1 /*-
2 * Copyright (c) 2002 Michael Shalayeff.
3 * Copyright (c) 2003 Ryan McBride.
4 * Copyright (c) 2011 Gleb Smirnoff <glebius@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
25 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
26 * THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: stable/10/sys/netinet/ip_carp.c 278075 2015-02-02 11:42:35Z loos $");
31
32 #include "opt_bpf.h"
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/jail.h>
40 #include <sys/kernel.h>
41 #include <sys/limits.h>
42 #include <sys/malloc.h>
43 #include <sys/mbuf.h>
44 #include <sys/module.h>
45 #include <sys/priv.h>
46 #include <sys/proc.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/sockio.h>
50 #include <sys/sysctl.h>
51 #include <sys/syslog.h>
52 #include <sys/taskqueue.h>
53 #include <sys/counter.h>
54
55 #include <net/ethernet.h>
56 #include <net/fddi.h>
57 #include <net/if.h>
58 #include <net/if_dl.h>
59 #include <net/if_llatbl.h>
60 #include <net/if_types.h>
61 #include <net/iso88025.h>
62 #include <net/route.h>
63 #include <net/vnet.h>
64
65 #if defined(INET) || defined(INET6)
66 #include <netinet/in.h>
67 #include <netinet/in_var.h>
68 #include <netinet/ip_carp.h>
69 #include <netinet/ip.h>
70 #include <machine/in_cksum.h>
71 #endif
72 #ifdef INET
73 #include <netinet/ip_var.h>
74 #include <netinet/if_ether.h>
75 #endif
76
77 #ifdef INET6
78 #include <netinet/icmp6.h>
79 #include <netinet/ip6.h>
80 #include <netinet6/ip6protosw.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 };
148
149 #define CARP_INET 0
150 #define CARP_INET6 1
151 static int proto_reg[] = {-1, -1};
152
153 /*
154 * Brief design of carp(4).
155 *
156 * Any carp-capable ifnet may have a list of carp softcs hanging off
157 * its ifp->if_carp pointer. Each softc represents one unique virtual
158 * host id, or vhid. The softc has a back pointer to the ifnet. All
159 * softcs are joined in a global list, which has quite limited use.
160 *
161 * Any interface address that takes part in CARP negotiation has a
162 * pointer to the softc of its vhid, ifa->ifa_carp. That could be either
163 * AF_INET or AF_INET6 address.
164 *
165 * Although, one can get the softc's backpointer to ifnet and traverse
166 * through its ifp->if_addrhead queue to find all interface addresses
167 * involved in CARP, we keep a growable array of ifaddr pointers. This
168 * allows us to avoid grabbing the IF_ADDR_LOCK() in many traversals that
169 * do calls into the network stack, thus avoiding LORs.
170 *
171 * Locking:
172 *
173 * Each softc has a lock sc_mtx. It is used to synchronise carp_input_c(),
174 * callout-driven events and ioctl()s.
175 *
176 * To traverse the list of softcs on an ifnet we use CIF_LOCK(), to
177 * traverse the global list we use the mutex carp_mtx.
178 *
179 * Known issues with locking:
180 *
181 * - There is no protection for races between two ioctl() requests,
182 * neither SIOCSVH, nor SIOCAIFADDR & SIOCAIFADDR_IN6. I think that all
183 * interface ioctl()s should be serialized right in net/if.c.
184 * - Sending ad, we put the pointer to the softc in an mtag, and no reference
185 * counting is done on the softc.
186 * - On module unload we may race (?) with packet processing thread
187 * dereferencing our function pointers.
188 */
189
190 /* Accept incoming CARP packets. */
191 static VNET_DEFINE(int, carp_allow) = 1;
192 #define V_carp_allow VNET(carp_allow)
193
194 /* Preempt slower nodes. */
195 static VNET_DEFINE(int, carp_preempt) = 0;
196 #define V_carp_preempt VNET(carp_preempt)
197
198 /* Log level. */
199 static VNET_DEFINE(int, carp_log) = 1;
200 #define V_carp_log VNET(carp_log)
201
202 /* Global advskew demotion. */
203 static VNET_DEFINE(int, carp_demotion) = 0;
204 #define V_carp_demotion VNET(carp_demotion)
205
206 /* Send error demotion factor. */
207 static VNET_DEFINE(int, carp_senderr_adj) = CARP_MAXSKEW;
208 #define V_carp_senderr_adj VNET(carp_senderr_adj)
209
210 /* Iface down demotion factor. */
211 static VNET_DEFINE(int, carp_ifdown_adj) = CARP_MAXSKEW;
212 #define V_carp_ifdown_adj VNET(carp_ifdown_adj)
213
214 static int carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS);
215
216 SYSCTL_NODE(_net_inet, IPPROTO_CARP, carp, CTLFLAG_RW, 0, "CARP");
217 SYSCTL_VNET_INT(_net_inet_carp, OID_AUTO, allow, CTLFLAG_RW,
218 &VNET_NAME(carp_allow), 0, "Accept incoming CARP packets");
219 SYSCTL_VNET_INT(_net_inet_carp, OID_AUTO, preempt, CTLFLAG_RW,
220 &VNET_NAME(carp_preempt), 0, "High-priority backup preemption mode");
221 SYSCTL_VNET_INT(_net_inet_carp, OID_AUTO, log, CTLFLAG_RW,
222 &VNET_NAME(carp_log), 0, "CARP log level");
223 SYSCTL_VNET_PROC(_net_inet_carp, OID_AUTO, demotion, CTLTYPE_INT|CTLFLAG_RW,
224 0, 0, carp_demote_adj_sysctl, "I",
225 "Adjust demotion factor (skew of advskew)");
226 SYSCTL_VNET_INT(_net_inet_carp, OID_AUTO, senderr_demotion_factor, CTLFLAG_RW,
227 &VNET_NAME(carp_senderr_adj), 0, "Send error demotion factor adjustment");
228 SYSCTL_VNET_INT(_net_inet_carp, OID_AUTO, ifdown_demotion_factor, CTLFLAG_RW,
229 &VNET_NAME(carp_ifdown_adj), 0,
230 "Interface down demotion factor adjustment");
231
232 VNET_PCPUSTAT_DEFINE(struct carpstats, carpstats);
233 VNET_PCPUSTAT_SYSINIT(carpstats);
234 VNET_PCPUSTAT_SYSUNINIT(carpstats);
235
236 #define CARPSTATS_ADD(name, val) \
237 counter_u64_add(VNET(carpstats)[offsetof(struct carpstats, name) / \
238 sizeof(uint64_t)], (val))
239 #define CARPSTATS_INC(name) CARPSTATS_ADD(name, 1)
240
241 SYSCTL_VNET_PCPUSTAT(_net_inet_carp, OID_AUTO, stats, struct carpstats,
242 carpstats, "CARP statistics (struct carpstats, netinet/ip_carp.h)");
243
244 #define CARP_LOCK_INIT(sc) mtx_init(&(sc)->sc_mtx, "carp_softc", \
245 NULL, MTX_DEF)
246 #define CARP_LOCK_DESTROY(sc) mtx_destroy(&(sc)->sc_mtx)
247 #define CARP_LOCK_ASSERT(sc) mtx_assert(&(sc)->sc_mtx, MA_OWNED)
248 #define CARP_LOCK(sc) mtx_lock(&(sc)->sc_mtx)
249 #define CARP_UNLOCK(sc) mtx_unlock(&(sc)->sc_mtx)
250 #define CIF_LOCK_INIT(cif) mtx_init(&(cif)->cif_mtx, "carp_if", \
251 NULL, MTX_DEF)
252 #define CIF_LOCK_DESTROY(cif) mtx_destroy(&(cif)->cif_mtx)
253 #define CIF_LOCK_ASSERT(cif) mtx_assert(&(cif)->cif_mtx, MA_OWNED)
254 #define CIF_LOCK(cif) mtx_lock(&(cif)->cif_mtx)
255 #define CIF_UNLOCK(cif) mtx_unlock(&(cif)->cif_mtx)
256 #define CIF_FREE(cif) do { \
257 CIF_LOCK_ASSERT(cif); \
258 if (TAILQ_EMPTY(&(cif)->cif_vrs)) \
259 carp_free_if(cif); \
260 else \
261 CIF_UNLOCK(cif); \
262 } while (0)
263
264 #define CARP_LOG(...) do { \
265 if (V_carp_log > 0) \
266 log(LOG_INFO, "carp: " __VA_ARGS__); \
267 } while (0)
268
269 #define CARP_DEBUG(...) do { \
270 if (V_carp_log > 1) \
271 log(LOG_DEBUG, __VA_ARGS__); \
272 } while (0)
273
274 #define IFNET_FOREACH_IFA(ifp, ifa) \
275 IF_ADDR_LOCK_ASSERT(ifp); \
276 TAILQ_FOREACH((ifa), &(ifp)->if_addrhead, ifa_link) \
277 if ((ifa)->ifa_carp != NULL)
278
279 #define CARP_FOREACH_IFA(sc, ifa) \
280 CARP_LOCK_ASSERT(sc); \
281 for (int _i = 0; \
282 _i < (sc)->sc_naddrs + (sc)->sc_naddrs6 && \
283 ((ifa) = sc->sc_ifas[_i]) != NULL; \
284 ++_i)
285
286 #define IFNET_FOREACH_CARP(ifp, sc) \
287 CIF_LOCK_ASSERT(ifp->if_carp); \
