Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet/ip_carp.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
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: releng/12.0/sys/netinet/ip_carp.c 340109 2018-11-04 06:25:07Z bz $"); 33 34 #include "opt_bpf.h" 35 #include "opt_inet.h" 36 #include "opt_inet6.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bus.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/limits.h> 44 #include <sys/malloc.h> 45 #include <sys/mbuf.h> 46 #include <sys/module.h> 47 #include <sys/priv.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/sockio.h> 52 #include <sys/sysctl.h> 53 #include <sys/syslog.h> 54 #include <sys/taskqueue.h> 55 #include <sys/counter.h> 56 57 #include <net/ethernet.h> 58 #include <net/if.h> 59 #include <net/if_var.h> 60 #include <net/if_dl.h> 61 #include <net/if_llatbl.h> 62 #include <net/if_types.h> 63 #include <net/route.h> 64 #include <net/vnet.h> 65 66 #if defined(INET) || defined(INET6) 67 #include <netinet/in.h> 68 #include <netinet/in_var.h> 69 #include <netinet/ip_carp.h> 70 #include <netinet/ip.h> 71 #include <machine/in_cksum.h> 72 #endif 73 #ifdef INET 74 #include <netinet/ip_var.h> 75 #include <netinet/if_ether.h> 76 #endif 77 78 #ifdef INET6 79 #include <netinet/icmp6.h> 80 #include <netinet/ip6.h> 81 #include <netinet6/in6_var.h> 82 #include <netinet6/ip6_var.h> 83 #include <netinet6/scope6_var.h> 84 #include <netinet6/nd6.h> 85 #endif 86 87 #include <crypto/sha1.h> 88 89 static MALLOC_DEFINE(M_CARP, "CARP", "CARP addresses"); 90 91 struct carp_softc { 92 struct ifnet *sc_carpdev; /* Pointer to parent ifnet. */ 93 struct ifaddr **sc_ifas; /* Our ifaddrs. */ 94 struct sockaddr_dl sc_addr; /* Our link level address. */ 95 struct callout sc_ad_tmo; /* Advertising timeout. */ 96 #ifdef INET 97 struct callout sc_md_tmo; /* Master down timeout. */ 98 #endif 99 #ifdef INET6 100 struct callout sc_md6_tmo; /* XXX: Master down timeout. */ 101 #endif 102 struct mtx sc_mtx; 103 104 int sc_vhid; 105 int sc_advskew; 106 int sc_advbase; 107 108 int sc_naddrs; 109 int sc_naddrs6; 110 int sc_ifasiz; 111 enum { INIT = 0, BACKUP, MASTER } sc_state; 112 int sc_suppress; 113 int sc_sendad_errors; 114 #define CARP_SENDAD_MAX_ERRORS 3 115 int sc_sendad_success; 116 #define CARP_SENDAD_MIN_SUCCESS 3 117 118 int sc_init_counter; 119 uint64_t sc_counter; 120 121 /* authentication */ 122 #define CARP_HMAC_PAD 64 123 unsigned char sc_key[CARP_KEY_LEN]; 124 unsigned char sc_pad[CARP_HMAC_PAD]; 125 SHA1_CTX sc_sha1; 126 127 TAILQ_ENTRY(carp_softc) sc_list; /* On the carp_if list. */ 128 LIST_ENTRY(carp_softc) sc_next; /* On the global list. */ 129 }; 130 131 struct carp_if { 132 #ifdef INET 133 int cif_naddrs; 134 #endif 135 #ifdef INET6 136 int cif_naddrs6; 137 #endif 138 TAILQ_HEAD(, carp_softc) cif_vrs; 139 #ifdef INET 140 struct ip_moptions cif_imo; 141 #endif 142 #ifdef INET6 143 struct ip6_moptions cif_im6o; 144 #endif 145 struct ifnet *cif_ifp; 146 struct mtx cif_mtx; 147 uint32_t cif_flags; 148 #define CIF_PROMISC 0x00000001 149 }; 150 151 #define CARP_INET 0 152 #define CARP_INET6 1 153 static int proto_reg[] = {-1, -1}; 154 155 /* 156 * Brief design of carp(4). 157 * 158 * Any carp-capable ifnet may have a list of carp softcs hanging off 159 * its ifp->if_carp pointer. Each softc represents one unique virtual 160 * host id, or vhid. The softc has a back pointer to the ifnet. All 161 * softcs are joined in a global list, which has quite limited use. 162 * 163 * Any interface address that takes part in CARP negotiation has a 164 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either 165 * AF_INET or AF_INET6 address. 166 * 167 * Although, one can get the softc's backpointer to ifnet and traverse 168 * through its ifp->if_addrhead queue to find all interface addresses 169 * involved in CARP, we keep a growable array of ifaddr pointers. This 170 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that 171 * do calls into the network stack, thus avoiding LORs. 172 * 173 * Locking: 174 * 175 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(), 176 * callout-driven events and ioctl()s. 177 * 178 * To traverse the list of softcs on an ifnet we use CIF_LOCK() or carp_sx. 179 * To traverse the global list we use the mutex carp_mtx. 180 * 181 * Known issues with locking: 182 * 183 * - Sending ad, we put the pointer to the softc in an mtag, and no reference 184 * counting is done on the softc. 185 * - On module unload we may race (?) with packet processing thread 186 * dereferencing our function pointers. 187 */ 188 189 /* Accept incoming CARP packets. */ 190 VNET_DEFINE_STATIC(int, carp_allow) = 1; 191 #define V_carp_allow VNET(carp_allow) 192 193 /* Set DSCP in outgoing CARP packets. */ 194 VNET_DEFINE_STATIC(int, carp_dscp) = 56; 195 #define V_carp_dscp VNET(carp_dscp) 196 197 /* Preempt slower nodes. */ 198 VNET_DEFINE_STATIC(int, carp_preempt) = 0; 199 #define V_carp_preempt VNET(carp_preempt) 200 201 /* Log level. */ 202 VNET_DEFINE_STATIC(int, carp_log) = 1; 203 #define V_carp_log VNET(carp_log) 204 205 /* Global advskew demotion. */ 206 VNET_DEFINE_STATIC(int, carp_demotion) = 0; 207 #define V_carp_demotion VNET(carp_demotion) 208 209 /* Send error demotion factor. */ 210 VNET_DEFINE_STATIC(int, carp_senderr_adj) = CARP_MAXSKEW; 211 #define V_carp_senderr_adj VNET(carp_senderr_adj) 212 213 /* Iface down demotion factor. */ 214 VNET_DEFINE_STATIC(int, carp_ifdown_adj) = CARP_MAXSKEW; 215 #define V_carp_ifdown_adj VNET(carp_ifdown_adj) 216 217 static int carp_allow_sysctl(SYSCTL_HANDLER_ARGS); 218 static int carp_dscp_sysctl(SYSCTL_HANDLER_ARGS); 219 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS); 220 221 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW, 0, "CARP"); 222 SYSCTL_PROC(_net_inet_carp, OID_AUTO, allow, 223 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_allow_sysctl, "I", 224 "Accept incoming CARP packets"); 225 SYSCTL_PROC(_net_inet_carp, OID_AUTO, dscp, 226 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 0, 0, carp_dscp_sysctl, "I", 227 "DSCP value for carp packets"); 228 SYSCTL_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_VNET | CTLFLAG_RW, 229 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode"); 230 SYSCTL_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_VNET | CTLFLAG_RW, 231 &VNET_NAME(carp_log), 0, "CARP log level"); 232 SYSCTL_PROC(_net_inet_carp, OID_AUTO, demotion, 233 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, 234 0, 0, carp_demote_adj_sysctl, "I", 235 "Adjust demotion factor (skew of advskew)"); 236 SYSCTL_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, 237 CTLFLAG_VNET | CTLFLAG_RW, 238 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment"); 239 SYSCTL_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, 240 CTLFLAG_VNET | CTLFLAG_RW, 241 &VNET_NAME(carp_ifdown_adj), 0, 242 "Interface down demotion factor adjustment"); 243 244 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats); 245 VNET_PCPUSTAT_SYSINIT(carpstats); 246 VNET_PCPUSTAT_SYSUNINIT(carpstats); 247 248 #define CARPSTATS_ADD(name, val) \ 249 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \ 250 sizeof(uint64_t)], (val)) 251 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1) 252 253 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats, 254 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)"); 255 256 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \ 257 NULL, MTX_DEF) 258 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx) 259 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED) 260 