sys/netinet/in.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (C) 2001 WIDE Project.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 4. Neither the name of the University nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  *
  30  *      @(#)in.c        8.4 (Berkeley) 1/9/95
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include "opt_carp.h"
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/sockio.h>
  41 #include <sys/malloc.h>
  42 #include <sys/priv.h>
  43 #include <sys/socket.h>
  44 #include <sys/jail.h>
  45 #include <sys/kernel.h>
  46 #include <sys/proc.h>
  47 #include <sys/sysctl.h>
  48 #include <sys/syslog.h>
  49
  50 #include <net/if.h>
  51 #include <net/if_var.h>
  52 #include <net/if_dl.h>
  53 #include <net/if_llatbl.h>
  54 #include <net/if_types.h>
  55 #include <net/route.h>
  56 #include <net/vnet.h>
  57
  58 #include <netinet/in.h>
  59 #include <netinet/in_var.h>
  60 #include <netinet/in_pcb.h>
  61 #include <netinet/ip_var.h>
  62 #include <netinet/igmp_var.h>
  63 #include <netinet/udp.h>
  64 #include <netinet/udp_var.h>
  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 int      in_addprefix(struct in_ifaddr *, int);
  72 static int      in_scrubprefix(struct in_ifaddr *);
  73 static void     in_socktrim(struct sockaddr_in *);
  74 static int      in_ifinit(struct ifnet *,
  75             struct in_ifaddr *, struct sockaddr_in *, int);
  76 static void     in_purgemaddrs(struct ifnet *);
  77
  78 static VNET_DEFINE(int, subnetsarelocal);
  79 static VNET_DEFINE(int, sameprefixcarponly);
  80 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
  81
  82 #define V_subnetsarelocal               VNET(subnetsarelocal)
  83 #define V_sameprefixcarponly            VNET(sameprefixcarponly)
  84 #define V_ripcbinfo                     VNET(ripcbinfo)
  85
  86 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
  87         &VNET_NAME(subnetsarelocal), 0,
  88         "Treat all subnets as directly connected");
  89 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW,
  90         &VNET_NAME(sameprefixcarponly), 0,
  91         "Refuse to create same prefixes on different interfaces");
  92
  93 /*
  94  * Return 1 if an internet address is for a ``local'' host
  95  * (one to which we have a connection).  If subnetsarelocal
  96  * is true, this includes other subnets of the local net.
  97  * Otherwise, it includes only the directly-connected (sub)nets.
  98  */
  99 int
 100 in_localaddr(struct in_addr in)
 101 {
 102         register u_long i = ntohl(in.s_addr);
 103         register struct in_ifaddr *ia;
 104
 105         IN_IFADDR_RLOCK();
 106         if (V_subnetsarelocal) {
 107                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 108                         if ((i & ia->ia_netmask) == ia->ia_net) {
 109                                 IN_IFADDR_RUNLOCK();
 110                                 return (1);
 111                         }
 112                 }
 113         } else {
 114                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 115                         if ((i & ia->ia_subnetmask) == ia->ia_subnet) {
 116                                 IN_IFADDR_RUNLOCK();
 117                                 return (1);
 118                         }
 119                 }
 120         }
 121         IN_IFADDR_RUNLOCK();
 122         return (0);
 123 }
 124
 125 /*
 126  * Return 1 if an internet address is for the local host and configured
 127  * on one of its interfaces.
 128  */
 129 int
 130 in_localip(struct in_addr in)
 131 {
 132         struct in_ifaddr *ia;
 133
 134         IN_IFADDR_RLOCK();
 135         LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
 136                 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr) {
 137                         IN_IFADDR_RUNLOCK();
 138                         return (1);
 139                 }
 140         }
 141         IN_IFADDR_RUNLOCK();
 142         return (0);
 143 }
 144
 145 /*
 146  * Determine whether an IP address is in a reserved set of addresses
 147  * that may not be forwarded, or whether datagrams to that destination
 148  * may be forwarded.