288 TAILQ_FOREACH((sc), &(ifp)->if_carp->cif_vrs, sc_list)
289
290 #define DEMOTE_ADVSKEW(sc) \
291 (((sc)->sc_advskew + V_carp_demotion > CARP_MAXSKEW) ? \
292 CARP_MAXSKEW : ((sc)->sc_advskew + V_carp_demotion))
293
294 static void carp_input_c(struct mbuf *, struct carp_header *, sa_family_t);
295 static struct carp_softc
296 *carp_alloc(struct ifnet *);
297 static void carp_detach_locked(struct ifaddr *);
298 static void carp_destroy(struct carp_softc *);
299 static struct carp_if
300 *carp_alloc_if(struct ifnet *);
301 static void carp_free_if(struct carp_if *);
302 static void carp_set_state(struct carp_softc *, int);
303 static void carp_sc_state(struct carp_softc *);
304 static void carp_setrun(struct carp_softc *, sa_family_t);
305 static void carp_master_down(void *);
306 static void carp_master_down_locked(struct carp_softc *);
307 static void carp_send_ad(void *);
308 static void carp_send_ad_locked(struct carp_softc *);
309 static void carp_addroute(struct carp_softc *);
310 static void carp_ifa_addroute(struct ifaddr *);
311 static void carp_delroute(struct carp_softc *);
312 static void carp_ifa_delroute(struct ifaddr *);
313 static void carp_send_ad_all(void *, int);
314 static void carp_demote_adj(int, char *);
315
316 static LIST_HEAD(, carp_softc) carp_list;
317 static struct mtx carp_mtx;
318 static struct task carp_sendall_task =
319 TASK_INITIALIZER(0, carp_send_ad_all, NULL);
320
321 static void
carp_hmac_prepare(struct carp_softc * sc)322 carp_hmac_prepare(struct carp_softc *sc)
323 {
324 uint8_t version = CARP_VERSION, type = CARP_ADVERTISEMENT;
325 uint8_t vhid = sc->sc_vhid & 0xff;
326 struct ifaddr *ifa;
327 int i, found;
328 #ifdef INET
329 struct in_addr last, cur, in;
330 #endif
331 #ifdef INET6
332 struct in6_addr last6, cur6, in6;
333 #endif
334
335 CARP_LOCK_ASSERT(sc);
336
337 /* Compute ipad from key. */
338 bzero(sc->sc_pad, sizeof(sc->sc_pad));
339 bcopy(sc->sc_key, sc->sc_pad, sizeof(sc->sc_key));
340 for (i = 0; i < sizeof(sc->sc_pad); i++)
341 sc->sc_pad[i] ^= 0x36;
342
343 /* Precompute first part of inner hash. */
344 SHA1Init(&sc->sc_sha1);
345 SHA1Update(&sc->sc_sha1, sc->sc_pad, sizeof(sc->sc_pad));
346 SHA1Update(&sc->sc_sha1, (void *)&version, sizeof(version));
347 SHA1Update(&sc->sc_sha1, (void *)&type, sizeof(type));
348 SHA1Update(&sc->sc_sha1, (void *)&vhid, sizeof(vhid));
349 #ifdef INET
350 cur.s_addr = 0;
351 do {
352 found = 0;
353 last = cur;
354 cur.s_addr = 0xffffffff;
355 CARP_FOREACH_IFA(sc, ifa) {
356 in.s_addr = ifatoia(ifa)->ia_addr.sin_addr.s_addr;
357 if (ifa->ifa_addr->sa_family == AF_INET &&
358 ntohl(in.s_addr) > ntohl(last.s_addr) &&
359 ntohl(in.s_addr) < ntohl(cur.s_addr)) {
360 cur.s_addr = in.s_addr;
361 found++;
362 }
363 }
364 if (found)
365 SHA1Update(&sc->sc_sha1, (void *)&cur, sizeof(cur));
366 } while (found);
367 #endif /* INET */
368 #ifdef INET6
369 memset(&cur6, 0, sizeof(cur6));
370 do {
371 found = 0;
372 last6 = cur6;
373 memset(&cur6, 0xff, sizeof(cur6));
374 CARP_FOREACH_IFA(sc, ifa) {
375 in6 = ifatoia6(ifa)->ia_addr.sin6_addr;
376 if (IN6_IS_SCOPE_EMBED(&in6))
377 in6.s6_addr16[1] = 0;
378 if (ifa->ifa_addr->sa_family == AF_INET6 &&
379 memcmp(&in6, &last6, sizeof(in6)) > 0 &&
380 memcmp(&in6, &cur6, sizeof(in6)) < 0) {
381 cur6 = in6;
382 found++;
383 }
384 }
385 if (found)
386 SHA1Update(&sc->sc_sha1, (void *)&cur6, sizeof(cur6));
387 } while (found);
388 #endif /* INET6 */
389
390 /* convert ipad to opad */
391 for (i = 0; i < sizeof(sc->sc_pad); i++)
392 sc->sc_pad[i] ^= 0x36 ^ 0x5c;
393 }
394
395 static void
carp_hmac_generate(struct carp_softc * sc,uint32_t counter[2],unsigned char md[20])396 carp_hmac_generate(struct carp_softc *sc, uint32_t counter[2],
397 unsigned char md[20])
398 {
399 SHA1_CTX sha1ctx;
400
401 CARP_LOCK_ASSERT(sc);
402
403 /* fetch first half of inner hash */
404 bcopy(&sc->sc_sha1, &sha1ctx, sizeof(sha1ctx));
405
406 SHA1Update(&sha1ctx, (void *)counter, sizeof(sc->sc_counter));
407 SHA1Final(md, &sha1ctx);
408
409 /* outer hash */
410 SHA1Init(&sha1ctx);
411 SHA1Update(&sha1ctx, sc->sc_pad, sizeof(sc->sc_pad));
412 SHA1Update(&sha1ctx, md, 20);
413 SHA1Final(md, &sha1ctx);
414 }
415
416 static int
carp_hmac_verify(struct carp_softc * sc,uint32_t counter[2],unsigned char md[20])417 carp_hmac_verify(struct carp_softc *sc, uint32_t counter[2],
418 unsigned char md[20])
419 {
420 unsigned char md2[20];
421
422 CARP_LOCK_ASSERT(sc);
423
424 carp_hmac_generate(sc, counter, md2);
425
426 return (bcmp(md, md2, sizeof(md2)));
427 }
428
429 /*
430 * process input packet.
431 * we have rearranged checks order compared to the rfc,
432 * but it seems more efficient this way or not possible otherwise.
433 */
434 #ifdef INET
435 void
carp_input(struct mbuf * m,int hlen)436 carp_input(struct mbuf *m, int hlen)
437 {
438 struct ip *ip = mtod(m, struct ip *);
439 struct carp_header *ch;
440 int iplen, len;
441
442 CARPSTATS_INC(carps_ipackets);
443
444 if (!V_carp_allow) {
445 m_freem(m);
446 return;
447 }
448
449 /* verify that the IP TTL is 255. */
450 if (ip->ip_ttl != CARP_DFLTTL) {
451 CARPSTATS_INC(carps_badttl);
452 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
453 ip->ip_ttl,
454 m->m_pkthdr.rcvif->if_xname);
455 m_freem(m);
456 return;
457 }
458
459 iplen = ip->ip_hl << 2;
460
461 if (m->m_pkthdr.len < iplen + sizeof(*ch)) {
462 CARPSTATS_INC(carps_badlen);
463 CARP_DEBUG("%s: received len %zd < sizeof(struct carp_header) "
464 "on %s\n", __func__, m->m_len - sizeof(struct ip),
465 m->m_pkthdr.rcvif->if_xname);
466 m_freem(m);
467 return;
468 }
469
470 if (iplen + sizeof(*ch) < m->m_len) {
471 if ((m = m_pullup(m, iplen + sizeof(*ch))) == NULL) {
472 CARPSTATS_INC(carps_hdrops);
473 CARP_DEBUG("%s: pullup failed\n", __func__);
474 return;
475 }
476 ip = mtod(m, struct ip *);
477 }
478 ch = (struct carp_header *)((char *)ip + iplen);
479
480 /*
481 * verify that the received packet length is
482 * equal to the CARP header
483 */
484 len = iplen + sizeof(*ch);
485 if (len > m->m_pkthdr.len) {
486 CARPSTATS_INC(carps_badlen);
487 CARP_DEBUG("%s: packet too short %d on %s\n", __func__,
488 m->m_pkthdr.len,
489 m->m_pkthdr.rcvif->if_xname);
490 m_freem(m);
491 return;
492 }
493
494 if ((m = m_pullup(m, len)) == NULL) {
495 CARPSTATS_INC(carps_hdrops);
496 return;
497 }
498 ip = mtod(m, struct ip *);
499 ch = (struct carp_header *)((char *)ip + iplen);
500
501 /* verify the CARP checksum */
502 m->m_data += iplen;
503 if (in_cksum(m, len - iplen)) {
504 CARPSTATS_INC(carps_badsum);
505 CARP_DEBUG("%s: checksum failed on %s\n", __func__,
506 m->m_pkthdr.rcvif->if_xname);
507 m_freem(m);
508 return;
509 }
510 m->m_data -= iplen;
511
512 carp_input_c(m, ch, AF_INET);
513 }
514 #endif
515
516 #ifdef INET6
517 int
carp6_input(struct mbuf ** mp,int * offp,int proto)518 carp6_input(struct mbuf **mp, int *offp, int proto)
519 {
520 struct mbuf *m = *mp;
521 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
522 struct carp_header *ch;
523 u_int len;
524
525 CARPSTATS_INC(carps_ipackets6);
526
527 if (!V_carp_allow) {
528 m_freem(m);
529 return (IPPROTO_DONE);
530 }
531
