1 /* $NetBSD: tlv_stack.c,v 1.13 2013/07/31 06:58:23 kefren Exp $ */ 2 3 /*- 4 * Copyright (c) 2010 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Mihai Chelaru <kefren@NetBSD.org> 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <arpa/inet.h> 33 34 #include <netmpls/mpls.h> 35 36 #include <stdio.h> 37 #include <string.h> 38 #include <stdlib.h> 39 40 #include "ldp.h" 41 #include "ldp_errors.h" 42 #include "ldp_peer.h" 43 #include "tlv.h" 44 #include "socketops.h" 45 #include "pdu.h" 46 #include "label.h" 47 #include "mpls_interface.h" 48 #include "tlv_stack.h" 49 50 static uint8_t ldp_ceil8(int); 51 52 static uint8_t 53 ldp_ceil8(int x) 54 { 55 if (x % 8 == 0) 56 return x / 8; 57 return x / 8 + 1; 58 } 59 60 int 61 map_label(struct ldp_peer * p, struct fec_tlv * f, struct label_tlv * l) 62 { 63 int n; 64 struct prefix_tlv *pref; 65 union sockunion socktmp; 66 struct label *lbl_check; 67 68 if (ntohs(f->type) != TLV_FEC) { 69 debugp("Invalid FEC TLV !\n"); 70 return LDP_E_BAD_FEC; 71 } 72 if (ntohs(l->type) != TLV_GENERIC_LABEL) { 73 debugp("Invalid LABEL TLV! (0x%.4X)\n", ntohs(l->type)); 74 return LDP_E_BAD_LABEL; 75 } 76 /* 77 * Actually address field length is given only in length field in 78 * bits ! 79 */ 80 81 n = ntohs(f->length); 82 if (!n) 83 return LDP_E_BAD_FEC; 84 85 debugp("Label %u for:\n", ntohl(l->label)); 86 87 pref = (struct prefix_tlv *) (f + 1); 88 memset (&socktmp, 0, sizeof(socktmp)); 89 90 /* 91 * Section 3.4.1 92 * Note that this version of LDP supports the use of multiple FEC 93 * Elements per FEC for the Label Mapping message only. The use of 94 * multiple FEC Elements in other messages is not permitted in this 95 * version, and is a subject for future study. 96 */ 97 98 for (; n > 0; pref = (struct prefix_tlv *) ((unsigned char *) pref + 99 ldp_ceil8(pref->prelen) + TLV_TYPE_LENGTH)) { 100 n -= ldp_ceil8(pref->prelen) + TLV_TYPE_LENGTH; 101 if (ntohs(pref->af) == LDP_AF_INET) { 102 socktmp.sa.sa_family = AF_INET; 103 socktmp.sa.sa_len = sizeof(socktmp.sin); 104 } else if (ntohs(pref->af) == LDP_AF_INET6) { 105 socktmp.sa.sa_family = AF_INET6; 106 socktmp.sa.sa_len = sizeof(socktmp.sin6); 107 } else { 108 warnp("BAD ADDRESS FAMILY (%d) ! (prefix type %d, " 109 "length %d)\n", ntohs(pref->af), pref->type, 110 pref->prelen); 111 return LDP_E_BAD_AF; 112 } 113 switch(pref->type) { 114 case FEC_PREFIX: 115 case FEC_HOST: 116 if (socktmp.sa.sa_family == AF_INET) 117 memcpy(&socktmp.sin.sin_addr, &pref->prefix, 118 ldp_ceil8(pref->prelen)); 119 else 120 memcpy(&socktmp.sin6.sin6_addr, &pref->prefix, 121 ldp_ceil8(pref->prelen)); 122 warnp("Prefix/Host add from %s: %s/%d\n", 123 inet_ntoa(p->ldp_id), satos(&socktmp.sa), 124 pref->prelen); 125 126 ldp_peer_add_mapping(p, &socktmp.sa, pref->prelen, 127 ntohl(l->label)); 128 129 /* Try to change RIB only if label is installed */ 130 lbl_check = label_get_by_prefix(&socktmp.sa, 131 pref->prelen); 132 if (lbl_check != NULL && lbl_check->p == p) { 133 lbl_check->label = ntohl(l->label); 134 mpls_add_label(lbl_check); 135 } else 136 warnp("[map_label] lbl check failed: %s\n", 137 lbl_check == NULL ? "(null)" : 138 lbl_check->p == NULL ? "(null