sys/netinet/in.c

   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: src/sys/netinet/in.c,v 1.44.2.14 2002/11/08 00:45:50 suz Exp $
  35  * $DragonFly: src/sys/netinet/in.c,v 1.41 2008/08/17 05:20:10 sephe Exp $
  36  */
  37
  38 #include "opt_bootp.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/sockio.h>
  43 #include <sys/malloc.h>
  44 #include <sys/proc.h>
  45 #include <sys/priv.h>
  46 #include <sys/msgport.h>
  47 #include <sys/socket.h>
  48
  49 #include <sys/kernel.h>
  50 #include <sys/sysctl.h>
  51 #include <sys/thread2.h>
  52
  53 #include <net/if.h>
  54 #include <net/if_types.h>
  55 #include <net/route.h>
  56 #include <net/netmsg2.h>
  57
  58 #include <netinet/in.h>
  59 #include <netinet/in_var.h>
  60 #include <netinet/in_pcb.h>
  61
  62 #include <netinet/igmp_var.h>
  63
  64 MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
  65
  66 static int in_mask2len (struct in_addr *);
  67 static void in_len2mask (struct in_addr *, int);
  68 static int in_lifaddr_ioctl (struct socket *, u_long, caddr_t,
  69         struct ifnet *, struct thread *);
  70
  71 static void     in_socktrim (struct sockaddr_in *);
  72 static int      in_ifinit(struct ifnet *, struct in_ifaddr *,
  73                     const struct sockaddr_in *, int);
  74
  75 static void     in_control_dispatch(struct netmsg *);
  76 static int      in_control_internal(u_long, caddr_t, struct ifnet *,
  77                     struct thread *);
  78
  79 static int      in_addprefix(struct in_ifaddr *, int);
  80 static void     in_scrubprefix(struct in_ifaddr *);
  81
  82 static int subnetsarelocal = 0;
  83 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
  84         &subnetsarelocal, 0, "");
  85
  86 struct in_multihead in_multihead; /* XXX BSS initialization */
  87
  88 extern struct inpcbinfo ripcbinfo;
  89 extern struct inpcbinfo udbinfo;
  90
  91 /*
  92  * Return 1 if an internet address is for a ``local'' host
  93  * (one to which we have a connection).  If subnetsarelocal
  94  * is true, this includes other subnets of the local net.
  95  * Otherwise, it includes only the directly-connected (sub)nets.
  96  */
  97 int
  98 in_localaddr(struct in_addr in)
  99 {
 100         u_long i = ntohl(in.s_addr);
 101         struct in_ifaddr_container *iac;
 102         struct in_ifaddr *ia;
 103
 104         if (subnetsarelocal) {
 105                 TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
 106                         ia = iac->ia;
 107
 108                         if ((i & ia->ia_netmask) == ia->ia_net)
 109                                 return (1);
 110                 }
 111         } else {
 112                 TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
 113                         ia = iac->ia;
 114
 115                         if ((i & ia->ia_subnetmask) == ia->ia_subnet)
 116                                 return (1);
 117                 }
 118         }
 119         return (0);
 120 }
 121
 122 /*
 123  * Determine whether an IP address is in a reserved set of addresses
 124  * that may not be forwarded, or whether datagrams to that destination
 125  * may be forwarded.
 126  */
 127 int
 128 in_canforward(struct in_addr in)
 129 {
 130         u_long i = ntohl(in.s_addr);
 131         u_long net;
 132
 133         if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
 134                 return (0);
 135         if (IN_CLASSA(i)) {
 136                 net = i & IN_CLASSA_NET;
 137                 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
 138                         return (0);
 139         }
 140         return (1);
 141 }
 142
 143 /*
 144  * Trim a mask in a sockaddr
 145  */
 146 static void
 147 in_socktrim(struct sockaddr_in *ap)
 148 {
 149     char *cplim = (char *) &ap->sin_addr;
 150     char *cp = (char *) (&ap->sin_addr + 1);
 151
 152     ap->sin_len = 0;
 153     while (--cp >= cplim)
 154         if (*cp) {
 155             (ap)->sin_len = cp - (char *) (ap) + 1;
 156             break;
 157         }
 158 }
 159
 160 static int
 161 in_mask2len(struct in_addr *mask)
 162 {
 163         int x, y;
 164         u_char *p;
 165
 166         p = (u_char *)mask;
 167         for (x = 0; x < sizeof *mask; x++) {
 168                 if (p[x] != 0xff)
 169                         break;
 170         }
 171         y = 0;
 172         if (x < sizeof *mask) {
 173                 for (y = 0; y < 8; y++) {
 174                         if ((p[x] & (0x80 >> y)) == 0)
 175                                 break;
 176                 }
 177         }
 178         return x * 8 + y;
 179 }
 180
 181 static void
 182 in_len2mask(struct in_addr *mask, int len)
 183 {
 184         int i;
 185         u_char *p;
 186
 187         p = (u_char *)mask;
 188         bzero(mask, sizeof *mask);
 189         for (i = 0; i < len / 8; i++)
 190                 p[i] = 0xff;
 191         if (len % 8)
 192                 p[i] = (0xff00 >> (len % 8)) & 0xff;
 193 }
 194
 195 static int in_interfaces;       /* number of external internet interfaces */
 196
 197 struct in_control_arg {
 198         u_long          cmd;
 199         caddr_t         data;
 200         struct ifnet    *ifp;
 201         struct thread   *td;
 202 };
 203
 204 static void
 205 in_control_dispatch(struct netmsg *nmsg)
 206 {
 207         struct lwkt_msg *msg = &nmsg->nm_lmsg;
 208         const struct in_control_arg *arg = msg->u.ms_resultp;
 209         int error;
 210
 211         error = in_control_internal(arg->cmd, arg->data, arg->ifp, arg->td);
 212         lwkt_replymsg(msg, error);
 213 }
 214
 215 /*
 216  * Generic internet control operations (ioctl's).
 217  * Ifp is 0 if not an interface-specific ioctl.