532 /* check if received on a valid carp interface */
533 if (m->m_pkthdr.rcvif->if_carp == NULL) {
534 CARPSTATS_INC(carps_badif);
535 CARP_DEBUG("%s: packet received on non-carp interface: %s\n",
536 __func__, m->m_pkthdr.rcvif->if_xname);
537 m_freem(m);
538 return (IPPROTO_DONE);
539 }
540
541 /* verify that the IP TTL is 255 */
542 if (ip6->ip6_hlim != CARP_DFLTTL) {
543 CARPSTATS_INC(carps_badttl);
544 CARP_DEBUG("%s: received ttl %d != 255 on %s\n", __func__,
545 ip6->ip6_hlim, m->m_pkthdr.rcvif->if_xname);
546 m_freem(m);
547 return (IPPROTO_DONE);
548 }
549
550 /* verify that we have a complete carp packet */
551 len = m->m_len;
552 IP6_EXTHDR_GET(ch, struct carp_header *, m, *offp, sizeof(*ch));
553 if (ch == NULL) {
554 CARPSTATS_INC(carps_badlen);
555 CARP_DEBUG("%s: packet size %u too small\n", __func__, len);
556 return (IPPROTO_DONE);
557 }
558
559
560 /* verify the CARP checksum */
561 m->m_data += *offp;
562 if (in_cksum(m, sizeof(*ch))) {
563 CARPSTATS_INC(carps_badsum);
564 CARP_DEBUG("%s: checksum failed, on %s\n", __func__,
565 m->m_pkthdr.rcvif->if_xname);
566 m_freem(m);
567 return (IPPROTO_DONE);
568 }
569 m->m_data -= *offp;
570
571 carp_input_c(m, ch, AF_INET6);
572 return (IPPROTO_DONE);
573 }
574 #endif /* INET6 */
575
576 static void
carp_input_c(struct mbuf * m,struct carp_header * ch,sa_family_t af)577 carp_input_c(struct mbuf *m, struct carp_header *ch, sa_family_t af)
578 {
579 struct ifnet *ifp = m->m_pkthdr.rcvif;
580 struct ifaddr *ifa;
581 struct carp_softc *sc;
582 uint64_t tmp_counter;
583 struct timeval sc_tv, ch_tv;
584
585 /* verify that the VHID is valid on the receiving interface */
586 IF_ADDR_RLOCK(ifp);
587 IFNET_FOREACH_IFA(ifp, ifa)
588 if (ifa->ifa_addr->sa_family == af &&
589 ifa->ifa_carp->sc_vhid == ch->carp_vhid) {
590 ifa_ref(ifa);
591 break;
592 }
593 IF_ADDR_RUNLOCK(ifp);
594
595 if (ifa == NULL) {
596 CARPSTATS_INC(carps_badvhid);
597 m_freem(m);
598 return;
599 }
600
601 /* verify the CARP version. */
602 if (ch->carp_version != CARP_VERSION) {
603 CARPSTATS_INC(carps_badver);
604 CARP_DEBUG("%s: invalid version %d\n", ifp->if_xname,
605 ch->carp_version);
606 ifa_free(ifa);
607 m_freem(m);
608 return;
609 }
610
611 sc = ifa->ifa_carp;
612 CARP_LOCK(sc);
613 ifa_free(ifa);
614
615 if (carp_hmac_verify(sc, ch->carp_counter, ch->carp_md)) {
616 CARPSTATS_INC(carps_badauth);
617 CARP_DEBUG("%s: incorrect hash for VHID %u@%s\n", __func__,
618 sc->sc_vhid, ifp->if_xname);
619 goto out;
620 }
621
622 tmp_counter = ntohl(ch->carp_counter[0]);
623 tmp_counter = tmp_counter<<32;
624 tmp_counter += ntohl(ch->carp_counter[1]);
625
626 /* XXX Replay protection goes here */
627
628 sc->sc_init_counter = 0;
629 sc->sc_counter = tmp_counter;
630
631 sc_tv.tv_sec = sc->sc_advbase;
632 sc_tv.tv_usec = DEMOTE_ADVSKEW(sc) * 1000000 / 256;
633 ch_tv.tv_sec = ch->carp_advbase;
634 ch_tv.tv_usec = ch->carp_advskew * 1000000 / 256;
635
636 switch (sc->sc_state) {
637 case INIT:
638 break;
639 case MASTER:
640 /*
641 * If we receive an advertisement from a master who's going to
642 * be more frequent than us, go into BACKUP state.
643 */
644 if (timevalcmp(&sc_tv, &ch_tv, >) ||
645 timevalcmp(&sc_tv, &ch_tv, ==)) {
646 callout_stop(&sc->sc_ad_tmo);
647 CARP_LOG("VHID %u@%s: MASTER -> BACKUP "
648 "(more frequent advertisement received)\n",
649 sc->sc_vhid,
650 sc->sc_carpdev->if_xname);
651 carp_set_state(sc, BACKUP);
652 carp_setrun(sc, 0);
653 carp_delroute(sc);
654 }
655 break;
656 case BACKUP:
657 /*
658 * If we're pre-empting masters who advertise slower than us,
659 * and this one claims to be slower, treat him as down.
660 */
661 if (V_carp_preempt && timevalcmp(&sc_tv, &ch_tv, <)) {
662 CARP_LOG("VHID %u@%s: BACKUP -> MASTER "
663 "(preempting a slower master)\n",
664 sc->sc_vhid,
665 sc->sc_carpdev->if_xname);
666 carp_master_down_locked(sc);
667 break;
668 }
669
670 /*
671 * If the master is going to advertise at such a low frequency
672 * that he's guaranteed to time out, we'd might as well just
673 * treat him as timed out now.
674 */
675 sc_tv.tv_sec = sc->sc_advbase * 3;
676 if (timevalcmp(&sc_tv, &ch_tv, <)) {
677 CARP_LOG("VHID %u@%s: BACKUP -> MASTER "
678 "(master timed out)\n",
679 sc->sc_vhid,
680 sc->sc_carpdev->if_xname);
681 carp_master_down_locked(sc);
682 break;
683 }
684
685 /*
686 * Otherwise, we reset the counter and wait for the next
687 * advertisement.
688 */
689 carp_setrun(sc, af);
690 break;
691 }
692
693 out:
694 CARP_UNLOCK(sc);
695 m_freem(m);
696 }
697
698 static int
carp_prepare_ad(struct mbuf * m,struct carp_softc * sc,struct carp_header * ch)699 carp_prepare_ad(struct mbuf *m, struct carp_softc *sc, struct carp_header *ch)
700 {
701 struct m_tag *mtag;
702
703 if (sc->sc_init_counter) {
704 /* this could also be seconds since unix epoch */
705 sc->sc_counter = arc4random();
706 sc->sc_counter = sc->sc_counter << 32;
707 sc->sc_counter += arc4random();
708 } else
709 sc->sc_counter++;
710
711 ch->carp_counter[0] = htonl((sc->sc_counter>>32)&0xffffffff);
712 ch->carp_counter[1] = htonl(sc->sc_counter&0xffffffff);
713
714 carp_hmac_generate(sc, ch->carp_counter, ch->carp_md);
715
716 /* Tag packet for carp_output */
717 if ((mtag = m_tag_get(PACKET_TAG_CARP, sizeof(struct carp_softc *),
718 M_NOWAIT)) == NULL) {
719 m_freem(m);
720 CARPSTATS_INC(carps_onomem);
721 return (ENOMEM);
722 }
723 bcopy(&sc, mtag + 1, sizeof(sc));
724 m_tag_prepend(m, mtag);
725
726 return (0);
727 }
728
729 /*
730 * To avoid LORs and possible recursions this function shouldn't
731 * be called directly, but scheduled via taskqueue.
732 */
733 static void
carp_send_ad_all(void * ctx __unused,int pending __unused)734 carp_send_ad_all(void *ctx __unused, int pending __unused)
735 {
736 struct carp_softc *sc;
737
738 mtx_lock(&carp_mtx);
739 LIST_FOREACH(sc, &carp_list, sc_next)
740 if (sc->sc_state == MASTER) {
741 CARP_LOCK(sc);
742 CURVNET_SET(sc->sc_carpdev->if_vnet);
743 carp_send_ad_locked(sc);
744 CURVNET_RESTORE();
745 CARP_UNLOCK(sc);
746 }
747 mtx_unlock(&carp_mtx);
748 }
749
750 /* Send a periodic advertisement, executed in callout context. */
751 static void
carp_send_ad(void * v)752 carp_send_ad(void *v)
753 {
754 struct carp_softc *sc = v;
755
756 CARP_LOCK_ASSERT(sc);
757 CURVNET_SET(sc->sc_carpdev->if_vnet);
758 carp_send_ad_locked(sc);
759 CURVNET_RESTORE();
760 CARP_UNLOCK(sc);
761 }
762
763 static void
carp_send_ad_error(struct carp_softc * sc,int error)764 carp_send_ad_error(struct carp_softc *sc, int error)
765 {
766
767 if (error) {
768 if (sc->sc_sendad_errors < INT_MAX)
769 sc->sc_sendad_errors++;
770 if (sc->sc_sendad_errors == CARP_SENDAD_MAX_ERRORS) {
771 static const char fmt[] = "send error %d on %s";
772 char msg[sizeof(fmt) + IFNAMSIZ];
773
774 sprintf(msg, fmt, error, sc->sc_carpdev->if_xname);
775 carp_demote_adj(V_carp_senderr_adj, msg);
776 }
777 sc->sc_sendad_success = 0;
778 } else {
779 if (sc->sc_sendad_errors >= CARP_SENDAD_MAX_ERRORS &&
780 ++sc->sc_sendad_success >= CARP_SENDAD_MIN_SUCCESS) {
781 static const char fmt[] = "send ok on %s";
782 char msg[sizeof(fmt) + IFNAMSIZ];
783
784 sprintf(msg, fmt, sc->sc_carpdev->if_xname);
