in.c revision 126264
1/* 2 * Copyright (c) 1982, 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 * @(#)in.c 8.4 (Berkeley) 1/9/95 34 * $FreeBSD: head/sys/netinet/in.c 126264 2004-02-26 04:27:55Z mlaier $ 35 */ 36 37#include <sys/param.h> 38#include <sys/systm.h> 39#include <sys/sockio.h> 40#include <sys/malloc.h> 41#include <sys/socket.h> 42#include <sys/kernel.h> 43#include <sys/sysctl.h> 44 45#include <net/if.h> 46#include <net/if_types.h> 47#include <net/route.h> 48 49#include <netinet/in.h> 50#include <netinet/in_var.h> 51#include <netinet/in_pcb.h> 52 53#include <netinet/igmp_var.h> 54 55static MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address"); 56 57static int in_mask2len(struct in_addr *); 58static void in_len2mask(struct in_addr *, int); 59static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t, 60 struct ifnet *, struct thread *); 61 62static void in_socktrim(struct sockaddr_in *); 63static int in_ifinit(struct ifnet *, 64 struct in_ifaddr *, struct sockaddr_in *, int); 65 66static int subnetsarelocal = 0; 67SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW, 68 &subnetsarelocal, 0, "Treat all subnets as directly connected"); 69 70struct in_multihead in_multihead; /* XXX BSS initialization */ 71 72extern struct inpcbinfo ripcbinfo; 73extern struct inpcbinfo udbinfo; 74 75/* 76 * Return 1 if an internet address is for a ``local'' host 77 * (one to which we have a connection). If subnetsarelocal 78 * is true, this includes other subnets of the local net. 79 * Otherwise, it includes only the directly-connected (sub)nets. 80 */ 81int 82in_localaddr(in) 83 struct in_addr in; 84{ 85 register u_long i = ntohl(in.s_addr); 86 register struct in_ifaddr *ia; 87 88 if (subnetsarelocal) { 89 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) 90 if ((i & ia->ia_netmask) == ia->ia_net) 91 return (1); 92 } else { 93 TAILQ_FOREACH(ia, &in_ifaddrhead, ia_link) 94 if ((i & ia->ia_subnetmask) == ia->ia_subnet) 95 return (1); 96 } 97 return (0); 98} 99 100/* 101 * Determine whether an IP address is in a reserved set of addresses 102 * that may not be forwarded, or whether datagrams to that destination 103 * may be forwarded. 104 */ 105int 106in_canforward(in) 107 struct in_addr in; 108{ 109 register u_long i = ntohl(in.s_addr); 110 register u_long net; 111 112 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i)) 113 return (0); 114 if (IN_CLASSA(i)) { 115 net = i & IN_CLASSA_NET; 116 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT)) 117 return (0); 118 } 119 return (1); 120} 121 122/* 123 * Trim a mask in a sockaddr 124 */ 125static void 126in_socktrim(ap) 127struct sockaddr_in *ap; 128{ 129 register char *cplim = (char *) &ap->sin_addr; 130 register char *cp = (char *) (&ap->sin_addr + 1); 131 132 ap->sin_len = 0; 133 while (--cp >= cplim) 134 if (*cp) { 135 (ap)->sin_len = cp - (char *) (ap) + 1; 136 break; 137 } 138} 139 140static int 141in_mask2len(mask) 142 struct in_addr *mask; 143{ 144 int x, y; 145 u_char *p; 146 147 p = (u_char *)mask; 148 for (x = 0; x < sizeof(*mask); x++) { 149 if (p[x] != 0xff) 150 break; 151 } 152 y = 0; 153 if (x < sizeof(*mask)) { 154 for (y = 0; y < 8; y++) { 155 if ((p[x] & (0x80 >> y)) == 0) 156 break; 157 } 158 } 159 return x * 8 + y; 160} 161 162static void 163in_len2mask(mask, len) 164 struct in_addr *mask; 165 int len; 166{ 167 int i; 168 u_char *p; 169 170 p = (u_char *)mask; 171 bzero(mask, sizeof(*mask)); 172 for (i = 0; i < len / 8; i++) 173 p[i] = 0xff; 174 if (len % 8) 175 p[i] = (0xff00 >> (len % 8)) & 0xff; 176} 177 178/* 179 * Generic internet control operations (ioctl's). 