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/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/sockio.h> 52 #include <sys/sysctl.h> 53 #include <sys/syslog.h> 54 #include <sys/taskqueue.h> 55 #include <sys/counter.h> 56 57 #include <net/ethernet.h> 58 #include <net/if.h> 59 #include <net/if_var.h> 60 #include <net/if_dl.h> 61 #include <net/if_llatbl.h> 62 #include <net/if_types.h> 63 #include <net/route.h> 64 #include <net/vnet.h> 65 66 #if defined(INET) || defined(INET6) 67 #include <netinet/in.h> 68 #include <netinet/in_var.h> 69 #include <netinet/ip_carp.h> 70 #include <netinet/ip.h> 71 #include <machine/in_cksum.h> 72 #endif 73 #ifdef INET 74 #include <netinet/ip_var.h> 75 #include <netinet/if_ether.h> 76 #endif 77 78 #ifdef INET6 79 #include <netinet/icmp6.h> 80 #include <netinet/ip6.h> 81 #include <netinet6/in6_var.h> 82 #include <netinet6/ip6_var.h> 83 #include <netinet6/scope6_var.h> 84 #include <netinet6/nd6.h> 85 #endif 86 87 #include <crypto/sha1.h> 88 89 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses"); 90 91 struct carp_softc { 92 struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */ 93 struct ifaddr **sc_ifas; /* Our ifaddrs. */ 94 struct sockaddr_dl sc_addr; /* Our link level address. */ 95 struct callout sc_ad_tmo; /* Advertising timeout. */ 96 #ifdef INET 97 struct callout sc_md_tmo; /* Master down timeout. */ 98 #endif 99 #ifdef INET6 100 struct callout sc_md6_tmo; /* XXX: Master down timeout. */ 101 #endif 102 struct mtx sc_mtx; 103 104 int sc_vhid; 105 int sc_advskew; 106 int sc_advbase; 107 108 int sc_naddrs; 109 int sc_naddrs6; 110 int sc_ifasiz; 111 enum { INIT = 0, BACKUP, MASTER } sc_state; 112 int sc_suppress; 113 int sc_sendad_errors; 114 #define CARP_SENDAD_MAX_ERRORS 3 115 int sc_sendad_success; 116 #define CARP_SENDAD_MIN_SUCCESS 3 117 118 int sc_init_counter; 119 uint64_t sc_counter; 120 121 /* authentication */ 122 #define CARP_HMAC_PAD 64 123 unsigned char sc_key[CARP_KEY_LEN]; 124 unsigned char sc_pad[CARP_HMAC_PAD]; 125 SHA1_CTX sc_sha1; 126 127 TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */ 128 LIST_ENTRY(carp_softc) sc_next; /* On the global list. */ 129 }; 130 131 struct carp_if { 132 #ifdef INET 133 int cif_naddrs; 134 #endif 135 #ifdef INET6 136 int cif_naddrs6; 137 #endif 138 TAILQ_HEAD(, carp_softc) cif_vrs; 139 #ifdef INET 140 struct ip_moptions cif_imo; 141 #endif 142 #ifdef INET6 143 struct ip6_moptions cif_im6o; 144 #endif 145 struct ifnet *cif_ifp; 146 struct mtx cif_mtx; 147 uint32_t cif_flags; 148 #define CIF_PROMISC 0x00000001 149 }; 150 151 #define CARP_INET 0 152 #define CARP_INET6 1 153 static int proto_reg[] = {-1, -1}; 154 155 /* 156 * Brief design of carp(4). 157 * 158 * Any carp-capable ifnet may have a list of carp softcs hanging off 159 * its ifp->if_carp pointer. Each softc represents one unique virtual 160 * host id, or vhid. The softc has a back pointer to the ifnet. All 161 * softcs are joined in a global list, which has quite limited use. 162 * 163 * Any interface address that takes part in CARP negotiation has a 164 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either 165 * AF_INET or AF_INET6 address. 166 * 167 * Although, one can get the softc's backpointer to ifnet and traverse 168 * through its ifp->if_addrhead queue to find all interface addresses 169 * involved in CARP, we keep a growable array of ifaddr pointers. This 170 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that 171 * do calls into the network stack, thus avoiding LORs. 172 * 173 * Locking: 174 * 175 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), 176 * callout-driven events and ioctl()s. 177 * 178 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. 179 * To traverse the global list we use the mutex carp_mtx. 180 * 181 * Known issues with locking: 182 * 183 * - Sending ad, we put the pointer to the softc in an mtag, and no reference 184 * counting is done on the softc. 185 * - On module unload we may race (?) with packet processing thread 186 * dereferencing our function pointers. 187 */ 188 189 /* Accept incoming CARP packets. */ 190 VNET_DEFINE_STATIC(int, carp_allow) = 1; 191 #define V_carp_allow VNET(carp_allow) 192 193 /* Set DSCP in outgoing CARP packets. */ 194 VNET_DEFINE_STATIC(int, carp_dscp) = 56; 195 #define V_carp_dscp VNET(carp_dscp) 196 197 /* Preempt slower nodes. */ 198 VNET_DEFINE_STATIC(int, carp_preempt) = 0; 199 #define V_carp_preempt VNET(carp_preempt) 200 201 /* Log level. */ 202 VNET_DEFINE_STATIC(int, carp_log) = 1; 203 #define V_carp_log VNET(carp_log) 204 205 /* Global advskew demotion. */ 206 VNET_DEFINE_STATIC(int, carp_demotion) = 0; 207 #define V_carp_demotion VNET(carp_demotion) 208 209 /* Send error demotion factor. */ 210 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW; 211 #define V_carp_senderr_adj VNET(carp_senderr_adj) 212 213 /* Iface down demotion factor. */ 214 VNET_DEFINE_STATIC(int, carp_ifdown_adj) = CARP_MAXSKEW; 215 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 216 217 static int carp_allow_sysctl(SYSCTL_HANDLER_ARGS); 218 static int carp_dscp_sysctl(SYSCTL_HANDLER_ARGS); 219 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 220 221 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 222 "CARP"); 223 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 224 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 225 0, 0, carp_allow_sysctl, "I", 226 "Accept incoming CARP packets"); 227 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp, 228 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 229 0, 0, carp_dscp_sysctl, "I", 230 "DSCP value for carp packets"); 231 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 232 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 233 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 234 &VNET_NAME(carp_log), 0, "CARP log level"); 235 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 236 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 237 0, 0, carp_demote_adj_sysctl, "I", 238 "Adjust demotion factor (skew of advskew)"); 239 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 240 CTLFLAG_VNET | CTLFLAG_RW, 241 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 242 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 243 CTLFLAG_VNET | CTLFLAG_RW, 244 &VNET_NAME(carp_ifdown_adj), 0, 245 "Interface down demotion factor adjustment"); 246 247 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 248 VNET_PCPUSTAT_SYSINIT(carpstats); 249 VNET_PCPUSTAT_SYSUNINIT(carpstats); 250 251 #define CARPSTATS_ADD(name, val) \ 252 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 253 sizeof(uint64_t)], (val)) 254 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 255 256 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 257 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 258 259 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 260 NULL, MTX_DEF) 261 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 262 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 263 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 264 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 265 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 266 NULL, MTX_DEF) 267 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 268 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 269 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 270 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 271 #define CIF_FREE(cif) do { \ 272 CIF_LOCK(cif); \ 273 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 274 carp_free_if(cif); \ 275 else \ 276 CIF_UNLOCK(cif); \ 277 } while (0) 278 279 #define CARP_LOG(...) do { \ 280 if (V_carp_log > 0) \ 281 log(LOG_INFO, "carp: " __VA_ARGS__); \ 282 } while (0) 283 284 #define CARP_DEBUG(...) do { \ 285 if (V_carp_log > 1) \ 286 log(LOG_DEBUG, __VA_ARGS__); \ 287 } while (0) 288 289 #define IFNET_FOREACH_IFA(ifp, ifa) \ 290 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 291 if ((ifa)->ifa_carp != NULL) 292 293 #define CARP_FOREACH_IFA(sc, ifa) \ 294 CARP_LOCK_ASSERT(sc); \ 295 for (int _i = 0; \ 296 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 297 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 298 ++_i) 299 300 #define IFNET_FOREACH_CARP(ifp, sc) \ 301 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 302 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 303 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 304 305 #define DEMOTE_ADVSKEW(sc) \ 306 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 307 CARP_MAXSKEW : \ 308 (((sc)->sc_advskew + V_carp_demotion < 0) ? \ 309 0 : ((sc)->sc_advskew + V_carp_demotion))) 310 311 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 312 static struct carp_softc 313 *carp_alloc(struct ifnet *); 314 static void carp_destroy(struct carp_softc *); 315 static struct carp_if 316 *carp_alloc_if(struct ifnet *); 317 static void carp_free_if(struct carp_if *); 318 static void carp_set_state(struct carp_softc *, int, const char* reason); 319 static void carp_sc_state(struct carp_softc *); 320 static void carp_setrun(struct carp_softc *, sa_family_t); 321 static void carp_master_down(void *); 322 static void carp_master_down_locked(struct carp_softc *, 323 const char* reason); 324 static void carp_send_ad(void *); 325 static void carp_send_ad_locked(struct carp_softc *); 326 static void carp_addroute(struct carp_softc *); 327 static void carp_ifa_addroute(struct ifaddr *); 328 static void carp_delroute(struct carp_softc *); 329 static void carp_ifa_delroute(struct ifaddr *); 330 static void carp_send_ad_all(void *, int); 331 static void carp_demote_adj(int, char *); 332 333 static LIST_HEAD(, carp_softc) carp_list; 334 static struct mtx carp_mtx; 335 static struct sx carp_sx; 336 static struct task carp_sendall_task = 337 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 338 339 static void 340 carp_hmac_prepare(struct carp_softc *sc) 341 { 342 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 343 uint8_t vhid = sc->sc_vhid & 0xff; 344 struct ifaddr *ifa; 345 int i, found; 346 #ifdef INET 347 struct in_addr last, cur, in; 348 #endif 349 #ifdef INET6 350 struct in6_addr last6, cur6, in6; 351 #endif 352 353 CARP_LOCK_ASSERT(sc); 354 355 /* Compute ipad from key. */ 356 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 357 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 358 for (i = 0; i < sizeof(sc->sc_pad); i++) 359 sc->sc_pad[i] ^= 0x36; 360 361 /* Precompute first part of inner hash. */ 362 SHA1Init(&sc->sc_sha1); 363 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 364 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 365 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 366 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 367 #ifdef INET 368 cur.s_addr = 0; 369 do { 370 found = 0; 371 last = cur; 372 cur.s_addr = 0xffffffff; 373 CARP_FOREACH_IFA(sc, ifa) { 374 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 375 if (ifa->ifa_addr->sa_family == AF_INET && 376 ntohl(in.s_addr) > ntohl(last.s_addr) && 377 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 378 cur.s_addr = in.s_addr; 379 found++; 380 } 381 } 382 if (found) 383 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 384 } while (found); 385 #endif /* INET */ 386 #ifdef INET6 387 memset(&cur6, 0, sizeof(cur6)); 388 do { 389 found = 0; 390 last6 = cur6; 391 memset(&cur6, 0xff, sizeof(cur6)); 392 CARP_FOREACH_IFA(sc, ifa) { 393 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 394 if (IN6_IS_SCOPE_EMBED(&in6)) 395 in6.s6_addr16[1] = 0; 396 if (ifa->ifa_addr->sa_family == AF_INET6 && 397 memcmp(&in6, &last6, sizeof(in6)) > 0 && 398 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 399 cur6 = in6; 400 found++; 401 } 402 } 403 if (found) 404 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 405 } while (found); 406 #endif /* INET6 */ 407 408 /* convert ipad to opad */ 409 for (i = 0; i < sizeof(sc->sc_pad); i++) 410 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 411 } 412 413 static void 414 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 415 unsigned char md[20]) 416 { 417 SHA1_CTX sha1ctx; 418 419 CARP_LOCK_ASSERT(sc); 420 421 /* fetch first half of inner hash */ 422 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 423 424 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 425 SHA1Final(md, &sha1ctx); 426 427 /* outer hash */ 428 SHA1Init(&sha1ctx); 429 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 430 SHA1Update(&sha1ctx, md, 20); 431 SHA1Final(md, &sha1ctx); 432 } 433 434 static int 435 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 436 unsigned char md[20]) 437 { 438 unsigned char md2[20]; 439 440 CARP_LOCK_ASSERT(sc); 441 442 carp_hmac_generate(sc, counter, md2); 443 444 return (bcmp(md, md2, sizeof(md2))); 445 } 446 447 /* 448 * process input packet. 449 * we have rearranged checks order compared to the rfc, 450 * but it seems more efficient this way or not possible otherwise. 451 */ 452 #ifdef INET 453 int 454 carp_input(struct mbuf **mp, int *offp, int proto) 455 { 456 struct mbuf *m = *mp; 457 struct ip *ip = mtod(m, struct ip *); 458 struct carp_header *ch; 459 int iplen, len; 460 461 iplen = *offp; 462 *mp = NULL; 463 464 CARPSTATS_INC(carps_ipackets); 465 466 if (!V_carp_allow) { 467 m_freem(m); 468 return (IPPROTO_DONE); 469 } 470 471 /* verify that the IP TTL is 255. */ 472 if (ip->ip_ttl != CARP_DFLTTL) { 473 CARPSTATS_INC(carps_badttl); 474 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 475 ip->ip_ttl, 476 m->m_pkthdr.rcvif->if_xname); 477 m_freem(m); 478 return (IPPROTO_DONE); 479 } 480 481 iplen = ip->ip_hl << 2; 482 483 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 484 CARPSTATS_INC(carps_badlen); 485 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 486 "on %s\n", __func__, m->m_len - sizeof(struct ip), 487 m->m_pkthdr.rcvif->if_xname); 488 m_freem(m); 489 return (IPPROTO_DONE); 490 } 491 492 if (iplen + sizeof(*ch) < m->m_len) { 493 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 494 CARPSTATS_INC(carps_hdrops); 495 CARP_DEBUG("%s: pullup failed\n", __func__); 496 return (IPPROTO_DONE); 497 } 498 ip = mtod(m, struct ip *); 499 } 500 ch = (struct carp_header *)((char *)ip + iplen); 501 502 /* 503 * verify that the received packet length is 504 * equal to the CARP header 505 */ 506 len = iplen + sizeof(*ch); 507 if (len > m->m_pkthdr.len) { 508 CARPSTATS_INC(carps_badlen); 509 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 510 m->m_pkthdr.len, 511 m->m_pkthdr.rcvif->if_xname); 512 m_freem(m); 513 return (IPPROTO_DONE); 514 } 515 516 if ((m = m_pullup(m, len)) == NULL) { 517 CARPSTATS_INC(carps_hdrops); 518 return (IPPROTO_DONE); 519 } 520 ip = mtod(m, struct ip *); 521 ch = (struct carp_header *)((char *)ip + iplen); 522 523 /* verify the CARP checksum */ 524 m->m_data += iplen; 525 if (in_cksum(m, len - iplen)) { 526 CARPSTATS_INC(carps_badsum); 527 