Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/net/route.c
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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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS 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 * @(#)route.c 8.3.1.1 (Berkeley) 2/23/95 30 * $FreeBSD$ 31 */ 32 /************************************************************************ 33 * Note: In this file a 'fib' is a "forwarding information base" * 34 * Which is the new name for an in kernel routing (next hop) table. * 35 ***********************************************************************/ 36 37 #include "opt_inet.h" 38 #include "opt_route.h" 39 #include "opt_mrouting.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/socket.h> 46 #include <sys/sysctl.h> 47 #include <sys/sysproto.h> 48 #include <sys/proc.h> 49 #include <sys/domain.h> 50 #include <sys/kernel.h> 51 52 #include <net/if.h> 53 #include <net/route.h> 54 55 #include <netinet/in.h> 56 #include <netinet/ip_mroute.h> 57 58 #include <vm/uma.h> 59 60 #ifndef ROUTETABLES 61 #define RT_NUMFIBS 1 62 #define RT_MAXFIBS 1 63 #else 64 /* while we use 4 bits in the mbuf flags, 65 * we are limited to 16 66 */ 67 #define RT_MAXFIBS 16 68 #if ROUTETABLES > RT_MAXFIBS 69 #define RT_NUMFIBS RT_MAXFIBS 70 #error "ROUTETABLES defined too big" 71 #else 72 #if ROUTETABLES == 0 73 #define RT_NUMFIBS 1 74 #else 75 #define RT_NUMFIBS ROUTETABLES 76 #endif 77 #endif 78 #endif 79 80 u_int rt_numfibs = RT_NUMFIBS; 81 SYSCTL_INT(_net, OID_AUTO, fibs, CTLFLAG_RD, &rt_numfibs, 0, ""); 82 /* 83 * Allow the boot code to allow LESS than RT_MAXFIBS to be used. 84 * We can't do more because storage is statically allocated for now. 85 */ 86 TUNABLE_INT("net.fibs", &rt_numfibs); 87 88 /* 89 * By default add routes to all fibs for new interfaces. 90 * Once this is set to 0 then only allocate routes on interface 91 * changes for the FIB of the caller when adding a new set of addresses 92 * to an interface. XXX this is a shotgun aproach to a problem that needs 93 * a more fine grained solution.. that will come. 94 */ 95 u_int rt_add_addr_allfibs = 1; 96 SYSCTL_INT(_net, OID_AUTO, add_addr_allfibs, CTLFLAG_RW, 97 &rt_add_addr_allfibs, 0, ""); 98 TUNABLE_INT("net.add_addr_allfibs", &rt_add_addr_allfibs); 99 100 static struct rtstat rtstat; 101 102 /* by default only the first 'row' of tables will be accessed. */ 103 /* 104 * XXXMRT When we fix netstat, and do this differnetly, 105 * we can allocate this dynamically. As long as we are keeping 106 * things backwards compaitble we need to allocate this 107 * statically. 108 */ 109 struct radix_node_head *rt_tables[RT_MAXFIBS][AF_MAX+1]; 110 111 static int rttrash; /* routes not in table but not freed */ 112 113 static void rt_maskedcopy(struct sockaddr *, 114 struct sockaddr *, struct sockaddr *); 115 116 /* compare two sockaddr structures */ 117 #define sa_equal(a1, a2) (bcmp((a1), (a2), (a1)->sa_len) == 0) 118 119 /* 120 * Convert a 'struct radix_node *' to a 'struct rtentry *'. 121 * The operation can be done safely (in this code) because a 122 * 'struct rtentry' starts with two 'struct radix_node''s, the first 123 * one representing leaf nodes in the routing tree, which is 124 * what the code in radix.c passes us as a 'struct radix_node'. 125 * 126 * But because there are a lot of assumptions in this conversion, 127 * do not cast explicitly, but always use the macro below. 128 */ 129 #define RNTORT(p) ((struct rtentry *)(p)) 130 131 static uma_zone_t rtzone; /* Routing table UMA zone. */ 132 133 /* 134 * handler for net.my_fibnum 135 */ 136 static int 137 sysctl_my_fibnum(SYSCTL_HANDLER_ARGS) 138 { 139 int fibnum; 140 int error; 141 142 fibnum = curthread->td_proc->p_fibnum; 143 error = sysctl_handle_int(oidp, &fibnum, 0, req); 144 return (error); 145 } 146 147 SYSCTL_PROC(_net, OID_AUTO, my_fibnum, CTLTYPE_INT|CTLFLAG_RD, 148 NULL, 0, &sysctl_my_fibnum, "I", "default FIB of caller"); 149 150 static void 151 route_init(void) 152 { 153 int table; 154 struct domain *dom; 155 int fam; 156 157 /* whack teh tunable ints into line. */ 158 if (rt_numfibs > RT_MAXFIBS) 159 rt_numfibs = RT_MAXFIBS; 160 if (rt_numfibs == 0) 161 rt_numfibs = 1; 162 rtzone = uma_zcreate("rtentry", sizeof(struct rtentry), NULL, NULL, 163 NULL, NULL, UMA_ALIGN_PTR, 0); 164 rn_init(); /* initialize all zeroes, all ones, mask table */ 165 166 for (dom = domains; dom; dom = dom->dom_next) { 167 if (dom->dom_rtattach) { 168 for (table = 0; table < rt_numfibs; table++) { 169 if ( (fam = dom->dom_family) == AF_INET || 170 table == 0) { 171 /* for now only AF_INET has > 1 table */ 172 /* XXX MRT 173 * rtattach will be also called 174 * from vfs_export.c but the 175 * offset will be 0 176 * (only for AF_INET and AF_INET6 177 * which don't need it anyhow) 178 */ 179 dom->dom_rtattach( 180 (void **)&rt_tables[table][fam], 181 dom->dom_rtoffset); 182 } else { 183 break; 184 } 185 } 186 } 187 } 188 } 189 190 #ifndef _SYS_SYSPROTO_H_ 191 struct setfib_args { 192 int fibnum; 193 }; 194 #endif 195 int 196 setfib(struct thread *td, struct setfib_args *uap) 197 { 198 if (uap->fibnum < 0 || uap->fibnum >= rt_numfibs) 199 return EINVAL; 200 td->td_proc->p_fibnum = uap->fibnum; 201 return (0); 202 } 203 204 /* 205 * Packet routing routines. 206 */ 207 void 208 rtalloc(struct route *ro) 209 { 210 rtalloc_ign_fib(ro, 0UL, 0); 211 } 212 213 void 214 rtalloc_fib(struct route *ro, u_int fibnum) 215 { 216 rtalloc_ign_fib(ro, 0UL, fibnum); 217 } 218 219 void 220 rtalloc_ign(struct route *ro, u_long ignore) 221 { 222 struct rtentry *rt; 223 224 if ((rt = ro->ro_rt) != NULL) { 225 if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP) 226 return; 227 RTFREE(rt); 228 ro->ro_rt = NULL; 229 } 230 ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, ignore, 0); 231 if (ro->ro_rt) 232 RT_UNLOCK(ro->ro_rt); 233 } 234 235 void 236 rtalloc_ign_fib(struct route *ro, u_long ignore, u_int fibnum) 237 { 238 struct rtentry *rt; 239 240 if ((rt = ro->ro_rt) != NULL) { 241 if (rt->rt_ifp != NULL && rt->rt_flags & RTF_UP) 242 return; 243 RTFREE(rt); 244 ro->ro_rt = NULL; 245 } 246 ro->ro_rt = rtalloc1_fib(&ro->ro_dst, 1, ignore, fibnum); 247 if (ro->ro_rt) 248 RT_UNLOCK(ro->ro_rt); 249 } 250 251 /* 252 * Look up the route that matches the address given 253 * Or, at least try.. Create a cloned route if needed. 