mibII_route.c revision 150920
1/* 2 * Copyright (c) 2001-2003 3 * Fraunhofer Institute for Open Communication Systems (FhG Fokus). 4 * All rights reserved. 5 * 6 * Author: Harti Brandt <harti@freebsd.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $Begemot: bsnmp/snmp_mibII/mibII_route.c,v 1.7 2005/06/09 12:36:53 brandt_h Exp $ 30 * 31 * Routing table 32 */ 33#include <sys/tree.h> 34#include "mibII.h" 35#include "mibII_oid.h" 36 37struct sroute { 38 RB_ENTRY(sroute) link; 39 uint32_t ifindex; 40 uint8_t index[13]; 41 uint8_t type; 42 uint8_t proto; 43}; 44RB_HEAD(sroutes, sroute) sroutes = RB_INITIALIZER(&sroutes); 45 46RB_PROTOTYPE(sroutes, sroute, link, sroute_compare); 47 48#define ROUTE_UPDATE_INTERVAL (100 * 60 * 10) /* 10 min */ 49static uint64_t route_tick; 50static u_int route_total; 51 52/* 53 * Compare two routes 54 */ 55static int 56sroute_compare(struct sroute *s1, struct sroute *s2) 57{ 58 59 return (memcmp(s1->index, s2->index, 13)); 60} 61 62static void 63sroute_index_append(struct asn_oid *oid, u_int sub, const struct sroute *s) 64{ 65 int i; 66 67 oid->len = sub + 13; 68 for (i = 0; i < 13; i++) 69 oid->subs[sub + i] = s->index[i]; 70} 71 72#if 0 73static void 74sroute_print(const struct sroute *r) 75{ 76 u_int i; 77 78 for (i = 0; i < 13 - 1; i++) 79 printf("%u.", r->index[i]); 80 printf("%u proto=%u type=%u", r->index[i], r->proto, r->type); 81} 82#endif 83 84/* 85 * process routing message 86 */ 87void 88mib_sroute_process(struct rt_msghdr *rtm, struct sockaddr *gw, 89 struct sockaddr *dst, struct sockaddr *mask) 90{ 91 struct sockaddr_in *in_dst, *in_gw; 92 struct in_addr in_mask; 93 struct mibif *ifp; 94 struct sroute key; 95 struct sroute *r, *r1; 96 in_addr_t ha; 97 98 if (dst == NULL || gw == NULL || dst->sa_family != AF_INET || 99 gw->sa_family != AF_INET) 100 return; 101 102 in_dst = (struct sockaddr_in *)(void *)dst; 103 in_gw = (struct sockaddr_in *)(void *)gw; 104 105 if (rtm->rtm_flags & RTF_HOST) 106 in_mask.s_addr = 0xffffffff; 107 else if (mask == NULL || mask->sa_len == 0) 108 in_mask.s_addr = 0; 109 else 110 in_mask = ((struct sockaddr_in *)(void *)mask)->sin_addr; 111 112 /* build the index */ 113 ha = ntohl(in_dst->sin_addr.s_addr); 114 key.index[0] = (ha >> 24) & 0xff; 115 key.index[1] = (ha >> 16) & 0xff; 116 key.index[2] = (ha >> 8) & 0xff; 117 key.index[3] = (ha >> 0) & 0xff; 118 119 ha = ntohl(in_mask.s_addr); 120 key.index[4] = (ha >> 24) & 0xff; 121 key.index[5] = (ha >> 16) & 0xff; 122 key.index[6] = (ha >> 8) & 0xff; 123 key.index[7] = (ha >> 0) & 0xff; 124 125 /* ToS */ 126 key.index[8] = 0; 127 128 ha = ntohl(in_gw->sin_addr.s_addr); 129 key.index[9] = (ha >> 24) & 0xff; 130 key.index[10] = (ha >> 16) & 0xff; 131 key.index[11] = (ha >> 8) & 0xff; 132 key.index[12] = (ha >> 0) & 0xff; 133 134 if (rtm->rtm_type == RTM_DELETE) { 135 r = RB_FIND(sroutes, &sroutes, &key); 136 if (r == 0) { 137#ifdef DEBUG_ROUTE 138 syslog(LOG_WARNING, "%s: DELETE: %u.%u.%u.%u " 139 "%u.%u.%u.%u %u %u.%u.%u.