peer)" : 139 inet_ntoa(lbl_check->p->ldp_id)); 140 break; 141 case FEC_WILDCARD: 142 fatalp("LDP: Wildcard add from peer %s\n", 143 satos(p->address)); 144 return LDP_E_BAD_FEC; 145 default: 146 fatalp("Unknown FEC type %d\n", pref->type); 147 return LDP_E_BAD_FEC; 148 } 149 } 150 151 return LDP_E_OK; 152 } 153 154 int 155 withdraw_label(struct ldp_peer * p, struct fec_tlv * f) 156 { 157 int n; 158 struct prefix_tlv *pref; 159 union sockunion socktmp; 160 struct label *lab; 161 162 if (ntohs(f->type) != TLV_FEC) { 163 debugp("Invalid FEC TLV !\n"); 164 return LDP_E_BAD_FEC; 165 } 166 n = ntohs(f->length); 167 if (!n) 168 return LDP_E_BAD_FEC; 169 170 pref = (struct prefix_tlv *) & f[1]; 171 172 memset(&socktmp, 0, sizeof(socktmp)); 173 if (ntohs(pref->af) == LDP_AF_INET) { 174 socktmp.sa.sa_family = AF_INET; 175 socktmp.sa.sa_len = sizeof(socktmp.sin); 176 } else if (ntohs(pref->af) != LDP_AF_INET6) { 177 socktmp.sa.sa_family = AF_INET6; 178 socktmp.sa.sa_len = sizeof(socktmp.sin6); 179 } else { 180 warnp("WITHDRAW: Bad AF (%d)! (prefix type %d, length %d)\n", 181 ntohs(pref->af), pref->type, pref->prelen); 182 return LDP_E_BAD_AF; 183 } 184 switch(pref->type) { 185 case FEC_PREFIX: 186 case FEC_HOST: 187 if (socktmp.sa.sa_family == AF_INET) 188 memcpy(&socktmp.sin.sin_addr, &pref->prefix, 189 ldp_ceil8(pref->prelen)); 190 else 191 memcpy(&socktmp.sin6.sin6_addr, &pref->prefix, 192 ldp_ceil8(pref->prelen)); 193 debugp("Prefix/Host withdraw: %s/%d\n", satos(&socktmp.sa), 194 pref->prelen); 195 196 /* Delete mapping */ 197 ldp_peer_delete_mapping(p, &socktmp.sa, pref->prelen); 198 199 /* Get label, see if we're pointing to this peer 200 * if so, send withdraw, reattach IP route and announce 201 * POP Label 202 */ 203 lab = label_get_by_prefix(&socktmp.sa, pref->prelen); 204 if (lab && lab->p == p) { 205 label_reattach_route(lab, REATT_INET_CHANGE); 206 announce_label_change(lab); /* binding has changed */ 207 } 208 break; 209 case FEC_WILDCARD: 210 fatalp("LDP neighbour %s: Wildcard withdraw !!!\n", 211 satos(p->address)); 212 ldp_peer_delete_all_mappings(p); 213 label_reattach_all_peer_labels(p, REATT_INET_CHANGE); 214 break; 215 default: 216 fatalp("Unknown FEC type %d\n", pref->type); 217 return LDP_E_BAD_FEC; 218 } 219 220 return LDP_E_OK; 221 } 222 223 224 /* 225 * In case of label withdraw, reuse the same buffer to send label release 226 * Simply replace type and message id 227 */ 228 void 229 prepare_release(struct tlv * v) 230 { 231 struct label_map_tlv *t; 232 233 t = (struct label_map_tlv *) v; 234 235 t->type = htons(LDP_LABEL_RELEASE); 236 t->messageid = htonl(get_message_id()); 237 } 238 239 /* Sends a label mapping */ 240 void 241 send_label_tlv(const struct ldp_peer * peer, const struct sockaddr * addr, 242 uint8_t prefixlen, uint32_t label, const struct label_request_tlv *lrt) 243 { 244 struct label_map_tlv *lmt; 245 struct fec_tlv *fec; 246 struct prefix_tlv *p; 247 struct label_tlv *l; 248 249 debugp("SENDING LABEL TLV %s TO %s\n", satos(addr), 250 inet_ntoa(peer->ldp_id)); 251 252 /* 253 * Ok, so we have label map tlv that contains fec tlvs and label tlv 254 * but fec tlv contains prefix or host tlvs and prefix or host tlvs 255 * contains the network. After that we may have optional parameters 256 * Got it ? 