1 /* 2 * Copyright (c) 1980, 1986, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)route.c 8.3 (Berkeley) 1/9/95 34 * $FreeBSD: src/sys/net/route.c,v 1.59.2.10 2003/01/17 08:04:00 ru Exp $ 35 * $DragonFly: src/sys/net/route.c,v 1.6 2003/08/26 20:49:47 rob Exp $ 36 */ 37 38 #include "opt_inet.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/malloc.h> 43 #include <sys/mbuf.h> 44 #include <sys/socket.h> 45 #include <sys/domain.h> 46 #include <sys/kernel.h> 47 48 #include <net/if.h> 49 #include <net/route.h> 50 51 #include <netinet/in.h> 52 #include <net/ip_mroute/ip_mroute.h> 53 54 #define SA(p) ((struct sockaddr *)(p)) 55 56 struct route_cb route_cb; 57 static struct rtstat rtstat; 58 struct radix_node_head *rt_tables[AF_MAX+1]; 59 60 static int rttrash; /* routes not in table but not freed */ 61 62 static void rt_maskedcopy (struct sockaddr *, 63 struct sockaddr *, struct sockaddr *); 64 static void rtable_init (void **); 65 66 static void 67 rtable_init(table) 68 void **table; 69 { 70 struct domain *dom; 71 for (dom = domains; dom; dom = dom->dom_next) 72 if (dom->dom_rtattach) 73 dom->dom_rtattach(&table[dom->dom_family], 74 dom->dom_rtoffset); 75 } 76 77 void 78 route_init() 79 { 80 rn_init(); /* initialize all zeroes, all ones, mask table */ 81 rtable_init((void **)rt_tables); 82 } 83 84 /* 85 * Packet routing routines. 86 */ 87 void 88 rtalloc(ro) 89 struct route *ro; 90 { 91 rtalloc_ign(ro, 0UL); 92 } 93 94 void 95 rtalloc_ign(ro, ignore) 96 struct route *ro; 97 u_long ignore; 98 { 99 struct rtentry *rt; 100 int s; 101 102 if ((rt = ro->ro_rt) != NULL) { 103 if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP) 104 return; 105 /* XXX - We are probably always at splnet here already. */ 106 s = splnet(); 107 RTFREE(rt); 108 ro->ro_rt = NULL; 109 splx(s); 110 } 111 ro->ro_rt = rtalloc1(&ro->ro_dst, 1, ignore); 112 } 113 114 /* 115 * Look up the route that matches the address given 116 * Or, at least try.. Create a cloned route if needed. 117 */ 118 struct rtentry * 119 rtalloc1(dst, report, ignflags) 120 struct sockaddr *dst; 121 int report; 122 u_long ignflags; 123 { 124 struct radix_node_head *rnh = rt_tables[dst->sa_family]; 125 struct rtentry *rt; 126 struct radix_node *rn; 127 struct rtentry *newrt = 0; 128 struct rt_addrinfo info; 129 u_long nflags; 130 int s = splnet(), err = 0, msgtype = RTM_MISS; 131 132 /* 133 * Look up the address in the table for that Address Family 134 */ 135 if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) && 136 ((rn->rn_flags & RNF_ROOT) == 0)) { 137 /* 138 * If we find it and it's not the root node, then 139 * get a refernce on the rtentry associated. 140 */ 141 newrt = rt = (struct rtentry *)rn; 142 nflags = rt->rt_flags & ~ignflags; 143 if (report && (nflags & (RTF_CLONING | RTF_PRCLONING))) { 144 /* 145 * We are apparently adding (report = 0 in delete). 146 * If it requires that it be cloned, do so. 147 * (This implies it wasn't a HOST route.) 148 */ 149 err = rtrequest(RTM_RESOLVE, dst, SA(0), 150 SA(0), 0, &newrt); 151 if (err) { 152 /* 153 * If the cloning didn't succeed, maybe 154 * what we have will do. Return that. 155 */ 156 newrt = rt; 157 rt->rt_refcnt++; 158 goto miss; 159 } 160 if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) { 161 /* 162 * If the new route specifies it be 163 * externally resolved, then go do that. 164 */ 165 msgtype = RTM_RESOLVE; 166 goto miss; 167 } 168 /* Inform listeners of the new route. */ 169 bzero(&info, sizeof(info)); 170 info.rti_info[RTAX_DST] = rt_key(rt); 171 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 172 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 173 if (rt->rt_ifp != NULL) { 174 info.rti_info[RTAX_IFP] = 175 TAILQ_FIRST(&rt->rt_ifp->if_addrhead)->ifa_addr; 176 info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr; 177 } 178 rt_missmsg(RTM_ADD, &info, rt->rt_flags, 0); 179 } else 180 rt->rt_refcnt++; 181 } else { 182 /* 183 * Either we hit the root or couldn't find any match, 184 * Which basically means 185 * "caint get there frm here" 186 */ 187 rtstat.rts_unreach++; 188 miss: if (report) { 189 /* 190 * If required, report the failure to the supervising 191 * Authorities. 