sys/netinet/in.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (C) 2001 WIDE Project.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 4. Neither the name of the University nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  *
  30  *      @(#)in.c        8.4 (Berkeley) 1/9/95
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include "opt_carp.h"
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/sockio.h>
  41 #include <sys/malloc.h>
  42 #include <sys/priv.h>
  43 #include <sys/socket.h>
  44 #include <sys/kernel.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/vimage.h>
  47
  48 #include <net/if.h>
  49 #include <net/if_types.h>
  50 #include <net/route.h>
  51
  52 #include <netinet/in.h>
  53 #include <netinet/in_var.h>
  54 #include <netinet/in_pcb.h>
  55 #include <netinet/ip_var.h>
  56
  57 static int in_mask2len(struct in_addr *);
  58 static void in_len2mask(struct in_addr *, int);
  59 static int in_lifaddr_ioctl(struct socket *, u_long, caddr_t,
  60         struct ifnet *, struct thread *);
  61
  62 static int      in_addprefix(struct in_ifaddr *, int);
  63 static int      in_scrubprefix(struct in_ifaddr *);
  64 static void     in_socktrim(struct sockaddr_in *);
  65 static int      in_ifinit(struct ifnet *,
  66             struct in_ifaddr *, struct sockaddr_in *, int);
  67 static void     in_purgemaddrs(struct ifnet *);
  68
  69 static int subnetsarelocal = 0;
  70 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
  71         &subnetsarelocal, 0, "Treat all subnets as directly connected");
  72 static int sameprefixcarponly = 0;
  73 SYSCTL_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW,
  74         &sameprefixcarponly, 0,
  75         "Refuse to create same prefixes on different interfaces");
  76
  77 extern struct inpcbinfo ripcbinfo;
  78 extern struct inpcbinfo udbinfo;
  79
  80 /*
  81  * Return 1 if an internet address is for a ``local'' host
  82  * (one to which we have a connection).  If subnetsarelocal
  83  * is true, this includes other subnets of the local net.
  84  * Otherwise, it includes only the directly-connected (sub)nets.
  85  */
  86 int
  87 in_localaddr(struct in_addr in)
  88 {
  89         register u_long i = ntohl(in.s_addr);
  90         register struct in_ifaddr *ia;
  91
  92         if (V_subnetsarelocal) {
  93                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link)
  94                         if ((i & ia->ia_netmask) == ia->ia_net)
  95                                 return (1);
  96         } else {
  97                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link)
  98                         if ((i & ia->ia_subnetmask) == ia->ia_subnet)
  99                                 return (1);
 100         }
 101         return (0);
 102 }
 103
 104 /*
 105  * Return 1 if an internet address is for the local host and configured
 106  * on one of its interfaces.
 107  */
 108 int
 109 in_localip(struct in_addr in)
 110 {
 111         struct in_ifaddr *ia;
 112
 113         LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
 114                 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr)
 115                         return 1;
 116         }
 117         return 0;
 118 }
 119
 120 /*
 121  * Determine whether an IP address is in a reserved set of addresses
 122  * that may not be forwarded, or whether datagrams to that destination
 123  * may be forwarded.
 124  */
 125 int
 126 in_canforward(struct in_addr in)
 127 {
 128         register u_long i = ntohl(in.s_addr);
 129         register u_long net;
 130
 131         if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
 132                 return (0);
 133         if (IN_CLASSA(i)) {
 134                 net = i & IN_CLASSA_NET;
 135                 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
 136                         return (0);
 137         }
 138         return (1);
 139 }
 140
 141 /*
 142  * Trim a mask in a sockaddr
 143  */
 144 static void
 145 in_socktrim(struct sockaddr_in *ap)
 146 {
 147     register char *cplim = (char *) &ap->sin_addr;
 148     register char *cp = (char *) (&ap->sin_addr + 1);
 149
 150     ap->sin_len = 0;
 151     while (--cp >= cplim)
 152         if (*cp) {
 153             (ap)->sin_len = cp - (char *) (ap) + 1;
 154             break;
 155         }
 156 }
 157
 158 static int
 159 in_mask2len(mask)
 160         struct in_addr *mask;
 161 {
 162         int x, y;
 163         u_char *p;
 164
 165         p = (u_char *)mask;
 166         for (x = 0; x < sizeof(*mask); x++) {
 167                 if (p[x] != 0xff)
 168                         break;
 169         }
 170         y = 0;
 171         if (x < sizeof(*mask)) {
 172                 for (y = 0; y < 8; y++) {
 173                         if ((p[x] & (0x80 >> y)) == 0)
 174                                 break;
 175                 }
 176         }
 177         return x * 8 + y;
 178 }
 179
 180 static void
 181 in_len2mask(struct in_addr *mask, int len)
 182 {
 183         int i;
 184         u_char *p;
 185
 186         p = (u_char *)mask;
 187         bzero(mask, sizeof(*mask));
 188         for (i = 0; i < len / 8; i++)
 189                 p[i] = 0xff;
 190         if (len % 8)
 191                 p[i] = (0xff00 >> (len % 8)) & 0xff;
 192 }
 193
 194 /*
 195  * Generic internet control operations (ioctl's).
