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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)in.c        8.4 (Berkeley) 1/9/95
  30  * $FreeBSD: src/sys/netinet/in.c,v 1.44.2.14 2002/11/08 00:45:50 suz Exp $
  31  */
  32
  33 #include "opt_bootp.h"
  34 #include "opt_carp.h"
  35
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/sockio.h>
  39 #include <sys/malloc.h>
  40 #include <sys/proc.h>
  41 #include <sys/caps.h>
  42 #include <sys/msgport.h>
  43 #include <sys/socket.h>
  44
  45 #include <sys/kernel.h>
  46 #include <sys/sysctl.h>
  47 #include <sys/thread2.h>
  48
  49 #include <net/if.h>
  50 #include <net/if_types.h>
  51 #include <net/route.h>
  52 #include <net/netmsg2.h>
  53 #include <net/netisr2.h>
  54
  55 #include <netinet/in.h>
  56 #include <netinet/in_var.h>
  57 #include <netinet/in_pcb.h>
  58 #include <netinet/udp_var.h>
  59
  60 #include <netinet/igmp_var.h>
  61
  62 MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address");
  63
  64 static int in_mask2len (struct in_addr *);
  65 static void in_len2mask (struct in_addr *, int);
  66 static int in_lifaddr_ioctl (u_long, caddr_t, struct ifnet *, struct thread *);
  67
  68 static void     in_socktrim (struct sockaddr_in *);
  69 static int      in_ifinit(struct ifnet *, struct in_ifaddr *,
  70                     const struct sockaddr_in *, int);
  71
  72 static int      in_control_internal(u_long, caddr_t, struct ifnet *,
  73                     struct thread *);
  74
  75 static int      in_addprefix(struct in_ifaddr *, int);
  76 static void     in_scrubprefix(struct in_ifaddr *);
  77
  78 static int subnetsarelocal = 0;
  79 SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
  80     &subnetsarelocal, 0,
  81     "Count all internet addresses of subnets of the local net as local");
  82
  83 struct in_multihead in_multihead; /* XXX BSS initialization */
  84
  85 extern struct inpcbinfo ripcbinfo;
  86
  87 /*
  88  * Return 1 if an internet address is for a ``local'' host
  89  * (one to which we have a connection).  If subnetsarelocal
  90  * is true, this includes other subnets of the local net.
  91  * Otherwise, it includes only the directly-connected (sub)nets.
  92  */
  93 int
  94 in_localaddr(struct in_addr in)
  95 {
  96         u_long i = ntohl(in.s_addr);
  97         struct in_ifaddr_container *iac;
  98         struct in_ifaddr *ia;
  99
 100         if (subnetsarelocal) {
 101                 TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
 102                         ia = iac->ia;
 103                         if ((i & ia->ia_netmask) == ia->ia_net)
 104                                 return (1);
 105                 }
 106         } else {
 107                 TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
 108                         ia = iac->ia;
 109                         if ((i & ia->ia_subnetmask) == ia->ia_subnet)
 110                                 return (1);
 111                 }
 112         }
 113
 114         return (0);
 115 }
 116
 117 /*
 118  * Determine whether an IP address is in a reserved set of addresses
 119  * that may not be forwarded, or whether datagrams to that destination
 120  * may be forwarded.
 121  */
 122 int
 123 in_canforward(struct in_addr in)
 124 {
 125         u_long i = ntohl(in.s_addr);
 126         u_long net;
 127
 128         if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
 129                 return (0);
 130         if (IN_CLASSA(i)) {
 131                 net = i & IN_CLASSA_NET;
 132                 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
 133                         return (0);
 134         }
 135         return (1);
 136 }
 137
 138 /*
 139  * Trim a mask in a sockaddr
 140  */
 141 static void
 142 in_socktrim(struct sockaddr_in *ap)
 143 {
 144         char *cplim = (char *) &ap->sin_addr;
 145         char *cp = (char *) (&ap->sin_addr + 1);
 146
 147         ap->sin_len = 0;
 148         while (--cp >= cplim) {
 149                 if (*cp) {
 150                         (ap)->sin_len = cp - (char *) (ap) + 1;
 151                         break;
 152                 }
 153         }
 154 }
 155
 156 static int
 157 in_mask2len(struct in_addr *mask)
 158 {
 159         int x, y;
 160         u_char *p;
 161
 162         p = (u_char *)mask;
 163         for (x = 0; x < sizeof *mask; x++) {
 164                 if (p[x] != 0xff)
 165                         break;
 166         }
 167         y = 0;
 168         if (x < sizeof *mask) {
 169                 for (y = 0; y < 8; y++) {
 170                         if ((p[x] & (0x80 >> y)) == 0)
 171                                 break;
 172                 }
 173         }
 174         return x * 8 + y;
 175 }
 176
 177 static void
 178 in_len2mask(struct in_addr *mask, int len)
 179 {
 180         int i;
 181         u_char *p;
 182
 183         p = (u_char *)mask;
 184         bzero(mask, sizeof *mask);
 185         for (i = 0; i < len / 8; i++)
 186                 p[i] = 0xff;
 187         if (len % 8)
 188                 p[i] = (0xff00 >> (len % 8)) & 0xff;
 189 }
 190
 191 void
 192 in_control_dispatch(netmsg_t msg)
 193 {
 194         int error;
 195
 196         error = in_control(msg->control.nm_cmd, msg->control.nm_data,
 197                            msg->control.nm_ifp, msg->control.nm_td);
 198         lwkt_replymsg(&msg->lmsg, error);
 199 }
 200
 201 static void
 202 in_control_internal_dispatch(netmsg_t msg)
 203 {
 204         int error;
 205
 206         error = in_control_internal(msg->control.nm_cmd,
 207                                     msg->control.nm_data,
 208                                     msg->control.nm_ifp,
 209                                     msg->control.nm_td);
 210         lwkt_replymsg(&msg->lmsg, error);
 211 }
 212
 213 /*
 214  * Generic internet control operations (ioctl's).
 215  * Ifp is 0 if not an interface-specific ioctl.
 216  *
 217  * NOTE! td might be NULL.
 218  */
 219 int
 220 in_control(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td)
 221 {
 222         struct netmsg_pru_control msg;
 223
 224         switch (cmd) {
 225         /* change address */
 226         case SIOCALIFADDR:
 227         case SIOCDLIFADDR:
 228         case SIOCSIFDSTADDR:
 229         case SIOCSIFBRDADDR:
 230         case SIOCSIFADDR:
 231         case SIOCSIFNETMASK:
 232         case SIOCAIFADDR:
 233         case SIOCDIFADDR:
 234         case SIOCGIFALIAS:
 235                 /*
 236                  * Dispatch these SIOCs to netisr0.