180 * Ifp is 0 if not an interface-specific ioctl. 181 */ 182/* ARGSUSED */ 183int 184in_control(so, cmd, data, ifp, td) 185 struct socket *so; 186 u_long cmd; 187 caddr_t data; 188 register struct ifnet *ifp; 189 struct thread *td; 190{ 191 register struct ifreq *ifr = (struct ifreq *)data; 192 register struct in_ifaddr *ia = 0, *iap; 193 register struct ifaddr *ifa; 194 struct in_addr dst; 195 struct in_ifaddr *oia; 196 struct in_aliasreq *ifra = (struct in_aliasreq *)data; 197 struct sockaddr_in oldaddr; 198 int error, hostIsNew, iaIsNew, maskIsNew, s; 199 200 iaIsNew = 0; 201 202 switch (cmd) { 203 case SIOCALIFADDR: 204 case SIOCDLIFADDR: 205 if (td && (error = suser(td)) != 0) 206 return error; 207 /*fall through*/ 208 case SIOCGLIFADDR: 209 if (!ifp) 210 return EINVAL; 211 return in_lifaddr_ioctl(so, cmd, data, ifp, td); 212 } 213 214 /* 215 * Find address for this interface, if it exists. 216 * 217 * If an alias address was specified, find that one instead of 218 * the first one on the interface, if possible. 219 */ 220 if (ifp) { 221 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr; 222 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash) 223 if (iap->ia_ifp == ifp && 224 iap->ia_addr.sin_addr.s_addr == dst.s_addr) { 225 ia = iap; 226 break; 227 } 228 if (ia == NULL) 229 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 230 iap = ifatoia(ifa); 231 if (iap->ia_addr.sin_family == AF_INET) { 232 ia = iap; 233 break; 234 } 235 } 236 } 237 238 switch (cmd) { 239 240 case SIOCAIFADDR: 241 case SIOCDIFADDR: 242 if (ifp == 0) 243 return (EADDRNOTAVAIL); 244 if (ifra->ifra_addr.sin_family == AF_INET) { 245 for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) { 246 if (ia->ia_ifp == ifp && 247 ia->ia_addr.sin_addr.s_addr == 248 ifra->ifra_addr.sin_addr.s_addr) 249 break; 250 } 251 if ((ifp->if_flags & IFF_POINTOPOINT) 252 && (cmd == SIOCAIFADDR) 253 && (ifra->ifra_dstaddr.sin_addr.s_addr 254 == INADDR_ANY)) { 255 return EDESTADDRREQ; 256 } 257 } 258 if (cmd == SIOCDIFADDR && ia == 0) 259 return (EADDRNOTAVAIL); 260 /* FALLTHROUGH */ 261 case SIOCSIFADDR: 262 case SIOCSIFNETMASK: 263 case SIOCSIFDSTADDR: 264 if (td && (error = suser(td)) != 0) 265 return error; 266 267 if (ifp == 0) 268 return (EADDRNOTAVAIL); 269 if (ia == (struct in_ifaddr *)0) { 270 ia = (struct in_ifaddr *) 271 malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO); 272 if (ia == (struct in_ifaddr *)NULL) 273 return (ENOBUFS); 274 /* 275 * Protect from ipintr() traversing address list 276 * while we're modifying it. 277 */ 278 s = splnet(); 279 TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link); 280 281 ifa = &ia->ia_ifa; 282 IFA_LOCK_INIT(ifa); 283 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr; 284 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr; 285 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask; 286 ifa->ifa_refcnt = 1; 287 TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link); 288 289 ia->ia_sockmask.sin_len = 8; 290 ia->ia_sockmask.sin_family = AF_INET; 291 if (ifp->if_flags & IFF_BROADCAST) { 292 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr); 293 ia->ia_broadaddr.sin_family = AF_INET; 294 } 295 ia->ia_ifp = ifp; 296 splx(s); 297 iaIsNew = 1; 298 } 299 break; 300 301 case SIOCSIFBRDADDR: 302 if (td && (error = suser(td)) != 0) 303 return error; 304 /* FALLTHROUGH */ 305 306 case SIOCGIFADDR: 307 case SIOCGIFNETMASK: 308 case SIOCGIFDSTADDR: 309 case SIOCGIFBRDADDR: 310 if (ia == (struct in_ifaddr *)0) 311 return (EADDRNOTAVAIL); 312 break; 313 } 314 switch (cmd) { 315 316 case SIOCGIFADDR: 317 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr; 318 return (0); 319 320 case SIOCGIFBRDADDR: 321 if ((ifp->if_flags & IFF_BROADCAST) == 0) 322 return (EINVAL); 323 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr; 324 return (0); 325 326 case SIOCGIFDSTADDR: 327 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 328 return (EINVAL); 329 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr; 330 return (0); 331 332 case SIOCGIFNETMASK: 333 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask; 334 return (0); 335 336 case SIOCSIFDSTADDR: 337 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 338 return (EINVAL); 339 oldaddr = ia->ia_dstaddr; 340 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr; 341 if (ifp->if_ioctl && (error = (*ifp->if_ioctl) 342 (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) { 343 ia->ia_dstaddr = oldaddr; 344 return (error); 345 } 346 if (ia->ia_flags & IFA_ROUTE) { 347 ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr; 348 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST); 349 ia->ia_ifa.ifa_dstaddr = 350 (struct sockaddr *)&ia->ia_dstaddr; 351 rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP); 352 } 353 return (0); 354 355 case SIOCSIFBRDADDR: 356 if ((ifp->if_flags & IFF_BROADCAST) == 0) 357 return (EINVAL); 358 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr; 359 return (0); 360 361 case SIOCSIFADDR: 362 error = in_ifinit(ifp, ia, 363 (struct sockaddr_in *) &ifr->ifr_addr, 1); 364 if (error != 0 && iaIsNew) 365 break; 366 if (error == 0) 367 EVENTHANDLER_INVOKE(ifaddr_event, ifp); 368 return (0); 369 370 case SIOCSIFNETMASK: 371 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr; 372 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr); 373 return (0); 374 375 case SIOCAIFADDR: 376 maskIsNew = 0; 377 hostIsNew = 1; 378 error = 0; 379 if (ia->ia_addr.sin_family == AF_INET) { 380 if (ifra->ifra_addr.sin_len == 0) { 381 ifra->ifra_addr = ia->ia_addr; 382 hostIsNew = 0; 383 } else if (ifra->ifra_addr.sin_addr.s_addr == 384 ia->ia_addr.sin_addr.s_addr) 385 hostIsNew = 0; 386 } 387 if (ifra->ifra_mask.sin_len) { 388 in_ifscrub(ifp, ia); 389 ia->ia_sockmask = ifra->ifra_mask; 390 ia->ia_sockmask.sin_family = AF_INET; 391 ia->ia_subnetmask = 392 ntohl(ia->ia_sockmask.sin_addr.s_addr); 393 maskIsNew = 1; 394 } 395 if ((ifp->if_flags & IFF_POINTOPOINT) && 396 (ifra->ifra_dstaddr.sin_family == AF_INET)) { 397 in_ifscrub(ifp, ia); 398 ia->ia_dstaddr = ifra->ifra_dstaddr; 399 maskIsNew = 1; /* We lie; but the effect's the same */ 400 } 401 if (ifra->ifra_addr.sin_family == AF_INET && 402 (hostIsNew || maskIsNew)) 403 error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0); 404 if (error != 0 && iaIsNew) 405 break; 406 407 if ((ifp->if_flags & IFF_BROADCAST) && 408 (ifra->ifra_broadaddr.sin_family == AF_INET)) 409 ia->ia_broadaddr = ifra->ifra_broadaddr; 410 if (error == 0) 411 EVENTHANDLER_INVOKE(ifaddr_event, ifp); 412 return (error); 413 414 case SIOCDIFADDR: 415 /* 416 * in_ifscrub kills the interface route. 