 196  * Ifp is 0 if not an interface-specific ioctl.
 197  */
 198 /* ARGSUSED */
 199 int
 200 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
 201     struct thread *td)
 202 {
 203         register struct ifreq *ifr = (struct ifreq *)data;
 204         register struct in_ifaddr *ia = 0, *iap;
 205         register struct ifaddr *ifa;
 206         struct in_addr allhosts_addr;
 207         struct in_addr dst;
 208         struct in_ifaddr *oia;
 209         struct in_aliasreq *ifra = (struct in_aliasreq *)data;
 210         struct sockaddr_in oldaddr;
 211         int error, hostIsNew, iaIsNew, maskIsNew, s;
 212         int iaIsFirst;
 213
 214         iaIsFirst = 0;
 215         iaIsNew = 0;
 216         allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
 217
 218         switch (cmd) {
 219         case SIOCALIFADDR:
 220                 if (td != NULL) {
 221                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 222                         if (error)
 223                                 return (error);
 224                 }
 225                 if (!ifp)
 226                         return EINVAL;
 227                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 228
 229         case SIOCDLIFADDR:
 230                 if (td != NULL) {
 231                         error = priv_check(td, PRIV_NET_DELIFADDR);
 232                         if (error)
 233                                 return (error);
 234                 }
 235                 if (!ifp)
 236                         return EINVAL;
 237                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 238
 239         case SIOCGLIFADDR:
 240                 if (!ifp)
 241                         return EINVAL;
 242                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 243         }
 244
 245         /*
 246          * Find address for this interface, if it exists.
 247          *
 248          * If an alias address was specified, find that one instead of
 249          * the first one on the interface, if possible.
 250          */
 251         if (ifp) {
 252                 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
 253                 LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash)
 254                         if (iap->ia_ifp == ifp &&
 255                             iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
 256                                 ia = iap;
 257                                 break;
 258                         }
 259                 if (ia == NULL)
 260                         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 261                                 iap = ifatoia(ifa);
 262                                 if (iap->ia_addr.sin_family == AF_INET) {
 263                                         ia = iap;
 264                                         break;
 265                                 }
 266                         }
 267                 if (ia == NULL)
 268                         iaIsFirst = 1;
 269         }
 270
 271         switch (cmd) {
 272
 273         case SIOCAIFADDR:
 274         case SIOCDIFADDR:
 275                 if (ifp == 0)
 276                         return (EADDRNOTAVAIL);
 277                 if (ifra->ifra_addr.sin_family == AF_INET) {
 278                         for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
 279                                 if (ia->ia_ifp == ifp  &&
 280                                     ia->ia_addr.sin_addr.s_addr ==
 281                                     ifra->ifra_addr.sin_addr.s_addr)
 282                                         break;
 283                         }
 284                         if ((ifp->if_flags & IFF_POINTOPOINT)
 285                             && (cmd == SIOCAIFADDR)
 286                             && (ifra->ifra_dstaddr.sin_addr.s_addr
 287                                 == INADDR_ANY)) {
 288                                 return EDESTADDRREQ;
 289                         }
 290                 }
 291                 if (cmd == SIOCDIFADDR && ia == 0)
 292                         return (EADDRNOTAVAIL);
 293                 /* FALLTHROUGH */
 294         case SIOCSIFADDR:
 295         case SIOCSIFNETMASK:
 296         case SIOCSIFDSTADDR:
 297                 if (td != NULL) {
 298                         error = priv_check(td, (cmd == SIOCDIFADDR) ?