 218  *
 219  * NOTE! td might be NULL.
 220  */
 221 /* ARGSUSED */
 222 int
 223 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
 224            struct thread *td)
 225 {
 226         struct netmsg nmsg;
 227         struct in_control_arg arg;
 228         struct lwkt_msg *msg;
 229         int error;
 230
 231         switch (cmd) {
 232         case SIOCALIFADDR:
 233         case SIOCDLIFADDR:
 234                 if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
 235                         return error;
 236                 /* FALLTHROUGH */
 237         case SIOCGLIFADDR:
 238                 if (!ifp)
 239                         return EINVAL;
 240                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 241         }
 242
 243         KASSERT(cmd != SIOCALIFADDR && cmd != SIOCDLIFADDR,
 244                 ("recursive SIOC%cLIFADDR!\n",
 245                  cmd == SIOCDLIFADDR ? 'D' : 'A'));
 246
 247         /*
 248          * IFADDR alterations are serialized by netisr0
 249          */
 250         switch (cmd) {
 251         case SIOCSIFDSTADDR:
 252         case SIOCSIFBRDADDR:
 253         case SIOCSIFADDR:
 254         case SIOCSIFNETMASK:
 255         case SIOCAIFADDR:
 256         case SIOCDIFADDR:
 257                 bzero(&arg, sizeof(arg));
 258                 arg.cmd = cmd;
 259                 arg.data = data;
 260                 arg.ifp = ifp;
 261                 arg.td = td;
 262
 263                 netmsg_init(&nmsg, NULL, &curthread->td_msgport,
 264                             0, in_control_dispatch);
 265                 msg = &nmsg.nm_lmsg;
 266                 msg->u.ms_resultp = &arg;
 267
 268                 lwkt_domsg(cpu_portfn(0), msg, 0);
 269                 return msg->ms_error;
 270         default:
 271                 return in_control_internal(cmd, data, ifp, td);
 272         }
 273 }
 274
 275 static void
 276 in_ialink_dispatch(struct netmsg *nmsg)
 277 {
 278         struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
 279         struct in_ifaddr *ia = lmsg->u.ms_resultp;
 280         struct ifaddr_container *ifac;
 281         struct in_ifaddr_container *iac;
 282         int cpu = mycpuid;
 283
 284         crit_enter();
 285
 286         ifac = &ia->ia_ifa.ifa_containers[cpu];
 287         ASSERT_IFAC_VALID(ifac);
 288         KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD) == 0,
 289                 ("ia is on in_ifaddrheads\n"));
 290
 291         ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHEAD;
 292         iac = &ifac->ifa_proto_u.u_in_ifac;
 293         TAILQ_INSERT_TAIL(&in_ifaddrheads[cpu], iac, ia_link);
 294
 295         crit_exit();
 296
 297         ifa_forwardmsg(lmsg, cpu + 1);
 298 }
 299
 300 static void
 301 in_iaunlink_dispatch(struct netmsg *nmsg)
 302 {
 303         struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
 304         struct in_ifaddr *ia = lmsg->u.ms_resultp;
 305         struct ifaddr_container *ifac;
 306         struct in_ifaddr_container *iac;
 307         int cpu = mycpuid;
 308
 309         crit_enter();
 310
 311         ifac = &ia->ia_ifa.ifa_containers[cpu];
 312         ASSERT_IFAC_VALID(ifac);
 313         KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD,
 314                 ("ia is not on in_ifaddrheads\n"));
 315
 316         iac = &ifac->ifa_proto_u.u_in_ifac;
 317         TAILQ_REMOVE(&in_ifaddrheads[cpu], iac, ia_link);
 318         ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHEAD;
 319
 320         crit_exit();
 321
 322         ifa_forwardmsg(lmsg, cpu + 1);
 323 }
 324
 325 static void
 326 in_iahashins_dispatch(struct netmsg *nmsg)
 327 {
 328         struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
 329         struct in_ifaddr *ia = lmsg->u.ms_resultp;
 330         struct ifaddr_container *ifac;
 331         struct in_ifaddr_container *iac;
 332         int cpu = mycpuid;
 333
 334         crit_enter();
 335
 336         ifac = &ia->ia_ifa.ifa_containers[cpu];
 337         ASSERT_IFAC_VALID(ifac);
 338         KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
 339                 ("ia is on in_ifaddrhashtbls\n"));
 340
 341         ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHASH;
 342         iac = &ifac->ifa_proto_u.u_in_ifac;
 343         LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
 344                          iac, ia_hash);
 345
 346         crit_exit();
 347
 348         ifa_forwardmsg(lmsg, cpu + 1);
 349 }
 350
 351 static void
 352 in_iahashrem_dispatch(struct netmsg *nmsg)
 353 {
 354         struct lwkt_msg *lmsg = &nmsg->nm_lmsg;
 355         struct in_ifaddr *ia = lmsg->u.ms_resultp;
 356         struct ifaddr_container *ifac;
 357         struct in_ifaddr_container *iac;
 358         int cpu = mycpuid;
 359
 360         crit_enter();
 361
 362         ifac = &ia->ia_ifa.ifa_containers[cpu];
 363         ASSERT_IFAC_VALID(ifac);
 364         KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH,
 365                 ("ia is not on in_ifaddrhashtbls\n"));
 366
 367         iac = &ifac->ifa_proto_u.u_in_ifac;
 368         LIST_REMOVE(iac, ia_hash);
 369         ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHASH;
 370
 371         crit_exit();
 372
 373         ifa_forwardmsg(lmsg, cpu + 1);
 374 }
 375
 376 static void
 377 in_ialink(struct in_ifaddr *ia)
 378 {
 379         struct netmsg nmsg;
 380         struct lwkt_msg *lmsg;
 381
 382         netmsg_init(&nmsg, NULL, &curthread->td_msgport,
 383                     0, in_ialink_dispatch);
 384         lmsg = &nmsg.nm_lmsg;
 385         lmsg->u.ms_resultp = ia;
 386
 387         ifa_domsg(lmsg, 0);
 388 }
 389
 390 void
 391 in_iaunlink(struct in_ifaddr *ia)
 392 {
 393         struct netmsg nmsg;
 394         struct lwkt_msg *lmsg;
 395
 396         netmsg_init(&nmsg, NULL, &curthread->td_msgport,
 397                     0, in_iaunlink_dispatch);
 398         lmsg = &nmsg.nm_lmsg;