257 */ 258 259 lmt = calloc(1, 260 sizeof(struct label_map_tlv) + 261 sizeof(struct fec_tlv) + 262 sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 263 ldp_ceil8(prefixlen) + 264 sizeof(struct label_tlv) + 265 /* Label request optional parameter */ 266 (lrt != NULL ? sizeof(struct label_request_tlv) : 0) ); 267 268 if (!lmt) { 269 fatalp("send_label_tlv: calloc problem\n"); 270 return; 271 } 272 273 lmt->type = htons(LDP_LABEL_MAPPING); 274 lmt->length = htons(sizeof(struct label_map_tlv) - TLV_TYPE_LENGTH 275 + sizeof(struct fec_tlv) 276 + sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 277 ldp_ceil8(prefixlen) 278 + sizeof(struct label_tlv) + 279 + (lrt != NULL ? sizeof(struct label_request_tlv) : 0)); 280 lmt->messageid = htonl(get_message_id()); 281 282 /* FEC TLV */ 283 fec = (struct fec_tlv *) & lmt[1]; 284 fec->type = htons(TLV_FEC); 285 fec->length = htons(sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 286 ldp_ceil8(prefixlen)); 287 288 /* Now let's do the even a dirtier job: PREFIX TLV */ 289 p = (struct prefix_tlv *) & fec[1]; 290 /* 291 * RFC5036 obsoletes FEC_HOST 292 * 293 * if (prefixlen == 32) p->type = FEC_HOST; else 294 */ 295 p->type = FEC_PREFIX; 296 p->af = htons(LDP_AF_INET); 297 p->prelen = prefixlen; 298 memcpy(&p->prefix, & ((const struct sockaddr_in*)addr)->sin_addr, 299 ldp_ceil8(prefixlen)); 300 301 /* LABEL TLV */ 302 l = (struct label_tlv *) ((unsigned char *) p + 303 sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 304 ldp_ceil8(prefixlen)); 305 l->type = htons(TLV_GENERIC_LABEL); 306 l->length = htons(sizeof(l->label)); 307 l->label = htonl(label); 308 309 /* Label request optional parameter */ 310 if (lrt) 311 memcpy(((char*)l) + TLV_TYPE_LENGTH + ntohs(l->length), 312 lrt, htons(lrt->length) + TLV_TYPE_LENGTH); 313 314 /* Wow, seems we're ready */ 315 send_tlv(peer, (struct tlv *) lmt); 316 free(lmt); 317 } 318 319 void 320 send_label_tlv_to_all(const struct sockaddr * addr, uint8_t prefixlen, 321 uint32_t label) 322 { 323 struct ldp_peer *p; 324 SLIST_FOREACH(p, &ldp_peer_head, peers) 325 if (p->state == LDP_PEER_ESTABLISHED) 326 send_label_tlv(p, addr, prefixlen, label, NULL); 327 } 328 329 /* 330 * Send all local labels to a peer 331 */ 332 void 333 send_all_bindings(const struct ldp_peer * peer) 334 { 335 struct label *l = NULL; 336 337 while((l = label_get_right(l)) != NULL) 338 send_label_tlv(peer, &l->so_dest.sa, 339 from_union_to_cidr(&l->so_pref), l->binding, NULL); 340 341 } 342 343 /* Sends a label WITHDRAW */ 344 void 345 send_withdraw_tlv(const struct ldp_peer * peer, const struct sockaddr * addr, 346 uint8_t prefixlen) 347 { 348 struct label_map_tlv *lmt; 349 struct fec_tlv *fec; 350 struct prefix_tlv *p; 351 352 /* 353 * Ok, so we have label map tlv that contains fec tlvs but fec tlv 354 * contains prefix or host tlvs and prefix or host tlvs contains the 355 * network. Yes, we don't have to announce label here 356 */ 357 358 lmt = malloc(sizeof(struct label_map_tlv) 359 + sizeof(struct fec_tlv) 360 + sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 