192 * For a delete, this is not an error. (report == 0) 193 */ 194 bzero((caddr_t)&info, sizeof(info)); 195 info.rti_info[RTAX_DST] = dst; 196 rt_missmsg(msgtype, &info, 0, err); 197 } 198 } 199 splx(s); 200 return (newrt); 201 } 202 203 /* 204 * Remove a reference count from an rtentry. 205 * If the count gets low enough, take it out of the routing table 206 */ 207 void 208 rtfree(rt) 209 struct rtentry *rt; 210 { 211 /* 212 * find the tree for that address family 213 */ 214 struct radix_node_head *rnh = 215 rt_tables[rt_key(rt)->sa_family]; 216 struct ifaddr *ifa; 217 218 if (rt == 0 || rnh == 0) 219 panic("rtfree"); 220 221 /* 222 * decrement the reference count by one and if it reaches 0, 223 * and there is a close function defined, call the close function 224 */ 225 rt->rt_refcnt--; 226 if(rnh->rnh_close && rt->rt_refcnt == 0) { 227 rnh->rnh_close((struct radix_node *)rt, rnh); 228 } 229 230 /* 231 * If we are no longer "up" (and ref == 0) 232 * then we can free the resources associated 233 * with the route. 234 */ 235 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) { 236 if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 237 panic ("rtfree 2"); 238 /* 239 * the rtentry must have been removed from the routing table 240 * so it is represented in rttrash.. remove that now. 241 */ 242 rttrash--; 243 244 #ifdef DIAGNOSTIC 245 if (rt->rt_refcnt < 0) { 246 printf("rtfree: %p not freed (neg refs)\n", rt); 247 return; 248 } 249 #endif 250 251 /* 252 * release references on items we hold them on.. 253 * e.g other routes and ifaddrs. 254 */ 255 if((ifa = rt->rt_ifa)) 256 IFAFREE(ifa); 257 if (rt->rt_parent) { 258 RTFREE(rt->rt_parent); 259 } 260 261 /* 262 * The key is separatly alloc'd so free it (see rt_setgate()). 263 * This also frees the gateway, as they are always malloc'd 264 * together. 265 */ 266 Free(rt_key(rt)); 267 268 /* 269 * and the rtentry itself of course 270 */ 271 Free(rt); 272 } 273 } 274 275 void 276 ifafree(ifa) 277 struct ifaddr *ifa; 278 { 279 if (ifa == NULL) 280 panic("ifafree"); 281 if (ifa->ifa_refcnt == 0) 282 free(ifa, M_IFADDR); 283 else 284 ifa->ifa_refcnt--; 285 } 286 287 /* 288 * Force a routing table entry to the specified 289 * destination to go through the given gateway. 290 * Normally called as a result of a routing redirect 291 * message from the network layer. 292 * 293 * N.B.: must be called at splnet 294 * 295 */ 296 void 297 rtredirect(dst, gateway, netmask, flags, src, rtp) 298 struct sockaddr *dst, *gateway, *netmask, *src; 299 int flags; 300 struct rtentry **rtp; 301 { 302 struct rtentry *rt; 303 int error = 0; 304 short *stat = 0; 305 struct rt_addrinfo info; 306 struct ifaddr *ifa; 307 308 /* verify the gateway is directly reachable */ 309 if ((ifa = ifa_ifwithnet(gateway)) == 0) { 310 error = ENETUNREACH; 311 goto out; 312 } 313 rt = rtalloc1(dst, 0, 0UL); 314 /* 315 * If the redirect isn't from our current router for this dst, 316 * it's either old or wrong. If it redirects us to ourselves, 317 * we have a routing loop, perhaps as a result of an interface 318 * going down recently. 319 */ 320 #define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0) 321 if (!(flags & RTF_DONE) && rt && 322 (!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) 323 error = EINVAL; 324 else if (ifa_ifwithaddr(gateway)) 325 error = EHOSTUNREACH; 326 if (error) 327 goto done; 328 /* 329 * Create a new entry if we just got back a wildcard entry 330 * or the the lookup failed. This is necessary for hosts 331 * which use routing redirects generated by smart gateways 332 * to dynamically build the routing tables. 