254 * 255 * The returned route, if any, is locked. 256 */ 257 struct rtentry * 258 rtalloc1(struct sockaddr *dst, int report, u_long ignflags) 259 { 260 return (rtalloc1_fib(dst, report, ignflags, 0)); 261 } 262 263 struct rtentry * 264 rtalloc1_fib(struct sockaddr *dst, int report, u_long ignflags, 265 u_int fibnum) 266 { 267 struct radix_node_head *rnh; 268 struct rtentry *rt; 269 struct radix_node *rn; 270 struct rtentry *newrt; 271 struct rt_addrinfo info; 272 u_long nflags; 273 int err = 0, msgtype = RTM_MISS; 274 int needlock; 275 276 KASSERT((fibnum < rt_numfibs), ("rtalloc1_fib: bad fibnum")); 277 if (dst->sa_family != AF_INET) /* Only INET supports > 1 fib now */ 278 fibnum = 0; 279 rnh = rt_tables[fibnum][dst->sa_family]; 280 newrt = NULL; 281 /* 282 * Look up the address in the table for that Address Family 283 */ 284 if (rnh == NULL) { 285 rtstat.rts_unreach++; 286 goto miss2; 287 } 288 needlock = !(ignflags & RTF_RNH_LOCKED); 289 if (needlock) 290 RADIX_NODE_HEAD_LOCK(rnh); 291 #ifdef INVARIANTS 292 else 293 RADIX_NODE_HEAD_LOCK_ASSERT(rnh); 294 #endif 295 if ((rn = rnh->rnh_matchaddr(dst, rnh)) && 296 (rn->rn_flags & RNF_ROOT) == 0) { 297 /* 298 * If we find it and it's not the root node, then 299 * get a reference on the rtentry associated. 300 */ 301 newrt = rt = RNTORT(rn); 302 nflags = rt->rt_flags & ~ignflags; 303 if (report && (nflags & RTF_CLONING)) { 304 /* 305 * We are apparently adding (report = 0 in delete). 306 * If it requires that it be cloned, do so. 307 * (This implies it wasn't a HOST route.) 308 */ 309 err = rtrequest_fib(RTM_RESOLVE, dst, NULL, 310 NULL, 0, &newrt, fibnum); 311 if (err) { 312 /* 313 * If the cloning didn't succeed, maybe 314 * what we have will do. Return that. 315 */ 316 newrt = rt; /* existing route */ 317 RT_LOCK(newrt); 318 RT_ADDREF(newrt); 319 goto miss; 320 } 321 KASSERT(newrt, ("no route and no error")); 322 RT_LOCK(newrt); 323 if (newrt->rt_flags & RTF_XRESOLVE) { 324 /* 325 * If the new route specifies it be 326 * externally resolved, then go do that. 327 */ 328 msgtype = RTM_RESOLVE; 329 goto miss; 330 } 331 /* Inform listeners of the new route. */ 332 bzero(&info, sizeof(info)); 333 info.rti_info[RTAX_DST] = rt_key(newrt); 334 info.rti_info[RTAX_NETMASK] = rt_mask(newrt); 335 info.rti_info[RTAX_GATEWAY] = newrt->rt_gateway; 336 if (newrt->rt_ifp != NULL) { 337 info.rti_info[RTAX_IFP] = 338 newrt->rt_ifp->if_addr->ifa_addr; 339 info.rti_info[RTAX_IFA] = newrt->rt_ifa->ifa_addr; 340 } 341 rt_missmsg_fib(RTM_ADD, &info, newrt->rt_flags, 0, 342 fibnum); 343 } else { 344 KASSERT(rt == newrt, ("locking wrong route")); 345 RT_LOCK(newrt); 346 RT_ADDREF(newrt); 347 } 348 if (needlock) 349 RADIX_NODE_HEAD_UNLOCK(rnh); 350 } else { 351 /* 352 * Either we hit the root or couldn't find any match, 353 * Which basically means 354 * "caint get there frm here" 355 */ 356 rtstat.rts_unreach++; 357 miss: 358 if (needlock) 359 RADIX_NODE_HEAD_UNLOCK(rnh); 360 miss2: if (report) { 361 /* 362 * If required, report the failure to the supervising 363 * Authorities. 364 * For a delete, this is not an error. (report == 0) 365 */ 366 bzero(&info, sizeof(info)); 367 info.rti_info[RTAX_DST] = dst; 368 rt_missmsg_fib(msgtype, &info, 0, err, fibnum); 369 } 370 } 371 if (newrt) 372 RT_LOCK_ASSERT(newrt); 373 return (newrt); 374 } 375 376 /* 377 * Remove a reference count from an rtentry. 378 * If the count gets low enough, take it out of the routing table 379 */ 380 void 381 rtfree(struct rtentry *rt) 382 { 383 struct radix_node_head *rnh; 384 385 KASSERT(rt != NULL,("%s: NULL rt", __func__)); 386 rnh = rt_tables[rt->rt_fibnum][rt_key(rt)->sa_family]; 387 KASSERT(rnh != NULL,("%s: NULL rnh", __func__)); 388 389 RT_LOCK_ASSERT(rt); 390 391 /* 392 * The callers should use RTFREE_LOCKED() or RTFREE(), so 393 * we should come here exactly with the last reference. 394 */ 395 RT_REMREF(rt); 396 if (rt->rt_refcnt > 0) { 397 printf("%s: %p has %lu refs\n", __func__, rt, rt->rt_refcnt); 398 goto done; 399 } 400 401 /* 402 * On last reference give the "close method" a chance 403 * to cleanup private state. This also permits (for 404 * IPv4 and IPv6) a chance to decide if the routing table 405 * entry should be purged immediately or at a later time. 406 * When an immediate purge is to happen the close routine 407 * typically calls rtexpunge which clears the RTF_UP flag 408 * on the entry so that the code below reclaims the storage. 409 */ 410 if (rt->rt_refcnt == 0 && rnh->rnh_close) 411 rnh->rnh_close((struct radix_node *)rt, rnh); 412 413 /* 414 * If we are no longer "up" (and ref == 0) 415 * then we can free the resources associated 416 * with the route. 417 */ 418 if ((rt->rt_flags & RTF_UP) == 0) { 419 if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 420 panic("rtfree 2"); 421 /* 422 * the rtentry must have been removed from the routing table 423 * so it is represented in rttrash.. remove that now. 424 */ 425 rttrash--; 426 #ifdef DIAGNOSTIC 427 if (rt->rt_refcnt < 0) { 428 printf("rtfree: %p not freed (neg refs)\n", rt); 429 goto done; 430 } 431 #endif 432 /* 433 * release references on items we hold them on.. 434 * e.g other routes and ifaddrs. 435 */ 436 if (rt->rt_ifa) 437 IFAFREE(rt->rt_ifa); 438 rt->rt_parent = NULL; /* NB: no refcnt on parent */ 439 440 /* 441 * The key is separatly alloc'd so free it (see rt_setgate()). 442 * This also frees the gateway, as they are always malloc'd 443 * together. 444 */ 445 Free(rt_key(rt)); 446 447 /* 448 * and the rtentry itself of course 449 */ 450 RT_LOCK_DESTROY(rt); 451 uma_zfree(rtzone, rt); 452 return; 453 } 454 done: 455 RT_UNLOCK(rt); 456 } 457 458 459 /* 460 * Force a routing table entry to the specified 461 * destination to go through the given gateway. 