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_private.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 /* 152 * Brief design of carp(4). 153 * 154 * Any carp-capable ifnet may have a list of carp softcs hanging off 155 * its ifp->if_carp pointer. Each softc represents one unique virtual 156 * host id, or vhid. The softc has a back pointer to the ifnet. All 157 * softcs are joined in a global list, which has quite limited use. 158 * 159 * Any interface address that takes part in CARP negotiation has a 160 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either 161 * AF_INET or AF_INET6 address. 162 * 163 * Although, one can get the softc's backpointer to ifnet and traverse 164 * through its ifp->if_addrhead queue to find all interface addresses 165 * involved in CARP, we keep a growable array of ifaddr pointers. This 166 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that 167 * do calls into the network stack, thus avoiding LORs. 168 * 169 * Locking: 170 * 171 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), 172 * callout-driven events and ioctl()s. 173 * 174 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. 175 * To traverse the global list we use the mutex carp_mtx. 176 * 177 * Known issues with locking: 178 * 179 * - Sending ad, we put the pointer to the softc in an mtag, and no reference 180 * counting is done on the softc. 181 * - On module unload we may race (?) with packet processing thread 182 * dereferencing our function pointers. 183 */ 184 185 /* Accept incoming CARP packets. */ 186 VNET_DEFINE_STATIC(int, carp_allow) = 1; 187 #define V_carp_allow VNET(carp_allow) 188 189 /* Set DSCP in outgoing CARP packets. */ 190 VNET_DEFINE_STATIC(int, carp_dscp) = 56; 191 #define V_carp_dscp VNET(carp_dscp) 192 193 /* Preempt slower nodes. */ 194 VNET_DEFINE_STATIC(int, carp_preempt) = 0; 195 #define V_carp_preempt VNET(carp_preempt) 196 197 /* Log level. */ 198 VNET_DEFINE_STATIC(int, carp_log) = 1; 199 #define V_carp_log VNET(carp_log) 200 201 /* Global advskew demotion. */ 202 VNET_DEFINE_STATIC(int, carp_demotion) = 0; 203 #define V_carp_demotion VNET(carp_demotion) 204 205 /* Send error demotion factor. */ 206 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW; 207 #define V_carp_senderr_adj VNET(carp_senderr_adj) 208 209 /* Iface down demotion factor. */ 210 VNET_DEFINE_STATIC(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_dscp_sysctl(SYSCTL_HANDLER_ARGS); 215 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 216 217 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 218 "CARP"); 219 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 220 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE, 221 &VNET_NAME(carp_allow), 0, carp_allow_sysctl, "I", 222 "Accept incoming CARP packets"); 223 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp, 224 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 225 0, 0, carp_dscp_sysctl, "I", 226 "DSCP value for carp packets"); 227 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 228 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 229 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 230 &VNET_NAME(carp_log), 0, "CARP log level"); 231 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 232 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 233 0, 0, carp_demote_adj_sysctl, "I", 234 "Adjust demotion factor (skew of advskew)"); 235 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 236 CTLFLAG_VNET | CTLFLAG_RW, 237 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 238 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 239 CTLFLAG_VNET | CTLFLAG_RW, 240 &VNET_NAME(carp_ifdown_adj), 0, 241 "Interface down demotion factor adjustment"); 242 243 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 244 VNET_PCPUSTAT_SYSINIT(carpstats); 245 VNET_PCPUSTAT_SYSUNINIT(carpstats); 246 247 #define CARPSTATS_ADD(name, val) \ 248 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 249 sizeof(uint64_t)], (val)) 250 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 251 252 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 253 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 254 255 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 256 NULL, MTX_DEF) 257 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 258 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 259 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 260 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 261 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 262 NULL, MTX_DEF) 263 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 264 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 265 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 266 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 267 #define CIF_FREE(cif) do { \ 268 CIF_LOCK(cif); \ 269 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 270 carp_free_if(cif); \ 271 else \ 272 CIF_UNLOCK(cif); \ 273 } while (0) 274 275 #define CARP_LOG(...) do { \ 276 if (V_carp_log > 0) \ 277 log(LOG_INFO, "carp: " __VA_ARGS__); \ 278 } while (0) 279 280 #define CARP_DEBUG(...) do { \ 281 if (V_carp_log > 1) \ 282 log(LOG_DEBUG, __VA_ARGS__); \ 283 } while (0) 284 285 #define IFNET_FOREACH_IFA(ifp, ifa) \ 286 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 287 if ((ifa)->ifa_carp != NULL) 288 289 #define CARP_FOREACH_IFA(sc, ifa) \ 290 CARP_LOCK_ASSERT(sc); \ 291 for (int _i = 0; \ 292 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 293 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 294 ++_i) 295 296 #define IFNET_FOREACH_CARP(ifp, sc) \ 297 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 298 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 299 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 300 301 #define DEMOTE_ADVSKEW(sc) \ 302 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 303 CARP_MAXSKEW : \ 304 (((sc)->sc_advskew + V_carp_demotion < 0) ? \ 305 0 : ((sc)->sc_advskew + V_carp_demotion))) 306 307 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 308 static struct carp_softc 309 *carp_alloc(struct ifnet *); 310 static void carp_destroy(struct carp_softc *); 311 static struct carp_if 312 *carp_alloc_if(struct ifnet *); 313 static void carp_free_if(struct carp_if *); 314 static void carp_set_state(struct carp_softc *, int, const char* reason); 315 static void carp_sc_state(struct carp_softc *); 316 static void carp_setrun(struct carp_softc *, sa_family_t); 317 static void carp_master_down(void *); 318 static void carp_master_down_locked(struct carp_softc *, 319 const char* reason); 320 static void carp_send_ad(void *); 321 static void carp_send_ad_locked(struct carp_softc *); 322 static void carp_addroute(struct carp_softc *); 323 static void carp_ifa_addroute(struct ifaddr *); 324 static void carp_delroute(struct carp_softc *); 325 static void carp_ifa_delroute(struct ifaddr *); 326 static void carp_send_ad_all(void *, int); 327 static void