417 */ 418 in_ifscrub(ifp, ia); 419 /* 420 * in_ifadown gets rid of all the rest of 421 * the routes. This is not quite the right 422 * thing to do, but at least if we are running 423 * a routing process they will come back. 424 */ 425 in_ifadown(&ia->ia_ifa, 1); 426 /* 427 * XXX horrible hack to detect that we are being called 428 * from if_detach() 429 */ 430 if (ifaddr_byindex(ifp->if_index) == NULL) { 431 in_pcbpurgeif0(&ripcbinfo, ifp); 432 in_pcbpurgeif0(&udbinfo, ifp); 433 } 434 EVENTHANDLER_INVOKE(ifaddr_event, ifp); 435 error = 0; 436 break; 437 438 default: 439 if (ifp == 0 || ifp->if_ioctl == 0) 440 return (EOPNOTSUPP); 441 return ((*ifp->if_ioctl)(ifp, cmd, data)); 442 } 443 444 /* 445 * Protect from ipintr() traversing address list while we're modifying 446 * it. 447 */ 448 s = splnet(); 449 TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link); 450 TAILQ_REMOVE(&in_ifaddrhead, ia, ia_link); 451 LIST_REMOVE(ia, ia_hash); 452 IFAFREE(&ia->ia_ifa); 453 splx(s); 454 455 return (error); 456} 457 458/* 459 * SIOC[GAD]LIFADDR. 460 * SIOCGLIFADDR: get first address. (?!?) 461 * SIOCGLIFADDR with IFLR_PREFIX: 462 * get first address that matches the specified prefix. 463 * SIOCALIFADDR: add the specified address. 464 * SIOCALIFADDR with IFLR_PREFIX: 465 * EINVAL since we can't deduce hostid part of the address. 466 * SIOCDLIFADDR: delete the specified address. 467 * SIOCDLIFADDR with IFLR_PREFIX: 468 * delete the first address that matches the specified prefix. 469 * return values: 470 * EINVAL on invalid parameters 471 * EADDRNOTAVAIL on prefix match failed/specified address not found 472 * other values may be returned from in_ioctl() 473 */ 474static int 475in_lifaddr_ioctl(so, cmd, data, ifp, td) 476 struct socket *so; 477 u_long cmd; 478 caddr_t data; 479 struct ifnet *ifp; 480 struct thread *td; 481{ 482 struct if_laddrreq *iflr = (struct if_laddrreq *)data; 483 struct ifaddr *ifa; 484 485 /* sanity checks */ 486 if (!data || !ifp) { 487 panic("invalid argument to in_lifaddr_ioctl"); 488 /*NOTRECHED*/ 489 } 490 491 switch (cmd) { 492 case SIOCGLIFADDR: 493 /* address must be specified on GET with IFLR_PREFIX */ 494 if ((iflr->flags & IFLR_PREFIX) == 0) 495 break; 496 /*FALLTHROUGH*/ 497 case SIOCALIFADDR: 498 case SIOCDLIFADDR: 499 /* address must be specified on ADD and DELETE */ 500 if (iflr->addr.ss_family != AF_INET) 501 return EINVAL; 502 if (iflr->addr.ss_len != sizeof(struct sockaddr_in)) 503 return EINVAL; 504 /* XXX need improvement */ 505 if (iflr->dstaddr.ss_family 506 && iflr->dstaddr.ss_family != AF_INET) 507 return EINVAL; 508 if (iflr->dstaddr.ss_family 509 && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in)) 510 return EINVAL; 511 break; 512 default: /*shouldn't happen*/ 513 return EOPNOTSUPP; 514 } 515 if (sizeof(struct in_addr) * 8 < iflr->prefixlen) 516 return EINVAL; 517 518 switch (cmd) { 519 case SIOCALIFADDR: 520 { 521 struct in_aliasreq ifra; 522 523 if (iflr->flags & IFLR_PREFIX) 524 return EINVAL; 525 526 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */ 527 bzero(&ifra, sizeof(ifra)); 528 bcopy(iflr->iflr_name, ifra.ifra_name, 529 sizeof(ifra.ifra_name)); 530 531 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len); 532 533 if (iflr->dstaddr.ss_family) { /*XXX*/ 534 bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr, 