462 * Normally called as a result of a routing redirect 463 * message from the network layer. 464 */ 465 void 466 rtredirect(struct sockaddr *dst, 467 struct sockaddr *gateway, 468 struct sockaddr *netmask, 469 int flags, 470 struct sockaddr *src) 471 { 472 473 rtredirect_fib(dst, gateway, netmask, flags, src, 0); 474 } 475 476 void 477 rtredirect_fib(struct sockaddr *dst, 478 struct sockaddr *gateway, 479 struct sockaddr *netmask, 480 int flags, 481 struct sockaddr *src, 482 u_int fibnum) 483 { 484 struct rtentry *rt, *rt0 = NULL; 485 int error = 0; 486 short *stat = NULL; 487 struct rt_addrinfo info; 488 struct ifaddr *ifa; 489 struct radix_node_head *rnh = 490 rt_tables[fibnum][dst->sa_family]; 491 492 /* verify the gateway is directly reachable */ 493 if ((ifa = ifa_ifwithnet(gateway)) == NULL) { 494 error = ENETUNREACH; 495 goto out; 496 } 497 rt = rtalloc1_fib(dst, 0, 0UL, fibnum); /* NB: rt is locked */ 498 /* 499 * If the redirect isn't from our current router for this dst, 500 * it's either old or wrong. If it redirects us to ourselves, 501 * we have a routing loop, perhaps as a result of an interface 502 * going down recently. 503 */ 504 if (!(flags & RTF_DONE) && rt && 505 (!sa_equal(src, rt->rt_gateway) || rt->rt_ifa != ifa)) 506 error = EINVAL; 507 else if (ifa_ifwithaddr(gateway)) 508 error = EHOSTUNREACH; 509 if (error) 510 goto done; 511 /* 512 * Create a new entry if we just got back a wildcard entry 513 * or the lookup failed. This is necessary for hosts 514 * which use routing redirects generated by smart gateways 515 * to dynamically build the routing tables. 516 */ 517 if (rt == NULL || (rt_mask(rt) && rt_mask(rt)->sa_len < 2)) 518 goto create; 519 /* 520 * Don't listen to the redirect if it's 521 * for a route to an interface. 522 */ 523 if (rt->rt_flags & RTF_GATEWAY) { 524 if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) { 525 /* 526 * Changing from route to net => route to host. 527 * Create new route, rather than smashing route to net. 528 */ 529 create: 530 rt0 = rt; 531 rt = NULL; 532 533 flags |= RTF_GATEWAY | RTF_DYNAMIC; 534 bzero((caddr_t)&info, sizeof(info)); 535 info.rti_info[RTAX_DST] = dst; 536 info.rti_info[RTAX_GATEWAY] = gateway; 537 info.rti_info[RTAX_NETMASK] = netmask; 538 info.rti_ifa = ifa; 539 info.rti_flags = flags; 540 if (rt0 != NULL) 541 RT_UNLOCK(rt0); /* drop lock to avoid LOR with RNH */ 542 error = rtrequest1_fib(RTM_ADD, &info, &rt, fibnum); 543 if (rt != NULL) { 544 RT_LOCK(rt); 545 EVENTHANDLER_INVOKE(route_redirect_event, rt0, rt, dst); 546 flags = rt->rt_flags; 547 } 548 if (rt0) 549 RTFREE(rt0); 550 551 stat = &rtstat.rts_dynamic; 552 } else { 553 struct rtentry *gwrt; 554 555 /* 556 * Smash the current notion of the gateway to 557 * this destination. Should check about netmask!!! 558 */ 559 rt->rt_flags |= RTF_MODIFIED; 560 flags |= RTF_MODIFIED; 561 stat = &rtstat.rts_newgateway; 562 /* 563 * add the key and gateway (in one malloc'd chunk). 564 */ 565 RT_UNLOCK(rt); 566 RADIX_NODE_HEAD_LOCK(rnh); 567 RT_LOCK(rt); 568 rt_setgate(rt, rt_key(rt), gateway); 569 gwrt = rtalloc1(gateway, 1, RTF_RNH_LOCKED); 570 RADIX_NODE_HEAD_UNLOCK(rnh); 571 EVENTHANDLER_INVOKE(route_redirect_event, rt, gwrt, dst); 572 RTFREE_LOCKED(gwrt); 573 } 574 } else 575 error = EHOSTUNREACH; 576 done: 577 if (rt) 578 RTFREE_LOCKED(rt); 579 out: 580 if (error) 581 rtstat.rts_badredirect++; 582 else if (stat != NULL) 583 (*stat)++; 584 bzero((caddr_t)&info, sizeof(info)); 585 info.rti_info[RTAX_DST] = dst; 586 info.rti_info[RTAX_GATEWAY] = gateway; 587 info.rti_info[RTAX_NETMASK] = netmask; 588 info.rti_info[RTAX_AUTHOR] = src; 589 rt_missmsg_fib(RTM_REDIRECT, &info, flags, error, fibnum); 590 } 591 592 int 593 rtioctl(u_long req, caddr_t data) 594 { 595 return (rtioctl_fib(req, data, 0)); 596 } 597 598 /* 599 * Routing table ioctl interface. 600 */ 601 int 602 rtioctl_fib(u_long req, caddr_t data, u_int fibnum) 603 { 604 605 /* 606 * If more ioctl commands are added here, make sure the proper 607 * super-user checks are being performed because it is possible for 608 * prison-root to make it this far if raw sockets have been enabled 609 * in jails. 610 */ 611 #ifdef INET 612 /* Multicast goop, grrr... */ 613 return mrt_ioctl ? mrt_ioctl(req, data, fibnum) : EOPNOTSUPP; 614 #else /* INET */ 615 return ENXIO; 616 #endif /* INET */ 617 } 618 619 struct ifaddr * 620 ifa_ifwithroute(int flags, struct sockaddr *dst, struct sockaddr *gateway) 621 { 622 return (ifa_ifwithroute_fib(flags, dst, gateway, 0)); 623 } 624 625 struct ifaddr * 626 ifa_ifwithroute_fib(int flags, struct sockaddr *dst, struct sockaddr *gateway, 627 u_int fibnum) 628 { 629 register struct ifaddr *ifa; 630 int not_found = 0; 631 632 if ((flags & RTF_GATEWAY) == 0) { 633 /* 634 * If we are adding a route to an interface, 635 * and the interface is a pt to pt link 636 * we should search for the destination 637 * as our clue to the interface. Otherwise 638 * we can use the local address. 639 */ 640 ifa = NULL; 641 if (flags & RTF_HOST) 642 ifa = ifa_ifwithdstaddr(dst); 643 if (ifa == NULL) 644 ifa = ifa_ifwithaddr(gateway); 645 } else { 646 /* 647 * If we are adding a route to a remote net 648 * or host, the gateway may still be on the 649 * other end of a pt to pt link. 650 */ 651 ifa = ifa_ifwithdstaddr(gateway); 652 } 653 if (ifa == NULL) 654 ifa = ifa_ifwithnet(gateway); 655 if (ifa == NULL) { 656 struct rtentry *rt = rtalloc1_fib(gateway, 0, RTF_RNH_LOCKED, fibnum); 657 if (rt == NULL) 658 return (NULL); 659 /* 660 * dismiss a gateway that is reachable only 661 * through the default router 662 */ 663 switch (gateway->sa_family) { 664 case AF_INET: 665 if (satosin(rt_key(rt))->sin_addr.s_addr == INADDR_ANY) 666 not_found = 1; 667 break; 668 case AF_INET6: 669 if (IN6_IS_ADDR_UNSPECIFIED(&satosin6(rt_key(rt))->sin6_addr)) 670 not_found = 1; 671 break; 672 default: 673 break; 674 } 675 RT_REMREF(rt); 676 RT_UNLOCK(rt); 677 if (not_found) 678 return (NULL); 679 if ((ifa = rt->rt_ifa) == NULL) 680 return (NULL); 681 } 682 if (ifa->ifa_addr->sa_family != dst->sa_family) { 683 