 299                             PRIV_NET_DELIFADDR : PRIV_NET_ADDIFADDR);
 300                         if (error)
 301                                 return (error);
 302                 }
 303
 304                 if (ifp == 0)
 305                         return (EADDRNOTAVAIL);
 306                 if (ia == (struct in_ifaddr *)0) {
 307                         ia = (struct in_ifaddr *)
 308                                 malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO);
 309                         if (ia == (struct in_ifaddr *)NULL)
 310                                 return (ENOBUFS);
 311                         /*
 312                          * Protect from ipintr() traversing address list
 313                          * while we're modifying it.
 314                          */
 315                         s = splnet();
 316                         ifa = &ia->ia_ifa;
 317                         IFA_LOCK_INIT(ifa);
 318                         ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 319                         ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 320                         ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 321                         ifa->ifa_refcnt = 1;
 322                         TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
 323
 324                         ia->ia_sockmask.sin_len = 8;
 325                         ia->ia_sockmask.sin_family = AF_INET;
 326                         if (ifp->if_flags & IFF_BROADCAST) {
 327                                 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
 328                                 ia->ia_broadaddr.sin_family = AF_INET;
 329                         }
 330                         ia->ia_ifp = ifp;
 331
 332                         TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
 333                         splx(s);
 334                         iaIsNew = 1;
 335                 }
 336                 break;
 337
 338         case SIOCSIFBRDADDR:
 339                 if (td != NULL) {
 340                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 341                         if (error)
 342                                 return (error);
 343                 }
 344                 /* FALLTHROUGH */
 345
 346         case SIOCGIFADDR:
 347         case SIOCGIFNETMASK:
 348         case SIOCGIFDSTADDR:
 349         case SIOCGIFBRDADDR:
 350                 if (ia == (struct in_ifaddr *)0)
 351                         return (EADDRNOTAVAIL);
 352                 break;
 353         }
 354         switch (cmd) {
 355
 356         case SIOCGIFADDR:
 357                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
 358                 return (0);
 359
 360         case SIOCGIFBRDADDR:
 361                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 362                         return (EINVAL);
 363                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
 364                 return (0);
 365
 366         case SIOCGIFDSTADDR:
 367                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 368                         return (EINVAL);
 369                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
 370                 return (0);
 371
 372         case SIOCGIFNETMASK:
 373                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
 374                 return (0);
 375
 376         case SIOCSIFDSTADDR:
 377                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 378                         return (EINVAL);
 379                 oldaddr = ia->ia_dstaddr;
 380                 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
 381                 if (ifp->if_ioctl) {
 382                         IFF_LOCKGIANT(ifp);
 383                         error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
 384                             (caddr_t)ia);
 385                         IFF_UNLOCKGIANT(ifp);
 386                         if (error) {
 387                                 ia->ia_dstaddr = oldaddr;
 388                                 return (error);
 389                         }
 390                 }
 391                 if (ia->ia_flags & IFA_ROUTE) {
 392                         ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
 393                         rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
 394                         ia->ia_ifa.ifa_dstaddr =
 395                                         (struct sockaddr *)&ia->ia_dstaddr;
 396                         rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
 397                 }
 398                 return (0);
 399
 400         case SIOCSIFBRDADDR:
 401                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 402                         return (EINVAL);
 403                 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 404                 return (0);
 405
 406         case SIOCSIFADDR:
 407                 error = in_ifinit(ifp, ia,
 408                     (struct sockaddr_in *) &ifr->ifr_addr, 1);
 409                 if (error != 0 && iaIsNew)
 410                         break;
 411                 if (error == 0) {
 412                         if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
