1 /* $OpenBSD: interface.c,v 1.9 2012/05/14 10:17:21 sthen Exp $ */ 2 3 /* 4 * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org> 5 * Copyright (c) 2004, 2005, 2008 Esben Norby <norby@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/types.h> 21 #include <sys/ioctl.h> 22 #include <sys/time.h> 23 #include <sys/socket.h> 24 #include <netinet/in.h> 25 #include <arpa/inet.h> 26 #include <net/if.h> 27 #include <net/if_types.h> 28 #include <fcntl.h> 29 #include <ctype.h> 30 #include <err.h> 31 #include <stdio.h> 32 #include <stdlib.h> 33 #include <unistd.h> 34 #include <string.h> 35 #include <event.h> 36 37 #include "ldpd.h" 38 #include "ldp.h" 39 #include "log.h" 40 #include "ldpe.h" 41 42 void if_hello_timer(int, short, void *); 43 void if_start_hello_timer(struct iface *); 44 void if_stop_hello_timer(struct iface *); 45 struct nbr *if_elect(struct nbr *, struct nbr *); 46 47 struct { 48 int state; 49 enum iface_event event; 50 enum iface_action action; 51 int new_state; 52 } iface_fsm[] = { 53 /* current state event that happened action to take resulting state */ 54 {IF_STA_DOWN, IF_EVT_UP, IF_ACT_STRT, IF_STA_ACTIVE}, 55 {IF_STA_LOOPBACK, IF_EVT_DOWN, IF_ACT_NOTHING, IF_STA_DOWN}, 56 {IF_STA_ANY, IF_EVT_DOWN, IF_ACT_RST, IF_STA_DOWN}, 57 {-1, IF_EVT_NOTHING, IF_ACT_NOTHING, 0}, 58 }; 59 60 const char * const if_event_names[] = { 61 "NOTHING", 62 "UP", 63 "DOWN" 64 }; 65 66 const char * const if_action_names[] = { 67 "NOTHING", 68 "START", 69 "RESET" 70 }; 71 72 int 73 if_fsm(struct iface *iface, enum iface_event event) 74 { 75 int old_state; 76 int new_state = 0; 77 int i, ret = 0; 78 79 old_state = iface->state; 80 81 for (i = 0; iface_fsm[i].state != -1; i++) 82 if ((iface_fsm[i].state & old_state) && 83 (iface_fsm[i].event == event)) { 84 new_state = iface_fsm[i].new_state; 85 break; 86 } 87 88 if (iface_fsm[i].state == -1) { 89 /* event outside of the defined fsm, ignore it. */ 90 log_debug("if_fsm: interface %s, " 91 "event %s not expected in state %s", iface->name, 92 if_event_names[event], if_state_name(old_state)); 93 return (0); 94 } 95 96 switch (iface_fsm[i].action) { 97 case IF_ACT_STRT: 98 ret = if_act_start(iface); 99 break; 100 case IF_ACT_RST: 101 ret = if_act_reset(iface); 102 break; 103 case IF_ACT_NOTHING: 104 /* do nothing */ 105 break; 106 } 107 108 if (ret) { 109 log_debug("if_fsm: error changing state for interface %s, " 110 "event %s, state %s", iface->name, if_event_names[event], 111 if_state_name(old_state)); 112 return (-1); 113 } 114 115 if (new_state != 0) 116 iface->state = new_state; 117 118 log_debug("if_fsm: event %s resulted in action %s and changing " 119 "state for interface %s from %s to %s", 120 if_event_names[event], if_action_names[iface_fsm[i].action], 121 iface->name, if_state_name(old_state), if_state_name(iface->state)); 122 123 return (ret); 124 } 125 126 struct iface * 127 if_new(struct kif *kif, struct kif_addr *ka) 128 { 129 struct iface *iface; 130 131 if ((iface = calloc(1, sizeof(*iface))) == NULL) 132 err(1, "if_new: calloc"); 133 134 iface->state = IF_STA_DOWN; 135 136 LIST_INIT(&iface->lde_nbr_list); 137 138 strlcpy(iface->name, kif->ifname, sizeof(iface->name)); 139 140 /* get type */ 141 if (kif->flags & IFF_POINTOPOINT) 142 iface->type = IF_TYPE_POINTOPOINT; 143 if (kif->flags & IFF_BROADCAST && 144 kif->flags & IFF_MULTICAST) 145 iface->type = IF_TYPE_BROADCAST; 146 if (kif->flags & IFF_LOOPBACK) { 147 iface->type = IF_TYPE_POINTOPOINT; 148 iface->state = IF_STA_LOOPBACK; 149 } 150 151 /* get mtu, index and flags */ 152 iface->mtu = kif->mtu; 153 iface->ifindex = kif->ifindex; 154 iface->flags = kif->flags; 155 iface->linkstate = kif->link_state; 156 iface->media_type = kif->media_type; 157 iface->baudrate = kif->baudrate; 158 159 /* set address, mask and p2p addr */ 160 iface->addr = ka->addr; 161 iface->mask = ka->mask; 162 if (kif->flags & IFF_POINTOPOINT) { 163 iface->dst = ka->dstbrd; 164 } 165 166 return (iface); 167 } 168 169 void 170 if_del(struct iface *iface) 171 { 172 log_debug("if_del: interface %s", iface->name); 173 174 if (evtimer_pending(&iface->hello_timer, NULL)) 175 evtimer_del(&iface->hello_timer); 176 177 free(iface); 178 } 179 180 void 181 if_init(struct ldpd_conf *xconf, struct iface *iface) 182 { 183 /* set event handlers for interface */ 184 evtimer_set(&iface->hello_timer, if_hello_timer, iface); 185 186 iface->discovery_fd = xconf->ldp_discovery_socket; 187 } 188 189 /* timers */ 190 /* ARGSUSED */ 191 void 192 if_hello_timer(int fd, short event, void *arg) 193 { 194 struct iface *iface = arg; 195 struct timeval tv; 196 197 send_hello(iface); 198 199 /* reschedule hello_timer */ 200 timerclear(&tv); 201 tv.tv_sec = iface->hello_interval; 202 if (evtimer_add(&iface->hello_timer, &tv) == -1) 203 fatal("if_hello_timer"); 204 } 205 206 void 207 if_start_hello_timer(struct iface *iface) 208 { 209 struct timeval tv; 210 211 timerclear(&tv); 212 tv.tv_sec = iface->hello_interval; 213 if (evtimer_add(&iface->hello_timer, &tv) == -1) 214 fatal("if_start_hello_timer"); 215 } 216 217 void 218 if_stop_hello_timer(struct iface *iface) 219 { 220 if (evtimer_del(&iface->hello_timer) == -1) 221 fatal("if_stop_hello_timer"); 222 } 223 224 /* actions */ 225 int 226 if_act_start(struct iface *iface) 227 { 228 struct in_addr addr; 229 struct timeval now; 230 231 if (!((iface->flags & IFF_UP) && 232 LINK_STATE_IS_UP(iface->linkstate))) { 233 log_debug("if_act_start: interface %s link down", 234 iface->name); 235 return (0); 236 } 237 238 if (iface->media_type == IFT_CARP && iface->passive == 0) { 239 /* force passive mode on carp interfaces */ 240 log_warnx("if_act_start: forcing interface %s to passive", 241 iface->name); 242 iface->passive = 1; 243 } 244 245 gettimeofday(&now, NULL); 246 iface->uptime = now.tv_sec; 247 248 inet_aton(AllRouters, &addr); 249 if (if_join_group(iface, &addr)) 250 return (-1); 251 iface->state = IF_STA_DOWN; 252 253 /* hello timer needs to be started in any case */ 254 if_start_hello_timer(iface); 255 return (0); 256 } 257 258 int 259 if_act_reset(struct iface *iface) 260 { 261 struct in_addr addr; 262 263 inet_aton(AllRouters, &addr); 264 if (if_leave_group(iface, &addr)) { 265 log_warnx("if_act_reset: error leaving group %s, " 266 "interface %s", inet_ntoa(addr), iface->name); 267 } 268 return (0); 269 } 270 271 struct ctl_iface * 272 if_to_ctl(struct iface *iface) 273 { 274 static struct ctl_iface ictl; 275 struct timeval tv, now, res; 276 277 memcpy(ictl.name, iface->name, sizeof(ictl.name)); 278 memcpy(&ictl.addr, &iface->addr, sizeof(ictl.addr)); 279 memcpy(&ictl.mask, &iface->mask, sizeof(ictl.mask)); 280 ictl.rtr_id.s_addr = ldpe_router_id(); 281 ictl.ifindex = iface->ifindex; 282 ictl.state = iface->state; 283 ictl.mtu = iface->mtu; 284 ictl.baudrate = iface->baudrate; 285 ictl.holdtime = iface->holdtime; 286 ictl.hello_interval = iface->hello_interval; 287 ictl.flags = iface->flags; 288 ictl.type = iface->type; 289 ictl.linkstate = iface->linkstate; 290 ictl.mediatype = iface->media_type; 291 ictl.priority = iface->priority; 292 ictl.passive = iface->passive; 293 294 gettimeofday(&now, NULL); 295 if (evtimer_pending(&iface->hello_timer, &tv)) { 296 timersub(&tv, &now, &res); 297 ictl.hello_timer = res.tv_sec; 298 } else 299 ictl.hello_timer = -1; 300 301 if (iface->state != IF_STA_DOWN && 302 iface->uptime != 0) { 303 ictl.uptime = now.tv_sec - iface->uptime; 304 } else 305 ictl.uptime = 0; 306 307 return (&ictl); 308 } 309 310 /* misc */ 311 int 312 if_set_mcast_ttl(int fd, u_int8_t ttl) 313 { 314 if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, 315 (char *)&ttl, sizeof(ttl)) < 0) { 316 log_warn("if_set_mcast_ttl: error setting " 317 "IP_MULTICAST_TTL to %d", ttl); 318 return (-1); 319 } 320 321 return (0); 322 } 323 324 int 325 if_set_tos(int fd, int tos) 326 { 327 if (setsockopt(fd, IPPROTO_IP, IP_TOS, (int *)&tos, sizeof(tos)) < 0) { 328 log_warn("if_set_tos: error setting IP_TOS to 0x%x", tos); 329 return (-1); 330 } 331 332 return (0); 333 } 334 335 int 336 if_set_recvif(int fd, int enable) 337 { 338 if (setsockopt(fd, IPPROTO_IP, IP_RECVIF, &enable, 339 sizeof(enable)) < 0) { 340 log_warn("if_set_recvif: error setting IP_RECVIF"); 341 return (-1); 342 } 343 return (0); 344 } 345 346 void 347 if_set_recvbuf(int fd) 348 { 349 int bsize; 350 351 bsize = 65535; 352 while (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bsize, 353 sizeof(bsize)) == -1) 354 bsize /= 2; 355 } 356 357 int 358 if_set_reuse(int fd, int enable) 359 { 360 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &enable, 361 sizeof(int)) < 0) { 362 log_warn("if_set_reuse: error setting SO_REUSEADDR"); 363 return (-1); 364 } 365 366 return (0); 367 } 368 369 /* 370 * only one JOIN or DROP per interface and address is allowed so we need 371 * to keep track of what is added and removed. 372 */ 373 struct if_group_count { 374 LIST_ENTRY(if_group_count) entry; 375 struct in_addr addr; 376 unsigned int ifindex; 377 int count; 378 }; 379 380 LIST_HEAD(,if_group_count) ifglist = LIST_HEAD_INITIALIZER(ifglist); 381 382 int 383 if_join_group(struct iface *iface, struct in_addr *addr) 384 { 385 struct ip_mreq mreq; 386 struct if_group_count *ifg; 387 388 LIST_FOREACH(ifg, &ifglist, entry) 389 if (iface->ifindex == ifg->ifindex && 390 addr->s_addr == ifg->addr.s_addr) 391 break; 392 if (ifg == NULL) { 393 if ((ifg = calloc(1, sizeof(*ifg))) == NULL) 394 fatal("if_join_group"); 395 ifg->addr.s_addr = addr->s_addr; 396 ifg->ifindex = iface->ifindex; 397 LIST_INSERT_HEAD(&ifglist, ifg, entry); 398 } 399 400 if (ifg->count++ != 0) 401 /* already joined */ 402 return (0); 403 404 mreq.imr_multiaddr.s_addr = addr->s_addr; 405 mreq.imr_interface.s_addr = iface->addr.s_addr; 406 407 if (setsockopt(iface->discovery_fd, IPPROTO_IP, 408 IP_ADD_MEMBERSHIP, (void *)&mreq, sizeof(mreq)) < 0) { 409 log_warn("if_join_group: error IP_ADD_MEMBERSHIP, " 410 "interface %s address %s", iface->name, 411 inet_ntoa(*addr)); 412 return (-1); 413 } 414 return (0); 415 } 416 417 int 418 if_leave_group(struct iface *iface, struct in_addr *addr) 419 { 420 struct ip_mreq mreq; 421 struct if_group_count *ifg; 422 423 LIST_FOREACH(ifg, &ifglist, entry) 424 if (iface->ifindex == ifg->ifindex && 425 addr->s_addr == ifg->addr.s_addr) 426 break; 427 428 /* if interface is not found just try to drop membership */ 429 if (ifg && --ifg->count != 0) 430 /* others still joined */ 431 return (0); 432 433 mreq.imr_multiaddr.s_addr = addr->s_addr; 434 mreq.imr_interface.s_addr = iface->addr.s_addr; 435 436 if (setsockopt(iface->discovery_fd, IPPROTO_IP, 437 IP_DROP_MEMBERSHIP, (void *)&mreq, sizeof(mreq)) < 0) { 438 log_warn("if_leave_group: error IP_DROP_MEMBERSHIP, " 439 "interface %s address %s", iface->name, 440 inet_ntoa(*addr)); 441 return (-1); 442 } 443 444 if (ifg) { 445 LIST_REMOVE(ifg, entry); 446 free(ifg); 447 } 448 return (0); 449 } 450 451 int 452 if_set_mcast(struct iface *iface) 453 { 454 if (setsockopt(iface->discovery_fd, IPPROTO_IP, IP_MULTICAST_IF, 455 &iface->addr.s_addr, sizeof(iface->addr.s_addr)) < 0) { 456 log_debug("if_set_mcast: error setting " 457 "IP_MULTICAST_IF, interface %s", iface->name); 458 return (-1); 459 } 460 461 return (0); 462 } 463 464 int 465 if_set_mcast_loop(int fd) 466 { 467 u_int8_t loop = 0; 468 469 if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, 470 (char *)&loop, sizeof(loop)) < 0) { 471 log_warn("if_set_mcast_loop: error setting IP_MULTICAST_LOOP"); 472 return (-1); 473 } 474 475 return (0); 476 } 477