struct ifaddr *oifa = ifa; 684 ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp); 685 if (ifa == NULL) 686 ifa = oifa; 687 } 688 return (ifa); 689 } 690 691 static walktree_f_t rt_fixdelete; 692 static walktree_f_t rt_fixchange; 693 694 struct rtfc_arg { 695 struct rtentry *rt0; 696 struct radix_node_head *rnh; 697 }; 698 699 /* 700 * Do appropriate manipulations of a routing tree given 701 * all the bits of info needed 702 */ 703 int 704 rtrequest(int req, 705 struct sockaddr *dst, 706 struct sockaddr *gateway, 707 struct sockaddr *netmask, 708 int flags, 709 struct rtentry **ret_nrt) 710 { 711 return (rtrequest_fib(req, dst, gateway, netmask, flags, ret_nrt, 0)); 712 } 713 714 int 715 rtrequest_fib(int req, 716 struct sockaddr *dst, 717 struct sockaddr *gateway, 718 struct sockaddr *netmask, 719 int flags, 720 struct rtentry **ret_nrt, 721 u_int fibnum) 722 { 723 struct rt_addrinfo info; 724 725 if (dst->sa_len == 0) 726 return(EINVAL); 727 728 bzero((caddr_t)&info, sizeof(info)); 729 info.rti_flags = flags; 730 info.rti_info[RTAX_DST] = dst; 731 info.rti_info[RTAX_GATEWAY] = gateway; 732 info.rti_info[RTAX_NETMASK] = netmask; 733 return rtrequest1_fib(req, &info, ret_nrt, fibnum); 734 } 735 736 /* 737 * These (questionable) definitions of apparent local variables apply 738 * to the next two functions. XXXXXX!!! 739 */ 740 #define dst info->rti_info[RTAX_DST] 741 #define gateway info->rti_info[RTAX_GATEWAY] 742 #define netmask info->rti_info[RTAX_NETMASK] 743 #define ifaaddr info->rti_info[RTAX_IFA] 744 #define ifpaddr info->rti_info[RTAX_IFP] 745 #define flags info->rti_flags 746 747 int 748 rt_getifa(struct rt_addrinfo *info) 749 { 750 return (rt_getifa_fib(info, 0)); 751 } 752 753 int 754 rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum) 755 { 756 struct ifaddr *ifa; 757 int error = 0; 758 759 /* 760 * ifp may be specified by sockaddr_dl 761 * when protocol address is ambiguous. 762 */ 763 if (info->rti_ifp == NULL && ifpaddr != NULL && 764 ifpaddr->sa_family == AF_LINK && 765 (ifa = ifa_ifwithnet(ifpaddr)) != NULL) 766 info->rti_ifp = ifa->ifa_ifp; 767 if (info->rti_ifa == NULL && ifaaddr != NULL) 768 info->rti_ifa = ifa_ifwithaddr(ifaaddr); 769 if (info->rti_ifa == NULL) { 770 struct sockaddr *sa; 771 772 sa = ifaaddr != NULL ? ifaaddr : 773 (gateway != NULL ? gateway : dst); 774 if (sa != NULL && info->rti_ifp != NULL) 775 info->rti_ifa = ifaof_ifpforaddr(sa, info->rti_ifp); 776 else if (dst != NULL && gateway != NULL) 777 info->rti_ifa = ifa_ifwithroute_fib(flags, dst, gateway, 778 fibnum); 779 else if (sa != NULL) 780 info->rti_ifa = ifa_ifwithroute_fib(flags, sa, sa, 781 fibnum); 782 } 783 if ((ifa = info->rti_ifa) != NULL) { 784 if (info->rti_ifp == NULL) 785 info->rti_ifp = ifa->ifa_ifp; 786 } else 787 error = ENETUNREACH; 788 return (error); 789 } 790 791 /* 792 * Expunges references to a route that's about to be reclaimed. 793 * The route must be locked. 794 */ 795 int 796 rtexpunge(struct rtentry *rt) 797 { 798 struct radix_node *rn; 799 struct radix_node_head *rnh; 800 struct ifaddr *ifa; 801 int error = 0; 802 803 rnh = rt_tables[rt->rt_fibnum][rt_key(rt)->sa_family]; 804 RT_LOCK_ASSERT(rt); 805 RADIX_NODE_HEAD_LOCK_ASSERT(rnh); 806 #if 0 807 /* 808 * We cannot assume anything about the reference count 809 * because protocols call us in many situations; often 810 * before unwinding references to the table entry. 811 */ 812 KASSERT(rt->rt_refcnt <= 1, ("bogus refcnt %ld", rt->rt_refcnt)); 813 #endif 814 /* 815 * Find the correct routing tree to use for this Address Family 816 */ 817 rnh = rt_tables[rt->rt_fibnum][rt_key(rt)->sa_family]; 818 if (rnh == NULL) 819 return (EAFNOSUPPORT); 820 821 /* 822 * Remove the item from the tree; it should be there, 823 * but when callers invoke us blindly it may not (sigh). 824 */ 825 rn = rnh->rnh_deladdr(rt_key(rt), rt_mask(rt), rnh); 826 if (rn == NULL) { 827 error = ESRCH; 828 goto bad; 829 } 830 KASSERT((rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) == 0, 831 ("unexpected flags 0x%x", rn->rn_flags)); 832 KASSERT(rt == RNTORT(rn), 833 ("lookup mismatch, rt %p rn %p", rt, rn)); 834 835 rt->rt_flags &= ~RTF_UP; 836 837 /* 838 * Now search what's left of the subtree for any cloned 839 * routes which might have been formed from this node. 840 */ 841 if ((rt->rt_flags & RTF_CLONING) && rt_mask(rt)) 842 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt), 843 rt_fixdelete, rt); 844 845 /* 846 * Remove any external references we may have. 847 * This might result in another rtentry being freed if 848 * we held its last reference. 849 */ 850 if (rt->rt_gwroute) { 851 RTFREE(rt->rt_gwroute); 852 rt->rt_gwroute = NULL; 853 } 854 855 /* 856 * Give the protocol a chance to keep things in sync. 857 */ 858 if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest) { 859 struct rt_addrinfo info; 860 861 bzero((caddr_t)&info, sizeof(info)); 862 info.rti_flags = rt->rt_flags; 863 info.rti_info[RTAX_DST] = rt_key(rt); 864 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 865 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 866 ifa->ifa_rtrequest(RTM_DELETE, rt, &info); 867 } 868 869 /* 870 * one more rtentry floating around that is not 871 * linked to the routing table. 872 */ 873 rttrash++; 874 bad: 875 return (error); 876 } 877 878 int 879 rtrequest1(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt) 880 { 881 return (rtrequest1_fib(req, info, ret_nrt, 0)); 882 } 883 884 int 885 rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt, 886 u_int fibnum) 887 { 888 int error = 0, needlock = 0; 889 register struct rtentry *rt; 890 register struct radix_node *rn; 891 register struct radix_node_head *rnh; 892 struct ifaddr *ifa; 893 struct sockaddr *ndst; 894 #define senderr(x) { error = x ; goto bad; } 895 896 KASSERT((fibnum < rt_numfibs), ("rtrequest1_fib: bad fibnum")); 897 if (dst->sa_family != AF_INET) /* Only INET supports > 1 fib now */ 898 fibnum = 0; 899 /* 900 * Find the correct routing tree to use for this Address Family 901 */ 902 rnh = rt_tables[fibnum][dst->sa_family]; 903 if (rnh == NULL) 904 return (EAFNOSUPPORT); 905 needlock = ((flags & RTF_RNH_LOCKED) == 0); 906 flags &= ~RTF_RNH_LOCKED; 907 if (needlock) 908 RADIX_NODE_HEAD_LOCK(rnh); 909 else 910 RADIX_NODE_HEAD_LOCK_ASSERT(rnh); 911 /* 912 * If we are adding a host route then we don't want to put 913 * a netmask in the tree, nor do we want to clone it. 914 */ 915 if (flags & RTF_HOST) { 916 netmask = NULL; 917 flags &= ~RTF_CLONING; 918 } 919 switch (req) { 920 case RTM_DELETE: 921 /* 922 * Remove the item from the tree and return it. 923 * Complain if it is not there and do no more processing. 