mibII_route.c revision 186119
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 1.9 2005/10/06 07:15:00 brandt_h Exp $ 30 * 31 * Routing table 32 */ 33#include "support.h" 34 35#ifdef HAVE_SYS_TREE_H 36#include <sys/tree.h> 37#else 38#include "tree.h" 39#endif 40 41#include "mibII.h" 42#include "mibII_oid.h" 43 44struct sroute { 45 RB_ENTRY(sroute) link; 46 uint32_t ifindex; 47 uint8_t index[13]; 48 uint8_t type; 49 uint8_t proto; 50}; 51RB_HEAD(sroutes, sroute) sroutes = RB_INITIALIZER(&sroutes); 52 53RB_PROTOTYPE(sroutes, sroute, link, sroute_compare); 54 55#define ROUTE_UPDATE_INTERVAL (100 * 60 * 10) /* 10 min */ 56static uint64_t route_tick; 57static u_int route_total; 58 59/* 60 * Compare two routes 61 */ 62static int 63sroute_compare(struct sroute *s1, struct sroute *s2) 64{ 65 66 return (memcmp(s1->index, s2->index, 13)); 67} 68 69static void 70sroute_index_append(struct asn_oid *oid, u_int sub, const struct sroute *s) 71{ 72 int i; 73 74 oid->len = sub + 13; 75 for (i = 0; i < 13; i++) 76 oid->subs[sub + i] = s->index[i]; 77} 78 79#if 0 80static void 81sroute_print(const struct sroute *r) 82{ 83 u_int i; 84 85 for (i = 0; i < 13 - 1; i++) 86 printf("%u.", r->index[i]); 87 printf("%u proto=%u type=%u", r->index[i], r->proto, r->type); 88} 89#endif 90 91/* 92 * process routing message 93 */ 94void 95mib_sroute_process(struct rt_msghdr *rtm, struct sockaddr *gw, 96 struct sockaddr *dst, struct sockaddr *mask) 97{ 98 struct sockaddr_in *in_dst, *in_gw; 99 struct in_addr in_mask; 100 struct mibif *ifp; 101 struct sroute key; 102 struct sroute *r, *r1; 103 in_addr_t ha; 104 105 if (dst == NULL || gw == NULL || dst->sa_family != AF_INET || 106 gw->sa_family != AF_INET) 107 return; 108 109 in_dst = (struct sockaddr_in *)(void *)dst; 110 in_gw = (struct sockaddr_in *)(void *)gw; 111 112 if (rtm->rtm_flags & RTF_HOST) 113 in_mask.s_addr = 0xffffffff; 114 else if (mask == NULL || mask->sa_len == 0) 115 in_mask.s_addr = 0; 116 else 117 in_mask = ((struct sockaddr_in *)(void *)mask)->sin_addr; 118 119 /* build the index */ 120 ha = ntohl(in_dst->sin_addr.s_addr); 121 key.index[0] = (ha >> 24) & 0xff; 122 key.index[1] = (ha >> 16) & 0xff; 123 key.index[2] = (ha >> 8) & 0xff; 124 key.index[3] = (ha >> 0) & 0xff; 125 126 ha = ntohl(in_mask.s_addr); 127 key.index[4] = (ha >> 24) & 0xff; 128 key.index[5] = (ha >> 16) & 0xff; 129 key.index[6] = (ha >> 8) & 0xff; 130 key.index[7] = (ha >> 0) & 0xff; 131 132 /* ToS */ 133 key.index[8] = 0; 134 135 ha = ntohl(in_gw->sin_addr.s_addr); 136 key.index[9] = (ha >> 24) & 0xff; 137 key.index[10] = (ha >> 16) & 0xff; 138 key.index[11] = (ha >> 8) & 0xff; 139 key.index[12] = (ha >> 0) & 0xff; 140 141 if (rtm->rtm_type == RTM_DELETE) { 142 r = RB_FIND(sroutes, &sroutes, &key); 143 if (r == 0) { 144#ifdef DEBUG_ROUTE 145 syslog(LOG_WARNING, "%s: DELETE: %u.%u.%u.%u " 146 "%u.%u.%u.%u %u %u.%u.%u.