carp_demote_adj(int, char *); 328 329 static LIST_HEAD(, carp_softc) carp_list; 330 static struct mtx carp_mtx; 331 static struct sx carp_sx; 332 static struct task carp_sendall_task = 333 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 334 335 static void 336 carp_hmac_prepare(struct carp_softc *sc) 337 { 338 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 339 uint8_t vhid = sc->sc_vhid & 0xff; 340 struct ifaddr *ifa; 341 int i, found; 342 #ifdef INET 343 struct in_addr last, cur, in; 344 #endif 345 #ifdef INET6 346 struct in6_addr last6, cur6, in6; 347 #endif 348 349 CARP_LOCK_ASSERT(sc); 350 351 /* Compute ipad from key. */ 352 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 353 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 354 for (i = 0; i < sizeof(sc->sc_pad); i++) 355 sc->sc_pad[i] ^= 0x36; 356 357 /* Precompute first part of inner hash. */ 358 SHA1Init(&sc->sc_sha1); 359 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 360 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 361 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 362 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 363 #ifdef INET 364 cur.s_addr = 0; 365 do { 366 found = 0; 367 last = cur; 368 cur.s_addr = 0xffffffff; 369 CARP_FOREACH_IFA(sc, ifa) { 370 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 371 if (ifa->ifa_addr->sa_family == AF_INET && 372 ntohl(in.s_addr) > ntohl(last.s_addr) && 373 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 374 cur.s_addr = in.s_addr; 375 found++; 376 } 377 } 378 if (found) 379 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 380 } while (found); 381 #endif /* INET */ 382 #ifdef INET6 383 memset(&cur6, 0, sizeof(cur6)); 384 do { 385 found = 0; 386 last6 = cur6; 387 memset(&cur6, 0xff, sizeof(cur6)); 388 CARP_FOREACH_IFA(sc, ifa) { 389 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 390 if (IN6_IS_SCOPE_EMBED(&in6)) 391 in6.s6_addr16[1] = 0; 392 if (ifa->ifa_addr->sa_family == AF_INET6 && 393 memcmp(&in6, &last6, sizeof(in6)) > 0 && 394 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 395 cur6 = in6; 396 found++; 397 } 398 } 399 if (found) 400 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 401 } while (found); 402 #endif /* INET6 */ 403 404 /* convert ipad to opad */ 405 for (i = 0; i < sizeof(sc->sc_pad); i++) 406 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 407 } 408 409 static void 410 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 411 unsigned char md[20]) 412 { 413 SHA1_CTX sha1ctx; 414 415 CARP_LOCK_ASSERT(sc); 416 417 /* fetch first half of inner hash */ 418 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 419 420 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 421 SHA1Final(md, &sha1ctx); 422 423 /* outer hash */ 424 SHA1Init(&sha1ctx); 425 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 426 SHA1Update(&sha1ctx, md, 20); 427 SHA1Final(md, &sha1ctx); 428 } 429 430 static int 431 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 432 unsigned char md[20]) 433 { 434 unsigned char md2[20]; 435 436 CARP_LOCK_ASSERT(sc); 437 438 carp_hmac_generate(sc, counter, md2); 439 440 return (bcmp(md, md2, sizeof(md2))); 441 } 442 443 /* 444 * process input packet. 445 * we have rearranged checks order compared to the rfc, 446 * but it seems more efficient this way or not possible otherwise. 447 */ 448 #ifdef INET 449 static int 450 carp_input(struct mbuf **mp, int *offp, int proto) 451 { 452 struct mbuf *m = *mp; 453 struct ip *ip = mtod(m, struct ip *); 454 struct carp_header *ch; 455 int iplen, len; 456 457 iplen = *offp; 458 *mp = NULL; 459 460 CARPSTATS_INC(carps_ipackets); 461 462 if (!V_carp_allow) { 463 m_freem(m); 464 return (IPPROTO_DONE); 465 } 466 467 /* verify that the IP TTL is 255. */ 468 if (ip->ip_ttl != CARP_DFLTTL) { 469 CARPSTATS_INC(carps_badttl); 470 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 471 ip->ip_ttl, 472 m->m_pkthdr.rcvif->if_xname); 473 m_freem(m); 474 return (IPPROTO_DONE); 475 } 476 477 iplen = ip->ip_hl << 2; 478 479 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 480 CARPSTATS_INC(carps_badlen); 481 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 482 "on %s\n", __func__, m->m_len - sizeof(struct ip), 483 m->m_pkthdr.rcvif->if_xname); 484 m_freem(m); 485 return (IPPROTO_DONE); 486 } 487 488 if (iplen + sizeof(*ch) < m->m_len) { 489 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 490 CARPSTATS_INC(carps_hdrops); 491 CARP_DEBUG("%s: pullup failed\n", __func__); 492 return (IPPROTO_DONE); 493 } 494 ip = mtod(m, struct ip *); 495 } 496 ch = (struct carp_header *)((char *)ip + iplen); 497 498 /* 499 * verify that the received packet length is 500 * equal to the CARP header 501 */ 502 len = iplen + sizeof(*ch); 503 if (len > m->m_pkthdr.len) { 504 CARPSTATS_INC(carps_badlen); 505 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 506 m->m_pkthdr.len, 507 m->m_pkthdr.rcvif->if_xname); 508 m_freem(m); 509 return (IPPROTO_DONE); 510 } 511 512 if ((m = m_pullup(m, len)) == NULL) { 513 CARPSTATS_INC(carps_hdrops); 514 return (IPPROTO_DONE); 515 } 516 ip = mtod(m, struct ip *); 517 ch = (struct carp_header *)((char *)ip + iplen); 518 519 /* verify the CARP checksum */ 520 m->m_data += iplen; 521 if (in_cksum(m, len - iplen)) { 522 CARPSTATS_INC(carps_badsum); 523 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 524 m->m_pkthdr.rcvif->if_xname); 525 m_freem(m); 526 return (IPPROTO_DONE); 527 } 528 m->m_data -= iplen; 529 530 carp_input_c(m, ch, AF_INET); 531 return (IPPROTO_DONE); 532 } 533 #endif 534 535 #ifdef INET6 536 static int 537 carp6_input(struct mbuf **mp, int *offp, int proto) 538 { 539 struct mbuf *m = *mp; 540 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 541 struct carp_header *ch; 542 u_int len; 543 544 CARPSTATS_INC(carps_ipackets6); 545 546 if (!V_carp_allow) { 547 m_freem(m); 548 return (IPPROTO_DONE); 549 } 550 551 /* check if received on a valid carp interface */ 552 if (m->m_pkthdr.rcvif->if_carp == NULL) { 553 CARPSTATS_INC(carps_badif); 554 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 555 __func__, m->m_pkthdr.rcvif->if_xname); 556 m_freem(m); 557 return (IPPROTO_DONE); 558 } 559 560 /* verify that the IP TTL is 255 */ 561 if (ip6->ip6_hlim != CARP_DFLTTL) { 562 CARPSTATS_INC(carps_badttl); 563 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 564 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 565 m_freem(m); 566 return (IPPROTO_DONE); 567 } 568 569 /* verify that we have a complete carp packet */ 570 if (m->m_len < *offp + sizeof(*ch)) { 571 len = m->m_len; 572 m = m_pullup(m, *offp + sizeof(*ch)); 573 if (m == NULL) { 574 CARPSTATS_INC(carps_badlen); 575 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 576 return (IPPROTO_DONE); 577 } 578 } 579 ch = (struct carp_header *)(mtod(m, char *) + *offp); 580 581 /* verify the CARP checksum */ 582 m->m_data += *offp; 583 if (in_cksum(m, sizeof(*ch))) { 584 CARPSTATS_INC(carps_badsum); 585 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 586 m->m_pkthdr.rcvif->if_xname); 587 m_freem(m); 588 return (IPPROTO_DONE); 589 } 590 m->m_data -= *offp; 591 592 carp_input_c(m, ch, AF_INET6); 593 return (IPPROTO_DONE); 594 } 595 #endif /* INET6 */ 596 597 /* 598 * This routine should not be necessary at all, but some switches 599 * (VMWare ESX vswitches) can echo our own packets back at us, 600 * and we must ignore them or they will cause us to drop out of 601 * MASTER mode. 602 * 603 * We cannot catch all cases of network loops. Instead, what we 604 * do here is catch any packet that arrives with a carp header 605 * with a VHID of 0, that comes from an address that is our own. 606 * These packets are by definition "from us" (even if they are from 607 * a misconfigured host that is pretending to be us). 