924 */ 925 rn = rnh->rnh_deladdr(dst, netmask, rnh); 926 if (rn == NULL) 927 senderr(ESRCH); 928 if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 929 panic ("rtrequest delete"); 930 rt = RNTORT(rn); 931 RT_LOCK(rt); 932 RT_ADDREF(rt); 933 rt->rt_flags &= ~RTF_UP; 934 935 /* 936 * Now search what's left of the subtree for any cloned 937 * routes which might have been formed from this node. 938 */ 939 if ((rt->rt_flags & RTF_CLONING) && 940 rt_mask(rt)) { 941 rnh->rnh_walktree_from(rnh, dst, rt_mask(rt), 942 rt_fixdelete, rt); 943 } 944 945 /* 946 * Remove any external references we may have. 947 * This might result in another rtentry being freed if 948 * we held its last reference. 949 */ 950 if (rt->rt_gwroute) { 951 RTFREE(rt->rt_gwroute); 952 rt->rt_gwroute = NULL; 953 } 954 955 /* 956 * give the protocol a chance to keep things in sync. 957 */ 958 if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest) 959 ifa->ifa_rtrequest(RTM_DELETE, rt, info); 960 961 /* 962 * One more rtentry floating around that is not 963 * linked to the routing table. rttrash will be decremented 964 * when RTFREE(rt) is eventually called. 965 */ 966 rttrash++; 967 968 /* 969 * If the caller wants it, then it can have it, 970 * but it's up to it to free the rtentry as we won't be 971 * doing it. 972 */ 973 if (ret_nrt) { 974 *ret_nrt = rt; 975 RT_UNLOCK(rt); 976 } else 977 RTFREE_LOCKED(rt); 978 break; 979 980 case RTM_RESOLVE: 981 if (ret_nrt == NULL || (rt = *ret_nrt) == NULL) 982 senderr(EINVAL); 983 ifa = rt->rt_ifa; 984 /* XXX locking? */ 985 flags = rt->rt_flags & 986 ~(RTF_CLONING | RTF_STATIC); 987 flags |= RTF_WASCLONED; 988 gateway = rt->rt_gateway; 989 if ((netmask = rt->rt_genmask) == NULL) 990 flags |= RTF_HOST; 991 goto makeroute; 992 993 case RTM_ADD: 994 if ((flags & RTF_GATEWAY) && !gateway) 995 senderr(EINVAL); 996 if (dst && gateway && (dst->sa_family != gateway->sa_family) && 997 (gateway->sa_family != AF_UNSPEC) && (gateway->sa_family != AF_LINK)) 998 senderr(EINVAL); 999 1000 if (info->rti_ifa == NULL && (error = rt_getifa_fib(info, fibnum))) 1001 senderr(error); 1002 ifa = info->rti_ifa; 1003 1004 makeroute: 1005 rt = uma_zalloc(rtzone, M_NOWAIT | M_ZERO); 1006 if (rt == NULL) 1007 senderr(ENOBUFS); 1008 RT_LOCK_INIT(rt); 1009 rt->rt_flags = RTF_UP | flags; 1010 rt->rt_fibnum = fibnum; 1011 /* 1012 * Add the gateway. Possibly re-malloc-ing the storage for it 1013 * also add the rt_gwroute if possible. 1014 */ 1015 RT_LOCK(rt); 1016 if ((error = rt_setgate(rt, dst, gateway)) != 0) { 1017 RT_LOCK_DESTROY(rt); 1018 uma_zfree(rtzone, rt); 1019 senderr(error); 1020 } 1021 1022 /* 1023 * point to the (possibly newly malloc'd) dest address. 1024 */ 1025 ndst = (struct sockaddr *)rt_key(rt); 1026 1027 /* 1028 * make sure it contains the value we want (masked if needed). 1029 */ 1030 if (netmask) { 1031 rt_maskedcopy(dst, ndst, netmask); 1032 } else 1033 bcopy(dst, ndst, dst->sa_len); 1034 1035 /* 1036 * Note that we now have a reference to the ifa. 1037 * This moved from below so that rnh->rnh_addaddr() can 1038 * examine the ifa and ifa->ifa_ifp if it so desires. 1039 */ 1040 IFAREF(ifa); 1041 rt->rt_ifa = ifa; 1042 rt->rt_ifp = ifa->ifa_ifp; 1043 1044 /* XXX mtu manipulation will be done in rnh_addaddr -- itojun */ 1045 rn = rnh->rnh_addaddr(ndst, netmask, rnh, rt->rt_nodes); 1046 if (rn == NULL) { 1047 struct rtentry *rt2; 1048 /* 1049 * Uh-oh, we already have one of these in the tree. 1050 * We do a special hack: if the route that's already 1051 * there was generated by the cloning mechanism 1052 * then we just blow it away and retry the insertion 1053 * of the new one. 1054 */ 1055 rt2 = rtalloc1_fib(dst, 0, RTF_RNH_LOCKED, fibnum); 1056 if (rt2 && rt2->rt_parent) { 1057 rtexpunge(rt2); 1058 RT_UNLOCK(rt2); 1059 rn = rnh->rnh_addaddr(ndst, netmask, 1060 rnh, rt->rt_nodes); 1061 } else if (rt2) { 1062 /* undo the extra ref we got */ 1063 RTFREE_LOCKED(rt2); 1064 } 1065 } 1066 1067 /* 1068 * If it still failed to go into the tree, 1069 * then un-make it (this should be a function) 1070 */ 1071 if (rn == NULL) { 1072 if (rt->rt_gwroute) 1073 RTFREE(rt->rt_gwroute); 1074 if (rt->rt_ifa) 1075 IFAFREE(rt->rt_ifa); 1076 Free(rt_key(rt)); 1077 RT_LOCK_DESTROY(rt); 1078 uma_zfree(rtzone, rt); 1079 senderr(EEXIST); 1080 } 1081 1082 rt->rt_parent = NULL; 1083 1084 /* 1085 * If we got here from RESOLVE, then we are cloning 1086 * so clone the rest, and note that we 1087 * are a clone (and increment the parent's references) 1088 */ 1089 if (req == RTM_RESOLVE) { 1090 KASSERT(ret_nrt && *ret_nrt, 1091 ("no route to clone from")); 1092 rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */ 1093 rt->rt_rmx.rmx_pksent = 0; /* reset packet counter */ 1094 if ((*ret_nrt)->rt_flags & RTF_CLONING) { 1095 /* 1096 * NB: We do not bump the refcnt on the parent 1097 * entry under the assumption that it will 1098 * remain so long as we do. This is 1099 * important when deleting the parent route 1100 * as this operation requires traversing 1101 * the tree to delete all clones and futzing 1102 * with refcnts requires us to double-lock 1103 * parent through this back reference. 1104 */ 1105 rt->rt_parent = *ret_nrt; 1106 } 1107 } 1108 1109 /* 1110 * If this protocol has something to add to this then 1111 * allow it to do that as well. 1112 */ 1113 if (ifa->ifa_rtrequest) 1114 ifa->ifa_rtrequest(req, rt, info); 1115 1116 /* 1117 * We repeat the same procedure from rt_setgate() here because 1118 * it doesn't fire when we call it there because the node 1119 * hasn't been added to the tree yet. 1120 */ 1121 if (req == RTM_ADD && 1122 !