 399         lmsg->u.ms_resultp = ia;
 400
 401         ifa_domsg(lmsg, 0);
 402 }
 403
 404 void
 405 in_iahash_insert(struct in_ifaddr *ia)
 406 {
 407         struct netmsg nmsg;
 408         struct lwkt_msg *lmsg;
 409
 410         netmsg_init(&nmsg, NULL, &curthread->td_msgport,
 411                     0, in_iahashins_dispatch);
 412         lmsg = &nmsg.nm_lmsg;
 413         lmsg->u.ms_resultp = ia;
 414
 415         ifa_domsg(lmsg, 0);
 416 }
 417
 418 void
 419 in_iahash_remove(struct in_ifaddr *ia)
 420 {
 421         struct netmsg nmsg;
 422         struct lwkt_msg *lmsg;
 423
 424         netmsg_init(&nmsg, NULL, &curthread->td_msgport,
 425                     0, in_iahashrem_dispatch);
 426         lmsg = &nmsg.nm_lmsg;
 427         lmsg->u.ms_resultp = ia;
 428
 429         ifa_domsg(lmsg, 0);
 430 }
 431
 432 static __inline struct in_ifaddr *
 433 in_ianext(struct in_ifaddr *oia)
 434 {
 435         struct ifaddr_container *ifac;
 436         struct in_ifaddr_container *iac;
 437
 438         ifac = &oia->ia_ifa.ifa_containers[mycpuid];
 439         ASSERT_IFAC_VALID(ifac);
 440         KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD,
 441                 ("ia is not on in_ifaddrheads\n"));
 442
 443         iac = &ifac->ifa_proto_u.u_in_ifac;
 444         iac = TAILQ_NEXT(iac, ia_link);
 445         if (iac != NULL)
 446                 return iac->ia;
 447         else
 448                 return NULL;
 449 }
 450
 451 static int
 452 in_control_internal(u_long cmd, caddr_t data, struct ifnet *ifp,
 453                     struct thread *td)
 454 {
 455         struct ifreq *ifr = (struct ifreq *)data;
 456         struct in_ifaddr *ia = NULL;
 457         struct in_addr dst;
 458         struct in_aliasreq *ifra = (struct in_aliasreq *)data;
 459         struct ifaddr_container *ifac;
 460         struct in_ifaddr_container *iac;
 461         struct sockaddr_in oldaddr;
 462         int hostIsNew, iaIsNew, maskIsNew, ifpWasUp;
 463         int error = 0;
 464
 465         iaIsNew = 0;
 466         ifpWasUp = 0;
 467
 468         /*
 469          * Find address for this interface, if it exists.
 470          *
 471          * If an alias address was specified, find that one instead of
 472          * the first one on the interface, if possible
 473          */
 474         if (ifp) {
 475                 struct in_ifaddr *iap;
 476
 477                 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
 478                 LIST_FOREACH(iac, INADDR_HASH(dst.s_addr), ia_hash) {
 479                         iap = iac->ia;
 480                         if (iap->ia_ifp == ifp &&
 481                             iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
 482                                 ia = iap;
 483                                 break;
 484                         }
 485                 }
 486                 if (ia == NULL) {
 487                         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid],
 488                                       ifa_link) {
 489                                 iap = ifatoia(ifac->ifa);
 490                                 if (iap->ia_addr.sin_family == AF_INET) {
 491                                         ia = iap;
 492                                         break;
 493                                 }
 494                         }
 495                 }
 496
 497                 if (ifp->if_flags & IFF_UP)
 498                         ifpWasUp = 1;
 499         }
 500
 501         switch (cmd) {
 502         case SIOCAIFADDR:
 503         case SIOCDIFADDR:
 504                 if (ifp == NULL)
 505                         return (EADDRNOTAVAIL);
 506                 if (ifra->ifra_addr.sin_family == AF_INET) {
 507                         while (ia != NULL) {
 508                                 if (ia->ia_ifp == ifp  &&
 509                                     ia->ia_addr.sin_addr.s_addr ==
 510                                     ifra->ifra_addr.sin_addr.s_addr)
 511                                         break;
 512                                 ia = in_ianext(ia);
 513                         }
 514                         if ((ifp->if_flags & IFF_POINTOPOINT) &&
 515                             cmd == SIOCAIFADDR &&
 516                             ifra->ifra_dstaddr.sin_addr.s_addr == INADDR_ANY) {
 517                                 return EDESTADDRREQ;
 518                         }
 519                 }
 520                 if (cmd == SIOCDIFADDR && ia == NULL)
 521                         return (EADDRNOTAVAIL);
 522                 /* FALLTHROUGH */
 523         case SIOCSIFADDR:
 524         case SIOCSIFNETMASK:
 525         case SIOCSIFDSTADDR:
 526                 if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
 527                         return error;
 528
 529                 if (ifp == NULL)
 530                         return (EADDRNOTAVAIL);
 531
 532                 if (cmd == SIOCSIFDSTADDR &&
 533                     (ifp->if_flags & IFF_POINTOPOINT) == 0)
 534                         return (EINVAL);
 535
 536                 if (ia == NULL) {
 537                         struct ifaddr *ifa;
 538                         int i;
 539
 540                         ia = ifa_create(sizeof(*ia), M_WAITOK);
 541                         ifa = &ia->ia_ifa;
 542
 543                         /*
 544                          * Setup per-CPU information
 545                          */
 546                         for (i = 0; i < ncpus; ++i) {
 547                                 ifac = &ifa->ifa_containers[i];
 548                                 iac = &ifac->ifa_proto_u.u_in_ifac;
 549                                 iac->ia = ia;
 550                                 iac->ia_ifac = ifac;
 551                         }
 552
 553                         /*
 554                          * Protect from NETISR_IP traversing address list
 555                          * while we're modifying it.