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 528 m->m_pkthdr.rcvif->if_xname); 529 m_freem(m); 530 return (IPPROTO_DONE); 531 } 532 m->m_data -= iplen; 533 534 carp_input_c(m, ch, AF_INET); 535 return (IPPROTO_DONE); 536 } 537 #endif 538 539 #ifdef INET6 540 int 541 carp6_input(struct mbuf **mp, int *offp, int proto) 542 { 543 struct mbuf *m = *mp; 544 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 545 struct carp_header *ch; 546 u_int len; 547 548 CARPSTATS_INC(carps_ipackets6); 549 550 if (!V_carp_allow) { 551 m_freem(m); 552 return (IPPROTO_DONE); 553 } 554 555 /* check if received on a valid carp interface */ 556 if (m->m_pkthdr.rcvif->if_carp == NULL) { 557 CARPSTATS_INC(carps_badif); 558 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 559 __func__, m->m_pkthdr.rcvif->if_xname); 560 m_freem(m); 561 return (IPPROTO_DONE); 562 } 563 564 /* verify that the IP TTL is 255 */ 565 if (ip6->ip6_hlim != CARP_DFLTTL) { 566 CARPSTATS_INC(carps_badttl); 567 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 568 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 569 m_freem(m); 570 return (IPPROTO_DONE); 571 } 572 573 /* verify that we have a complete carp packet */ 574 if (m->m_len < *offp + sizeof(*ch)) { 575 len = m->m_len; 576 m = m_pullup(m, *offp + sizeof(*ch)); 577 if (m == NULL) { 578 CARPSTATS_INC(carps_badlen); 579 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 580 return (IPPROTO_DONE); 581 } 582 } 583 ch = (struct carp_header *)(mtod(m, char *) + *offp); 584 585 /* verify the CARP checksum */ 586 m->m_data += *offp; 587 if (in_cksum(m, sizeof(*ch))) { 588 CARPSTATS_INC(carps_badsum); 589 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 590 m->m_pkthdr.rcvif->if_xname); 591 m_freem(m); 592 return (IPPROTO_DONE); 593 } 594 m->m_data -= *offp; 595 596 carp_input_c(m, ch, AF_INET6); 597 return (IPPROTO_DONE); 598 } 599 #endif /* INET6 */ 600 601 /* 602 * This routine should not be necessary at all, but some switches 603 * (VMWare ESX vswitches) can echo our own packets back at us, 604 * and we must ignore them or they will cause us to drop out of 605 * MASTER mode. 606 * 607 * We cannot catch all cases of network loops. Instead, what we 608 * do here is catch any packet that arrives with a carp header 609 * with a VHID of 0, that comes from an address that is our own. 610 * These packets are by definition "from us" (even if they are from 611 * a misconfigured host that is pretending to be us). 612 * 613 * The VHID test is outside this mini-function. 614 */ 615 static int 616 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 617 { 618 #ifdef INET 619 struct ip *ip4; 620 struct in_addr in4; 621 #endif 622 #ifdef INET6 623 struct ip6_hdr *ip6; 624 struct in6_addr in6; 625 #endif 626 627 switch (af) { 628 #ifdef INET 629 case AF_INET: 630 ip4 = mtod(m, struct ip *); 631 in4 = ifatoia(ifa)->ia_addr.sin_addr; 632 return (in4.s_addr == ip4->ip_src.s_addr); 633 #endif 634 #ifdef INET6 635 case AF_INET6: 636 ip6 = mtod(m, struct ip6_hdr *); 637 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 638 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 639 #endif 640 default: 641 break; 642 } 643 return (0); 644 } 645 646 static void 647 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 648 { 649 struct ifnet *ifp = m->m_pkthdr.rcvif; 650 struct ifaddr *ifa, *match; 651 struct carp_softc *sc; 652 uint64_t tmp_counter; 653 struct timeval sc_tv, ch_tv; 654 int error; 655 656 NET_EPOCH_ASSERT(); 657 658 /* 659 * Verify that the VHID is valid on the receiving interface. 660 * 661 * There should be just one match. If there are none 662 * the VHID is not valid and we drop the packet. If 663 * there are multiple VHID matches, take just the first 664 * one, for compatibility with previous code. While we're 665 * scanning, check for obvious loops in the network topology 666 * (these should never happen, and as noted above, we may 667 * miss real loops; this is just a double-check). 668 */ 669 error = 0; 670 match = NULL; 671 IFNET_FOREACH_IFA(ifp, ifa) { 672 if (match == NULL && ifa->ifa_carp != NULL && 673 ifa->ifa_addr->sa_family == af && 674 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 675 match = ifa; 676 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 677 error = ELOOP; 678 } 679 ifa = error ? NULL : match; 680 if (ifa != NULL) 681 ifa_ref(ifa); 682 683 if (ifa == NULL) { 684 if (error == ELOOP) { 685 CARP_DEBUG("dropping looped packet on interface %s\n", 686 ifp->if_xname); 687 CARPSTATS_INC(carps_badif); /* ??? */ 688 } else { 689 CARPSTATS_INC(carps_badvhid); 690 } 691 m_freem(m); 692 return; 693 } 694 695 /* verify the CARP version. */ 696 if (ch->carp_version != CARP_VERSION) { 697 CARPSTATS_INC(carps_badver); 698 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 699 ch->carp_version); 700 ifa_free(ifa); 701 m_freem(m); 702 return; 703 } 704 705 sc = ifa->ifa_carp; 706 CARP_LOCK(sc); 707 ifa_free(ifa); 708 709 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 710 CARPSTATS_INC(carps_badauth); 711 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 712 sc->sc_vhid, ifp->if_xname); 713 goto out; 714 } 715 716 tmp_counter = ntohl(ch->carp_counter[0]); 717 tmp_counter = tmp_counter<<32; 718 tmp_counter += ntohl(ch->carp_counter[1]); 719 720 /* XXX Replay protection goes here */ 721 722 sc->sc_init_counter = 0; 723 sc->sc_counter = tmp_counter; 724 725 sc_tv.tv_sec = sc->sc_advbase; 726 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 727 ch_tv.tv_sec = ch->carp_advbase; 728 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 729 730 switch (sc->sc_state) { 731 case INIT: 732 break; 733 case MASTER: 734 /* 735 * If we receive an advertisement from a master who's going to 736 * be more frequent than us, go into BACKUP state. 737 */ 738 if (timevalcmp(&sc_tv, &ch_tv, >) || 739 timevalcmp(&sc_tv, &ch_tv, ==)) { 740 callout_stop(&sc->sc_ad_tmo); 741 carp_set_state(sc, BACKUP, 742 "more frequent advertisement received"); 743 carp_setrun(sc, 0); 744 carp_delroute(sc); 745 } 746 break; 747 case BACKUP: 748 /* 749 * If we're pre-empting masters who advertise slower than us, 750 * and this one claims to be slower, treat him as down. 751 */ 752 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 753 carp_master_down_locked(sc, 754 "preempting a slower master"); 755 break; 756 } 757 758 /* 759 * If the master is going to advertise at such a low frequency 760 * that he's guaranteed to time out, we'd might as well just 761 * treat him as timed out now. 762 */ 763 sc_tv.tv_sec = sc->sc_advbase * 3; 764 if (timevalcmp(&sc_tv, &ch_tv, <)) { 765 carp_master_down_locked(sc, "master will time out"); 766 break; 767 } 768 769 /* 770 * Otherwise, we reset the counter and wait for the next 771 * advertisement. 772 */ 773 carp_setrun(sc, af); 774 break; 775 } 776 777 out: 778 CARP_UNLOCK(sc); 779 m_freem(m); 780 } 781 782 static int 783 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 784 { 785 struct m_tag *mtag; 786 787 if (sc->sc_init_counter) { 788 /* this could also be seconds since unix epoch */ 789 sc->sc_counter = arc4random(); 790 sc->sc_counter = sc->sc_counter << 32; 791 sc->sc_counter += arc4random(); 792 } else 793 sc->sc_counter++; 794 795 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 796 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 797 798 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 799 800 /* Tag packet for carp_output */ 801 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 802 M_NOWAIT)) == NULL) { 803 m_freem(m); 804 CARPSTATS_INC(carps_onomem); 805 return (ENOMEM); 806 } 807 bcopy(&sc, mtag + 1, sizeof(sc)); 808 m_tag_prepend(m, mtag); 809 810 return (0); 811 } 812 813 /* 814 * To avoid LORs and possible recursions this function shouldn't 815 * be called directly, but scheduled via taskqueue. 