 413                                 in_addmulti(&allhosts_addr, ifp);
 414                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 415                 }
 416                 return (0);
 417
 418         case SIOCSIFNETMASK:
 419                 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
 420                 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
 421                 return (0);
 422
 423         case SIOCAIFADDR:
 424                 maskIsNew = 0;
 425                 hostIsNew = 1;
 426                 error = 0;
 427                 if (ia->ia_addr.sin_family == AF_INET) {
 428                         if (ifra->ifra_addr.sin_len == 0) {
 429                                 ifra->ifra_addr = ia->ia_addr;
 430                                 hostIsNew = 0;
 431                         } else if (ifra->ifra_addr.sin_addr.s_addr ==
 432                                                ia->ia_addr.sin_addr.s_addr)
 433                                 hostIsNew = 0;
 434                 }
 435                 if (ifra->ifra_mask.sin_len) {
 436                         in_ifscrub(ifp, ia);
 437                         ia->ia_sockmask = ifra->ifra_mask;
 438                         ia->ia_sockmask.sin_family = AF_INET;
 439                         ia->ia_subnetmask =
 440                              ntohl(ia->ia_sockmask.sin_addr.s_addr);
 441                         maskIsNew = 1;
 442                 }
 443                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 444                     (ifra->ifra_dstaddr.sin_family == AF_INET)) {
 445                         in_ifscrub(ifp, ia);
 446                         ia->ia_dstaddr = ifra->ifra_dstaddr;
 447                         maskIsNew  = 1; /* We lie; but the effect's the same */
 448                 }
 449                 if (ifra->ifra_addr.sin_family == AF_INET &&
 450                     (hostIsNew || maskIsNew))
 451                         error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
 452                 if (error != 0 && iaIsNew)
 453                         break;
 454
 455                 if ((ifp->if_flags & IFF_BROADCAST) &&
 456                     (ifra->ifra_broadaddr.sin_family == AF_INET))
 457                         ia->ia_broadaddr = ifra->ifra_broadaddr;
 458                 if (error == 0) {
 459                         if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST) != 0)
 460                                 in_addmulti(&allhosts_addr, ifp);
 461                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 462                 }
 463                 return (error);
 464
 465         case SIOCDIFADDR:
 466                 /*
 467                  * in_ifscrub kills the interface route.
 468                  */
 469                 in_ifscrub(ifp, ia);
 470                 /*
 471                  * in_ifadown gets rid of all the rest of
 472                  * the routes.  This is not quite the right
 473                  * thing to do, but at least if we are running
 474                  * a routing process they will come back.
 475                  */
 476                 in_ifadown(&ia->ia_ifa, 1);
 477                 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 478                 error = 0;
 479                 break;
 480
 481         default:
 482                 if (ifp == 0 || ifp->if_ioctl == 0)
 483                         return (EOPNOTSUPP);
 484                 IFF_LOCKGIANT(ifp);
 485                 error = (*ifp->if_ioctl)(ifp, cmd, data);
 486                 IFF_UNLOCKGIANT(ifp);
 487                 return (error);
 488         }
 489
 490         /*
 491          * Protect from ipintr() traversing address list while we're modifying
 492          * it.
 493          */
 494         s = splnet();
 495         TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
 496         TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
 497         if (ia->ia_addr.sin_family == AF_INET) {
 498                 LIST_REMOVE(ia, ia_hash);
 499                 /*
 500                  * If this is the last IPv4 address configured on this
 501                  * interface, leave the all-hosts group.
 502                  * XXX: This is quite ugly because of locking and structure.
 503                  */
 504                 oia = NULL;
 505                 IFP_TO_IA(ifp, oia);
 506                 if (oia == NULL) {
 507                         struct in_multi *inm;
 508
 509                         IFF_LOCKGIANT(ifp);
 510                         IN_MULTI_LOCK();
 511                         IN_LOOKUP_MULTI(allhosts_addr, ifp, inm);
 512                         if (inm != NULL)
 513                                 in_delmulti_locked(inm);
 514                         IN_MULTI_UNLOCK();
 515                         IFF_UNLOCKGIANT(ifp);
 516                 }
 517         }
 518         IFAFREE(&ia->ia_ifa);
 519         splx(s);
 520
 521         return (error);
 522 }
 523
 524 /*
 525  * SIOC[GAD]LIFADDR.
 526  *      SIOCGLIFADDR: get first address. (?!?)
 527  *      SIOCGLIFADDR with IFLR_PREFIX:
 528  *              get first address that matches the specified prefix.
 529  *      SIOCALIFADDR: add the specified address.