333 */ 334 if ((rt == 0) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2)) 335 goto create; 336 /* 337 * Don't listen to the redirect if it's 338 * for a route to an interface. 339 */ 340 if (rt->rt_flags & RTF_GATEWAY) { 341 if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) { 342 /* 343 * Changing from route to net => route to host. 344 * Create new route, rather than smashing route to net. 345 */ 346 create: 347 if (rt) 348 rtfree(rt); 349 flags |= RTF_GATEWAY | RTF_DYNAMIC; 350 bzero((caddr_t)&info, sizeof(info)); 351 info.rti_info[RTAX_DST] = dst; 352 info.rti_info[RTAX_GATEWAY] = gateway; 353 info.rti_info[RTAX_NETMASK] = netmask; 354 info.rti_ifa = ifa; 355 info.rti_flags = flags; 356 rt = NULL; 357 error = rtrequest1(RTM_ADD, &info, &rt); 358 if (rt != NULL) 359 flags = rt->rt_flags; 360 stat = &rtstat.rts_dynamic; 361 } else { 362 /* 363 * Smash the current notion of the gateway to 364 * this destination. Should check about netmask!!! 365 */ 366 rt->rt_flags |= RTF_MODIFIED; 367 flags |= RTF_MODIFIED; 368 stat = &rtstat.rts_newgateway; 369 /* 370 * add the key and gateway (in one malloc'd chunk). 371 */ 372 rt_setgate(rt, rt_key(rt), gateway); 373 } 374 } else 375 error = EHOSTUNREACH; 376 done: 377 if (rt) { 378 if (rtp && !error) 379 *rtp = rt; 380 else 381 rtfree(rt); 382 } 383 out: 384 if (error) 385 rtstat.rts_badredirect++; 386 else if (stat != NULL) 387 (*stat)++; 388 bzero((caddr_t)&info, sizeof(info)); 389 info.rti_info[RTAX_DST] = dst; 390 info.rti_info[RTAX_GATEWAY] = gateway; 391 info.rti_info[RTAX_NETMASK] = netmask; 392 info.rti_info[RTAX_AUTHOR] = src; 393 rt_missmsg(RTM_REDIRECT, &info, flags, error); 394 } 395 396 /* 397 * Routing table ioctl interface. 398 */ 399 int 400 rtioctl(u_long req, caddr_t data, struct thread *td) 401 { 402 #ifdef INET 403 /* Multicast goop, grrr... */ 404 return mrt_ioctl ? mrt_ioctl(req, data) : EOPNOTSUPP; 405 #else /* INET */ 406 return ENXIO; 407 #endif /* INET */ 408 } 409 410 struct ifaddr * 411 ifa_ifwithroute(flags, dst, gateway) 412 int flags; 413 struct sockaddr *dst, *gateway; 414 { 415 struct ifaddr *ifa; 416 if ((flags & RTF_GATEWAY) == 0) { 417 /* 418 * If we are adding a route to an interface, 419 * and the interface is a pt to pt link 420 * we should search for the destination 421 * as our clue to the interface. Otherwise 422 * we can use the local address. 423 */ 424 ifa = 0; 425 if (flags & RTF_HOST) { 426 ifa = ifa_ifwithdstaddr(dst); 427 } 428 if (ifa == 0) 429 ifa = ifa_ifwithaddr(gateway); 430 } else { 431 /* 432 * If we are adding a route to a remote net 433 * or host, the gateway may still be on the 434 * other end of a pt to pt link. 435 */ 436 ifa = ifa_ifwithdstaddr(gateway); 437 } 438 if (ifa == 0) 439 ifa = ifa_ifwithnet(gateway); 440 if (ifa == 0) { 441 struct rtentry *rt = rtalloc1(gateway, 0, 0UL); 442 if (rt == 0) 443 return (0); 444 rt->rt_refcnt--; 445 if ((ifa = rt->rt_ifa) == 0) 446 return (0); 447 } 448 if (ifa->ifa_addr->sa_family != dst->sa_family) { 449 struct ifaddr *oifa = ifa; 450 ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp); 451 if (ifa == 0) 452 ifa = oifa; 453 } 454 return (ifa); 455 } 456 457 static int rt_fixdelete (struct radix_node *, void *); 458 static int rt_fixchange (struct radix_node *, void *); 459 460 struct rtfc_arg { 461 struct rtentry *rt0; 462 struct radix_node_head *rnh; 463 }; 464 465 /* 466 * Do appropriate manipulations of a routing tree given 467 * all the bits of info needed 468 */ 469 int 470 rtrequest(req, dst, gateway, netmask, flags, ret_nrt) 471 int req, flags; 472 struct sockaddr *dst, *gateway, *netmask; 473 struct rtentry **ret_nrt; 474 { 475 struct rt_addrinfo info; 476 477 bzero((caddr_t)&info, sizeof(info)); 478 info.rti_flags = flags; 479 info.rti_info[RTAX_DST] = dst; 480 info.rti_info[RTAX_GATEWAY] = gateway; 481 info.rti_info[RTAX_NETMASK] = netmask; 482 return rtrequest1(req, &info, ret_nrt); 483 } 484 485 /* 486 * These (questionable) definitions of apparent local variables apply 487 * to the next two functions. XXXXXX!!! 