816 */ 817 static void 818 carp_send_ad_all(void *ctx __unused, int pending __unused) 819 { 820 struct carp_softc *sc; 821 struct epoch_tracker et; 822 823 NET_EPOCH_ENTER(et); 824 mtx_lock(&carp_mtx); 825 LIST_FOREACH(sc, &carp_list, sc_next) 826 if (sc->sc_state == MASTER) { 827 CARP_LOCK(sc); 828 CURVNET_SET(sc->sc_carpdev->if_vnet); 829 carp_send_ad_locked(sc); 830 CURVNET_RESTORE(); 831 CARP_UNLOCK(sc); 832 } 833 mtx_unlock(&carp_mtx); 834 NET_EPOCH_EXIT(et); 835 } 836 837 /* Send a periodic advertisement, executed in callout context. */ 838 static void 839 carp_send_ad(void *v) 840 { 841 struct carp_softc *sc = v; 842 struct epoch_tracker et; 843 844 NET_EPOCH_ENTER(et); 845 CARP_LOCK_ASSERT(sc); 846 CURVNET_SET(sc->sc_carpdev->if_vnet); 847 carp_send_ad_locked(sc); 848 CURVNET_RESTORE(); 849 CARP_UNLOCK(sc); 850 NET_EPOCH_EXIT(et); 851 } 852 853 static void 854 carp_send_ad_error(struct carp_softc *sc, int error) 855 { 856 857 /* 858 * We track errors and successfull sends with this logic: 859 * - Any error resets success counter to 0. 860 * - MAX_ERRORS triggers demotion. 861 * - MIN_SUCCESS successes resets error counter to 0. 862 * - MIN_SUCCESS reverts demotion, if it was triggered before. 863 */ 864 if (error) { 865 if (sc->sc_sendad_errors < INT_MAX) 866 sc->sc_sendad_errors++; 867 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 868 static const char fmt[] = "send error %d on %s"; 869 char msg[sizeof(fmt) + IFNAMSIZ]; 870 871 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 872 carp_demote_adj(V_carp_senderr_adj, msg); 873 } 874 sc->sc_sendad_success = 0; 875 } else if (sc->sc_sendad_errors > 0) { 876 if (++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 877 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS) { 878 static const char fmt[] = "send ok on %s"; 879 char msg[sizeof(fmt) + IFNAMSIZ]; 880 881 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 882 carp_demote_adj(-V_carp_senderr_adj, msg); 883 } 884 sc->sc_sendad_errors = 0; 885 } 886 } 887 } 888 889 /* 890 * Pick the best ifaddr on the given ifp for sending CARP 891 * advertisements. 892 * 893 * "Best" here is defined by ifa_preferred(). This function is much 894 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 895 * 896 * (This could be simplified to return the actual address, except that 897 * it has a different format in AF_INET and AF_INET6.) 898 */ 899 static struct ifaddr * 900 carp_best_ifa(int af, struct ifnet *ifp) 901 { 902 struct ifaddr *ifa, *best; 903 904 NET_EPOCH_ASSERT(); 905 906 if (af >= AF_MAX) 907 return (NULL); 908 best = NULL; 909 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 910 if (ifa->ifa_addr->sa_family == af && 911 (best == NULL || ifa_preferred(best, ifa))) 912 best = ifa; 913 } 914 if (best != NULL) 915 ifa_ref(best); 916 return (best); 917 } 918 919 static void 920 carp_send_ad_locked(struct carp_softc *sc) 921 { 922 struct carp_header ch; 923 struct timeval tv; 924 struct ifaddr *ifa; 925 struct carp_header *ch_ptr; 926 struct mbuf *m; 927 int len, advskew; 928 929 NET_EPOCH_ASSERT(); 930 CARP_LOCK_ASSERT(sc); 931 932 advskew = DEMOTE_ADVSKEW(sc); 933 tv.tv_sec = sc->sc_advbase; 934 tv.tv_usec = advskew * 1000000 / 256; 935 936 ch.carp_version = CARP_VERSION; 937 ch.carp_type = CARP_ADVERTISEMENT; 938 ch.carp_vhid = sc->sc_vhid; 939 ch.carp_advbase = sc->sc_advbase; 940 ch.carp_advskew = advskew; 941 ch.carp_authlen = 7; /* XXX DEFINE */ 942 ch.carp_pad1 = 0; /* must be zero */ 943 ch.carp_cksum = 0; 944 945 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 946 947 #ifdef INET 948 if (sc->sc_naddrs) { 949 struct ip *ip; 950 951 m = m_gethdr(M_NOWAIT, MT_DATA); 952 if (m == NULL) { 953 CARPSTATS_INC(carps_onomem); 954 goto resched; 955 } 956 len = sizeof(*ip) + sizeof(ch); 957 m->m_pkthdr.len = len; 958 m->m_pkthdr.rcvif = NULL; 959 m->m_len = len; 960 M_ALIGN(m, m->m_len); 961 m->m_flags |= M_MCAST; 962 ip = mtod(m, struct ip *); 963 ip->ip_v = IPVERSION; 964 ip->ip_hl = sizeof(*ip) >> 2; 965 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET; 966 ip->ip_len = htons(len); 967 ip->ip_off = htons(IP_DF); 968 ip->ip_ttl = CARP_DFLTTL; 969 ip->ip_p = IPPROTO_CARP; 970 ip->ip_sum = 0; 971 ip_fillid(ip); 972 973 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 974 if (ifa != NULL) { 975 ip->ip_src.s_addr = 976 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 977 ifa_free(ifa); 978 } else 979 ip->ip_src.s_addr = 0; 980 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 981 982 ch_ptr = (struct carp_header *)(&ip[1]); 983 bcopy(&ch, ch_ptr, sizeof(ch)); 984 if (carp_prepare_ad(m, sc, ch_ptr)) 985 goto resched; 986 987 m->m_data += sizeof(*ip); 988 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 989 m->m_data -= sizeof(*ip); 990 991 CARPSTATS_INC(carps_opackets); 992 993 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 994 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 995 } 996 #endif /* INET */ 997 #ifdef INET6 998 if (sc->sc_naddrs6) { 999 struct ip6_hdr *ip6; 1000 1001 m = m_gethdr(M_NOWAIT, MT_DATA); 1002 if (m == NULL) { 1003 CARPSTATS_INC(carps_onomem); 1004 goto resched; 1005 } 1006 len = sizeof(*ip6) + sizeof(ch); 1007 m->m_pkthdr.len = len; 1008 m->m_pkthdr.rcvif = NULL; 1009 m->m_len = len; 1010 M_ALIGN(m, m->m_len); 1011 m->m_flags |= M_MCAST; 1012 ip6 = mtod(m, struct ip6_hdr *); 1013 bzero(ip6, sizeof(*ip6)); 1014 ip6->ip6_vfc |= IPV6_VERSION; 1015 /* Traffic class isn't defined in ip6 struct instead 1016 * it gets offset into flowid field */ 1017 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN + 1018 IPTOS_DSCP_OFFSET)); 1019 ip6->ip6_hlim = CARP_DFLTTL; 1020 ip6->ip6_nxt = IPPROTO_CARP; 1021 1022 /* set the source address */ 1023 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 1024 if (ifa != NULL) { 1025 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 1026 sizeof(struct in6_addr)); 1027 ifa_free(ifa); 1028 } else 1029 /* This should never happen with IPv6. */ 1030 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 1031 1032 /* Set the multicast destination. */ 1033 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1034 ip6->ip6_dst.s6_addr8[15] = 0x12; 1035 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1036 m_freem(m); 1037 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1038 goto resched; 1039 } 1040 1041 ch_ptr = (struct carp_header *)(&ip6[1]); 1042 bcopy(&ch, ch_ptr, sizeof(ch)); 1043 if (carp_prepare_ad(m, sc, ch_ptr)) 1044 goto resched; 1045 1046 m->m_data += sizeof(*ip6); 1047 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1048 m->m_data -= sizeof(*ip6); 1049 1050 CARPSTATS_INC(carps_opackets6); 1051 1052 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1053 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1054 } 1055 #endif /* INET6 */ 1056 1057 resched: 1058 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1059 } 1060 1061 static void 1062 carp_addroute(struct carp_softc *sc) 1063 { 1064 struct ifaddr *ifa; 1065 1066 CARP_FOREACH_IFA(sc, ifa) 1067 carp_ifa_addroute(ifa); 1068 } 1069 1070 static void 1071 carp_ifa_addroute(struct