 237                  */
 238                 netmsg_init(&msg.base, NULL, &curthread->td_msgport, 0,
 239                             in_control_internal_dispatch);
 240                 msg.nm_cmd = cmd;
 241                 msg.nm_data = data;
 242                 msg.nm_ifp = ifp;
 243                 msg.nm_td = td;
 244                 lwkt_domsg(netisr_cpuport(0), &msg.base.lmsg, 0);
 245                 return msg.base.lmsg.ms_error;
 246
 247         default:
 248                 return in_control_internal(cmd, data, ifp, td);
 249         }
 250 }
 251
 252 static void
 253 in_ialink_dispatch(netmsg_t msg)
 254 {
 255         struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
 256         struct ifaddr_container *ifac;
 257         struct in_ifaddr_container *iac;
 258         int cpu = mycpuid;
 259
 260         crit_enter();
 261
 262         ifac = &ia->ia_ifa.ifa_containers[cpu];
 263         ASSERT_IFAC_VALID(ifac);
 264         KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD) == 0,
 265                 ("ia is on in_ifaddrheads"));
 266
 267         ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHEAD;
 268         iac = &ifac->ifa_proto_u.u_in_ifac;
 269         TAILQ_INSERT_TAIL(&in_ifaddrheads[cpu], iac, ia_link);
 270
 271         crit_exit();
 272
 273         netisr_forwardmsg_all(&msg->base, cpu + 1);
 274 }
 275
 276 static void
 277 in_iaunlink_dispatch(netmsg_t msg)
 278 {
 279         struct in_ifaddr *ia = msg->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,
 289                 ("ia is not on in_ifaddrheads"));
 290
 291         iac = &ifac->ifa_proto_u.u_in_ifac;
 292         TAILQ_REMOVE(&in_ifaddrheads[cpu], iac, ia_link);
 293         ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHEAD;
 294
 295         crit_exit();
 296
 297         netisr_forwardmsg_all(&msg->base, cpu + 1);
 298 }
 299
 300 static void
 301 in_iahashins_dispatch(netmsg_t msg)
 302 {
 303         struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
 304         struct ifaddr_container *ifac;
 305         struct in_ifaddr_container *iac;
 306         int cpu = mycpuid;
 307
 308         crit_enter();
 309
 310         ifac = &ia->ia_ifa.ifa_containers[cpu];
 311         ASSERT_IFAC_VALID(ifac);
 312         KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
 313                 ("ia is on in_ifaddrhashtbls"));
 314
 315         ifac->ifa_listmask |= IFA_LIST_IN_IFADDRHASH;
 316         iac = &ifac->ifa_proto_u.u_in_ifac;
 317         LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
 318                          iac, ia_hash);
 319
 320         crit_exit();
 321
 322         netisr_forwardmsg_all(&msg->base, cpu + 1);
 323 }
 324
 325 static void
 326 in_iahashrem_dispatch(netmsg_t msg)
 327 {
 328         struct in_ifaddr *ia = msg->lmsg.u.ms_resultp;
 329         struct ifaddr_container *ifac;
 330         struct in_ifaddr_container *iac;
 331         int cpu = mycpuid;
 332
 333         crit_enter();
 334
 335         ifac = &ia->ia_ifa.ifa_containers[cpu];
 336         ASSERT_IFAC_VALID(ifac);
 337         KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH,
 338                 ("ia is not on in_ifaddrhashtbls"));
 339
 340         iac = &ifac->ifa_proto_u.u_in_ifac;
 341         LIST_REMOVE(iac, ia_hash);
 342         ifac->ifa_listmask &= ~IFA_LIST_IN_IFADDRHASH;
 343
 344         crit_exit();
 345
 346         netisr_forwardmsg_all(&msg->base, cpu + 1);
 347 }
 348
 349 static void
 350 in_ialink(struct in_ifaddr *ia)
 351 {
 352         struct netmsg_base msg;
 353
 354         netmsg_init(&msg, NULL, &curthread->td_msgport,
 355                     0, in_ialink_dispatch);
 356         msg.lmsg.u.ms_resultp = ia;
 357
 358         netisr_domsg(&msg, 0);
 359 }
 360
 361 void
 362 in_iaunlink(struct in_ifaddr *ia)
 363 {
 364         struct netmsg_base msg;
 365
 366         netmsg_init(&msg, NULL, &curthread->td_msgport,
 367                     0, in_iaunlink_dispatch);
 368         msg.lmsg.u.ms_resultp = ia;
 369
 370         netisr_domsg(&msg, 0);
 371 }
 372
 373 void
 374 in_iahash_insert(struct in_ifaddr *ia)
 375 {
 376         struct netmsg_base msg;
 377
 378         netmsg_init(&msg, NULL, &curthread->td_msgport,
 379                     0, in_iahashins_dispatch);
 380         msg.lmsg.u.ms_resultp = ia;
 381
 382         netisr_domsg(&msg, 0);
 383 }
 384
 385 void
 386 in_iahash_remove(struct in_ifaddr *ia)
 387 {
 388         struct netmsg_base msg;
 389
 390         netmsg_init(&msg, NULL, &curthread->td_msgport,
 391                     0, in_iahashrem_dispatch);
 392         msg.lmsg.u.ms_resultp = ia;
 393
 394         netisr_domsg(&msg, 0);
 395 }
 396
 397 static __inline struct in_ifaddr *
 398 in_ianext(struct in_ifaddr *oia)
 399 {
 400         struct ifaddr_container *ifac;
 401         struct in_ifaddr_container *iac;
 402
 403         ifac = &oia->ia_ifa.ifa_containers[mycpuid];
 404         ASSERT_IFAC_VALID(ifac);
 405         KASSERT(ifac->ifa_listmask & IFA_LIST_IN_IFADDRHEAD,
 406                 ("ia is not on in_ifaddrheads"));
 407
 408         iac = &ifac->ifa_proto_u.u_in_ifac;
 409         iac = TAILQ_NEXT(iac, ia_link);
 410         if (iac != NULL)
 411                 return iac->ia;
 412         else
 413                 return NULL;
 414 }
 415
 416 static int
 417 in_control_internal(u_long cmd, caddr_t data, struct ifnet *ifp,
 418                     struct thread *td)
 419 {
 420         struct ifreq *ifr = (struct ifreq *)data;
 421         struct in_ifaddr *ia = NULL;
 422         struct in_addr dst;
 423         struct in_aliasreq *ifra = (struct in_aliasreq *)data;
 424         struct ifaddr_container *ifac;
 425         struct in_ifaddr_container *iac;
 426         struct sockaddr_in oldaddr;
 427         int hostIsNew, iaIsNew, maskIsNew, ifpWasUp;
 428         int error = 0;
 429
 430         switch (cmd) {
 431         case SIOCALIFADDR:
 432         case SIOCDLIFADDR:
 433                 if (td && (error = caps_priv_check_td(td,
 434                                                 SYSCAP_RESTRICTEDROOT)) != 0)
 435                 {
 436                         return error;
 437                 }
 438                 /* FALLTHROUGH */
 439         case SIOCGLIFADDR:
 440                 if (!ifp)
 441                         return EINVAL;
 442                 return in_lifaddr_ioctl(cmd, data, ifp, td);
 443         }
 444
 445         iaIsNew = 0;
 446         ifpWasUp = 0;
 447
 448         /*
 449          * Find address for this interface, if it exists.