488 */ 489 #define dst info->rti_info[RTAX_DST] 490 #define gateway info->rti_info[RTAX_GATEWAY] 491 #define netmask info->rti_info[RTAX_NETMASK] 492 #define ifaaddr info->rti_info[RTAX_IFA] 493 #define ifpaddr info->rti_info[RTAX_IFP] 494 #define flags info->rti_flags 495 496 int 497 rt_getifa(info) 498 struct rt_addrinfo *info; 499 { 500 struct ifaddr *ifa; 501 int error = 0; 502 503 /* 504 * ifp may be specified by sockaddr_dl 505 * when protocol address is ambiguous. 506 */ 507 if (info->rti_ifp == NULL && ifpaddr != NULL && 508 ifpaddr->sa_family == AF_LINK && 509 (ifa = ifa_ifwithnet(ifpaddr)) != NULL) 510 info->rti_ifp = ifa->ifa_ifp; 511 if (info->rti_ifa == NULL && ifaaddr != NULL) 512 info->rti_ifa = ifa_ifwithaddr(ifaaddr); 513 if (info->rti_ifa == NULL) { 514 struct sockaddr *sa; 515 516 sa = ifaaddr != NULL ? ifaaddr : 517 (gateway != NULL ? gateway : dst); 518 if (sa != NULL && info->rti_ifp != NULL) 519 info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp); 520 else if (dst != NULL && gateway != NULL) 521 info->rti_ifa = ifa_ifwithroute(flags, dst, gateway); 522 else if (sa != NULL) 523 info->rti_ifa = ifa_ifwithroute(flags, sa, sa); 524 } 525 if ((ifa = info->rti_ifa) != NULL) { 526 if (info->rti_ifp == NULL) 527 info->rti_ifp = ifa->ifa_ifp; 528 } else 529 error = ENETUNREACH; 530 return (error); 531 } 532 533 int 534 rtrequest1(req, info, ret_nrt) 535 int req; 536 struct rt_addrinfo *info; 537 struct rtentry **ret_nrt; 538 { 539 int s = splnet(); int error = 0; 540 struct rtentry *rt; 541 struct radix_node *rn; 542 struct radix_node_head *rnh; 543 struct ifaddr *ifa; 544 struct sockaddr *ndst; 545 #define senderr(x) { error = x ; goto bad; } 546 547 /* 548 * Find the correct routing tree to use for this Address Family 549 */ 550 if ((rnh = rt_tables[dst->sa_family]) == 0) 551 senderr(EAFNOSUPPORT); 552 /* 553 * If we are adding a host route then we don't want to put 554 * a netmask in the tree, nor do we want to clone it. 555 */ 556 if (flags & RTF_HOST) { 557 netmask = 0; 558 flags &= ~(RTF_CLONING | RTF_PRCLONING); 559 } 560 switch (req) { 561 case RTM_DELETE: 562 /* 563 * Remove the item from the tree and return it. 564 * Complain if it is not there and do no more processing. 565 */ 566 if ((rn = rnh->rnh_deladdr(dst, netmask, rnh)) == 0) 567 senderr(ESRCH); 568 if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 569 panic ("rtrequest delete"); 570 rt = (struct rtentry *)rn; 571 572 /* 573 * Now search what's left of the subtree for any cloned 574 * routes which might have been formed from this node. 575 */ 576 if ((rt->rt_flags & (RTF_CLONING | RTF_PRCLONING)) && 577 rt_mask(rt)) { 578 rnh->rnh_walktree_from(rnh, dst, rt_mask(rt), 579 rt_fixdelete, rt); 580 } 581 582 /* 583 * Remove any external references we may have. 584 * This might result in another rtentry being freed if 585 * we held its last reference. 586 */ 587 if (rt->rt_gwroute) { 588 rt = rt->rt_gwroute; 589 RTFREE(rt); 590 (rt = (struct rtentry *)rn)->rt_gwroute = 0; 591 } 592 593 /* 594 * NB: RTF_UP must be set during the search above, 595 * because we might delete the last ref, causing 596 * rt to get freed prematurely. 597 * eh? then why not just add a reference? 598 * I'm not sure how RTF_UP helps matters. (JRE) 599 */ 600 rt->rt_flags &= ~RTF_UP; 601 602 /* 603 * give the protocol a chance to keep things in sync. 604 */ 605 if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest) 606 ifa->ifa_rtrequest(RTM_DELETE, rt, info); 607 608 /* 609 * one more rtentry floating around that is not 610 * linked to the routing table. 