%u not found", __func__, 147 key.index[0], key.index[1], key.index[2], 148 key.index[3], key.index[4], key.index[5], 149 key.index[6], key.index[7], key.index[8], 150 key.index[9], key.index[10], key.index[11], 151 key.index[12]); 152#endif 153 return; 154 } 155 RB_REMOVE(sroutes, &sroutes, r); 156 free(r); 157 route_total--; 158#ifdef DEBUG_ROUTE 159 printf("%s: DELETE: %u.%u.%u.%u " 160 "%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__, 161 key.index[0], key.index[1], key.index[2], 162 key.index[3], key.index[4], key.index[5], 163 key.index[6], key.index[7], key.index[8], 164 key.index[9], key.index[10], key.index[11], 165 key.index[12]); 166#endif 167 return; 168 } 169 170 /* GET or ADD */ 171 ifp = NULL; 172 if ((ifp = mib_find_if_sys(rtm->rtm_index)) == NULL) { 173 if (rtm->rtm_type == RTM_ADD) { 174 /* make it a get so the kernel fills the index */ 175 mib_send_rtmsg(rtm, gw, dst, mask); 176 return; 177 } 178 mib_iflist_bad = 1; 179 } 180 181 if ((r = malloc(sizeof(*r))) == NULL) { 182 syslog(LOG_ERR, "%m"); 183 return; 184 } 185 186 memcpy(r->index, key.index, sizeof(r->index)); 187 r->ifindex = (ifp == NULL) ? 0 : ifp->index; 188 189 r->type = (rtm->rtm_flags & RTF_REJECT) ? 2 : 4; 190 191 /* cannot really know, what protocol it runs */ 192 r->proto = (rtm->rtm_flags & RTF_LOCAL) ? 2 : 193 (rtm->rtm_flags & RTF_STATIC) ? 3 : 194 (rtm->rtm_flags & RTF_DYNAMIC) ? 4 : 10; 195 196 r1 = RB_INSERT(sroutes, &sroutes, r); 197 if (r1 != NULL) { 198#ifdef DEBUG_ROUTE 199 syslog(LOG_WARNING, "%s: %u.%u.%u.%u " 200 "%u.%u.%u.%u %u %u.%u.%u.%u duplicate route", __func__, 201 key.index[0], key.index[1], key.index[2], 202 key.index[3], key.index[4], key.index[5], 203 key.index[6], key.index[7], key.index[8], 204 key.index[9], key.index[10], key.index[11], 205 key.index[12]); 206#endif 207 r1->ifindex = r->ifindex; 208 r1->type = r->type; 209 r1->proto = r->proto; 210 free(r); 211 return; 212 } 213 214 route_total++; 215#ifdef DEBUG_ROUTE 216 printf("%s: ADD/GET: %u.%u.%u.%u " 217 "%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__, 218 key.index[0], key.index[1], key.index[2], 219 key.index[3], key.index[4], key.index[5], 220 key.index[6], key.index[7], key.index[8], 221 key.index[9], key.index[10], key.index[11], 222 key.index[12]); 223#endif 224} 225 226int 227mib_fetch_route(void) 228{ 229 u_char *rtab, *next; 230 size_t len; 231 struct sroute *r, *r1; 232 struct rt_msghdr *rtm; 233 struct sockaddr *addrs[RTAX_MAX]; 234 235 if (route_tick != 0 && route_tick + ROUTE_UPDATE_INTERVAL > this_tick) 236 return (0); 237 238 /* 239 * Remove all routes 240 */ 241 r = RB_MIN(sroutes, &sroutes); 242 while (r != NULL) { 243 r1 = RB_NEXT(sroutes, &sroutes, r); 244 RB_REMOVE(sroutes, &sroutes, r); 245 free(r); 246 r = r1; 247 } 248 route_total = 0; 249 250 if ((rtab = mib_fetch_rtab(AF_INET, NET_RT_DUMP, 0, &len)) == NULL) 251 return (-1); 252 253 next = rtab; 254 for (next = rtab; next < rtab + len; next += rtm->rtm_msglen) { 255 rtm = (struct rt_msghdr *)(void *)next; 256 if (rtm->rtm_type != RTM_GET || 257 !