 450          *
 451          * If an alias address was specified, find that one instead of
 452          * the first one on the interface, if possible.
 453          */
 454         if (ifp) {
 455                 struct in_ifaddr *iap;
 456
 457                 dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
 458                 LIST_FOREACH(iac, INADDR_HASH(dst.s_addr), ia_hash) {
 459                         iap = iac->ia;
 460                         if (iap->ia_ifp == ifp &&
 461                             iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
 462                                 ia = iap;
 463                                 break;
 464                         }
 465                 }
 466                 if (ia == NULL) {
 467                         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid],
 468                                       ifa_link) {
 469                                 iap = ifatoia(ifac->ifa);
 470                                 if (iap->ia_addr.sin_family == AF_INET) {
 471                                         ia = iap;
 472                                         break;
 473                                 }
 474                         }
 475                 }
 476
 477                 if (ifp->if_flags & IFF_UP)
 478                         ifpWasUp = 1;
 479         }
 480
 481         switch (cmd) {
 482         case SIOCAIFADDR:
 483         case SIOCDIFADDR:
 484         case SIOCGIFALIAS:
 485                 if (ifp == NULL)
 486                         return (EADDRNOTAVAIL);
 487                 if (ifra->ifra_addr.sin_family == AF_INET) {
 488                         while (ia != NULL) {
 489                                 if (ia->ia_ifp == ifp  &&
 490                                     ia->ia_addr.sin_addr.s_addr ==
 491                                     ifra->ifra_addr.sin_addr.s_addr)
 492                                         break;
 493                                 ia = in_ianext(ia);
 494                         }
 495                         if ((ifp->if_flags & IFF_POINTOPOINT) &&
 496                             cmd == SIOCAIFADDR &&
 497                             ifra->ifra_dstaddr.sin_addr.s_addr == INADDR_ANY) {
 498                                 return EDESTADDRREQ;
 499                         }
 500                 }
 501                 if ((cmd == SIOCDIFADDR || cmd == SIOCGIFALIAS) && ia == NULL)
 502                         return (EADDRNOTAVAIL);
 503                 if (cmd == SIOCGIFALIAS)
 504                         break;
 505                 /* FALLTHROUGH */
 506         case SIOCSIFADDR:
 507         case SIOCSIFNETMASK:
 508         case SIOCSIFDSTADDR:
 509                 if (td && (error = caps_priv_check_td(td,
 510                                                 SYSCAP_RESTRICTEDROOT)) != 0)
 511                 {
 512                         return error;
 513                 }
 514
 515                 if (ifp == NULL)
 516                         return (EADDRNOTAVAIL);
 517
 518                 if (cmd == SIOCSIFDSTADDR &&
 519                     (ifp->if_flags & IFF_POINTOPOINT) == 0)
 520                         return (EINVAL);
 521
 522                 if (ia == NULL) {
 523                         struct ifaddr *ifa;
 524                         int i;
 525
 526                         ia = ifa_create(sizeof(*ia));
 527                         ifa = &ia->ia_ifa;
 528
 529                         /*
 530                          * Setup per-CPU information
 531                          */
 532                         for (i = 0; i < ncpus; ++i) {
 533                                 ifac = &ifa->ifa_containers[i];
 534                                 iac = &ifac->ifa_proto_u.u_in_ifac;
 535                                 iac->ia = ia;
 536                                 iac->ia_ifac = ifac;
 537                         }
 538
 539                         ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 540                         ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 541                         ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 542                         ia->ia_sockmask.sin_len = 8;
 543                         ia->ia_sockmask.sin_family = AF_INET;
 544                         if (ifp->if_flags & IFF_BROADCAST) {
 545                                 ia->ia_broadaddr.sin_len = sizeof ia->ia_addr;
 546                                 ia->ia_broadaddr.sin_family = AF_INET;
 547                         }
 548                         ia->ia_ifp = ifp;
 549                         iaIsNew = 1;
 550
 551                         in_ialink(ia);
 552                         ifa_iflink(ifa, ifp, 1);
 553                 }
 554                 break;
 555
 556         case SIOCSIFBRDADDR:
 557                 if (td && (error = caps_priv_check_td(td,
 558                                                 SYSCAP_RESTRICTEDROOT)) != 0)
 559                 {
 560                         return error;
 561                 }
 562                 /* FALLTHROUGH */
 563
 564         case SIOCGIFADDR:
 565         case SIOCGIFNETMASK:
 566         case SIOCGIFDSTADDR:
 567         case SIOCGIFBRDADDR:
 568                 if (ia == NULL)
 569                         return (EADDRNOTAVAIL);
 570                 break;
 571         }
 572
 573         switch (cmd) {
 574         case SIOCGIFADDR:
 575                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
 576                 return (0);
 577
 578         case SIOCGIFBRDADDR:
 579                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 580                         return (EINVAL);
 581                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
 582                 return (0);
 583
 584         case SIOCGIFDSTADDR:
 585                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 586                         return (EINVAL);
 587                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
 588                 return (0);
 589
 590         case SIOCGIFNETMASK:
 591                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
 592                 return (0);
 593
 594         case SIOCSIFDSTADDR:
 595                 KKASSERT(ifp->if_flags & IFF_POINTOPOINT);
 596
 597                 oldaddr = ia->ia_dstaddr;
 598                 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
 599                 if (ifp->if_ioctl != NULL) {
 600                         ifnet_serialize_all(ifp);
 601                         error = ifp->if_ioctl(ifp, SIOCSIFDSTADDR, (caddr_t)ia,
 602                                               td->td_proc->p_ucred);
 603                         ifnet_deserialize_all(ifp);
 604                         if (error) {
 605                                 ia->ia_dstaddr = oldaddr;
 606                                 return (error);
 607                         }
 608                 }
 609                 if (ia->ia_flags & IFA_ROUTE) {
 610                         ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
 611                         rtinit(&ia->ia_ifa, RTM_DELETE, RTF_HOST);
 612                         ia->ia_ifa.ifa_dstaddr =
 613                                         (struct sockaddr *)&ia->ia_dstaddr;
 614                         rtinit(&ia->ia_ifa, RTM_ADD, RTF_HOST | RTF_UP);
 615                 }
 616                 return (0);
 617
 618         case SIOCSIFBRDADDR:
 619                 if ((ifp->if_flags & IFF_BROADCAST) == 0)
 620                         return (EINVAL);
 621                 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 622                 return (0);
 623
 624         case SIOCSIFADDR:
 625                 error = in_ifinit(ifp, ia,
 626                     (const struct sockaddr_in *)&ifr->ifr_addr, 1);
 627                 if (error != 0 && iaIsNew)
 628                         break;
 629                 if (error == 0) {
 630                         EVENTHANDLER_INVOKE(ifaddr_event, ifp,
 631                         iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
 632                         &ia->ia_ifa);
 633                 }
 634                 if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
 635                         /*
 636                          * Interface is brought up by in_ifinit()
 637                          * (via ifp->if_ioctl).  We act as if the
 638                          * interface got IFF_UP flag turned on.