 556                          */
 557                         crit_enter();
 558
 559                         in_ialink(ia);
 560                         ifa_iflink(ifa, ifp, 1);
 561
 562                         ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 563                         ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 564                         ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 565                         ia->ia_sockmask.sin_len = 8;
 566                         ia->ia_sockmask.sin_family = AF_INET;
 567                         if (ifp->if_flags & IFF_BROADCAST) {
 568                                 ia->ia_broadaddr.sin_len = sizeof ia->ia_addr;
 569                                 ia->ia_broadaddr.sin_family = AF_INET;
 570                         }
 571                         ia->ia_ifp = ifp;
 572                         if (!(ifp->if_flags & IFF_LOOPBACK))
 573                                 in_interfaces++;
 574                         iaIsNew = 1;
 575
 576                         crit_exit();
 577                 }
 578                 break;
 579
 580         case SIOCSIFBRDADDR:
 581                 if (td && (error = priv_check(td, PRIV_ROOT)) != 0)
 582                         return error;
 583                 /* FALLTHROUGH */
 584
 585         case SIOCGIFADDR:
 586         case SIOCGIFNETMASK:
 587         case SIOCGIFDSTADDR:
 588         case SIOCGIFBRDADDR:
 589                 if (ia == NULL)
 590                         return (EADDRNOTAVAIL);
 591                 break;
 592         }
 593
 594         switch (cmd) {
 595         case SIOCGIFADDR:
 596                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
 597                 return (0);
 598
 599         case SIOCGIFBRDADDR:
 600                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 601                         return (EINVAL);
 602                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
 603                 return (0);
 604
 605         case SIOCGIFDSTADDR:
 606                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 607                         return (EINVAL);
 608                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
 609                 return (0);
 610
 611         case SIOCGIFNETMASK:
 612                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
 613                 return (0);
 614
 615         case SIOCSIFDSTADDR:
 616                 KKASSERT(ifp->if_flags & IFF_POINTOPOINT);
 617
 618                 oldaddr = ia->ia_dstaddr;
 619                 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
 620                 if (ifp->if_ioctl != NULL) {
 621                         ifnet_serialize_all(ifp);
 622                         error = ifp->if_ioctl(ifp, SIOCSIFDSTADDR, (caddr_t)ia,
 623                                               td->td_proc->p_ucred);
 624                         ifnet_deserialize_all(ifp);
 625                         if (error) {
 626                                 ia->ia_dstaddr = oldaddr;
 627                                 return (error);
 628                         }
 629                 }
 630                 if (ia->ia_flags & IFA_ROUTE) {
 631                         ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
 632                         rtinit(&ia->ia_ifa, RTM_DELETE, RTF_HOST);
 633                         ia->ia_ifa.ifa_dstaddr =
 634                                         (struct sockaddr *)&ia->ia_dstaddr;
 635                         rtinit(&ia->ia_ifa, RTM_ADD, RTF_HOST | RTF_UP);
 636                 }
 637                 return (0);
 638
 639         case SIOCSIFBRDADDR:
 640                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 641                         return (EINVAL);
 642                 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 643                 return (0);
 644
 645         case SIOCSIFADDR:
 646                 error = in_ifinit(ifp, ia,
 647                     (const struct sockaddr_in *)&ifr->ifr_addr, 1);
 648                 if (error != 0 && iaIsNew)
 649                         break;
 650                 if (error == 0) {
 651                         EVENTHANDLER_INVOKE(ifaddr_event, ifp,
 652                         iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
 653                         &ia->ia_ifa);
 654                 }
 655                 if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
 656                         /*
 657                          * Interface is brought up by in_ifinit()
 658                          * (via ifp->if_ioctl).  We act as if the
 659                          * interface got IFF_UP flag turned on.
 660                          */
 661                         if_up(ifp);
 662                 }
 663                 return (0);
 664
 665         case SIOCSIFNETMASK:
 666                 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
 667                 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
 668                 return (0);
 669
 670         case SIOCAIFADDR:
 671                 maskIsNew = 0;
 672                 hostIsNew = 1;
 673                 error = 0;
 674                 if (ia->ia_addr.sin_family == AF_INET) {
 675                         if (ifra->ifra_addr.sin_len == 0) {
 676                                 ifra->ifra_addr = ia->ia_addr;
 677                                 hostIsNew = 0;
 678                         } else if (ifra->ifra_addr.sin_addr.s_addr ==
 679                                    ia->ia_addr.sin_addr.s_addr) {
 680                                 hostIsNew = 0;
 681                         }
 682                 }
 683                 if (ifra->ifra_mask.sin_len) {
 684                         in_ifscrub(ifp, ia);
 685                         ia->ia_sockmask = ifra->ifra_mask;
 686                         ia->ia_sockmask.sin_family = AF_INET;
 687                         ia->ia_subnetmask =
 688                             ntohl(ia->ia_sockmask.sin_addr.s_addr);
 689                         maskIsNew = 1;
 690                 }
 691                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 692                     ifra->ifra_dstaddr.sin_family == AF_INET) {
 693                         in_ifscrub(ifp, ia);
 694                         ia->ia_dstaddr = ifra->ifra_dstaddr;
 695                         maskIsNew  = 1; /* We lie; but the effect's the same */
 696                 }
 697                 if (ifra->ifra_addr.sin_family == AF_INET &&
 698                     (hostIsNew || maskIsNew))
 699                         error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
 700
 701                 if (error != 0 && iaIsNew)
 702                         break;
 703
 704                 if ((ifp->if_flags & IFF_BROADCAST) &&
 705                     ifra->ifra_broadaddr.sin_family == AF_INET)
 706                         ia->ia_broadaddr = ifra->ifra_broadaddr;
 707                 if (error == 0) {
 708                         EVENTHANDLER_INVOKE(ifaddr_event, ifp,
 709                         iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
 710                         &ia->ia_ifa);
 711                 }
 712                 if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
 713                         /* See the comment in SIOCSIFADDR */
 714                         if_up(ifp);
 715                 }
 716                 return (error);
 717
 718         case SIOCDIFADDR:
 719                 /*
 720                  * in_ifscrub kills the interface route.
