1 /* 2 * Copyright (c) 1980, 1986, 1991 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)route.c 7.25 (Berkeley) 09/26/91 8 */ 9 #include "param.h" 10 #include "systm.h" 11 #include "proc.h" 12 #include "mbuf.h" 13 #include "socket.h" 14 #include "socketvar.h" 15 #include "domain.h" 16 #include "protosw.h" 17 #include "ioctl.h" 18 19 #include "if.h" 20 #include "af.h" 21 #include "route.h" 22 #include "raw_cb.h" 23 24 #include "../netinet/in.h" 25 #include "../netinet/in_var.h" 26 27 #ifdef NS 28 #include "../netns/ns.h" 29 #endif 30 #include "machine/mtpr.h" 31 #include "netisr.h" 32 33 #define SA(p) ((struct sockaddr *)(p)) 34 35 int rttrash; /* routes not in table but not freed */ 36 struct sockaddr wildcard; /* zero valued cookie for wildcard searches */ 37 int rthashsize = RTHASHSIZ; /* for netstat, etc. */ 38 39 static int rtinits_done = 0; 40 struct radix_node *rn_match(), *rn_delete(), *rn_addroute(); 41 42 rtinitheads() 43 { 44 extern struct radix_node_head *mask_rnhead; 45 if (rtinits_done == 0 && 46 #ifdef NS 47 rn_inithead(&rt_tables[AF_NS], 16) && 48 #endif 49 rn_inithead(&rt_tables[AF_INET], 32) && 50 (rt_tables[0] = mask_rnhead) != 0) 51 rtinits_done = 1; 52 } 53 54 /* 55 * Packet routing routines. 56 */ 57 rtalloc(ro) 58 register struct route *ro; 59 { 60 if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP)) 61 return; /* XXX */ 62 ro->ro_rt = rtalloc1(&ro->ro_dst, 1); 63 } 64 65 struct rtentry * 66 rtalloc1(dst, report) 67 register struct sockaddr *dst; 68 int report; 69 { 70 register struct radix_node_head *rnh = rt_tables[dst->sa_family]; 71 register struct rtentry *rt; 72 register struct radix_node *rn; 73 struct rtentry *newrt = 0; 74 int s = splnet(), err = 0, msgtype = RTM_MISS; 75 76 if (rnh && rnh->rnh_treetop && 77 (rn = rnh->rnh_match((caddr_t)dst, rnh->rnh_treetop)) && 78 ((rn->rn_flags & RNF_ROOT) == 0)) { 79 newrt = rt = (struct rtentry *)rn; 80 if (report && (rt->rt_flags & RTF_CLONING)) { 81 if ((err = rtrequest(RTM_RESOLVE, dst, SA(0), 82 SA(0), 0, &newrt)) || 83 ((rt->rt_flags & RTF_XRESOLVE) 84 && (msgtype = RTM_RESOLVE))) /* assign intended */ 85 goto miss; 86 } else 87 rt->rt_refcnt++; 88 } else { 89 rtstat.rts_unreach++; 90 miss: if (report) 91 rt_missmsg(msgtype, dst, SA(0), SA(0), SA(0), 0, err); 92 } 93 splx(s); 94 return (newrt); 95 } 96 97 rtfree(rt) 98 register struct rtentry *rt; 99 { 100 register struct ifaddr *ifa; 101 if (rt == 0) 102 panic("rtfree"); 103 rt->rt_refcnt--; 104 if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) { 105 rttrash--; 106 if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 107 panic ("rtfree 2"); 108 Free(rt_key(rt)); 109 Free(rt); 110 } 111 } 112 113 /* 114 * Force a routing table entry to the specified 115 * destination to go through the given gateway. 116 * Normally called as a result of a routing redirect 117 * message from the network layer. 118 * 119 * N.B.: must be called at splnet 120 * 121 */ 122 rtredirect(dst, gateway, netmask, flags, src, rtp) 123 struct sockaddr *dst, *gateway, *netmask, *src; 124 int flags; 125 struct rtentry **rtp; 126 { 127 register struct rtentry *rt; 128 int error = 0; 129 short *stat = 0; 130 131 /* verify the gateway is directly reachable */ 132 if (ifa_ifwithnet(gateway) == 0) { 133 error = ENETUNREACH; 134 goto done; 135 } 136 rt = rtalloc1(dst, 0); 137 /* 138 * If the redirect isn't from our current router for this dst, 139 * it's either old or wrong. If it redirects us to ourselves, 140 * we have a routing loop, perhaps as a result of an interface 141 * going down recently. 