252 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1253 ETHER_ADDR_LEN)) { 1254 CIF_UNLOCK(ifp->if_carp); 1255 return (1); 1256 } 1257 } 1258 CIF_UNLOCK(ifp->if_carp); 1259 1260 return (0); 1261 } 1262 1263 /* Master down timeout event, executed in callout context. */ 1264 static void 1265 carp_master_down(void *v) 1266 { 1267 struct carp_softc *sc = v; 1268 struct epoch_tracker et; 1269 1270 NET_EPOCH_ENTER(et); 1271 CARP_LOCK_ASSERT(sc); 1272 1273 CURVNET_SET(sc->sc_carpdev->if_vnet); 1274 if (sc->sc_state == BACKUP) { 1275 carp_master_down_locked(sc, "master timed out"); 1276 } 1277 CURVNET_RESTORE(); 1278 1279 CARP_UNLOCK(sc); 1280 NET_EPOCH_EXIT(et); 1281 } 1282 1283 static void 1284 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1285 { 1286 1287 NET_EPOCH_ASSERT(); 1288 CARP_LOCK_ASSERT(sc); 1289 1290 switch (sc->sc_state) { 1291 case BACKUP: 1292 carp_set_state(sc, MASTER, reason); 1293 carp_send_ad_locked(sc); 1294 #ifdef INET 1295 carp_send_arp(sc); 1296 #endif 1297 #ifdef INET6 1298 carp_send_na(sc); 1299 #endif 1300 carp_setrun(sc, 0); 1301 carp_addroute(sc); 1302 break; 1303 case INIT: 1304 case MASTER: 1305 #ifdef INVARIANTS 1306 panic("carp: VHID %u@%s: master_down event in %s state\n", 1307 sc->sc_vhid, 1308 sc->sc_carpdev->if_xname, 1309 sc->sc_state ? "MASTER" : "INIT"); 1310 #endif 1311 break; 1312 } 1313 } 1314 1315 /* 1316 * When in backup state, af indicates whether to reset the master down timer 1317 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1318 */ 1319 static void 1320 carp_setrun(struct carp_softc *sc, sa_family_t af) 1321 { 1322 struct timeval tv; 1323 1324 CARP_LOCK_ASSERT(sc); 1325 1326 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1327 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1328 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1329 !V_carp_allow) 1330 return; 1331 1332 switch (sc->sc_state) { 1333 case INIT: 1334 carp_set_state(sc, BACKUP, "initialization complete"); 1335 carp_setrun(sc, 0); 1336 break; 1337 case BACKUP: 1338 callout_stop(&sc->sc_ad_tmo); 1339 tv.tv_sec = 3 * sc->sc_advbase; 1340 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1341 switch (af) { 1342 #ifdef INET 1343 case AF_INET: 1344 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1345 carp_master_down, sc); 1346 break; 1347 #endif 1348 #ifdef INET6 1349 case AF_INET6: 1350 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1351 carp_master_down, sc); 1352 break; 1353 #endif 1354 default: 1355 #ifdef INET 1356 if (sc->sc_naddrs) 1357 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1358 carp_master_down, sc); 1359 #endif 1360 #ifdef INET6 1361 if (sc->sc_naddrs6) 1362 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1363 carp_master_down, sc); 1364 #endif 1365 break; 1366 } 1367 break; 1368 case MASTER: 1369 tv.tv_sec = sc->sc_advbase; 1370 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1371 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1372 carp_send_ad, sc); 1373 break; 1374 } 1375 } 1376 1377 /* 1378 * Setup multicast structures. 