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 static VNET_DEFINE(int, carp_allow) = 1; 191 #define V_carp_allow VNET(carp_allow) 192 193 /* Preempt slower nodes. */ 194 static VNET_DEFINE(int, carp_preempt) = 0; 195 #define V_carp_preempt VNET(carp_preempt) 196 197 /* Log level. */ 198 static VNET_DEFINE(int, carp_log) = 1; 199 #define V_carp_log VNET(carp_log) 200 201 /* Global advskew demotion. */ 202 static VNET_DEFINE(int, carp_demotion) = 0; 203 #define V_carp_demotion VNET(carp_demotion) 204 205 /* Send error demotion factor. */ 206 static VNET_DEFINE(int, carp_senderr_adj) = CARP_MAXSKEW; 207 #define V_carp_senderr_adj VNET(carp_senderr_adj) 208 209 /* Iface down demotion factor. */ 210 static VNET_DEFINE(int, carp_ifdown_adj) = CARP_MAXSKEW; 211 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 212 213 static int carp_allow_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, 0, "CARP"); 217 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 218 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_allow_sysctl, "I", 219 "Accept incoming CARP packets"); 220 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 221 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 222 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 223 &VNET_NAME(carp_log), 0, "CARP log level"); 224 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 225 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 226 0, 0, carp_demote_adj_sysctl, "I", 227 "Adjust demotion factor (skew of advskew)"); 228 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 229 CTLFLAG_VNET | CTLFLAG_RW, 230 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 231 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 232 CTLFLAG_VNET | CTLFLAG_RW, 233 &VNET_NAME(carp_ifdown_adj), 0, 234 "Interface down demotion factor adjustment"); 235 236 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 237 VNET_PCPUSTAT_SYSINIT(carpstats); 238 VNET_PCPUSTAT_SYSUNINIT(carpstats); 239 240 #define CARPSTATS_ADD(name, val) \ 241 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 242 sizeof(uint64_t)], (val)) 243 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 244 245 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 246 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 247 248 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 249 NULL, MTX_DEF) 250 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 251 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 252 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 253 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 254 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 255 NULL, MTX_DEF) 256 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 257 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 258 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 259 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 260 #define CIF_FREE(cif) do { \ 261 CIF_LOCK(cif); \ 262 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 263 carp_free_if(cif); \ 264 else \ 265 CIF_UNLOCK(cif); \ 266 } while (0) 267 268 #define CARP_LOG(...) do { \ 269 if (V_carp_log > 0) \ 270 log(LOG_INFO, "carp: " __VA_ARGS__); \ 271 } while (0) 272 273 #define CARP_DEBUG(...) do { \ 274 if (V_carp_log > 1) \ 275 log(LOG_DEBUG, __VA_ARGS__); \ 276 } while (0) 277 278 #define IFNET_FOREACH_IFA(ifp, ifa) \ 279 IF_ADDR_LOCK_ASSERT(ifp); \ 280 TAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 281 if ((ifa)->ifa_carp != NULL) 282 283 #define CARP_FOREACH_IFA(sc, ifa) \ 284 CARP_LOCK_ASSERT(sc); \ 285 for (int _i = 0; \ 286 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 287 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 288 ++_i) 289 290 #define IFNET_FOREACH_CARP(ifp, sc) \ 291 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 292 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 293 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 294 295 #define DEMOTE_ADVSKEW(sc) \ 296 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 297 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) 298 299 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 300 static struct carp_softc 301 *carp_alloc(struct ifnet *); 302 static void carp_destroy(struct carp_softc *); 303 static struct carp_if 304 *carp_alloc_if(struct ifnet *); 305 static void carp_free_if(struct carp_if *); 306 static void carp_set_state(struct carp_softc *, int, const char* reason); 307 static void carp_sc_state(struct carp_softc *); 308 static void carp_setrun(struct carp_softc *, sa_family_t); 309 static void carp_master_down(void *); 310 static void carp_master_down_locked(struct carp_softc *, 311 const char* reason); 312 static void carp_send_ad(void *); 313 static void carp_send_ad_locked(struct carp_softc *); 314 static void carp_addroute(struct carp_softc *); 315 static void carp_ifa_addroute(struct ifaddr *); 316 static void carp_delroute(struct carp_softc *); 317 static void carp_ifa_delroute(struct ifaddr *); 318 static void carp_send_ad_all(void *, int); 319 static void carp_demote_adj(int, char *); 320 321 static LIST_HEAD(, carp_softc) carp_list; 322 static struct mtx carp_mtx; 323 static struct sx carp_sx; 324 static struct task carp_sendall_task = 325 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 326 327 static void 328 carp_hmac_prepare(struct carp_softc *sc) 329 { 330 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 331 uint8_t vhid = sc->sc_vhid & 0xff; 332 struct ifaddr *ifa; 333 int i, found; 334 #ifdef INET 335 struct in_addr last, cur, in; 336 #endif 337 #ifdef INET6 338 struct in6_addr last6, cur6, in6; 339 #endif 340 341 CARP_LOCK_ASSERT(sc); 342 343 /* Compute ipad from key. */ 344 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 345 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 346 for (i = 0; i < sizeof(sc->sc_pad); i++) 347 sc->sc_pad[i] ^= 0x36; 348 349 /* Precompute first part of inner hash. */ 350 SHA1Init(&sc->sc_sha1); 351 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 352 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 353 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 354 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 355 #ifdef INET 356 cur.s_addr = 0; 357 do { 358 found = 0; 359 last = cur; 360 cur.s_addr = 0xffffffff; 361 CARP_FOREACH_IFA(sc, ifa) { 362 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 363 if (ifa->ifa_addr->sa_family == AF_INET && 364 ntohl(in.s_addr) > ntohl(last.s_addr) && 365 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 366 cur.s_addr = in.s_addr; 367 found++; 368 } 369 } 370 if (found) 371 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 372 } while (found); 373 #endif /* INET */ 374 #ifdef INET6 375 memset(&cur6, 