(rt->rt_flags & RTF_HOST) && rt_mask(rt) != NULL) { 1123 struct rtfc_arg arg; 1124 arg.rnh = rnh; 1125 arg.rt0 = rt; 1126 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt), 1127 rt_fixchange, &arg); 1128 } 1129 1130 /* 1131 * actually return a resultant rtentry and 1132 * give the caller a single reference. 1133 */ 1134 if (ret_nrt) { 1135 *ret_nrt = rt; 1136 RT_ADDREF(rt); 1137 } 1138 RT_UNLOCK(rt); 1139 break; 1140 default: 1141 error = EOPNOTSUPP; 1142 } 1143 bad: 1144 if (needlock) 1145 RADIX_NODE_HEAD_UNLOCK(rnh); 1146 return (error); 1147 #undef senderr 1148 } 1149 1150 #undef dst 1151 #undef gateway 1152 #undef netmask 1153 #undef ifaaddr 1154 #undef ifpaddr 1155 #undef flags 1156 1157 /* 1158 * Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family'' 1159 * (i.e., the routes related to it by the operation of cloning). This 1160 * routine is iterated over all potential former-child-routes by way of 1161 * rnh->rnh_walktree_from() above, and those that actually are children of 1162 * the late parent (passed in as VP here) are themselves deleted. 1163 */ 1164 static int 1165 rt_fixdelete(struct radix_node *rn, void *vp) 1166 { 1167 struct rtentry *rt = RNTORT(rn); 1168 struct rtentry *rt0 = vp; 1169 1170 if (rt->rt_parent == rt0 && 1171 !(rt->rt_flags & (RTF_PINNED | RTF_CLONING))) { 1172 return rtrequest_fib(RTM_DELETE, rt_key(rt), NULL, rt_mask(rt), 1173 rt->rt_flags|RTF_RNH_LOCKED, NULL, rt->rt_fibnum); 1174 } 1175 return 0; 1176 } 1177 1178 /* 1179 * This routine is called from rt_setgate() to do the analogous thing for 1180 * adds and changes. There is the added complication in this case of a 1181 * middle insert; i.e., insertion of a new network route between an older 1182 * network route and (cloned) host routes. For this reason, a simple check 1183 * of rt->rt_parent is insufficient; each candidate route must be tested 1184 * against the (mask, value) of the new route (passed as before in vp) 1185 * to see if the new route matches it. 1186 * 1187 * XXX - it may be possible to do fixdelete() for changes and reserve this 1188 * routine just for adds. I'm not sure why I thought it was necessary to do 1189 * changes this way. 1190 */ 1191 1192 static int 1193 rt_fixchange(struct radix_node *rn, void *vp) 1194 { 1195 struct rtentry *rt = RNTORT(rn); 1196 struct rtfc_arg *ap = vp; 1197 struct rtentry *rt0 = ap->rt0; 1198 struct radix_node_head *rnh = ap->rnh; 1199 u_char *xk1, *xm1, *xk2, *xmp; 1200 int i, len, mlen; 1201 1202 /* make sure we have a parent, and route is not pinned or cloning */ 1203 if (!rt->rt_parent || 1204 (rt->rt_flags & (RTF_PINNED | RTF_CLONING))) 1205 return 0; 1206 1207 if (rt->rt_parent == rt0) /* parent match */ 1208 goto delete_rt; 1209 /* 1210 * There probably is a function somewhere which does this... 1211 * if not, there should be. 1212 */ 1213 len = imin(rt_key(rt0)->sa_len, rt_key(rt)->sa_len); 1214 1215 xk1 = (u_char *)rt_key(rt0); 1216 xm1 = (u_char *)rt_mask(rt0); 1217 xk2 = (u_char *)rt_key(rt); 1218 1219 /* avoid applying a less specific route */ 1220 xmp = (u_char *)rt_mask(rt->rt_parent); 1221 mlen = rt_key(rt->rt_parent)->sa_len; 1222 if (mlen > rt_key(rt0)->sa_len) /* less specific route */ 1223 return 0; 1224 for (i = rnh->rnh_treetop->rn_offset; i < mlen; i++) 1225 if ((xmp[i] & ~(xmp[i] ^ xm1[i])) != xmp[i]) 1226 return 0; /* less specific route */ 1227 1228 for (i = rnh->rnh_treetop->rn_offset; i < len; i++) 1229 if ((xk2[i] & xm1[i]) != xk1[i]) 1230 return 0; /* no match */ 1231 1232 /* 1233 * OK, this node is a clone, and matches the node currently being 1234 * changed/added under the node's mask. So, get rid of it. 1235 */ 1236 delete_rt: 1237 return rtrequest_fib(RTM_DELETE, rt_key(rt), NULL, 1238 rt_mask(rt), rt->rt_flags, NULL, rt->rt_fibnum); 1239 } 1240 1241 int 1242 rt_setgate(struct rtentry *rt, struct sockaddr *dst, struct sockaddr *gate) 1243 { 1244 /* XXX dst may be overwritten, can we move this to below */ 1245 struct radix_node_head *rnh = rt_tables[rt->rt_fibnum][dst->sa_family]; 1246 int dlen = SA_SIZE(dst), glen = SA_SIZE(gate); 1247 1248 again: 1249 RT_LOCK_ASSERT(rt); 1250 RADIX_NODE_HEAD_LOCK_ASSERT(rnh); 1251 1252 /* 1253 * A host route with the destination equal to the gateway 1254 * will interfere with keeping LLINFO in the routing 1255 * table, so disallow it. 1256 */ 1257 if (((rt->rt_flags & (RTF_HOST|RTF_GATEWAY|RTF_LLINFO)) == 1258 (RTF_HOST|RTF_GATEWAY)) && 1259 dst->sa_len == gate->sa_len && 1260 bcmp(dst, gate, dst->sa_len) == 0) { 1261 /* 1262 * The route might already exist if this is an RTM_CHANGE 1263 * or a routing redirect, so try to delete it. 1264 */ 1265 if (rt_key(rt)) 1266 rtexpunge(rt); 1267 return EADDRNOTAVAIL; 1268 } 1269 1270 /* 1271 * Cloning loop avoidance in case of bad configuration. 1272 */ 1273 if (rt->rt_flags & RTF_GATEWAY) { 1274 struct rtentry *gwrt; 1275 1276 RT_UNLOCK(rt); /* XXX workaround LOR */ 1277 gwrt = rtalloc1_fib(gate, 1, RTF_RNH_LOCKED, rt->rt_fibnum); 1278 if (gwrt == rt) { 1279 RT_REMREF(rt); 1280 return (EADDRINUSE); /* failure */ 1281 } 1282 /* 1283 * Try to reacquire the lock on rt, and if it fails, 1284 * clean state and restart from scratch. 1285 */ 1286 if (!RT_TRYLOCK(rt)) { 1287 RTFREE_LOCKED(gwrt); 1288 RT_LOCK(rt); 1289 goto again; 1290 } 1291 /* 1292 * If there is already a gwroute, then drop it. If we 1293 * are asked to replace route with itself, then do 1294 * not leak its refcounter. 1295 */ 1296 if (rt->rt_gwroute != NULL) { 1297 if (rt->rt_gwroute == gwrt) { 1298 RT_REMREF(rt->rt_gwroute); 1299 } else 1300 RTFREE(rt->rt_gwroute); 1301 } 1302 1303 if ((rt->rt_gwroute = gwrt) != NULL) 1304 RT_UNLOCK(rt->rt_gwroute); 1305 } 1306 1307 /* 1308 * Prepare to store the gateway in rt->rt_gateway. 1309 * Both dst and gateway are stored one after the other in the same 1310 * malloc'd chunk. If we have room, we can reuse the old buffer, 1311 * rt_gateway already points to the right place. 