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx) 261 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx) 262 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \ 263 NULL, MTX_DEF) 264 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx) 265 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED) 266 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx) 267 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx) 268 #define CIF_FREE(cif) do { \ 269 CIF_LOCK(cif); \ 270 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \ 271 carp_free_if(cif); \ 272 else \ 273 CIF_UNLOCK(cif); \ 274 } while (0) 275 276 #define CARP_LOG(...) do { \ 277 if (V_carp_log > 0) \ 278 log(LOG_INFO, "carp: " __VA_ARGS__); \ 279 } while (0) 280 281 #define CARP_DEBUG(...) do { \ 282 if (V_carp_log > 1) \ 283 log(LOG_DEBUG, __VA_ARGS__); \ 284 } while (0) 285 286 #define IFNET_FOREACH_IFA(ifp, ifa) \ 287 CK_STAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \ 288 if ((ifa)->ifa_carp != NULL) 289 290 #define CARP_FOREACH_IFA(sc, ifa) \ 291 CARP_LOCK_ASSERT(sc); \ 292 for (int _i = 0; \ 293 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \ 294 ((ifa) = sc->sc_ifas[_i]) != NULL; \ 295 ++_i) 296 297 #define IFNET_FOREACH_CARP(ifp, sc) \ 298 KASSERT(mtx_owned(&ifp->if_carp->cif_mtx) || \ 299 sx_xlocked(&carp_sx), ("cif_vrs not locked")); \ 300 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list) 301 302 #define DEMOTE_ADVSKEW(sc) \ 303 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \ 304 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion)) 305 306 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t); 307 static struct carp_softc 308 *carp_alloc(struct ifnet *); 309 static void carp_destroy(struct carp_softc *); 310 static struct carp_if 311 *carp_alloc_if(struct ifnet *); 312 static void carp_free_if(struct carp_if *); 313 static void carp_set_state(struct carp_softc *, int, const char* reason); 314 static void carp_sc_state(struct carp_softc *); 315 static void carp_setrun(struct carp_softc *, sa_family_t); 316 static void carp_master_down(void *); 317 static void carp_master_down_locked(struct carp_softc *, 318 const char* reason); 319 static void carp_send_ad(void *); 320 static void carp_send_ad_locked(struct carp_softc *); 321 static void carp_addroute(struct carp_softc *); 322 static void carp_ifa_addroute(struct ifaddr *); 323 static void carp_delroute(struct carp_softc *); 324 static void carp_ifa_delroute(struct ifaddr *); 325 static void carp_send_ad_all(void *, int); 326 static void carp_demote_adj(int, char *); 327 328 static LIST_HEAD(, carp_softc) carp_list; 329 static struct mtx carp_mtx; 330 static struct sx carp_sx; 331 static struct task carp_sendall_task = 332 TASK_INITIALIZER(0, carp_send_ad_all, NULL); 333 334 static void 335 carp_hmac_prepare(struct carp_softc *sc) 336 { 337 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT; 338 uint8_t vhid = sc->sc_vhid & 0xff; 339 struct ifaddr *ifa; 340 int i, found; 341 #ifdef INET 342 struct in_addr last, cur, in; 343 #endif 344 #ifdef INET6 345 struct in6_addr last6, cur6, in6; 346 #endif 347 348 CARP_LOCK_ASSERT(sc); 349 350 /* Compute ipad from key. */ 351 bzero(sc->sc_pad, sizeof(sc->sc_pad)); 352 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key)); 353 for (i = 0; i < sizeof(sc->sc_pad); i++) 354 sc->sc_pad[i] ^= 0x36; 355 356 /* Precompute first part of inner hash. */ 357 SHA1Init(&sc->sc_sha1); 358 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad)); 359 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version)); 360 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type)); 361 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid)); 362 #ifdef INET 363 cur.s_addr = 0; 364 do { 365 found = 0; 366 last = cur; 367 cur.s_addr = 0xffffffff; 368 CARP_FOREACH_IFA(sc, ifa) { 369 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr; 370 if (ifa->ifa_addr->sa_family == AF_INET && 371 ntohl(in.s_addr) > ntohl(last.s_addr) && 372 ntohl(in.s_addr) < ntohl(cur.s_addr)) { 373 cur.s_addr = in.s_addr; 374 found++; 375 } 376 } 377 if (found) 378 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur)); 379 } while (found); 380 #endif /* INET */ 381 #ifdef INET6 382 memset(&cur6, 0, sizeof(cur6)); 383 do { 384 found = 0; 385 last6 = cur6; 386 memset(&cur6, 0xff, sizeof(cur6)); 387 CARP_FOREACH_IFA(sc, ifa) { 388 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 389 if (IN6_IS_SCOPE_EMBED(&in6)) 390 in6.s6_addr16[1] = 0; 391 if (ifa->ifa_addr->sa_family == AF_INET6 && 392 memcmp(&in6, &last6, sizeof(in6)) > 0 && 393 memcmp(&in6, &cur6, sizeof(in6)) < 0) { 394 cur6 = in6; 395 found++; 396 } 397 } 398 if (found) 399 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6)); 400 } while (found); 401 #endif /* INET6 */ 402 403 /* convert ipad to opad */ 404 for (i = 0; i < sizeof(sc->sc_pad); i++) 405 sc->sc_pad[i] ^= 0x36 ^ 0x5c; 406 } 407 408 static void 409 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2], 410 unsigned char md[20]) 411 { 412 SHA1_CTX sha1ctx; 413 414 CARP_LOCK_ASSERT(sc); 415 416 /* fetch first half of inner hash */ 417 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx)); 418 419 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter)); 420 SHA1Final(md, &sha1ctx); 421 422 /* outer hash */ 423 SHA1Init(&sha1ctx); 424 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad)); 425 SHA1Update(&sha1ctx, md, 20); 426 SHA1Final(md, &sha1ctx); 427 } 428 429 static int 430 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2], 431 unsigned char md[20]) 432 { 433 unsigned char md2[20]; 434 435 CARP_LOCK_ASSERT(sc); 436 437 carp_hmac_generate(sc, counter, md2); 438 439 return (bcmp(md, md2, sizeof(md2))); 440 } 441 442 /* 443 * process input packet. 444 * we have rearranged checks order compared to the rfc, 445 * but it seems more efficient this way or not possible otherwise. 446 */ 447 #ifdef INET 448 int 449 carp_input(struct mbuf **mp, int *offp, int proto) 450 { 451 struct mbuf *m = *mp; 452 struct ip *ip = mtod(m, struct ip *); 453 struct carp_header *ch; 454 int iplen, len; 455 456 iplen = *offp; 457 *mp = NULL; 458 459 CARPSTATS_INC(carps_ipackets); 460 461 if (!V_carp_allow) { 462 m_freem(m); 463 return (IPPROTO_DONE); 464 } 465 466 /* verify that the IP TTL is 255. */ 467 if (ip->ip_ttl != CARP_DFLTTL) { 468 CARPSTATS_INC(carps_badttl); 469 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 470 ip->ip_ttl, 471 m->m_pkthdr.rcvif->if_xname); 472 m_freem(m); 473 return (IPPROTO_DONE); 474 } 475 476 iplen = ip->ip_hl << 2; 477 478 if (m->m_pkthdr.len < iplen + sizeof(*ch)) { 479 CARPSTATS_INC(carps_badlen); 480 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) " 481 "on %s\n", __func__, m->m_len - sizeof(struct ip), 482 m->m_pkthdr.rcvif->if_xname); 483 m_freem(m); 484 return (IPPROTO_DONE); 485 } 486 487 if (iplen + sizeof(*ch) < m->m_len) { 488 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) { 489 CARPSTATS_INC(carps_hdrops); 490 CARP_DEBUG("%s: pullup failed\n", __func__); 491 return (IPPROTO_DONE); 492 } 493 ip = mtod(m, struct ip *); 494 } 495 ch = (struct carp_header *)((char *)ip + iplen); 496 497 /* 498 * verify that the received packet length is 499 * equal to the CARP header 500 */ 501 len = iplen + sizeof(*ch); 502 if (len > m->m_pkthdr.len) { 503 CARPSTATS_INC(carps_badlen); 504 CARP_DEBUG("%s: packet too short %d on %s\n", __func__, 505 m->m_pkthdr.len, 506 m->m_pkthdr.rcvif->if_xname); 507 m_freem(m); 508 return (IPPROTO_DONE); 509 } 510 511 if ((m = m_pullup(m, len)) == NULL) { 512 CARPSTATS_INC(carps_hdrops); 513 return (IPPROTO_DONE); 514 } 515 ip = mtod(m, struct ip *); 516 ch = (struct carp_header *)((char *)ip + iplen); 517 518 /* verify the CARP checksum */ 519 m->m_data += iplen; 520 if (in_cksum(m, len - iplen)) { 521 CARPSTATS_INC(carps_badsum); 522 CARP_DEBUG("%s: checksum failed on %s\n", __func__, 523 m->m_pkthdr.rcvif->if_xname); 524 m_freem(m); 525 return (IPPROTO_DONE); 526 } 527 m->m_data -= iplen; 528 529 carp_input_c(m, ch, AF_INET); 530 return (IPPROTO_DONE); 531 } 532 #endif 533 534 #ifdef INET6 535 int 536 carp6_input(struct mbuf **mp, int *offp, int proto) 537 { 538 struct mbuf *m = *mp; 539 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 540 struct carp_header *ch; 541 u_int len; 542 543 CARPSTATS_INC(carps_ipackets6); 544 545 if (!V_carp_allow) { 546 m_freem(m); 547 return (IPPROTO_DONE); 548 } 549 550 /* check if received on a valid carp interface */ 551 if (m->m_pkthdr.rcvif->if_carp == NULL) { 552 CARPSTATS_INC(carps_badif); 553 CARP_DEBUG("%s: packet received on non-carp interface: %s\n", 554 __func__, m->m_pkthdr.rcvif->if_xname); 555 m_freem(m); 556 return (IPPROTO_DONE); 557 } 558 559 /* verify that the IP TTL is 255 */ 560 if (ip6->ip6_hlim != CARP_DFLTTL) { 561 CARPSTATS_INC(carps_badttl); 562 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__, 563 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname); 564 m_freem(m); 565 return (IPPROTO_DONE); 566 } 567 568 /* verify that we have a complete carp packet */ 569 len = m->m_len; 570 IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch)); 571 if (ch == NULL) { 572 CARPSTATS_INC(carps_badlen); 573 CARP_DEBUG("%s: packet size %u too small\n", __func__, len); 574 return (IPPROTO_DONE); 575 } 576 577 578 /* verify the CARP checksum */ 579 m->m_data += *offp; 580 if (in_cksum(m, sizeof(*ch))) { 581 CARPSTATS_INC(carps_badsum); 582 CARP_DEBUG("%s: checksum failed, on %s\n", __func__, 583 m->m_pkthdr.rcvif->if_xname); 584 m_freem(m); 585 return (IPPROTO_DONE); 586 } 587 m->m_data -= *offp; 588 589 carp_input_c(m, ch, AF_INET6); 590 return (IPPROTO_DONE); 591 } 592 #endif /* INET6 */ 593 594 /* 595 * This routine should not be necessary at all, but some switches 596 * (VMWare ESX vswitches) can echo our own packets back at us, 597 * and we must ignore them or they will cause us to drop out of 598 * MASTER mode. 599 * 600 * We cannot catch all cases of network loops. Instead, what we 601 * do here is catch any packet that arrives with a carp header 602 * with a VHID of 0, that comes from an address that is our own. 603 * These packets are by definition "from us" (even if they are from 604 * a misconfigured host that is pretending to be us). 605 * 606 * The VHID test is outside this mini-function. 607 */ 608 static int 609 carp_source_is_self(struct mbuf *m, struct ifaddr *ifa, sa_family_t af) 610 { 611 #ifdef INET 612 struct ip *ip4; 613 struct in_addr in4; 614 #endif 615 #ifdef INET6 616 struct ip6_hdr *ip6; 617 struct in6_addr in6; 618 #endif 619 620 switch (af) { 621 #ifdef INET 622 case AF_INET: 623 ip4 = mtod(m, struct ip *); 624 in4 = ifatoia(ifa)->ia_addr.sin_addr; 625 return (in4.s_addr == ip4->ip_src.s_addr); 626 #endif 627 #ifdef INET6 628 case AF_INET6: 629 ip6 = mtod(m, struct ip6_hdr *); 630 in6 = ifatoia6(ifa)->ia_addr.sin6_addr; 631 return (memcmp(&in6, &ip6->ip6_src, sizeof(in6)) == 0); 632 #endif 633 default: 634 break; 635 } 636 return (0); 637 } 638 639 static void 640 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af) 641 { 642 struct ifnet *ifp = m->m_pkthdr.rcvif; 643 struct ifaddr *ifa, *match; 644 struct carp_softc *sc; 645 uint64_t tmp_counter; 646 struct timeval sc_tv, ch_tv; 647 int error; 648 649 /* 650 * Verify that the VHID is valid on the receiving interface. 651 * 652 * There should be just one match. If there are none 653 * the VHID is not valid and we drop the packet. If 654 * there are multiple VHID matches, take just the first 655 * one, for compatibility with previous code. While we're 656 * scanning, check for obvious loops in the network topology 657 * (these should never happen, and as noted above, we may 658 * miss real loops; this is just a double-check). 659 */ 660 IF_ADDR_RLOCK(ifp); 661 error = 0; 662 match = NULL; 663 IFNET_FOREACH_IFA(ifp, ifa) { 664 if (match == NULL && ifa->ifa_carp != NULL && 665 ifa->ifa_addr->sa_family == af && 666 ifa->ifa_carp->sc_vhid == ch->carp_vhid) 667 match = ifa; 668 if (ch->carp_vhid == 0 && carp_source_is_self(m, ifa, af)) 669 error = ELOOP; 670 } 671 ifa = error ? NULL : match; 672 if (ifa != NULL) 673 ifa_ref(ifa); 674 IF_ADDR_RUNLOCK(ifp); 675 676 if (ifa == NULL) { 677 if (error == ELOOP) { 678 CARP_DEBUG("dropping looped packet on interface %s\n", 679 ifp->if_xname); 680 CARPSTATS_INC(carps_badif); /* ??? */ 681 } else { 682 CARPSTATS_INC(carps_badvhid); 683 } 684 m_freem(m); 685 return; 686 } 687 688 /* verify the CARP version. */ 689 if (ch->carp_version != CARP_VERSION) { 690 CARPSTATS_INC(carps_badver); 691 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname, 692 ch->carp_version); 693 ifa_free(ifa); 694 m_freem(m); 695 return; 696 } 697 698 sc = ifa->ifa_carp; 699 CARP_LOCK(sc); 700 ifa_free(ifa); 701 702 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) { 703 CARPSTATS_INC(carps_badauth); 704 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__, 705 sc->sc_vhid, ifp->if_xname); 706 goto out; 707 } 708 709 tmp_counter = ntohl(ch->carp_counter[0]); 710 tmp_counter = tmp_counter<<32; 711 tmp_counter += ntohl(ch->carp_counter[1]); 712 713 /* XXX Replay protection goes here */ 714 715 sc->sc_init_counter = 0; 716 sc->sc_counter = tmp_counter; 717 718 sc_tv.tv_sec = sc->sc_advbase; 719 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256; 720 ch_tv.tv_sec = ch->carp_advbase; 721 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256; 722 723 switch (sc->sc_state) { 724 case INIT: 725 break; 726 case MASTER: 727 /* 728 * If we receive an advertisement from a master who's going to 729 * be more frequent than us, go into BACKUP state. 730 */ 731 if (timevalcmp(&sc_tv, &ch_tv, >) || 732 timevalcmp(&sc_tv, &ch_tv, ==)) { 733 callout_stop(&sc->sc_ad_tmo); 734 carp_set_state(sc, BACKUP, 735 "more frequent advertisement received"); 736 carp_setrun(sc, 0); 737 carp_delroute(sc); 738 } 739 break; 740 case BACKUP: 741 /* 742 * If we're pre-empting masters who advertise slower than us, 743 * and this one claims to be slower, treat him as down. 744 */ 745 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) { 746 carp_master_down_locked(sc, 747 "preempting a slower master"); 748 break; 749 } 750 751 /* 752 * If the master is going to advertise at such a low frequency 753 * that he's guaranteed to time out, we'd might as well just 754 * treat him as timed out now. 755 */ 756 sc_tv.tv_sec = sc->sc_advbase * 3; 757 if (timevalcmp(&sc_tv, &ch_tv, <)) { 758 carp_master_down_locked(sc, "master will time out"); 759 break; 760 } 761 762 /* 763 * Otherwise, we reset the counter and wait for the next 764 * advertisement. 765 */ 766 carp_setrun(sc, af); 767 break; 768 } 769 770 out: 771 CARP_UNLOCK(sc); 772 m_freem(m); 773 } 774 775 static int 776 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch) 777 { 778 struct m_tag *mtag; 779 780 if (sc->sc_init_counter) { 781 /* this could also be seconds since unix epoch */ 782 sc->sc_counter = arc4random(); 783 sc->sc_counter = sc->sc_counter << 32; 784 sc->sc_counter += arc4random(); 785 } else 786 sc->sc_counter++; 787 788 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff); 789 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff); 790 791 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md); 792 793 /* Tag packet for carp_output */ 794 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *), 795 M_NOWAIT)) == NULL) { 796 m_freem(m); 797 CARPSTATS_INC(carps_onomem); 798 return (ENOMEM); 799 } 800 bcopy(&sc, mtag + 1, sizeof(sc)); 801 m_tag_prepend(m, mtag); 802 803 return (0); 804 } 805 806 /* 807 * To avoid LORs and possible recursions this function shouldn't 808 * be called directly, but scheduled via taskqueue. 