 639                          */
 640                         if_up(ifp);
 641                 }
 642                 return (0);
 643
 644         case SIOCSIFNETMASK:
 645                 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
 646                 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
 647                 return (0);
 648
 649         case SIOCAIFADDR:
 650                 maskIsNew = 0;
 651                 hostIsNew = 1;
 652                 error = 0;
 653                 if (ia->ia_addr.sin_family == AF_INET) {
 654                         if (ifra->ifra_addr.sin_len == 0) {
 655                                 ifra->ifra_addr = ia->ia_addr;
 656                                 hostIsNew = 0;
 657                         } else if (ifra->ifra_addr.sin_addr.s_addr ==
 658                                    ia->ia_addr.sin_addr.s_addr) {
 659                                 hostIsNew = 0;
 660                         }
 661                 }
 662                 if (ifra->ifra_mask.sin_len) {
 663                         in_ifscrub(ifp, ia);
 664                         ia->ia_sockmask = ifra->ifra_mask;
 665                         ia->ia_sockmask.sin_family = AF_INET;
 666                         ia->ia_subnetmask =
 667                             ntohl(ia->ia_sockmask.sin_addr.s_addr);
 668                         maskIsNew = 1;
 669                 }
 670                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 671                     ifra->ifra_dstaddr.sin_family == AF_INET) {
 672                         in_ifscrub(ifp, ia);
 673                         ia->ia_dstaddr = ifra->ifra_dstaddr;
 674                         maskIsNew  = 1; /* We lie; but the effect's the same */
 675                 }
 676                 if (ifra->ifra_addr.sin_family == AF_INET &&
 677                     (hostIsNew || maskIsNew))
 678                         error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
 679
 680                 if (error != 0 && iaIsNew)
 681                         break;
 682
 683                 if ((ifp->if_flags & IFF_BROADCAST) &&
 684                     ifra->ifra_broadaddr.sin_family == AF_INET)
 685                         ia->ia_broadaddr = ifra->ifra_broadaddr;
 686                 if (error == 0) {
 687                         EVENTHANDLER_INVOKE(ifaddr_event, ifp,
 688                         iaIsNew ? IFADDR_EVENT_ADD : IFADDR_EVENT_CHANGE,
 689                         &ia->ia_ifa);
 690                 }
 691                 if (!ifpWasUp && (ifp->if_flags & IFF_UP)) {
 692                         /* See the comment in SIOCSIFADDR */
 693                         if_up(ifp);
 694                 }
 695                 return (error);
 696
 697         case SIOCGIFALIAS:
 698                 ifra->ifra_mask = ia->ia_sockmask;
 699                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 700                     (ia->ia_dstaddr.sin_family == AF_INET))
 701                         ifra->ifra_dstaddr = ia->ia_dstaddr;
 702                 else if ((ifp->if_flags & IFF_BROADCAST) &&
 703                     (ia->ia_broadaddr.sin_family == AF_INET))
 704                         ifra->ifra_broadaddr = ia->ia_broadaddr;
 705                 else
 706                         memset(&ifra->ifra_broadaddr, 0,
 707                             sizeof(ifra->ifra_broadaddr));
 708                 return (0);
 709
 710         case SIOCDIFADDR:
 711                 /*
 712                  * in_ifscrub kills the interface route.
 713                  */
 714                 in_ifscrub(ifp, ia);
 715                 /*
 716                  * in_ifadown gets rid of all the rest of
 717                  * the routes.  This is not quite the right
 718                  * thing to do, but at least if we are running
 719                  * a routing process they will come back.
 720                  */
 721                 in_ifadown(&ia->ia_ifa, 1);
 722                 EVENTHANDLER_INVOKE(ifaddr_event, ifp, IFADDR_EVENT_DELETE,
 723                                     &ia->ia_ifa);
 724                 error = 0;
 725                 break;
 726
 727         default:
 728                 if (ifp == NULL || ifp->if_ioctl == NULL)
 729                         return (EOPNOTSUPP);
 730                 ifnet_serialize_all(ifp);
 731                 error = ifp->if_ioctl(ifp, cmd, data, td->td_proc->p_ucred);
 732                 ifnet_deserialize_all(ifp);
 733                 return (error);
 734         }
 735
 736         KKASSERT(cmd == SIOCDIFADDR ||
 737                  ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) && iaIsNew));
 738
 739         ifa_ifunlink(&ia->ia_ifa, ifp);
 740         in_iaunlink(ia);
 741
 742         if (cmd == SIOCDIFADDR) {
 743                 ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 744                 if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
 745                         in_iahash_remove(ia);
 746         }
 747 #ifdef INVARIANTS
 748         else {
 749                 /*
 750                  * If cmd is SIOCSIFADDR or SIOCAIFADDR, in_ifinit() has
 751                  * already taken care of the deletion from hash table
 752                  */
 753                 ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 754                 KASSERT((ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) == 0,
 755                         ("SIOC%cIFADDR failed on new ia, "
 756                          "but the new ia is still in hash table",
 757                          cmd == SIOCSIFADDR ? 'S' : 'A'));
 758         }
 759 #endif
 760
 761         ifa_destroy(&ia->ia_ifa);
 762
 763         if ((cmd == SIOCAIFADDR || cmd == SIOCSIFADDR) &&
 764             !ifpWasUp && (ifp->if_flags & IFF_UP)) {
 765                 /*
 766                  * Though the address assignment failed, the
 767                  * interface is brought up by in_ifinit()
 768                  * (via ifp->if_ioctl).  With the hope that
 769                  * the interface has some valid addresses, we
 770                  * act as if IFF_UP flag was just set on the
 771                  * interface.