1379 */ 1380 static int 1381 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1382 { 1383 struct ifnet *ifp = cif->cif_ifp; 1384 int error = 0; 1385 1386 switch (sa) { 1387 #ifdef INET 1388 case AF_INET: 1389 { 1390 struct ip_moptions *imo = &cif->cif_imo; 1391 struct in_mfilter *imf; 1392 struct in_addr addr; 1393 1394 if (ip_mfilter_first(&imo->imo_head) != NULL) 1395 return (0); 1396 1397 imf = ip_mfilter_alloc(M_WAITOK, 0, 0); 1398 ip_mfilter_init(&imo->imo_head); 1399 imo->imo_multicast_vif = -1; 1400 1401 addr.s_addr = htonl(INADDR_CARP_GROUP); 1402 if ((error = in_joingroup(ifp, &addr, NULL, 1403 &imf->imf_inm)) != 0) { 1404 ip_mfilter_free(imf); 1405 break; 1406 } 1407 1408 ip_mfilter_insert(&imo->imo_head, imf); 1409 imo->imo_multicast_ifp = ifp; 1410 imo->imo_multicast_ttl = CARP_DFLTTL; 1411 imo->imo_multicast_loop = 0; 1412 break; 1413 } 1414 #endif 1415 #ifdef INET6 1416 case AF_INET6: 1417 { 1418 struct ip6_moptions *im6o = &cif->cif_im6o; 1419 struct in6_mfilter *im6f[2]; 1420 struct in6_addr in6; 1421 1422 if (ip6_mfilter_first(&im6o->im6o_head)) 1423 return (0); 1424 1425 im6f[0] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1426 im6f[1] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1427 1428 ip6_mfilter_init(&im6o->im6o_head); 1429 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1430 im6o->im6o_multicast_ifp = ifp; 1431 1432 /* Join IPv6 CARP multicast group. */ 1433 bzero(&in6, sizeof(in6)); 1434 in6.s6_addr16[0] = htons(0xff02); 1435 in6.s6_addr8[15] = 0x12; 1436 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1437 ip6_mfilter_free(im6f[0]); 1438 ip6_mfilter_free(im6f[1]); 1439 break; 1440 } 1441 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[0]->im6f_in6m, 0)) != 0) { 1442 ip6_mfilter_free(im6f[0]); 1443 ip6_mfilter_free(im6f[1]); 1444 break; 1445 } 1446 1447 /* Join solicited multicast address. */ 1448 bzero(&in6, sizeof(in6)); 1449 in6.s6_addr16[0] = htons(0xff02); 1450 in6.s6_addr32[1] = 0; 1451 in6.s6_addr32[2] = htonl(1); 1452 in6.s6_addr32[3] = 0; 1453 in6.s6_addr8[12] = 0xff; 1454 1455 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1456 ip6_mfilter_free(im6f[0]); 1457 ip6_mfilter_free(im6f[1]); 1458 break; 1459 } 1460 1461 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[1]->im6f_in6m, 0)) != 0) { 1462 in6_leavegroup(im6f[0]->im6f_in6m, NULL); 1463 ip6_mfilter_free(im6f[0]); 1464 ip6_mfilter_free(im6f[1]); 1465 break; 1466 } 1467 ip6_mfilter_insert(&im6o->im6o_head, im6f[0]); 1468 ip6_mfilter_insert(&im6o->im6o_head, im6f[1]); 1469 break; 1470 } 1471 #endif 1472 } 1473 1474 return (error); 1475 } 1476 1477 /* 1478 * Free multicast structures. 1479 */ 1480 static void 1481 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1482 { 1483 #ifdef INET 1484 struct ip_moptions *imo = &cif->cif_imo; 1485 struct in_mfilter *imf; 1486 #endif 1487 #ifdef INET6 1488 struct ip6_moptions *im6o = &cif->cif_im6o; 1489 struct in6_mfilter *im6f; 1490 #endif 1491 sx_assert(&carp_sx, SA_XLOCKED); 1492 1493 switch (sa) { 1494 #ifdef INET 1495 case AF_INET: 1496 if (cif->cif_naddrs != 0) 1497 break; 1498 1499 while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) { 1500 ip_mfilter_remove(&imo->imo_head, imf); 1501 in_leavegroup(imf->imf_inm, NULL); 1502 ip_mfilter_free(imf); 1503 } 1504 break; 1505 #endif 1506 #ifdef INET6 1507 case AF_INET6: 1508 if (cif->cif_naddrs6 != 0) 1509 break; 1510 1511 while ((im6f = ip6_mfilter_first(&im6o->im6o_head)) != NULL) { 1512 ip6_mfilter_remove(&im6o->im6o_head, im6f); 1513 in6_leavegroup(im6f->im6f_in6m, NULL); 1514 ip6_mfilter_free(im6f); 1515 } 1516 break; 1517 #endif 1518 } 1519 } 1520 1521 int 1522 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1523 { 1524 struct m_tag *mtag; 1525 struct carp_softc *sc; 1526 1527 