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