142 */ 143 #define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0) 144 if (!(flags & RTF_DONE) && rt && !equal(src, rt->rt_gateway)) 145 error = EINVAL; 146 else if (ifa_ifwithaddr(gateway)) 147 error = EHOSTUNREACH; 148 if (error) 149 goto done; 150 /* 151 * Create a new entry if we just got back a wildcard entry 152 * or the the lookup failed. This is necessary for hosts 153 * which use routing redirects generated by smart gateways 154 * to dynamically build the routing tables. 155 */ 156 if ((rt == 0) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2)) 157 goto create; 158 /* 159 * Don't listen to the redirect if it's 160 * for a route to an interface. 161 */ 162 if (rt->rt_flags & RTF_GATEWAY) { 163 if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) { 164 /* 165 * Changing from route to net => route to host. 166 * Create new route, rather than smashing route to net. 167 */ 168 create: 169 flags |= RTF_GATEWAY | RTF_DYNAMIC; 170 error = rtrequest((int)RTM_ADD, dst, gateway, 171 SA(0), flags, 172 (struct rtentry **)0); 173 stat = &rtstat.rts_dynamic; 174 } else { 175 /* 176 * Smash the current notion of the gateway to 177 * this destination. Should check about netmask!!! 178 */ 179 rt->rt_flags |= RTF_MODIFIED; 180 flags |= RTF_MODIFIED; 181 stat = &rtstat.rts_newgateway; 182 rt_setgate(rt, rt_key(rt), gateway); 183 } 184 } else 185 error = EHOSTUNREACH; 186 done: 187 if (rt) { 188 if (rtp && !error) 189 *rtp = rt; 190 else 191 rtfree(rt); 192 } 193 if (error) 194 rtstat.rts_badredirect++; 195 else 196 (stat && (*stat)++); 197 rt_missmsg(RTM_REDIRECT, dst, gateway, netmask, src, flags, error); 198 } 199 200 /* 201 * Routing table ioctl interface. 202 */ 203 rtioctl(req, data, p) 204 int req; 205 caddr_t data; 206 struct proc *p; 207 { 208 #ifndef COMPAT_43 209 return (EOPNOTSUPP); 210 #else 211 register struct ortentry *entry = (struct ortentry *)data; 212 int error; 213 struct sockaddr *netmask = 0; 214 215 if (req == SIOCADDRT) 216 req = RTM_ADD; 217 else if (req == SIOCDELRT) 218 req = RTM_DELETE; 219 else 220 return (EINVAL); 221 222 if (error = suser(p->p_ucred, &p->p_acflag)) 223 return (error); 224 #if BYTE_ORDER != BIG_ENDIAN 225 if (entry->rt_dst.sa_family == 0 && entry->rt_dst.sa_len < 16) { 226 entry->rt_dst.sa_family = entry->rt_dst.sa_len; 227 entry->rt_dst.sa_len = 16; 228 } 229 if (entry->rt_gateway.sa_family == 0 && entry->rt_gateway.sa_len < 16) { 230 entry->rt_gateway.sa_family = entry->rt_gateway.sa_len; 231 entry->rt_gateway.sa_len = 16; 232 } 233 #else 234 if (entry->rt_dst.sa_len == 0) 235 entry->rt_dst.sa_len = 16; 236 if (entry->rt_gateway.sa_len == 0) 237 entry->rt_gateway.sa_len = 16; 238 #endif 239 if ((entry->rt_flags & RTF_HOST) == 0) 240 switch (entry->rt_dst.sa_family) { 241 #ifdef INET 242 case AF_INET: 243 { 244 extern struct sockaddr_in icmpmask; 245 struct sockaddr_in *dst_in = 246 (struct sockaddr_in *)&entry->rt_dst; 247 248 in_sockmaskof(dst_in->sin_addr, &icmpmask); 249 netmask = (struct sockaddr *)&icmpmask; 250 } 251 break; 252 #endif 253 #ifdef NS 254 case AF_NS: 255 { 256 extern struct sockaddr_ns ns_netmask; 257 netmask = (struct sockaddr *)&ns_netmask; 