if (!sa) 1528 return (0); 1529 1530 switch (sa->sa_family) { 1531 #ifdef INET 1532 case AF_INET: 1533 break; 1534 #endif 1535 #ifdef INET6 1536 case AF_INET6: 1537 break; 1538 #endif 1539 default: 1540 return (0); 1541 } 1542 1543 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1544 if (mtag == NULL) 1545 return (0); 1546 1547 bcopy(mtag + 1, &sc, sizeof(sc)); 1548 1549 /* Set the source MAC address to the Virtual Router MAC Address. */ 1550 switch (ifp->if_type) { 1551 case IFT_ETHER: 1552 case IFT_BRIDGE: 1553 case IFT_L2VLAN: { 1554 struct ether_header *eh; 1555 1556 eh = mtod(m, struct ether_header *); 1557 eh->ether_shost[0] = 0; 1558 eh->ether_shost[1] = 0; 1559 eh->ether_shost[2] = 0x5e; 1560 eh->ether_shost[3] = 0; 1561 eh->ether_shost[4] = 1; 1562 eh->ether_shost[5] = sc->sc_vhid; 1563 } 1564 break; 1565 default: 1566 printf("%s: carp is not supported for the %d interface type\n", 1567 ifp->if_xname, ifp->if_type); 1568 return (EOPNOTSUPP); 1569 } 1570 1571 return (0); 1572 } 1573 1574 static struct carp_softc* 1575 carp_alloc(struct ifnet *ifp) 1576 { 1577 struct carp_softc *sc; 1578 struct carp_if *cif; 1579 1580 sx_assert(&carp_sx, SA_XLOCKED); 1581 1582 if ((cif = ifp->if_carp) == NULL) 1583 cif = carp_alloc_if(ifp); 1584 1585 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1586 1587 sc->sc_advbase = CARP_DFLTINTV; 1588 sc->sc_vhid = -1; /* required setting */ 1589 sc->sc_init_counter = 1; 1590 sc->sc_state = INIT; 1591 1592 sc->sc_ifasiz = sizeof(struct ifaddr *); 1593 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1594 sc->sc_carpdev = ifp; 1595 1596 CARP_LOCK_INIT(sc); 1597 #ifdef INET 1598 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1599 #endif 1600 #ifdef INET6 1601 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1602 #endif 1603 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1604 1605 CIF_LOCK(cif); 1606 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1607 CIF_UNLOCK(cif); 1608 1609 mtx_lock(&carp_mtx); 1610 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1611 mtx_unlock(&carp_mtx); 1612 1613 return (sc); 1614 } 1615 1616 static void 1617 carp_grow_ifas(struct carp_softc *sc) 1618 { 1619 struct ifaddr **new; 1620 1621 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1622 CARP_LOCK(sc); 1623 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1624 free(sc->sc_ifas, M_CARP); 1625 sc->sc_ifas = new; 1626 sc->sc_ifasiz *= 2; 1627 CARP_UNLOCK(sc); 1628 } 1629 1630 static void 1631 carp_destroy(struct carp_softc *sc) 1632 { 1633 struct ifnet *ifp = sc->sc_carpdev; 1634 struct carp_if *cif = ifp->if_carp; 1635 1636 sx_assert(&carp_sx, SA_XLOCKED); 1637 1638 if (sc->sc_suppress) 1639 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1640 CARP_UNLOCK(sc); 1641 1642 CIF_LOCK(cif); 1643 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1644 CIF_UNLOCK(cif); 1645 1646 mtx_lock(&carp_mtx); 1647 LIST_REMOVE(sc, sc_next); 1648 mtx_unlock(&carp_mtx); 1649 1650 callout_drain(&sc->sc_ad_tmo); 1651 #ifdef INET 1652 callout_drain(&sc->sc_md_tmo); 1653 #endif 1654 #ifdef INET6 1655 callout_drain(&sc->sc_md6_tmo); 1656 #endif 1657 CARP_LOCK_DESTROY(sc); 1658 1659 free(sc->sc_ifas, M_CARP); 1660 free(sc, M_CARP); 1661 } 1662 1663 static struct carp_if* 1664 carp_alloc_if(struct ifnet *ifp) 1665 { 1666 struct carp_if *cif; 1667 int error; 1668 1669 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1670 1671 