 149  */
 150 int
 151 in_canforward(struct in_addr in)
 152 {
 153         register u_long i = ntohl(in.s_addr);
 154         register u_long net;
 155
 156         if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
 157                 return (0);
 158         if (IN_CLASSA(i)) {
 159                 net = i & IN_CLASSA_NET;
 160                 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
 161                         return (0);
 162         }
 163         return (1);
 164 }
 165
 166 /*
 167  * Trim a mask in a sockaddr
 168  */
 169 static void
 170 in_socktrim(struct sockaddr_in *ap)
 171 {
 172     register char *cplim = (char *) &ap->sin_addr;
 173     register char *cp = (char *) (&ap->sin_addr + 1);
 174
 175     ap->sin_len = 0;
 176     while (--cp >= cplim)
 177         if (*cp) {
 178             (ap)->sin_len = cp - (char *) (ap) + 1;
 179             break;
 180         }
 181 }
 182
 183 static int
 184 in_mask2len(mask)
 185         struct in_addr *mask;
 186 {
 187         int x, y;
 188         u_char *p;
 189
 190         p = (u_char *)mask;
 191         for (x = 0; x < sizeof(*mask); x++) {
 192                 if (p[x] != 0xff)
 193                         break;
 194         }
 195         y = 0;
 196         if (x < sizeof(*mask)) {
 197                 for (y = 0; y < 8; y++) {
 198                         if ((p[x] & (0x80 >> y)) == 0)
 199                                 break;
 200                 }
 201         }
 202         return (x * 8 + y);
 203 }
 204
 205 static void
 206 in_len2mask(struct in_addr *mask, int len)
 207 {
 208         int i;
 209         u_char *p;
 210
 211         p = (u_char *)mask;
 212         bzero(mask, sizeof(*mask));
 213         for (i = 0; i < len / 8; i++)
 214                 p[i] = 0xff;
 215         if (len % 8)
 216                 p[i] = (0xff00 >> (len % 8)) & 0xff;
 217 }
 218
 219 /*
 220  * Generic internet control operations (ioctl's).
 221  *
 222  * ifp is NULL if not an interface-specific ioctl.
 223  */
 224 /* ARGSUSED */
 225 int
 226 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
 227     struct thread *td)
 228 {
 229         register struct ifreq *ifr = (struct ifreq *)data;
 230         register struct in_ifaddr *ia, *iap;
 231         register struct ifaddr *ifa;
 232         struct in_addr allhosts_addr;
 233         struct in_addr dst;
 234         struct in_ifinfo *ii;
 235         struct in_aliasreq *ifra = (struct in_aliasreq *)data;
 236         struct sockaddr_in oldaddr;
 237         int error, hostIsNew, iaIsNew, maskIsNew;
 238         int iaIsFirst;
 239
 240         ia = NULL;
 241         iaIsFirst = 0;
 242         iaIsNew = 0;
 243         allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
 244
 245         /*
 246          * Filter out ioctls we implement directly; forward the rest on to
 247          * in_lifaddr_ioctl() and ifp->if_ioctl().
 248          */
 249         switch (cmd) {
 250         case SIOCAIFADDR:
 251         case SIOCDIFADDR:
 252         case SIOCGIFADDR:
 253         case SIOCGIFBRDADDR:
 254         case SIOCGIFDSTADDR:
 255         case SIOCGIFNETMASK:
 256         case SIOCSIFADDR:
 257         case SIOCSIFBRDADDR:
 258         case SIOCSIFDSTADDR:
 259         case SIOCSIFNETMASK:
 260                 break;
 261
 262         case SIOCALIFADDR:
 263                 if (td != NULL) {
 264                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 265                         if (error)
 266                                 return (error);
 267                 }
 268                 if (ifp == NULL)
 269                         return (EINVAL);
 270                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 271
 272         case SIOCDLIFADDR:
 273                 if (td != NULL) {
 274                         error = priv_check(td, PRIV_NET_DELIFADDR);
 275                         if (error)
 276                                 return (error);
 277                 }
 278                 if (ifp == NULL)
 279                         return (EINVAL);
 280                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 281
 282         case SIOCGLIFADDR:
 283                 if (ifp == NULL)
 284                         return (EINVAL);
 285                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 286
 287         default:
 288                 if (ifp == NULL || ifp->if_ioctl == NULL)
 289                         return (EOPNOTSUPP);
 290                 return ((*ifp->if_ioctl)(ifp, cmd, data));
 291         }
 292
 293         if (ifp == NULL)
 294                 return (EADDRNOTAVAIL);
 295
 296         /*
 297          * Security checks before we get involved in any work.