 721                  */
 722                 in_ifscrub(ifp, ia);
 723                 /*
 724                  * in_ifadown gets rid of all the rest of
 725                  * the routes.  This is not quite the right
 726                  * thing to do, but at least if we are running
 727                  * a routing process they will come back.
 728                  */
 729                 in_ifadown(&ia->ia_ifa, 1);
 730                 EVENTHANDLER_INVOKE(ifaddr_event, ifp, IFADDR_EVENT_DELETE,
 731                                     &ia->ia_ifa);
 732                 error = 0;
 733                 break;
 734
 735         default:
 736                 if (ifp == NULL || ifp->if_ioctl == NULL)
 737                         return (EOPNOTSUPP);
 738                 ifnet_serialize_all(ifp);
 739                 error = ifp->if_ioctl(ifp, cmd, data, td->td_proc->p_ucred);
 740                 ifnet_deserialize_all(ifp);
 741                 return (error);
 742         }
 743
 744         KKASSERT(cmd == SIOCDIFADDR ||
 745                  ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) && iaIsNew));
 746
 747         ifa_ifunlink(&ia->ia_ifa, ifp);
 748         in_iaunlink(ia);
 749
 750         if (cmd == SIOCDIFADDR) {
 751                 ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 752                 if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
 753                         in_iahash_remove(ia);
 754         }
 755 #ifdef INVARIANTS
 756         else {
 757                 /*
 758                  * If cmd is SIOCSIFADDR or SIOCAIFADDR, in_ifinit() has
 759                  * already taken care of the deletion from hash table
 760                  */
 761                 ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 762                 KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
 763                         ("SIOC%cIFADDR failed on new ia, "
 764                          "but the new ia is still in hash table\n",
 765                          cmd == SIOCSIFADDR ? 'S' : 'A'));
 766         }
 767 #endif
 768
 769         ifa_destroy(&ia->ia_ifa);
 770
 771         if ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) &&
 772             !ifpWasUp && (ifp->if_flags & IFF_UP)) {
 773                 /*
 774                  * Though the address assignment failed, the
 775                  * interface is brought up by in_ifinit()
 776                  * (via ifp->if_ioctl).  With the hope that
 777                  * the interface has some valid addresses, we
 778                  * act as if IFF_UP flag was just set on the
 779                  * interface.
 780                  *
 781                  * NOTE:
 782                  * This could only be done after the failed
 783                  * address is unlinked from the global address
 784                  * list.
 785                  */
 786                 if_up(ifp);
 787         }
 788
 789         return (error);
 790 }
 791
 792 /*
 793  * SIOC[GAD]LIFADDR.
 794  *      SIOCGLIFADDR: get first address. (?!?)
 795  *      SIOCGLIFADDR with IFLR_PREFIX:
 796  *              get first address that matches the specified prefix.
 797  *      SIOCALIFADDR: add the specified address.
 798  *      SIOCALIFADDR with IFLR_PREFIX:
 799  *              EINVAL since we can't deduce hostid part of the address.
 800  *      SIOCDLIFADDR: delete the specified address.
 801  *      SIOCDLIFADDR with IFLR_PREFIX:
 802  *              delete the first address that matches the specified prefix.
 803  * return values:
 804  *      EINVAL on invalid parameters
 805  *      EADDRNOTAVAIL on prefix match failed/specified address not found
 806  *      other values may be returned from in_ioctl()
 807  *
 808  * NOTE! td might be NULL.
 809  */
 810 static int
 811 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
 812                  struct thread *td)
 813 {
 814         struct if_laddrreq *iflr = (struct if_laddrreq *)data;
 815
 816         /* sanity checks */
 817         if (!data || !ifp) {
 818                 panic("invalid argument to in_lifaddr_ioctl");
 819                 /*NOTRECHED*/
 820         }
 821
 822         switch (cmd) {
 823         case SIOCGLIFADDR:
 824                 /* address must be specified on GET with IFLR_PREFIX */
 825                 if ((iflr->flags & IFLR_PREFIX) == 0)
 826                         break;
 827                 /*FALLTHROUGH*/
 828         case SIOCALIFADDR:
 829         case SIOCDLIFADDR:
 830                 /* address must be specified on ADD and DELETE */
 831                 if (iflr->addr.ss_family != AF_INET)
 832                         return EINVAL;
 833                 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
 834                         return EINVAL;
 835                 /* XXX need improvement */
 836                 if (iflr->dstaddr.ss_family
 837                  && iflr->dstaddr.ss_family != AF_INET)
 838                         return EINVAL;
 839                 if (iflr->dstaddr.ss_family
 840                  && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
 841                         return EINVAL;
 842                 break;
 843         default: /*shouldn't happen*/
 844                 return EOPNOTSUPP;
 845         }
 846         if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
 847                 return EINVAL;
 848
 849         switch (cmd) {
 850         case SIOCALIFADDR:
 851             {
 852                 struct in_aliasreq ifra;
 853
 854                 if (iflr->flags & IFLR_PREFIX)
 855                         return EINVAL;
 856
 857                 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
 858                 bzero(&ifra, sizeof ifra);
 859                 bcopy(iflr->iflr_name, ifra.ifra_name, sizeof ifra.ifra_name);
 860
 861                 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
 862
 863                 if (iflr->dstaddr.ss_family) {  /*XXX*/
 864                         bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
 865                                 iflr->dstaddr.ss_len);
 866                 }
 867
 868                 ifra.ifra_mask.sin_family = AF_INET;
 869                 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
 870                 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
 871
 872                 return in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td);
 873             }
 874         case SIOCGLIFADDR:
 875         case SIOCDLIFADDR:
 876             {
 877                 struct ifaddr_container *ifac;
 878                 struct in_ifaddr *ia;
 879                 struct in_addr mask, candidate, match;
 880                 struct sockaddr_in *sin;
 881                 int cmp;
 882
 883                 bzero(&mask, sizeof mask);
 884                 if (iflr->flags & IFLR_PREFIX) {
 885                         /* lookup a prefix rather than address. */