if ((error = ifpromisc(ifp, 1)) != 0) 1672 printf("%s: ifpromisc(%s) failed: %d\n", 1673 __func__, ifp->if_xname, error); 1674 else 1675 cif->cif_flags |= CIF_PROMISC; 1676 1677 CIF_LOCK_INIT(cif); 1678 cif->cif_ifp = ifp; 1679 TAILQ_INIT(&cif->cif_vrs); 1680 1681 IF_ADDR_WLOCK(ifp); 1682 ifp->if_carp = cif; 1683 if_ref(ifp); 1684 IF_ADDR_WUNLOCK(ifp); 1685 1686 return (cif); 1687 } 1688 1689 static void 1690 carp_free_if(struct carp_if *cif) 1691 { 1692 struct ifnet *ifp = cif->cif_ifp; 1693 1694 CIF_LOCK_ASSERT(cif); 1695 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1696 __func__)); 1697 1698 IF_ADDR_WLOCK(ifp); 1699 ifp->if_carp = NULL; 1700 IF_ADDR_WUNLOCK(ifp); 1701 1702 CIF_LOCK_DESTROY(cif); 1703 1704 if (cif->cif_flags & CIF_PROMISC) 1705 ifpromisc(ifp, 0); 1706 if_rele(ifp); 1707 1708 free(cif, M_CARP); 1709 } 1710 1711 static void 1712 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1713 { 1714 1715 CARP_LOCK(sc); 1716 carpr->carpr_state = sc->sc_state; 1717 carpr->carpr_vhid = sc->sc_vhid; 1718 carpr->carpr_advbase = sc->sc_advbase; 1719 carpr->carpr_advskew = sc->sc_advskew; 1720 if (priv) 1721 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1722 else 1723 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1724 CARP_UNLOCK(sc); 1725 } 1726 1727 int 1728 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1729 { 1730 struct carpreq carpr; 1731 struct ifnet *ifp; 1732 struct carp_softc *sc = NULL; 1733 int error = 0, locked = 0; 1734 1735 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1736 return (error); 1737 1738 ifp = ifunit_ref(ifr->ifr_name); 1739 if (ifp == NULL) 1740 return (ENXIO); 1741 1742 switch (ifp->if_type) { 1743 case IFT_ETHER: 1744 case IFT_L2VLAN: 1745 case IFT_BRIDGE: 1746 break; 1747 default: 1748 error = EOPNOTSUPP; 1749 goto out; 1750 } 1751 1752 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1753 error = EADDRNOTAVAIL; 1754 goto out; 1755 } 1756 1757 sx_xlock(&carp_sx); 1758 switch (cmd) { 1759 case SIOCSVH: 1760 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1761 break; 1762 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1763 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1764 error = EINVAL; 1765 break; 1766 } 1767 1768 if (ifp->if_carp) { 1769 IFNET_FOREACH_CARP(ifp, sc) 1770 if (sc->sc_vhid == carpr.carpr_vhid) 1771 break; 1772 } 1773 if (sc == NULL) { 1774 sc = carp_alloc(ifp); 1775 CARP_LOCK(sc); 1776 sc->sc_vhid = carpr.carpr_vhid; 1777 LLADDR(&sc->sc_addr)[0] = 0; 1778 LLADDR(&sc->sc_addr)[1] = 0; 1779 LLADDR(&sc->sc_addr)[2] = 0x5e; 1780 LLADDR(&sc->sc_addr)[3] = 0; 1781 LLADDR(&sc->sc_addr)[4] = 1; 1782 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1783 } else 1784 CARP_LOCK(sc); 1785 locked = 1; 1786 if (carpr.carpr_advbase > 0) { 1787 if (carpr.carpr_advbase > 255 || 1788 carpr.carpr_advbase < CARP_DFLTINTV) { 1789 error = EINVAL; 1790 break; 1791 } 1792 sc->sc_advbase = carpr.carpr_advbase; 1793 } 1794 if (carpr.carpr_advskew >= 255) { 1795 error = EINVAL; 1796 break; 1797 } 1798 sc->sc_advskew = carpr.carpr_advskew; 1799 if (carpr.carpr_key[0] != '\0') { 1800 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1801 carp_hmac_prepare(sc); 1802 } 1803 if (sc->sc_state != INIT && 1804 carpr.carpr_state != sc->sc_state) { 1805 switch (carpr.carpr_state) { 1806 case BACKUP: 1807 callout_stop(&sc->sc_ad_tmo); 1808 carp_set_state(sc, BACKUP, 1809 "user requested