608 * 609 * The VHID test is outside this mini-function. 610 */ 611 static int 612 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 613 { 614 #ifdef INET 615 struct ip *ip4; 616 struct in_addr in4; 617 #endif 618 #ifdef INET6 619 struct ip6_hdr *ip6; 620 struct in6_addr in6; 621 #endif 622 623 switch (af) { 624 #ifdef INET 625 case AF_INET: 626 ip4 = mtod(m, struct ip *); 627 in4 = ifatoia(ifa)->ia_addr.sin_addr; 628 return (in4.s_addr == ip4->ip_src.s_addr); 629 #endif 630 #ifdef INET6 631 case AF_INET6: 632 ip6 = mtod(m, struct ip6_hdr *); 633 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 634 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 635 #endif 636 default: 637 break; 638 } 639 return (0); 640 } 641 642 static void 643 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 644 { 645 struct ifnet *ifp = m->m_pkthdr.rcvif; 646 struct ifaddr *ifa, *match; 647 struct carp_softc *sc; 648 uint64_t tmp_counter; 649 struct timeval sc_tv, ch_tv; 650 int error; 651 652 NET_EPOCH_ASSERT(); 653 654 /* 655 * Verify that the VHID is valid on the receiving interface. 656 * 657 * There should be just one match. If there are none 658 * the VHID is not valid and we drop the packet. If 659 * there are multiple VHID matches, take just the first 660 * one, for compatibility with previous code. While we're 661 * scanning, check for obvious loops in the network topology 662 * (these should never happen, and as noted above, we may 663 * miss real loops; this is just a double-check). 664 */ 665 error = 0; 666 match = NULL; 667 IFNET_FOREACH_IFA(ifp, ifa) { 668 if (match == NULL && ifa->ifa_carp != NULL && 669 ifa->ifa_addr->sa_family == af && 670 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 671 match = ifa; 672 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 673 error = ELOOP; 674 } 675 ifa = error ? NULL : match; 676 if (ifa != NULL) 677 ifa_ref(ifa); 678 679 if (ifa == NULL) { 680 if (error == ELOOP) { 681 CARP_DEBUG("dropping looped packet on interface %s\n", 682 ifp->if_xname); 683 CARPSTATS_INC(carps_badif); /* ??? */ 684 } else { 685 CARPSTATS_INC(carps_badvhid); 686 } 687 m_freem(m); 688 return; 689 } 690 691 /* verify the CARP version. */ 692 if (ch->carp_version != CARP_VERSION) { 693 CARPSTATS_INC(carps_badver); 694 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 695 ch->carp_version); 696 ifa_free(ifa); 697 m_freem(m); 698 return; 699 } 700 701 sc = ifa->ifa_carp; 702 CARP_LOCK(sc); 703 ifa_free(ifa); 704 705 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 706 CARPSTATS_INC(carps_badauth); 707 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 708 sc->sc_vhid, ifp->if_xname); 709 goto out; 710 } 711 712 tmp_counter = ntohl(ch->carp_counter[0]); 713 tmp_counter = tmp_counter<<32; 714 tmp_counter += ntohl(ch->carp_counter[1]); 715 716 /* XXX Replay protection goes here */ 717 718 sc->sc_init_counter = 0; 719 sc->sc_counter = tmp_counter; 720 721 sc_tv.tv_sec = sc->sc_advbase; 722 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 723 ch_tv.tv_sec = ch->carp_advbase; 724 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 725 726 switch (sc->sc_state) { 727 case INIT: 728 break; 729 case MASTER: 730 /* 731 * If we receive an advertisement from a master who's going to 732 * be more frequent than us, go into BACKUP state. 733 */ 734 if (timevalcmp(&sc_tv, &ch_tv, >) || 735 timevalcmp(&sc_tv, &ch_tv, ==)) { 736 callout_stop(&sc->sc_ad_tmo); 737 carp_set_state(sc, BACKUP, 738 "more frequent advertisement received"); 739 carp_setrun(sc, 0); 740 carp_delroute(sc); 741 } 742 break; 743 case BACKUP: 744 /* 745 * If we're pre-empting masters who advertise slower than us, 746 * and this one claims to be slower, treat him as down. 747 */ 748 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 749 carp_master_down_locked(sc, 750 "preempting a slower master"); 751 break; 752 } 753 754 /* 755 * If the master is going to advertise at such a low frequency 756 * that he's guaranteed to time out, we'd might as well just 757 * treat him as timed out now. 758 */ 759 sc_tv.tv_sec = sc->sc_advbase * 3; 760 if (timevalcmp(&sc_tv, &ch_tv, <)) { 761 carp_master_down_locked(sc, "master will time out"); 762 break; 763 } 764 765 /* 766 * Otherwise, we reset the counter and wait for the next 767 * advertisement. 768 */ 769 carp_setrun(sc, af); 770 break; 771 } 772 773 out: 774 CARP_UNLOCK(sc); 775 m_freem(m); 776 } 777 778 static int 779 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 780 { 781 struct m_tag *mtag; 782 783 if (sc->sc_init_counter) { 784 /* this could also be seconds since unix epoch */ 785 sc->sc_counter = arc4random(); 786 sc->sc_counter = sc->sc_counter << 32; 787 sc->sc_counter += arc4random(); 788 } else 789 sc->sc_counter++; 790 791 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 792 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 793 794 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 795 796 /* Tag packet for carp_output */ 797 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 798 M_NOWAIT)) == NULL) { 799 m_freem(m); 800 CARPSTATS_INC(carps_onomem); 801 return (ENOMEM); 802 } 803 bcopy(&sc, mtag + 1, sizeof(sc)); 804 m_tag_prepend(m, mtag); 805 806 return (0); 807 } 808 809 /* 810 * To avoid LORs and possible recursions this function shouldn't 811 * be called directly, but scheduled via taskqueue. 812 */ 813 static void 814 carp_send_ad_all(void *ctx __unused, int pending __unused) 815 { 816 struct carp_softc *sc; 817 struct epoch_tracker et; 818 819 NET_EPOCH_ENTER(et); 820 mtx_lock(&carp_mtx); 821 LIST_FOREACH(sc, &carp_list, sc_next) 822 if (sc->sc_state == MASTER) { 823 CARP_LOCK(sc); 824 CURVNET_SET(sc->sc_carpdev->if_vnet); 825 carp_send_ad_locked(sc); 826 CURVNET_RESTORE(); 827 CARP_UNLOCK(sc); 828 } 829 mtx_unlock(&carp_mtx); 830 NET_EPOCH_EXIT(et); 831 } 832 833 /* Send a periodic advertisement, executed in callout context. */ 834 static void 835 carp_send_ad(void *v) 836 { 837 struct carp_softc *sc = v; 838 struct epoch_tracker et; 839 840 NET_EPOCH_ENTER(et); 841 CARP_LOCK_ASSERT(sc); 842 CURVNET_SET(sc->sc_carpdev->if_vnet); 843 carp_send_ad_locked(sc); 844 CURVNET_RESTORE(); 845 CARP_UNLOCK(sc); 846 NET_EPOCH_EXIT(et); 847 } 848 849 static void 850 carp_send_ad_error(struct carp_softc *sc, int error) 851 { 852 853 /* 854 * We track errors and successfull sends with this logic: 855 * - Any error resets success counter to 0. 