 886                         in_len2mask(&mask, iflr->prefixlen);
 887
 888                         sin = (struct sockaddr_in *)&iflr->addr;
 889                         match.s_addr = sin->sin_addr.s_addr;
 890                         match.s_addr &= mask.s_addr;
 891
 892                         /* if you set extra bits, that's wrong */
 893                         if (match.s_addr != sin->sin_addr.s_addr)
 894                                 return EINVAL;
 895
 896                         cmp = 1;
 897                 } else {
 898                         if (cmd == SIOCGLIFADDR) {
 899                                 /* on getting an address, take the 1st match */
 900                                 match.s_addr = 0; /* gcc4 warning */
 901                                 cmp = 0;        /*XXX*/
 902                         } else {
 903                                 /* on deleting an address, do exact match */
 904                                 in_len2mask(&mask, 32);
 905                                 sin = (struct sockaddr_in *)&iflr->addr;
 906                                 match.s_addr = sin->sin_addr.s_addr;
 907
 908                                 cmp = 1;
 909                         }
 910                 }
 911
 912                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
 913                         struct ifaddr *ifa = ifac->ifa;
 914
 915                         if (ifa->ifa_addr->sa_family != AF_INET6)
 916                                 continue;
 917                         if (!cmp)
 918                                 break;
 919                         candidate.s_addr =
 920                         ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
 921                         candidate.s_addr &= mask.s_addr;
 922                         if (candidate.s_addr == match.s_addr)
 923                                 break;
 924                 }
 925                 if (ifac == NULL)
 926                         return EADDRNOTAVAIL;
 927                 ia = (struct in_ifaddr *)(ifac->ifa);
 928
 929                 if (cmd == SIOCGLIFADDR) {
 930                         /* fill in the if_laddrreq structure */
 931                         bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 932
 933                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 934                                 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
 935                                         ia->ia_dstaddr.sin_len);
 936                         } else
 937                                 bzero(&iflr->dstaddr, sizeof iflr->dstaddr);
 938
 939                         iflr->prefixlen =
 940                                 in_mask2len(&ia->ia_sockmask.sin_addr);
 941
 942                         iflr->flags = 0;        /*XXX*/
 943
 944                         return 0;
 945                 } else {
 946                         struct in_aliasreq ifra;
 947
 948                         /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
 949                         bzero(&ifra, sizeof ifra);
 950                         bcopy(iflr->iflr_name, ifra.ifra_name,
 951                                 sizeof ifra.ifra_name);
 952
 953                         bcopy(&ia->ia_addr, &ifra.ifra_addr,
 954                                 ia->ia_addr.sin_len);
 955                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 956                                 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
 957                                         ia->ia_dstaddr.sin_len);
 958                         }
 959                         bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
 960                                 ia->ia_sockmask.sin_len);
 961
 962                         return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
 963                                           ifp, td);
 964                 }
 965             }
 966         }
 967
 968         return EOPNOTSUPP;      /*just for safety*/
 969 }
 970
 971 /*
 972  * Delete any existing route for an interface.
 973  */
 974 void
 975 in_ifscrub(struct ifnet *ifp __unused, struct in_ifaddr *ia)
 976 {
 977         in_scrubprefix(ia);
 978 }
 979
 980 /*
 981  * Initialize an interface's internet address
 982  * and routing table entry.
 983  */
 984 static int
 985 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia,
 986           const struct sockaddr_in *sin, int scrub)
 987 {
 988         u_long i = ntohl(sin->sin_addr.s_addr);
 989         struct sockaddr_in oldaddr;
 990         struct ifaddr_container *ifac;
 991         int flags = RTF_UP, error = 0;
 992         int was_hash = 0;
 993
 994         ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 995         oldaddr = ia->ia_addr;
 996
 997         if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) {
 998                 was_hash = 1;
 999                 in_iahash_remove(ia);
1000         }
1001
1002         ia->ia_addr = *sin;
1003         if (ia->ia_addr.sin_family == AF_INET)
1004                 in_iahash_insert(ia);
1005
1006         /*
1007          * Give the interface a chance to initialize
1008          * if this is its first address,
1009          * and to validate the address if necessary.
1010          */
1011         if (ifp->if_ioctl != NULL) {
1012                 ifnet_serialize_all(ifp);
1013                 error = ifp->if_ioctl(ifp, SIOCSIFADDR, (caddr_t)ia, NULL);
1014                 ifnet_deserialize_all(ifp);
1015                 if (error)
1016                         goto fail;
1017         }
1018
1019         /*
1020          * Delete old route, if requested.
1021          */
1022         if (scrub) {
1023                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
1024                 in_ifscrub(ifp, ia);
1025                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
1026         }
1027
1028         /*
1029          * Calculate netmask/subnetmask.
1030          */
1031         if (IN_CLASSA(i))
1032                 ia->ia_netmask = IN_CLASSA_NET;
1033         else if (IN_CLASSB(i))
1034                 ia->ia_netmask = IN_CLASSB_NET;
1035         else
1036                 ia->ia_netmask = IN_CLASSC_NET;
1037         /*
1038          * The subnet mask usually includes at least the standard network part,
1039          * but may may be smaller in the case of supernetting.
1040          * If it is set, we believe it.
1041          */
1042         if (ia->ia_subnetmask == 0) {
1043                 ia->ia_subnetmask = ia->ia_netmask;
1044                 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
1045         } else {
1046                 ia->ia_netmask &= ia->ia_subnetmask;
1047         }
1048         ia->ia_net = i & ia->ia_netmask;
1049         ia->ia_subnet = i & ia->ia_subnetmask;
1050         in_socktrim(&ia->ia_sockmask);
1051
1052         /*
1053          * Add route for the network.