0, sizeof(cur6)); 376 do { 377 found = 0; 378 last6 = cur6; 379 memset(&cur6, 0xff, sizeof(cur6)); 380 CARP_FOREACH_IFA(sc, ifa) { 381 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 382 if (IN6_IS_SCOPE_EMBED(&in6)) 383 in6.s6_addr16[1] = 0; 384 if (ifa->ifa_addr->sa_family == AF_INET6 && 385 memcmp(&in6, &last6, sizeof(in6)) > 0 && 386 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 387 cur6 = in6; 388 found++; 389 } 390 } 391 if (found) 392 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 393 } while (found); 394 #endif /* INET6 */ 395 396 /* convert ipad to opad */ 397 for (i = 0; i < sizeof(sc->sc_pad); i++) 398 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 399 } 400 401 static void 402 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 403 unsigned char md[20]) 404 { 405 SHA1_CTX sha1ctx; 406 407 CARP_LOCK_ASSERT(sc); 408 409 /* fetch first half of inner hash */ 410 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 411 412 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 413 SHA1Final(md, &sha1ctx); 414 415 /* outer hash */ 416 SHA1Init(&sha1ctx); 417 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 418 SHA1Update(&sha1ctx, md, 20); 419 SHA1Final(md, &sha1ctx); 420 } 421 422 static int 423 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 424 unsigned char md[20]) 425 { 426 unsigned char md2[20]; 427 428 CARP_LOCK_ASSERT(sc); 429 430 carp_hmac_generate(sc, counter, md2); 431 432 return (bcmp(md, md2, sizeof(md2))); 433 } 434 435 /* 436 * process input packet. 437 * we have rearranged checks order compared to the rfc, 438 * but it seems more efficient this way or not possible otherwise. 439 */ 440 #ifdef INET 441 int 442 carp_input(struct mbuf **mp, int *offp, int proto) 443 { 444 struct mbuf *m = *mp; 445 struct ip *ip = mtod(m, struct ip *); 446 struct carp_header *ch; 447 int iplen, len; 448 449 iplen = *offp; 450 *mp = NULL; 451 452 CARPSTATS_INC(carps_ipackets); 453 454 if (!V_carp_allow) { 455 m_freem(m); 456 return (IPPROTO_DONE); 457 } 458 459 /* verify that the IP TTL is 255. */ 460 if (ip->ip_ttl != CARP_DFLTTL) { 461 CARPSTATS_INC(carps_badttl); 462 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 463 ip->ip_ttl, 464 m->m_pkthdr.rcvif->if_xname); 465 m_freem(m); 466 return (IPPROTO_DONE); 467 } 468 469 iplen = ip->ip_hl << 2; 470 471 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 472 CARPSTATS_INC(carps_badlen); 473 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 474 "on %s\n", __func__, m->m_len - sizeof(struct ip), 475 m->m_pkthdr.rcvif->if_xname); 476 m_freem(m); 477 return (IPPROTO_DONE); 478 } 479 480 if (iplen + sizeof(*ch) < m->m_len) { 481 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 482 CARPSTATS_INC(carps_hdrops); 483 CARP_DEBUG("%s: pullup failed\n", __func__); 484 return (IPPROTO_DONE); 485 } 486 ip = mtod(m, struct ip *); 487 } 488 ch = (struct carp_header *)((char *)ip + iplen); 489 490 /* 491 * verify that the received packet length is 492 * equal to the CARP header 493 */ 494 len = iplen + sizeof(*ch); 495 if (len > m->m_pkthdr.len) { 496 CARPSTATS_INC(carps_badlen); 497 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 498 m->m_pkthdr.len, 499 m->m_pkthdr.rcvif->if_xname); 500 m_freem(m); 501 return (IPPROTO_DONE); 502 } 503 504 if ((m = m_pullup(m, len)) == NULL) { 505 CARPSTATS_INC(carps_hdrops); 506 return (IPPROTO_DONE); 507 } 508 ip = mtod(m, struct ip *); 509 ch = (struct carp_header *)((char *)ip + iplen); 510 511 /* verify the CARP checksum */ 512 m->m_data += iplen; 513 if (in_cksum(m, len - iplen)) { 514 CARPSTATS_INC(carps_badsum); 515 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 516 m->m_pkthdr.rcvif->if_xname); 517 m_freem(m); 518 return (IPPROTO_DONE); 519 } 520 m->m_data -= iplen; 521 522 carp_input_c(m, ch, AF_INET); 523 return (IPPROTO_DONE); 524 } 525 #endif 526 527 #ifdef INET6 528 int 529 carp6_input(struct mbuf **mp, int *offp, int proto) 530 { 531 struct mbuf *m = *mp; 532 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 533 struct carp_header *ch; 534 u_int len; 535 536 CARPSTATS_INC(carps_ipackets6); 537 538 if (!V_carp_allow) { 539 m_freem(m); 540 return (IPPROTO_DONE); 541 } 542 543 /* check if received on a valid carp interface */ 544 if (m->m_pkthdr.rcvif->if_carp == NULL) { 545 CARPSTATS_INC(carps_badif); 546 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 547 __func__, m->m_pkthdr.rcvif->if_xname); 548 m_freem(m); 549 return (IPPROTO_DONE); 550 } 551 552 /* verify that the IP TTL is 255 */ 553 if (ip6->ip6_hlim != CARP_DFLTTL) { 554 CARPSTATS_INC(carps_badttl); 555 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 556 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 557 m_freem(m); 558 return (IPPROTO_DONE); 559 } 560 561 /* verify that we have a complete carp packet */ 562 len = m->m_len; 563 IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch)); 564 if (ch == NULL) { 565 CARPSTATS_INC(carps_badlen); 566 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 567 return (IPPROTO_DONE); 568 } 569 570 571 /* verify the CARP checksum */ 572 m->m_data += *offp; 573 if (in_cksum(m, sizeof(*ch))) { 574 CARPSTATS_INC(carps_badsum); 575 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 576 m->m_pkthdr.rcvif->if_xname); 577 m_freem(m); 578 return (IPPROTO_DONE); 579 } 580 m->m_data -= *offp; 581 582 carp_input_c(m, ch, AF_INET6); 583 return (IPPROTO_DONE); 584 } 585 #endif /* INET6 */ 586 587 /* 588 * This routine should not be necessary at all, but some switches 589 * (VMWare ESX vswitches) can echo our own packets back at us, 590 * and we must ignore them or they will cause us to drop out of 591 * MASTER mode. 592 * 593 * We cannot catch all cases of network loops. Instead, what we 594 * do here is catch any packet that arrives with a carp header 595 * with a VHID of 0, that comes from an address that is our own. 596 * These packets are by definition "from us" (even if they are from 597 * a misconfigured host that is pretending to be us). 598 * 599 * The VHID test is outside this mini-function. 600 */ 601 static int 602 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 603 { 604 #ifdef INET 605 struct ip *ip4; 606 struct in_addr in4; 607 #endif 608 #ifdef INET6 609 struct ip6_hdr *ip6; 610 struct in6_addr in6; 611 #endif 612 613 switch (af) { 614 #ifdef INET 615 case AF_INET: 616 ip4 = mtod(m, struct ip *); 617 in4 = ifatoia(ifa)->ia_addr.sin_addr; 618 return (in4.s_addr == ip4->ip_src.s_addr); 619 #endif 620 #ifdef INET6 621 case AF_INET6: 622 ip6 = mtod(m, struct ip6_hdr *); 623 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 624 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 625 #endif 626 default: 627 break; 628 } 629 return (0); 630 } 631 632 static void 633 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 634 { 635 struct ifnet *ifp = m->m_pkthdr.rcvif; 636 struct ifaddr *ifa, *match; 637 struct carp_softc *sc; 638 uint64_t tmp_counter; 639 struct timeval sc_tv, ch_tv; 640 int error; 641 642 /* 643 * Verify that the VHID is valid on the receiving interface. 