via ifconfig"); 1810 carp_setrun(sc, 0); 1811 carp_delroute(sc); 1812 break; 1813 case MASTER: 1814 carp_master_down_locked(sc, 1815 "user requested via ifconfig"); 1816 break; 1817 default: 1818 break; 1819 } 1820 } 1821 break; 1822 1823 case SIOCGVH: 1824 { 1825 int priveleged; 1826 1827 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1828 error = EINVAL; 1829 break; 1830 } 1831 if (carpr.carpr_count < 1) { 1832 error = EMSGSIZE; 1833 break; 1834 } 1835 if (ifp->if_carp == NULL) { 1836 error = ENOENT; 1837 break; 1838 } 1839 1840 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1841 if (carpr.carpr_vhid != 0) { 1842 IFNET_FOREACH_CARP(ifp, sc) 1843 if (sc->sc_vhid == carpr.carpr_vhid) 1844 break; 1845 if (sc == NULL) { 1846 error = ENOENT; 1847 break; 1848 } 1849 carp_carprcp(&carpr, sc, priveleged); 1850 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1851 sizeof(carpr)); 1852 } else { 1853 int i, count; 1854 1855 count = 0; 1856 IFNET_FOREACH_CARP(ifp, sc) 1857 count++; 1858 1859 if (count > carpr.carpr_count) { 1860 CIF_UNLOCK(ifp->if_carp); 1861 error = EMSGSIZE; 1862 break; 1863 } 1864 1865 i = 0; 1866 IFNET_FOREACH_CARP(ifp, sc) { 1867 carp_carprcp(&carpr, sc, priveleged); 1868 carpr.carpr_count = count; 1869 error = copyout(&carpr, 1870 (char *)ifr_data_get_ptr(ifr) + 1871 (i * sizeof(carpr)), sizeof(carpr)); 1872 if (error) { 1873 CIF_UNLOCK(ifp->if_carp); 1874 break; 1875 } 1876 i++; 1877 } 1878 } 1879 break; 1880 } 1881 default: 1882 error = EINVAL; 1883 } 1884 sx_xunlock(&carp_sx); 1885 1886 out: 1887 if (locked) 1888 CARP_UNLOCK(sc); 1889 if_rele(ifp); 1890 1891 return (error); 1892 } 1893 1894 static int 1895 carp_get_vhid(struct ifaddr *ifa) 1896 { 1897 1898 if (ifa == NULL || ifa->ifa_carp == NULL) 1899 return (0); 1900 1901 return (ifa->ifa_carp->sc_vhid); 1902 } 1903 1904 int 1905 carp_attach(struct ifaddr *ifa, int vhid) 1906 { 1907 struct ifnet *ifp = ifa->ifa_ifp; 1908 struct carp_if *cif = ifp->if_carp; 1909 struct carp_softc *sc; 1910 int index, error; 1911 1912 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1913 1914 switch (ifa->ifa_addr->sa_family) { 1915 #ifdef INET 1916 case AF_INET: 1917 #endif 1918 #ifdef INET6 1919 case AF_INET6: 1920 #endif 1921 break; 1922 default: 1923 return (EPROTOTYPE); 1924 } 1925 1926 sx_xlock(&carp_sx); 1927 if (ifp->if_carp == NULL) { 1928 sx_xunlock(&carp_sx); 1929 return (ENOPROTOOPT); 1930 } 1931 1932 IFNET_FOREACH_CARP(ifp, sc) 1933 if (sc->sc_vhid == vhid) 1934 break; 1935 if (sc == NULL) { 1936 sx_xunlock(&carp_sx); 1937 return (ENOENT); 1938 } 1939 1940 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1941 if (error) { 1942 CIF_FREE(cif); 1943 sx_xunlock(&carp_sx); 1944 return (error); 1945 } 1946 1947 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1948 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1949 carp_grow_ifas(sc); 1950 1951 switch (ifa->ifa_addr->sa_family) { 1952 #ifdef INET 1953 case AF_INET: 1954 cif->cif_naddrs++; 1955 sc->sc_naddrs++; 1956 break; 1957 #endif 1958 #ifdef INET6 1959 case AF_INET6: 1960 cif->cif_naddrs6++; 1961 sc->sc_naddrs6++; 1962 break; 1963 #endif 1964 } 1965 1966 ifa_ref(ifa); 1967 1968 CARP_LOCK(sc); 1969 sc->sc_ifas[index - 1] = ifa; 1970 ifa->ifa_carp = sc; 1971 carp_hmac_prepare(sc); 1972 carp_sc_state(sc); 1973 CARP_UNLOCK(sc); 1974 1975 sx_xunlock(&carp_sx); 1976 1977 return (0); 1978 } 1979 1980 void 1981 carp_detach(struct