361 ldp_ceil8(prefixlen)); 362 363 if (!lmt) { 364 fatalp("send_withdraw_tlv: malloc problem\n"); 365 return; 366 } 367 368 lmt->type = htons(LDP_LABEL_WITHDRAW); 369 lmt->length = htons(sizeof(struct label_map_tlv) - TLV_TYPE_LENGTH 370 + sizeof(struct fec_tlv) 371 + sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 372 ldp_ceil8(prefixlen)); 373 lmt->messageid = htonl(get_message_id()); 374 375 /* FEC TLV */ 376 fec = (struct fec_tlv *) & lmt[1]; 377 fec->type = htons(TLV_FEC); 378 fec->length = htons(sizeof(struct fec_tlv) - TLV_TYPE_LENGTH 379 + sizeof(struct prefix_tlv) - sizeof(struct in_addr) + 380 ldp_ceil8(prefixlen)); 381 382 /* Now the even dirtier job: PREFIX TLV */ 383 p = (struct prefix_tlv *) & fec[1]; 384 /* 385 * RFC5036 obsoletes FEC_HOST 386 * 387 * if (prefixlen == 32) p->type = FEC_HOST; else 388 */ 389 p->type = FEC_PREFIX; 390 p->af = htons(LDP_AF_INET); 391 p->prelen = prefixlen; 392 memcpy(&p->prefix, addr, ldp_ceil8(prefixlen)); 393 394 /* Wow, seems we're ready */ 395 send_tlv(peer, (struct tlv *) lmt); 396 free(lmt); 397 } 398 399 void 400 send_withdraw_tlv_to_all(const struct sockaddr * addr, uint8_t prefixlen) 401 { 402 struct ldp_peer *p; 403 SLIST_FOREACH(p, &ldp_peer_head, peers) 404 if (p->state == LDP_PEER_ESTABLISHED) 405 send_withdraw_tlv(p, addr, prefixlen); 406 } 407 408 int 409 request_respond(const struct ldp_peer *p, const struct label_map_tlv *lmt, 410 const struct fec_tlv *fec) 411 { 412 const struct prefix_tlv *pref; 413 union sockunion socktmp; 414 struct label *lab; 415 struct label_request_tlv lrm; 416 417 if (ntohs(fec->type) != TLV_FEC || fec->length == 0) { 418 debugp("Invalid FEC TLV !\n"); 419 return LDP_E_BAD_FEC; 420 } 421 pref = (const struct prefix_tlv *) (fec + 1); 422 423 memset(&socktmp, 0, sizeof(socktmp)); 424 if (ntohs(pref->af) == LDP_AF_INET) { 425 socktmp.sa.sa_family = AF_INET; 426 socktmp.sa.sa_len = sizeof(socktmp.sin); 427 } else if (ntohs(pref->af) == LDP_AF_INET6) { 428 socktmp.sa.sa_family = AF_INET6; 429 socktmp.sa.sa_len = sizeof(socktmp.sin6); 430 } else { 431 debugp("request_respond: Bad address family\n"); 432 return LDP_E_BAD_AF; 433 } 434 435 switch (pref->type) { 436 case FEC_PREFIX: 437 case FEC_HOST: 438 439 if (socktmp.sa.sa_family == AF_INET) 440 memcpy(&socktmp.sin.sin_addr, &pref->prefix, 441 ldp_ceil8(pref->prelen)); 442 else /* AF_INET6 */ 443 memcpy(&socktmp.sin6.sin6_addr, &pref->prefix, 444 ldp_ceil8(pref->prelen)); 445 debugp("Prefix/Host request: %s/%d\n", satos(&socktmp.sa), 446 pref->prelen); 447 448 lab = label_get_by_prefix(&socktmp.sa, pref->prelen); 449 if (!lab) 450 return LDP_E_NO_SUCH_ROUTE; 451 lrm.type = htons(TLV_LABEL_REQUEST); 452 /* XXX - use sizeof */ 453 lrm.length = htons(socktmp.sa.sa_family == AF_INET ? 4 : 16); 454 lrm.messageid = lmt->messageid; 455 send_label_tlv(p, &socktmp.sa, pref->prelen, lab->binding, 456 &lrm); 457 break; 458 459 case FEC_WILDCARD: 460 /* 461 * Section 3.4.1 462 * To be used only in the Label Withdraw and Label Release 463 */ 464 /* Fallthrough */ 465 default: 466 467 fatalp("Invalid FEC type\n"); 468 return LDP_E_BAD_FEC; 469 } 470 return LDP_E_OK; 471 } 472