644 * 645 * There should be just one match. If there are none 646 * the VHID is not valid and we drop the packet. If 647 * there are multiple VHID matches, take just the first 648 * one, for compatibility with previous code. While we're 649 * scanning, check for obvious loops in the network topology 650 * (these should never happen, and as noted above, we may 651 * miss real loops; this is just a double-check). 652 */ 653 IF_ADDR_RLOCK(ifp); 654 error = 0; 655 match = NULL; 656 IFNET_FOREACH_IFA(ifp, ifa) { 657 if (match == NULL && ifa->ifa_carp != NULL && 658 ifa->ifa_addr->sa_family == af && 659 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 660 match = ifa; 661 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 662 error = ELOOP; 663 } 664 ifa = error ? NULL : match; 665 if (ifa != NULL) 666 ifa_ref(ifa); 667 IF_ADDR_RUNLOCK(ifp); 668 669 if (ifa == NULL) { 670 if (error == ELOOP) { 671 CARP_DEBUG("dropping looped packet on interface %s\n", 672 ifp->if_xname); 673 CARPSTATS_INC(carps_badif); /* ??? */ 674 } else { 675 CARPSTATS_INC(carps_badvhid); 676 } 677 m_freem(m); 678 return; 679 } 680 681 /* verify the CARP version. */ 682 if (ch->carp_version != CARP_VERSION) { 683 CARPSTATS_INC(carps_badver); 684 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 685 ch->carp_version); 686 ifa_free(ifa); 687 m_freem(m); 688 return; 689 } 690 691 sc = ifa->ifa_carp; 692 CARP_LOCK(sc); 693 ifa_free(ifa); 694 695 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 696 CARPSTATS_INC(carps_badauth); 697 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 698 sc->sc_vhid, ifp->if_xname); 699 goto out; 700 } 701 702 tmp_counter = ntohl(ch->carp_counter[0]); 703 tmp_counter = tmp_counter<<32; 704 tmp_counter += ntohl(ch->carp_counter[1]); 705 706 /* XXX Replay protection goes here */ 707 708 sc->sc_init_counter = 0; 709 sc->sc_counter = tmp_counter; 710 711 sc_tv.tv_sec = sc->sc_advbase; 712 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 713 ch_tv.tv_sec = ch->carp_advbase; 714 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 715 716 switch (sc->sc_state) { 717 case INIT: 718 break; 719 case MASTER: 720 /* 721 * If we receive an advertisement from a master who's going to 722 * be more frequent than us, go into BACKUP state. 723 */ 724 if (timevalcmp(&sc_tv, &ch_tv, >) || 725 timevalcmp(&sc_tv, &ch_tv, ==)) { 726 callout_stop(&sc->sc_ad_tmo); 727 carp_set_state(sc, BACKUP, 728 "more frequent advertisement received"); 729 carp_setrun(sc, 0); 730 carp_delroute(sc); 731 } 732 break; 733 case BACKUP: 734 /* 735 * If we're pre-empting masters who advertise slower than us, 736 * and this one claims to be slower, treat him as down. 737 */ 738 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 739 carp_master_down_locked(sc, 740 "preempting a slower master"); 741 break; 742 } 743 744 /* 745 * If the master is going to advertise at such a low frequency 746 * that he's guaranteed to time out, we'd might as well just 747 * treat him as timed out now. 748 */ 749 sc_tv.tv_sec = sc->sc_advbase * 3; 750 if (timevalcmp(&sc_tv, &ch_tv, <)) { 751 carp_master_down_locked(sc, "master will time out"); 752 break; 753 } 754 755 /* 756 * Otherwise, we reset the counter and wait for the next 757 * advertisement. 758 */ 759 carp_setrun(sc, af); 760 break; 761 } 762 763 out: 764 CARP_UNLOCK(sc); 765 m_freem(m); 766 } 767 768 static int 769 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 770 { 771 struct m_tag *mtag; 772 773 if (sc->sc_init_counter) { 774 /* this could also be seconds since unix epoch */ 775 sc->sc_counter = arc4random(); 776 sc->sc_counter = sc->sc_counter << 32; 777 sc->sc_counter += arc4random(); 778 } else 779 sc->sc_counter++; 780 781 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 782 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 783 784 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 785 786 /* Tag packet for carp_output */ 787 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 788 M_NOWAIT)) == NULL) { 789 m_freem(m); 790 CARPSTATS_INC(carps_onomem); 791 return (ENOMEM); 792 } 793 bcopy(&sc, mtag + 1, sizeof(sc)); 794 m_tag_prepend(m, mtag); 795 796 return (0); 797 } 798 799 /* 800 * To avoid LORs and possible recursions this function shouldn't 801 * be called directly, but scheduled via taskqueue. 802 */ 803 static void 804 carp_send_ad_all(void *ctx __unused, int pending __unused) 805 { 806 struct carp_softc *sc; 807 808 mtx_lock(&carp_mtx); 809 LIST_FOREACH(sc, &carp_list, sc_next) 810 if (sc->sc_state == MASTER) { 811 CARP_LOCK(sc); 812 CURVNET_SET(sc->sc_carpdev->if_vnet); 813 carp_send_ad_locked(sc); 814 CURVNET_RESTORE(); 815 CARP_UNLOCK(sc); 816 } 817 mtx_unlock(&carp_mtx); 818 } 819 820 /* Send a periodic advertisement, executed in callout context. */ 821 static void 822 carp_send_ad(void *v) 823 { 824 struct carp_softc *sc = v; 825 826 CARP_LOCK_ASSERT(sc); 827 CURVNET_SET(sc->sc_carpdev->if_vnet); 828 carp_send_ad_locked(sc); 829 CURVNET_RESTORE(); 830 CARP_UNLOCK(sc); 831 } 832 833 static void 834 carp_send_ad_error(struct carp_softc *sc, int error) 835 { 836 837 if (error) { 838 if (sc->sc_sendad_errors < INT_MAX) 839 sc->sc_sendad_errors++; 840 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 841 static const char fmt[] = "send error %d on %s"; 842 char msg[sizeof(fmt) + IFNAMSIZ]; 843 844 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 845 carp_demote_adj(V_carp_senderr_adj, msg); 846 } 847 sc->sc_sendad_success = 0; 848 } else { 849 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && 850 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 851 static const char fmt[] = "send ok on %s"; 852 char msg[sizeof(fmt) + IFNAMSIZ]; 853 854 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 855 carp_demote_adj(-V_carp_senderr_adj, msg); 856 sc->sc_sendad_errors = 0; 857 } else 858 sc->sc_sendad_errors = 0; 859 } 860 } 861 862 /* 863 * Pick the best ifaddr on the given ifp for sending CARP 864 * advertisements. 865 * 866 * "Best" here is defined by ifa_preferred(). This function is much 867 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 868 * 869 * (This could be simplified to return the actual address, except that 870 * it has a different format in AF_INET and AF_INET6.) 