 530  *      SIOCALIFADDR with IFLR_PREFIX:
 531  *              EINVAL since we can't deduce hostid part of the address.
 532  *      SIOCDLIFADDR: delete the specified address.
 533  *      SIOCDLIFADDR with IFLR_PREFIX:
 534  *              delete the first address that matches the specified prefix.
 535  * return values:
 536  *      EINVAL on invalid parameters
 537  *      EADDRNOTAVAIL on prefix match failed/specified address not found
 538  *      other values may be returned from in_ioctl()
 539  */
 540 static int
 541 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
 542     struct ifnet *ifp, struct thread *td)
 543 {
 544         struct if_laddrreq *iflr = (struct if_laddrreq *)data;
 545         struct ifaddr *ifa;
 546
 547         /* sanity checks */
 548         if (!data || !ifp) {
 549                 panic("invalid argument to in_lifaddr_ioctl");
 550                 /*NOTRECHED*/
 551         }
 552
 553         switch (cmd) {
 554         case SIOCGLIFADDR:
 555                 /* address must be specified on GET with IFLR_PREFIX */
 556                 if ((iflr->flags & IFLR_PREFIX) == 0)
 557                         break;
 558                 /*FALLTHROUGH*/
 559         case SIOCALIFADDR:
 560         case SIOCDLIFADDR:
 561                 /* address must be specified on ADD and DELETE */
 562                 if (iflr->addr.ss_family != AF_INET)
 563                         return EINVAL;
 564                 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
 565                         return EINVAL;
 566                 /* XXX need improvement */
 567                 if (iflr->dstaddr.ss_family
 568                  && iflr->dstaddr.ss_family != AF_INET)
 569                         return EINVAL;
 570                 if (iflr->dstaddr.ss_family
 571                  && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
 572                         return EINVAL;
 573                 break;
 574         default: /*shouldn't happen*/
 575                 return EOPNOTSUPP;
 576         }
 577         if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
 578                 return EINVAL;
 579
 580         switch (cmd) {
 581         case SIOCALIFADDR:
 582             {
 583                 struct in_aliasreq ifra;
 584
 585                 if (iflr->flags & IFLR_PREFIX)
 586                         return EINVAL;
 587
 588                 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
 589                 bzero(&ifra, sizeof(ifra));
 590                 bcopy(iflr->iflr_name, ifra.ifra_name,
 591                         sizeof(ifra.ifra_name));
 592
 593                 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
 594
 595                 if (iflr->dstaddr.ss_family) {  /*XXX*/
 596                         bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
 597                                 iflr->dstaddr.ss_len);
 598                 }
 599
 600                 ifra.ifra_mask.sin_family = AF_INET;
 601                 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
 602                 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
 603
 604                 return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td);
 605             }
 606         case SIOCGLIFADDR:
 607         case SIOCDLIFADDR:
 608             {
 609                 struct in_ifaddr *ia;
 610                 struct in_addr mask, candidate, match;
 611                 struct sockaddr_in *sin;
 612
 613                 bzero(&mask, sizeof(mask));
 614                 bzero(&match, sizeof(match));
 615                 if (iflr->flags & IFLR_PREFIX) {
 616                         /* lookup a prefix rather than address. */
 617                         in_len2mask(&mask, iflr->prefixlen);
 618
 619                         sin = (struct sockaddr_in *)&iflr->addr;
 620                         match.s_addr = sin->sin_addr.s_addr;
 621                         match.s_addr &= mask.s_addr;
 622
 623                         /* if you set extra bits, that's wrong */
 624                         if (match.s_addr != sin->sin_addr.s_addr)
 625                                 return EINVAL;
 626
 627                 } else {
 628                         /* on getting an address, take the 1st match */
 629                         /* on deleting an address, do exact match */
 630                         if (cmd != SIOCGLIFADDR) {
 631                                 in_len2mask(&mask, 32);
 632                                 sin = (struct sockaddr_in *)&iflr->addr;
 633                                 match.s_addr = sin->sin_addr.s_addr;
 634                         }
 635                 }
 636
 637                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 638                         if (ifa->ifa_addr->sa_family != AF_INET6)
 639                                 continue;
 640                         if (match.s_addr == 0)
 641                                 break;
 642                         candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
 643                         candidate.s_addr &= mask.s_addr;
 644                         if (candidate.s_addr == match.s_addr)