 772                  *
 773                  * NOTE:
 774                  * This could only be done after the failed
 775                  * address is unlinked from the global address
 776                  * list.
 777                  */
 778                 if_up(ifp);
 779         }
 780
 781         return (error);
 782 }
 783
 784 /*
 785  * SIOC[GAD]LIFADDR.
 786  *      SIOCGLIFADDR: get first address. (?!?)
 787  *      SIOCGLIFADDR with IFLR_PREFIX:
 788  *              get first address that matches the specified prefix.
 789  *      SIOCALIFADDR: add the specified address.
 790  *      SIOCALIFADDR with IFLR_PREFIX:
 791  *              EINVAL since we can't deduce hostid part of the address.
 792  *      SIOCDLIFADDR: delete the specified address.
 793  *      SIOCDLIFADDR with IFLR_PREFIX:
 794  *              delete the first address that matches the specified prefix.
 795  * return values:
 796  *      EINVAL on invalid parameters
 797  *      EADDRNOTAVAIL on prefix match failed/specified address not found
 798  *      other values may be returned from in_ioctl()
 799  *
 800  * NOTE! td might be NULL.
 801  */
 802 static int
 803 in_lifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td)
 804 {
 805         struct if_laddrreq *iflr = (struct if_laddrreq *)data;
 806
 807         /* sanity checks */
 808         if (!data || !ifp) {
 809                 panic("invalid argument to in_lifaddr_ioctl");
 810                 /*NOTRECHED*/
 811         }
 812
 813         switch (cmd) {
 814         case SIOCGLIFADDR:
 815                 /* address must be specified on GET with IFLR_PREFIX */
 816                 if ((iflr->flags & IFLR_PREFIX) == 0)
 817                         break;
 818                 /*FALLTHROUGH*/
 819         case SIOCALIFADDR:
 820         case SIOCDLIFADDR:
 821                 /* address must be specified on ADD and DELETE */
 822                 if (iflr->addr.ss_family != AF_INET)
 823                         return EINVAL;
 824                 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
 825                         return EINVAL;
 826                 /* XXX need improvement */
 827                 if (iflr->dstaddr.ss_family &&
 828                     iflr->dstaddr.ss_family != AF_INET)
 829                         return EINVAL;
 830                 if (iflr->dstaddr.ss_family &&
 831                     iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
 832                         return EINVAL;
 833                 break;
 834         default: /*shouldn't happen*/
 835                 return EOPNOTSUPP;
 836         }
 837         if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
 838                 return EINVAL;
 839
 840         switch (cmd) {
 841         case SIOCALIFADDR:
 842             {
 843                 struct in_aliasreq ifra;
 844
 845                 if (iflr->flags & IFLR_PREFIX)
 846                         return EINVAL;
 847
 848                 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
 849                 bzero(&ifra, sizeof ifra);
 850                 bcopy(iflr->iflr_name, ifra.ifra_name, sizeof ifra.ifra_name);
 851
 852                 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
 853
 854                 if (iflr->dstaddr.ss_family) {  /*XXX*/
 855                         bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
 856                                 iflr->dstaddr.ss_len);
 857                 }
 858
 859                 ifra.ifra_mask.sin_family = AF_INET;
 860                 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
 861                 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
 862
 863                 return in_control_internal(SIOCAIFADDR, (caddr_t)&ifra, ifp,
 864                     td);
 865             }
 866         case SIOCGLIFADDR:
 867         case SIOCDLIFADDR:
 868             {
 869                 struct ifaddr_container *ifac;
 870                 struct in_ifaddr *ia;
 871                 struct in_addr mask, candidate, match;
 872                 struct sockaddr_in *sin;
 873                 int cmp;
 874
 875                 bzero(&mask, sizeof mask);
 876                 if (iflr->flags & IFLR_PREFIX) {
 877                         /* lookup a prefix rather than address. */
 878                         in_len2mask(&mask, iflr->prefixlen);
 879
 880                         sin = (struct sockaddr_in *)&iflr->addr;
 881                         match.s_addr = sin->sin_addr.s_addr;
 882                         match.s_addr &= mask.s_addr;
 883
 884                         /* if you set extra bits, that's wrong */
 885                         if (match.s_addr != sin->sin_addr.s_addr)
 886                                 return EINVAL;
 887
 888                         cmp = 1;
 889                 } else {
 890                         if (cmd == SIOCGLIFADDR) {
 891                                 /* on getting an address, take the 1st match */
 892                                 match.s_addr = 0; /* gcc4 warning */
 893                                 cmp = 0;        /*XXX*/
 894                         } else {
 895                                 /* on deleting an address, do exact match */
 896                                 in_len2mask(&mask, 32);
 897                                 sin = (struct sockaddr_in *)&iflr->addr;
 898                                 match.s_addr = sin->sin_addr.s_addr;
 899
 900                                 cmp = 1;
 901                         }
 902                 }
 903
 904                 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
 905                         struct ifaddr *ifa = ifac->ifa;
 906
 907                         if (ifa->ifa_addr->sa_family != AF_INET6)
 908                                 continue;
 909                         if (!cmp)
 910                                 break;
 911                         candidate.s_addr =
 912                         ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
 913                         candidate.s_addr &= mask.s_addr;
 914                         if (candidate.s_addr == match.s_addr)
 915                                 break;
 916                 }
 917                 if (ifac == NULL)
 918                         return EADDRNOTAVAIL;
 919                 ia = (struct in_ifaddr *)(ifac->ifa);
 920
 921                 if (cmd == SIOCGLIFADDR) {
 922                         /* fill in the if_laddrreq structure */
 923                         bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 924
 925                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 926                                 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
 927                                         ia->ia_dstaddr.sin_len);
 928                         } else
 929                                 bzero(&iflr->dstaddr, sizeof iflr->dstaddr);
 930
 931                         iflr->prefixlen =
 932                                 in_mask2len(&ia->ia_sockmask.sin_addr);
 933
 934                         iflr->flags = 0;        /*XXX*/
 935
 936                         return 0;
 937                 } else {
 938                         struct in_aliasreq ifra;
 939
 940                         /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
 941                         bzero(&ifra, sizeof ifra);
 942                         bcopy(iflr->iflr_name, ifra.ifra_name,
 943                                 sizeof ifra.ifra_name);
 944
 945                         bcopy(&ia->ia_addr, &ifra.ifra_addr,
 946                                 ia->ia_addr.sin_len);
 947                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 948                                 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
 949                                         ia->ia_dstaddr.sin_len);
 950                         }
 951                         bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
 952                                 ia->ia_sockmask.sin_len);
 953
 954                         return in_control_internal(SIOCDIFADDR, (caddr_t)&ifra,
 955                             ifp, td);
 956                 }
 957             }
 958         }
 959
 960         return EOPNOTSUPP;      /*just for safety*/
 961 }
 962
 963 /*
 964  * Delete any existing route for an interface.