871 */ 872 static struct ifaddr * 873 carp_best_ifa(int af, struct ifnet *ifp) 874 { 875 struct ifaddr *ifa, *best; 876 877 if (af >= AF_MAX) 878 return (NULL); 879 best = NULL; 880 IF_ADDR_RLOCK(ifp); 881 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 882 if (ifa->ifa_addr->sa_family == af && 883 (best == NULL || ifa_preferred(best, ifa))) 884 best = ifa; 885 } 886 IF_ADDR_RUNLOCK(ifp); 887 if (best != NULL) 888 ifa_ref(best); 889 return (best); 890 } 891 892 static void 893 carp_send_ad_locked(struct carp_softc *sc) 894 { 895 struct carp_header ch; 896 struct timeval tv; 897 struct ifaddr *ifa; 898 struct carp_header *ch_ptr; 899 struct mbuf *m; 900 int len, advskew; 901 902 CARP_LOCK_ASSERT(sc); 903 904 advskew = DEMOTE_ADVSKEW(sc); 905 tv.tv_sec = sc->sc_advbase; 906 tv.tv_usec = advskew * 1000000 / 256; 907 908 ch.carp_version = CARP_VERSION; 909 ch.carp_type = CARP_ADVERTISEMENT; 910 ch.carp_vhid = sc->sc_vhid; 911 ch.carp_advbase = sc->sc_advbase; 912 ch.carp_advskew = advskew; 913 ch.carp_authlen = 7; /* XXX DEFINE */ 914 ch.carp_pad1 = 0; /* must be zero */ 915 ch.carp_cksum = 0; 916 917 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 918 919 #ifdef INET 920 if (sc->sc_naddrs) { 921 struct ip *ip; 922 923 m = m_gethdr(M_NOWAIT, MT_DATA); 924 if (m == NULL) { 925 CARPSTATS_INC(carps_onomem); 926 goto resched; 927 } 928 len = sizeof(*ip) + sizeof(ch); 929 m->m_pkthdr.len = len; 930 m->m_pkthdr.rcvif = NULL; 931 m->m_len = len; 932 M_ALIGN(m, m->m_len); 933 m->m_flags |= M_MCAST; 934 ip = mtod(m, struct ip *); 935 ip->ip_v = IPVERSION; 936 ip->ip_hl = sizeof(*ip) >> 2; 937 ip->ip_tos = IPTOS_LOWDELAY; 938 ip->ip_len = htons(len); 939 ip->ip_off = htons(IP_DF); 940 ip->ip_ttl = CARP_DFLTTL; 941 ip->ip_p = IPPROTO_CARP; 942 ip->ip_sum = 0; 943 ip_fillid(ip); 944 945 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 946 if (ifa != NULL) { 947 ip->ip_src.s_addr = 948 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 949 ifa_free(ifa); 950 } else 951 ip->ip_src.s_addr = 0; 952 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 953 954 ch_ptr = (struct carp_header *)(&ip[1]); 955 bcopy(&ch, ch_ptr, sizeof(ch)); 956 if (carp_prepare_ad(m, sc, ch_ptr)) 957 goto resched; 958 959 m->m_data += sizeof(*ip); 960 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 961 m->m_data -= sizeof(*ip); 962 963 CARPSTATS_INC(carps_opackets); 964 965 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 966 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 967 } 968 #endif /* INET */ 969 #ifdef INET6 970 if (sc->sc_naddrs6) { 971 struct ip6_hdr *ip6; 972 973 m = m_gethdr(M_NOWAIT, MT_DATA); 974 if (m == NULL) { 975 CARPSTATS_INC(carps_onomem); 976 goto resched; 977 } 978 len = sizeof(*ip6) + sizeof(ch); 979 m->m_pkthdr.len = len; 980 m->m_pkthdr.rcvif = NULL; 981 m->m_len = len; 982 M_ALIGN(m, m->m_len); 983 m->m_flags |= M_MCAST; 984 ip6 = mtod(m, struct ip6_hdr *); 985 bzero(ip6, sizeof(*ip6)); 986 ip6->ip6_vfc |= IPV6_VERSION; 987 ip6->ip6_hlim = CARP_DFLTTL; 988 ip6->ip6_nxt = IPPROTO_CARP; 989 990 /* set the source address */ 991 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 992 if (ifa != NULL) { 993 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 994 sizeof(struct in6_addr)); 995 ifa_free(ifa); 996 } else 997 /* This should never happen with IPv6. */ 998 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 999 1000 /* Set the multicast destination. */ 1001 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1002 ip6->ip6_dst.s6_addr8[15] = 0x12; 1003 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1004 m_freem(m); 1005 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1006 goto resched; 1007 } 1008 1009 ch_ptr = (struct carp_header *)(&ip6[1]); 1010 bcopy(&ch, ch_ptr, sizeof(ch)); 1011 if (carp_prepare_ad(m, sc, ch_ptr)) 1012 goto resched; 1013 1014 m->m_data += sizeof(*ip6); 1015 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1016 m->m_data -= sizeof(*ip6); 1017 1018 CARPSTATS_INC(carps_opackets6); 1019 1020 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1021 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1022 } 1023 #endif /* INET6 */ 1024 1025 resched: 1026 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1027 } 1028 1029 static void 1030 carp_addroute(struct carp_softc *sc) 1031 { 1032 struct ifaddr *ifa; 1033 1034 CARP_FOREACH_IFA(sc, ifa) 1035 carp_ifa_addroute(ifa); 1036 } 1037 1038 static void 1039 carp_ifa_addroute(struct ifaddr *ifa) 1040 { 1041 1042 switch (ifa->ifa_addr->sa_family) { 1043 #ifdef INET 1044 case AF_INET: 1045 in_addprefix(ifatoia(ifa), RTF_UP); 1046 ifa_add_loopback_route(ifa, 1047 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1048 break; 1049 #endif 1050 #ifdef INET6 1051 case AF_INET6: 1052 ifa_add_loopback_route(ifa, 1053 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1054 nd6_add_ifa_lle(ifatoia6(ifa)); 1055 break; 1056 #endif 1057 } 1058 } 1059 1060 static void 1061 carp_delroute(struct carp_softc *sc) 1062 { 1063 struct ifaddr *ifa; 1064 1065 CARP_FOREACH_IFA(sc, ifa) 1066 carp_ifa_delroute(ifa); 1067 } 1068 1069 static void 1070 carp_ifa_delroute(struct ifaddr *ifa) 1071 { 1072 1073 switch (ifa->ifa_addr->sa_family) { 1074 #ifdef INET 1075 case AF_INET: 1076 ifa_del_loopback_route(ifa, 1077 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1078 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1079 break; 1080 #endif 1081 #ifdef INET6 1082 case AF_INET6: 1083 ifa_del_loopback_route(ifa, 1084 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1085 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1086 break; 1087 #endif 1088 } 1089 } 1090 1091 int 1092 carp_master(struct ifaddr *ifa) 1093 { 1094 struct carp_softc *sc = ifa->ifa_carp; 1095 1096 return (sc->sc_state == MASTER); 1097 } 1098 1099 #ifdef INET 1100 /* 1101 * Broadcast a gratuitous ARP request containing 1102 * the virtual router MAC address for each IP address 1103 * associated with the virtual router. 1104 */ 1105 static void 1106 carp_send_arp(struct carp_softc *sc) 1107 { 1108 struct ifaddr *ifa; 1109 struct in_addr addr; 1110 1111 CARP_FOREACH_IFA(sc, ifa) { 1112 if (ifa->ifa_addr->sa_family != AF_INET) 1113 continue; 1114 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1115 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1116 } 1117 } 1118 1119 int 1120 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1121 { 1122 struct carp_softc *sc = ifa->ifa_carp; 1123 1124 if (sc->sc_state == MASTER) { 1125 *enaddr = LLADDR(&sc->sc_addr); 1126 return (1); 1127 } 1128 1129 return (0); 1130 } 1131 #endif 1132 1133 #ifdef INET6 1134 static void 1135 carp_send_na(struct carp_softc *sc) 1136 { 1137 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1138 struct ifaddr *ifa; 1139 struct in6_addr *in6; 1140 1141 CARP_FOREACH_IFA(sc, ifa) { 1142 if (ifa->ifa_addr->sa_family != AF_INET6) 1143 continue; 1144 1145 in6 = IFA_IN6(ifa); 1146 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1147 ND_NA_FLAG_OVERRIDE, 1, NULL); 1148 DELAY(1000); /* XXX */ 1149 } 1150 } 1151 1152 /* 1153 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1154 * matches and is not a carp address. Returns NULL otherwise. 