ifaddr *ifa) 1072 { 1073 1074 switch (ifa->ifa_addr->sa_family) { 1075 #ifdef INET 1076 case AF_INET: 1077 in_addprefix(ifatoia(ifa)); 1078 ifa_add_loopback_route(ifa, 1079 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1080 break; 1081 #endif 1082 #ifdef INET6 1083 case AF_INET6: 1084 ifa_add_loopback_route(ifa, 1085 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1086 nd6_add_ifa_lle(ifatoia6(ifa)); 1087 break; 1088 #endif 1089 } 1090 } 1091 1092 static void 1093 carp_delroute(struct carp_softc *sc) 1094 { 1095 struct ifaddr *ifa; 1096 1097 CARP_FOREACH_IFA(sc, ifa) 1098 carp_ifa_delroute(ifa); 1099 } 1100 1101 static void 1102 carp_ifa_delroute(struct ifaddr *ifa) 1103 { 1104 1105 switch (ifa->ifa_addr->sa_family) { 1106 #ifdef INET 1107 case AF_INET: 1108 ifa_del_loopback_route(ifa, 1109 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1110 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1111 break; 1112 #endif 1113 #ifdef INET6 1114 case AF_INET6: 1115 ifa_del_loopback_route(ifa, 1116 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1117 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1118 break; 1119 #endif 1120 } 1121 } 1122 1123 int 1124 carp_master(struct ifaddr *ifa) 1125 { 1126 struct carp_softc *sc = ifa->ifa_carp; 1127 1128 return (sc->sc_state == MASTER); 1129 } 1130 1131 #ifdef INET 1132 /* 1133 * Broadcast a gratuitous ARP request containing 1134 * the virtual router MAC address for each IP address 1135 * associated with the virtual router. 1136 */ 1137 static void 1138 carp_send_arp(struct carp_softc *sc) 1139 { 1140 struct ifaddr *ifa; 1141 struct in_addr addr; 1142 1143 NET_EPOCH_ASSERT(); 1144 1145 CARP_FOREACH_IFA(sc, ifa) { 1146 if (ifa->ifa_addr->sa_family != AF_INET) 1147 continue; 1148 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1149 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1150 } 1151 } 1152 1153 int 1154 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1155 { 1156 struct carp_softc *sc = ifa->ifa_carp; 1157 1158 if (sc->sc_state == MASTER) { 1159 *enaddr = LLADDR(&sc->sc_addr); 1160 return (1); 1161 } 1162 1163 return (0); 1164 } 1165 #endif 1166 1167 #ifdef INET6 1168 static void 1169 carp_send_na(struct carp_softc *sc) 1170 { 1171 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1172 struct ifaddr *ifa; 1173 struct in6_addr *in6; 1174 1175 CARP_FOREACH_IFA(sc, ifa) { 1176 if (ifa->ifa_addr->sa_family != AF_INET6) 1177 continue; 1178 1179 in6 = IFA_IN6(ifa); 1180 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1181 ND_NA_FLAG_OVERRIDE, 1, NULL); 1182 DELAY(1000); /* XXX */ 1183 } 1184 } 1185 1186 /* 1187 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1188 * matches and is not a carp address. Returns NULL otherwise. 1189 */ 1190 struct ifaddr * 1191 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1192 { 1193 struct ifaddr *ifa; 1194 1195 NET_EPOCH_ASSERT(); 1196 1197 ifa = NULL; 1198 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1199 if (ifa->ifa_addr->sa_family != AF_INET6) 1200 continue; 1201 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1202 continue; 1203 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1204 ifa = NULL; 1205 else 1206 ifa_ref(ifa); 1207 break; 1208 } 1209 1210 return (ifa); 1211 } 1212 1213 char * 1214 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1215 { 1216 struct ifaddr *ifa; 1217 1218 NET_EPOCH_ASSERT(); 1219 1220 IFNET_FOREACH_IFA(ifp, ifa) 1221 if (ifa->ifa_addr->sa_family == AF_INET6 && 1222 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1223 struct carp_softc *sc = ifa->ifa_carp; 1224 struct m_tag *mtag; 1225 1226 mtag = m_tag_get(PACKET_TAG_CARP, 1227 sizeof(struct carp_softc *), M_NOWAIT); 1228 if (mtag == NULL) 1229 /* Better a bit than nothing. */ 1230 return (LLADDR(&sc->sc_addr)); 1231 1232 bcopy(&sc, mtag + 1, sizeof(sc)); 1233 m_tag_prepend(m, mtag); 1234 1235 return (LLADDR(&sc->sc_addr)); 1236 } 1237 1238 return (NULL); 1239 } 1240 #endif /* INET6 */ 1241 1242 int 1243 carp_forus(struct ifnet *ifp, u_char *dhost) 1244 { 1245 struct carp_softc *sc; 1246 uint8_t *ena = dhost; 1247 1248 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1249 return (0); 1250 1251 CIF_LOCK(ifp->if_carp); 1252 IFNET_FOREACH_CARP(ifp, sc) { 1253 /* 1254 * CARP_LOCK() is not here, since would protect nothing, but 1255 * cause deadlock with if_bridge, calling this under its lock. 1256 */ 1257 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1258 ETHER_ADDR_LEN)) { 1259 CIF_UNLOCK(ifp->if_carp); 1260 return (1); 1261 } 1262 } 1263 CIF_UNLOCK(ifp->if_carp); 1264 1265 return (0); 1266 } 1267 1268 /* Master down timeout event, executed in callout context. */ 1269 static void 1270 carp_master_down(void *v) 1271 { 1272 struct carp_softc *sc = v; 1273 struct epoch_tracker et; 1274 1275 NET_EPOCH_ENTER(et); 1276 CARP_LOCK_ASSERT(sc); 1277 1278 CURVNET_SET(sc->sc_carpdev->if_vnet); 1279 if (sc->sc_state == BACKUP) { 1280 carp_master_down_locked(sc, "master timed out"); 1281 } 1282 CURVNET_RESTORE(); 1283 1284 CARP_UNLOCK(sc); 1285 NET_EPOCH_EXIT(et); 1286 } 1287 1288 static void 1289 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1290 { 1291 1292 NET_EPOCH_ASSERT(); 1293 CARP_LOCK_ASSERT(sc); 1294 1295 switch (sc->sc_state) { 1296 case BACKUP: 1297 carp_set_state(sc, MASTER, reason); 1298 carp_send_ad_locked(sc); 1299 #ifdef INET 1300 carp_send_arp(sc); 1301 #endif 1302 #ifdef INET6 1303 carp_send_na(sc); 1304 #endif 1305 carp_setrun(sc, 0); 1306 carp_addroute(sc); 1307 break; 1308 case INIT: 1309 case MASTER: 1310 #ifdef INVARIANTS 1311 panic("carp: VHID %u@%s: master_down event in %s state\n", 1312 sc->sc_vhid, 1313 sc->sc_carpdev->if_xname, 1314 sc->sc_state ? "MASTER" : "INIT"); 1315 #endif 1316 break; 1317 } 1318 } 1319 1320 /* 1321 * When in backup state, af indicates whether to reset the master down timer 1322 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1323 */ 1324 static void 1325 carp_setrun(struct carp_softc *sc, sa_family_t af) 1326 { 1327 struct timeval tv; 1328 1329 CARP_LOCK_ASSERT(sc); 1330 1331 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1332 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1333 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1334 !V_carp_allow) 1335 return; 1336 1337 switch (sc->sc_state) { 1338 case INIT: 1339 carp_set_state(sc, BACKUP, "initialization complete"); 1340 carp_setrun(sc, 0); 1341 break; 1342 case BACKUP: 1343 callout_stop(&sc->sc_ad_tmo); 1344 tv.tv_sec = 3 * sc->sc_advbase; 1345 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1346 switch (af) { 1347 #ifdef INET 1348 case AF_INET: 1349 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1350 carp_master_down, sc); 1351 break; 1352 #endif 1353 #ifdef INET6 1354 case AF_INET6: 1355 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1356 carp_master_down, sc); 1357 break; 1358 #endif 1359 default: 1360 #ifdef INET 1361 if (sc->sc_naddrs) 1362 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1363 carp_master_down, sc); 1364 #endif 1365 #ifdef INET6 1366 if (sc->sc_naddrs6) 1367 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1368 carp_master_down, sc); 1369 #endif 1370 break; 1371 } 1372 break; 1373 case MASTER: 1374 tv.tv_sec = sc->sc_advbase; 1375 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1376 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1377 carp_send_ad, sc); 1378 break; 1379 } 1380 } 1381 1382 /* 1383 * Setup multicast structures. 