ifaddr *ifa, bool keep_cif) 1982 { 1983 struct ifnet *ifp = ifa->ifa_ifp; 1984 struct carp_if *cif = ifp->if_carp; 1985 struct carp_softc *sc = ifa->ifa_carp; 1986 int i, index; 1987 1988 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1989 1990 sx_xlock(&carp_sx); 1991 1992 CARP_LOCK(sc); 1993 /* Shift array. */ 1994 index = sc->sc_naddrs + sc->sc_naddrs6; 1995 for (i = 0; i < index; i++) 1996 if (sc->sc_ifas[i] == ifa) 1997 break; 1998 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1999 for (; i < index - 1; i++) 2000 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 2001 sc->sc_ifas[index - 1] = NULL; 2002 2003 switch (ifa->ifa_addr->sa_family) { 2004 #ifdef INET 2005 case AF_INET: 2006 cif->cif_naddrs--; 2007 sc->sc_naddrs--; 2008 break; 2009 #endif 2010 #ifdef INET6 2011 case AF_INET6: 2012 cif->cif_naddrs6--; 2013 sc->sc_naddrs6--; 2014 break; 2015 #endif 2016 } 2017 2018 carp_ifa_delroute(ifa); 2019 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 2020 2021 ifa->ifa_carp = NULL; 2022 ifa_free(ifa); 2023 2024 carp_hmac_prepare(sc); 2025 carp_sc_state(sc); 2026 2027 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2028 carp_destroy(sc); 2029 else 2030 CARP_UNLOCK(sc); 2031 2032 if (!keep_cif) 2033 CIF_FREE(cif); 2034 2035 sx_xunlock(&carp_sx); 2036 } 2037 2038 static void 2039 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2040 { 2041 2042 CARP_LOCK_ASSERT(sc); 2043 2044 if (sc->sc_state != state) { 2045 const char *carp_states[] = { CARP_STATES }; 2046 char subsys[IFNAMSIZ+5]; 2047 2048 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2049 sc->sc_carpdev->if_xname); 2050 2051 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2052 carp_states[sc->sc_state], carp_states[state], reason); 2053 2054 sc->sc_state = state; 2055 2056 devctl_notify("CARP", subsys, carp_states[state], NULL); 2057 } 2058 } 2059 2060 static void 2061 carp_linkstate(struct ifnet *ifp) 2062 { 2063 struct carp_softc *sc; 2064 2065 CIF_LOCK(ifp->if_carp); 2066 IFNET_FOREACH_CARP(ifp, sc) { 2067 CARP_LOCK(sc); 2068 carp_sc_state(sc); 2069 CARP_UNLOCK(sc); 2070 } 2071 CIF_UNLOCK(ifp->if_carp); 2072 } 2073 2074 static void 2075 carp_sc_state(struct carp_softc *sc) 2076 { 2077 2078 CARP_LOCK_ASSERT(sc); 2079 2080 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2081 !(sc->sc_carpdev->if_flags & IFF_UP) || 2082 !V_carp_allow) { 2083 callout_stop(&sc->sc_ad_tmo); 2084 #ifdef INET 2085 callout_stop(&sc->sc_md_tmo); 2086 #endif 2087 #ifdef INET6 2088 callout_stop(&sc->sc_md6_tmo); 2089 #endif 2090 carp_set_state(sc, INIT, "hardware interface down"); 2091 carp_setrun(sc, 0); 2092 if (!sc->sc_suppress) 2093 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2094 sc->sc_suppress = 1; 2095 } else { 2096 carp_set_state(sc, INIT, "hardware interface up"); 2097 carp_setrun(sc, 0); 2098 if (sc->sc_suppress) 2099 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2100 sc->sc_suppress = 0; 2101 } 2102 } 2103 2104 static void 2105 carp_demote_adj(int adj, char *reason) 2106 { 2107 atomic_add_int(&V_carp_demotion, adj); 2108 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2109 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2110 } 2111 2112 static int 2113 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2114 { 2115 int new, error; 2116 struct carp_softc *sc; 2117 2118 new = V_carp_allow; 2119 error = sysctl_handle_int(oidp, &new, 0, req); 2120 if (error || !req->newptr) 2121 return (error); 2122 2123 if (V_carp_allow != new) { 2124 V_carp_allow = new; 2125 2126 mtx_lock(&carp_mtx); 2127 LIST_FOREACH(sc, &carp_list, sc_next) { 2128 CARP_LOCK(sc); 2129 if (curvnet == sc->sc_carpdev->if_vnet) 2130 carp_sc_state(sc); 2131 CARP_UNLOCK(sc); 2132 } 2133 mtx_unlock(&carp_mtx); 2134 } 2135 2136 return (0); 2137 } 2138 2139 static int 2140 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS) 2141 { 2142 int new, error; 2143 2144 new = V_carp_dscp; 2145 error = sysctl_handle_int(oidp, &new, 0, req); 2146 if (error || !req->newptr) 2147 return (error); 2148 2149 if (new < 0 || new > 63) 2150 return (EINVAL); 2151 2152 V_carp_dscp = new; 2153 2154 return (0); 2155 } 2156 2157 static int 2158 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2159 { 2160 int new, error; 2161 2162 new = V_carp_demotion; 2163 error = sysctl_handle_int(oidp, &new, 0, req); 2164 if (error || !req->newptr) 2165 return (error); 2166 2167 carp_demote_adj(new, "sysctl"); 2168 2169 return (0); 2170 } 2171 2172 static void 2173 carp_mod_cleanup(void) 2174 { 2175 2176 #ifdef INET 2177 (void)ipproto_unregister(IPPROTO_CARP); 2178 carp_iamatch_p = NULL; 2179 #endif 2180 #ifdef INET6 2181 (void)ip6proto_unregister(IPPROTO_CARP); 2182 carp_iamatch6_p = NULL; 2183 carp_macmatch6_p = NULL; 2184 #endif 2185 carp_ioctl_p = NULL; 2186 carp_attach_p = NULL; 2187 carp_detach_p = NULL; 2188 carp_get_vhid_p = NULL; 2189 carp_linkstate_p = NULL; 2190 carp_forus_p = NULL; 2191 carp_output_p = NULL; 2192 carp_demote_adj_p = NULL; 2193 carp_master_p = NULL; 2194 mtx_unlock(&carp_mtx); 2195 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2196 mtx_destroy(&carp_mtx); 2197 sx_destroy(&carp_sx); 2198 } 2199 2200 static int 2201 carp_mod_load(void) 2202 { 2203 int err; 2204 2205 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2206 sx_init(&carp_sx, "carp_sx"); 2207 LIST_INIT(&carp_list); 2208 carp_get_vhid_p = carp_get_vhid; 2209 carp_forus_p = carp_forus; 2210 carp_output_p = carp_output; 2211 carp_linkstate_p = carp_linkstate; 2212 carp_ioctl_p = carp_ioctl; 2213 carp_attach_p = carp_attach; 2214 carp_detach_p = carp_detach; 2215 carp_demote_adj_p = carp_demote_adj; 2216 carp_master_p = carp_master; 2217 #ifdef INET6 2218 carp_iamatch6_p = carp_iamatch6; 2219 carp_macmatch6_p = carp_macmatch6; 2220 err = ip6proto_register(IPPROTO_CARP, carp6_input, NULL); 2221 if (err) { 2222 printf("carp: error %d registering with INET6\n", err); 2223 carp_mod_cleanup(); 2224 return (err); 2225 } 2226 #endif 2227 #ifdef INET 2228 carp_iamatch_p = carp_iamatch; 2229 err = ipproto_register(IPPROTO_CARP, carp_input, NULL); 2230 if (err) { 2231 printf("carp: error %d registering with INET\n", err); 2232 carp_mod_cleanup(); 2233 return (err); 2234 } 2235 #endif 2236 return (0); 2237 } 2238 2239 static int 2240 carp_modevent(module_t mod, int type, void *data) 2241 { 2242 switch (type) { 2243 case MOD_LOAD: 2244 return carp_mod_load(); 2245 /* NOTREACHED */ 2246 case MOD_UNLOAD: 2247 mtx_lock(&carp_mtx); 2248 if (LIST_EMPTY(&carp_list)) 2249 carp_mod_cleanup(); 2250 else { 2251 mtx_unlock(&carp_mtx); 2252 return (EBUSY); 2253 } 2254 break; 2255 2256 default: 2257 return (EINVAL); 2258 } 2259 2260 return (0); 2261 } 2262 2263 static moduledata_t carp_mod = { 2264 "carp", 2265 carp_modevent, 2266 0 2267 }; 2268 2269 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2270