1155 */ 1156 struct ifaddr * 1157 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1158 { 1159 struct ifaddr *ifa; 1160 1161 ifa = NULL; 1162 IF_ADDR_RLOCK(ifp); 1163 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1164 if (ifa->ifa_addr->sa_family != AF_INET6) 1165 continue; 1166 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1167 continue; 1168 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1169 ifa = NULL; 1170 else 1171 ifa_ref(ifa); 1172 break; 1173 } 1174 IF_ADDR_RUNLOCK(ifp); 1175 1176 return (ifa); 1177 } 1178 1179 caddr_t 1180 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1181 { 1182 struct ifaddr *ifa; 1183 1184 IF_ADDR_RLOCK(ifp); 1185 IFNET_FOREACH_IFA(ifp, ifa) 1186 if (ifa->ifa_addr->sa_family == AF_INET6 && 1187 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1188 struct carp_softc *sc = ifa->ifa_carp; 1189 struct m_tag *mtag; 1190 1191 IF_ADDR_RUNLOCK(ifp); 1192 1193 mtag = m_tag_get(PACKET_TAG_CARP, 1194 sizeof(struct carp_softc *), M_NOWAIT); 1195 if (mtag == NULL) 1196 /* Better a bit than nothing. */ 1197 return (LLADDR(&sc->sc_addr)); 1198 1199 bcopy(&sc, mtag + 1, sizeof(sc)); 1200 m_tag_prepend(m, mtag); 1201 1202 return (LLADDR(&sc->sc_addr)); 1203 } 1204 IF_ADDR_RUNLOCK(ifp); 1205 1206 return (NULL); 1207 } 1208 #endif /* INET6 */ 1209 1210 int 1211 carp_forus(struct ifnet *ifp, u_char *dhost) 1212 { 1213 struct carp_softc *sc; 1214 uint8_t *ena = dhost; 1215 1216 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1217 return (0); 1218 1219 CIF_LOCK(ifp->if_carp); 1220 IFNET_FOREACH_CARP(ifp, sc) { 1221 CARP_LOCK(sc); 1222 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1223 ETHER_ADDR_LEN)) { 1224 CARP_UNLOCK(sc); 1225 CIF_UNLOCK(ifp->if_carp); 1226 return (1); 1227 } 1228 CARP_UNLOCK(sc); 1229 } 1230 CIF_UNLOCK(ifp->if_carp); 1231 1232 return (0); 1233 } 1234 1235 /* Master down timeout event, executed in callout context. */ 1236 static void 1237 carp_master_down(void *v) 1238 { 1239 struct carp_softc *sc = v; 1240 1241 CARP_LOCK_ASSERT(sc); 1242 1243 CURVNET_SET(sc->sc_carpdev->if_vnet); 1244 if (sc->sc_state == BACKUP) { 1245 carp_master_down_locked(sc, "master timed out"); 1246 } 1247 CURVNET_RESTORE(); 1248 1249 CARP_UNLOCK(sc); 1250 } 1251 1252 static void 1253 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1254 { 1255 1256 CARP_LOCK_ASSERT(sc); 1257 1258 switch (sc->sc_state) { 1259 case BACKUP: 1260 carp_set_state(sc, MASTER, reason); 1261 carp_send_ad_locked(sc); 1262 #ifdef INET 1263 carp_send_arp(sc); 1264 #endif 1265 #ifdef INET6 1266 carp_send_na(sc); 1267 #endif 1268 carp_setrun(sc, 0); 1269 carp_addroute(sc); 1270 break; 1271 case INIT: 1272 case MASTER: 1273 #ifdef INVARIANTS 1274 panic("carp: VHID %u@%s: master_down event in %s state\n", 1275 sc->sc_vhid, 1276 sc->sc_carpdev->if_xname, 1277 sc->sc_state ? "MASTER" : "INIT"); 1278 #endif 1279 break; 1280 } 1281 } 1282 1283 /* 1284 * When in backup state, af indicates whether to reset the master down timer 1285 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1286 */ 1287 static void 1288 carp_setrun(struct carp_softc *sc, sa_family_t af) 1289 { 1290 struct timeval tv; 1291 1292 CARP_LOCK_ASSERT(sc); 1293 1294 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1295 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1296 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1297 !V_carp_allow) 1298 return; 1299 1300 switch (sc->sc_state) { 1301 case INIT: 1302 carp_set_state(sc, BACKUP, "initialization complete"); 1303 carp_setrun(sc, 0); 1304 break; 1305 case BACKUP: 1306 callout_stop(&sc->sc_ad_tmo); 1307 tv.tv_sec = 3 * sc->sc_advbase; 1308 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1309 switch (af) { 1310 #ifdef INET 1311 case AF_INET: 1312 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1313 carp_master_down, sc); 1314 break; 1315 #endif 1316 #ifdef INET6 1317 case AF_INET6: 1318 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1319 carp_master_down, sc); 1320 break; 1321 #endif 1322 default: 1323 #ifdef INET 1324 if (sc->sc_naddrs) 1325 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1326 carp_master_down, sc); 1327 #endif 1328 #ifdef INET6 1329 if (sc->sc_naddrs6) 1330 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1331 carp_master_down, sc); 1332 #endif 1333 break; 1334 } 1335 break; 1336 case MASTER: 1337 tv.tv_sec = sc->sc_advbase; 1338 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1339 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1340 carp_send_ad, sc); 1341 break; 1342 } 1343 } 1344 1345 /* 1346 * Setup multicast structures. 1347 */ 1348 static int 1349 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1350 { 1351 struct ifnet *ifp = cif->cif_ifp; 1352 int error = 0; 1353 1354 switch (sa) { 1355 #ifdef INET 1356 case AF_INET: 1357 { 1358 struct ip_moptions *imo = &cif->cif_imo; 1359 struct in_addr addr; 1360 1361 if (imo->imo_membership) 1362 return (0); 1363 1364 imo->imo_membership = (struct in_multi **)malloc( 1365 (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, 1366 M_WAITOK); 1367 imo->imo_mfilters = NULL; 1368 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS; 1369 imo->imo_multicast_vif = -1; 1370 1371 addr.s_addr = htonl(INADDR_CARP_GROUP); 1372 if ((error = in_joingroup(ifp, &addr, NULL, 1373 &imo->imo_membership[0])) != 0) { 1374 free(imo->imo_membership, M_CARP); 1375 break; 1376 } 1377 imo->imo_num_memberships++; 1378 imo->imo_multicast_ifp = ifp; 1379 imo->imo_multicast_ttl = CARP_DFLTTL; 1380 imo->imo_multicast_loop = 0; 1381 break; 1382 } 1383 #endif 1384 #ifdef INET6 1385 case AF_INET6: 1386 { 1387 struct ip6_moptions *im6o = &cif->cif_im6o; 1388 struct in6_addr in6; 1389 struct in6_multi *in6m; 1390 1391 if (im6o->im6o_membership) 1392 return (0); 1393 1394 im6o->im6o_membership = (struct in6_multi **)malloc( 1395 (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, 1396 M_ZERO | M_WAITOK); 1397 im6o->im6o_mfilters = NULL; 1398 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; 1399 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1400 im6o->im6o_multicast_ifp = ifp; 1401 1402 /* Join IPv6 CARP multicast group. */ 1403 bzero(&in6, sizeof(in6)); 1404 in6.s6_addr16[0] = htons(0xff02); 1405 in6.s6_addr8[15] = 0x12; 1406 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1407 free(im6o->im6o_membership, M_CARP); 1408 break; 1409 } 1410 in6m = NULL; 1411 if ((error = in6_joingroup(ifp, &in6, NULL, &in6m, 0)) != 0) { 1412 free(im6o->im6o_membership, M_CARP); 1413 break; 1414 } 1415 im6o->im6o_membership[0] = in6m; 1416 im6o->im6o_num_memberships++; 1417 1418 /* Join solicited multicast address. */ 1419 bzero(&in6, sizeof(in6)); 1420 in6.s6_addr16[0] = htons(0xff02); 1421 in6.s6_addr32[1] = 0; 1422 in6.s6_addr32[2] = htonl(1); 1423 in6.s6_addr32[3] = 0; 1424 in6.s6_addr8[12] = 0xff; 1425 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1426 in6_leavegroup(im6o->im6o_membership[0], NULL); 1427 free(im6o->im6o_membership, M_CARP); 1428 break; 1429 } 1430 in6m = NULL; 1431 if ((error = in6_joingroup(ifp, &in6, NULL, &in6m, 0)) != 0) { 1432 in6_leavegroup(im6o->im6o_membership[0], NULL); 1433 free(im6o->im6o_membership, M_CARP); 1434 break; 1435 } 1436 im6o->im6o_membership[1] = in6m; 1437 im6o->im6o_num_memberships++; 1438 break; 1439 } 1440 #endif 1441 } 1442 1443 return (error); 1444 } 1445 1446 /* 1447 * Free multicast structures. 