1384 */ 1385 static int 1386 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1387 { 1388 struct ifnet *ifp = cif->cif_ifp; 1389 int error = 0; 1390 1391 switch (sa) { 1392 #ifdef INET 1393 case AF_INET: 1394 { 1395 struct ip_moptions *imo = &cif->cif_imo; 1396 struct in_mfilter *imf; 1397 struct in_addr addr; 1398 1399 if (ip_mfilter_first(&imo->imo_head) != NULL) 1400 return (0); 1401 1402 imf = ip_mfilter_alloc(M_WAITOK, 0, 0); 1403 ip_mfilter_init(&imo->imo_head); 1404 imo->imo_multicast_vif = -1; 1405 1406 addr.s_addr = htonl(INADDR_CARP_GROUP); 1407 if ((error = in_joingroup(ifp, &addr, NULL, 1408 &imf->imf_inm)) != 0) { 1409 ip_mfilter_free(imf); 1410 break; 1411 } 1412 1413 ip_mfilter_insert(&imo->imo_head, imf); 1414 imo->imo_multicast_ifp = ifp; 1415 imo->imo_multicast_ttl = CARP_DFLTTL; 1416 imo->imo_multicast_loop = 0; 1417 break; 1418 } 1419 #endif 1420 #ifdef INET6 1421 case AF_INET6: 1422 { 1423 struct ip6_moptions *im6o = &cif->cif_im6o; 1424 struct in6_mfilter *im6f[2]; 1425 struct in6_addr in6; 1426 1427 if (ip6_mfilter_first(&im6o->im6o_head)) 1428 return (0); 1429 1430 im6f[0] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1431 im6f[1] = ip6_mfilter_alloc(M_WAITOK, 0, 0); 1432 1433 ip6_mfilter_init(&im6o->im6o_head); 1434 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1435 im6o->im6o_multicast_ifp = ifp; 1436 1437 /* Join IPv6 CARP multicast group. */ 1438 bzero(&in6, sizeof(in6)); 1439 in6.s6_addr16[0] = htons(0xff02); 1440 in6.s6_addr8[15] = 0x12; 1441 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1442 ip6_mfilter_free(im6f[0]); 1443 ip6_mfilter_free(im6f[1]); 1444 break; 1445 } 1446 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[0]->im6f_in6m, 0)) != 0) { 1447 ip6_mfilter_free(im6f[0]); 1448 ip6_mfilter_free(im6f[1]); 1449 break; 1450 } 1451 1452 /* Join solicited multicast address. */ 1453 bzero(&in6, sizeof(in6)); 1454 in6.s6_addr16[0] = htons(0xff02); 1455 in6.s6_addr32[1] = 0; 1456 in6.s6_addr32[2] = htonl(1); 1457 in6.s6_addr32[3] = 0; 1458 in6.s6_addr8[12] = 0xff; 1459 1460 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1461 ip6_mfilter_free(im6f[0]); 1462 ip6_mfilter_free(im6f[1]); 1463 break; 1464 } 1465 1466 if ((error = in6_joingroup(ifp, &in6, NULL, &im6f[1]->im6f_in6m, 0)) != 0) { 1467 in6_leavegroup(im6f[0]->im6f_in6m, NULL); 1468 ip6_mfilter_free(im6f[0]); 1469 ip6_mfilter_free(im6f[1]); 1470 break; 1471 } 1472 ip6_mfilter_insert(&im6o->im6o_head, im6f[0]); 1473 ip6_mfilter_insert(&im6o->im6o_head, im6f[1]); 1474 break; 1475 } 1476 #endif 1477 } 1478 1479 return (error); 1480 } 1481 1482 /* 1483 * Free multicast structures. 1484 */ 1485 static void 1486 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1487 { 1488 #ifdef INET 1489 struct ip_moptions *imo = &cif->cif_imo; 1490 struct in_mfilter *imf; 1491 #endif 1492 #ifdef INET6 1493 struct ip6_moptions *im6o = &cif->cif_im6o; 1494 struct in6_mfilter *im6f; 1495 #endif 1496 sx_assert(&carp_sx, SA_XLOCKED); 1497 1498 switch (sa) { 1499 #ifdef INET 1500 case AF_INET: 1501 if (cif->cif_naddrs != 0) 1502 break; 1503 1504 while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) { 1505 ip_mfilter_remove(&imo->imo_head, imf); 1506 in_leavegroup(imf->imf_inm, NULL); 1507 ip_mfilter_free(imf); 1508 } 1509 break; 1510 #endif 1511 #ifdef INET6 1512 case AF_INET6: 1513 if (cif->cif_naddrs6 != 0) 1514 break; 1515 1516 while ((im6f = ip6_mfilter_first(&im6o->im6o_head)) != NULL) { 1517 ip6_mfilter_remove(&im6o->im6o_head, im6f); 1518 in6_leavegroup(im6f->im6f_in6m, NULL); 1519 ip6_mfilter_free(im6f); 1520 } 1521 break; 1522 #endif 1523 } 1524 } 1525 1526 int 1527 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1528 { 1529 struct m_tag *mtag; 1530 struct carp_softc *sc; 1531 1532 if (!sa) 1533 return (0); 1534 1535 switch (sa->sa_family) { 1536 #ifdef INET 1537 case AF_INET: 1538 break; 1539 #endif 1540 #ifdef INET6 1541 case AF_INET6: 1542 break; 1543 #endif 1544 default: 1545 return (0); 1546 } 1547 1548 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1549 if (mtag == NULL) 1550 return (0); 1551 1552 bcopy(mtag + 1, &sc, sizeof(sc)); 1553 1554 /* Set the source MAC address to the Virtual Router MAC Address. */ 1555 switch (ifp->if_type) { 1556 case IFT_ETHER: 1557 case IFT_BRIDGE: 1558 case IFT_L2VLAN: { 1559 struct ether_header *eh; 1560 1561 eh = mtod(m, struct ether_header *); 1562 eh->ether_shost[0] = 0; 1563 eh->ether_shost[1] = 0; 1564 eh->ether_shost[2] = 0x5e; 1565 eh->ether_shost[3] = 0; 1566 eh->ether_shost[4] = 1; 1567 eh->ether_shost[5] = sc->sc_vhid; 1568 } 1569 break; 1570 default: 1571 printf("%s: carp is not supported for the %d interface type\n", 1572 ifp->if_xname, ifp->if_type); 1573 return (EOPNOTSUPP); 1574 } 1575 1576 return (0); 1577 } 1578 1579 static struct carp_softc* 1580 carp_alloc(struct ifnet *ifp) 1581 { 1582 struct carp_softc *sc; 1583 struct carp_if *cif; 1584 1585 sx_assert(&carp_sx, SA_XLOCKED); 1586 1587 if ((cif = ifp->if_carp) == NULL) 1588 cif = carp_alloc_if(ifp); 1589 1590 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1591 1592 sc->sc_advbase = CARP_DFLTINTV; 1593 sc->sc_vhid = -1; /* required setting */ 1594 sc->sc_init_counter = 1; 1595 sc->sc_state = INIT; 1596 1597 sc->sc_ifasiz = sizeof(struct ifaddr *); 1598 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1599 sc->sc_carpdev = ifp; 1600 1601 CARP_LOCK_INIT(sc); 1602 #ifdef INET 1603 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1604 #endif 1605 #ifdef INET6 1606 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1607 #endif 1608 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1609 1610 CIF_LOCK(cif); 1611 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1612 CIF_UNLOCK(cif); 1613 1614 mtx_lock(&carp_mtx); 1615 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1616 mtx_unlock(&carp_mtx); 1617 1618 return (sc); 1619 } 1620 1621 static void 1622 carp_grow_ifas(struct carp_softc *sc) 1623 { 1624 struct ifaddr **new; 1625 1626 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1627 CARP_LOCK(sc); 1628 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1629 free(sc->sc_ifas, M_CARP); 1630 sc->sc_ifas = new; 1631 sc->sc_ifasiz *= 2; 1632 CARP_UNLOCK(sc); 1633 } 1634 1635 static void 1636 carp_destroy(struct carp_softc *sc) 1637 { 1638 struct ifnet *ifp = sc->sc_carpdev; 1639 struct carp_if *cif = ifp->if_carp; 1640 1641 sx_assert(&carp_sx, SA_XLOCKED); 1642 1643 if (sc->sc_suppress) 1644 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1645 CARP_UNLOCK(sc); 1646 1647 CIF_LOCK(cif); 1648 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1649 CIF_UNLOCK(cif); 1650 1651 mtx_lock(&carp_mtx); 1652 LIST_REMOVE(sc, sc_next); 1653 mtx_unlock(&carp_mtx); 1654 1655 callout_drain(&sc->sc_ad_tmo); 1656 #ifdef INET 1657 callout_drain(&sc->sc_md_tmo); 1658 #endif 1659 #ifdef INET6 1660 callout_drain(&sc->sc_md6_tmo); 1661 #endif 1662 CARP_LOCK_DESTROY(sc); 1663 1664 free(sc->sc_ifas, M_CARP); 1665 free(sc, M_CARP); 1666 } 1667 1668 static struct carp_if* 1669 carp_alloc_if(struct ifnet *ifp) 1670 { 1671 struct carp_if *cif; 1672 int error; 1673 1674 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1675 1676 if ((error = ifpromisc(ifp, 1)) != 0) 1677 printf("%s: ifpromisc(%s) failed: %d\n", 1678 __func__, ifp->if_xname, error); 1679 else 1680 cif->cif_flags |= CIF_PROMISC; 1681 1682 CIF_LOCK_INIT(cif); 1683 cif->cif_ifp = ifp; 1684 TAILQ_INIT(&cif->cif_vrs); 1685 1686 IF_ADDR_WLOCK(ifp); 