785 carp_demote_adj(-V_carp_senderr_adj, msg);
786 sc->sc_sendad_errors = 0;
787 } else
788 sc->sc_sendad_errors = 0;
789 }
790 }
791
792 static void
carp_send_ad_locked(struct carp_softc * sc)793 carp_send_ad_locked(struct carp_softc *sc)
794 {
795 struct carp_header ch;
796 struct timeval tv;
797 struct sockaddr sa;
798 struct ifaddr *ifa;
799 struct carp_header *ch_ptr;
800 struct mbuf *m;
801 int len, advskew;
802
803 CARP_LOCK_ASSERT(sc);
804
805 advskew = DEMOTE_ADVSKEW(sc);
806 tv.tv_sec = sc->sc_advbase;
807 tv.tv_usec = advskew * 1000000 / 256;
808
809 ch.carp_version = CARP_VERSION;
810 ch.carp_type = CARP_ADVERTISEMENT;
811 ch.carp_vhid = sc->sc_vhid;
812 ch.carp_advbase = sc->sc_advbase;
813 ch.carp_advskew = advskew;
814 ch.carp_authlen = 7; /* XXX DEFINE */
815 ch.carp_pad1 = 0; /* must be zero */
816 ch.carp_cksum = 0;
817
818 /* XXXGL: OpenBSD picks first ifaddr with needed family. */
819
820 #ifdef INET
821 if (sc->sc_naddrs) {
822 struct ip *ip;
823
824 m = m_gethdr(M_NOWAIT, MT_DATA);
825 if (m == NULL) {
826 CARPSTATS_INC(carps_onomem);
827 goto resched;
828 }
829 len = sizeof(*ip) + sizeof(ch);
830 m->m_pkthdr.len = len;
831 m->m_pkthdr.rcvif = NULL;
832 m->m_len = len;
833 MH_ALIGN(m, m->m_len);
834 m->m_flags |= M_MCAST;
835 ip = mtod(m, struct ip *);
836 ip->ip_v = IPVERSION;
837 ip->ip_hl = sizeof(*ip) >> 2;
838 ip->ip_tos = IPTOS_LOWDELAY;
839 ip->ip_len = htons(len);
840 ip->ip_id = ip_newid();
841 ip->ip_off = htons(IP_DF);
842 ip->ip_ttl = CARP_DFLTTL;
843 ip->ip_p = IPPROTO_CARP;
844 ip->ip_sum = 0;
845
846 bzero(&sa, sizeof(sa));
847 sa.sa_family = AF_INET;
848 ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
849 if (ifa != NULL) {
850 ip->ip_src.s_addr =
851 ifatoia(ifa)->ia_addr.sin_addr.s_addr;
852 ifa_free(ifa);
853 } else
854 ip->ip_src.s_addr = 0;
855 ip->ip_dst.s_addr = htonl(INADDR_CARP_GROUP);
856
857 ch_ptr = (struct carp_header *)(&ip[1]);
858 bcopy(&ch, ch_ptr, sizeof(ch));
859 if (carp_prepare_ad(m, sc, ch_ptr))
860 goto resched;
861
862 m->m_data += sizeof(*ip);
863 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip));
864 m->m_data -= sizeof(*ip);
865
866 CARPSTATS_INC(carps_opackets);
867
868 carp_send_ad_error(sc, ip_output(m, NULL, NULL, IP_RAWOUTPUT,
869 &sc->sc_carpdev->if_carp->cif_imo, NULL));
870 }
871 #endif /* INET */
872 #ifdef INET6
873 if (sc->sc_naddrs6) {
874 struct ip6_hdr *ip6;
875
876 m = m_gethdr(M_NOWAIT, MT_DATA);
877 if (m == NULL) {
878 CARPSTATS_INC(carps_onomem);
879 goto resched;
880 }
881 len = sizeof(*ip6) + sizeof(ch);
882 m->m_pkthdr.len = len;
883 m->m_pkthdr.rcvif = NULL;
884 m->m_len = len;
885 MH_ALIGN(m, m->m_len);
886 m->m_flags |= M_MCAST;
887 ip6 = mtod(m, struct ip6_hdr *);
888 bzero(ip6, sizeof(*ip6));
889 ip6->ip6_vfc |= IPV6_VERSION;
890 ip6->ip6_hlim = CARP_DFLTTL;
891 ip6->ip6_nxt = IPPROTO_CARP;
892 bzero(&sa, sizeof(sa));
893
894 /* set the source address */
895 sa.sa_family = AF_INET6;
896 ifa = ifaof_ifpforaddr(&sa, sc->sc_carpdev);
897 if (ifa != NULL) {
898 bcopy(IFA_IN6(ifa), &ip6->ip6_src,
899 sizeof(struct in6_addr));
900 ifa_free(ifa);
901 } else
902 /* This should never happen with IPv6. */
903 bzero(&ip6->ip6_src, sizeof(struct in6_addr));
904
905 /* Set the multicast destination. */
906 ip6->ip6_dst.s6_addr16[0] = htons(0xff02);
907 ip6->ip6_dst.s6_addr8[15] = 0x12;
908 if (in6_setscope(&ip6->ip6_dst, sc->sc_carpdev, NULL) != 0) {
909 m_freem(m);
910 CARP_DEBUG("%s: in6_setscope failed\n", __func__);
911 goto resched;
912 }
913
914 ch_ptr = (struct carp_header *)(&ip6[1]);
915 bcopy(&ch, ch_ptr, sizeof(ch));
916 if (carp_prepare_ad(m, sc, ch_ptr))
917 goto resched;
918
919 m->m_data += sizeof(*ip6);
920 ch_ptr->carp_cksum = in_cksum(m, len - sizeof(*ip6));
921 m->m_data -= sizeof(*ip6);
922
923 CARPSTATS_INC(carps_opackets6);
924
925 carp_send_ad_error(sc, ip6_output(m, NULL, NULL, 0,
926 &sc->sc_carpdev->if_carp->cif_im6o, NULL, NULL));
927 }
928 #endif /* INET6 */
929
930 resched:
931 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv), carp_send_ad, sc);
932 }
933
934 static void
carp_addroute(struct carp_softc * sc)935 carp_addroute(struct carp_softc *sc)
936 {
937 struct ifaddr *ifa;
938
939 CARP_FOREACH_IFA(sc, ifa)
940 carp_ifa_addroute(ifa);
941 }
942
943 static void
carp_ifa_addroute(struct ifaddr * ifa)944 carp_ifa_addroute(struct ifaddr *ifa)
945 {
946
947 switch (ifa->ifa_addr->sa_family) {
948 #ifdef INET
949 case AF_INET:
950 in_addprefix(ifatoia(ifa), RTF_UP);
951 ifa_add_loopback_route(ifa,
952 (struct sockaddr *)&ifatoia(ifa)->ia_addr);
953 break;
954 #endif
955 #ifdef INET6
956 case AF_INET6:
957 ifa_add_loopback_route(ifa,
958 (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
959 in6_ifaddloop(ifa);
960 break;
961 #endif
962 }
963 }
964
965 static void
carp_delroute(struct carp_softc * sc)966 carp_delroute(struct carp_softc *sc)
967 {
968 struct ifaddr *ifa;
969
970 CARP_FOREACH_IFA(sc, ifa)
971 carp_ifa_delroute(ifa);
972 }
973
974 static void
carp_ifa_delroute(struct ifaddr * ifa)975 carp_ifa_delroute(struct ifaddr *ifa)
976 {
977
978 switch (ifa->ifa_addr->sa_family) {
979 #ifdef INET
980 case AF_INET:
981 ifa_del_loopback_route(ifa,
982 (struct sockaddr *)&ifatoia(ifa)->ia_addr);
983 in_scrubprefix(ifatoia(ifa), LLE_STATIC);
984 break;
985 #endif
986 #ifdef INET6
987 case AF_INET6:
988 ifa_del_loopback_route(ifa,
989 (struct sockaddr *)&ifatoia6(ifa)->ia_addr);
990 in6_ifremloop(ifa);
991 break;
992 #endif
993 }
994 }
995
996 int
carp_master(struct ifaddr * ifa)997 carp_master(struct ifaddr *ifa)
998 {
999 struct carp_softc *sc = ifa->ifa_carp;
1000
1001 return (sc->sc_state == MASTER);
1002 }
1003
1004 #ifdef INET
1005 /*
1006 * Broadcast a gratuitous ARP request containing
1007 * the virtual router MAC address for each IP address
1008 * associated with the virtual router.
1009 */
1010 static void
carp_send_arp(struct carp_softc * sc)1011 carp_send_arp(struct carp_softc *sc)
1012 {
1013 struct ifaddr *ifa;
1014
1015 CARP_FOREACH_IFA(sc, ifa)
1016 if (ifa->ifa_addr->sa_family == AF_INET)
1017 arp_ifinit2(sc->sc_carpdev, ifa, LLADDR(&sc->sc_addr));
1018 }
1019
1020 int
carp_iamatch(struct ifaddr * ifa,uint8_t ** enaddr)1021 carp_iamatch(struct ifaddr *ifa, uint8_t **enaddr)
1022 {
1023 struct carp_softc *sc = ifa->ifa_carp;
1024
1025 if (sc->sc_state == MASTER) {
1026 *enaddr = LLADDR(&sc->sc_addr);
1027 return (1);
1028 }
1029
1030 return (0);
1031 }
1032 #endif
1033
1034 #ifdef INET6
1035 static void
carp_send_na(struct carp_softc * sc)1036 carp_send_na(struct carp_softc *sc)
1037 {
1038 static struct in6_addr mcast = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
1039 struct ifaddr *ifa;
1040 struct in6_addr *in6;
1041
1042 CARP_FOREACH_IFA(sc, ifa) {
1043 if (ifa->ifa_addr->sa_family != AF_INET6)
1044 continue;
1045
1046 in6 = IFA_IN6(ifa);
1047 nd6_na_output(sc->sc_carpdev, &mcast, in6,
1048 ND_NA_FLAG_OVERRIDE, 1, NULL);
1049 DELAY(1000); /* XXX */
1050 }
1051 }
1052
1053 /*
1054 * Returns ifa in case it's a carp address and it is MASTER, or if the address
1055 * matches and is not a carp address. Returns NULL otherwise.
