1 /* $OpenBSD: database.c,v 1.26 2009/01/31 11:44:49 claudio Exp $ */ 2 3 /* 4 * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org> 5 * Copyright (c) 2004, 2005 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/socket.h> 22 #include <netinet/in.h> 23 #include <netinet/in_systm.h> 24 #include <netinet/ip.h> 25 #include <arpa/inet.h> 26 #include <stdlib.h> 27 #include <string.h> 28 #include <unistd.h> 29 30 #include "ospfd.h" 31 #include "ospf.h" 32 #include "log.h" 33 #include "ospfe.h" 34 35 extern struct ospfd_conf *oeconf; 36 37 void db_sum_list_next(struct nbr *); 38 39 /* database description packet handling */ 40 int 41 send_db_description(struct nbr *nbr) 42 { 43 struct sockaddr_in dst; 44 struct db_dscrp_hdr dd_hdr; 45 struct lsa_entry *le, *nle; 46 struct buf *buf; 47 int ret = 0; 48 u_int8_t bits = 0; 49 50 if ((buf = buf_open(nbr->iface->mtu - sizeof(struct ip))) == NULL) 51 fatal("send_db_description"); 52 53 /* OSPF header */ 54 if (gen_ospf_hdr(buf, nbr->iface, PACKET_TYPE_DD)) 55 goto fail; 56 57 /* reserve space for database description header */ 58 if (buf_reserve(buf, sizeof(dd_hdr)) == NULL) 59 goto fail; 60 61 switch (nbr->state) { 62 case NBR_STA_DOWN: 63 case NBR_STA_ATTEMPT: 64 case NBR_STA_INIT: 65 case NBR_STA_2_WAY: 66 case NBR_STA_SNAP: 67 log_debug("send_db_description: cannot send packet in state %s," 68 " neighbor ID %s", nbr_state_name(nbr->state), 69 inet_ntoa(nbr->id)); 70 ret = -1; 71 goto done; 72 case NBR_STA_XSTRT: 73 bits |= OSPF_DBD_MS | OSPF_DBD_M | OSPF_DBD_I; 74 nbr->dd_more = 1; 75 break; 76 case NBR_STA_XCHNG: 77 if (nbr->dd_master) 78 bits |= OSPF_DBD_MS; 79 else 80 bits &= ~OSPF_DBD_MS; 81 82 if (TAILQ_EMPTY(&nbr->db_sum_list)) { 83 bits &= ~OSPF_DBD_M; 84 nbr->dd_more = 0; 85 } else { 86 bits |= OSPF_DBD_M; 87 nbr->dd_more = 1; 88 } 89 90 bits &= ~OSPF_DBD_I; 91 92 /* build LSA list, keep space for a possible md5 sum */ 93 for (le = TAILQ_FIRST(&nbr->db_sum_list); le != NULL && 94 buf_left(buf) >= MD5_DIGEST_LENGTH + sizeof(struct lsa_hdr); 95 le = nle) { 96 nbr->dd_end = nle = TAILQ_NEXT(le, entry); 97 if (buf_add(buf, le->le_lsa, sizeof(struct lsa_hdr))) 98 goto fail; 99 } 100 break; 101 case NBR_STA_LOAD: 102 case NBR_STA_FULL: 103 if (nbr->dd_master) 104 bits |= OSPF_DBD_MS; 105 else 106 bits &= ~OSPF_DBD_MS; 107 bits &= ~OSPF_DBD_M; 108 bits &= ~OSPF_DBD_I; 109 110 nbr->dd_more = 0; 111 break; 112 default: 113 fatalx("send_db_description: unknown neighbor state"); 114 } 115 116 /* set destination */ 117 dst.sin_family = AF_INET; 118 dst.sin_len = sizeof(struct sockaddr_in); 119 120 switch (nbr->iface->type) { 121 case IF_TYPE_POINTOPOINT: 122 inet_aton(AllSPFRouters, &dst.sin_addr); 123 dd_hdr.iface_mtu = htons(nbr->iface->mtu); 124 break; 125 case IF_TYPE_BROADCAST: 126 dst.sin_addr = nbr->addr; 127 dd_hdr.iface_mtu = htons(nbr->iface->mtu); 128 break; 129 case IF_TYPE_NBMA: 130 case IF_TYPE_POINTOMULTIPOINT: 131 /* XXX not supported */ 132 break; 133 case IF_TYPE_VIRTUALLINK: 134 dst.sin_addr = nbr->iface->dst; 135 dd_hdr.iface_mtu = 0; 136 break; 137 default: 138 fatalx("send_db_description: unknown interface type"); 139 } 140 141 dd_hdr.opts = area_ospf_options(nbr->iface->area); 142 dd_hdr.bits = bits; 143 dd_hdr.dd_seq_num = htonl(nbr->dd_seq_num); 144 145 memcpy(buf_seek(buf, sizeof(struct ospf_hdr), sizeof(dd_hdr)), 146 &dd_hdr, sizeof(dd_hdr)); 147 148 /* update authentication and calculate checksum */ 149 if (auth_gen(buf, nbr->iface)) 150 goto fail; 151 152 /* transmit packet */ 153 ret = send_packet(nbr->iface, buf, &dst); 154 done: 155 buf_free(buf); 156 return (ret); 157 fail: 158 log_warn("send_db_description"); 159 buf_free(buf); 160 return (-1); 161 } 162 163 void 164 recv_db_description(struct nbr *nbr, char *buf, u_int16_t len) 165 { 166 struct db_dscrp_hdr dd_hdr; 167 int dupe = 0; 168 169 if (len < sizeof(dd_hdr)) { 170 log_warnx("recv_db_description: " 171 "bad packet size, neighbor ID %s", inet_ntoa(nbr->id)); 172 return; 173 } 174 memcpy(&dd_hdr, buf, sizeof(dd_hdr)); 175 buf += sizeof(dd_hdr); 176 len -= sizeof(dd_hdr); 177 178 /* db description packet sanity checks */ 179 if (ntohs(dd_hdr.iface_mtu) > nbr->iface->mtu) { 180 log_warnx("recv_db_description: invalid MTU %d sent by " 181 "neighbor ID %s, expected %d", ntohs(dd_hdr.iface_mtu), 182 inet_ntoa(nbr->id), nbr->iface->mtu); 183 return; 184 } 185 186 if (nbr->last_rx_options == dd_hdr.opts && 187 nbr->last_rx_bits == dd_hdr.bits && 188 ntohl(dd_hdr.dd_seq_num) == nbr->dd_seq_num - nbr->dd_master ? 189 1 : 0) { 190 log_debug("recv_db_description: dupe from ID %s", 191 inet_ntoa(nbr->id)); 192 dupe = 1; 193 } 194 195 switch (nbr->state) { 196 case NBR_STA_DOWN: 197 case NBR_STA_ATTEMPT: 198 case NBR_STA_2_WAY: 199 case NBR_STA_SNAP: 200 log_debug("recv_db_description: packet ignored in state %s, " 201 "neighbor ID %s", nbr_state_name(nbr->state), 202 inet_ntoa(nbr->id)); 203 return; 204 case NBR_STA_INIT: 205 /* evaluate dr and bdr after issuing a 2-Way event */ 206 nbr_fsm(nbr, NBR_EVT_2_WAY_RCVD); 207 if_fsm(nbr->iface, IF_EVT_NBR_CHNG); 208 if (nbr->state != NBR_STA_XSTRT) 209 return; 210 /* FALLTHROUGH */ 211 case NBR_STA_XSTRT: 212 if (dupe) 213 return; 214 /* 215 * check bits: either I,M,MS or only M 216 */ 217 if (dd_hdr.bits == (OSPF_DBD_I | OSPF_DBD_M | OSPF_DBD_MS)) { 218 /* if nbr Router ID is larger than own -> slave */ 219 if ((ntohl(nbr->id.s_addr)) > 220 ntohl(ospfe_router_id())) { 221 /* slave */ 222 nbr->dd_master = 0; 223 nbr->dd_seq_num = ntohl(dd_hdr.dd_seq_num); 224 225 /* event negotiation done */ 226 nbr_fsm(nbr, NBR_EVT_NEG_DONE); 227 } 228 } else if (!(dd_hdr.bits & (OSPF_DBD_I | OSPF_DBD_MS))) { 229 /* M only case: we are master */ 230 if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num) { 231 log_warnx("recv_db_description: invalid " 232 "seq num, mine %x his %x", 233 nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num)); 234 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 235 return; 236 } 237 nbr->dd_seq_num++; 238 239 /* event negotiation done */ 240 nbr_fsm(nbr, NBR_EVT_NEG_DONE); 241 242 /* this packet may already have data so pass it on */ 243 if (len > 0) { 244 nbr->dd_pending++; 245 ospfe_imsg_compose_rde(IMSG_DD, nbr->peerid, 246 0, buf, len); 247 } 248 } else { 249 /* ignore packet */ 250 log_debug("recv_db_description: packet ignored in " 251 "state %s (bad flags), neighbor ID %s", 252 nbr_state_name(nbr->state), inet_ntoa(nbr->id)); 253 } 254 break; 255 case NBR_STA_XCHNG: 256 case NBR_STA_LOAD: 257 case NBR_STA_FULL: 258 if (dd_hdr.bits & OSPF_DBD_I || 259 !