809 */ 810 static void 811 carp_send_ad_all(void *ctx __unused, int pending __unused) 812 { 813 struct carp_softc *sc; 814 815 mtx_lock(&carp_mtx); 816 LIST_FOREACH(sc, &carp_list, sc_next) 817 if (sc->sc_state == MASTER) { 818 CARP_LOCK(sc); 819 CURVNET_SET(sc->sc_carpdev->if_vnet); 820 carp_send_ad_locked(sc); 821 CURVNET_RESTORE(); 822 CARP_UNLOCK(sc); 823 } 824 mtx_unlock(&carp_mtx); 825 } 826 827 /* Send a periodic advertisement, executed in callout context. */ 828 static void 829 carp_send_ad(void *v) 830 { 831 struct carp_softc *sc = v; 832 833 CARP_LOCK_ASSERT(sc); 834 CURVNET_SET(sc->sc_carpdev->if_vnet); 835 carp_send_ad_locked(sc); 836 CURVNET_RESTORE(); 837 CARP_UNLOCK(sc); 838 } 839 840 static void 841 carp_send_ad_error(struct carp_softc *sc, int error) 842 { 843 844 if (error) { 845 if (sc->sc_sendad_errors < INT_MAX) 846 sc->sc_sendad_errors++; 847 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) { 848 static const char fmt[] = "send error %d on %s"; 849 char msg[sizeof(fmt) + IFNAMSIZ]; 850 851 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname); 852 carp_demote_adj(V_carp_senderr_adj, msg); 853 } 854 sc->sc_sendad_success = 0; 855 } else { 856 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS && 857 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) { 858 static const char fmt[] = "send ok on %s"; 859 char msg[sizeof(fmt) + IFNAMSIZ]; 860 861 sprintf(msg, fmt, sc->sc_carpdev->if_xname); 862 carp_demote_adj(-V_carp_senderr_adj, msg); 863 sc->sc_sendad_errors = 0; 864 } else 865 sc->sc_sendad_errors = 0; 866 } 867 } 868 869 /* 870 * Pick the best ifaddr on the given ifp for sending CARP 871 * advertisements. 872 * 873 * "Best" here is defined by ifa_preferred(). This function is much 874 * much like ifaof_ifpforaddr() except that we just use ifa_preferred(). 875 * 876 * (This could be simplified to return the actual address, except that 877 * it has a different format in AF_INET and AF_INET6.) 878 */ 879 static struct ifaddr * 880 carp_best_ifa(int af, struct ifnet *ifp) 881 { 882 struct ifaddr *ifa, *best; 883 884 if (af >= AF_MAX) 885 return (NULL); 886 best = NULL; 887 IF_ADDR_RLOCK(ifp); 888 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 889 if (ifa->ifa_addr->sa_family == af && 890 (best == NULL || ifa_preferred(best, ifa))) 891 best = ifa; 892 } 893 IF_ADDR_RUNLOCK(ifp); 894 if (best != NULL) 895 ifa_ref(best); 896 return (best); 897 } 898 899 static void 900 carp_send_ad_locked(struct carp_softc *sc) 901 { 902 struct carp_header ch; 903 struct timeval tv; 904 struct ifaddr *ifa; 905 struct carp_header *ch_ptr; 906 struct mbuf *m; 907 int len, advskew; 908 909 CARP_LOCK_ASSERT(sc); 910 911 advskew = DEMOTE_ADVSKEW(sc); 912 tv.tv_sec = sc->sc_advbase; 913 tv.tv_usec = advskew * 1000000 / 256; 914 915 ch.carp_version = CARP_VERSION; 916 ch.carp_type = CARP_ADVERTISEMENT; 917 ch.carp_vhid = sc->sc_vhid; 918 ch.carp_advbase = sc->sc_advbase; 919 ch.carp_advskew = advskew; 920 ch.carp_authlen = 7; /* XXX DEFINE */ 921 ch.carp_pad1 = 0; /* must be zero */ 922 ch.carp_cksum = 0; 923 924 /* XXXGL: OpenBSD picks first ifaddr with needed family. */ 925 926 #ifdef INET 927 if (sc->sc_naddrs) { 928 struct ip *ip; 929 930 m = m_gethdr(M_NOWAIT, MT_DATA); 931 if (m == NULL) { 932 CARPSTATS_INC(carps_onomem); 933 goto resched; 934 } 935 len = sizeof(*ip) + sizeof(ch); 936 m->m_pkthdr.len = len; 937 m->m_pkthdr.rcvif = NULL; 938 m->m_len = len; 939 M_ALIGN(m, m->m_len); 940 m->m_flags |= M_MCAST; 941 ip = mtod(m, struct ip *); 942 ip->ip_v = IPVERSION; 943 ip->ip_hl = sizeof(*ip) >> 2; 944 ip->ip_tos = V_carp_dscp << IPTOS_DSCP_OFFSET; 945 ip->ip_len = htons(len); 946 ip->ip_off = htons(IP_DF); 947 ip->ip_ttl = CARP_DFLTTL; 948 ip->ip_p = IPPROTO_CARP; 949 ip->ip_sum = 0; 950 ip_fillid(ip); 951 952 ifa = carp_best_ifa(AF_INET, sc->sc_carpdev); 953 if (ifa != NULL) { 954 ip->ip_src.s_addr = 955 ifatoia(ifa)->ia_addr.sin_addr.s_addr; 956 ifa_free(ifa); 957 } else 958 ip->ip_src.s_addr = 0; 959 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP); 960 961 ch_ptr = (struct carp_header *)(&ip[1]); 962 bcopy(&ch, ch_ptr, sizeof(ch)); 963 if (carp_prepare_ad(m, sc, ch_ptr)) 964 goto resched; 965 966 m->m_data += sizeof(*ip); 967 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip)); 968 m->m_data -= sizeof(*ip); 969 970 CARPSTATS_INC(carps_opackets); 971 972 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT, 973 &sc->sc_carpdev->if_carp->cif_imo, NULL)); 974 } 975 #endif /* INET */ 976 #ifdef INET6 977 if (sc->sc_naddrs6) { 978 struct ip6_hdr *ip6; 979 980 m = m_gethdr(M_NOWAIT, MT_DATA); 981 if (m == NULL) { 982 CARPSTATS_INC(carps_onomem); 983 goto resched; 984 } 985 len = sizeof(*ip6) + sizeof(ch); 986 m->m_pkthdr.len = len; 987 m->m_pkthdr.rcvif = NULL; 988 m->m_len = len; 989 M_ALIGN(m, m->m_len); 990 m->m_flags |= M_MCAST; 991 ip6 = mtod(m, struct ip6_hdr *); 992 bzero(ip6, sizeof(*ip6)); 993 ip6->ip6_vfc |= IPV6_VERSION; 994 /* Traffic class isn't defined in ip6 struct instead 995 * it gets offset into flowid field */ 996 ip6->ip6_flow |= htonl(V_carp_dscp << (IPV6_FLOWLABEL_LEN + 997 IPTOS_DSCP_OFFSET)); 998 ip6->ip6_hlim = CARP_DFLTTL; 999 ip6->ip6_nxt = IPPROTO_CARP; 1000 1001 /* set the source address */ 1002 ifa = carp_best_ifa(AF_INET6, sc->sc_carpdev); 1003 if (ifa != NULL) { 1004 bcopy(IFA_IN6(ifa), &ip6->ip6_src, 1005 sizeof(struct in6_addr)); 1006 ifa_free(ifa); 1007 } else 1008 /* This should never happen with IPv6. */ 1009 bzero(&ip6->ip6_src, sizeof(struct in6_addr)); 1010 1011 /* Set the multicast destination. */ 1012 ip6->ip6_dst.s6_addr16[0] = htons(0xff02); 1013 ip6->ip6_dst.s6_addr8[15] = 0x12; 1014 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) { 1015 m_freem(m); 1016 CARP_DEBUG("%s: in6_setscope failed\n", __func__); 1017 goto resched; 1018 } 1019 1020 ch_ptr = (struct carp_header *)(&ip6[1]); 1021 bcopy(&ch, ch_ptr, sizeof(ch)); 1022 if (carp_prepare_ad(m, sc, ch_ptr)) 1023 goto resched; 1024 1025 m->m_data += sizeof(*ip6); 1026 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6)); 1027 m->m_data -= sizeof(*ip6); 1028 1029 CARPSTATS_INC(carps_opackets6); 1030 1031 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0, 1032 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL)); 1033 } 1034 #endif /* INET6 */ 1035 1036 resched: 1037 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc); 1038 } 1039 1040 static void 1041 carp_addroute(struct carp_softc *sc) 1042 { 1043 struct ifaddr *ifa; 1044 1045 CARP_FOREACH_IFA(sc, ifa) 1046 carp_ifa_addroute(ifa); 1047 } 1048 1049 static void 1050 carp_ifa_addroute(struct ifaddr *ifa) 1051 { 1052 1053 switch (ifa->ifa_addr->sa_family) { 1054 #ifdef INET 1055 case AF_INET: 1056 in_addprefix(ifatoia(ifa), RTF_UP); 1057 ifa_add_loopback_route(ifa, 1058 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1059 break; 1060 #endif 1061 #ifdef INET6 1062 case AF_INET6: 1063 ifa_add_loopback_route(ifa, 1064 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1065 nd6_add_ifa_lle(ifatoia6(ifa)); 1066 break; 1067 #endif 1068 } 1069 } 1070 1071 static void 1072 carp_delroute(struct carp_softc *sc) 1073 { 1074 struct ifaddr *ifa; 1075 1076 CARP_FOREACH_IFA(sc, ifa) 1077 carp_ifa_delroute(ifa); 1078 } 1079 1080 static void 1081 carp_ifa_delroute(struct ifaddr *ifa) 1082 { 1083 1084 switch (ifa->ifa_addr->sa_family) { 1085 #ifdef INET 1086 case AF_INET: 1087 ifa_del_loopback_route(ifa, 1088 (struct sockaddr *)&ifatoia(ifa)->ia_addr); 1089 in_scrubprefix(ifatoia(ifa), LLE_STATIC); 1090 break; 1091 #endif 1092 #ifdef INET6 1093 case AF_INET6: 1094 ifa_del_loopback_route(ifa, 1095 (struct sockaddr *)&ifatoia6(ifa)->ia_addr); 1096 nd6_rem_ifa_lle(ifatoia6(ifa), 1); 1097 break; 1098 #endif 1099 } 1100 } 1101 1102 int 1103 carp_master(struct ifaddr *ifa) 1104 { 1105 struct carp_softc *sc = ifa->ifa_carp; 1106 1107 return (sc->sc_state == MASTER); 1108 } 1109 1110 #ifdef INET 1111 /* 1112 * Broadcast a gratuitous ARP request containing 1113 * the virtual router MAC address for each IP address 1114 * associated with the virtual router. 