1056 */
1057 struct ifaddr *
carp_iamatch6(struct ifnet * ifp,struct in6_addr * taddr)1058 carp_iamatch6(struct ifnet *ifp, struct in6_addr *taddr)
1059 {
1060 struct ifaddr *ifa;
1061
1062 ifa = NULL;
1063 IF_ADDR_RLOCK(ifp);
1064 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
1065 if (ifa->ifa_addr->sa_family != AF_INET6)
1066 continue;
1067 if (!IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa)))
1068 continue;
1069 if (ifa->ifa_carp && ifa->ifa_carp->sc_state != MASTER)
1070 ifa = NULL;
1071 else
1072 ifa_ref(ifa);
1073 break;
1074 }
1075 IF_ADDR_RUNLOCK(ifp);
1076
1077 return (ifa);
1078 }
1079
1080 caddr_t
carp_macmatch6(struct ifnet * ifp,struct mbuf * m,const struct in6_addr * taddr)1081 carp_macmatch6(struct ifnet *ifp, struct mbuf *m, const struct in6_addr *taddr)
1082 {
1083 struct ifaddr *ifa;
1084
1085 IF_ADDR_RLOCK(ifp);
1086 IFNET_FOREACH_IFA(ifp, ifa)
1087 if (ifa->ifa_addr->sa_family == AF_INET6 &&
1088 IN6_ARE_ADDR_EQUAL(taddr, IFA_IN6(ifa))) {
1089 struct carp_softc *sc = ifa->ifa_carp;
1090 struct m_tag *mtag;
1091
1092 IF_ADDR_RUNLOCK(ifp);
1093
1094 mtag = m_tag_get(PACKET_TAG_CARP,
1095 sizeof(struct carp_softc *), M_NOWAIT);
1096 if (mtag == NULL)
1097 /* Better a bit than nothing. */
1098 return (LLADDR(&sc->sc_addr));
1099
1100 bcopy(&sc, mtag + 1, sizeof(sc));
1101 m_tag_prepend(m, mtag);
1102
1103 return (LLADDR(&sc->sc_addr));
1104 }
1105 IF_ADDR_RUNLOCK(ifp);
1106
1107 return (NULL);
1108 }
1109 #endif /* INET6 */
1110
1111 int
carp_forus(struct ifnet * ifp,u_char * dhost)1112 carp_forus(struct ifnet *ifp, u_char *dhost)
1113 {
1114 struct carp_softc *sc;
1115 uint8_t *ena = dhost;
1116
1117 if (ena[0] || ena[1] || ena[2] != 0x5e || ena[3] || ena[4] != 1)
1118 return (0);
1119
1120 CIF_LOCK(ifp->if_carp);
1121 IFNET_FOREACH_CARP(ifp, sc) {
1122 CARP_LOCK(sc);
1123 if (sc->sc_state == MASTER && !bcmp(dhost, LLADDR(&sc->sc_addr),
1124 ETHER_ADDR_LEN)) {
1125 CARP_UNLOCK(sc);
1126 CIF_UNLOCK(ifp->if_carp);
1127 return (1);
1128 }
1129 CARP_UNLOCK(sc);
1130 }
1131 CIF_UNLOCK(ifp->if_carp);
1132
1133 return (0);
1134 }
1135
1136 /* Master down timeout event, executed in callout context. */
1137 static void
carp_master_down(void * v)1138 carp_master_down(void *v)
1139 {
1140 struct carp_softc *sc = v;
1141
1142 CARP_LOCK_ASSERT(sc);
1143
1144 CURVNET_SET(sc->sc_carpdev->if_vnet);
1145 if (sc->sc_state == BACKUP) {
1146 CARP_LOG("VHID %u@%s: BACKUP -> MASTER (master down)\n",
1147 sc->sc_vhid,
1148 sc->sc_carpdev->if_xname);
1149 carp_master_down_locked(sc);
1150 }
1151 CURVNET_RESTORE();
1152
1153 CARP_UNLOCK(sc);
1154 }
1155
1156 static void
carp_master_down_locked(struct carp_softc * sc)1157 carp_master_down_locked(struct carp_softc *sc)
1158 {
1159
1160 CARP_LOCK_ASSERT(sc);
1161
1162 switch (sc->sc_state) {
1163 case BACKUP:
1164 carp_set_state(sc, MASTER);
1165 carp_send_ad_locked(sc);
1166 #ifdef INET
1167 carp_send_arp(sc);
1168 #endif
1169 #ifdef INET6
1170 carp_send_na(sc);
1171 #endif
1172 carp_setrun(sc, 0);
1173 carp_addroute(sc);
1174 break;
1175 case INIT:
1176 case MASTER:
1177 #ifdef INVARIANTS
1178 panic("carp: VHID %u@%s: master_down event in %s state\n",
1179 sc->sc_vhid,
1180 sc->sc_carpdev->if_xname,
1181 sc->sc_state ? "MASTER" : "INIT");
1182 #endif
1183 break;
1184 }
1185 }
1186
1187 /*
1188 * When in backup state, af indicates whether to reset the master down timer
1189 * for v4 or v6. If it's set to zero, reset the ones which are already pending.
1190 */
1191 static void
carp_setrun(struct carp_softc * sc,sa_family_t af)1192 carp_setrun(struct carp_softc *sc, sa_family_t af)
1193 {
1194 struct timeval tv;
1195
1196 CARP_LOCK_ASSERT(sc);
1197
1198 if ((sc->sc_carpdev->if_flags & IFF_UP) == 0 ||
1199 sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
1200 (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0))
1201 return;
1202
1203 switch (sc->sc_state) {
1204 case INIT:
1205 CARP_LOG("VHID %u@%s: INIT -> BACKUP\n",
1206 sc->sc_vhid,
1207 sc->sc_carpdev->if_xname);
1208 carp_set_state(sc, BACKUP);
1209 carp_setrun(sc, 0);
1210 break;
1211 case BACKUP:
1212 callout_stop(&sc->sc_ad_tmo);
1213 tv.tv_sec = 3 * sc->sc_advbase;
1214 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1215 switch (af) {
1216 #ifdef INET
1217 case AF_INET:
1218 callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1219 carp_master_down, sc);
1220 break;
1221 #endif
1222 #ifdef INET6
1223 case AF_INET6:
1224 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1225 carp_master_down, sc);
1226 break;
1227 #endif
1228 default:
1229 #ifdef INET
1230 if (sc->sc_naddrs)
1231 callout_reset(&sc->sc_md_tmo, tvtohz(&tv),
1232 carp_master_down, sc);
1233 #endif
1234 #ifdef INET6
1235 if (sc->sc_naddrs6)
1236 callout_reset(&sc->sc_md6_tmo, tvtohz(&tv),
1237 carp_master_down, sc);
1238 #endif
1239 break;
1240 }
1241 break;
1242 case MASTER:
1243 tv.tv_sec = sc->sc_advbase;
1244 tv.tv_usec = sc->sc_advskew * 1000000 / 256;
1245 callout_reset(&sc->sc_ad_tmo, tvtohz(&tv),
1246 carp_send_ad, sc);
1247 break;
1248 }
1249 }
1250
1251 /*
1252 * Setup multicast structures.
1253 */
1254 static int
carp_multicast_setup(struct carp_if * cif,sa_family_t sa)1255 carp_multicast_setup(struct carp_if *cif, sa_family_t sa)
1256 {
1257 struct ifnet *ifp = cif->cif_ifp;
1258 int error = 0;
1259
1260 CIF_LOCK_ASSERT(cif);
1261
1262 switch (sa) {
1263 #ifdef INET
1264 case AF_INET:
1265 {
1266 struct ip_moptions *imo = &cif->cif_imo;
1267 struct in_addr addr;
1268
1269 if (imo->imo_membership)
1270 return (0);
1271
1272 imo->imo_membership = (struct in_multi **)malloc(
1273 (sizeof(struct in_multi *) * IP_MIN_MEMBERSHIPS), M_CARP,
1274 M_NOWAIT);
1275 if (imo->imo_membership == NULL)
1276 return (ENOMEM);
1277 imo->imo_mfilters = NULL;
1278 imo->imo_max_memberships = IP_MIN_MEMBERSHIPS;
1279 imo->imo_multicast_vif = -1;
1280
1281 addr.s_addr = htonl(INADDR_CARP_GROUP);
1282 if ((error = in_joingroup(ifp, &addr, NULL,
1283 &imo->imo_membership[0])) != 0) {
1284 free(imo->imo_membership, M_CARP);
1285 break;
1286 }
1287 imo->imo_num_memberships++;
1288 imo->imo_multicast_ifp = ifp;
1289 imo->imo_multicast_ttl = CARP_DFLTTL;
1290 imo->imo_multicast_loop = 0;
1291 break;
1292 }
1293 #endif
1294 #ifdef INET6
1295 case AF_INET6:
1296 {
1297 struct ip6_moptions *im6o = &cif->cif_im6o;
1298 struct in6_addr in6;
1299 struct in6_multi *in6m;
1300
1301 if (im6o->im6o_membership)
1302 return (0);
1303
1304 im6o->im6o_membership = (struct in6_multi **)malloc(
1305 (sizeof(struct in6_multi *) * IPV6_MIN_MEMBERSHIPS), M_CARP,
1306 M_ZERO | M_NOWAIT);
1307 if (im6o->im6o_membership == NULL)
1308 return (ENOMEM);
1309 im6o->im6o_mfilters = NULL;
1310 im6o->im6o_max_memberships = IPV6_MIN_MEMBERSHIPS;
1311 im6o->im6o_multicast_hlim = CARP_DFLTTL;
1312 im6o->im6o_multicast_ifp = ifp;
1313
1314 /* Join IPv6 CARP multicast group. */
1315 bzero(&in6, sizeof(in6));
1316 in6.s6_addr16[0] = htons(0xff02);
1317 in6.s6_addr8[15] = 0x12;
1318 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
1319 free(im6o->im6o_membership, M_CARP);
1320 break;
1321 }
1322 in6m = NULL;
1323 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) {
1324 free(im6o->im6o_membership, M_CARP);
1325 break;
1326 }
1327 im6o->im6o_membership[0] = in6m;
1328 im6o->im6o_num_memberships++;
1329
1330 /* Join solicited multicast address. */
1331 bzero(&in6, sizeof(in6));
1332 in6.s6_addr16[0] = htons(0xff02);
1333 in6.s6_addr32[1] = 0;
1334 in6.s6_addr32[2] = htonl(1);
1335 in6.s6_addr32[3] = 0;
1336 in6.s6_addr8[12] = 0xff;
1337 if ((error = in6_setscope(&in6, ifp, NULL)) != 0) {
1338 in6_mc_leave(im6o->im6o_membership[0], NULL);
1339 free(im6o->im6o_membership, M_CARP);
1340 break;
1341 }
1342 in6m = NULL;
1343 if ((error = in6_mc_join(ifp, &in6, NULL, &in6m, 0)) != 0) {
1344 in6_mc_leave(im6o->im6o_membership[0], NULL);
1345 free(im6o->im6o_membership, M_CARP);
1346 break;
1347 }
1348 im6o->im6o_membership[1] = in6m;
1349 im6o->im6o_num_memberships++;
1350 break;
1351 }
1352 #endif
1353 }
1354
1355 return (error);
1356 }
1357
1358 /*
1359 * Free multicast structures.