%u not found", __func__, 140 key.index[0], key.index[1], key.index[2], 141 key.index[3], key.index[4], key.index[5], 142 key.index[6], key.index[7], key.index[8], 143 key.index[9], key.index[10], key.index[11], 144 key.index[12]); 145#endif 146 return; 147 } 148 RB_REMOVE(sroutes, &sroutes, r); 149 free(r); 150 route_total--; 151#ifdef DEBUG_ROUTE 152 printf("%s: DELETE: %u.%u.%u.%u " 153 "%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__, 154 key.index[0], key.index[1], key.index[2], 155 key.index[3], key.index[4], key.index[5], 156 key.index[6], key.index[7], key.index[8], 157 key.index[9], key.index[10], key.index[11], 158 key.index[12]); 159#endif 160 return; 161 } 162 163 /* GET or ADD */ 164 ifp = NULL; 165 if ((ifp = mib_find_if_sys(rtm->rtm_index)) == NULL) { 166 if (rtm->rtm_type == RTM_ADD) { 167 /* make it a get so the kernel fills the index */ 168 mib_send_rtmsg(rtm, gw, dst, mask); 169 return; 170 } 171 mib_iflist_bad = 1; 172 } 173 174 if ((r = malloc(sizeof(*r))) == NULL) { 175 syslog(LOG_ERR, "%m"); 176 return; 177 } 178 179 memcpy(r->index, key.index, sizeof(r->index)); 180 r->ifindex = (ifp == NULL) ? 0 : ifp->index; 181 182 r->type = (rtm->rtm_flags & RTF_LLINFO) ? 3 : 183 (rtm->rtm_flags & RTF_REJECT) ? 2 : 4; 184 185 /* cannot really know, what protocol it runs */ 186 r->proto = (rtm->rtm_flags & RTF_LOCAL) ? 2 : 187 (rtm->rtm_flags & RTF_STATIC) ? 3 : 188 (rtm->rtm_flags & RTF_DYNAMIC) ? 4 : 10; 189 190 r1 = RB_INSERT(sroutes, &sroutes, r); 191 if (r1 != NULL) { 192#ifdef DEBUG_ROUTE 193 syslog(LOG_WARNING, "%s: %u.%u.%u.%u " 194 "%u.%u.%u.%u %u %u.%u.%u.%u duplicate route", __func__, 195 key.index[0], key.index[1], key.index[2], 196 key.index[3], key.index[4], key.index[5], 197 key.index[6], key.index[7], key.index[8], 198 key.index[9], key.index[10], key.index[11], 199 key.index[12]); 200#endif 201 r1->ifindex = r->ifindex; 202 r1->type = r->type; 203 r1->proto = r->proto; 204 free(r); 205 return; 206 } 207 208 route_total++; 209#ifdef DEBUG_ROUTE 210 printf("%s: ADD/GET: %u.%u.%u.%u " 211 "%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__, 212 key.index[0], key.index[1], key.index[2], 213 key.index[3], key.index[4], key.index[5], 214 key.index[6], key.index[7], key.index[8], 215 key.index[9], key.index[10], key.index[11], 216 key.index[12]); 217#endif 218} 219 220int 221mib_fetch_route(void) 222{ 223 u_char *rtab, *next; 224 size_t len; 225 struct sroute *r, *r1; 226 struct rt_msghdr *rtm; 227 struct sockaddr *addrs[RTAX_MAX]; 228 229 if (route_tick != 0 && route_tick + ROUTE_UPDATE_INTERVAL > this_tick) 230 return (0); 231 232 /* 233 * Remove all routes 234 */ 235 r = RB_MIN(sroutes, &sroutes); 236 while (r != NULL) { 237 r1 = RB_NEXT(sroutes, &sroutes, r); 238 RB_REMOVE(sroutes, &sroutes, r); 239 free(r); 240 r = r1; 241 } 242 route_total = 0; 243 244 if ((rtab = mib_fetch_rtab(AF_INET, NET_RT_DUMP, 0, &len)) == NULL) 245 return (-1); 246 247 next = rtab; 248 for (next = rtab; next < rtab + len; next += rtm->rtm_msglen) { 249 rtm = (struct rt_msghdr *)(void *)next; 250 if (rtm->rtm_type != RTM_GET || 251 !