 645                                 break;
 646                 }
 647                 if (!ifa)
 648                         return EADDRNOTAVAIL;
 649                 ia = (struct in_ifaddr *)ifa;
 650
 651                 if (cmd == SIOCGLIFADDR) {
 652                         /* fill in the if_laddrreq structure */
 653                         bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 654
 655                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 656                                 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
 657                                         ia->ia_dstaddr.sin_len);
 658                         } else
 659                                 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
 660
 661                         iflr->prefixlen =
 662                                 in_mask2len(&ia->ia_sockmask.sin_addr);
 663
 664                         iflr->flags = 0;        /*XXX*/
 665
 666                         return 0;
 667                 } else {
 668                         struct in_aliasreq ifra;
 669
 670                         /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
 671                         bzero(&ifra, sizeof(ifra));
 672                         bcopy(iflr->iflr_name, ifra.ifra_name,
 673                                 sizeof(ifra.ifra_name));
 674
 675                         bcopy(&ia->ia_addr, &ifra.ifra_addr,
 676                                 ia->ia_addr.sin_len);
 677                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 678                                 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
 679                                         ia->ia_dstaddr.sin_len);
 680                         }
 681                         bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
 682                                 ia->ia_sockmask.sin_len);
 683
 684                         return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
 685                                           ifp, td);
 686                 }
 687             }
 688         }
 689
 690         return EOPNOTSUPP;      /*just for safety*/
 691 }
 692
 693 /*
 694  * Delete any existing route for an interface.
 695  */
 696 void
 697 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
 698 {
 699
 700         in_scrubprefix(ia);
 701 }
 702
 703 /*
 704  * Initialize an interface's internet address
 705  * and routing table entry.
 706  */
 707 static int
 708 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
 709     int scrub)
 710 {
 711         register u_long i = ntohl(sin->sin_addr.s_addr);
 712         struct sockaddr_in oldaddr;
 713         int s = splimp(), flags = RTF_UP, error = 0;
 714
 715         oldaddr = ia->ia_addr;
 716         if (oldaddr.sin_family == AF_INET)
 717                 LIST_REMOVE(ia, ia_hash);
 718         ia->ia_addr = *sin;
 719         if (ia->ia_addr.sin_family == AF_INET)
 720                 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
 721                     ia, ia_hash);
 722         /*
 723          * Give the interface a chance to initialize
 724          * if this is its first address,
 725          * and to validate the address if necessary.
 726          */
 727         if (ifp->if_ioctl) {
 728                 IFF_LOCKGIANT(ifp);
 729                 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
 730                 IFF_UNLOCKGIANT(ifp);
 731                 if (error) {
 732                         splx(s);
 733                         /* LIST_REMOVE(ia, ia_hash) is done in in_control */
 734                         ia->ia_addr = oldaddr;
 735                         if (ia->ia_addr.sin_family == AF_INET)
 736                                 LIST_INSERT_HEAD(INADDR_HASH(
 737                                     ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
 738                         else
 739                                 /*
 740                                  * If oldaddr family is not AF_INET (e.g.
 741                                  * interface has been just created) in_control
 742                                  * does not call LIST_REMOVE, and we end up
 743                                  * with bogus ia entries in hash
 744                                  */
 745                                 LIST_REMOVE(ia, ia_hash);
 746                         return (error);
 747                 }
 748         }
 749         splx(s);
 750         if (scrub) {
 751                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
 752                 in_ifscrub(ifp, ia);
 753                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
 754         }
 755         if (IN_CLASSA(i))
 756                 ia->ia_netmask = IN_CLASSA_NET;
 757         else if (IN_CLASSB(i))
 758                 ia->ia_netmask = IN_CLASSB_NET;
 759         else
 760                 ia->ia_netmask = IN_CLASSC_NET;
 761         /*
 762          * The subnet mask usually includes at least the standard network part,
 763          * but may may be smaller in the case of supernetting.
 764          * If it is set, we believe it.