1115 */ 1116 static void 1117 carp_send_arp(struct carp_softc *sc) 1118 { 1119 struct ifaddr *ifa; 1120 struct in_addr addr; 1121 1122 CARP_FOREACH_IFA(sc, ifa) { 1123 if (ifa->ifa_addr->sa_family != AF_INET) 1124 continue; 1125 addr = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr; 1126 arp_announce_ifaddr(sc->sc_carpdev, addr, LLADDR(&sc->sc_addr)); 1127 } 1128 } 1129 1130 int 1131 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr) 1132 { 1133 struct carp_softc *sc = ifa->ifa_carp; 1134 1135 if (sc->sc_state == MASTER) { 1136 *enaddr = LLADDR(&sc->sc_addr); 1137 return (1); 1138 } 1139 1140 return (0); 1141 } 1142 #endif 1143 1144 #ifdef INET6 1145 static void 1146 carp_send_na(struct carp_softc *sc) 1147 { 1148 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT; 1149 struct ifaddr *ifa; 1150 struct in6_addr *in6; 1151 1152 CARP_FOREACH_IFA(sc, ifa) { 1153 if (ifa->ifa_addr->sa_family != AF_INET6) 1154 continue; 1155 1156 in6 = IFA_IN6(ifa); 1157 nd6_na_output(sc->sc_carpdev, &mcast, in6, 1158 ND_NA_FLAG_OVERRIDE, 1, NULL); 1159 DELAY(1000); /* XXX */ 1160 } 1161 } 1162 1163 /* 1164 * Returns ifa in case it's a carp address and it is MASTER, or if the address 1165 * matches and is not a carp address. Returns NULL otherwise. 1166 */ 1167 struct ifaddr * 1168 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr) 1169 { 1170 struct ifaddr *ifa; 1171 1172 ifa = NULL; 1173 IF_ADDR_RLOCK(ifp); 1174 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1175 if (ifa->ifa_addr->sa_family != AF_INET6) 1176 continue; 1177 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) 1178 continue; 1179 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER) 1180 ifa = NULL; 1181 else 1182 ifa_ref(ifa); 1183 break; 1184 } 1185 IF_ADDR_RUNLOCK(ifp); 1186 1187 return (ifa); 1188 } 1189 1190 caddr_t 1191 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr) 1192 { 1193 struct ifaddr *ifa; 1194 1195 IF_ADDR_RLOCK(ifp); 1196 IFNET_FOREACH_IFA(ifp, ifa) 1197 if (ifa->ifa_addr->sa_family == AF_INET6 && 1198 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) { 1199 struct carp_softc *sc = ifa->ifa_carp; 1200 struct m_tag *mtag; 1201 1202 IF_ADDR_RUNLOCK(ifp); 1203 1204 mtag = m_tag_get(PACKET_TAG_CARP, 1205 sizeof(struct carp_softc *), M_NOWAIT); 1206 if (mtag == NULL) 1207 /* Better a bit than nothing. */ 1208 return (LLADDR(&sc->sc_addr)); 1209 1210 bcopy(&sc, mtag + 1, sizeof(sc)); 1211 m_tag_prepend(m, mtag); 1212 1213 return (LLADDR(&sc->sc_addr)); 1214 } 1215 IF_ADDR_RUNLOCK(ifp); 1216 1217 return (NULL); 1218 } 1219 #endif /* INET6 */ 1220 1221 int 1222 carp_forus(struct ifnet *ifp, u_char *dhost) 1223 { 1224 struct carp_softc *sc; 1225 uint8_t *ena = dhost; 1226 1227 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1) 1228 return (0); 1229 1230 CIF_LOCK(ifp->if_carp); 1231 IFNET_FOREACH_CARP(ifp, sc) { 1232 CARP_LOCK(sc); 1233 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr), 1234 ETHER_ADDR_LEN)) { 1235 CARP_UNLOCK(sc); 1236 CIF_UNLOCK(ifp->if_carp); 1237 return (1); 1238 } 1239 CARP_UNLOCK(sc); 1240 } 1241 CIF_UNLOCK(ifp->if_carp); 1242 1243 return (0); 1244 } 1245 1246 /* Master down timeout event, executed in callout context. */ 1247 static void 1248 carp_master_down(void *v) 1249 { 1250 struct carp_softc *sc = v; 1251 1252 CARP_LOCK_ASSERT(sc); 1253 1254 CURVNET_SET(sc->sc_carpdev->if_vnet); 1255 if (sc->sc_state == BACKUP) { 1256 carp_master_down_locked(sc, "master timed out"); 1257 } 1258 CURVNET_RESTORE(); 1259 1260 CARP_UNLOCK(sc); 1261 } 1262 1263 static void 1264 carp_master_down_locked(struct carp_softc *sc, const char *reason) 1265 { 1266 1267 CARP_LOCK_ASSERT(sc); 1268 1269 switch (sc->sc_state) { 1270 case BACKUP: 1271 carp_set_state(sc, MASTER, reason); 1272 carp_send_ad_locked(sc); 1273 #ifdef INET 1274 carp_send_arp(sc); 1275 #endif 1276 #ifdef INET6 1277 carp_send_na(sc); 1278 #endif 1279 carp_setrun(sc, 0); 1280 carp_addroute(sc); 1281 break; 1282 case INIT: 1283 case MASTER: 1284 #ifdef INVARIANTS 1285 panic("carp: VHID %u@%s: master_down event in %s state\n", 1286 sc->sc_vhid, 1287 sc->sc_carpdev->if_xname, 1288 sc->sc_state ? "MASTER" : "INIT"); 1289 #endif 1290 break; 1291 } 1292 } 1293 1294 /* 1295 * When in backup state, af indicates whether to reset the master down timer 1296 * for v4 or v6. If it's set to zero, reset the ones which are already pending. 1297 */ 1298 static void 1299 carp_setrun(struct carp_softc *sc, sa_family_t af) 1300 { 1301 struct timeval tv; 1302 1303 CARP_LOCK_ASSERT(sc); 1304 1305 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 || 1306 sc->sc_carpdev->if_link_state != LINK_STATE_UP || 1307 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) || 1308 !V_carp_allow) 1309 return; 1310 1311 switch (sc->sc_state) { 1312 case INIT: 1313 carp_set_state(sc, BACKUP, "initialization complete"); 1314 carp_setrun(sc, 0); 1315 break; 1316 case BACKUP: 1317 callout_stop(&sc->sc_ad_tmo); 1318 tv.tv_sec = 3 * sc->sc_advbase; 1319 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1320 switch (af) { 1321 #ifdef INET 1322 case AF_INET: 1323 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1324 carp_master_down, sc); 1325 break; 1326 #endif 1327 #ifdef INET6 1328 case AF_INET6: 1329 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1330 carp_master_down, sc); 1331 break; 1332 #endif 1333 default: 1334 #ifdef INET 1335 if (sc->sc_naddrs) 1336 callout_reset(&sc->sc_md_tmo, tvtohz(&tv), 1337 carp_master_down, sc); 1338 #endif 1339 #ifdef INET6 1340 if (sc->sc_naddrs6) 1341 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv), 1342 carp_master_down, sc); 1343 #endif 1344 break; 1345 } 1346 break; 1347 case MASTER: 1348 tv.tv_sec = sc->sc_advbase; 1349 tv.tv_usec = sc->sc_advskew * 1000000 / 256; 1350 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), 1351 carp_send_ad, sc); 1352 break; 1353 } 1354 } 1355 1356 /* 1357 * Setup multicast structures. 