611 */ 612 rttrash++; 613 614 /* 615 * If the caller wants it, then it can have it, 616 * but it's up to it to free the rtentry as we won't be 617 * doing it. 618 */ 619 if (ret_nrt) 620 *ret_nrt = rt; 621 else if (rt->rt_refcnt <= 0) { 622 rt->rt_refcnt++; /* make a 1->0 transition */ 623 rtfree(rt); 624 } 625 break; 626 627 case RTM_RESOLVE: 628 if (ret_nrt == 0 || (rt = *ret_nrt) == 0) 629 senderr(EINVAL); 630 ifa = rt->rt_ifa; 631 flags = rt->rt_flags & 632 ~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC); 633 flags |= RTF_WASCLONED; 634 gateway = rt->rt_gateway; 635 if ((netmask = rt->rt_genmask) == 0) 636 flags |= RTF_HOST; 637 goto makeroute; 638 639 case RTM_ADD: 640 if ((flags & RTF_GATEWAY) && !gateway) 641 panic("rtrequest: GATEWAY but no gateway"); 642 643 if (info->rti_ifa == NULL && (error = rt_getifa(info))) 644 senderr(error); 645 ifa = info->rti_ifa; 646 647 makeroute: 648 R_Malloc(rt, struct rtentry *, sizeof(*rt)); 649 if (rt == 0) 650 senderr(ENOBUFS); 651 Bzero(rt, sizeof(*rt)); 652 rt->rt_flags = RTF_UP | flags; 653 /* 654 * Add the gateway. Possibly re-malloc-ing the storage for it 655 * also add the rt_gwroute if possible. 656 */ 657 if ((error = rt_setgate(rt, dst, gateway)) != 0) { 658 Free(rt); 659 senderr(error); 660 } 661 662 /* 663 * point to the (possibly newly malloc'd) dest address. 664 */ 665 ndst = rt_key(rt); 666 667 /* 668 * make sure it contains the value we want (masked if needed). 669 */ 670 if (netmask) { 671 rt_maskedcopy(dst, ndst, netmask); 672 } else 673 Bcopy(dst, ndst, dst->sa_len); 674 675 /* 676 * Note that we now have a reference to the ifa. 677 * This moved from below so that rnh->rnh_addaddr() can 678 * examine the ifa and ifa->ifa_ifp if it so desires. 679 */ 680 ifa->ifa_refcnt++; 681 rt->rt_ifa = ifa; 682 rt->rt_ifp = ifa->ifa_ifp; 683 /* XXX mtu manipulation will be done in rnh_addaddr -- itojun */ 684 685 rn = rnh->rnh_addaddr((caddr_t)ndst, (caddr_t)netmask, 686 rnh, rt->rt_nodes); 687 if (rn == 0) { 688 struct rtentry *rt2; 689 /* 690 * Uh-oh, we already have one of these in the tree. 691 * We do a special hack: if the route that's already 692 * there was generated by the protocol-cloning 693 * mechanism, then we just blow it away and retry 694 * the insertion of the new one. 695 */ 696 rt2 = rtalloc1(dst, 0, RTF_PRCLONING); 697 if (rt2 && rt2->rt_parent) { 698 rtrequest(RTM_DELETE, 699 (struct sockaddr *)rt_key(rt2), 700 rt2->rt_gateway, 701 rt_mask(rt2), rt2->rt_flags, 0); 702 RTFREE(rt2); 703 rn = rnh->rnh_addaddr((caddr_t)ndst, 704 (caddr_t)netmask, 705 rnh, rt->rt_nodes); 706 } else if (rt2) { 707 /* undo the extra ref we got */ 708 RTFREE(rt2); 709 } 710 } 711 712 /* 713 * If it still failed to go into the tree, 714 * then un-make it (this should be a function) 715 */ 716 if (rn == 0) { 717 if (rt->rt_gwroute) 718 rtfree(rt->rt_gwroute); 719 if (rt->rt_ifa) { 720 IFAFREE(rt->rt_ifa); 721 } 722 Free(rt_key(rt)); 723 Free(rt); 724 senderr(EEXIST); 725 } 726 727 rt->rt_parent = 0; 728 729 /* 730 * If we got here from RESOLVE, then we are cloning 731 * so clone the rest, and note that we 732 * are a clone (and increment the parent's references) 733 */ 734 if (req == RTM_RESOLVE) { 735 rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */ 736 rt->rt_rmx.rmx_pksent = 0; /* reset packet counter */ 737 if ((*ret_nrt)->rt_flags & (RTF_CLONING | RTF_PRCLONING)) { 738 rt->rt_parent = (*ret_nrt); 739 (*ret_nrt)->rt_refcnt++; 740 } 741 } 742 743 /* 744 * if this protocol has something to add to this then 745 * allow it to do that as well. 746 */ 747 if (ifa->ifa_rtrequest) 748 ifa->ifa_rtrequest(req, rt, info); 749 750 /* 751 * We repeat the same procedure from rt_setgate() here because 752 * it doesn't fire when we call it there because the node 753 * hasn't been added to the tree yet. 754 */ 755 if (req == RTM_ADD && 756 !