535 iflr->dstaddr.ss_len); 536 } 537 538 ifra.ifra_mask.sin_family = AF_INET; 539 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in); 540 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen); 541 542 return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td); 543 } 544 case SIOCGLIFADDR: 545 case SIOCDLIFADDR: 546 { 547 struct in_ifaddr *ia; 548 struct in_addr mask, candidate, match; 549 struct sockaddr_in *sin; 550 int cmp; 551 552 bzero(&mask, sizeof(mask)); 553 if (iflr->flags & IFLR_PREFIX) { 554 /* lookup a prefix rather than address. */ 555 in_len2mask(&mask, iflr->prefixlen); 556 557 sin = (struct sockaddr_in *)&iflr->addr; 558 match.s_addr = sin->sin_addr.s_addr; 559 match.s_addr &= mask.s_addr; 560 561 /* if you set extra bits, that's wrong */ 562 if (match.s_addr != sin->sin_addr.s_addr) 563 return EINVAL; 564 565 cmp = 1; 566 } else { 567 if (cmd == SIOCGLIFADDR) { 568 /* on getting an address, take the 1st match */ 569 cmp = 0; /*XXX*/ 570 } else { 571 /* on deleting an address, do exact match */ 572 in_len2mask(&mask, 32); 573 sin = (struct sockaddr_in *)&iflr->addr; 574 match.s_addr = sin->sin_addr.s_addr; 575 576 cmp = 1; 577 } 578 } 579 580 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 581 if (ifa->ifa_addr->sa_family != AF_INET6) 582 continue; 583 if (!cmp) 584 break; 585 candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr; 586 candidate.s_addr &= mask.s_addr; 587 if (candidate.s_addr == match.s_addr) 588 break; 589 } 590 if (!ifa) 591 return EADDRNOTAVAIL; 592 ia = (struct in_ifaddr *)ifa; 593 594 if (cmd == SIOCGLIFADDR) { 595 /* fill in the if_laddrreq structure */ 596 bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len); 597 598 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) { 599 bcopy(&ia->ia_dstaddr, &iflr->dstaddr, 600 ia->ia_dstaddr.sin_len); 601 } else 602 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr)); 603 604 iflr->prefixlen = 605 in_mask2len(&ia->ia_sockmask.sin_addr); 606 607 iflr->flags = 0; /*XXX*/ 608 609 return 0; 610 } else { 611 struct in_aliasreq ifra; 612 613 /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */ 614 bzero(&ifra, sizeof(ifra)); 615 bcopy(iflr->iflr_name, ifra.ifra_name, 616 sizeof(ifra.ifra_name)); 617 618 bcopy(&ia->ia_addr, &ifra.ifra_addr, 619 ia->ia_addr.sin_len); 620 if ((ifp->if_flags & IFF_POINTOPOINT) != 0) { 621 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr, 622 ia->ia_dstaddr.sin_len); 623 } 624 bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr, 625 ia->ia_sockmask.sin_len); 626 627 return in_control(so, SIOCDIFADDR, (caddr_t)&ifra, 628 ifp, td); 629 } 630 } 631 } 632 633 return EOPNOTSUPP; /*just for safety*/ 634} 635 636/* 637 * Delete any existing route for an interface. 638 */ 639void 640in_ifscrub(ifp, ia) 641 register struct ifnet *ifp; 642 register struct in_ifaddr *ia; 643{ 644 645 if ((ia->ia_flags & IFA_ROUTE) == 0) 646 return; 647 if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT)) 648 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST); 649 else 650 rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0); 651 ia->ia_flags &= ~IFA_ROUTE; 652} 653 654/* 655 * Initialize an interface's internet address 656 * and routing table entry. 