1360 */
1361 static void
carp_multicast_cleanup(struct carp_if * cif,sa_family_t sa)1362 carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa)
1363 {
1364
1365 CIF_LOCK_ASSERT(cif);
1366 switch (sa) {
1367 #ifdef INET
1368 case AF_INET:
1369 if (cif->cif_naddrs == 0) {
1370 struct ip_moptions *imo = &cif->cif_imo;
1371
1372 in_leavegroup(imo->imo_membership[0], NULL);
1373 KASSERT(imo->imo_mfilters == NULL,
1374 ("%s: imo_mfilters != NULL", __func__));
1375 free(imo->imo_membership, M_CARP);
1376 imo->imo_membership = NULL;
1377
1378 }
1379 break;
1380 #endif
1381 #ifdef INET6
1382 case AF_INET6:
1383 if (cif->cif_naddrs6 == 0) {
1384 struct ip6_moptions *im6o = &cif->cif_im6o;
1385
1386 in6_mc_leave(im6o->im6o_membership[0], NULL);
1387 in6_mc_leave(im6o->im6o_membership[1], NULL);
1388 KASSERT(im6o->im6o_mfilters == NULL,
1389 ("%s: im6o_mfilters != NULL", __func__));
1390 free(im6o->im6o_membership, M_CARP);
1391 im6o->im6o_membership = NULL;
1392 }
1393 break;
1394 #endif
1395 }
1396 }
1397
1398 int
carp_output(struct ifnet * ifp,struct mbuf * m,const struct sockaddr * sa)1399 carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa)
1400 {
1401 struct m_tag *mtag;
1402 struct carp_softc *sc;
1403
1404 if (!sa)
1405 return (0);
1406
1407 switch (sa->sa_family) {
1408 #ifdef INET
1409 case AF_INET:
1410 break;
1411 #endif
1412 #ifdef INET6
1413 case AF_INET6:
1414 break;
1415 #endif
1416 default:
1417 return (0);
1418 }
1419
1420 mtag = m_tag_find(m, PACKET_TAG_CARP, NULL);
1421 if (mtag == NULL)
1422 return (0);
1423
1424 bcopy(mtag + 1, &sc, sizeof(sc));
1425
1426 /* Set the source MAC address to the Virtual Router MAC Address. */
1427 switch (ifp->if_type) {
1428 case IFT_ETHER:
1429 case IFT_BRIDGE:
1430 case IFT_L2VLAN: {
1431 struct ether_header *eh;
1432
1433 eh = mtod(m, struct ether_header *);
1434 eh->ether_shost[0] = 0;
1435 eh->ether_shost[1] = 0;
1436 eh->ether_shost[2] = 0x5e;
1437 eh->ether_shost[3] = 0;
1438 eh->ether_shost[4] = 1;
1439 eh->ether_shost[5] = sc->sc_vhid;
1440 }
1441 break;
1442 case IFT_FDDI: {
1443 struct fddi_header *fh;
1444
1445 fh = mtod(m, struct fddi_header *);
1446 fh->fddi_shost[0] = 0;
1447 fh->fddi_shost[1] = 0;
1448 fh->fddi_shost[2] = 0x5e;
1449 fh->fddi_shost[3] = 0;
1450 fh->fddi_shost[4] = 1;
1451 fh->fddi_shost[5] = sc->sc_vhid;
1452 }
1453 break;
1454 case IFT_ISO88025: {
1455 struct iso88025_header *th;
1456 th = mtod(m, struct iso88025_header *);
1457 th->iso88025_shost[0] = 3;
1458 th->iso88025_shost[1] = 0;
1459 th->iso88025_shost[2] = 0x40 >> (sc->sc_vhid - 1);
1460 th->iso88025_shost[3] = 0x40000 >> (sc->sc_vhid - 1);
1461 th->iso88025_shost[4] = 0;
1462 th->iso88025_shost[5] = 0;
1463 }
1464 break;
1465 default:
1466 printf("%s: carp is not supported for the %d interface type\n",
1467 ifp->if_xname, ifp->if_type);
1468 return (EOPNOTSUPP);
1469 }
1470
1471 return (0);
1472 }
1473
1474 static struct carp_softc*
carp_alloc(struct ifnet * ifp)1475 carp_alloc(struct ifnet *ifp)
1476 {
1477 struct carp_softc *sc;
1478 struct carp_if *cif;
1479
1480 if ((cif = ifp->if_carp) == NULL) {
1481 cif = carp_alloc_if(ifp);
1482 if (cif == NULL)
1483 return (NULL);
1484 }
1485
1486 sc = malloc(sizeof(*sc), M_CARP, M_WAITOK|M_ZERO);
1487
1488 sc->sc_advbase = CARP_DFLTINTV;
1489 sc->sc_vhid = -1; /* required setting */
1490 sc->sc_init_counter = 1;
1491 sc->sc_state = INIT;
1492
1493 sc->sc_ifasiz = sizeof(struct ifaddr *);
1494 sc->sc_ifas = malloc(sc->sc_ifasiz, M_CARP, M_WAITOK|M_ZERO);
1495 sc->sc_carpdev = ifp;
1496
1497 CARP_LOCK_INIT(sc);
1498 #ifdef INET
1499 callout_init_mtx(&sc->sc_md_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1500 #endif
1501 #ifdef INET6
1502 callout_init_mtx(&sc->sc_md6_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1503 #endif
1504 callout_init_mtx(&sc->sc_ad_tmo, &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
1505
1506 CIF_LOCK(cif);
1507 TAILQ_INSERT_TAIL(&cif->cif_vrs, sc, sc_list);
1508 CIF_UNLOCK(cif);
1509
1510 mtx_lock(&carp_mtx);
1511 LIST_INSERT_HEAD(&carp_list, sc, sc_next);
1512 mtx_unlock(&carp_mtx);
1513
1514 return (sc);
1515 }
1516
1517 static int
carp_grow_ifas(struct carp_softc * sc)1518 carp_grow_ifas(struct carp_softc *sc)
1519 {
1520 struct ifaddr **new;
1521
1522 CARP_LOCK_ASSERT(sc);
1523
1524 new = malloc(sc->sc_ifasiz * 2, M_CARP, M_NOWAIT|M_ZERO);
1525 if (new == NULL)
1526 return (ENOMEM);
1527 bcopy(sc->sc_ifas, new, sc->sc_ifasiz);
1528 free(sc->sc_ifas, M_CARP);
1529 sc->sc_ifas = new;
1530 sc->sc_ifasiz *= 2;
1531
1532 return (0);
1533 }
1534
1535 static void
carp_destroy(struct carp_softc * sc)1536 carp_destroy(struct carp_softc *sc)
1537 {
1538 struct ifnet *ifp = sc->sc_carpdev;
1539 struct carp_if *cif = ifp->if_carp;
1540
1541 CIF_LOCK_ASSERT(cif);
1542
1543 TAILQ_REMOVE(&cif->cif_vrs, sc, sc_list);
1544
1545 mtx_lock(&carp_mtx);
1546 LIST_REMOVE(sc, sc_next);
1547 mtx_unlock(&carp_mtx);
1548
1549 CARP_LOCK(sc);
1550 if (sc->sc_suppress)
1551 carp_demote_adj(-V_carp_ifdown_adj, "vhid removed");
1552 callout_drain(&sc->sc_ad_tmo);
1553 #ifdef INET
1554 callout_drain(&sc->sc_md_tmo);
1555 #endif
1556 #ifdef INET6
1557 callout_drain(&sc->sc_md6_tmo);
1558 #endif
1559 CARP_LOCK_DESTROY(sc);
1560
1561 free(sc->sc_ifas, M_CARP);
1562 free(sc, M_CARP);
1563 }
1564
1565 static struct carp_if*
carp_alloc_if(struct ifnet * ifp)1566 carp_alloc_if(struct ifnet *ifp)
1567 {
1568 struct carp_if *cif;
1569
1570 cif = malloc(sizeof(*cif), M_CARP, M_WAITOK|M_ZERO);
1571
1572 if (ifpromisc(ifp, 1) != 0)
1573 goto cleanup;
1574
1575 CIF_LOCK_INIT(cif);
1576 cif->cif_ifp = ifp;
1577 TAILQ_INIT(&cif->cif_vrs);
1578
1579 IF_ADDR_WLOCK(ifp);
1580 ifp->if_carp = cif;
1581 if_ref(ifp);
1582 IF_ADDR_WUNLOCK(ifp);
1583
1584 return (cif);
1585
1586 cleanup:
1587 free(cif, M_CARP);
1588
1589 return (NULL);
1590 }
1591
1592 static void
carp_free_if(struct carp_if * cif)1593 carp_free_if(struct carp_if *cif)
1594 {
1595 struct ifnet *ifp = cif->cif_ifp;
1596
1597 CIF_LOCK_ASSERT(cif);
1598 KASSERT(TAILQ_EMPTY(&cif->cif_vrs), ("%s: softc list not empty",
1599 __func__));
1600
1601 IF_ADDR_WLOCK(ifp);
1602 ifp->if_carp = NULL;
1603 IF_ADDR_WUNLOCK(ifp);
1604
1605 CIF_LOCK_DESTROY(cif);
1606
1607 ifpromisc(ifp, 0);
1608 if_rele(ifp);
1609
1610 free(cif, M_CARP);
1611 }
1612
1613 static void
carp_carprcp(struct carpreq * carpr,struct carp_softc * sc,int priv)1614 carp_carprcp(struct carpreq *carpr, struct carp_softc *sc, int priv)
1615 {
1616
1617 CARP_LOCK(sc);
1618 carpr->carpr_state = sc->sc_state;
1619 carpr->carpr_vhid = sc->sc_vhid;
1620 carpr->carpr_advbase = sc->sc_advbase;
1621 carpr->carpr_advskew = sc->sc_advskew;
1622 if (priv)
1623 bcopy(sc->sc_key, carpr->carpr_key, sizeof(carpr->carpr_key));
1624 else
1625 bzero(carpr->carpr_key, sizeof(carpr->carpr_key));
1626 CARP_UNLOCK(sc);
1627 }
1628
1629 int