258 } 259 #endif 260 } 261 error = rtrequest(req, &(entry->rt_dst), &(entry->rt_gateway), netmask, 262 entry->rt_flags, (struct rtentry **)0); 263 rt_missmsg((req == RTM_ADD ? RTM_OLDADD : RTM_OLDDEL), 264 &(entry->rt_dst), &(entry->rt_gateway), 265 netmask, SA(0), entry->rt_flags, error); 266 return (error); 267 #endif 268 } 269 270 struct ifaddr * 271 ifa_ifwithroute(flags, dst, gateway) 272 int flags; 273 struct sockaddr *dst, *gateway; 274 { 275 register struct ifaddr *ifa; 276 if ((flags & RTF_GATEWAY) == 0) { 277 /* 278 * If we are adding a route to an interface, 279 * and the interface is a pt to pt link 280 * we should search for the destination 281 * as our clue to the interface. Otherwise 282 * we can use the local address. 283 */ 284 ifa = 0; 285 if (flags & RTF_HOST) 286 ifa = ifa_ifwithdstaddr(dst); 287 if (ifa == 0) 288 ifa = ifa_ifwithaddr(gateway); 289 } else { 290 /* 291 * If we are adding a route to a remote net 292 * or host, the gateway may still be on the 293 * other end of a pt to pt link. 294 */ 295 ifa = ifa_ifwithdstaddr(gateway); 296 } 297 if (ifa == 0) 298 ifa = ifa_ifwithnet(gateway); 299 if (ifa == 0) { 300 struct rtentry *rt = rtalloc1(dst, 0); 301 if (rt == 0) 302 return (0); 303 rt->rt_refcnt--; 304 if ((ifa = rt->rt_ifa) == 0) 305 return (0); 306 } 307 if (ifa->ifa_addr->sa_family != dst->sa_family) { 308 struct ifaddr *oifa = ifa, *ifaof_ifpforaddr(); 309 ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp); 310 if (ifa == 0) 311 ifa = oifa; 312 } 313 return (ifa); 314 } 315 316 #define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 317 318 rtrequest(req, dst, gateway, netmask, flags, ret_nrt) 319 int req, flags; 320 struct sockaddr *dst, *gateway, *netmask; 321 struct rtentry **ret_nrt; 322 { 323 int s = splnet(); int error = 0; 324 register struct rtentry *rt; 325 register struct radix_node *rn; 326 register struct radix_node_head *rnh; 327 struct ifaddr *ifa, *ifa_ifwithdstaddr(); 328 struct sockaddr *ndst; 329 #define senderr(x) { error = x ; goto bad; } 330 331 if (rtinits_done == 0) 332 rtinitheads(); 333 if ((rnh = rt_tables[dst->sa_family]) == 0) 334 senderr(ESRCH); 335 if (flags & RTF_HOST) 336 netmask = 0; 337 switch (req) { 338 case RTM_DELETE: 339 if ((rn = rnh->rnh_delete((caddr_t)dst, (caddr_t)netmask, 340 rnh->rnh_treetop)) == 0) 341 senderr(ESRCH); 342 if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT)) 343 panic ("rtrequest delete"); 344 rt = (struct rtentry *)rn; 345 rt->rt_flags &= ~RTF_UP; 346 if (rt->rt_gwroute) { 347 rt = rt->rt_gwroute; RTFREE(rt); 348 (rt = (struct rtentry *)rn)->rt_gwroute = 0; 349 } 350 if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest) 351 ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0)); 352 rttrash++; 353 if (rt->rt_refcnt <= 0) 354 rtfree(rt); 355 break; 356 357 case RTM_RESOLVE: 358 if (ret_nrt == 0 || (rt = *ret_nrt) == 0) 359 senderr(EINVAL); 360 ifa = rt->rt_ifa; 361 flags = rt->rt_flags & ~RTF_CLONING; 362 gateway = rt->rt_gateway; 363 if ((netmask = rt->rt_genmask) == 0) 364 flags |= RTF_HOST; 365 goto makeroute; 366 367 case RTM_ADD: 368 if ((ifa = ifa_ifwithroute(flags, dst, gateway)) == 0) 369 senderr(ENETUNREACH); 370 makeroute: 371 R_Malloc(rt, struct rtentry *, sizeof(*rt)); 372 if (rt == 0) 373 senderr(ENOBUFS); 374 Bzero(rt, sizeof(*rt)); 375 rt->rt_flags = RTF_UP | flags; 376 if (rt_setgate(rt, dst, gateway)) { 377 Free(rt); 378 senderr(ENOBUFS); 379 } 380 ndst = rt_key(rt); 381 if (netmask) { 382 rt_maskedcopy(dst, ndst, netmask); 383 } else 384 Bcopy(dst, ndst, dst->sa_len); 385 rn = rnh->rnh_add((caddr_t)ndst, (caddr_t)netmask, 386 rnh->rnh_treetop, rt->rt_nodes); 387 if (rn == 0) { 388 if (rt->rt_gwroute) 389 rtfree(rt->rt_gwroute); 390 Free(rt_key(rt)); 391 Free(rt); 392 senderr(EEXIST); 393 } 394 rt->rt_ifa = ifa; 395 rt->rt_ifp = ifa->ifa_ifp; 396 if (req == RTM_RESOLVE) 397 rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */ 398 if (ifa->ifa_rtrequest) 399 ifa->ifa_rtrequest(req, rt, SA(ret_nrt ? *ret_nrt : 0)); 400 if (ret_nrt) { 401 *ret_nrt = rt; 402 rt->rt_refcnt++; 403 } 404 break; 405 } 406 bad: 407 splx(s); 408 return (error); 409 } 410 411 rt_setgate(rt0, dst, gate) 412 struct rtentry *rt0; 413 struct sockaddr *dst, *gate; 414 { 415 caddr_t new, old; 416 int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len); 417 register struct rtentry *rt = rt0; 418 419 if (rt->rt_gateway == 0 || glen > ROUNDUP(rt->rt_gateway->sa_len)) { 420 old = (caddr_t)rt_key(rt); 421 R_Malloc(new, caddr_t, dlen + glen); 422 if (new == 0) 423 return 1; 424 rt->rt_nodes->rn_key = new; 425 } else { 426 new = rt->rt_nodes->rn_key; 427 old = 0; 428 } 429 Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen); 430 if (old) { 431 Bcopy(dst, new, dlen); 432 Free(old); 433 } 434 if (rt->rt_gwroute) { 435 rt = rt->rt_gwroute; RTFREE(rt); 436 rt = rt0; rt->rt_gwroute = 0; 437 } 438 if (rt->rt_flags & RTF_GATEWAY) { 439 rt->rt_gwroute = rtalloc1(gate, 1); 440 } 441 return 0; 442 } 443 444 rt_maskedcopy(src, dst, netmask) 445 struct sockaddr *src, *dst, *netmask; 446 { 447 register u_char *cp1 = (u_char *)src; 448 register u_char *cp2 = (u_char *)dst; 449 register u_char *cp3 = (u_char *)netmask; 450 u_char *cplim = cp2 + *cp3; 451 u_char *cplim2 = cp2 + *cp1; 452 453 *cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */ 454 cp3 += 2; 455 if (cplim > cplim2) 456 cplim = cplim2; 457 while (cp2 < cplim) 458 *cp2++ = *cp1++ & *cp3++; 459 if (cp2 < cplim2) 460 bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2)); 461 } 462 /* 463 * Set up a routing table entry, normally 464 * for an interface. 465 */ 466 rtinit(ifa, cmd, flags) 467 register struct ifaddr *ifa; 468 int cmd, flags; 469 { 470 register struct rtentry *rt; 471 register struct sockaddr *dst; 472 register struct sockaddr *deldst; 473 struct mbuf *m = 0; 474 int error; 475 476 dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr; 477 if (rt = ifa->ifa_rt) { 478 rtfree(rt); 479 ifa->ifa_rt = 0; 480 } 481 if (cmd == RTM_DELETE) { 482 if ((flags & RTF_HOST) == 0 && ifa->ifa_netmask) { 483 m = m_get(M_WAIT, MT_SONAME); 484 deldst = mtod(m, struct sockaddr *); 485 rt_maskedcopy(dst, deldst, ifa->ifa_netmask); 486 dst = deldst; 487 } 488 if (rt = rtalloc1(dst, 0)) { 489 rt->rt_refcnt--; 490 if (rt->rt_ifa != ifa) { 491 if (m) 492 (void) m_free(m); 493 return (flags & RTF_HOST ? EHOSTUNREACH 494 : ENETUNREACH); 495 } 496 } 497 } 498 error = rtrequest(cmd, dst, ifa->ifa_addr, ifa->ifa_netmask, 499 flags | ifa->ifa_flags, &ifa->ifa_rt); 500 if (m) 501 (void) m_free(m); 502 if (cmd == RTM_ADD && error == 0 && (rt = ifa->ifa_rt) 503 && rt->rt_ifa != ifa) { 504 rt->rt_ifa = ifa; 505 rt->rt_ifp = ifa->ifa_ifp; 506 } 507 return (error); 508 } 509