 765          */
 766         if (ia->ia_subnetmask == 0) {
 767                 ia->ia_subnetmask = ia->ia_netmask;
 768                 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
 769         } else
 770                 ia->ia_netmask &= ia->ia_subnetmask;
 771         ia->ia_net = i & ia->ia_netmask;
 772         ia->ia_subnet = i & ia->ia_subnetmask;
 773         in_socktrim(&ia->ia_sockmask);
 774 #ifdef DEV_CARP
 775         /*
 776          * XXX: carp(4) does not have interface route
 777          */
 778         if (ifp->if_type == IFT_CARP)
 779                 return (0);
 780 #endif
 781         /*
 782          * Add route for the network.
 783          */
 784         ia->ia_ifa.ifa_metric = ifp->if_metric;
 785         if (ifp->if_flags & IFF_BROADCAST) {
 786                 ia->ia_broadaddr.sin_addr.s_addr =
 787                         htonl(ia->ia_subnet | ~ia->ia_subnetmask);
 788                 ia->ia_netbroadcast.s_addr =
 789                         htonl(ia->ia_net | ~ ia->ia_netmask);
 790         } else if (ifp->if_flags & IFF_LOOPBACK) {
 791                 ia->ia_dstaddr = ia->ia_addr;
 792                 flags |= RTF_HOST;
 793         } else if (ifp->if_flags & IFF_POINTOPOINT) {
 794                 if (ia->ia_dstaddr.sin_family != AF_INET)
 795                         return (0);
 796                 flags |= RTF_HOST;
 797         }
 798         if ((error = in_addprefix(ia, flags)) != 0)
 799                 return (error);
 800
 801         return (error);
 802 }
 803
 804 #define rtinitflags(x) \
 805         ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
 806             ? RTF_HOST : 0)
 807 /*
 808  * Check if we have a route for the given prefix already or add one accordingly.
 809  */
 810 static int
 811 in_addprefix(struct in_ifaddr *target, int flags)
 812 {
 813         struct in_ifaddr *ia;
 814         struct in_addr prefix, mask, p, m;
 815         int error;
 816
 817         if ((flags & RTF_HOST) != 0) {
 818                 prefix = target->ia_dstaddr.sin_addr;
 819                 mask.s_addr = 0;
 820         } else {
 821                 prefix = target->ia_addr.sin_addr;
 822                 mask = target->ia_sockmask.sin_addr;
 823                 prefix.s_addr &= mask.s_addr;
 824         }
 825
 826         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 827                 if (rtinitflags(ia)) {
 828                         p = ia->ia_addr.sin_addr;
 829
 830                         if (prefix.s_addr != p.s_addr)
 831                                 continue;
 832                 } else {
 833                         p = ia->ia_addr.sin_addr;
 834                         m = ia->ia_sockmask.sin_addr;
 835                         p.s_addr &= m.s_addr;
 836
 837                         if (prefix.s_addr != p.s_addr ||
 838                             mask.s_addr != m.s_addr)
 839                                 continue;
 840                 }
 841
 842                 /*
 843                  * If we got a matching prefix route inserted by other
 844                  * interface address, we are done here.
 845                  */
 846                 if (ia->ia_flags & IFA_ROUTE) {
 847                         if (V_sameprefixcarponly &&
 848                             target->ia_ifp->if_type != IFT_CARP &&
 849                             ia->ia_ifp->if_type != IFT_CARP)
 850                                 return (EEXIST);
 851                         else
 852                                 return (0);
 853                 }
 854         }
 855
 856         /*
 857          * No-one seem to have this prefix route, so we try to insert it.
 858          */
 859         error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
 860         if (!error)
 861                 target->ia_flags |= IFA_ROUTE;
 862         return error;
 863 }
 864
 865 /*
 866  * If there is no other address in the system that can serve a route to the
 867  * same prefix, remove the route.  Hand over the route to the new address
 868  * otherwise.