carp_ioctl(struct ifreq * ifr,u_long cmd,struct thread * td)1630 carp_ioctl(struct ifreq *ifr, u_long cmd, struct thread *td)
1631 {
1632 struct carpreq carpr;
1633 struct ifnet *ifp;
1634 struct carp_softc *sc = NULL;
1635 int error = 0, locked = 0;
1636
1637 if ((error = copyin(ifr->ifr_data, &carpr, sizeof carpr)))
1638 return (error);
1639
1640 ifp = ifunit_ref(ifr->ifr_name);
1641 if (ifp == NULL)
1642 return (ENXIO);
1643
1644 switch (ifp->if_type) {
1645 case IFT_ETHER:
1646 case IFT_L2VLAN:
1647 case IFT_BRIDGE:
1648 case IFT_FDDI:
1649 case IFT_ISO88025:
1650 break;
1651 default:
1652 error = EOPNOTSUPP;
1653 goto out;
1654 }
1655
1656 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
1657 error = EADDRNOTAVAIL;
1658 goto out;
1659 }
1660
1661 switch (cmd) {
1662 case SIOCSVH:
1663 if ((error = priv_check(td, PRIV_NETINET_CARP)))
1664 break;
1665 if (carpr.carpr_vhid <= 0 || carpr.carpr_vhid > CARP_MAXVHID ||
1666 carpr.carpr_advbase < 0 || carpr.carpr_advskew < 0) {
1667 error = EINVAL;
1668 break;
1669 }
1670
1671 if (ifp->if_carp) {
1672 CIF_LOCK(ifp->if_carp);
1673 IFNET_FOREACH_CARP(ifp, sc)
1674 if (sc->sc_vhid == carpr.carpr_vhid)
1675 break;
1676 CIF_UNLOCK(ifp->if_carp);
1677 }
1678 if (sc == NULL) {
1679 sc = carp_alloc(ifp);
1680 if (sc == NULL) {
1681 error = EINVAL; /* XXX: ifpromisc failed */
1682 break;
1683 }
1684
1685 CARP_LOCK(sc);
1686 sc->sc_vhid = carpr.carpr_vhid;
1687 LLADDR(&sc->sc_addr)[0] = 0;
1688 LLADDR(&sc->sc_addr)[1] = 0;
1689 LLADDR(&sc->sc_addr)[2] = 0x5e;
1690 LLADDR(&sc->sc_addr)[3] = 0;
1691 LLADDR(&sc->sc_addr)[4] = 1;
1692 LLADDR(&sc->sc_addr)[5] = sc->sc_vhid;
1693 } else
1694 CARP_LOCK(sc);
1695 locked = 1;
1696 if (carpr.carpr_advbase > 0) {
1697 if (carpr.carpr_advbase > 255 ||
1698 carpr.carpr_advbase < CARP_DFLTINTV) {
1699 error = EINVAL;
1700 break;
1701 }
1702 sc->sc_advbase = carpr.carpr_advbase;
1703 }
1704 if (carpr.carpr_advskew >= 255) {
1705 error = EINVAL;
1706 break;
1707 }
1708 sc->sc_advskew = carpr.carpr_advskew;
1709 if (carpr.carpr_key[0] != '\0') {
1710 bcopy(carpr.carpr_key, sc->sc_key, sizeof(sc->sc_key));
1711 carp_hmac_prepare(sc);
1712 }
1713 if (sc->sc_state != INIT &&
1714 carpr.carpr_state != sc->sc_state) {
1715 switch (carpr.carpr_state) {
1716 case BACKUP:
1717 callout_stop(&sc->sc_ad_tmo);
1718 carp_set_state(sc, BACKUP);
1719 carp_setrun(sc, 0);
1720 carp_delroute(sc);
1721 break;
1722 case MASTER:
1723 carp_master_down_locked(sc);
1724 break;
1725 default:
1726 break;
1727 }
1728 }
1729 break;
1730
1731 case SIOCGVH:
1732 {
1733 int priveleged;
1734
1735 if (carpr.carpr_vhid < 0 || carpr.carpr_vhid > CARP_MAXVHID) {
1736 error = EINVAL;
1737 break;
1738 }
1739 if (carpr.carpr_count < 1) {
1740 error = EMSGSIZE;
1741 break;
1742 }
1743 if (ifp->if_carp == NULL) {
1744 error = ENOENT;
1745 break;
1746 }
1747
1748 priveleged = (priv_check(td, PRIV_NETINET_CARP) == 0);
1749 if (carpr.carpr_vhid != 0) {
1750 CIF_LOCK(ifp->if_carp);
1751 IFNET_FOREACH_CARP(ifp, sc)
1752 if (sc->sc_vhid == carpr.carpr_vhid)
1753 break;
1754 CIF_UNLOCK(ifp->if_carp);
1755 if (sc == NULL) {
1756 error = ENOENT;
1757 break;
1758 }
1759 carp_carprcp(&carpr, sc, priveleged);
1760 error = copyout(&carpr, ifr->ifr_data, sizeof(carpr));
1761 } else {
1762 int i, count;
1763
1764 count = 0;
1765 CIF_LOCK(ifp->if_carp);
1766 IFNET_FOREACH_CARP(ifp, sc)
1767 count++;
1768
1769 if (count > carpr.carpr_count) {
1770 CIF_UNLOCK(ifp->if_carp);
1771 error = EMSGSIZE;
1772 break;
1773 }
1774
1775 i = 0;
1776 IFNET_FOREACH_CARP(ifp, sc) {
1777 carp_carprcp(&carpr, sc, priveleged);
1778 carpr.carpr_count = count;
1779 error = copyout(&carpr, ifr->ifr_data +
1780 (i * sizeof(carpr)), sizeof(carpr));
1781 if (error) {
1782 CIF_UNLOCK(ifp->if_carp);
1783 break;
1784 }
1785 i++;
1786 }
1787 CIF_UNLOCK(ifp->if_carp);
1788 }
1789 break;
1790 }
1791 default:
1792 error = EINVAL;
1793 }
1794
1795 out:
1796 if (locked)
1797 CARP_UNLOCK(sc);
1798 if_rele(ifp);
1799
1800 return (error);
1801 }
1802
1803 static int
carp_get_vhid(struct ifaddr * ifa)1804 carp_get_vhid(struct ifaddr *ifa)
1805 {
1806
1807 if (ifa == NULL || ifa->ifa_carp == NULL)
1808 return (0);
1809
1810 return (ifa->ifa_carp->sc_vhid);
1811 }
1812
1813 int
carp_attach(struct ifaddr * ifa,int vhid)1814 carp_attach(struct ifaddr *ifa, int vhid)
1815 {
1816 struct ifnet *ifp = ifa->ifa_ifp;
1817 struct carp_if *cif = ifp->if_carp;
1818 struct carp_softc *sc;
1819 int index, error;
1820
1821 if (ifp->if_carp == NULL)
1822 return (ENOPROTOOPT);
1823
1824 switch (ifa->ifa_addr->sa_family) {
1825 #ifdef INET
1826 case AF_INET:
1827 #endif
1828 #ifdef INET6
1829 case AF_INET6:
1830 #endif
1831 break;
1832 default:
1833 return (EPROTOTYPE);
1834 }
1835
1836 CIF_LOCK(cif);
1837 IFNET_FOREACH_CARP(ifp, sc)
1838 if (sc->sc_vhid == vhid)
1839 break;
1840 if (sc == NULL) {
1841 CIF_UNLOCK(cif);
1842 return (ENOENT);
1843 }
1844
1845 if (ifa->ifa_carp) {
1846 if (ifa->ifa_carp->sc_vhid != vhid)
1847 carp_detach_locked(ifa);
1848 else {
1849 CIF_UNLOCK(cif);
1850 return (0);
1851 }
1852 }
1853
1854 error = carp_multicast_setup(cif, ifa->ifa_addr->sa_family);
1855 if (error) {
1856 CIF_FREE(cif);
1857 return (error);
1858 }
1859
1860 CARP_LOCK(sc);
1861 index = sc->sc_naddrs + sc->sc_naddrs6 + 1;
1862 if (index > sc->sc_ifasiz / sizeof(struct ifaddr *))
1863 if ((error = carp_grow_ifas(sc)) != 0) {
1864 carp_multicast_cleanup(cif,
1865 ifa->ifa_addr->sa_family);
1866 CARP_UNLOCK(sc);
1867 CIF_FREE(cif);
1868 return (error);
1869 }
1870
1871 switch (ifa->ifa_addr->sa_family) {
1872 #ifdef INET
1873 case AF_INET:
1874 cif->cif_naddrs++;
1875 sc->sc_naddrs++;
1876 break;
1877 #endif
1878 #ifdef INET6
1879 case AF_INET6:
1880 cif->cif_naddrs6++;
1881 sc->sc_naddrs6++;
1882 break;
1883 #endif
1884 }
1885
1886 ifa_ref(ifa);
1887 sc->sc_ifas[index - 1] = ifa;
1888 ifa->ifa_carp = sc;
1889
1890 carp_hmac_prepare(sc);
1891 carp_sc_state(sc);
1892
1893 CARP_UNLOCK(sc);
1894 CIF_UNLOCK(cif);
1895
1896 return (0);
1897 }
1898
1899 void
carp_detach(struct ifaddr * ifa)1900 carp_detach(struct ifaddr *ifa)
1901 {
1902 struct ifnet *ifp = ifa->ifa_ifp;
1903 struct carp_if *cif = ifp->if_carp;
1904
1905 CIF_LOCK(cif);
1906 carp_detach_locked(ifa);
1907 CIF_FREE(cif);
1908 }
1909
1910 static void
carp_detach_locked(struct ifaddr * ifa)1911 carp_detach_locked(struct ifaddr *ifa)
1912 {
1913 struct ifnet *ifp = ifa->ifa_ifp;
1914 struct carp_if *cif = ifp->if_carp;
1915 struct carp_softc *sc = ifa->ifa_carp;
1916 int i, index;
1917
1918 KASSERT(sc != NULL, ("%s: %p not attached", __func__, ifa));
1919
1920 CIF_LOCK_ASSERT(cif);
1921 CARP_LOCK(sc);
1922
1923 /* Shift array. */
1924 index = sc->sc_naddrs + sc->sc_naddrs6;
1925 for (i = 0; i < index; i++)
1926 if (sc->sc_ifas[i] == ifa)
1927 break;
1928 KASSERT(i < index, ("%s: %p no backref", __func__, ifa));
1929 for (; i < index - 1; i++)
1930 sc->sc_ifas[i] = sc->sc_ifas[i+1];