1687 ifp->if_carp = cif; 1688 if_ref(ifp); 1689 IF_ADDR_WUNLOCK(ifp); 1690 1691 return (cif); 1692 } 1693 1694 static void 1695 carp_free_if(struct carp_if *cif) 1696 { 1697 struct ifnet *ifp = cif->cif_ifp; 1698 1699 CIF_LOCK_ASSERT(cif); 1700 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1701 __func__)); 1702 1703 IF_ADDR_WLOCK(ifp); 1704 ifp->if_carp = NULL; 1705 IF_ADDR_WUNLOCK(ifp); 1706 1707 CIF_LOCK_DESTROY(cif); 1708 1709 if (cif->cif_flags & CIF_PROMISC) 1710 ifpromisc(ifp, 0); 1711 if_rele(ifp); 1712 1713 free(cif, M_CARP); 1714 } 1715 1716 static void 1717 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1718 { 1719 1720 CARP_LOCK(sc); 1721 carpr->carpr_state = sc->sc_state; 1722 carpr->carpr_vhid = sc->sc_vhid; 1723 carpr->carpr_advbase = sc->sc_advbase; 1724 carpr->carpr_advskew = sc->sc_advskew; 1725 if (priv) 1726 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1727 else 1728 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1729 CARP_UNLOCK(sc); 1730 } 1731 1732 int 1733 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1734 { 1735 struct carpreq carpr; 1736 struct ifnet *ifp; 1737 struct carp_softc *sc = NULL; 1738 int error = 0, locked = 0; 1739 1740 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1741 return (error); 1742 1743 ifp = ifunit_ref(ifr->ifr_name); 1744 if (ifp == NULL) 1745 return (ENXIO); 1746 1747 switch (ifp->if_type) { 1748 case IFT_ETHER: 1749 case IFT_L2VLAN: 1750 case IFT_BRIDGE: 1751 break; 1752 default: 1753 error = EOPNOTSUPP; 1754 goto out; 1755 } 1756 1757 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1758 error = EADDRNOTAVAIL; 1759 goto out; 1760 } 1761 1762 sx_xlock(&carp_sx); 1763 switch (cmd) { 1764 case SIOCSVH: 1765 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1766 break; 1767 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1768 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1769 error = EINVAL; 1770 break; 1771 } 1772 1773 if (ifp->if_carp) { 1774 IFNET_FOREACH_CARP(ifp, sc) 1775 if (sc->sc_vhid == carpr.carpr_vhid) 1776 break; 1777 } 1778 if (sc == NULL) { 1779 sc = carp_alloc(ifp); 1780 CARP_LOCK(sc); 1781 sc->sc_vhid = carpr.carpr_vhid; 1782 LLADDR(&sc->sc_addr)[0] = 0; 1783 LLADDR(&sc->sc_addr)[1] = 0; 1784 LLADDR(&sc->sc_addr)[2] = 0x5e; 1785 LLADDR(&sc->sc_addr)[3] = 0; 1786 LLADDR(&sc->sc_addr)[4] = 1; 1787 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1788 } else 1789 CARP_LOCK(sc); 1790 locked = 1; 1791 if (carpr.carpr_advbase > 0) { 1792 if (carpr.carpr_advbase > 255 || 1793 carpr.carpr_advbase < CARP_DFLTINTV) { 1794 error = EINVAL; 1795 break; 1796 } 1797 sc->sc_advbase = carpr.carpr_advbase; 1798 } 1799 if (carpr.carpr_advskew >= 255) { 1800 error = EINVAL; 1801 break; 1802 } 1803 sc->sc_advskew = carpr.carpr_advskew; 1804 if (carpr.carpr_key[0] != '\0') { 1805 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1806 carp_hmac_prepare(sc); 1807 } 1808 if (sc->sc_state != INIT && 1809 carpr.carpr_state != sc->sc_state) { 1810 switch (carpr.carpr_state) { 1811 case BACKUP: 1812 callout_stop(&sc->sc_ad_tmo); 1813 carp_set_state(sc, BACKUP, 1814 "user requested via ifconfig"); 1815 carp_setrun(sc, 0); 1816 carp_delroute(sc); 1817 break; 1818 case MASTER: 1819 carp_master_down_locked(sc, 1820 "user requested via ifconfig"); 1821 break; 1822 default: 1823 break; 1824 } 1825 } 1826 break; 1827 1828 case SIOCGVH: 1829 { 1830 int priveleged; 1831 1832 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1833 error = EINVAL; 1834 break; 1835 } 1836 if (carpr.carpr_count < 1) { 1837 error = EMSGSIZE; 1838 break; 1839 } 1840 if (ifp->if_carp == NULL) { 1841 error = ENOENT; 1842 break; 1843 } 1844 1845 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1846 if (carpr.carpr_vhid != 0) { 1847 IFNET_FOREACH_CARP(ifp, sc) 1848 if (sc->sc_vhid == carpr.carpr_vhid) 1849 break; 1850 if (sc == NULL) { 1851 error = ENOENT; 1852 break; 1853 } 1854 carp_carprcp(&carpr, sc, priveleged); 1855 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1856 sizeof(carpr)); 1857 } else { 1858 int i, count; 1859 1860 count = 0; 1861 IFNET_FOREACH_CARP(ifp, sc) 1862 count++; 1863 1864 if (count > carpr.carpr_count) { 1865 CIF_UNLOCK(ifp->if_carp); 1866 error = EMSGSIZE; 1867 break; 1868 } 1869 1870 i = 0; 1871 IFNET_FOREACH_CARP(ifp, sc) { 1872 carp_carprcp(&carpr, sc, priveleged); 1873 carpr.carpr_count = count; 1874 error = copyout(&carpr, 1875 (char *)ifr_data_get_ptr(ifr) + 1876 (i * sizeof(carpr)), sizeof(carpr)); 1877 if (error) { 1878 CIF_UNLOCK(ifp->if_carp); 1879 break; 1880 } 1881 i++; 1882 } 1883 } 1884 break; 1885 } 1886 default: 1887 error = EINVAL; 1888 } 1889 sx_xunlock(&carp_sx); 1890 1891 out: 1892 if (locked) 1893 CARP_UNLOCK(sc); 1894 if_rele(ifp); 1895 1896 return (error); 1897 } 1898 1899 static int 1900 carp_get_vhid(struct ifaddr *ifa) 1901 { 1902 1903 if (ifa == NULL || ifa->ifa_carp == NULL) 1904 return (0); 1905 1906 return (ifa->ifa_carp->sc_vhid); 1907 } 1908 1909 int 1910 carp_attach(struct ifaddr *ifa, int vhid) 1911 { 1912 struct ifnet *ifp = ifa->ifa_ifp; 1913 struct carp_if *cif = ifp->if_carp; 1914 struct carp_softc *sc; 1915 int index, error; 1916 1917 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1918 1919 switch (ifa->ifa_addr->sa_family) { 1920 #ifdef INET 1921 case AF_INET: 1922 #endif 1923 #ifdef INET6 1924 case AF_INET6: 1925 #endif 1926 break; 1927 default: 1928 return (EPROTOTYPE); 1929 } 1930 1931 sx_xlock(&carp_sx); 1932 if (ifp->if_carp == NULL) { 1933 sx_xunlock(&carp_sx); 1934 return (ENOPROTOOPT); 1935 } 1936 1937 IFNET_FOREACH_CARP(ifp, sc) 1938 if (sc->sc_vhid == vhid) 1939 break; 1940 if (sc == NULL) { 1941 sx_xunlock(&carp_sx); 1942 return (ENOENT); 1943 } 1944 1945 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1946 if (error) { 1947 CIF_FREE(cif); 1948 sx_xunlock(&carp_sx); 1949 return (error); 1950 } 1951 1952 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1953 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1954 carp_grow_ifas(sc); 1955 1956 switch (ifa->ifa_addr->sa_family) { 1957 #ifdef INET 1958 case AF_INET: 1959 cif->cif_naddrs++; 1960 sc->sc_naddrs++; 1961 break; 1962 #endif 1963 #ifdef INET6 1964 case AF_INET6: 1965 cif->cif_naddrs6++; 1966 sc->sc_naddrs6++; 1967 break; 1968 #endif 1969 } 1970 1971 ifa_ref(ifa); 1972 1973 CARP_LOCK(sc); 1974 sc->sc_ifas[index - 1] = ifa; 1975 ifa->ifa_carp = sc; 1976 carp_hmac_prepare(sc); 1977 carp_sc_state(sc); 1978 CARP_UNLOCK(sc); 1979 1980 sx_xunlock(&carp_sx); 1981 1982 return (0); 1983 } 1984 1985 void 1986 carp_detach(struct ifaddr *ifa, bool keep_cif) 1987 { 1988 struct ifnet *ifp = ifa->ifa_ifp; 1989 struct carp_if *cif = ifp->if_carp; 1990 struct carp_softc *sc = ifa->ifa_carp; 1991 int i, index; 1992 1993 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1994 1995 sx_xlock(&carp_sx); 1996 1997 CARP_LOCK(sc); 1998 /* Shift array. */ 1999 index = sc->sc_naddrs + sc->sc_naddrs6; 2000 for (i = 0; i < index; i++) 2001 if (sc->sc_ifas[i] == ifa) 2002 break; 2003 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 2004 for (; i < index - 1; i++) 2005 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 2006 sc->sc_ifas[index - 1] = NULL; 2007 2008 switch (ifa->ifa_addr->sa_family) { 2009 #ifdef INET 2010 case AF_INET: 2011 cif->cif_naddrs--; 2012 sc->sc_naddrs--; 2013 break; 2014 #endif 2015 #ifdef INET6 2016 case AF_INET6: 2017 cif->cif_naddrs6--; 2018 sc->sc_naddrs6--; 2019 break; 2020 #endif 2021 } 2022 2023 