(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) { 757 struct rtfc_arg arg; 758 arg.rnh = rnh; 759 arg.rt0 = rt; 760 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt), 761 rt_fixchange, &arg); 762 } 763 764 /* 765 * actually return a resultant rtentry and 766 * give the caller a single reference. 767 */ 768 if (ret_nrt) { 769 *ret_nrt = rt; 770 rt->rt_refcnt++; 771 } 772 break; 773 default: 774 error = EOPNOTSUPP; 775 } 776 bad: 777 splx(s); 778 return (error); 779 #undef dst 780 #undef gateway 781 #undef netmask 782 #undef ifaaddr 783 #undef ifpaddr 784 #undef flags 785 } 786 787 /* 788 * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family'' 789 * (i.e., the routes related to it by the operation of cloning). This 790 * routine is iterated over all potential former-child-routes by way of 791 * rnh->rnh_walktree_from() above, and those that actually are children of 792 * the late parent (passed in as VP here) are themselves deleted. 793 */ 794 static int 795 rt_fixdelete(rn, vp) 796 struct radix_node *rn; 797 void *vp; 798 { 799 struct rtentry *rt = (struct rtentry *)rn; 800 struct rtentry *rt0 = vp; 801 802 if (rt->rt_parent == rt0 && 803 !(rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) { 804 return rtrequest(RTM_DELETE, rt_key(rt), 805 (struct sockaddr *)0, rt_mask(rt), 806 rt->rt_flags, (struct rtentry **)0); 807 } 808 return 0; 809 } 810 811 /* 812 * This routine is called from rt_setgate() to do the analogous thing for 813 * adds and changes. There is the added complication in this case of a 814 * middle insert; i.e., insertion of a new network route between an older 815 * network route and (cloned) host routes. For this reason, a simple check 816 * of rt->rt_parent is insufficient; each candidate route must be tested 817 * against the (mask, value) of the new route (passed as before in vp) 818 * to see if the new route matches it. 819 * 820 * XXX - it may be possible to do fixdelete() for changes and reserve this 821 * routine just for adds. I'm not sure why I thought it was necessary to do 822 * changes this way. 823 */ 824 #ifdef DEBUG 825 static int rtfcdebug = 0; 826 #endif 827 828 static int 829 rt_fixchange(rn, vp) 830 struct radix_node *rn; 831 void *vp; 832 { 833 struct rtentry *rt = (struct rtentry *)rn; 834 struct rtfc_arg *ap = vp; 835 struct rtentry *rt0 = ap->rt0; 836 struct radix_node_head *rnh = ap->rnh; 837 u_char *xk1, *xm1, *xk2, *xmp; 838 int i, len, mlen; 839 840 #ifdef DEBUG 841 if (rtfcdebug) 842 printf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0); 843 #endif 844 845 if (!rt->rt_parent || 846 (rt->rt_flags & (RTF_PINNED | RTF_CLONING | RTF_PRCLONING))) { 847 #ifdef DEBUG 848 if(rtfcdebug) printf("no parent, pinned or cloning\n"); 849 #endif 850 return 0; 851 } 852 853 if (rt->rt_parent == rt0) { 854 #ifdef DEBUG 855 if(rtfcdebug) printf("parent match\n"); 856 #endif 857 return rtrequest(RTM_DELETE, rt_key(rt), 858 (struct sockaddr *)0, rt_mask(rt), 859 rt->rt_flags, (struct rtentry **)0); 860 } 861 862 /* 863 * There probably is a function somewhere which does this... 864 * if not, there should be. 865 */ 866 len = imin(((struct sockaddr *)rt_key(rt0))->sa_len, 867 ((struct sockaddr *)rt_key(rt))->sa_len); 868 869 xk1 = (u_char *)rt_key(rt0); 870 xm1 = (u_char *)rt_mask(rt0); 871 xk2 = (u_char *)rt_key(rt); 872 873 /* avoid applying a less specific route */ 874 xmp = (u_char *)rt_mask(rt->rt_parent); 875 mlen = ((struct sockaddr *)rt_key(rt->rt_parent))->sa_len; 876 if (mlen > ((struct sockaddr *)rt_key(rt0))->sa_len) { 877 #ifdef DEBUG 878 if (rtfcdebug) 879 printf("rt_fixchange: inserting a less " 880 "specific route\n"); 881 #endif 882 return 0; 883 } 884 for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) { 