657 */ 658static int 659in_ifinit(ifp, ia, sin, scrub) 660 register struct ifnet *ifp; 661 register struct in_ifaddr *ia; 662 struct sockaddr_in *sin; 663 int scrub; 664{ 665 register u_long i = ntohl(sin->sin_addr.s_addr); 666 struct sockaddr_in oldaddr; 667 int s = splimp(), flags = RTF_UP, error = 0; 668 669 oldaddr = ia->ia_addr; 670 if (oldaddr.sin_family == AF_INET) 671 LIST_REMOVE(ia, ia_hash); 672 ia->ia_addr = *sin; 673 if (ia->ia_addr.sin_family == AF_INET) 674 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), 675 ia, ia_hash); 676 /* 677 * Give the interface a chance to initialize 678 * if this is its first address, 679 * and to validate the address if necessary. 680 */ 681 if (ifp->if_ioctl && 682 (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) { 683 splx(s); 684 /* LIST_REMOVE(ia, ia_hash) is done in in_control */ 685 ia->ia_addr = oldaddr; 686 if (ia->ia_addr.sin_family == AF_INET) 687 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), 688 ia, ia_hash); 689 return (error); 690 } 691 splx(s); 692 if (scrub) { 693 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr; 694 in_ifscrub(ifp, ia); 695 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr; 696 } 697 if (IN_CLASSA(i)) 698 ia->ia_netmask = IN_CLASSA_NET; 699 else if (IN_CLASSB(i)) 700 ia->ia_netmask = IN_CLASSB_NET; 701 else 702 ia->ia_netmask = IN_CLASSC_NET; 703 /* 704 * The subnet mask usually includes at least the standard network part, 705 * but may may be smaller in the case of supernetting. 706 * If it is set, we believe it. 707 */ 708 if (ia->ia_subnetmask == 0) { 709 ia->ia_subnetmask = ia->ia_netmask; 710 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask); 711 } else 712 ia->ia_netmask &= ia->ia_subnetmask; 713 ia->ia_net = i & ia->ia_netmask; 714 ia->ia_subnet = i & ia->ia_subnetmask; 715 in_socktrim(&ia->ia_sockmask); 716 /* 717 * Add route for the network. 718 */ 719 ia->ia_ifa.ifa_metric = ifp->if_metric; 720 if (ifp->if_flags & IFF_BROADCAST) { 721 ia->ia_broadaddr.sin_addr.s_addr = 722 htonl(ia->ia_subnet | ~ia->ia_subnetmask); 723 ia->ia_netbroadcast.s_addr = 724 htonl(ia->ia_net | ~ ia->ia_netmask); 725 } else if (ifp->if_flags & IFF_LOOPBACK) { 726 ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr; 727 flags |= RTF_HOST; 728 } else if (ifp->if_flags & IFF_POINTOPOINT) { 729 if (ia->ia_dstaddr.sin_family != AF_INET) 730 return (0); 731 flags |= RTF_HOST; 732 } 733 734 /*- 735 * Don't add host routes for interface addresses of 736 * 0.0.0.0 --> 0.255.255.255 netmask 255.0.0.0. This makes it 737 * possible to assign several such address pairs with consistent 738 * results (no host route) and is required by BOOTP. 739 * 740 * XXX: This is ugly ! There should be a way for the caller to 741 * say that they don't want a host route. 742 */ 743 if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY || 744 ia->ia_netmask != IN_CLASSA_NET || 745 ia->ia_dstaddr.sin_addr.s_addr != htonl(IN_CLASSA_HOST)) { 746 if ((error = rtinit(&ia->ia_ifa, (int)RTM_ADD, flags)) != 0) { 747 ia->ia_addr = oldaddr; 748 return (error); 749 } 750 ia->ia_flags |= IFA_ROUTE; 751 } 752 753 /* 754 * If the interface supports multicast, join the "all hosts" 755 * multicast group on that interface. 756 */ 757 if (ifp->if_flags & IFF_MULTICAST) { 758 struct in_addr addr; 759 760 addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP); 761 in_addmulti(&addr, ifp); 762 } 763 return (error); 764} 765 766 767/* 768 * Return 1 if the address might be a local broadcast address. 