1312 * Otherwise, malloc a new block and update the 'dst' address. 1313 */ 1314 if (rt->rt_gateway == NULL || glen > SA_SIZE(rt->rt_gateway)) { 1315 caddr_t new; 1316 1317 R_Malloc(new, caddr_t, dlen + glen); 1318 if (new == NULL) 1319 return ENOBUFS; 1320 /* 1321 * XXX note, we copy from *dst and not *rt_key(rt) because 1322 * rt_setgate() can be called to initialize a newly 1323 * allocated route entry, in which case rt_key(rt) == NULL 1324 * (and also rt->rt_gateway == NULL). 1325 * Free()/free() handle a NULL argument just fine. 1326 */ 1327 bcopy(dst, new, dlen); 1328 Free(rt_key(rt)); /* free old block, if any */ 1329 rt_key(rt) = (struct sockaddr *)new; 1330 rt->rt_gateway = (struct sockaddr *)(new + dlen); 1331 } 1332 1333 /* 1334 * Copy the new gateway value into the memory chunk. 1335 */ 1336 bcopy(gate, rt->rt_gateway, glen); 1337 1338 /* 1339 * This isn't going to do anything useful for host routes, so 1340 * don't bother. Also make sure we have a reasonable mask 1341 * (we don't yet have one during adds). 1342 */ 1343 if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) { 1344 struct rtfc_arg arg; 1345 1346 arg.rnh = rnh; 1347 arg.rt0 = rt; 1348 rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt), 1349 rt_fixchange, &arg); 1350 } 1351 1352 return 0; 1353 } 1354 1355 static void 1356 rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst, struct sockaddr *netmask) 1357 { 1358 register u_char *cp1 = (u_char *)src; 1359 register u_char *cp2 = (u_char *)dst; 1360 register u_char *cp3 = (u_char *)netmask; 1361 u_char *cplim = cp2 + *cp3; 1362 u_char *cplim2 = cp2 + *cp1; 1363 1364 *cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */ 1365 cp3 += 2; 1366 if (cplim > cplim2) 1367 cplim = cplim2; 1368 while (cp2 < cplim) 1369 *cp2++ = *cp1++ & *cp3++; 1370 if (cp2 < cplim2) 1371 bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2)); 1372 } 1373 1374 /* 1375 * Set up a routing table entry, normally 1376 * for an interface. 1377 */ 1378 #define _SOCKADDR_TMPSIZE 128 /* Not too big.. kernel stack size is limited */ 1379 static inline int 1380 rtinit1(struct ifaddr *ifa, int cmd, int flags, int fibnum) 1381 { 1382 struct sockaddr *dst; 1383 struct sockaddr *netmask; 1384 struct rtentry *rt = NULL; 1385 struct rt_addrinfo info; 1386 int error = 0; 1387 int startfib, endfib; 1388 char tempbuf[_SOCKADDR_TMPSIZE]; 1389 int didwork = 0; 1390 int a_failure = 0; 1391 1392 if (flags & RTF_HOST) { 1393 dst = ifa->ifa_dstaddr; 1394 netmask = NULL; 1395 } else { 1396 dst = ifa->ifa_addr; 1397 netmask = ifa->ifa_netmask; 1398 } 1399 if ( dst->sa_family != AF_INET) 1400 fibnum = 0; 1401 if (fibnum == -1) { 1402 if (rt_add_addr_allfibs == 0 && cmd == (int)RTM_ADD) { 1403 startfib = endfib = curthread->td_proc->p_fibnum; 1404 } else { 1405 startfib = 0; 1406 endfib = rt_numfibs - 1; 1407 } 1408 } else { 1409 KASSERT((fibnum < rt_numfibs), ("rtinit1: bad fibnum")); 1410 startfib = fibnum; 1411 endfib = fibnum; 1412 } 1413 if (dst->sa_len == 0) 1414 return(EINVAL); 1415 1416 /* 1417 * If it's a delete, check that if it exists, 1418 * it's on the correct interface or we might scrub 1419 * a route to another ifa which would 1420 * be confusing at best and possibly worse. 1421 */ 1422 if (cmd == RTM_DELETE) { 1423 /* 1424 * It's a delete, so it should already exist.. 1425 * If it's a net, mask off the host bits 1426 * (Assuming we have a mask) 1427 * XXX this is kinda inet specific.. 1428 */ 1429 if (netmask != NULL) { 1430 rt_maskedcopy(dst, (struct sockaddr *)tempbuf, netmask); 1431 dst = (struct sockaddr *)tempbuf; 1432 } 1433 } 1434 /* 1435 * Now go through all the requested tables (fibs) and do the 1436 * requested action. Realistically, this will either be fib 0 1437 * for protocols that don't do multiple tables or all the 1438 * tables for those that do. XXX For this version only AF_INET. 1439 * When that changes code should be refactored to protocol 1440 * independent parts and protocol dependent parts. 1441 */ 1442 for ( fibnum = startfib; fibnum <= endfib; fibnum++) { 1443 if (cmd == RTM_DELETE) { 1444 struct radix_node_head *rnh; 1445 struct radix_node *rn; 1446 /* 1447 * Look up an rtentry that is in the routing tree and 1448 * contains the correct info. 1449 */ 1450 if ((rnh = rt_tables[fibnum][dst->sa_family]) == NULL) 1451 /* this table doesn't exist but others might */ 1452 continue; 1453 RADIX_NODE_HEAD_LOCK(rnh); 1454 rn = rnh->rnh_lookup(dst, netmask, rnh); 1455 error = (rn == NULL || 1456 (rn->rn_flags & RNF_ROOT) || 1457 RNTORT(rn)->rt_ifa != ifa || 1458 !sa_equal((struct sockaddr *)rn->rn_key, dst)); 1459 RADIX_NODE_HEAD_UNLOCK(rnh); 1460 if (error) { 1461 /* this is only an error if bad on ALL tables */ 1462 continue; 1463 } 1464 } 1465 /* 1466 * Do the actual request 1467 */ 1468 bzero((caddr_t)&info, sizeof(info)); 1469 info.rti_ifa = ifa; 1470 info.rti_flags = flags | ifa->ifa_flags; 1471 info.rti_info[RTAX_DST] = dst; 1472 info.rti_info[RTAX_GATEWAY] = ifa->ifa_addr; 1473 info.rti_info[RTAX_NETMASK] = netmask; 1474 error = rtrequest1_fib(cmd, &info, &rt, fibnum); 1475 if (error == 0 && rt != NULL) { 1476 /* 1477 * notify any listening routing agents of the change 1478 */ 1479 RT_LOCK(rt); 1480 rt_newaddrmsg_fib(cmd, ifa, error, rt, fibnum); 1481 if (cmd == RTM_DELETE) { 1482 /* 1483 * If we are deleting, and we found an entry, then 1484 * it's been removed from the tree.. now throw it away. 1485 */ 1486 RTFREE_LOCKED(rt); 1487 } else { 1488 if (cmd == RTM_ADD) { 1489 /* 1490 * We just wanted to add it.. we don't actually 1491 * need a reference. 1492 */ 1493 RT_REMREF(rt); 1494 } 1495 RT_UNLOCK(rt); 1496 } 1497 didwork = 1; 1498 } 1499 if (error) 1500 a_failure = error; 1501 } 1502 if (cmd == RTM_DELETE) { 1503 if (didwork) { 1504 error = 0; 1505 } else { 1506 /* we only give an error if it wasn't in any table */ 1507 error = ((flags & RTF_HOST) ? 