856 * - MAX_ERRORS triggers demotion. 857 * - MIN_SUCCESS successes resets error counter to 0. 858 * - MIN_SUCCESS reverts demotion, if it was triggered before. 859 */ 860 if (error) { 861 if (sc->sc_sendad_errors < INT_MAX) 862 sc->sc_sendad_errors++; 863 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 864 static const char fmt[] = "send error %d on %s"; 865 char msg[sizeof(fmt) + IFNAMSIZ]; 866 867 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 868 carp_demote_adj(V_carp_senderr_adj, msg); 869 } 870 sc->sc_sendad_success = 0; 871 } else if (sc->sc_sendad_errors > 0) { 872 if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 873 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) { 874 static const char fmt[] = "send ok on %s"; 875 char msg[sizeof(fmt) + IFNAMSIZ]; 876 877 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 878 carp_demote_adj(-V_carp_senderr_adj, msg); 879 } 880 sc->sc_sendad_errors = 0; 881 } 882 } 883 } 884 885 /* 886 * Pick the best ifaddr on the given ifp for sending CARP 887 * advertisements. 888 * 889 * "Best" here is defined by ifa_preferred(). This function is much 890 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 891 * 892 * (This could be simplified to return the actual address, except that 893 * it has a different format in AF_INET and AF_INET6.) 894 */ 895 static struct ifaddr * 896 carp_best_ifa(int af, struct ifnet *ifp) 897 { 898 struct ifaddr *ifa, *best; 899 900 NET_EPOCH_ASSERT(); 901 902 if (af >= AF_MAX) 903 return (NULL); 904 best = NULL; 905 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 906 if (ifa->ifa_addr->sa_family == af && 907 (best == NULL || ifa_preferred(best, ifa))) 908 best = ifa; 909 } 910 if (best != NULL) 911 ifa_ref(best); 912 return (best); 913 } 914 915 static void 916 carp_send_ad_locked(struct carp_softc *sc) 917 { 918 struct carp_header ch; 919 struct timeval tv; 920 struct ifaddr *ifa; 921 struct carp_header *ch_ptr; 922 struct mbuf *m; 923 int len, advskew; 924 925 NET_EPOCH_ASSERT(); 926 CARP_LOCK_ASSERT(sc); 927 928 advskew = DEMOTE_ADVSKEW(sc); 929 tv.tv_sec = sc->sc_advbase; 930 tv.tv_usec = advskew * 1000000 / 256; 931 932 ch.carp_version = CARP_VERSION; 933 ch.carp_type = CARP_ADVERTISEMENT; 934 ch.carp_vhid = sc->sc_vhid; 935 ch.carp_advbase = sc->sc_advbase; 936 ch.carp_advskew = advskew; 937 ch.carp_authlen = 7; /* XXX DEFINE */ 938 ch.carp_pad1 = 0; /* must be zero */ 939 ch.carp_cksum = 0; 940 941 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 942 943 #ifdef INET 944 if (sc->sc_naddrs) { 945 struct ip *ip; 946 947 m = m_gethdr(M_NOWAIT, MT_DATA); 948 if (m == NULL) { 949 CARPSTATS_INC(carps_onomem); 950 goto resched; 951 } 952 len = sizeof(*ip) + sizeof(ch); 953 m->m_pkthdr.len = len; 954 m->m_pkthdr.rcvif = NULL; 955 m->m_len = len; 956 M_ALIGN(m, m->m_len); 957 m->m_flags |= M_MCAST; 958 ip = mtod(m, struct ip *); 959 ip->ip_v = IPVERSION; 960 ip->ip_hl = sizeof(*ip) >> 2; 961 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET; 962 ip->ip_len = htons(len); 963 ip->ip_off = htons(IP_DF); 964 ip->ip_ttl = CARP_DFLTTL; 965 ip->ip_p = IPPROTO_CARP; 966 ip->ip_sum = 0; 967 ip_fillid(ip); 968 969 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 970 if (ifa != NULL) { 971 ip->ip_src.s_addr = 972 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 973 ifa_free(ifa); 974 } else 975 ip->ip_src.s_addr = 0; 976 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 977 978 ch_ptr = (struct carp_header *)(&ip[1]); 979 bcopy(&ch, ch_ptr, sizeof(ch)); 980 if (carp_prepare_ad(m, sc, ch_ptr)) 981 goto resched; 982 983 m->m_data += sizeof(*ip); 984 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 985 m->m_data -= sizeof(*ip); 986 987 CARPSTATS_INC(carps_opackets); 988 989 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 990 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 991 } 992 #endif /* INET */ 993 #ifdef INET6 994 if (sc->sc_naddrs6) { 995 struct ip6_hdr *ip6; 996 997 m = m_gethdr(M_NOWAIT, MT_DATA); 998 if (m == NULL) { 999 CARPSTATS_INC(carps_onomem); 1000 goto resched; 1001 } 1002 len = sizeof(*ip6) + sizeof(ch); 1003 m->m_pkthdr.len = len; 1004 m->m_pkthdr.rcvif = NULL; 1005 m->m_len = len; 1006 M_ALIGN(m, m->m_len); 1007 m->m_flags |= M_MCAST; 1008 ip6 = mtod(m, struct ip6_hdr *); 1009 bzero(ip6, sizeof(*ip6)); 1010 ip6->ip6_vfc |= IPV6_VERSION; 1011 /* Traffic class isn't defined in ip6 struct instead 1012 * it gets offset into flowid field */ 1013 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN + 1014 IPTOS_DSCP_OFFSET)); 1015 ip6->ip6_hlim = CARP_DFLTTL; 1016 ip6->ip6_nxt = IPPROTO_CARP; 1017 1018 /* set the source address */ 1019 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 1020 if (ifa != NULL) { 1021 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 1022 sizeof(struct in6_addr)); 1023 ifa_free(ifa); 1024 } else 1025 /* This should never happen with IPv6. */ 1026 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 1027 1028 /* Set the multicast destination. */ 1029 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1030 ip6->ip6_dst.s6_addr8[15] = 0x12; 1031 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1032 m_freem(m); 1033 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1034 goto resched; 1035 } 1036 1037 ch_ptr = (struct carp_header *)(&ip6[1]); 1038 bcopy(&ch, ch_ptr, sizeof(ch)); 1039 if (carp_prepare_ad(m, sc, ch_ptr)) 1040 goto resched; 1041 1042 m->m_data += sizeof(*ip6); 1043 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1044 m->m_data -= sizeof(*ip6); 1045 1046 CARPSTATS_INC(carps_opackets6); 1047 1048 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1049 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1050 } 1051 #endif /* INET6 */ 1052 1053 resched: 1054 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1055 } 1056 1057 static void 1058 carp_addroute(struct carp_softc *sc) 1059 { 1060 struct ifaddr *ifa; 1061 1062 CARP_FOREACH_IFA(sc, ifa) 1063 carp_ifa_addroute(ifa); 1064 } 1065 1066 static void 1067 carp_ifa_addroute(struct ifaddr *ifa) 1068 { 1069 1070 switch (ifa->ifa_addr->sa_family) { 1071 #ifdef INET 1072 case AF_INET: 1073 in_addprefix(ifatoia(ifa)); 1074 ifa_add_loopback_route(ifa, 1075 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1076 break; 1077 #endif 1078 #ifdef INET6 1079 case AF_INET6: 1080 ifa_add_loopback_route(ifa, 1081 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1082 nd6_add_ifa_lle(ifatoia6(ifa)); 1083 break; 1084 #endif 1085 } 1086 } 1087 1088 static void 1089 carp_delroute(struct carp_softc *sc) 1090 { 1091 struct ifaddr *ifa; 1092 1093 CARP_FOREACH_IFA(sc, ifa) 1094 carp_ifa_delroute(ifa); 1095 } 1096 1097 static void 1098 carp_ifa_delroute(struct ifaddr *ifa) 1099 { 1100 1101 switch (ifa->ifa_addr->sa_family) { 1102 #ifdef INET 1103 case AF_INET: 1104 ifa_del_loopback_route(ifa, 1105 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1106 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1107 break; 1108 #endif 1109 #ifdef INET6 1110 case AF_INET6: 1111 ifa_del_loopback_route(ifa, 1112 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1113 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1114 break; 1115 #endif 1116 } 1117 } 1118 1119 int 1120 carp_master(struct ifaddr *ifa) 1121 { 1122 struct carp_softc *sc = ifa->ifa_carp; 1123 1124 return (sc->sc_state == MASTER); 1125 } 1126 1127 #ifdef INET 1128 /* 1129 * Broadcast a gratuitous ARP request containing 1130 * the virtual router MAC address for each IP address 1131 * associated with the virtual router. 