1448 */ 1449 static void 1450 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1451 { 1452 1453 sx_assert(&carp_sx, SA_XLOCKED); 1454 1455 switch (sa) { 1456 #ifdef INET 1457 case AF_INET: 1458 if (cif->cif_naddrs == 0) { 1459 struct ip_moptions *imo = &cif->cif_imo; 1460 1461 in_leavegroup(imo->imo_membership[0], NULL); 1462 KASSERT(imo->imo_mfilters == NULL, 1463 ("%s: imo_mfilters != NULL", __func__)); 1464 free(imo->imo_membership, M_CARP); 1465 imo->imo_membership = NULL; 1466 1467 } 1468 break; 1469 #endif 1470 #ifdef INET6 1471 case AF_INET6: 1472 if (cif->cif_naddrs6 == 0) { 1473 struct ip6_moptions *im6o = &cif->cif_im6o; 1474 1475 in6_leavegroup(im6o->im6o_membership[0], NULL); 1476 in6_leavegroup(im6o->im6o_membership[1], NULL); 1477 KASSERT(im6o->im6o_mfilters == NULL, 1478 ("%s: im6o_mfilters != NULL", __func__)); 1479 free(im6o->im6o_membership, M_CARP); 1480 im6o->im6o_membership = NULL; 1481 } 1482 break; 1483 #endif 1484 } 1485 } 1486 1487 int 1488 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1489 { 1490 struct m_tag *mtag; 1491 struct carp_softc *sc; 1492 1493 if (!sa) 1494 return (0); 1495 1496 switch (sa->sa_family) { 1497 #ifdef INET 1498 case AF_INET: 1499 break; 1500 #endif 1501 #ifdef INET6 1502 case AF_INET6: 1503 break; 1504 #endif 1505 default: 1506 return (0); 1507 } 1508 1509 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1510 if (mtag == NULL) 1511 return (0); 1512 1513 bcopy(mtag + 1, &sc, sizeof(sc)); 1514 1515 /* Set the source MAC address to the Virtual Router MAC Address. */ 1516 switch (ifp->if_type) { 1517 case IFT_ETHER: 1518 case IFT_BRIDGE: 1519 case IFT_L2VLAN: { 1520 struct ether_header *eh; 1521 1522 eh = mtod(m, struct ether_header *); 1523 eh->ether_shost[0] = 0; 1524 eh->ether_shost[1] = 0; 1525 eh->ether_shost[2] = 0x5e; 1526 eh->ether_shost[3] = 0; 1527 eh->ether_shost[4] = 1; 1528 eh->ether_shost[5] = sc->sc_vhid; 1529 } 1530 break; 1531 default: 1532 printf("%s: carp is not supported for the %d interface type\n", 1533 ifp->if_xname, ifp->if_type); 1534 return (EOPNOTSUPP); 1535 } 1536 1537 return (0); 1538 } 1539 1540 static struct carp_softc* 1541 carp_alloc(struct ifnet *ifp) 1542 { 1543 struct carp_softc *sc; 1544 struct carp_if *cif; 1545 1546 sx_assert(&carp_sx, SA_XLOCKED); 1547 1548 if ((cif = ifp->if_carp) == NULL) 1549 cif = carp_alloc_if(ifp); 1550 1551 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1552 1553 sc->sc_advbase = CARP_DFLTINTV; 1554 sc->sc_vhid = -1; /* required setting */ 1555 sc->sc_init_counter = 1; 1556 sc->sc_state = INIT; 1557 1558 sc->sc_ifasiz = sizeof(struct ifaddr *); 1559 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1560 sc->sc_carpdev = ifp; 1561 1562 CARP_LOCK_INIT(sc); 1563 #ifdef INET 1564 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1565 #endif 1566 #ifdef INET6 1567 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1568 #endif 1569 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1570 1571 CIF_LOCK(cif); 1572 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1573 CIF_UNLOCK(cif); 1574 1575 mtx_lock(&carp_mtx); 1576 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1577 mtx_unlock(&carp_mtx); 1578 1579 return (sc); 1580 } 1581 1582 static void 1583 carp_grow_ifas(struct carp_softc *sc) 1584 { 1585 struct ifaddr **new; 1586 1587 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1588 CARP_LOCK(sc); 1589 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1590 free(sc->sc_ifas, M_CARP); 1591 sc->sc_ifas = new; 1592 sc->sc_ifasiz *= 2; 1593 CARP_UNLOCK(sc); 1594 } 1595 1596 static void 1597 carp_destroy(struct carp_softc *sc) 1598 { 1599 struct ifnet *ifp = sc->sc_carpdev; 1600 struct carp_if *cif = ifp->if_carp; 1601 1602 sx_assert(&carp_sx, SA_XLOCKED); 1603 1604 if (sc->sc_suppress) 1605 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1606 CARP_UNLOCK(sc); 1607 1608 CIF_LOCK(cif); 1609 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1610 CIF_UNLOCK(cif); 1611 1612 mtx_lock(&carp_mtx); 1613 LIST_REMOVE(sc, sc_next); 1614 mtx_unlock(&carp_mtx); 1615 1616 callout_drain(&sc->sc_ad_tmo); 1617 #ifdef INET 1618 callout_drain(&sc->sc_md_tmo); 1619 #endif 1620 #ifdef INET6 1621 callout_drain(&sc->sc_md6_tmo); 1622 #endif 1623 CARP_LOCK_DESTROY(sc); 1624 1625 free(sc->sc_ifas, M_CARP); 1626 free(sc, M_CARP); 1627 } 1628 1629 static struct carp_if* 1630 carp_alloc_if(struct ifnet *ifp) 1631 { 1632 struct carp_if *cif; 1633 int error; 1634 1635 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1636 1637 if ((error = ifpromisc(ifp, 1)) != 0) 1638 printf("%s: ifpromisc(%s) failed: %d\n", 1639 __func__, ifp->if_xname, error); 1640 else 1641 cif->cif_flags |= CIF_PROMISC; 1642 1643 CIF_LOCK_INIT(cif); 1644 cif->cif_ifp = ifp; 1645 TAILQ_INIT(&cif->cif_vrs); 1646 1647 IF_ADDR_WLOCK(ifp); 1648 ifp->if_carp = cif; 1649 if_ref(ifp); 1650 IF_ADDR_WUNLOCK(ifp); 1651 1652 return (cif); 1653 } 1654 1655 static void 1656 carp_free_if(struct carp_if *cif) 1657 { 1658 struct ifnet *ifp = cif->cif_ifp; 1659 1660 CIF_LOCK_ASSERT(cif); 1661 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1662 __func__)); 1663 1664 IF_ADDR_WLOCK(ifp); 1665 ifp->if_carp = NULL; 1666 IF_ADDR_WUNLOCK(ifp); 1667 1668 CIF_LOCK_DESTROY(cif); 1669 1670 if (cif->cif_flags & CIF_PROMISC) 1671 ifpromisc(ifp, 0); 1672 if_rele(ifp); 1673 1674 free(cif, M_CARP); 1675 } 1676 1677 static void 1678 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1679 { 1680 1681 CARP_LOCK(sc); 1682 carpr->carpr_state = sc->sc_state; 1683 carpr->carpr_vhid = sc->sc_vhid; 1684 carpr->carpr_advbase = sc->sc_advbase; 1685 carpr->carpr_advskew = sc->sc_advskew; 1686 if (priv) 1687 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1688 else 1689 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1690 CARP_UNLOCK(sc); 1691 } 1692 1693 int 1694 