1358 */ 1359 static int 1360 carp_multicast_setup(struct carp_if *cif, sa_family_t sa) 1361 { 1362 struct ifnet *ifp = cif->cif_ifp; 1363 int error = 0; 1364 1365 switch (sa) { 1366 #ifdef INET 1367 case AF_INET: 1368 { 1369 struct ip_moptions *imo = &cif->cif_imo; 1370 struct in_addr addr; 1371 1372 if (imo->imo_membership) 1373 return (0); 1374 1375 imo->imo_membership = (struct in_multi **)malloc( 1376 (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP, 1377 M_WAITOK); 1378 imo->imo_mfilters = NULL; 1379 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS; 1380 imo->imo_multicast_vif = -1; 1381 1382 addr.s_addr = htonl(INADDR_CARP_GROUP); 1383 if ((error = in_joingroup(ifp, &addr, NULL, 1384 &imo->imo_membership[0])) != 0) { 1385 free(imo->imo_membership, M_CARP); 1386 break; 1387 } 1388 imo->imo_num_memberships++; 1389 imo->imo_multicast_ifp = ifp; 1390 imo->imo_multicast_ttl = CARP_DFLTTL; 1391 imo->imo_multicast_loop = 0; 1392 break; 1393 } 1394 #endif 1395 #ifdef INET6 1396 case AF_INET6: 1397 { 1398 struct ip6_moptions *im6o = &cif->cif_im6o; 1399 struct in6_addr in6; 1400 struct in6_multi *in6m; 1401 1402 if (im6o->im6o_membership) 1403 return (0); 1404 1405 im6o->im6o_membership = (struct in6_multi **)malloc( 1406 (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP, 1407 M_ZERO | M_WAITOK); 1408 im6o->im6o_mfilters = NULL; 1409 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS; 1410 im6o->im6o_multicast_hlim = CARP_DFLTTL; 1411 im6o->im6o_multicast_ifp = ifp; 1412 1413 /* Join IPv6 CARP multicast group. */ 1414 bzero(&in6, sizeof(in6)); 1415 in6.s6_addr16[0] = htons(0xff02); 1416 in6.s6_addr8[15] = 0x12; 1417 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1418 free(im6o->im6o_membership, M_CARP); 1419 break; 1420 } 1421 in6m = NULL; 1422 if ((error = in6_joingroup(ifp, &in6, NULL, &in6m, 0)) != 0) { 1423 free(im6o->im6o_membership, M_CARP); 1424 break; 1425 } 1426 in6m_acquire(in6m); 1427 im6o->im6o_membership[0] = in6m; 1428 im6o->im6o_num_memberships++; 1429 1430 /* Join solicited multicast address. */ 1431 bzero(&in6, sizeof(in6)); 1432 in6.s6_addr16[0] = htons(0xff02); 1433 in6.s6_addr32[1] = 0; 1434 in6.s6_addr32[2] = htonl(1); 1435 in6.s6_addr32[3] = 0; 1436 in6.s6_addr8[12] = 0xff; 1437 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) { 1438 in6_leavegroup(im6o->im6o_membership[0], NULL); 1439 free(im6o->im6o_membership, M_CARP); 1440 break; 1441 } 1442 in6m = NULL; 1443 if ((error = in6_joingroup(ifp, &in6, NULL, &in6m, 0)) != 0) { 1444 in6_leavegroup(im6o->im6o_membership[0], NULL); 1445 free(im6o->im6o_membership, M_CARP); 1446 break; 1447 } 1448 in6m_acquire(in6m); 1449 im6o->im6o_membership[1] = in6m; 1450 im6o->im6o_num_memberships++; 1451 break; 1452 } 1453 #endif 1454 } 1455 1456 return (error); 1457 } 1458 1459 /* 1460 * Free multicast structures. 1461 */ 1462 static void 1463 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa) 1464 { 1465 1466 sx_assert(&carp_sx, SA_XLOCKED); 1467 1468 switch (sa) { 1469 #ifdef INET 1470 case AF_INET: 1471 if (cif->cif_naddrs == 0) { 1472 struct ip_moptions *imo = &cif->cif_imo; 1473 1474 in_leavegroup(imo->imo_membership[0], NULL); 1475 KASSERT(imo->imo_mfilters == NULL, 1476 ("%s: imo_mfilters != NULL", __func__)); 1477 free(imo->imo_membership, M_CARP); 1478 imo->imo_membership = NULL; 1479 1480 } 1481 break; 1482 #endif 1483 #ifdef INET6 1484 case AF_INET6: 1485 if (cif->cif_naddrs6 == 0) { 1486 struct ip6_moptions *im6o = &cif->cif_im6o; 1487 1488 in6_leavegroup(im6o->im6o_membership[0], NULL); 1489 in6_leavegroup(im6o->im6o_membership[1], NULL); 1490 KASSERT(im6o->im6o_mfilters == NULL, 1491 ("%s: im6o_mfilters != NULL", __func__)); 1492 free(im6o->im6o_membership, M_CARP); 1493 im6o->im6o_membership = NULL; 1494 } 1495 break; 1496 #endif 1497 } 1498 } 1499 1500 int 1501 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa) 1502 { 1503 struct m_tag *mtag; 1504 struct carp_softc *sc; 1505 1506 if (!sa) 1507 return (0); 1508 1509 switch (sa->sa_family) { 1510 #ifdef INET 1511 case AF_INET: 1512 break; 1513 #endif 1514 #ifdef INET6 1515 case AF_INET6: 1516 break; 1517 #endif 1518 default: 1519 return (0); 1520 } 1521 1522 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL); 1523 if (mtag == NULL) 1524 return (0); 1525 1526 bcopy(mtag + 1, &sc, sizeof(sc)); 1527 1528 /* Set the source MAC address to the Virtual Router MAC Address. */ 1529 switch (ifp->if_type) { 1530 case IFT_ETHER: 1531 case IFT_BRIDGE: 1532 case IFT_L2VLAN: { 1533 struct ether_header *eh; 1534 1535 eh = mtod(m, struct ether_header *); 1536 eh->ether_shost[0] = 0; 1537 eh->ether_shost[1] = 0; 1538 eh->ether_shost[2] = 0x5e; 1539 eh->ether_shost[3] = 0; 1540 eh->ether_shost[4] = 1; 1541 eh->ether_shost[5] = sc->sc_vhid; 1542 } 1543 break; 1544 default: 1545 printf("%s: carp is not supported for the %d interface type\n", 1546 ifp->if_xname, ifp->if_type); 1547 return (EOPNOTSUPP); 1548 } 1549 1550 return (0); 1551 } 1552 1553 static struct carp_softc* 1554 carp_alloc(struct ifnet *ifp) 1555 { 1556 struct carp_softc *sc; 1557 struct carp_if *cif; 1558 1559 sx_assert(&carp_sx, SA_XLOCKED); 1560 1561 if ((cif = ifp->if_carp) == NULL) 1562 cif = carp_alloc_if(ifp); 1563 1564 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO); 1565 1566 sc->sc_advbase = CARP_DFLTINTV; 1567 sc->sc_vhid = -1; /* required setting */ 1568 sc->sc_init_counter = 1; 1569 sc->sc_state = INIT; 1570 1571 sc->sc_ifasiz = sizeof(struct ifaddr *); 1572 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO); 1573 sc->sc_carpdev = ifp; 1574 1575 CARP_LOCK_INIT(sc); 1576 #ifdef INET 1577 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1578 #endif 1579 #ifdef INET6 1580 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1581 #endif 1582 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED); 1583 1584 CIF_LOCK(cif); 1585 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list); 1586 CIF_UNLOCK(cif); 1587 1588 mtx_lock(&carp_mtx); 1589 LIST_INSERT_HEAD(&carp_list, sc, sc_next); 1590 mtx_unlock(&carp_mtx); 1591 1592 return (sc); 1593 } 1594 1595 static void 1596 carp_grow_ifas(struct carp_softc *sc) 1597 { 1598 struct ifaddr **new; 1599 1600 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_WAITOK | M_ZERO); 1601 CARP_LOCK(sc); 1602 bcopy(sc->sc_ifas, new, sc->sc_ifasiz); 1603 free(sc->sc_ifas, M_CARP); 1604 sc->sc_ifas = new; 1605 sc->sc_ifasiz *= 2; 1606 CARP_UNLOCK(sc); 1607 } 1608 1609 static void 1610 carp_destroy(struct carp_softc *sc) 1611 { 1612 struct ifnet *ifp = sc->sc_carpdev; 1613 struct carp_if *cif = ifp->if_carp; 1614 1615 sx_assert(&carp_sx, SA_XLOCKED); 1616 1617 if (sc->sc_suppress) 1618 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed"); 1619 CARP_UNLOCK(sc); 1620 1621 CIF_LOCK(cif); 1622 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list); 1623 CIF_UNLOCK(cif); 1624 1625 mtx_lock(&carp_mtx); 1626 LIST_REMOVE(sc, sc_next); 1627 mtx_unlock(&carp_mtx); 1628 1629 callout_drain(&sc->sc_ad_tmo); 1630 #ifdef INET 1631 callout_drain(&sc->sc_md_tmo); 1632 #endif 1633 #ifdef INET6 1634 callout_drain(&sc->sc_md6_tmo); 1635 #endif 1636 CARP_LOCK_DESTROY(sc); 1637 1638 free(sc->sc_ifas, M_CARP); 1639 free(sc, M_CARP); 1640 } 1641 1642 static struct carp_if* 1643 carp_alloc_if(struct ifnet *ifp) 1644 { 1645 struct carp_if *cif; 1646 int error; 1647 1648 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO); 1649 1650 if ((error = ifpromisc(ifp, 1)) != 0) 1651 printf("%s: ifpromisc(%s) failed: %d\n", 1652 __func__, ifp->if_xname, error); 1653 else 1654 cif->cif_flags |= CIF_PROMISC; 1655 1656 CIF_LOCK_INIT(cif); 1657 cif->cif_ifp = ifp; 1658 TAILQ_INIT(&cif->cif_vrs); 1659 1660 IF_ADDR_WLOCK(ifp); 1661 ifp->if_carp = cif; 1662 if_ref(ifp); 1663 IF_ADDR_WUNLOCK(ifp); 1664 1665 return (cif); 1666 } 1667 1668 static void 1669 carp_free_if(struct carp_if *cif) 1670 { 1671 struct ifnet *ifp = cif->cif_ifp; 1672 1673 CIF_LOCK_ASSERT(cif); 1674 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty", 1675 __func__)); 1676 1677 IF_ADDR_WLOCK(ifp); 1678 ifp->if_carp = NULL; 1679 IF_ADDR_WUNLOCK(ifp); 1680 1681 CIF_LOCK_DESTROY(cif); 1682 1683 if (cif->cif_flags & CIF_PROMISC) 1684 ifpromisc(ifp, 0); 1685 if_rele(ifp); 1686 1687 free(cif, M_CARP); 1688 } 1689 1690 static void 1691 