1132 */ 1133 static void 1134 carp_send_arp(struct carp_softc *sc) 1135 { 1136 struct ifaddr *ifa; 1137 struct in_addr addr; 1138 1139 NET_EPOCH_ASSERT(); 1140 1141 CARP_FOREACH_IFA(sc, ifa) { 1142 if (ifa->ifa_addr->sa_family != AF_INET) 1143 continue; 1144 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1145 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1146 } 1147 } 1148 1149 int 1150 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1151 { 1152 struct carp_softc *sc = ifa->ifa_carp; 1153 1154 if (sc->sc_state == MASTER) { 1155 *enaddr = LLADDR(&sc->sc_addr); 1156 return (1); 1157 } 1158 1159 return (0); 1160 } 1161 #endif 1162 1163 #ifdef INET6 1164 static void 1165 carp_send_na(struct carp_softc *sc) 1166 { 1167 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1168 struct ifaddr *ifa; 1169 struct in6_addr *in6; 1170 1171 CARP_FOREACH_IFA(sc, ifa) { 1172 if (ifa->ifa_addr->sa_family != AF_INET6) 1173 continue; 1174 1175 in6 = IFA_IN6(ifa); 1176 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1177 ND_NA_FLAG_OVERRIDE, 1, NULL); 1178 DELAY(1000); /* XXX */ 1179 } 1180 } 1181 1182 /* 1183 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1184 * matches and is not a carp address. Returns NULL otherwise. 1185 */ 1186 struct ifaddr * 1187 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1188 { 1189 struct ifaddr *ifa; 1190 1191 NET_EPOCH_ASSERT(); 1192 1193 ifa = NULL; 1194 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1195 if (ifa->ifa_addr->sa_family != AF_INET6) 1196 continue; 1197 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1198 continue; 1199 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1200 ifa = NULL; 1201 else 1202 ifa_ref(ifa); 1203 break; 1204 } 1205 1206 return (ifa); 1207 } 1208 1209 char * 1210 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1211 { 1212 struct ifaddr *ifa; 1213 1214 NET_EPOCH_ASSERT(); 1215 1216 IFNET_FOREACH_IFA(ifp, ifa) 1217 if (ifa->ifa_addr->sa_family == AF_INET6 && 1218 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1219 struct carp_softc *sc = ifa->ifa_carp; 1220 struct m_tag *mtag; 1221 1222 mtag = m_tag_get(PACKET_TAG_CARP, 1223 sizeof(struct carp_softc *), M_NOWAIT); 1224 if (mtag == NULL) 1225 /* Better a bit than nothing. */ 1226 return (LLADDR(&sc->sc_addr)); 1227 1228 bcopy(&sc, mtag + 1, sizeof(sc)); 1229 m_tag_prepend(m, mtag); 1230 1231 return (LLADDR(&sc->sc_addr)); 1232 } 1233 1234 return (NULL); 1235 } 1236 #endif /* INET6 */ 1237 1238 int 1239 carp_forus(struct ifnet *ifp, u_char *dhost) 1240 { 1241 struct carp_softc *sc; 1242 uint8_t *ena = dhost; 1243 1244 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1245 return (0); 1246 1247 CIF_LOCK(ifp->if_carp); 1248 IFNET_FOREACH_CARP(ifp, sc) { 1249 /* 1250 * CARP_LOCK() is not here, since would protect nothing, but 1251 * cause deadlock with if_bridge, calling this under its lock. 1252 */ 1253 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1254 ETHER_ADDR_LEN)) { 1255 CIF_UNLOCK(ifp->if_carp); 1256 return (1); 1257 } 1258 } 1259 CIF_UNLOCK(ifp->if_carp); 1260 1261 return (0); 1262 } 1263 1264 /* Master down timeout event, executed in callout context. */ 1265 static void 1266 carp_master_down(void *v) 1267 { 1268 struct carp_softc *sc = v; 1269 struct epoch_tracker et; 1270 1271 NET_EPOCH_ENTER(et); 1272 CARP_LOCK_ASSERT(sc); 1273 1274 CURVNET_SET(sc->sc_carpdev->if_vnet); 1275 if (sc->sc_state == BACKUP) { 1276 carp_master_down_locked(sc, "master timed out"); 1277 } 1278 CURVNET_RESTORE(); 1279 1280 CARP_UNLOCK(sc); 1281 NET_EPOCH_EXIT(et); 1282 } 1283 1284 static void 1285 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1286 { 1287 1288 NET_EPOCH_ASSERT(); 1289 CARP_LOCK_ASSERT(sc); 1290 1291 switch (sc->sc_state) { 1292 case BACKUP: 1293 carp_set_state(sc, MASTER, reason); 1294 carp_send_ad_locked(sc); 1295 #ifdef INET 1296 carp_send_arp(sc); 1297 #endif 1298 #ifdef INET6 1299 carp_send_na(sc); 1300 #endif 1301 carp_setrun(sc, 0); 1302 carp_addroute(sc); 1303 break; 1304 case INIT: 1305 case MASTER: 1306 #ifdef INVARIANTS 1307 panic("carp: VHID %u@%s: master_down event in %s state\n", 1308 sc->sc_vhid, 1309 sc->sc_carpdev->if_xname, 1310 sc->sc_state ? "MASTER" : "INIT"); 1311 #endif 1312 break; 1313 } 1314 } 1315 1316 /* 1317 * When in backup state, af indicates whether to reset the master down timer 1318 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1319 */ 1320 static void 1321 carp_setrun(struct carp_softc *sc, sa_family_t af) 1322 { 1323 struct timeval tv; 1324 1325 CARP_LOCK_ASSERT(sc); 1326 1327 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1328 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1329 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1330 !V_carp_allow) 1331 return; 1332 1333 switch (sc->sc_state) { 1334 case INIT: 1335 carp_set_state(sc, BACKUP, "initialization complete"); 1336 carp_setrun(sc, 0); 1337 break; 1338 case BACKUP: 1339 callout_stop(&sc->sc_ad_tmo); 1340 tv.tv_sec = 3 * sc->sc_advbase; 1341 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1342 switch (af) { 1343 #ifdef INET 1344 case AF_INET: 1345 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1346 carp_master_down, sc); 1347 break; 1348 #endif 1349 #ifdef INET6 1350 case AF_INET6: 1351 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1352 carp_master_down, sc); 1353 break; 1354 #endif 1355 default: 1356 #ifdef INET 1357 if (sc->sc_naddrs) 1358 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1359 carp_master_down, sc); 1360 #endif 1361 #ifdef INET6 1362 if (sc->sc_naddrs6) 1363 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1364 carp_master_down, sc); 1365 #endif 1366 break; 1367 } 1368 break; 1369 case MASTER: 1370 tv.tv_sec = sc->sc_advbase; 1371 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1372 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1373 carp_send_ad, sc); 1374 break; 1375 } 1376 } 1377 1378 /* 1379 * Setup multicast structures. 