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1695 { 1696 struct carpreq carpr; 1697 struct ifnet *ifp; 1698 struct carp_softc *sc = NULL; 1699 int error = 0, locked = 0; 1700 1701 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1702 return (error); 1703 1704 ifp = ifunit_ref(ifr->ifr_name); 1705 if (ifp == NULL) 1706 return (ENXIO); 1707 1708 switch (ifp->if_type) { 1709 case IFT_ETHER: 1710 case IFT_L2VLAN: 1711 case IFT_BRIDGE: 1712 break; 1713 default: 1714 error = EOPNOTSUPP; 1715 goto out; 1716 } 1717 1718 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1719 error = EADDRNOTAVAIL; 1720 goto out; 1721 } 1722 1723 sx_xlock(&carp_sx); 1724 switch (cmd) { 1725 case SIOCSVH: 1726 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1727 break; 1728 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1729 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1730 error = EINVAL; 1731 break; 1732 } 1733 1734 if (ifp->if_carp) { 1735 IFNET_FOREACH_CARP(ifp, sc) 1736 if (sc->sc_vhid == carpr.carpr_vhid) 1737 break; 1738 } 1739 if (sc == NULL) { 1740 sc = carp_alloc(ifp); 1741 CARP_LOCK(sc); 1742 sc->sc_vhid = carpr.carpr_vhid; 1743 LLADDR(&sc->sc_addr)[0] = 0; 1744 LLADDR(&sc->sc_addr)[1] = 0; 1745 LLADDR(&sc->sc_addr)[2] = 0x5e; 1746 LLADDR(&sc->sc_addr)[3] = 0; 1747 LLADDR(&sc->sc_addr)[4] = 1; 1748 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1749 } else 1750 CARP_LOCK(sc); 1751 locked = 1; 1752 if (carpr.carpr_advbase > 0) { 1753 if (carpr.carpr_advbase > 255 || 1754 carpr.carpr_advbase < CARP_DFLTINTV) { 1755 error = EINVAL; 1756 break; 1757 } 1758 sc->sc_advbase = carpr.carpr_advbase; 1759 } 1760 if (carpr.carpr_advskew >= 255) { 1761 error = EINVAL; 1762 break; 1763 } 1764 sc->sc_advskew = carpr.carpr_advskew; 1765 if (carpr.carpr_key[0] != '\0') { 1766 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1767 carp_hmac_prepare(sc); 1768 } 1769 if (sc->sc_state != INIT && 1770 carpr.carpr_state != sc->sc_state) { 1771 switch (carpr.carpr_state) { 1772 case BACKUP: 1773 callout_stop(&sc->sc_ad_tmo); 1774 carp_set_state(sc, BACKUP, 1775 "user requested via ifconfig"); 1776 carp_setrun(sc, 0); 1777 carp_delroute(sc); 1778 break; 1779 case MASTER: 1780 carp_master_down_locked(sc, 1781 "user requested via ifconfig"); 1782 break; 1783 default: 1784 break; 1785 } 1786 } 1787 break; 1788 1789 case SIOCGVH: 1790 { 1791 int priveleged; 1792 1793 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1794 error = EINVAL; 1795 break; 1796 } 1797 if (carpr.carpr_count < 1) { 1798 error = EMSGSIZE; 1799 break; 1800 } 1801 if (ifp->if_carp == NULL) { 1802 error = ENOENT; 1803 break; 1804 } 1805 1806 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1807 if (carpr.carpr_vhid != 0) { 1808 IFNET_FOREACH_CARP(ifp, sc) 1809 if (sc->sc_vhid == carpr.carpr_vhid) 1810 break; 1811 if (sc == NULL) { 1812 error = ENOENT; 1813 break; 1814 } 1815 carp_carprcp(&carpr, sc, priveleged); 1816 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1817 sizeof(carpr)); 1818 } else { 1819 int i, count; 1820 1821 count = 0; 1822 IFNET_FOREACH_CARP(ifp, sc) 1823 count++; 1824 1825 if (count > carpr.carpr_count) { 1826 CIF_UNLOCK(ifp->if_carp); 1827 error = EMSGSIZE; 1828 break; 1829 } 1830 1831 i = 0; 1832 IFNET_FOREACH_CARP(ifp, sc) { 1833 carp_carprcp(&carpr, sc, priveleged); 1834 carpr.carpr_count = count; 1835 error = copyout(&carpr, 1836 (caddr_t)ifr_data_get_ptr(ifr) + 1837 (i * sizeof(carpr)), sizeof(carpr)); 1838 if (error) { 1839 CIF_UNLOCK(ifp->if_carp); 1840 break; 1841 } 1842 i++; 1843 } 1844 } 1845 break; 1846 } 1847 default: 1848 error = EINVAL; 1849 } 1850 sx_xunlock(&carp_sx); 1851 1852 out: 1853 if (locked) 1854 CARP_UNLOCK(sc); 1855 if_rele(ifp); 1856 1857 return (error); 1858 } 1859 1860 static int 1861 carp_get_vhid(struct ifaddr *ifa) 1862 { 1863 1864 if (ifa == NULL || ifa->ifa_carp == NULL) 1865 return (0); 1866 1867 return (ifa->ifa_carp->sc_vhid); 1868 } 1869 1870 int 1871 carp_attach(struct ifaddr *ifa, int vhid) 1872 { 1873 struct ifnet *ifp = ifa->ifa_ifp; 1874 struct carp_if *cif = ifp->if_carp; 1875 struct carp_softc *sc; 1876 int index, error; 1877 1878 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1879 1880 switch (ifa->ifa_addr->sa_family) { 1881 #ifdef INET 1882 case AF_INET: 1883 #endif 1884 #ifdef INET6 1885 case AF_INET6: 1886 #endif 1887 break; 1888 default: 1889 return (EPROTOTYPE); 1890 } 1891 1892 sx_xlock(&carp_sx); 1893 if (ifp->if_carp == NULL) { 1894 sx_xunlock(&carp_sx); 1895 return (ENOPROTOOPT); 1896 } 1897 1898 IFNET_FOREACH_CARP(ifp, sc) 1899 if (sc->sc_vhid == vhid) 1900 break; 1901 if (sc == NULL) { 1902 sx_xunlock(&carp_sx); 1903 return (ENOENT); 1904 } 1905 1906 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1907 if (error) { 1908 CIF_FREE(cif); 1909 sx_xunlock(&carp_sx); 1910 return (error); 1911 } 1912 1913 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1914 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1915 carp_grow_ifas(sc); 1916 1917 switch (ifa->ifa_addr->sa_family) { 1918 #ifdef INET 1919 case AF_INET: 1920 cif->cif_naddrs++; 1921 sc->sc_naddrs++; 1922 break; 1923 #endif 1924 #ifdef INET6 1925 case AF_INET6: 1926 cif->cif_naddrs6++; 1927 sc->sc_naddrs6++; 1928 break; 1929 #endif 1930 } 1931 1932 ifa_ref(ifa); 1933 1934 CARP_LOCK(sc); 1935 sc->sc_ifas[index - 1] = ifa; 1936 ifa->ifa_carp = sc; 1937 carp_hmac_prepare(sc); 1938 carp_sc_state(sc); 1939 CARP_UNLOCK(sc); 1940 1941 sx_xunlock(&carp_sx); 1942 1943 return (0); 1944 } 1945 1946 void 1947 carp_detach(struct ifaddr *ifa, bool keep_cif) 1948 { 1949 struct ifnet *ifp = ifa->ifa_ifp; 1950 struct carp_if *cif = ifp->if_carp; 1951 struct carp_softc *sc = ifa->ifa_carp; 1952 int i, index; 1953 1954 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1955 1956 sx_xlock(&carp_sx); 1957 1958 CARP_LOCK(sc); 1959 /* Shift array. */ 1960 index = sc->sc_naddrs + sc->sc_naddrs6; 1961 for (i = 0; i < index; i++) 1962 if (sc->sc_ifas[i] == ifa) 1963 break; 1964 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1965 for (; i < index - 1; i++) 1966 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 1967 sc->sc_ifas[index - 1] = NULL; 1968 1969 switch (ifa->ifa_addr->sa_family) { 1970 #ifdef INET 1971 case AF_INET: 1972 cif->cif_naddrs--; 1973 sc->sc_naddrs--; 1974 break; 1975 #endif 1976 #ifdef INET6 1977 case AF_INET6: 1978 cif->cif_naddrs6--; 1979 sc->sc_naddrs6--; 1980 break; 1981 #endif 1982 } 1983 1984 carp_ifa_delroute(ifa); 1985 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 1986 1987 ifa->ifa_carp = NULL; 1988 ifa_free(ifa); 1989 1990 carp_hmac_prepare(sc); 1991 carp_sc_state(sc); 1992 1993 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 1994 carp_destroy(sc); 1995 else 1996 CARP_UNLOCK(sc); 1997 1998 if (!keep_cif) 1999 