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv) 1692 { 1693 1694 CARP_LOCK(sc); 1695 carpr->carpr_state = sc->sc_state; 1696 carpr->carpr_vhid = sc->sc_vhid; 1697 carpr->carpr_advbase = sc->sc_advbase; 1698 carpr->carpr_advskew = sc->sc_advskew; 1699 if (priv) 1700 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key)); 1701 else 1702 bzero(carpr->carpr_key, sizeof(carpr->carpr_key)); 1703 CARP_UNLOCK(sc); 1704 } 1705 1706 int 1707 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td) 1708 { 1709 struct carpreq carpr; 1710 struct ifnet *ifp; 1711 struct carp_softc *sc = NULL; 1712 int error = 0, locked = 0; 1713 1714 if ((error = copyin(ifr_data_get_ptr(ifr), &carpr, sizeof carpr))) 1715 return (error); 1716 1717 ifp = ifunit_ref(ifr->ifr_name); 1718 if (ifp == NULL) 1719 return (ENXIO); 1720 1721 switch (ifp->if_type) { 1722 case IFT_ETHER: 1723 case IFT_L2VLAN: 1724 case IFT_BRIDGE: 1725 break; 1726 default: 1727 error = EOPNOTSUPP; 1728 goto out; 1729 } 1730 1731 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 1732 error = EADDRNOTAVAIL; 1733 goto out; 1734 } 1735 1736 sx_xlock(&carp_sx); 1737 switch (cmd) { 1738 case SIOCSVH: 1739 if ((error = priv_check(td, PRIV_NETINET_CARP))) 1740 break; 1741 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID || 1742 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) { 1743 error = EINVAL; 1744 break; 1745 } 1746 1747 if (ifp->if_carp) { 1748 IFNET_FOREACH_CARP(ifp, sc) 1749 if (sc->sc_vhid == carpr.carpr_vhid) 1750 break; 1751 } 1752 if (sc == NULL) { 1753 sc = carp_alloc(ifp); 1754 CARP_LOCK(sc); 1755 sc->sc_vhid = carpr.carpr_vhid; 1756 LLADDR(&sc->sc_addr)[0] = 0; 1757 LLADDR(&sc->sc_addr)[1] = 0; 1758 LLADDR(&sc->sc_addr)[2] = 0x5e; 1759 LLADDR(&sc->sc_addr)[3] = 0; 1760 LLADDR(&sc->sc_addr)[4] = 1; 1761 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid; 1762 } else 1763 CARP_LOCK(sc); 1764 locked = 1; 1765 if (carpr.carpr_advbase > 0) { 1766 if (carpr.carpr_advbase > 255 || 1767 carpr.carpr_advbase < CARP_DFLTINTV) { 1768 error = EINVAL; 1769 break; 1770 } 1771 sc->sc_advbase = carpr.carpr_advbase; 1772 } 1773 if (carpr.carpr_advskew >= 255) { 1774 error = EINVAL; 1775 break; 1776 } 1777 sc->sc_advskew = carpr.carpr_advskew; 1778 if (carpr.carpr_key[0] != '\0') { 1779 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key)); 1780 carp_hmac_prepare(sc); 1781 } 1782 if (sc->sc_state != INIT && 1783 carpr.carpr_state != sc->sc_state) { 1784 switch (carpr.carpr_state) { 1785 case BACKUP: 1786 callout_stop(&sc->sc_ad_tmo); 1787 carp_set_state(sc, BACKUP, 1788 "user requested via ifconfig"); 1789 carp_setrun(sc, 0); 1790 carp_delroute(sc); 1791 break; 1792 case MASTER: 1793 carp_master_down_locked(sc, 1794 "user requested via ifconfig"); 1795 break; 1796 default: 1797 break; 1798 } 1799 } 1800 break; 1801 1802 case SIOCGVH: 1803 { 1804 int priveleged; 1805 1806 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) { 1807 error = EINVAL; 1808 break; 1809 } 1810 if (carpr.carpr_count < 1) { 1811 error = EMSGSIZE; 1812 break; 1813 } 1814 if (ifp->if_carp == NULL) { 1815 error = ENOENT; 1816 break; 1817 } 1818 1819 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0); 1820 if (carpr.carpr_vhid != 0) { 1821 IFNET_FOREACH_CARP(ifp, sc) 1822 if (sc->sc_vhid == carpr.carpr_vhid) 1823 break; 1824 if (sc == NULL) { 1825 error = ENOENT; 1826 break; 1827 } 1828 carp_carprcp(&carpr, sc, priveleged); 1829 error = copyout(&carpr, ifr_data_get_ptr(ifr), 1830 sizeof(carpr)); 1831 } else { 1832 int i, count; 1833 1834 count = 0; 1835 IFNET_FOREACH_CARP(ifp, sc) 1836 count++; 1837 1838 if (count > carpr.carpr_count) { 1839 CIF_UNLOCK(ifp->if_carp); 1840 error = EMSGSIZE; 1841 break; 1842 } 1843 1844 i = 0; 1845 IFNET_FOREACH_CARP(ifp, sc) { 1846 carp_carprcp(&carpr, sc, priveleged); 1847 carpr.carpr_count = count; 1848 error = copyout(&carpr, 1849 (caddr_t)ifr_data_get_ptr(ifr) + 1850 (i * sizeof(carpr)), sizeof(carpr)); 1851 if (error) { 1852 CIF_UNLOCK(ifp->if_carp); 1853 break; 1854 } 1855 i++; 1856 } 1857 } 1858 break; 1859 } 1860 default: 1861 error = EINVAL; 1862 } 1863 sx_xunlock(&carp_sx); 1864 1865 out: 1866 if (locked) 1867 CARP_UNLOCK(sc); 1868 if_rele(ifp); 1869 1870 return (error); 1871 } 1872 1873 static int 1874 carp_get_vhid(struct ifaddr *ifa) 1875 { 1876 1877 if (ifa == NULL || ifa->ifa_carp == NULL) 1878 return (0); 1879 1880 return (ifa->ifa_carp->sc_vhid); 1881 } 1882 1883 int 1884 carp_attach(struct ifaddr *ifa, int vhid) 1885 { 1886 struct ifnet *ifp = ifa->ifa_ifp; 1887 struct carp_if *cif = ifp->if_carp; 1888 struct carp_softc *sc; 1889 int index, error; 1890 1891 KASSERT(ifa->ifa_carp == NULL, ("%s: ifa %p attached", __func__, ifa)); 1892 1893 switch (ifa->ifa_addr->sa_family) { 1894 #ifdef INET 1895 case AF_INET: 1896 #endif 1897 #ifdef INET6 1898 case AF_INET6: 1899 #endif 1900 break; 1901 default: 1902 return (EPROTOTYPE); 1903 } 1904 1905 sx_xlock(&carp_sx); 1906 if (ifp->if_carp == NULL) { 1907 sx_xunlock(&carp_sx); 1908 return (ENOPROTOOPT); 1909 } 1910 1911 IFNET_FOREACH_CARP(ifp, sc) 1912 if (sc->sc_vhid == vhid) 1913 break; 1914 if (sc == NULL) { 1915 sx_xunlock(&carp_sx); 1916 return (ENOENT); 1917 } 1918 1919 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family); 1920 if (error) { 1921 CIF_FREE(cif); 1922 sx_xunlock(&carp_sx); 1923 return (error); 1924 } 1925 1926 index = sc->sc_naddrs + sc->sc_naddrs6 + 1; 1927 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *)) 1928 carp_grow_ifas(sc); 1929 1930 switch (ifa->ifa_addr->sa_family) { 1931 #ifdef INET 1932 case AF_INET: 1933 cif->cif_naddrs++; 1934 sc->sc_naddrs++; 1935 break; 1936 #endif 1937 #ifdef INET6 1938 case AF_INET6: 1939 cif->cif_naddrs6++; 1940 sc->sc_naddrs6++; 1941 break; 1942 #endif 1943 } 1944 1945 ifa_ref(ifa); 1946 1947 CARP_LOCK(sc); 1948 sc->sc_ifas[index - 1] = ifa; 1949 ifa->ifa_carp = sc; 1950 carp_hmac_prepare(sc); 1951 carp_sc_state(sc); 1952 CARP_UNLOCK(sc); 1953 1954 sx_xunlock(&carp_sx); 1955 1956 return (0); 1957 } 1958 1959 void 1960 carp_detach(struct ifaddr *ifa, bool keep_cif) 1961 { 1962 struct ifnet *ifp = ifa->ifa_ifp; 1963 struct carp_if *cif = ifp->if_carp; 1964 struct carp_softc *sc = ifa->ifa_carp; 1965 int i, index; 1966 1967 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa)); 1968 1969 sx_xlock(&carp_sx); 1970 1971 CARP_LOCK(sc); 1972 /* Shift array. */ 1973 index = sc->sc_naddrs + sc->sc_naddrs6; 1974 for (i = 0; i < index; i++) 1975 if (sc->sc_ifas[i] == ifa) 1976 break; 1977 KASSERT(i < index, ("%s: %p no backref", __func__, ifa)); 1978 for (; i < index - 1; i++) 1979 sc->sc_ifas[i] = sc->sc_ifas[i+1]; 1980 sc->sc_ifas[index - 1] = NULL; 1981 1982 switch (ifa->ifa_addr->sa_family) { 1983 #ifdef INET 1984 case AF_INET: 1985 cif->cif_naddrs--; 1986 sc->sc_naddrs--; 1987 break; 1988 #endif 1989 #ifdef INET6 1990 case AF_INET6: 1991 cif->cif_naddrs6--; 1992 sc->sc_naddrs6--; 1993 break; 1994 #endif 1995 } 1996 1997 carp_ifa_delroute(ifa); 1998 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family); 1999 2000 ifa->ifa_carp = NULL; 2001 ifa_free(ifa); 2002 2003 carp_hmac_prepare(sc); 2004 carp_sc_state(sc); 2005 2006 if (!keep_cif && sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) 2007 carp_destroy(sc); 2008 else 2009 CARP_UNLOCK(sc); 2010 2011 if (!keep_cif) 2012 CIF_FREE(cif); 2013 2014 sx_xunlock(&carp_sx); 2015 } 2016 2017 static void 2018 carp_set_state(struct carp_softc *sc, int state, const char *reason) 2019 { 2020 2021 CARP_LOCK_ASSERT(sc); 2022 2023 if (sc->sc_state != state) { 2024 const char *carp_states[] = { CARP_STATES }; 2025 char subsys[IFNAMSIZ+5]; 2026 2027 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid, 2028 sc->sc_carpdev->if_xname); 2029 2030 CARP_LOG("%s: %s -> %s (%s)\n", subsys, 2031 carp_states[sc->sc_state], carp_states[state], reason); 2032 2033 sc->sc_state = state; 2034 2035 devctl_notify("CARP", subsys, carp_states[state], NULL); 2036 } 2037 } 2038 2039 static void 2040 carp_linkstate(struct ifnet *ifp) 2041 { 2042 struct carp_softc *sc; 2043 2044 CIF_LOCK(ifp->if_carp); 2045 IFNET_FOREACH_CARP(ifp, sc) { 2046 CARP_LOCK(sc); 2047 carp_sc_state(sc); 2048 CARP_UNLOCK(sc); 2049 } 2050 CIF_UNLOCK(ifp->if_carp); 2051 } 2052 2053 static void 2054 carp_sc_state(struct carp_softc *sc) 2055 { 2056 2057 CARP_LOCK_ASSERT(sc); 2058 2059 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP || 2060 !