1380 */ 1381 static int 1382 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1383 { 1384 struct ifnet *ifp = cif->cif_ifp; 1385 int error = 0; 1386 1387 switch (sa) { 1388 #ifdef INET 1389 case AF_INET: 1390 { 1391 struct ip_moptions *imo = &cif->cif_imo; 1392 struct in_mfilter *imf; 1393 struct in_addr addr; 1394 1395 if (ip_mfilter_first(&imo->imo_head) != NULL) 1396 return (0); 1397 1398 imf = ip_mfilter_alloc(M_WAITOK, 0, 0); 1399 ip_mfilter_init(&imo->imo_head); 1400 imo->imo_multicast_vif = -1; 1401 1402 addr.s_addr = htonl(INADDR_CARP_GROUP); 1403 if ((error = in_joingroup(ifp, &addr, NULL, 1404 &imf->imf_inm)) != 0) { 1405 ip_mfilter_free(imf); 1406 break; 1407 } 1408 1409 ip_mfilter_insert(&imo->imo_head, imf); 1410 imo->imo_multicast_ifp = ifp; 1411 imo->imo_multicast_ttl = CARP_DFLTTL; 1412 imo->imo_multicast_loop = 0; 1413 break; 1414 } 1415 #endif 1416 #ifdef INET6 1417 case AF_INET6: 1418 { 1419 struct ip6_moptions *im6o = &cif->cif_im6o; 1420 struct in6_mfilter *im6f[2]; 1421 struct in6_addr in6; 1422 1423 if (ip6_mfilter_first(&im6o->im6o_head)) 1424 return (0); 1425 1426 im6f[0] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1427 im6f[1] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1428 1429 ip6_mfilter_init(&im6o->im6o_head); 1430 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1431 im6o->im6o_multicast_ifp = ifp; 1432 1433 /* Join IPv6 CARP multicast group. */ 1434 bzero(&in6, sizeof(in6)); 1435 in6.s6_addr16[0] = htons(0xff02); 1436 in6.s6_addr8[15] = 0x12; 1437 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1438 ip6_mfilter_free(im6f[0]); 1439 ip6_mfilter_free(im6f[1]); 1440 break; 1441 } 1442 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[0]->im6f_in6m, 0)) != 0) { 1443 ip6_mfilter_free(im6f[0]); 1444 ip6_mfilter_free(im6f[1]); 1445 break; 1446 } 1447 1448 /* Join solicited multicast address. */ 1449 bzero(&in6, sizeof(in6)); 1450 in6.s6_addr16[0] = htons(0xff02); 1451 in6.s6_addr32[1] = 0; 1452 in6.s6_addr32[2] = htonl(1); 1453 in6.s6_addr32[3] = 0; 1454 in6.s6_addr8[12] = 0xff; 1455 1456 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1457 ip6_mfilter_free(im6f[0]); 1458 ip6_mfilter_free(im6f[1]); 1459 break; 1460 } 1461 1462 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[1]->im6f_in6m, 0)) != 0) { 1463 in6_leavegroup(im6f[0]->im6f_in6m, NULL); 1464 ip6_mfilter_free(im6f[0]); 1465 ip6_mfilter_free(im6f[1]); 1466 break; 1467 } 1468 ip6_mfilter_insert(&im6o->im6o_head, im6f[0]); 1469 ip6_mfilter_insert(&im6o->im6o_head, im6f[1]); 1470 break; 1471 } 1472 #endif 1473 } 1474 1475 return (error); 1476 } 1477 1478 /* 1479 * Free multicast structures. 1480 */ 1481 static void 1482 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1483 { 1484 #ifdef INET 1485 struct ip_moptions *imo = &cif->cif_imo; 1486 struct in_mfilter *imf; 1487 #endif 1488 #ifdef INET6 1489 struct ip6_moptions *im6o = &cif->cif_im6o; 1490 struct in6_mfilter *im6f; 1491 #endif 1492 sx_assert(&carp_sx, SA_XLOCKED); 1493 1494 switch (sa) { 1495 #ifdef INET 1496 case AF_INET: 1497 if (cif->cif_naddrs != 0) 1498 break; 1499 1500 while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) { 1501 ip_mfilter_remove(&imo->imo_head, imf); 1502 in_leavegroup(imf->imf_inm, NULL); 1503 ip_mfilter_free(imf); 1504 } 1505 break; 1506 #endif 1507 #ifdef INET6 1508 case AF_INET6: 1509 if (cif->cif_naddrs6 != 0) 1510 break; 1511 1512 while ((im6f = ip6_mfilter_first(&im6o->im6o_head)) != NULL) { 1513 ip6_mfilter_remove(&im6o->im6o_head, im6f); 1514 in6_leavegroup(im6f->im6f_in6m, NULL); 1515 ip6_mfilter_free(im6f); 1516 } 1517 break; 1518 #endif 1519 } 1520 } 1521 1522 int 1523 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1524 { 1525 struct m_tag *mtag; 1526 struct carp_softc *sc; 1527 1528 if (!sa) 1529 return (0); 1530 1531 switch (sa->sa_family) { 1532 #ifdef INET 1533 case AF_INET: 1534 break; 1535 #endif 1536 #ifdef INET6 1537 case AF_INET6: 1538 break; 1539 #endif 1540 default: 1541 return (0); 1542 } 1543 1544 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1545 if (mtag == NULL) 1546 return (0); 1547 1548 bcopy(mtag + 1, &sc, sizeof(sc)); 1549 1550 /* Set the source MAC address to the Virtual Router MAC Address. */ 1551 switch (ifp->if_type) { 1552 case IFT_ETHER: 1553 case IFT_BRIDGE: 1554 case IFT_L2VLAN: { 1555 struct ether_header *eh; 1556 1557 eh = mtod(m, struct ether_header *); 1558 eh->ether_shost[0] = 0; 1559 eh->ether_shost[1] = 0; 1560 eh->ether_shost[2] = 0x5e; 1561 eh->ether_shost[3] = 0; 1562 eh->ether_shost[4] = 1; 1563 eh->ether_shost[5] = sc->sc_vhid; 1564 } 1565 break; 1566 default: 1567 printf("%s: carp is not supported for the %d interface type\n", 1568 ifp->if_xname, ifp->if_type); 1569 return (EOPNOTSUPP); 1570 } 1571 1572 return (0); 1573 } 1574 1575 static struct carp_softc* 1576 carp_alloc(struct ifnet *ifp) 1577 { 1578 struct carp_softc *sc; 1579 struct carp_if *cif; 1580 1581 sx_assert(&carp_sx, SA_XLOCKED); 1582 1583 if ((cif = ifp->if_carp) == NULL) 1584 cif = carp_alloc_if(ifp); 1585 1586 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1587 1588 sc->sc_advbase = CARP_DFLTINTV; 1589 sc->sc_vhid = -1; /* required setting */ 1590 sc->sc_init_counter = 1; 1591 sc->sc_state = INIT; 1592 1593 sc->sc_ifasiz = sizeof(struct ifaddr *); 1594 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1595 sc->sc_carpdev = ifp; 1596 1597 CARP_LOCK_INIT(sc); 1598 #ifdef INET 1599 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1600 #endif 1601 #ifdef INET6 1602 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1603 #endif 1604 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1605 1606 CIF_LOCK(cif); 1607 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1608 CIF_UNLOCK(cif); 1609 1610 mtx_lock(&carp_mtx); 1611 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1612 mtx_unlock(&carp_mtx); 1613 1614 return (sc); 1615 } 1616 1617 static void 1618 carp_grow_ifas(struct carp_softc *sc) 1619 { 1620 struct ifaddr **new; 1621 1622 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1623 CARP_LOCK(sc); 1624 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1625 free(sc->sc_ifas, M_CARP); 1626 sc->sc_ifas = new; 1627 sc->sc_ifasiz *= 2; 1628 CARP_UNLOCK(sc); 1629 } 1630 1631 static void 1632 carp_destroy(struct carp_softc *sc) 1633 { 1634 struct ifnet *ifp = sc->sc_carpdev; 1635 struct carp_if *cif = ifp->if_carp; 1636 1637 sx_assert(&carp_sx, SA_XLOCKED); 1638 1639 if (sc->sc_suppress) 1640 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1641 CARP_UNLOCK(sc); 1642 1643 CIF_LOCK(cif); 1644 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1645 CIF_UNLOCK(cif); 1646 1647 mtx_lock(&carp_mtx); 1648 LIST_REMOVE(sc, sc_next); 1649 mtx_unlock(&carp_mtx); 1650 1651 callout_drain(&sc->sc_ad_tmo); 1652 #ifdef INET 1653 callout_drain(&sc->sc_md_tmo); 1654 #endif 1655 #ifdef INET6 1656 callout_drain(&sc->sc_md6_tmo); 1657 #endif 1658 CARP_LOCK_DESTROY(sc); 1659 1660 free(sc->sc_ifas, M_CARP); 1661 free(sc, M_CARP); 1662 } 1663 1664 static struct carp_if* 1665 carp_alloc_if(struct ifnet *ifp) 1666 { 1667 struct carp_if *cif; 1668 int error; 1669 1670 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1671 1672 if ((error = ifpromisc(ifp, 1)) != 0) 1673 printf("%s: ifpromisc(%s) failed: %d\n", 1674 __func__, ifp->if_xname, error); 1675 else 1676 cif->cif_flags |= CIF_PROMISC; 1677 1678 CIF_LOCK_INIT(cif); 1679 cif->cif_ifp = ifp; 1680 TAILQ_INIT(&cif->cif_vrs); 1681 1682 IF_ADDR_WLOCK(ifp); 1683 ifp->if_carp = cif; 1684 if_ref(ifp); 1685 IF_ADDR_WUNLOCK(ifp); 1686 1687 return (cif); 1688 } 1689 1690 static void 1691 carp_free_if(struct carp_if *cif) 1692 { 1693 struct ifnet *ifp = cif->cif_ifp; 1694 1695 CIF_LOCK_ASSERT(cif); 1696 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1697 __func__)); 1698 1699 IF_ADDR_WLOCK(ifp); 1700 ifp->if_carp = NULL; 1701 IF_ADDR_WUNLOCK(ifp); 1702 1703 CIF_LOCK_DESTROY(cif); 1704 1705 if (cif->cif_flags & CIF_PROMISC) 1706 ifpromisc(ifp, 0); 1707 if_rele(ifp); 1708 1709 free(cif, M_CARP); 1710 } 1711 1712 static void 1713 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1714 { 1715 1716 CARP_LOCK(sc); 1717 carpr->carpr_state = sc->sc_state; 1718 carpr->carpr_vhid = sc->sc_vhid; 1719 carpr->carpr_advbase = sc->sc_advbase; 1720 carpr->carpr_advskew = sc->sc_advskew; 1721 if (priv) 1722 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1723 else 1724 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1725 CARP_UNLOCK(sc); 1726 } 1727 1728 int 1729 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1730 { 1731 struct carpreq carpr; 1732 struct ifnet *ifp; 1733 struct carp_softc *sc = NULL; 1734 int error = 0, locked = 0; 1735 1736 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1737 return (error); 1738 1739 ifp = ifunit_ref(ifr->ifr_name); 1740 if (ifp == NULL) 1741 return (ENXIO); 1742 1743 switch (ifp->if_type) { 1744 case IFT_ETHER: 1745 case IFT_L2VLAN: 1746 case IFT_BRIDGE: 1747 break; 1748 default: 1749 error = EOPNOTSUPP; 1750 goto out; 1751 } 1752 1753 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1754 error = EADDRNOTAVAIL; 1755 goto out; 1756 } 1757 1758 sx_xlock(&carp_sx); 1759 switch (cmd) { 1760 case SIOCSVH: 1761 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1762 break; 1763 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1764 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1765 error = EINVAL; 1766 break; 1767 } 1768 1769 if (ifp->if_carp) { 1770 IFNET_FOREACH_CARP(ifp, sc) 1771 if (sc->sc_vhid == carpr.carpr_vhid) 1772 break; 1773 } 1774 if (sc == NULL) { 1775 sc = carp_alloc(ifp); 1776 CARP_LOCK(sc); 1777 sc->sc_vhid = carpr.carpr_vhid; 1778 LLADDR(&sc->sc_addr)[0] = 0; 1779 LLADDR(&sc->sc_addr)[1] = 0; 1780 LLADDR(&sc->sc_addr)[2] = 0x5e; 1781 LLADDR(&sc->sc_addr)[3] = 0; 1782 LLADDR(&sc->sc_addr)[4] = 1; 1783 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1784 } else 1785 CARP_LOCK(sc); 1786 locked = 1; 1787 if (carpr.carpr_advbase > 0) { 1788 if (carpr.carpr_advbase > 255 || 1789 carpr.carpr_advbase < CARP_DFLTINTV) { 1790 error = EINVAL; 1791 break; 1792 } 1793 sc->sc_advbase = carpr.carpr_advbase; 1794 } 1795 if (carpr.carpr_advskew >= 255) { 1796 error = EINVAL; 1797 break; 1798 } 1799 sc->sc_advskew = carpr.carpr_advskew; 1800 if (carpr.carpr_key[0] != '\0') { 1801 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1802 carp_hmac_prepare(sc); 1803 } 1804 if (sc->sc_state != INIT && 1805 carpr.carpr_state != sc->sc_state) { 1806 switch (carpr.carpr_state) { 1807 case BACKUP: 1808 callout_stop(&sc->sc_ad_tmo); 1809 carp_set_state(sc, BACKUP, 1810 "user requested via ifconfig"); 1811 carp_setrun(sc, 0); 1812 carp_delroute(sc); 1813 break; 1814 case MASTER: 1815 carp_master_down_locked(sc, 1816 "user requested via ifconfig"); 1817 break; 1818 default: 1819 break; 1820 } 1821 } 1822 break; 1823 1824 case SIOCGVH: 1825 { 1826 int priveleged; 1827 1828 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1829 error = EINVAL; 1830 break; 1831 } 1832 if (carpr.carpr_count < 1) { 1833 error = EMSGSIZE; 1834 break; 1835 } 1836 if (ifp->if_carp == NULL) { 1837 error = ENOENT; 1838 break; 1839 } 1840 1841 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1842 if (carpr.carpr_vhid != 0) { 1843 IFNET_FOREACH_CARP(ifp, sc) 1844 if (sc->sc_vhid == carpr.carpr_vhid) 1845 break; 1846 if (sc == NULL) { 1847 error = ENOENT; 1848 break; 1849 } 1850 carp_carprcp(&carpr, sc, priveleged); 1851 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1852 sizeof(carpr)); 1853 } else { 1854 int i, count; 1855 1856 count = 0; 1857 IFNET_FOREACH_CARP(ifp, sc) 1858 count++; 1859 1860 if (count > carpr.carpr_count) { 1861 CIF_UNLOCK(ifp->if_carp); 1862 error = EMSGSIZE; 1863 break; 1864 } 1865 1866 i = 0; 1867 IFNET_FOREACH_CARP(ifp, sc) { 1868 carp_carprcp(&carpr, sc, priveleged); 1869 carpr.carpr_count = count; 1870 error = copyout(&carpr, 1871 (char *)ifr_data_get_ptr(ifr) + 1872 (i * sizeof(carpr)), sizeof(carpr)); 1873 if (error) { 1874 CIF_UNLOCK(ifp->if_carp); 1875 break; 1876 } 1877 i++; 1878 } 1879 } 1880 break; 1881 } 1882 default: 1883 error = EINVAL; 1884 } 1885 sx_xunlock(&carp_sx); 1886 1887 out: 1888 if (locked) 1889 CARP_UNLOCK(sc); 1890 if_rele(ifp); 1891 1892 return (error); 1893 } 1894 1895 static int 1896 carp_get_vhid(struct ifaddr *ifa) 1897 { 1898 1899 if (ifa == NULL || ifa->ifa_carp == NULL) 1900 return (0); 1901 1902 return (ifa->ifa_carp->sc_vhid); 1903 } 1904 1905 int 1906 carp_attach(struct ifaddr *ifa, int vhid) 1907 { 1908 struct ifnet *ifp = ifa->ifa_ifp; 1909 struct carp_if *cif = ifp->if_carp; 1910 struct carp_softc *sc; 1911 int index, error; 1912 1913 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1914 1915 switch (ifa->ifa_addr->sa_family) { 1916 #ifdef INET 1917 case AF_INET: 1918 #endif 1919 #ifdef INET6 1920 case AF_INET6: 1921 #endif 1922 break; 1923 default: 1924 return (EPROTOTYPE); 1925 } 1926 1927 sx_xlock(&carp_sx); 1928 if (ifp->if_carp == NULL) { 1929 sx_xunlock(&carp_sx); 1930 return (ENOPROTOOPT); 1931 } 1932 1933 IFNET_FOREACH_CARP(ifp, sc) 1934 if (sc->sc_vhid == vhid) 1935 break; 1936 if (sc == NULL) { 1937 sx_xunlock(&carp_sx); 1938 return (ENOENT); 1939 } 1940 1941 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1942 if (error) { 1943 CIF_FREE(cif); 1944 sx_xunlock(&carp_sx); 1945 return (error); 1946 } 1947 1948 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1949 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1950 carp_grow_ifas(sc); 1951 1952 switch (ifa->ifa_addr->sa_family) { 1953 #ifdef INET 1954 case AF_INET: 1955 cif->cif_naddrs++; 1956 sc->sc_naddrs++; 1957 break; 1958 #endif 1959 #ifdef INET6 1960 case AF_INET6: 1961 cif->cif_naddrs6++; 1962 sc->sc_naddrs6++; 1963 break; 1964 #endif 1965 } 1966 1967 ifa_ref(ifa); 1968 1969 CARP_LOCK(sc); 1970 sc->sc_ifas[index - 1] = ifa; 1971 ifa->ifa_carp = sc; 1972 carp_hmac_prepare(sc); 1973 carp_sc_state(sc); 1974 CARP_UNLOCK(sc); 1975 1976 sx_xunlock(&carp_sx); 1977 1978 return (0); 1979 } 1980 1981 void 1982 carp_detach(struct ifaddr *ifa, bool keep_cif) 1983 { 1984 struct ifnet *ifp = ifa->ifa_ifp; 1985 struct carp_if *cif = ifp->if_carp; 1986 struct carp_softc *sc = ifa->ifa_carp; 1987 