1054          */
1055         ia->ia_ifa.ifa_metric = ifp->if_metric;
1056         if (ifp->if_flags & IFF_BROADCAST) {
1057                 ia->ia_broadaddr.sin_addr.s_addr =
1058                         htonl(ia->ia_subnet | ~ia->ia_subnetmask);
1059                 ia->ia_netbroadcast.s_addr =
1060                         htonl(ia->ia_net | ~ ia->ia_netmask);
1061         } else if (ifp->if_flags & IFF_LOOPBACK) {
1062                 ia->ia_dstaddr = ia->ia_addr;
1063                 flags |= RTF_HOST;
1064         } else if (ifp->if_flags & IFF_POINTOPOINT) {
1065                 if (ia->ia_dstaddr.sin_family != AF_INET)
1066                         return (0);
1067                 flags |= RTF_HOST;
1068         }
1069
1070         /*-
1071          * Don't add host routes for interface addresses of
1072          * 0.0.0.0 --> 0.255.255.255 netmask 255.0.0.0.  This makes it
1073          * possible to assign several such address pairs with consistent
1074          * results (no host route) and is required by BOOTP.
1075          *
1076          * XXX: This is ugly !  There should be a way for the caller to
1077          *      say that they don't want a host route.
1078          */
1079         if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY ||
1080             ia->ia_netmask != IN_CLASSA_NET ||
1081             ia->ia_dstaddr.sin_addr.s_addr != htonl(IN_CLASSA_HOST)) {
1082                 error = in_addprefix(ia, flags);
1083                 if (error)
1084                         goto fail;
1085         }
1086
1087         /*
1088          * If the interface supports multicast, join the "all hosts"
1089          * multicast group on that interface.
1090          */
1091         if (ifp->if_flags & IFF_MULTICAST) {
1092                 struct in_addr addr;
1093
1094                 addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
1095                 in_addmulti(&addr, ifp);
1096         }
1097         return (0);
1098 fail:
1099         if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
1100                 in_iahash_remove(ia);
1101
1102         ia->ia_addr = oldaddr;
1103         if (was_hash)
1104                 in_iahash_insert(ia);
1105         return (error);
1106 }
1107
1108 #define rtinitflags(x) \
1109         (((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) \
1110          ? RTF_HOST : 0)
1111
1112 /*
1113  * Add a route to prefix ("connected route" in cisco terminology).
1114  * Do nothing, if there are some interface addresses with the same
1115  * prefix already.  This function assumes that the 'target' parent
1116  * interface is UP.
1117  */
1118 static int
1119 in_addprefix(struct in_ifaddr *target, int flags)
1120 {
1121         struct in_ifaddr_container *iac;
1122         struct in_addr prefix, mask;
1123         int error;
1124
1125         mask = target->ia_sockmask.sin_addr;
1126         if (flags & RTF_HOST) {
1127                 prefix = target->ia_dstaddr.sin_addr;
1128         } else {
1129                 prefix = target->ia_addr.sin_addr;
1130                 prefix.s_addr &= mask.s_addr;
1131         }
1132
1133         TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1134                 struct in_ifaddr *ia = iac->ia;
1135                 struct in_addr p;
1136
1137                 /* Don't test against self */
1138                 if (ia == target)
1139                         continue;
1140
1141                 /* The tested address does not own a route entry */
1142                 if ((ia->ia_flags & IFA_ROUTE) == 0)
1143                         continue;
1144
1145                 /* Prefix test */
1146                 if (rtinitflags(ia)) {
1147                         p = ia->ia_dstaddr.sin_addr;
1148                 } else {
1149                         p = ia->ia_addr.sin_addr;
1150                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1151                 }
1152                 if (prefix.s_addr != p.s_addr)
1153                         continue;
1154
1155                 /*
1156                  * If the to-be-added address and the curretly being
1157                  * tested address are not host addresses, we need to
1158                  * take subnetmask into consideration.
1159                  */
1160                 if (!(flags & RTF_HOST) && !rtinitflags(ia) &&
1161                     mask.s_addr != ia->ia_sockmask.sin_addr.s_addr)
1162                         continue;
1163
1164                 /*
1165                  * If we got a matching prefix route inserted by other
1166                  * interface address, we don't need to bother.
1167                  */
1168                 return 0;
1169         }
1170
1171         /*
1172          * No one seem to have prefix route; insert it.
1173          */
1174         error = rtinit(&target->ia_ifa, RTM_ADD, flags);
1175         if (!error)
1176                 target->ia_flags |= IFA_ROUTE;
1177         return error;
1178 }
1179
1180 /*
1181  * Remove a route to prefix ("connected route" in cisco terminology).
1182  * Re-installs the route by using another interface address, if there's
1183  * one with the same prefix (otherwise we lose the route mistakenly).
1184  */
1185 static void
1186 in_scrubprefix(struct in_ifaddr *target)
1187 {
1188         struct in_ifaddr_container *iac;
1189         struct in_addr prefix, mask;
1190         int error;
1191
1192         if ((target->ia_flags & IFA_ROUTE) == 0)
1193                 return;
1194
1195         mask = target->ia_sockmask.sin_addr;
1196         if (rtinitflags(target)) {
1197                 prefix = target->ia_dstaddr.sin_addr;
1198         } else {
1199                 prefix = target->ia_addr.sin_addr;
1200                 prefix.s_addr &= mask.s_addr;
1201         }
1202
1203         TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1204                 struct in_ifaddr *ia = iac->ia;
1205                 struct in_addr p;
1206
1207                 /* Don't test against self */
1208                 if (ia == target)
1209                         continue;
1210
1211                 /* The tested address already owns a route entry */
1212                 if (ia->ia_flags & IFA_ROUTE)
1213                         continue;
1214
1215                 /*
1216                  * The prefix route of the tested address should
1217                  * never be installed if its parent interface is
1218                  * not UP yet.