(sc->sc_carpdev->if_flags & IFF_UP) || 2061 !V_carp_allow) { 2062 callout_stop(&sc->sc_ad_tmo); 2063 #ifdef INET 2064 callout_stop(&sc->sc_md_tmo); 2065 #endif 2066 #ifdef INET6 2067 callout_stop(&sc->sc_md6_tmo); 2068 #endif 2069 carp_set_state(sc, INIT, "hardware interface down"); 2070 carp_setrun(sc, 0); 2071 if (!sc->sc_suppress) 2072 carp_demote_adj(V_carp_ifdown_adj, "interface down"); 2073 sc->sc_suppress = 1; 2074 } else { 2075 carp_set_state(sc, INIT, "hardware interface up"); 2076 carp_setrun(sc, 0); 2077 if (sc->sc_suppress) 2078 carp_demote_adj(-V_carp_ifdown_adj, "interface up"); 2079 sc->sc_suppress = 0; 2080 } 2081 } 2082 2083 static void 2084 carp_demote_adj(int adj, char *reason) 2085 { 2086 atomic_add_int(&V_carp_demotion, adj); 2087 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason); 2088 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task); 2089 } 2090 2091 static int 2092 carp_allow_sysctl(SYSCTL_HANDLER_ARGS) 2093 { 2094 int new, error; 2095 struct carp_softc *sc; 2096 2097 new = V_carp_allow; 2098 error = sysctl_handle_int(oidp, &new, 0, req); 2099 if (error || !req->newptr) 2100 return (error); 2101 2102 if (V_carp_allow != new) { 2103 V_carp_allow = new; 2104 2105 mtx_lock(&carp_mtx); 2106 LIST_FOREACH(sc, &carp_list, sc_next) { 2107 CARP_LOCK(sc); 2108 if (curvnet == sc->sc_carpdev->if_vnet) 2109 carp_sc_state(sc); 2110 CARP_UNLOCK(sc); 2111 } 2112 mtx_unlock(&carp_mtx); 2113 } 2114 2115 return (0); 2116 } 2117 2118 static int 2119 carp_dscp_sysctl(SYSCTL_HANDLER_ARGS) 2120 { 2121 int new, error; 2122 2123 new = V_carp_dscp; 2124 error = sysctl_handle_int(oidp, &new, 0, req); 2125 if (error || !req->newptr) 2126 return (error); 2127 2128 if (new < 0 || new > 63) 2129 return (EINVAL); 2130 2131 V_carp_dscp = new; 2132 2133 return (0); 2134 } 2135 2136 static int 2137 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS) 2138 { 2139 int new, error; 2140 2141 new = V_carp_demotion; 2142 error = sysctl_handle_int(oidp, &new, 0, req); 2143 if (error || !req->newptr) 2144 return (error); 2145 2146 carp_demote_adj(new, "sysctl"); 2147 2148 return (0); 2149 } 2150 2151 #ifdef INET 2152 extern struct domain inetdomain; 2153 static struct protosw in_carp_protosw = { 2154 .pr_type = SOCK_RAW, 2155 .pr_domain = &inetdomain, 2156 .pr_protocol = IPPROTO_CARP, 2157 .pr_flags = PR_ATOMIC|PR_ADDR, 2158 .pr_input = carp_input, 2159 .pr_output = rip_output, 2160 .pr_ctloutput = rip_ctloutput, 2161 .pr_usrreqs = &rip_usrreqs 2162 }; 2163 #endif 2164 2165 #ifdef INET6 2166 extern struct domain inet6domain; 2167 static struct protosw in6_carp_protosw = { 2168 .pr_type = SOCK_RAW, 2169 .pr_domain = &inet6domain, 2170 .pr_protocol = IPPROTO_CARP, 2171 .pr_flags = PR_ATOMIC|PR_ADDR, 2172 .pr_input = carp6_input, 2173 .pr_output = rip6_output, 2174 .pr_ctloutput = rip6_ctloutput, 2175 .pr_usrreqs = &rip6_usrreqs 2176 }; 2177 #endif 2178 2179 #ifdef VIMAGE 2180 #if defined(__i386__) 2181 /* 2182 * XXX This is a hack to work around an absolute relocation outside 2183 * set_vnet by one (on the stop symbol) for carpstats. Add a dummy variable 2184 * to the end of the file in the hope that the linker will just keep the 2185 * order (as it seems to do at the moment). It is understood to be fragile. 2186 * See PR 230857 for a longer discussion of the problem and the referenced 2187 * review for possible alternate solutions. Each is a hack; we just need 2188 * the least intrusive one for the next release. 2189 */ 2190 VNET_DEFINE(char, carp_zzz) = 0xde; 2191 #endif 2192 #endif 2193 2194 static void 2195 carp_mod_cleanup(void) 2196 { 2197 2198 #ifdef INET 2199 if (proto_reg[CARP_INET] == 0) { 2200 (void)ipproto_unregister(IPPROTO_CARP); 2201 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW); 2202 proto_reg[CARP_INET] = -1; 2203 } 2204 carp_iamatch_p = NULL; 2205 #endif 2206 #ifdef INET6 2207 if (proto_reg[CARP_INET6] == 0) { 2208 (void)ip6proto_unregister(IPPROTO_CARP); 2209 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW); 2210 proto_reg[CARP_INET6] = -1; 2211 } 2212 carp_iamatch6_p = NULL; 2213 carp_macmatch6_p = NULL; 2214 #endif 2215 carp_ioctl_p = NULL; 2216 carp_attach_p = NULL; 2217 carp_detach_p = NULL; 2218 carp_get_vhid_p = NULL; 2219 carp_linkstate_p = NULL; 2220 carp_forus_p = NULL; 2221 carp_output_p = NULL; 2222 carp_demote_adj_p = NULL; 2223 carp_master_p = NULL; 2224 mtx_unlock(&carp_mtx); 2225 taskqueue_drain(taskqueue_swi, &carp_sendall_task); 2226 mtx_destroy(&carp_mtx); 2227 sx_destroy(&carp_sx); 2228 } 2229 2230 static int 2231 carp_mod_load(void) 2232 { 2233 int err; 2234 2235 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF); 2236 sx_init(&carp_sx, "carp_sx"); 2237 LIST_INIT(&carp_list); 2238 carp_get_vhid_p = carp_get_vhid; 2239 carp_forus_p = carp_forus; 2240 carp_output_p = carp_output; 2241 carp_linkstate_p = carp_linkstate; 2242 carp_ioctl_p = carp_ioctl; 2243 carp_attach_p = carp_attach; 2244 carp_detach_p = carp_detach; 2245 carp_demote_adj_p = carp_demote_adj; 2246 carp_master_p = carp_master; 2247 #ifdef INET6 2248 carp_iamatch6_p = carp_iamatch6; 2249 carp_macmatch6_p = carp_macmatch6; 2250 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6, 2251 (struct protosw *)&in6_carp_protosw); 2252 if (proto_reg[CARP_INET6]) { 2253 printf("carp: error %d attaching to PF_INET6\n", 2254 proto_reg[CARP_INET6]); 2255 carp_mod_cleanup(); 2256 return (proto_reg[CARP_INET6]); 2257 } 2258 err = ip6proto_register(IPPROTO_CARP); 2259 if (err) { 2260 printf("carp: error %d registering with INET6\n", err); 2261 carp_mod_cleanup(); 2262 return (err); 2263 } 2264 #endif 2265 #ifdef INET 2266 carp_iamatch_p = carp_iamatch; 2267 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw); 2268 if (proto_reg[CARP_INET]) { 2269 printf("carp: error %d attaching to PF_INET\n", 2270 proto_reg[CARP_INET]); 2271 carp_mod_cleanup(); 2272 return (proto_reg[CARP_INET]); 2273 } 2274 err = ipproto_register(IPPROTO_CARP); 2275 if (err) { 2276 printf("carp: error %d registering with INET\n", err); 2277 carp_mod_cleanup(); 2278 return (err); 2279 } 2280 #endif 2281 return (0); 2282 } 2283 2284 static int 2285 carp_modevent(module_t mod, int type, void *data) 2286 { 2287 switch (type) { 2288 case MOD_LOAD: 2289 return carp_mod_load(); 2290 /* NOTREACHED */ 2291 case MOD_UNLOAD: 2292 mtx_lock(&carp_mtx); 2293 if (LIST_EMPTY(&carp_list)) 2294 carp_mod_cleanup(); 2295 else { 2296 mtx_unlock(&carp_mtx); 2297 return (EBUSY); 2298 } 2299 break; 2300 2301 default: 2302 return (EINVAL); 2303 } 2304 2305 return (0); 2306 } 2307 2308 static moduledata_t carp_mod = { 2309 "carp", 2310 carp_modevent, 2311 0 2312 }; 2313 2314 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);
Cache object: 5cf44408148903e3cf0f70e49355d7bd
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]