1931 sc->sc_ifas[index - 1] = NULL;
1932
1933 switch (ifa->ifa_addr->sa_family) {
1934 #ifdef INET
1935 case AF_INET:
1936 cif->cif_naddrs--;
1937 sc->sc_naddrs--;
1938 break;
1939 #endif
1940 #ifdef INET6
1941 case AF_INET6:
1942 cif->cif_naddrs6--;
1943 sc->sc_naddrs6--;
1944 break;
1945 #endif
1946 }
1947
1948 carp_ifa_delroute(ifa);
1949 carp_multicast_cleanup(cif, ifa->ifa_addr->sa_family);
1950
1951 ifa->ifa_carp = NULL;
1952 ifa_free(ifa);
1953
1954 carp_hmac_prepare(sc);
1955 carp_sc_state(sc);
1956
1957 if (sc->sc_naddrs == 0 && sc->sc_naddrs6 == 0) {
1958 CARP_UNLOCK(sc);
1959 carp_destroy(sc);
1960 } else
1961 CARP_UNLOCK(sc);
1962 }
1963
1964 static void
carp_set_state(struct carp_softc * sc,int state)1965 carp_set_state(struct carp_softc *sc, int state)
1966 {
1967
1968 CARP_LOCK_ASSERT(sc);
1969
1970 if (sc->sc_state != state) {
1971 const char *carp_states[] = { CARP_STATES };
1972 char subsys[IFNAMSIZ+5];
1973
1974 sc->sc_state = state;
1975
1976 snprintf(subsys, IFNAMSIZ+5, "%u@%s", sc->sc_vhid,
1977 sc->sc_carpdev->if_xname);
1978 devctl_notify("CARP", subsys, carp_states[state], NULL);
1979 }
1980 }
1981
1982 static void
carp_linkstate(struct ifnet * ifp)1983 carp_linkstate(struct ifnet *ifp)
1984 {
1985 struct carp_softc *sc;
1986
1987 CIF_LOCK(ifp->if_carp);
1988 IFNET_FOREACH_CARP(ifp, sc) {
1989 CARP_LOCK(sc);
1990 carp_sc_state(sc);
1991 CARP_UNLOCK(sc);
1992 }
1993 CIF_UNLOCK(ifp->if_carp);
1994 }
1995
1996 static void
carp_sc_state(struct carp_softc * sc)1997 carp_sc_state(struct carp_softc *sc)
1998 {
1999
2000 CARP_LOCK_ASSERT(sc);
2001
2002 if (sc->sc_carpdev->if_link_state != LINK_STATE_UP ||
2003 !(sc->sc_carpdev->if_flags & IFF_UP)) {
2004 callout_stop(&sc->sc_ad_tmo);
2005 #ifdef INET
2006 callout_stop(&sc->sc_md_tmo);
2007 #endif
2008 #ifdef INET6
2009 callout_stop(&sc->sc_md6_tmo);
2010 #endif
2011 carp_set_state(sc, INIT);
2012 carp_setrun(sc, 0);
2013 if (!sc->sc_suppress)
2014 carp_demote_adj(V_carp_ifdown_adj, "interface down");
2015 sc->sc_suppress = 1;
2016 } else {
2017 carp_set_state(sc, INIT);
2018 carp_setrun(sc, 0);
2019 if (sc->sc_suppress)
2020 carp_demote_adj(-V_carp_ifdown_adj, "interface up");
2021 sc->sc_suppress = 0;
2022 }
2023 }
2024
2025 static void
carp_demote_adj(int adj,char * reason)2026 carp_demote_adj(int adj, char *reason)
2027 {
2028 atomic_add_int(&V_carp_demotion, adj);
2029 CARP_LOG("demoted by %d to %d (%s)\n", adj, V_carp_demotion, reason);
2030 taskqueue_enqueue(taskqueue_swi, &carp_sendall_task);
2031 }
2032
2033 static int
carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS)2034 carp_demote_adj_sysctl(SYSCTL_HANDLER_ARGS)
2035 {
2036 int new, error;
2037
2038 new = V_carp_demotion;
2039 error = sysctl_handle_int(oidp, &new, 0, req);
2040 if (error || !req->newptr)
2041 return (error);
2042
2043 carp_demote_adj(new, "sysctl");
2044
2045 return (0);
2046 }
2047
2048 #ifdef INET
2049 extern struct domain inetdomain;
2050 static struct protosw in_carp_protosw = {
2051 .pr_type = SOCK_RAW,
2052 .pr_domain = &inetdomain,
2053 .pr_protocol = IPPROTO_CARP,
2054 .pr_flags = PR_ATOMIC|PR_ADDR,
2055 .pr_input = carp_input,
2056 .pr_output = (pr_output_t *)rip_output,
2057 .pr_ctloutput = rip_ctloutput,
2058 .pr_usrreqs = &rip_usrreqs
2059 };
2060 #endif
2061
2062 #ifdef INET6
2063 extern struct domain inet6domain;
2064 static struct ip6protosw in6_carp_protosw = {
2065 .pr_type = SOCK_RAW,
2066 .pr_domain = &inet6domain,
2067 .pr_protocol = IPPROTO_CARP,
2068 .pr_flags = PR_ATOMIC|PR_ADDR,
2069 .pr_input = carp6_input,
2070 .pr_output = rip6_output,
2071 .pr_ctloutput = rip6_ctloutput,
2072 .pr_usrreqs = &rip6_usrreqs
2073 };
2074 #endif
2075
2076 static void
carp_mod_cleanup(void)2077 carp_mod_cleanup(void)
2078 {
2079
2080 #ifdef INET
2081 if (proto_reg[CARP_INET] == 0) {
2082 (void)ipproto_unregister(IPPROTO_CARP);
2083 pf_proto_unregister(PF_INET, IPPROTO_CARP, SOCK_RAW);
2084 proto_reg[CARP_INET] = -1;
2085 }
2086 carp_iamatch_p = NULL;
2087 #endif
2088 #ifdef INET6
2089 if (proto_reg[CARP_INET6] == 0) {
2090 (void)ip6proto_unregister(IPPROTO_CARP);
2091 pf_proto_unregister(PF_INET6, IPPROTO_CARP, SOCK_RAW);
2092 proto_reg[CARP_INET6] = -1;
2093 }
2094 carp_iamatch6_p = NULL;
2095 carp_macmatch6_p = NULL;
2096 #endif
2097 carp_ioctl_p = NULL;
2098 carp_attach_p = NULL;
2099 carp_detach_p = NULL;
2100 carp_get_vhid_p = NULL;
2101 carp_linkstate_p = NULL;
2102 carp_forus_p = NULL;
2103 carp_output_p = NULL;
2104 carp_demote_adj_p = NULL;
2105 carp_master_p = NULL;
2106 mtx_unlock(&carp_mtx);
2107 taskqueue_drain(taskqueue_swi, &carp_sendall_task);
2108 mtx_destroy(&carp_mtx);
2109 }
2110
2111 static int
carp_mod_load(void)2112 carp_mod_load(void)
2113 {
2114 int err;
2115
2116 mtx_init(&carp_mtx, "carp_mtx", NULL, MTX_DEF);
2117 LIST_INIT(&carp_list);
2118 carp_get_vhid_p = carp_get_vhid;
2119 carp_forus_p = carp_forus;
2120 carp_output_p = carp_output;
2121 carp_linkstate_p = carp_linkstate;
2122 carp_ioctl_p = carp_ioctl;
2123 carp_attach_p = carp_attach;
2124 carp_detach_p = carp_detach;
2125 carp_demote_adj_p = carp_demote_adj;
2126 carp_master_p = carp_master;
2127 #ifdef INET6
2128 carp_iamatch6_p = carp_iamatch6;
2129 carp_macmatch6_p = carp_macmatch6;
2130 proto_reg[CARP_INET6] = pf_proto_register(PF_INET6,
2131 (struct protosw *)&in6_carp_protosw);
2132 if (proto_reg[CARP_INET6]) {
2133 printf("carp: error %d attaching to PF_INET6\n",
2134 proto_reg[CARP_INET6]);
2135 carp_mod_cleanup();
2136 return (proto_reg[CARP_INET6]);
2137 }
2138 err = ip6proto_register(IPPROTO_CARP);
2139 if (err) {
2140 printf("carp: error %d registering with INET6\n", err);
2141 carp_mod_cleanup();
2142 return (err);
2143 }
2144 #endif
2145 #ifdef INET
2146 carp_iamatch_p = carp_iamatch;
2147 proto_reg[CARP_INET] = pf_proto_register(PF_INET, &in_carp_protosw);
2148 if (proto_reg[CARP_INET]) {
2149 printf("carp: error %d attaching to PF_INET\n",
2150 proto_reg[CARP_INET]);
2151 carp_mod_cleanup();
2152 return (proto_reg[CARP_INET]);
2153 }
2154 err = ipproto_register(IPPROTO_CARP);
2155 if (err) {
2156 printf("carp: error %d registering with INET\n", err);
2157 carp_mod_cleanup();
2158 return (err);
2159 }
2160 #endif
2161 return (0);
2162 }
2163
2164 static int
carp_modevent(module_t mod,int type,void * data)2165 carp_modevent(module_t mod, int type, void *data)
2166 {
2167 switch (type) {
2168 case MOD_LOAD:
2169 return carp_mod_load();
2170 /* NOTREACHED */
2171 case MOD_UNLOAD:
2172 mtx_lock(&carp_mtx);
2173 if (LIST_EMPTY(&carp_list))
2174 carp_mod_cleanup();
2175 else {
2176 mtx_unlock(&carp_mtx);
2177 return (EBUSY);
2178 }
2179 break;
2180
2181 default:
2182 return (EINVAL);
2183 }
2184
2185 return (0);
2186 }
2187
2188 static moduledata_t carp_mod = {
2189 "carp",
2190 carp_modevent,
2191 0
2192 };
2193
2194 DECLARE_MODULE(carp, carp_mod, SI_SUB_PROTO_DOMAIN, SI_ORDER_ANY);
2195