int i, index; 1988 1989 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1990 1991 sx_xlock(&carp_sx); 1992 1993 CARP_LOCK(sc); 1994 /* Shift array. */ 1995 index = sc->sc_naddrs + sc->sc_naddrs6; 1996 for (i = 0; i < index; i++) 1997 if (sc->sc_ifas[i] == ifa) 1998 break; 1999 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 2000 for (; i < index - 1; i++) 2001 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 2002 sc->sc_ifas[index - 1] = NULL; 2003 2004 switch (ifa->ifa_addr->sa_family) { 2005 #ifdef INET 2006 case AF_INET: 2007 cif->cif_naddrs--; 2008 sc->sc_naddrs--; 2009 break; 2010 #endif 2011 #ifdef INET6 2012 case AF_INET6: 2013 cif->cif_naddrs6--; 2014 sc->sc_naddrs6--; 2015 break; 2016 #endif 2017 } 2018 2019 carp_ifa_delroute(ifa); 2020 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 2021 2022 ifa->ifa_carp = NULL; 2023 ifa_free(ifa); 2024 2025 carp_hmac_prepare(sc); 2026 carp_sc_state(sc); 2027 2028 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2029 carp_destroy(sc); 2030 else 2031 CARP_UNLOCK(sc); 2032 2033 if (!keep_cif) 2034 CIF_FREE(cif); 2035 2036 sx_xunlock(&carp_sx); 2037 } 2038 2039 static void 2040 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2041 { 2042 2043 CARP_LOCK_ASSERT(sc); 2044 2045 if (sc->sc_state != state) { 2046 const char *carp_states[] = { CARP_STATES }; 2047 char subsys[IFNAMSIZ+5]; 2048 2049 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2050 sc->sc_carpdev->if_xname); 2051 2052 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2053 carp_states[sc->sc_state], carp_states[state], reason); 2054 2055 sc->sc_state = state; 2056 2057 devctl_notify("CARP", subsys, carp_states[state], NULL); 2058 } 2059 } 2060 2061 static void 2062 carp_linkstate(struct ifnet *ifp) 2063 { 2064 struct carp_softc *sc; 2065 2066 CIF_LOCK(ifp->if_carp); 2067 IFNET_FOREACH_CARP(ifp, sc) { 2068 CARP_LOCK(sc); 2069 carp_sc_state(sc); 2070 CARP_UNLOCK(sc); 2071 } 2072 CIF_UNLOCK(ifp->if_carp); 2073 } 2074 2075 static void 2076 carp_sc_state(struct carp_softc *sc) 2077 { 2078 2079 CARP_LOCK_ASSERT(sc); 2080 2081 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2082 !(sc->sc_carpdev->if_flags & IFF_UP) || 2083 !V_carp_allow) { 2084 callout_stop(&sc->sc_ad_tmo); 2085 #ifdef INET 2086 callout_stop(&sc->sc_md_tmo); 2087 #endif 2088 #ifdef INET6 2089 callout_stop(&sc->sc_md6_tmo); 2090 #endif 2091 carp_set_state(sc, INIT, "hardware interface down"); 2092 carp_setrun(sc, 0); 2093 if (!sc->sc_suppress) 2094 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2095 sc->sc_suppress = 1; 2096 } else { 2097 carp_set_state(sc, INIT, "hardware interface up"); 2098 carp_setrun(sc, 0); 2099 if (sc->sc_suppress) 2100 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2101 sc->sc_suppress = 0; 2102 } 2103 } 2104 2105 static void 2106 carp_demote_adj(int adj, char *reason) 2107 { 2108 atomic_add_int(&V_carp_demotion, adj); 2109 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2110 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2111 } 2112 2113 static int 2114 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2115 { 2116 int new, error; 2117 struct carp_softc *sc; 2118 2119 new = V_carp_allow; 2120 error = sysctl_handle_int(oidp, &new, 0, req); 2121 if (error || !req->newptr) 2122 return (error); 2123 2124 if (V_carp_allow != new) { 2125 V_carp_allow = new; 2126 2127 mtx_lock(&carp_mtx); 2128 LIST_FOREACH(sc, &carp_list, sc_next) { 2129 CARP_LOCK(sc); 2130 if (curvnet == sc->sc_carpdev->if_vnet) 2131 carp_sc_state(sc); 2132 CARP_UNLOCK(sc); 2133 } 2134 mtx_unlock(&carp_mtx); 2135 } 2136 2137 return (0); 2138 } 2139 2140 static int 2141 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS) 2142 { 2143 int new, error; 2144 2145 new = V_carp_dscp; 2146 error = sysctl_handle_int(oidp, &new, 0, req); 2147 if (error || !req->newptr) 2148 return (error); 2149 2150 if (new < 0 || new > 63) 2151 return (EINVAL); 2152 2153 V_carp_dscp = new; 2154 2155 return (0); 2156 } 2157 2158 static int 2159 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2160 { 2161 int new, error; 2162 2163 new = V_carp_demotion; 2164 error = sysctl_handle_int(oidp, &new, 0, req); 2165 if (error || !req->newptr) 2166 return (error); 2167 2168 carp_demote_adj(new, "sysctl"); 2169 2170 return (0); 2171 } 2172 2173 static void 2174 carp_mod_cleanup(void) 2175 { 2176 2177 #ifdef INET 2178 (void)ipproto_unregister(IPPROTO_CARP); 2179 carp_iamatch_p = NULL; 2180 #endif 2181 #ifdef INET6 2182 (void)ip6proto_unregister(IPPROTO_CARP); 2183 carp_iamatch6_p = NULL; 2184 carp_macmatch6_p = NULL; 2185 #endif 2186 carp_ioctl_p = NULL; 2187 carp_attach_p = NULL; 2188 carp_detach_p = NULL; 2189 carp_get_vhid_p = NULL; 2190 carp_linkstate_p = NULL; 2191 carp_forus_p = NULL; 2192 carp_output_p = NULL; 2193 carp_demote_adj_p = NULL; 2194 carp_master_p = NULL; 2195 mtx_unlock(&carp_mtx); 2196 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2197 mtx_destroy(&carp_mtx); 2198 sx_destroy(&carp_sx); 2199 } 2200 2201 static void 2202 ipcarp_sysinit(void) 2203 { 2204 2205 /* Load allow as tunable so to postpone carp start after module load */ 2206 TUNABLE_INT_FETCH("net.inet.carp.allow", &V_carp_allow); 2207 } 2208 VNET_SYSINIT(ip_carp, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY, ipcarp_sysinit, NULL); 2209 2210 static int 2211 carp_mod_load(void) 2212 { 2213 int err; 2214 2215 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2216 sx_init(&carp_sx, "carp_sx"); 2217 LIST_INIT(&carp_list); 2218 carp_get_vhid_p = carp_get_vhid; 2219 carp_forus_p = carp_forus; 2220 carp_output_p = carp_output; 2221 carp_linkstate_p = carp_linkstate; 2222 carp_ioctl_p = carp_ioctl; 2223 carp_attach_p = carp_attach; 2224 carp_detach_p = carp_detach; 2225 carp_demote_adj_p = carp_demote_adj; 2226 carp_master_p = carp_master; 2227 #ifdef INET6 2228 carp_iamatch6_p = carp_iamatch6; 2229 carp_macmatch6_p = carp_macmatch6; 2230 err = ip6proto_register(IPPROTO_CARP, carp6_input, NULL); 2231 if (err) { 2232 printf("carp: error %d registering with INET6\n", err); 2233 carp_mod_cleanup(); 2234 return (err); 2235 } 2236 #endif 2237 #ifdef INET 2238 carp_iamatch_p = carp_iamatch; 2239 err = ipproto_register(IPPROTO_CARP, carp_input, NULL); 2240 if (err) { 2241 printf("carp: error %d registering with INET\n", err); 2242 carp_mod_cleanup(); 2243 return (err); 2244 } 2245 #endif 2246 return (0); 2247 } 2248 2249 static int 2250 carp_modevent(module_t mod, int type, void *data) 2251 { 2252 switch (type) { 2253 case MOD_LOAD: 2254 return carp_mod_load(); 2255 /* NOTREACHED */ 2256 case MOD_UNLOAD: 2257 mtx_lock(&carp_mtx); 2258 if (LIST_EMPTY(&carp_list)) 2259 carp_mod_cleanup(); 2260 else { 2261 mtx_unlock(&carp_mtx); 2262 return (EBUSY); 2263 } 2264 break; 2265 2266 default: 2267 return (EINVAL); 2268 } 2269 2270 return (0); 2271 } 2272 2273 static moduledata_t carp_mod = { 2274 "carp", 2275 carp_modevent, 2276 0 2277 }; 2278 2279 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2280