(rtm->rtm_flags & RTF_UP)) 252 continue; 253 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs); 254 255 256 mib_sroute_process(rtm, addrs[RTAX_GATEWAY], addrs[RTAX_DST], 257 addrs[RTAX_NETMASK]); 258 } 259 260#if 0 261 u_int n = 0; 262 r = RB_MIN(sroutes, &sroutes); 263 while (r != NULL) { 264 printf("%u: ", n++); 265 sroute_print(r); 266 printf("\n"); 267 r = RB_NEXT(sroutes, &sroutes, r); 268 } 269#endif 270 free(rtab); 271 route_tick = get_ticks(); 272 273 return (0); 274} 275 276/** 277 * Find a route in the table. 278 */ 279static struct sroute * 280sroute_get(const struct asn_oid *oid, u_int sub) 281{ 282 struct sroute key; 283 int i; 284 285 if (oid->len - sub != 13) 286 return (NULL); 287 for (i = 0; i < 13; i++) 288 key.index[i] = oid->subs[sub + i]; 289 return (RB_FIND(sroutes, &sroutes, &key)); 290} 291 292/** 293 * Find next route in the table. There is no such RB_ macro, so must 294 * dig into the innards of the RB stuff. 295 */ 296static struct sroute * 297sroute_getnext(struct asn_oid *oid, u_int sub) 298{ 299 u_int i; 300 int comp; 301 struct sroute key; 302 struct sroute *best; 303 struct sroute *s; 304 305 /* 306 * We now, that the OID is at least the tableEntry OID. If it is, 307 * the user wants the first route. 308 */ 309 if (oid->len == sub) 310 return (RB_MIN(sroutes, &sroutes)); 311 312 /* 313 * This is also true for any index that consists of zeros and is 314 * shorter than the full index. 315 */ 316 if (oid->len < sub + 13) { 317 for (i = sub; i < oid->len; i++) 318 if (oid->subs[i] != 0) 319 break; 320 if (i == oid->len) 321 return (RB_MIN(sroutes, &sroutes)); 322 323 /* 324 * Now if the index is too short, we fill it with zeros and then 325 * subtract one from the index. We can do this, because we now, 326 * that there is at least one index element that is not zero. 327 */ 328 for (i = oid->len; i < sub + 13; i++) 329 oid->subs[i] = 0; 330 331 for (i = sub + 13 - 1; i >= sub; i--) { 332 if (oid->subs[i] != 0) { 333 oid->subs[i]--; 334 break; 335 } 336 oid->subs[i] = ASN_MAXID; 337 } 338 oid->len = sub + 13; 339 } 340 341 /* build the index */ 342 for (i = sub; i < sub + 13; i++) 343 key.index[i - sub] = oid->subs[i]; 344 345 /* now find the element */ 346 best = NULL; 347 s = RB_ROOT(&sroutes); 348 349 while (s != NULL) { 350 comp = sroute_compare(&key, s); 351 if (comp >= 0) { 352 /* The current element is smaller than what we search. 353 * Forget about it and move to the right subtree. */ 354 s = RB_RIGHT(s, link); 355 continue; 356 } 357 /* the current element is larger than what we search. 