1508 EHOSTUNREACH : ENETUNREACH); 1509 } 1510 } else { 1511 if (a_failure) { 1512 /* return an error if any of them failed */ 1513 error = a_failure; 1514 } 1515 } 1516 return (error); 1517 } 1518 1519 /* special one for inet internal use. may not use. */ 1520 int 1521 rtinit_fib(struct ifaddr *ifa, int cmd, int flags) 1522 { 1523 return (rtinit1(ifa, cmd, flags, -1)); 1524 } 1525 1526 /* 1527 * Set up a routing table entry, normally 1528 * for an interface. 1529 */ 1530 int 1531 rtinit(struct ifaddr *ifa, int cmd, int flags) 1532 { 1533 struct sockaddr *dst; 1534 int fib = 0; 1535 1536 if (flags & RTF_HOST) { 1537 dst = ifa->ifa_dstaddr; 1538 } else { 1539 dst = ifa->ifa_addr; 1540 } 1541 1542 if (dst->sa_family == AF_INET) 1543 fib = -1; 1544 return (rtinit1(ifa, cmd, flags, fib)); 1545 } 1546 1547 /* 1548 * rt_check() is invoked on each layer 2 output path, prior to 1549 * encapsulating outbound packets. 1550 * 1551 * The function is mostly used to find a routing entry for the gateway, 1552 * which in some protocol families could also point to the link-level 1553 * address for the gateway itself (the side effect of revalidating the 1554 * route to the destination is rather pointless at this stage, we did it 1555 * already a moment before in the pr_output() routine to locate the ifp 1556 * and gateway to use). 1557 * 1558 * When we remove the layer-3 to layer-2 mapping tables from the 1559 * routing table, this function can be removed. 1560 * 1561 * === On input === 1562 * *dst is the address of the NEXT HOP (which coincides with the 1563 * final destination if directly reachable); 1564 * *lrt0 points to the cached route to the final destination; 1565 * *lrt is not meaningful; 1566 * (*lrt0 has no ref held on it by us so REMREF is not needed. 1567 * Refs only account for major structural references and not usages, 1568 * which is actually a bit of a problem.) 1569 * 1570 * === Operation === 1571 * If the route is marked down try to find a new route. If the route 1572 * to the gateway is gone, try to setup a new route. Otherwise, 1573 * if the route is marked for packets to be rejected, enforce that. 1574 * Note that rtalloc returns an rtentry with an extra REF that we may 1575 * need to lose. 1576 * 1577 * === On return === 1578 * *dst is unchanged; 1579 * *lrt0 points to the (possibly new) route to the final destination 1580 * *lrt points to the route to the next hop [LOCKED] 1581 * 1582 * Their values are meaningful ONLY if no error is returned. 1583 * 1584 * To follow this you have to remember that: 1585 * RT_REMREF reduces the reference count by 1 but doesn't check it for 0 (!) 1586 * RTFREE_LOCKED includes an RT_REMREF (or an rtfree if refs == 1) 1587 * and an RT_UNLOCK 1588 * RTFREE does an RT_LOCK and an RTFREE_LOCKED 1589 * The gwroute pointer counts as a reference on the rtentry to which it points. 1590 * so when we add it we use the ref that rtalloc gives us and when we lose it 1591 * we need to remove the reference. 1592 * RT_TEMP_UNLOCK does an RT_ADDREF before freeing the lock, and 1593 * RT_RELOCK locks it (it can't have gone away due to the ref) and 1594 * drops the ref, possibly freeing it and zeroing the pointer if 1595 * the ref goes to 0 (unlocking in the process). 1596 */ 1597 int 1598 rt_check(struct rtentry **lrt, struct rtentry **lrt0, struct sockaddr *dst) 1599 { 1600 struct rtentry *rt; 1601 struct rtentry *rt0; 1602 u_int fibnum; 1603 1604 KASSERT(*lrt0 != NULL, ("rt_check")); 1605 rt0 = *lrt0; 1606 rt = NULL; 1607 fibnum = rt0->rt_fibnum; 1608 1609 /* NB: the locking here is tortuous... */ 1610 RT_LOCK(rt0); 1611 retry: 1612 if (rt0 && (rt0->rt_flags & RTF_UP) == 0) { 1613 /* Current rt0 is useless, try get a replacement. */ 1614 RT_UNLOCK(rt0); 1615 rt0 = NULL; 1616 } 1617 if (rt0 == NULL) { 1618 rt0 = rtalloc1_fib(dst, 1, 0UL, fibnum); 1619 if (rt0 == NULL) { 1620 return (EHOSTUNREACH); 1621 } 1622 RT_REMREF(rt0); /* don't need the reference. */ 1623 } 1624 1625 if (rt0->rt_flags & RTF_GATEWAY) { 1626 if ((rt = rt0->rt_gwroute) != NULL) { 1627 RT_LOCK(rt); /* NB: gwroute */ 1628 if ((rt->rt_flags & RTF_UP) == 0) { 1629 /* gw route is dud. ignore/lose it */ 1630 RTFREE_LOCKED(rt); /* unref (&unlock) gwroute */ 1631 rt = rt0->rt_gwroute = NULL; 1632 } 1633 } 1634 1635 if (rt == NULL) { /* NOT AN ELSE CLAUSE */ 1636 RT_TEMP_UNLOCK(rt0); /* MUST return to undo this */ 1637 rt = rtalloc1_fib(rt0->rt_gateway, 1, 0UL, fibnum); 1638 if ((rt == rt0) || (rt == NULL)) { 1639 /* the best we can do is not good enough */ 1640 if (rt) { 1641 RT_REMREF(rt); /* assumes ref > 0 */ 1642 RT_UNLOCK(rt); 1643 } 1644 RTFREE(rt0); /* lock, unref, (unlock) */ 1645 return (ENETUNREACH); 1646 } 1647 /* 1648 * Relock it and lose the added reference. All sorts 1649 * of things could have happenned while we had no 1650 * lock on it, so check for them. rt need to be 1651 * unlocked to avoid possible deadlock. 1652 */ 1653 RT_UNLOCK(rt); 1654 RT_RELOCK(rt0); 1655 if (rt0 == NULL || ((rt0->rt_flags & RTF_UP) == 0)) { 1656 /* Ru-roh.. what we had is no longer any good */ 1657 RTFREE(rt); 1658 goto retry; 1659 } 1660 /* 1661 * While we were away, someone replaced the gateway. 1662 * Since a reference count is involved we can't just 1663 * overwrite it. 1664 */ 1665 if (rt0->rt_gwroute) { 1666 if (rt0->rt_gwroute != rt) 1667 RTFREE(rt); 1668 } else { 1669 rt0->rt_gwroute = rt; 1670 } 1671 /* 1672 * Since rt was not locked, we need recheck that 1673 * it still may be used (e.g. up) 1674 */ 1675 goto retry; 1676 } 1677 RT_LOCK_ASSERT(rt); 1678 RT_UNLOCK(rt0); 1679 } else { 1680 /* think of rt as having the lock from now on.. */ 1681 rt = rt0; 1682 } 1683 /* XXX why are we inspecting rmx_expire? */ 1684 if ((rt->rt_flags & RTF_REJECT) && 1685 (rt->rt_rmx.rmx_expire == 0 || 1686 time_uptime < rt->rt_rmx.rmx_expire)) { 1687 RT_UNLOCK(rt); 1688 return (rt == rt0 ? EHOSTDOWN : EHOSTUNREACH); 1689 } 1690 1691 *lrt = rt; 1692 *lrt0 = rt0; 1693 return (0); 1694 } 1695 1696 /* This must be before ip6_init2(), which is now SI_ORDER_MIDDLE */ 1697 SYSINIT(route, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, route_init, 0);
Cache object: 8b0ca7762262c6766e0ef5a60f93dd97
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