885 if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) { 886 #ifdef DEBUG 887 if (rtfcdebug) 888 printf("rt_fixchange: inserting a less " 889 "specific route\n"); 890 #endif 891 return 0; 892 } 893 } 894 895 for (i = rnh->rnh_treetop->rn_offset; i < len; i++) { 896 if ((xk2[i] & xm1[i]) != xk1[i]) { 897 #ifdef DEBUG 898 if(rtfcdebug) printf("no match\n"); 899 #endif 900 return 0; 901 } 902 } 903 904 /* 905 * OK, this node is a clone, and matches the node currently being 906 * changed/added under the node's mask. So, get rid of it. 907 */ 908 #ifdef DEBUG 909 if(rtfcdebug) printf("deleting\n"); 910 #endif 911 return rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0, 912 rt_mask(rt), rt->rt_flags, (struct rtentry **)0); 913 } 914 915 #define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 916 917 int 918 rt_setgate(rt0, dst, gate) 919 struct rtentry *rt0; 920 struct sockaddr *dst, *gate; 921 { 922 caddr_t new, old; 923 int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len); 924 struct rtentry *rt = rt0; 925 struct radix_node_head *rnh = rt_tables[dst->sa_family]; 926 927 /* 928 * A host route with the destination equal to the gateway 929 * will interfere with keeping LLINFO in the routing 930 * table, so disallow it. 931 */ 932 if (((rt0->rt_flags & (RTF_HOST|RTF_GATEWAY|RTF_LLINFO)) == 933 (RTF_HOST|RTF_GATEWAY)) && 934 (dst->sa_len == gate->sa_len) && 935 (bcmp(dst, gate, dst->sa_len) == 0)) { 936 /* 937 * The route might already exist if this is an RTM_CHANGE 938 * or a routing redirect, so try to delete it. 939 */ 940 if (rt_key(rt0)) 941 rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt0), 942 rt0->rt_gateway, rt_mask(rt0), rt0->rt_flags, 0); 943 return EADDRNOTAVAIL; 944 } 945 946 /* 947 * Both dst and gateway are stored in the same malloc'd chunk 948 * (If I ever get my hands on....) 949 * if we need to malloc a new chunk, then keep the old one around 950 * till we don't need it any more. 951 */ 952 if (rt->rt_gateway == 0 || glen > ROUNDUP(rt->rt_gateway->sa_len)) { 953 old = (caddr_t)rt_key(rt); 954 R_Malloc(new, caddr_t, dlen + glen); 955 if (new == 0) 956 return ENOBUFS; 957 rt->rt_nodes->rn_key = new; 958 } else { 959 /* 960 * otherwise just overwrite the old one 961 */ 962 new = rt->rt_nodes->rn_key; 963 old = 0; 964 } 965 966 /* 967 * copy the new gateway value into the memory chunk 968 */ 969 Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen); 970 971 /* 972 * if we are replacing the chunk (or it's new) we need to 973 * replace the dst as well 974 */ 975 if (old) { 976 Bcopy(dst, new, dlen); 977 Free(old); 978 } 979 980 /* 981 * If there is already a gwroute, it's now almost definitly wrong 982 * so drop it. 983 */ 984 if (rt->rt_gwroute != NULL) { 985 RTFREE(rt->rt_gwroute); 986 rt->rt_gwroute = NULL; 987 } 988 /* 989 * Cloning loop avoidance: 990 * In the presence of protocol-cloning and bad configuration, 991 * it is possible to get stuck in bottomless mutual recursion 992 * (rtrequest rt_setgate rtalloc1). We avoid this by not allowing 993 * protocol-cloning to operate for gateways (which is probably the 994 * correct choice anyway), and avoid the resulting reference loops 995 * by disallowing any route to run through itself as a gateway. 996 * This is obviously mandatory when we get rt->rt_output(). 997 */ 998 if (rt->rt_flags & RTF_GATEWAY) { 999 rt->rt_gwroute = rtalloc1(gate, 1, RTF_PRCLONING); 1000 if (rt->rt_gwroute == rt) { 1001 RTFREE(rt->rt_gwroute); 1002 rt->rt_gwroute = 0; 1003 return EDQUOT; /* failure */ 1004 } 1005 } 1006 1007 /* 1008 * This isn't going to do anything useful for host routes, so 1009 * don't bother. Also make sure we have a reasonable mask 1010 * (we don't yet have one during adds). 