1219                  */
1220                 if ((ia->ia_ifp->if_flags & IFF_UP) == 0)
1221                         continue;
1222
1223                 /* Prefix test */
1224                 if (rtinitflags(ia)) {
1225                         p = ia->ia_dstaddr.sin_addr;
1226                 } else {
1227                         p = ia->ia_addr.sin_addr;
1228                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1229                 }
1230                 if (prefix.s_addr != p.s_addr)
1231                         continue;
1232
1233                 /*
1234                  * We don't need to test subnetmask here, as what we do
1235                  * in in_addprefix(), since if the the tested address's
1236                  * parent interface is UP, the tested address should own
1237                  * a prefix route entry and we would never reach here.
1238                  */
1239
1240                 /*
1241                  * If we got a matching prefix route, move IFA_ROUTE to him
1242                  */
1243                 rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1244                 target->ia_flags &= ~IFA_ROUTE;
1245
1246                 error = rtinit(&ia->ia_ifa, RTM_ADD, rtinitflags(ia) | RTF_UP);
1247                 if (!error)
1248                         ia->ia_flags |= IFA_ROUTE;
1249                 return;
1250         }
1251
1252         /*
1253          * No candidates for this prefix route; just remove it.
1254          */
1255         rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1256         target->ia_flags &= ~IFA_ROUTE;
1257 }
1258
1259 #undef rtinitflags
1260
1261 /*
1262  * Return 1 if the address might be a local broadcast address.
1263  */
1264 int
1265 in_broadcast(struct in_addr in, struct ifnet *ifp)
1266 {
1267         struct ifaddr_container *ifac;
1268         u_long t;
1269
1270         if (in.s_addr == INADDR_BROADCAST ||
1271             in.s_addr == INADDR_ANY)
1272                 return 1;
1273         if ((ifp->if_flags & IFF_BROADCAST) == 0)
1274                 return 0;
1275         t = ntohl(in.s_addr);
1276         /*
1277          * Look through the list of addresses for a match
1278          * with a broadcast address.
1279          */
1280 #define ia ((struct in_ifaddr *)ifa)
1281         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1282                 struct ifaddr *ifa = ifac->ifa;
1283
1284                 if (ifa->ifa_addr->sa_family == AF_INET &&
1285                     (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1286                      in.s_addr == ia->ia_netbroadcast.s_addr ||
1287                      /*
1288                       * Check for old-style (host 0) broadcast.
1289                       */
1290                      t == ia->ia_subnet || t == ia->ia_net) &&
1291                      /*
1292                       * Check for an all one subnetmask. These
1293                       * only exist when an interface gets a secondary
1294                       * address.
1295                       */
1296                      ia->ia_subnetmask != (u_long)0xffffffff)
1297                             return 1;
1298         }
1299         return (0);
1300 #undef ia
1301 }
1302 /*
1303  * Add an address to the list of IP multicast addresses for a given interface.
1304  */
1305 struct in_multi *
1306 in_addmulti(struct in_addr *ap, struct ifnet *ifp)
1307 {
1308         struct in_multi *inm;
1309         int error;
1310         struct sockaddr_in sin;
1311         struct ifmultiaddr *ifma;
1312
1313         /*
1314          * Call generic routine to add membership or increment
1315          * refcount.  It wants addresses in the form of a sockaddr,
1316          * so we build one here (being careful to zero the unused bytes).
1317          */
1318         bzero(&sin, sizeof sin);
1319         sin.sin_family = AF_INET;
1320         sin.sin_len = sizeof sin;
1321         sin.sin_addr = *ap;
1322         crit_enter();
1323         error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
1324         if (error) {
1325                 crit_exit();
1326                 return 0;
1327         }
1328
1329         /*
1330          * If ifma->ifma_protospec is null, then if_addmulti() created
1331          * a new record.  Otherwise, we are done.
1332          */
1333         if (ifma->ifma_protospec != 0) {
1334                 crit_exit();
1335                 return ifma->ifma_protospec;
1336         }
1337
1338         /* XXX - if_addmulti uses M_WAITOK.  Can this really be called
1339            at interrupt time?  If so, need to fix if_addmulti. XXX */
1340         inm = kmalloc(sizeof *inm, M_IPMADDR, M_WAITOK | M_ZERO);
1341         inm->inm_addr = *ap;
1342         inm->inm_ifp = ifp;
1343         inm->inm_ifma = ifma;
1344         ifma->ifma_protospec = inm;
1345         LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
1346
1347         /*
1348          * Let IGMP know that we have joined a new IP multicast group.
1349          */
1350         igmp_joingroup(inm);
1351         crit_exit();
1352         return (inm);
1353 }
1354
1355 /*
1356  * Delete a multicast address record.
1357  */
1358 void
1359 in_delmulti(struct in_multi *inm)
1360 {
1361         struct ifmultiaddr *ifma;
1362         struct in_multi my_inm;
1363
1364         crit_enter();
1365         ifma = inm->inm_ifma;
1366         my_inm.inm_ifp = NULL ; /* don't send the leave msg */
1367         if (ifma->ifma_refcount == 1) {
1368                 /*
1369                  * No remaining claims to this record; let IGMP know that
1370                  * we are leaving the multicast group.
1371                  * But do it after the if_delmulti() which might reset
1372                  * the interface and nuke the packet.
1373                  */
1374                 my_inm = *inm ;
1375                 ifma->ifma_protospec = 0;
1376                 LIST_REMOVE(inm, inm_link);
1377                 kfree(inm, M_IPMADDR);
1378         }
1379         /* XXX - should be separate API for when we have an ifma? */
1380         if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
1381         if (my_inm.inm_ifp != NULL)
1382                 igmp_leavegroup(&my_inm);
1383         crit_exit();
1384 }
1385
1386 void
1387 in_ifdetach(struct ifnet *ifp)
1388 {
1389         in_pcbpurgeif0(LIST_FIRST(&ripcbinfo.pcblisthead), ifp);
1390         in_pcbpurgeif0(LIST_FIRST(&udbinfo.pcblisthead), ifp);
1391 }