(rtm->rtm_flags & RTF_UP)) 258 continue; 259 mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs); 260 261 262 mib_sroute_process(rtm, addrs[RTAX_GATEWAY], addrs[RTAX_DST], 263 addrs[RTAX_NETMASK]); 264 } 265 266#if 0 267 u_int n = 0; 268 r = RB_MIN(sroutes, &sroutes); 269 while (r != NULL) { 270 printf("%u: ", n++); 271 sroute_print(r); 272 printf("\n"); 273 r = RB_NEXT(sroutes, &sroutes, r); 274 } 275#endif 276 free(rtab); 277 route_tick = get_ticks(); 278 279 return (0); 280} 281 282/** 283 * Find a route in the table. 284 */ 285static struct sroute * 286sroute_get(const struct asn_oid *oid, u_int sub) 287{ 288 struct sroute key; 289 int i; 290 291 if (oid->len - sub != 13) 292 return (NULL); 293 for (i = 0; i < 13; i++) 294 key.index[i] = oid->subs[sub + i]; 295 return (RB_FIND(sroutes, &sroutes, &key)); 296} 297 298/** 299 * Find next route in the table. There is no such RB_ macro, so must 300 * dig into the innards of the RB stuff. 301 */ 302static struct sroute * 303sroute_getnext(struct asn_oid *oid, u_int sub) 304{ 305 u_int i; 306 int comp; 307 struct sroute key; 308 struct sroute *best; 309 struct sroute *s; 310 311 /* 312 * We now, that the OID is at least the tableEntry OID. If it is, 313 * the user wants the first route. 314 */ 315 if (oid->len == sub) 316 return (RB_MIN(sroutes, &sroutes)); 317 318 /* 319 * This is also true for any index that consists of zeros and is 320 * shorter than the full index. 321 */ 322 if (oid->len < sub + 13) { 323 for (i = sub; i < oid->len; i++) 324 if (oid->subs[i] != 0) 325 break; 326 if (i == oid->len) 327 return (RB_MIN(sroutes, &sroutes)); 328 329 /* 330 * Now if the index is too short, we fill it with zeros and then 331 * subtract one from the index. We can do this, because we now, 332 * that there is at least one index element that is not zero. 333 */ 334 for (i = oid->len; i < sub + 13; i++) 335 oid->subs[i] = 0; 336 337 for (i = sub + 13 - 1; i >= sub; i--) { 338 if (oid->subs[i] != 0) { 339 oid->subs[i]--; 340 break; 341 } 342 oid->subs[i] = ASN_MAXID; 343 } 344 oid->len = sub + 13; 345 } 346 347 /* build the index */ 348 for (i = sub; i < sub + 13; i++) 349 key.index[i - sub] = oid->subs[i]; 350 351 /* now find the element */ 352 best = NULL; 353 s = RB_ROOT(&sroutes); 354 355 while (s != NULL) { 356 comp = sroute_compare(&key, s); 357 if (comp >= 0) { 358 /* The current element is smaller than what we search. 359 * Forget about it and move to the right subtree. */ 360 s = RB_RIGHT(s, link); 361 continue; 362 } 363 /* the current element is larger than what we search. 