carp_ifa_delroute(ifa); 2024 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 2025 2026 ifa->ifa_carp = NULL; 2027 ifa_free(ifa); 2028 2029 carp_hmac_prepare(sc); 2030 carp_sc_state(sc); 2031 2032 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2033 carp_destroy(sc); 2034 else 2035 CARP_UNLOCK(sc); 2036 2037 if (!keep_cif) 2038 CIF_FREE(cif); 2039 2040 sx_xunlock(&carp_sx); 2041 } 2042 2043 static void 2044 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2045 { 2046 2047 CARP_LOCK_ASSERT(sc); 2048 2049 if (sc->sc_state != state) { 2050 const char *carp_states[] = { CARP_STATES }; 2051 char subsys[IFNAMSIZ+5]; 2052 2053 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2054 sc->sc_carpdev->if_xname); 2055 2056 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2057 carp_states[sc->sc_state], carp_states[state], reason); 2058 2059 sc->sc_state = state; 2060 2061 devctl_notify("CARP", subsys, carp_states[state], NULL); 2062 } 2063 } 2064 2065 static void 2066 carp_linkstate(struct ifnet *ifp) 2067 { 2068 struct carp_softc *sc; 2069 2070 CIF_LOCK(ifp->if_carp); 2071 IFNET_FOREACH_CARP(ifp, sc) { 2072 CARP_LOCK(sc); 2073 carp_sc_state(sc); 2074 CARP_UNLOCK(sc); 2075 } 2076 CIF_UNLOCK(ifp->if_carp); 2077 } 2078 2079 static void 2080 carp_sc_state(struct carp_softc *sc) 2081 { 2082 2083 CARP_LOCK_ASSERT(sc); 2084 2085 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2086 !(sc->sc_carpdev->if_flags & IFF_UP) || 2087 !V_carp_allow) { 2088 callout_stop(&sc->sc_ad_tmo); 2089 #ifdef INET 2090 callout_stop(&sc->sc_md_tmo); 2091 #endif 2092 #ifdef INET6 2093 callout_stop(&sc->sc_md6_tmo); 2094 #endif 2095 carp_set_state(sc, INIT, "hardware interface down"); 2096 carp_setrun(sc, 0); 2097 if (!sc->sc_suppress) 2098 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2099 sc->sc_suppress = 1; 2100 } else { 2101 carp_set_state(sc, INIT, "hardware interface up"); 2102 carp_setrun(sc, 0); 2103 if (sc->sc_suppress) 2104 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2105 sc->sc_suppress = 0; 2106 } 2107 } 2108 2109 static void 2110 carp_demote_adj(int adj, char *reason) 2111 { 2112 atomic_add_int(&V_carp_demotion, adj); 2113 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2114 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2115 } 2116 2117 static int 2118 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2119 { 2120 int new, error; 2121 struct carp_softc *sc; 2122 2123 new = V_carp_allow; 2124 error = sysctl_handle_int(oidp, &new, 0, req); 2125 if (error || !req->newptr) 2126 return (error); 2127 2128 if (V_carp_allow != new) { 2129 V_carp_allow = new; 2130 2131 mtx_lock(&carp_mtx); 2132 LIST_FOREACH(sc, &carp_list, sc_next) { 2133 CARP_LOCK(sc); 2134 if (curvnet == sc->sc_carpdev->if_vnet) 2135 carp_sc_state(sc); 2136 CARP_UNLOCK(sc); 2137 } 2138 mtx_unlock(&carp_mtx); 2139 } 2140 2141 return (0); 2142 } 2143 2144 static int 2145 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS) 2146 { 2147 int new, error; 2148 2149 new = V_carp_dscp; 2150 error = sysctl_handle_int(oidp, &new, 0, req); 2151 if (error || !req->newptr) 2152 return (error); 2153 2154 if (new < 0 || new > 63) 2155 return (EINVAL); 2156 2157 V_carp_dscp = new; 2158 2159 return (0); 2160 } 2161 2162 static int 2163 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2164 { 2165 int new, error; 2166 2167 new = V_carp_demotion; 2168 error = sysctl_handle_int(oidp, &new, 0, req); 2169 if (error || !req->newptr) 2170 return (error); 2171 2172 carp_demote_adj(new, "sysctl"); 2173 2174 return (0); 2175 } 2176 2177 #ifdef INET 2178 extern struct domain inetdomain; 2179 static struct protosw in_carp_protosw = { 2180 .pr_type = SOCK_RAW, 2181 .pr_domain = &inetdomain, 2182 .pr_protocol = IPPROTO_CARP, 2183 .pr_flags = PR_ATOMIC|PR_ADDR, 2184 .pr_input = carp_input, 2185 .pr_output = rip_output, 2186 .pr_ctloutput = rip_ctloutput, 2187 .pr_usrreqs = &rip_usrreqs 2188 }; 2189 #endif 2190 2191 #ifdef INET6 2192 extern struct domain inet6domain; 2193 static struct protosw in6_carp_protosw = { 2194 .pr_type = SOCK_RAW, 2195 .pr_domain = &inet6domain, 2196 .pr_protocol = IPPROTO_CARP, 2197 .pr_flags = PR_ATOMIC|PR_ADDR, 2198 .pr_input = carp6_input, 2199 .pr_output = rip6_output, 2200 .pr_ctloutput = rip6_ctloutput, 2201 .pr_usrreqs = &rip6_usrreqs 2202 }; 2203 #endif 2204 2205 static void 2206 carp_mod_cleanup(void) 2207 { 2208 2209 #ifdef INET 2210 if (proto_reg[CARP_INET] == 0) { 2211 (void)ipproto_unregister(IPPROTO_CARP); 2212 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2213 proto_reg[CARP_INET] = -1; 2214 } 2215 carp_iamatch_p = NULL; 2216 #endif 2217 #ifdef INET6 2218 if (proto_reg[CARP_INET6] == 0) { 2219 (void)ip6proto_unregister(IPPROTO_CARP); 2220 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2221 proto_reg[CARP_INET6] = -1; 2222 } 2223 carp_iamatch6_p = NULL; 2224 carp_macmatch6_p = NULL; 2225 #endif 2226 carp_ioctl_p = NULL; 2227 carp_attach_p = NULL; 2228 carp_detach_p = NULL; 2229 carp_get_vhid_p = NULL; 2230 carp_linkstate_p = NULL; 2231 carp_forus_p = NULL; 2232 carp_output_p = NULL; 2233 carp_demote_adj_p = NULL; 2234 carp_master_p = NULL; 2235 mtx_unlock(&carp_mtx); 2236 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2237 mtx_destroy(&carp_mtx); 2238 sx_destroy(&carp_sx); 2239 } 2240 2241 static int 2242 carp_mod_load(void) 2243 { 2244 int err; 2245 2246 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2247 sx_init(&carp_sx, "carp_sx"); 2248 LIST_INIT(&carp_list); 2249 carp_get_vhid_p = carp_get_vhid; 2250 carp_forus_p = carp_forus; 2251 carp_output_p = carp_output; 2252 carp_linkstate_p = carp_linkstate; 2253 carp_ioctl_p = carp_ioctl; 2254 carp_attach_p = carp_attach; 2255 carp_detach_p = carp_detach; 2256 carp_demote_adj_p = carp_demote_adj; 2257 carp_master_p = carp_master; 2258 #ifdef INET6 2259 carp_iamatch6_p = carp_iamatch6; 2260 carp_macmatch6_p = carp_macmatch6; 2261 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2262 (struct protosw *)&in6_carp_protosw); 2263 if (proto_reg[CARP_INET6]) { 2264 printf("carp: error %d attaching to PF_INET6\n", 2265 proto_reg[CARP_INET6]); 2266 carp_mod_cleanup(); 2267 return (proto_reg[CARP_INET6]); 2268 } 2269 err = ip6proto_register(IPPROTO_CARP); 2270 if (err) { 2271 printf("carp: error %d registering with INET6\n", err); 2272 carp_mod_cleanup(); 2273 return (err); 2274 } 2275 #endif 2276 #ifdef INET 2277 carp_iamatch_p = carp_iamatch; 2278 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2279 if (proto_reg[CARP_INET]) { 2280 printf("carp: error %d attaching to PF_INET\n", 2281 proto_reg[CARP_INET]); 2282 carp_mod_cleanup(); 2283 return (proto_reg[CARP_INET]); 2284 } 2285 err = ipproto_register(IPPROTO_CARP); 2286 if (err) { 2287 printf("carp: error %d registering with INET\n", err); 2288 carp_mod_cleanup(); 2289 return (err); 2290 } 2291 #endif 2292 return (0); 2293 } 2294 2295 static int 2296 carp_modevent(module_t mod, int type, void *data) 2297 { 2298 switch (type) { 2299 case MOD_LOAD: 2300 return carp_mod_load(); 2301 /* NOTREACHED */ 2302 case MOD_UNLOAD: 2303 mtx_lock(&carp_mtx); 2304 if (LIST_EMPTY(&carp_list)) 2305 carp_mod_cleanup(); 2306 else { 2307 mtx_unlock(&carp_mtx); 2308 return (EBUSY); 2309 } 2310 break; 2311 2312 default: 2313 return (EINVAL); 2314 } 2315 2316 return (0); 2317 } 2318 2319 static moduledata_t carp_mod = { 2320 "carp", 2321 carp_modevent, 2322 0 2323 }; 2324 2325 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY); 2326