(dd_hdr.bits & OSPF_DBD_MS) == !nbr->dd_master) { 260 log_warnx("recv_db_description: seq num mismatch, " 261 "bad flags"); 262 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 263 return; 264 } 265 266 if (nbr->last_rx_options != dd_hdr.opts) { 267 log_warnx("recv_db_description: seq num mismatch, " 268 "bad options"); 269 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 270 return; 271 } 272 273 if (dupe) { 274 if (!nbr->dd_master) 275 /* retransmit */ 276 start_db_tx_timer(nbr); 277 return; 278 } 279 280 if (nbr->state != NBR_STA_XCHNG) { 281 log_warnx("recv_db_description: invalid " 282 "seq num, mine %x his %x", 283 nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num)); 284 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 285 return; 286 } 287 288 /* sanity check dd seq number */ 289 if (nbr->dd_master) { 290 /* master */ 291 if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num) { 292 log_warnx("recv_db_description: invalid " 293 "seq num, mine %x his %x", 294 nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num)); 295 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 296 return; 297 } 298 nbr->dd_seq_num++; 299 } else { 300 /* slave */ 301 if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num + 1) { 302 log_warnx("recv_db_description: invalid " 303 "seq num, mine %x his %x", 304 nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num)); 305 nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS); 306 return; 307 } 308 nbr->dd_seq_num = ntohl(dd_hdr.dd_seq_num); 309 } 310 311 /* forward to RDE and let it decide which LSAs to request */ 312 if (len > 0) { 313 nbr->dd_pending++; 314 ospfe_imsg_compose_rde(IMSG_DD, nbr->peerid, 0, 315 buf, len); 316 } 317 318 /* next packet */ 319 db_sum_list_next(nbr); 320 start_db_tx_timer(nbr); 321 322 if (!(dd_hdr.bits & OSPF_DBD_M) && 323 TAILQ_EMPTY(&nbr->db_sum_list)) 324 if (!nbr->dd_master || !nbr->dd_more) 325 nbr_fsm(nbr, NBR_EVT_XCHNG_DONE); 326 break; 327 default: 328 fatalx("recv_db_description: unknown neighbor state"); 329 } 330 331 nbr->last_rx_options = dd_hdr.opts; 332 nbr->last_rx_bits = dd_hdr.bits; 333 } 334 335 void 336 db_sum_list_add(struct nbr *nbr, struct lsa_hdr *lsa) 337 { 338 struct lsa_entry *le; 339 340 if ((le = calloc(1, sizeof(*le))) == NULL) 341 fatal("db_sum_list_add"); 342 343 TAILQ_INSERT_TAIL(&nbr->db_sum_list, le, entry); 344 le->le_lsa = lsa; 345 } 346 347 void 348 db_sum_list_next(struct nbr *nbr) 349 { 350 struct lsa_entry *le; 351 352 while ((le = TAILQ_FIRST(&nbr->db_sum_list)) != nbr->dd_end) { 353 TAILQ_REMOVE(&nbr->db_sum_list, le, entry); 354 free(le->le_lsa); 355 free(le); 356 } 357 } 358 359 void 360 db_sum_list_clr(struct nbr *nbr) 361 { 362 nbr->dd_end = NULL; 363 db_sum_list_next(nbr); 364 } 365 366 /* timers */ 367 /* ARGSUSED */ 368 void 369 db_tx_timer(int fd, short event, void *arg) 370 { 371 struct nbr *nbr = arg; 372 struct timeval tv; 373 374 switch (nbr->state) { 375 case NBR_STA_DOWN: 376 case NBR_STA_ATTEMPT: 377 case NBR_STA_INIT: 378 case NBR_STA_2_WAY: 379 case NBR_STA_SNAP: 380 return ; 381 case NBR_STA_XSTRT: 382 case NBR_STA_XCHNG: 383 case NBR_STA_LOAD: 384 case NBR_STA_FULL: 385 send_db_description(nbr); 386 break; 387 default: 388 log_debug("db_tx_timer: unknown neighbor state, " 389 "neighbor ID %s", inet_ntoa(nbr->id)); 390 break; 391 } 392 393 /* reschedule db_tx_timer but only in master mode */ 394 if (nbr->dd_master) { 395 timerclear(&tv); 396 tv.tv_sec = nbr->iface->rxmt_interval; 397 if (evtimer_add(&nbr->db_tx_timer, &tv) == -1) 398 fatal("db_tx_timer"); 399 } 400 } 401 402 void 403 start_db_tx_timer(struct nbr *nbr) 404 { 405 struct timeval tv; 406 407 if (nbr == nbr->iface->self) 408 return; 409 410 timerclear(&tv); 411 if (evtimer_add(&nbr->db_tx_timer, &tv) == -1) 412 fatal("start_db_tx_timer"); 413 } 414 415 void 416 stop_db_tx_timer(struct nbr *nbr) 417 { 418 if (nbr == nbr->iface->self) 419 return; 420 421 if (evtimer_del(&nbr->db_tx_timer) == -1) 422 fatal("stop_db_tx_timer"); 423 } 424