364 * forget about the right subtree (its even larger), but 365 * the current element may be what we need. */ 366 if (best == NULL || sroute_compare(s, best) < 0) 367 /* this one's better */ 368 best = s; 369 370 s = RB_LEFT(s, link); 371 } 372 return (best); 373} 374 375/* 376 * Table 377 */ 378int 379op_route_table(struct snmp_context *ctx __unused, struct snmp_value *value, 380 u_int sub, u_int iidx __unused, enum snmp_op op) 381{ 382 struct sroute *r; 383 384 if (mib_fetch_route() == -1) 385 return (SNMP_ERR_GENERR); 386 387 switch (op) { 388 389 case SNMP_OP_GETNEXT: 390 if ((r = sroute_getnext(&value->var, sub)) == NULL) 391 return (SNMP_ERR_NOSUCHNAME); 392 sroute_index_append(&value->var, sub, r); 393 break; 394 395 case SNMP_OP_GET: 396 if ((r = sroute_get(&value->var, sub)) == NULL) 397 return (SNMP_ERR_NOSUCHNAME); 398 break; 399 400 case SNMP_OP_SET: 401 if ((r = sroute_get(&value->var, sub)) == NULL) 402 return (SNMP_ERR_NOSUCHNAME); 403 return (SNMP_ERR_NOT_WRITEABLE); 404 405 case SNMP_OP_ROLLBACK: 406 case SNMP_OP_COMMIT: 407 abort(); 408 409 default: 410 abort(); 411 } 412 413 switch (value->var.subs[sub - 1]) { 414 415 case LEAF_ipCidrRouteDest: 416 value->v.ipaddress[0] = r->index[0]; 417 value->v.ipaddress[1] = r->index[1]; 418 value->v.ipaddress[2] = r->index[2]; 419 value->v.ipaddress[3] = r->index[3]; 420 break; 421 422 case LEAF_ipCidrRouteMask: 423 value->v.ipaddress[0] = r->index[4]; 424 value->v.ipaddress[1] = r->index[5]; 425 value->v.ipaddress[2] = r->index[6]; 426 value->v.ipaddress[3] = r->index[7]; 427 break; 428 429 case LEAF_ipCidrRouteTos: 430 value->v.integer = r->index[8]; 431 break; 432 433 case LEAF_ipCidrRouteNextHop: 434 value->v.ipaddress[0] = r->index[9]; 435 value->v.ipaddress[1] = r->index[10]; 436 value->v.ipaddress[2] = r->index[11]; 437 value->v.ipaddress[3] = r->index[12]; 438 break; 439 440 case LEAF_ipCidrRouteIfIndex: 441 value->v.integer = r->ifindex; 442 break; 443 444 case LEAF_ipCidrRouteType: 445 value->v.integer = r->type; 446 break; 447 448 case LEAF_ipCidrRouteProto: 449 value->v.integer = r->proto; 450 break; 451 452 case LEAF_ipCidrRouteAge: 453 value->v.integer = 0; 454 break; 455 456 case LEAF_ipCidrRouteInfo: 457 value->v.oid = oid_zeroDotZero; 458 break; 459 460 case LEAF_ipCidrRouteNextHopAS: 461 value->v.integer = 0; 462 break; 463 464 case LEAF_ipCidrRouteMetric1: 465 case LEAF_ipCidrRouteMetric2: 466 case LEAF_ipCidrRouteMetric3: 467 case LEAF_ipCidrRouteMetric4: 468 case LEAF_ipCidrRouteMetric5: 469 value->v.integer = -1; 470 break; 471 472 case LEAF_ipCidrRouteStatus: 473 value->v.integer = 1; 474 break; 475 } 476 return (SNMP_ERR_NOERROR); 477} 478 479/* 480 * scalars 481 */ 482int 483op_route(struct snmp_context *ctx __unused, struct snmp_value *value, 484 u_int sub, u_int iidx __unused, enum snmp_op op) 485{ 486 switch (op) { 487 488 case SNMP_OP_GETNEXT: 489 abort(); 490 491 case SNMP_OP_GET: 492 break; 493 494 case SNMP_OP_SET: 495 return (SNMP_ERR_NOT_WRITEABLE); 496 497 case SNMP_OP_ROLLBACK: 498 case SNMP_OP_COMMIT: 499 abort(); 500 } 501 502 if (mib_fetch_route() == -1) 503 return (SNMP_ERR_GENERR); 504 505 switch (value->var.subs[sub - 1]) { 506 507 case LEAF_ipCidrRouteNumber: 508 value->v.uint32 = route_total; 509 break; 510 511 } 512 return (SNMP_ERR_NOERROR); 513} 514 515RB_GENERATE(sroutes, sroute, link, sroute_compare); 516