769 */ 770int 771in_broadcast(in, ifp) 772 struct in_addr in; 773 struct ifnet *ifp; 774{ 775 register struct ifaddr *ifa; 776 u_long t; 777 778 if (in.s_addr == INADDR_BROADCAST || 779 in.s_addr == INADDR_ANY) 780 return 1; 781 if ((ifp->if_flags & IFF_BROADCAST) == 0) 782 return 0; 783 t = ntohl(in.s_addr); 784 /* 785 * Look through the list of addresses for a match 786 * with a broadcast address. 787 */ 788#define ia ((struct in_ifaddr *)ifa) 789 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 790 if (ifa->ifa_addr->sa_family == AF_INET && 791 (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr || 792 in.s_addr == ia->ia_netbroadcast.s_addr || 793 /* 794 * Check for old-style (host 0) broadcast. 795 */ 796 t == ia->ia_subnet || t == ia->ia_net) && 797 /* 798 * Check for an all one subnetmask. These 799 * only exist when an interface gets a secondary 800 * address. 801 */ 802 ia->ia_subnetmask != (u_long)0xffffffff) 803 return 1; 804 return (0); 805#undef ia 806} 807/* 808 * Add an address to the list of IP multicast addresses for a given interface. 809 */ 810struct in_multi * 811in_addmulti(ap, ifp) 812 register struct in_addr *ap; 813 register struct ifnet *ifp; 814{ 815 register struct in_multi *inm; 816 int error; 817 struct sockaddr_in sin; 818 struct ifmultiaddr *ifma; 819 int s = splnet(); 820 821 /* 822 * Call generic routine to add membership or increment 823 * refcount. It wants addresses in the form of a sockaddr, 824 * so we build one here (being careful to zero the unused bytes). 825 */ 826 bzero(&sin, sizeof sin); 827 sin.sin_family = AF_INET; 828 sin.sin_len = sizeof sin; 829 sin.sin_addr = *ap; 830 error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma); 831 if (error) { 832 splx(s); 833 return 0; 834 } 835 836 /* 837 * If ifma->ifma_protospec is null, then if_addmulti() created 838 * a new record. Otherwise, we are done. 839 */ 840 if (ifma->ifma_protospec != 0) { 841 splx(s); 842 return ifma->ifma_protospec; 843 } 844 845 /* XXX - if_addmulti uses M_WAITOK. Can this really be called 846 at interrupt time? If so, need to fix if_addmulti. XXX */ 847 inm = (struct in_multi *)malloc(sizeof(*inm), M_IPMADDR, 848 M_NOWAIT | M_ZERO); 849 if (inm == NULL) { 850 splx(s); 851 return (NULL); 852 } 853 854 inm->inm_addr = *ap; 855 inm->inm_ifp = ifp; 856 inm->inm_ifma = ifma; 857 ifma->ifma_protospec = inm; 858 LIST_INSERT_HEAD(&in_multihead, inm, inm_link); 859 860 /* 861 * Let IGMP know that we have joined a new IP multicast group. 862 */ 863 igmp_joingroup(inm); 864 splx(s); 865 return (inm); 866} 867 868/* 869 * Delete a multicast address record. 870 */ 871void 872in_delmulti(inm) 873 register struct in_multi *inm; 874{ 875 struct ifmultiaddr *ifma = inm->inm_ifma; 876 struct in_multi my_inm; 877 int s = splnet(); 878 879 my_inm.inm_ifp = NULL ; /* don't send the leave msg */ 880 if (ifma->ifma_refcount == 1) { 881 /* 882 * No remaining claims to this record; let IGMP know that 883 * we are leaving the multicast group. 884 * But do it after the if_delmulti() which might reset 885 * the interface and nuke the packet. 886 */ 887 my_inm = *inm ; 888 ifma->ifma_protospec = 0; 889 LIST_REMOVE(inm, inm_link); 890 free(inm, M_IPMADDR); 891 } 892 /* XXX - should be separate API for when we have an ifma? */ 893 if_delmulti(ifma->ifma_ifp, ifma->ifma_addr); 894 if (my_inm.inm_ifp != NULL) 895 igmp_leavegroup(&my_inm); 896 splx(s); 897} 898