 965  */
 966 void
 967 in_ifscrub(struct ifnet *ifp __unused, struct in_ifaddr *ia)
 968 {
 969         in_scrubprefix(ia);
 970 }
 971
 972 /*
 973  * Initialize an interface's internet address
 974  * and routing table entry.
 975  */
 976 static int
 977 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia,
 978           const struct sockaddr_in *sin, int scrub)
 979 {
 980         u_long i = ntohl(sin->sin_addr.s_addr);
 981         struct sockaddr_in oldaddr;
 982         struct ifaddr_container *ifac;
 983         int flags = RTF_UP, error = 0;
 984         int was_hash = 0;
 985
 986         ifac = &ia->ia_ifa.ifa_containers[mycpuid];
 987         oldaddr = ia->ia_addr;
 988
 989         if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH) {
 990                 was_hash = 1;
 991                 in_iahash_remove(ia);
 992         }
 993
 994         ia->ia_addr = *sin;
 995         if (ia->ia_addr.sin_family == AF_INET)
 996                 in_iahash_insert(ia);
 997
 998         /*
 999          * Give the interface a chance to initialize
1000          * if this is its first address,
1001          * and to validate the address if necessary.
1002          */
1003         if (ifp->if_ioctl != NULL) {
1004                 ifnet_serialize_all(ifp);
1005                 error = ifp->if_ioctl(ifp, SIOCSIFADDR, (caddr_t)ia, NULL);
1006                 ifnet_deserialize_all(ifp);
1007                 if (error)
1008                         goto fail;
1009         }
1010
1011         /*
1012          * Delete old route, if requested.
1013          */
1014         if (scrub) {
1015                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
1016                 in_ifscrub(ifp, ia);
1017                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
1018         }
1019
1020         /*
1021          * Calculate netmask/subnetmask.
1022          */
1023         if (IN_CLASSA(i))
1024                 ia->ia_netmask = IN_CLASSA_NET;
1025         else if (IN_CLASSB(i))
1026                 ia->ia_netmask = IN_CLASSB_NET;
1027         else
1028                 ia->ia_netmask = IN_CLASSC_NET;
1029         /*
1030          * The subnet mask usually includes at least the standard network part,
1031          * but may be smaller in the case of supernetting.
1032          * If it is set, we believe it.
1033          */
1034         if (ia->ia_subnetmask == 0) {
1035                 ia->ia_subnetmask = ia->ia_netmask;
1036                 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
1037         } else {
1038                 ia->ia_netmask &= ia->ia_subnetmask;
1039         }
1040         ia->ia_net = i & ia->ia_netmask;
1041         ia->ia_subnet = i & ia->ia_subnetmask;
1042         in_socktrim(&ia->ia_sockmask);
1043
1044         /*
1045          * Add route for the network.
1046          */
1047         ia->ia_ifa.ifa_metric = ifp->if_metric;
1048         if (ifp->if_flags & IFF_BROADCAST) {
1049                 if (ia->ia_subnetmask == IN_RFC3021_MASK) {
1050                         ia->ia_broadaddr.sin_addr.s_addr = INADDR_BROADCAST;
1051                         ia->ia_netbroadcast.s_addr = INADDR_BROADCAST;
1052                 } else {
1053                         ia->ia_broadaddr.sin_addr.s_addr =
1054                             htonl(ia->ia_subnet | ~ia->ia_subnetmask);
1055                         ia->ia_netbroadcast.s_addr =
1056                             htonl(ia->ia_net | ~ia->ia_netmask);
1057                 }
1058         } else if (ifp->if_flags & IFF_LOOPBACK) {
1059                 ia->ia_dstaddr = ia->ia_addr;
1060                 flags |= RTF_HOST;
1061         } else if (ifp->if_flags & IFF_POINTOPOINT) {
1062                 if (ia->ia_dstaddr.sin_family != AF_INET)
1063                         return (0);
1064                 flags |= RTF_HOST;
1065         }
1066
1067         /*
1068          * Ignore the INADDR_ANY address added by DHCP/BOOTP.
1069          */
1070         if (ia->ia_addr.sin_addr.s_addr != INADDR_ANY) {
1071                 error = in_addprefix(ia, flags);
1072                 if (error)
1073                         goto fail;
1074         }
1075
1076         /*
1077          * If the interface supports multicast, join the "all hosts"
1078          * multicast group on that interface.
1079          */
1080         if (ifp->if_flags & IFF_MULTICAST) {
1081                 struct in_addr addr;
1082
1083                 addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
1084                 in_addmulti(&addr, ifp);
1085         }
1086
1087         return (0);
1088
1089 fail:
1090         if (ifac->ifa_listmask & IFA_LIST_IN_IFADDRHASH)
1091                 in_iahash_remove(ia);
1092         ia->ia_addr = oldaddr;
1093         if (was_hash)
1094                 in_iahash_insert(ia);
1095         return (error);
1096 }
1097
1098 #define rtinitflags(x) \
1099         ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
1100             ? RTF_HOST : 0)
1101
1102 /*
1103  * Add a route to prefix ("connected route" in cisco terminology).
1104  * Do nothing, if there are some interface addresses with the same
1105  * prefix already.  This function assumes that the 'target' parent
1106  * interface is UP.
1107  */
1108 static int
1109 in_addprefix(struct in_ifaddr *target, int flags)
1110 {
1111         struct in_ifaddr_container *iac;
1112         struct in_addr prefix, mask;
1113         int error;
1114
1115 #ifdef CARP
1116         /*
1117          * Don't add prefix routes for CARP interfaces.