358 * forget about the right subtree (its even larger), but 359 * the current element may be what we need. */ 360 if (best == NULL || sroute_compare(s, best) < 0) 361 /* this one's better */ 362 best = s; 363 364 s = RB_LEFT(s, link); 365 } 366 return (best); 367} 368 369/* 370 * Table 371 */ 372int 373op_route_table(struct snmp_context *ctx __unused, struct snmp_value *value, 374 u_int sub, u_int iidx __unused, enum snmp_op op) 375{ 376 struct sroute *r; 377 378 if (mib_fetch_route() == -1) 379 return (SNMP_ERR_GENERR); 380 381 switch (op) { 382 383 case SNMP_OP_GETNEXT: 384 if ((r = sroute_getnext(&value->var, sub)) == NULL) 385 return (SNMP_ERR_NOSUCHNAME); 386 sroute_index_append(&value->var, sub, r); 387 break; 388 389 case SNMP_OP_GET: 390 if ((r = sroute_get(&value->var, sub)) == NULL) 391 return (SNMP_ERR_NOSUCHNAME); 392 break; 393 394 case SNMP_OP_SET: 395 if ((r = sroute_get(&value->var, sub)) == NULL) 396 return (SNMP_ERR_NOSUCHNAME); 397 return (SNMP_ERR_NOT_WRITEABLE); 398 399 case SNMP_OP_ROLLBACK: 400 case SNMP_OP_COMMIT: 401 abort(); 402 403 default: 404 abort(); 405 } 406 407 switch (value->var.subs[sub - 1]) { 408 409 case LEAF_ipCidrRouteDest: 410 value->v.ipaddress[0] = r->index[0]; 411 value->v.ipaddress[1] = r->index[1]; 412 value->v.ipaddress[2] = r->index[2]; 413 value->v.ipaddress[3] = r->index[3]; 414 break; 415 416 case LEAF_ipCidrRouteMask: 417 value->v.ipaddress[0] = r->index[4]; 418 value->v.ipaddress[1] = r->index[5]; 419 value->v.ipaddress[2] = r->index[6]; 420 value->v.ipaddress[3] = r->index[7]; 421 break; 422 423 case LEAF_ipCidrRouteTos: 424 value->v.integer = r->index[8]; 425 break; 426 427 case LEAF_ipCidrRouteNextHop: 428 value->v.ipaddress[0] = r->index[9]; 429 value->v.ipaddress[1] = r->index[10]; 430 value->v.ipaddress[2] = r->index[11]; 431 value->v.ipaddress[3] = r->index[12]; 432 break; 433 434 case LEAF_ipCidrRouteIfIndex: 435 value->v.integer = r->ifindex; 436 break; 437 438 case LEAF_ipCidrRouteType: 439 value->v.integer = r->type; 440 break; 441 442 case LEAF_ipCidrRouteProto: 443 value->v.integer = r->proto; 444 break; 445 446 case LEAF_ipCidrRouteAge: 447 value->v.integer = 0; 448 break; 449 450 case LEAF_ipCidrRouteInfo: 451 value->v.oid = oid_zeroDotZero; 452 break; 453 454 case LEAF_ipCidrRouteNextHopAS: 455 value->v.integer = 0; 456 break; 457 458 case LEAF_ipCidrRouteMetric1: 459 case LEAF_ipCidrRouteMetric2: 460 case LEAF_ipCidrRouteMetric3: 461 case LEAF_ipCidrRouteMetric4: 462 case LEAF_ipCidrRouteMetric5: 463 value->v.integer = -1; 464 break; 465 466 case LEAF_ipCidrRouteStatus: 467 value->v.integer = 1; 468 break; 469 } 470 return (SNMP_ERR_NOERROR); 471} 472 473/* 474 * scalars 475 */ 476int 477op_route(struct snmp_context *ctx __unused, struct snmp_value *value, 478 u_int sub, u_int iidx __unused, enum snmp_op op) 479{ 480 switch (op) { 481 482 case SNMP_OP_GETNEXT: 483 abort(); 484 485 case SNMP_OP_GET: 486 break; 487 488 case SNMP_OP_SET: 489 return (SNMP_ERR_NOT_WRITEABLE); 490 491 case SNMP_OP_ROLLBACK: 492 case SNMP_OP_COMMIT: 493 abort(); 494 } 495 496 if (mib_fetch_route() == -1) 497 return (SNMP_ERR_GENERR); 498 499 switch (value->var.subs[sub - 1]) { 500 501 case LEAF_ipCidrRouteNumber: 502 value->v.uint32 = route_total; 503 break; 504 505 } 506 return (SNMP_ERR_NOERROR); 507} 508 509RB_GENERATE(sroutes, sroute, link, sroute_compare); 510