1011 */ 1012 if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) { 1013 struct rtfc_arg arg; 1014 arg.rnh = rnh; 1015 arg.rt0 = rt; 1016 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt), 1017 rt_fixchange, &arg); 1018 } 1019 1020 return 0; 1021 } 1022 1023 static void 1024 rt_maskedcopy(src, dst, netmask) 1025 struct sockaddr *src, *dst, *netmask; 1026 { 1027 u_char *cp1 = (u_char *)src; 1028 u_char *cp2 = (u_char *)dst; 1029 u_char *cp3 = (u_char *)netmask; 1030 u_char *cplim = cp2 + *cp3; 1031 u_char *cplim2 = cp2 + *cp1; 1032 1033 *cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */ 1034 cp3 += 2; 1035 if (cplim > cplim2) 1036 cplim = cplim2; 1037 while (cp2 < cplim) 1038 *cp2++ = *cp1++ & *cp3++; 1039 if (cp2 < cplim2) 1040 bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2)); 1041 } 1042 1043 /* 1044 * Set up a routing table entry, normally 1045 * for an interface. 1046 */ 1047 int 1048 rtinit(ifa, cmd, flags) 1049 struct ifaddr *ifa; 1050 int cmd, flags; 1051 { 1052 struct rtentry *rt; 1053 struct sockaddr *dst; 1054 struct sockaddr *deldst; 1055 struct sockaddr *netmask; 1056 struct mbuf *m = 0; 1057 struct rtentry *nrt = 0; 1058 struct radix_node_head *rnh; 1059 struct radix_node *rn; 1060 int error; 1061 struct rt_addrinfo info; 1062 1063 if (flags & RTF_HOST) { 1064 dst = ifa->ifa_dstaddr; 1065 netmask = NULL; 1066 } else { 1067 dst = ifa->ifa_addr; 1068 netmask = ifa->ifa_netmask; 1069 } 1070 /* 1071 * If it's a delete, check that if it exists, it's on the correct 1072 * interface or we might scrub a route to another ifa which would 1073 * be confusing at best and possibly worse. 1074 */ 1075 if (cmd == RTM_DELETE) { 1076 /* 1077 * It's a delete, so it should already exist.. 1078 * If it's a net, mask off the host bits 1079 * (Assuming we have a mask) 1080 */ 1081 if (netmask != NULL) { 1082 m = m_get(M_DONTWAIT, MT_SONAME); 1083 if (m == NULL) 1084 return(ENOBUFS); 1085 deldst = mtod(m, struct sockaddr *); 1086 rt_maskedcopy(dst, deldst, netmask); 1087 dst = deldst; 1088 } 1089 /* 1090 * Look up an rtentry that is in the routing tree and 1091 * contains the correct info. 1092 */ 1093 if ((rnh = rt_tables[dst->sa_family]) == NULL || 1094 (rn = rnh->rnh_lookup(dst, netmask, rnh)) == NULL || 1095 (rn->rn_flags & RNF_ROOT) || 1096 ((struct rtentry *)rn)->rt_ifa != ifa || 1097 !equal(SA(rn->rn_key), dst)) { 1098 if (m) 1099 (void) m_free(m); 1100 return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 1101 } 1102 /* XXX */ 1103 #if 0 1104 else { 1105 /* 1106 * One would think that as we are deleting, and we know 1107 * it doesn't exist, we could just return at this point 1108 * with an "ELSE" clause, but apparently not.. 1109 */ 1110 return (flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 1111 } 1112 #endif 1113 } 1114 /* 1115 * Do the actual request 1116 */ 1117 bzero((caddr_t)&info, sizeof(info)); 1118 info.rti_ifa = ifa; 1119 info.rti_flags = flags | ifa->ifa_flags; 1120 info.rti_info[RTAX_DST] = dst; 1121 info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr; 1122 info.rti_info[RTAX_NETMASK] = netmask; 1123 error = rtrequest1(cmd, &info, &nrt); 1124 if (error == 0 && (rt = nrt) != NULL) { 1125 /* 1126 * notify any listening routing agents of the change 1127 */ 1128 rt_newaddrmsg(cmd, ifa, error, rt); 1129 if (cmd == RTM_DELETE) { 1130 /* 1131 * If we are deleting, and we found an entry, then 1132 * it's been removed from the tree.. now throw it away. 1133 */ 1134 if (rt->rt_refcnt <= 0) { 1135 rt->rt_refcnt++; /* make a 1->0 transition */ 1136 rtfree(rt); 1137 } 1138 } else if (cmd == RTM_ADD) { 1139 /* 1140 * We just wanted to add it.. we don't actually 1141 * need a reference. 1142 */ 1143 rt->rt_refcnt--; 1144 } 1145 } 1146 if (m) 1147 (void) m_free(m); 1148 return (error); 1149 } 1150 1151 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */ 1152 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0); 1153