1118          * Prefix routes creation is handled by CARP
1119          * interfaces themselves.
1120          */
1121         if (target->ia_ifp->if_type == IFT_CARP)
1122                 return 0;
1123 #endif
1124
1125         /*
1126          * Add a loopback route to the interface address.
1127          */
1128         if ((target->ia_ifp->if_flags & IFF_LOOPBACK) == 0)
1129                 ifa_add_loopback_route(&target->ia_ifa,
1130                     (struct sockaddr *)&target->ia_addr);
1131
1132         mask = target->ia_sockmask.sin_addr;
1133         if (flags & RTF_HOST) {
1134                 prefix = target->ia_dstaddr.sin_addr;
1135         } else {
1136                 prefix = target->ia_addr.sin_addr;
1137                 prefix.s_addr &= mask.s_addr;
1138         }
1139
1140         TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1141                 struct in_ifaddr *ia = iac->ia;
1142                 struct in_addr p;
1143
1144                 /* Don't test against self */
1145                 if (ia == target)
1146                         continue;
1147
1148                 /* The tested address does not own a route entry */
1149                 if ((ia->ia_flags & IFA_ROUTE) == 0)
1150                         continue;
1151
1152                 /* Prefix test */
1153                 if (rtinitflags(ia) != 0) {
1154                         p = ia->ia_dstaddr.sin_addr;
1155                 } else {
1156                         p = ia->ia_addr.sin_addr;
1157                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1158                 }
1159                 if (prefix.s_addr != p.s_addr)
1160                         continue;
1161
1162                 /*
1163                  * If the to-be-added address and the currently being
1164                  * tested address are not host addresses, we need to
1165                  * take subnetmask into consideration.
1166                  */
1167                 if (!(flags & RTF_HOST) && rtinitflags(ia) == 0 &&
1168                     mask.s_addr != ia->ia_sockmask.sin_addr.s_addr)
1169                         continue;
1170
1171                 /*
1172                  * If we got a matching prefix route inserted by other
1173                  * interface address, we don't need to bother.
1174                  */
1175                 return 0;
1176         }
1177
1178         /*
1179          * No one seem to have prefix route; insert it.
1180          */
1181         error = rtinit(&target->ia_ifa, RTM_ADD, flags);
1182         if (!error)
1183                 target->ia_flags |= IFA_ROUTE;
1184         return error;
1185 }
1186
1187 /*
1188  * Remove a route to prefix ("connected route" in cisco terminology).
1189  * Re-installs the route by using another interface address, if there's
1190  * one with the same prefix (otherwise we lose the route mistakenly).
1191  */
1192 static void
1193 in_scrubprefix(struct in_ifaddr *target)
1194 {
1195         struct in_ifaddr_container *iac;
1196         struct in_addr prefix, mask;
1197         int error;
1198
1199 #ifdef CARP
1200         /*
1201          * Don't scrub prefix routes for CARP interfaces.
1202          * Prefix routes deletion is handled by CARP
1203          * interfaces themselves.
1204          */
1205         if (target->ia_ifp->if_type == IFT_CARP)
1206                 return;
1207 #endif
1208
1209         /*
1210          * Remove or change the loopback route to the interface address.
1211          */
1212         if (target->ia_addr.sin_addr.s_addr != INADDR_ANY &&
1213             (target->ia_ifp->if_flags & IFF_LOOPBACK) == 0) {
1214                 struct in_ifaddr *ia;
1215                 struct in_addr addr;
1216
1217                 /*
1218                  * rtrequest1() doesn't yet support to change a route (i.e.,
1219                  * RTM_CHANGE), so always delete the old one and then add
1220                  * the new one if needed.
1221                  */
1222                 ifa_del_loopback_route(&target->ia_ifa,
1223                     (struct sockaddr *)&target->ia_addr);
1224
1225                 /*
1226                  * Check whether the host address is still bound to another
1227                  * interface address.  If yes, then re-add a loopback route
1228                  * for it.
1229                  */
1230                 addr = target->ia_addr.sin_addr;
1231                 LIST_FOREACH(iac, INADDR_HASH(addr.s_addr), ia_hash) {
1232                         ia = iac->ia;
1233                         if (ia != target &&
1234                             ia->ia_addr.sin_addr.s_addr == addr.s_addr) {
1235                                 IFAREF(&ia->ia_ifa);
1236                                 ifa_add_loopback_route(&ia->ia_ifa,
1237                                     (struct sockaddr *)&target->ia_addr);
1238                                 IFAFREE(&ia->ia_ifa);
1239                                 break;
1240                         }
1241                 }
1242         }
1243
1244         if ((target->ia_flags & IFA_ROUTE) == 0)
1245                 return;
1246
1247         mask = target->ia_sockmask.sin_addr;
1248         if (rtinitflags(target) != 0) {
1249                 prefix = target->ia_dstaddr.sin_addr;
1250         } else {
1251                 prefix = target->ia_addr.sin_addr;
1252                 prefix.s_addr &= mask.s_addr;
1253         }
1254
1255         TAILQ_FOREACH(iac, &in_ifaddrheads[mycpuid], ia_link) {
1256                 struct in_ifaddr *ia = iac->ia;
1257                 struct in_addr p;
1258
1259                 /* Don't test against self */
1260                 if (ia == target)
1261                         continue;
1262
1263                 /* The tested address already owns a route entry */
1264                 if (ia->ia_flags & IFA_ROUTE)
1265                         continue;
1266
1267                 /*
1268                  * The prefix route of the tested address should
1269                  * never be installed if its parent interface is
1270                  * not UP yet.
1271                  */
1272                 if ((ia->ia_ifp->if_flags & IFF_UP) == 0)
1273                         continue;
1274
1275 #ifdef CARP
1276                 /*
1277                  * Don't add prefix routes for CARP interfaces.
1278                  * Prefix routes creation is handled by CARP
1279                  * interfaces themselves.
1280                  */
1281                 if (ia->ia_ifp->if_type == IFT_CARP)
1282                         continue;
1283 #endif
1284
1285                 /* Prefix test */
1286                 if (rtinitflags(ia) != 0) {
1287                         p = ia->ia_dstaddr.sin_addr;
1288                 } else {
1289                         p = ia->ia_addr.sin_addr;
1290                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1291                 }
1292                 if (prefix.s_addr != p.s_addr)
1293                         continue;
1294
1295                 /*
1296                  * We don't need to test subnetmask here, as what we do
1297                  * in in_addprefix(), since if the the tested address's
1298                  * parent interface is UP, the tested address should own
1299                  * a prefix route entry and we would never reach here.