 869  */
 870 static int
 871 in_scrubprefix(struct in_ifaddr *target)
 872 {
 873         struct in_ifaddr *ia;
 874         struct in_addr prefix, mask, p;
 875         int error;
 876
 877         if ((target->ia_flags & IFA_ROUTE) == 0)
 878                 return 0;
 879
 880         if (rtinitflags(target))
 881                 prefix = target->ia_dstaddr.sin_addr;
 882         else {
 883                 prefix = target->ia_addr.sin_addr;
 884                 mask = target->ia_sockmask.sin_addr;
 885                 prefix.s_addr &= mask.s_addr;
 886         }
 887
 888         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 889                 if (rtinitflags(ia))
 890                         p = ia->ia_dstaddr.sin_addr;
 891                 else {
 892                         p = ia->ia_addr.sin_addr;
 893                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
 894                 }
 895
 896                 if (prefix.s_addr != p.s_addr)
 897                         continue;
 898
 899                 /*
 900                  * If we got a matching prefix address, move IFA_ROUTE and
 901                  * the route itself to it.  Make sure that routing daemons
 902                  * get a heads-up.
 903                  *
 904                  * XXX: a special case for carp(4) interface
 905                  */
 906                 if ((ia->ia_flags & IFA_ROUTE) == 0
 907 #ifdef DEV_CARP
 908                     && (ia->ia_ifp->if_type != IFT_CARP)
 909 #endif
 910                                                         ) {
 911                         rtinit(&(target->ia_ifa), (int)RTM_DELETE,
 912                             rtinitflags(target));
 913                         target->ia_flags &= ~IFA_ROUTE;
 914
 915                         error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
 916                             rtinitflags(ia) | RTF_UP);
 917                         if (error == 0)
 918                                 ia->ia_flags |= IFA_ROUTE;
 919                         return error;
 920                 }
 921         }
 922
 923         /*
 924          * As no-one seem to have this prefix, we can remove the route.
 925          */
 926         rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
 927         target->ia_flags &= ~IFA_ROUTE;
 928         return 0;
 929 }
 930
 931 #undef rtinitflags
 932
 933 /*
 934  * Return 1 if the address might be a local broadcast address.
 935  */
 936 int
 937 in_broadcast(struct in_addr in, struct ifnet *ifp)
 938 {
 939         register struct ifaddr *ifa;
 940         u_long t;
 941
 942         if (in.s_addr == INADDR_BROADCAST ||
 943             in.s_addr == INADDR_ANY)
 944                 return 1;
 945         if ((ifp->if_flags & IFF_BROADCAST) == 0)
 946                 return 0;
 947         t = ntohl(in.s_addr);
 948         /*
 949          * Look through the list of addresses for a match
 950          * with a broadcast address.
 951          */
 952 #define ia ((struct in_ifaddr *)ifa)
 953         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
 954                 if (ifa->ifa_addr->sa_family == AF_INET &&
 955                     (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
 956                      in.s_addr == ia->ia_netbroadcast.s_addr ||
 957                      /*
 958                       * Check for old-style (host 0) broadcast.
 959                       */
 960                      t == ia->ia_subnet || t == ia->ia_net) &&
 961                      /*
 962                       * Check for an all one subnetmask. These
 963                       * only exist when an interface gets a secondary
 964                       * address.
 965                       */
 966                      ia->ia_subnetmask != (u_long)0xffffffff)
 967                             return 1;
 968         return (0);
 969 #undef ia
 970 }
 971
 972 /*
 973  * Delete all IPv4 multicast address records, and associated link-layer
 974  * multicast address records, associated with ifp.
 975  */
 976 static void
 977 in_purgemaddrs(struct ifnet *ifp)
 978 {
 979         struct in_multi *inm;
 980         struct in_multi *oinm;
 981
 982 #ifdef DIAGNOSTIC
 983         printf("%s: purging ifp %p\n", __func__, ifp);
 984 #endif
 985         IFF_LOCKGIANT(ifp);
 986         IN_MULTI_LOCK();
 987         LIST_FOREACH_SAFE(inm, &V_in_multihead, inm_link, oinm) {
 988                 if (inm->inm_ifp == ifp)
 989                         in_delmulti_locked(inm);
 990         }
 991         IN_MULTI_UNLOCK();
 992         IFF_UNLOCKGIANT(ifp);
 993 }
 994
 995 /*
 996  * On interface removal, clean up IPv4 data structures hung off of the ifnet.
 997  */
 998 void
 999 in_ifdetach(struct ifnet *ifp)
1000 {
1001
1002         in_pcbpurgeif0(&V_ripcbinfo, ifp);
1003         in_pcbpurgeif0(&V_udbinfo, ifp);
1004         in_purgemaddrs(ifp);
1005 }