CIF_FREE(cif); 2000 2001 sx_xunlock(&carp_sx); 2002 } 2003 2004 static void 2005 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2006 { 2007 2008 CARP_LOCK_ASSERT(sc); 2009 2010 if (sc->sc_state != state) { 2011 const char *carp_states[] = { CARP_STATES }; 2012 char subsys[IFNAMSIZ+5]; 2013 2014 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2015 sc->sc_carpdev->if_xname); 2016 2017 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2018 carp_states[sc->sc_state], carp_states[state], reason); 2019 2020 sc->sc_state = state; 2021 2022 devctl_notify("CARP", subsys, carp_states[state], NULL); 2023 } 2024 } 2025 2026 static void 2027 carp_linkstate(struct ifnet *ifp) 2028 { 2029 struct carp_softc *sc; 2030 2031 CIF_LOCK(ifp->if_carp); 2032 IFNET_FOREACH_CARP(ifp, sc) { 2033 CARP_LOCK(sc); 2034 carp_sc_state(sc); 2035 CARP_UNLOCK(sc); 2036 } 2037 CIF_UNLOCK(ifp->if_carp); 2038 } 2039 2040 static void 2041 carp_sc_state(struct carp_softc *sc) 2042 { 2043 2044 CARP_LOCK_ASSERT(sc); 2045 2046 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2047 !(sc->sc_carpdev->if_flags & IFF_UP) || 2048 !V_carp_allow) { 2049 callout_stop(&sc->sc_ad_tmo); 2050 #ifdef INET 2051 callout_stop(&sc->sc_md_tmo); 2052 #endif 2053 #ifdef INET6 2054 callout_stop(&sc->sc_md6_tmo); 2055 #endif 2056 carp_set_state(sc, INIT, "hardware interface down"); 2057 carp_setrun(sc, 0); 2058 if (!sc->sc_suppress) 2059 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2060 sc->sc_suppress = 1; 2061 } else { 2062 carp_set_state(sc, INIT, "hardware interface up"); 2063 carp_setrun(sc, 0); 2064 if (sc->sc_suppress) 2065 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2066 sc->sc_suppress = 0; 2067 } 2068 } 2069 2070 static void 2071 carp_demote_adj(int adj, char *reason) 2072 { 2073 atomic_add_int(&V_carp_demotion, adj); 2074 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2075 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2076 } 2077 2078 static int 2079 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2080 { 2081 int new, error; 2082 struct carp_softc *sc; 2083 2084 new = V_carp_allow; 2085 error = sysctl_handle_int(oidp, &new, 0, req); 2086 if (error || !req->newptr) 2087 return (error); 2088 2089 if (V_carp_allow != new) { 2090 V_carp_allow = new; 2091 2092 mtx_lock(&carp_mtx); 2093 LIST_FOREACH(sc, &carp_list, sc_next) { 2094 CARP_LOCK(sc); 2095 if (curvnet == sc->sc_carpdev->if_vnet) 2096 carp_sc_state(sc); 2097 CARP_UNLOCK(sc); 2098 } 2099 mtx_unlock(&carp_mtx); 2100 } 2101 2102 return (0); 2103 } 2104 2105 static int 2106 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2107 { 2108 int new, error; 2109 2110 new = V_carp_demotion; 2111 error = sysctl_handle_int(oidp, &new, 0, req); 2112 if (error || !req->newptr) 2113 return (error); 2114 2115 carp_demote_adj(new, "sysctl"); 2116 2117 return (0); 2118 } 2119 2120 #ifdef INET 2121 extern struct domain inetdomain; 2122 static struct protosw in_carp_protosw = { 2123 .pr_type = SOCK_RAW, 2124 .pr_domain = &inetdomain, 2125 .pr_protocol = IPPROTO_CARP, 2126 .pr_flags = PR_ATOMIC|PR_ADDR, 2127 .pr_input = carp_input, 2128 .pr_output = rip_output, 2129 .pr_ctloutput = rip_ctloutput, 2130 .pr_usrreqs = &rip_usrreqs 2131 }; 2132 #endif 2133 2134 #ifdef INET6 2135 extern struct domain inet6domain; 2136 static struct protosw in6_carp_protosw = { 2137 .pr_type = SOCK_RAW, 2138 .pr_domain = &inet6domain, 2139 .pr_protocol = IPPROTO_CARP, 2140 .pr_flags = PR_ATOMIC|PR_ADDR, 2141 .pr_input = carp6_input, 2142 .pr_output = rip6_output, 2143 .pr_ctloutput = rip6_ctloutput, 2144 .pr_usrreqs = &rip6_usrreqs 2145 }; 2146 #endif 2147 2148 static void 2149 carp_mod_cleanup(void) 2150 { 2151 2152 #ifdef INET 2153 if (proto_reg[CARP_INET] == 0) { 2154 (void)ipproto_unregister(IPPROTO_CARP); 2155 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2156 proto_reg[CARP_INET] = -1; 2157 } 2158 carp_iamatch_p = NULL; 2159 #endif 2160 #ifdef INET6 2161 if (proto_reg[CARP_INET6] == 0) { 2162 (void)ip6proto_unregister(IPPROTO_CARP); 2163 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2164 proto_reg[CARP_INET6] = -1; 2165 } 2166 carp_iamatch6_p = NULL; 2167 carp_macmatch6_p = NULL; 2168 #endif 2169 carp_ioctl_p = NULL; 2170 carp_attach_p = NULL; 2171 carp_detach_p = NULL; 2172 carp_get_vhid_p = NULL; 2173 carp_linkstate_p = NULL; 2174 carp_forus_p = NULL; 2175 carp_output_p = NULL; 2176 carp_demote_adj_p = NULL; 2177 carp_master_p = NULL; 2178 mtx_unlock(&carp_mtx); 2179 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2180 mtx_destroy(&carp_mtx); 2181 sx_destroy(&carp_sx); 2182 } 2183 2184 static int 2185 carp_mod_load(void) 2186 { 2187 int err; 2188 2189 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2190 sx_init(&carp_sx, "carp_sx"); 2191 LIST_INIT(&carp_list); 2192 carp_get_vhid_p = carp_get_vhid; 2193 carp_forus_p = carp_forus; 2194 carp_output_p = carp_output; 2195 carp_linkstate_p = carp_linkstate; 2196 carp_ioctl_p = carp_ioctl; 2197 carp_attach_p = carp_attach; 2198 carp_detach_p = carp_detach; 2199 carp_demote_adj_p = carp_demote_adj; 2200 carp_master_p = carp_master; 2201 #ifdef INET6 2202 carp_iamatch6_p = carp_iamatch6; 2203 carp_macmatch6_p = carp_macmatch6; 2204 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2205 (struct protosw *)&in6_carp_protosw); 2206 if (proto_reg[CARP_INET6]) { 2207 printf("carp: error %d attaching to PF_INET6\n", 2208 proto_reg[CARP_INET6]); 2209 carp_mod_cleanup(); 2210 return (proto_reg[CARP_INET6]); 2211 } 2212 err = ip6proto_register(IPPROTO_CARP); 2213 if (err) { 2214 printf("carp: error %d registering with INET6\n", err); 2215 carp_mod_cleanup(); 2216 return (err); 2217 } 2218 #endif 2219 #ifdef INET 2220 carp_iamatch_p = carp_iamatch; 2221 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2222 if (proto_reg[CARP_INET]) { 2223 printf("carp: error %d attaching to PF_INET\n", 2224 proto_reg[CARP_INET]); 2225 carp_mod_cleanup(); 2226 return (proto_reg[CARP_INET]); 2227 } 2228 err = ipproto_register(IPPROTO_CARP); 2229 if (err) { 2230 printf("carp: error %d registering with INET\n", err); 2231 carp_mod_cleanup(); 2232 return (err); 2233 } 2234 #endif 2235 return (0); 2236 } 2237 2238 static int 2239 carp_modevent(module_t mod, int type, void *data) 2240 { 2241 switch (type) { 2242 case MOD_LOAD: 2243 return carp_mod_load(); 2244 /* NOTREACHED */ 2245 case MOD_UNLOAD: 2246 mtx_lock(&carp_mtx); 2247 if (LIST_EMPTY(&carp_list)) 2248 carp_mod_cleanup(); 2249 else { 2250 mtx_unlock(&carp_mtx); 2251 return (EBUSY); 2252 } 2253 break; 2254 2255 default: 2256 return (EINVAL); 2257 } 2258 2259 return (0); 2260 } 2261 2262 static moduledata_t carp_mod = { 2263 "carp", 2264 carp_modevent, 2265 0 2266 }; 2267 2268 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2269