1300                  */
1301
1302                 /*
1303                  * If we got a matching prefix route, move IFA_ROUTE to him
1304                  */
1305                 rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1306                 target->ia_flags &= ~IFA_ROUTE;
1307
1308                 error = rtinit(&ia->ia_ifa, RTM_ADD, rtinitflags(ia) | RTF_UP);
1309                 if (!error)
1310                         ia->ia_flags |= IFA_ROUTE;
1311                 return;
1312         }
1313
1314         /*
1315          * No candidates for this prefix route; just remove it.
1316          */
1317         rtinit(&target->ia_ifa, RTM_DELETE, rtinitflags(target));
1318         target->ia_flags &= ~IFA_ROUTE;
1319 }
1320
1321 #undef rtinitflags
1322
1323 /*
1324  * Return 1 if the address might be a local broadcast address.
1325  */
1326 int
1327 in_broadcast(struct in_addr in, struct ifnet *ifp)
1328 {
1329         struct ifaddr_container *ifac;
1330         u_long t;
1331
1332         if (in.s_addr == INADDR_BROADCAST ||
1333             in.s_addr == INADDR_ANY)
1334                 return 1;
1335         if (ifp == NULL || (ifp->if_flags & IFF_BROADCAST) == 0)
1336                 return 0;
1337         t = ntohl(in.s_addr);
1338         /*
1339          * Look through the list of addresses for a match
1340          * with a broadcast address.
1341          */
1342 #define ia ((struct in_ifaddr *)ifa)
1343         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
1344                 struct ifaddr *ifa = ifac->ifa;
1345
1346                 if (ifa->ifa_addr->sa_family == AF_INET &&
1347                     (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1348                      in.s_addr == ia->ia_netbroadcast.s_addr ||
1349                      /*
1350                       * Check for old-style (host 0) broadcast, but
1351                       * taking into account that RFC 3021 obsoletes it.
1352                       */
1353                      (ia->ia_subnetmask != IN_RFC3021_MASK &&
1354                      (t == ia->ia_subnet || t == ia->ia_net))) &&
1355                      /*
1356                       * Check for an all one subnetmask. These
1357                       * only exist when an interface gets a secondary
1358                       * address.
1359                       */
1360                      ia->ia_subnetmask != (u_long)0xffffffff)
1361                             return 1;
1362         }
1363         return (0);
1364 #undef ia
1365 }
1366
1367 /*
1368  * Add an address to the list of IP multicast addresses for a given interface.
1369  */
1370 struct in_multi *
1371 in_addmulti(struct in_addr *ap, struct ifnet *ifp)
1372 {
1373         struct in_multi *inm;
1374         int error;
1375         struct sockaddr_in sin;
1376         struct ifmultiaddr *ifma;
1377
1378         ASSERT_NETISR0;
1379
1380         /*
1381          * Call generic routine to add membership or increment
1382          * refcount.  It wants addresses in the form of a sockaddr,
1383          * so we build one here (being careful to zero the unused bytes).
1384          */
1385         bzero(&sin, sizeof sin);
1386         sin.sin_family = AF_INET;
1387         sin.sin_len = sizeof sin;
1388         sin.sin_addr = *ap;
1389         error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
1390         if (error)
1391                 return NULL;
1392
1393         /*
1394          * If ifma->ifma_protospec is null, then if_addmulti() created
1395          * a new record.  Otherwise, we are done.
1396          */
1397         if (ifma->ifma_protospec != NULL)
1398                 return ifma->ifma_protospec;
1399
1400         inm = kmalloc(sizeof *inm, M_IPMADDR, M_INTWAIT | M_ZERO);
1401         inm->inm_addr = *ap;
1402         inm->inm_ifp = ifp;
1403         inm->inm_ifma = ifma;
1404         ifma->ifma_protospec = inm;
1405         LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
1406
1407         /*
1408          * Let IGMP know that we have joined a new IP multicast group.
1409          */
1410         igmp_joingroup(inm);
1411         return inm;
1412 }
1413
1414 /*
1415  * Delete a multicast address record.
1416  */
1417 void
1418 in_delmulti(struct in_multi *inm)
1419 {
1420         struct ifmultiaddr *ifma;
1421         struct in_multi my_inm;
1422
1423         ASSERT_NETISR0;
1424
1425         ifma = inm->inm_ifma;
1426         my_inm.inm_ifp = NULL ; /* don't send the leave msg */
1427         if (ifma->ifma_refcount == 1) {
1428                 /*
1429                  * No remaining claims to this record; let IGMP know that
1430                  * we are leaving the multicast group.
1431                  * But do it after the if_delmulti() which might reset
1432                  * the interface and nuke the packet.
1433                  */
1434                 my_inm = *inm ;
1435                 ifma->ifma_protospec = NULL;
1436                 LIST_REMOVE(inm, inm_link);
1437                 kfree(inm, M_IPMADDR);
1438         }
1439         /* XXX - should be separate API for when we have an ifma? */
1440         if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
1441         if (my_inm.inm_ifp != NULL)
1442                 igmp_leavegroup(&my_inm);
1443 }
1444
1445 void
1446 in_if_down(struct ifnet *ifp)
1447 {
1448         rt_purgecloned(ifp, AF_INET);
1449 }
1450
1451 static void
1452 in_ifdetach_dispatch(netmsg_t nmsg)
1453 {
1454         struct lwkt_msg *lmsg = &nmsg->lmsg;
1455         struct ifnet *ifp = lmsg->u.ms_resultp;
1456         int cpu;
1457
1458         in_pcbpurgeif0(&ripcbinfo, ifp);
1459         for (cpu = 0; cpu < netisr_ncpus; ++cpu)
1460                 in_pcbpurgeif0(&udbinfo[cpu], ifp);
1461
1462         lwkt_replymsg(lmsg, 0);
1463 }
1464
1465 void
1466 in_ifdetach(struct ifnet *ifp)
1467 {
1468         struct netmsg_base nmsg;
1469         struct lwkt_msg *lmsg = &nmsg.lmsg;
1470
1471         netmsg_init(&nmsg, NULL, &curthread->td_msgport, 0,
1472             in_ifdetach_dispatch);
1473         lmsg->u.ms_resultp = ifp;
1474
1475         lwkt_domsg(netisr_cpuport(0), lmsg, 0);
1476 }