 298          */
 299         switch (cmd) {
 300         case SIOCAIFADDR:
 301         case SIOCSIFADDR:
 302         case SIOCSIFBRDADDR:
 303         case SIOCSIFNETMASK:
 304         case SIOCSIFDSTADDR:
 305                 if (td != NULL) {
 306                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 307                         if (error)
 308                                 return (error);
 309                 }
 310                 break;
 311
 312         case SIOCDIFADDR:
 313                 if (td != NULL) {
 314                         error = priv_check(td, PRIV_NET_DELIFADDR);
 315                         if (error)
 316                                 return (error);
 317                 }
 318                 break;
 319         }
 320
 321         /*
 322          * Find address for this interface, if it exists.
 323          *
 324          * If an alias address was specified, find that one instead of the
 325          * first one on the interface, if possible.
 326          */
 327         dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
 328         IN_IFADDR_RLOCK();
 329         LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash) {
 330                 if (iap->ia_ifp == ifp &&
 331                     iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
 332                         if (td == NULL || prison_check_ip4(td->td_ucred,
 333                             &dst) == 0)
 334                                 ia = iap;
 335                         break;
 336                 }
 337         }
 338         if (ia != NULL)
 339                 ifa_ref(&ia->ia_ifa);
 340         IN_IFADDR_RUNLOCK();
 341         if (ia == NULL) {
 342                 IF_ADDR_LOCK(ifp);
 343                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 344                         iap = ifatoia(ifa);
 345                         if (iap->ia_addr.sin_family == AF_INET) {
 346                                 if (td != NULL &&
 347                                     prison_check_ip4(td->td_ucred,
 348                                     &iap->ia_addr.sin_addr) != 0)
 349                                         continue;
 350                                 ia = iap;
 351                                 break;
 352                         }
 353                 }
 354                 if (ia != NULL)
 355                         ifa_ref(&ia->ia_ifa);
 356                 IF_ADDR_UNLOCK(ifp);
 357         }
 358         if (ia == NULL)
 359                 iaIsFirst = 1;
 360
 361         error = 0;
 362         switch (cmd) {
 363         case SIOCAIFADDR:
 364         case SIOCDIFADDR:
 365                 if (ifra->ifra_addr.sin_family == AF_INET) {
 366                         struct in_ifaddr *oia;
 367
 368                         IN_IFADDR_RLOCK();
 369                         for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
 370                                 if (ia->ia_ifp == ifp  &&
 371                                     ia->ia_addr.sin_addr.s_addr ==
 372                                     ifra->ifra_addr.sin_addr.s_addr)
 373                                         break;
 374                         }
 375                         if (ia != NULL && ia != oia)
 376                                 ifa_ref(&ia->ia_ifa);
 377                         if (oia != NULL && ia != oia)
 378                                 ifa_free(&oia->ia_ifa);
 379                         IN_IFADDR_RUNLOCK();
 380                         if ((ifp->if_flags & IFF_POINTOPOINT)
 381                             && (cmd == SIOCAIFADDR)
 382                             && (ifra->ifra_dstaddr.sin_addr.s_addr
 383                                 == INADDR_ANY)) {
 384                                 error = EDESTADDRREQ;
 385                                 goto out;
 386                         }
 387                 }
 388                 if (cmd == SIOCDIFADDR && ia == NULL) {
 389                         error = EADDRNOTAVAIL;
 390                         goto out;
 391                 }
 392                 /* FALLTHROUGH */
 393         case SIOCSIFADDR:
 394         case SIOCSIFNETMASK:
 395         case SIOCSIFDSTADDR:
 396                 if (ia == NULL) {
 397                         ia = (struct in_ifaddr *)
 398                                 malloc(sizeof *ia, M_IFADDR, M_NOWAIT |
 399                                     M_ZERO);
 400                         if (ia == NULL) {
 401                                 error = ENOBUFS;
 402                                 goto out;
 403                         }
 404
 405                         ifa = &ia->ia_ifa;
 406                         ifa_init(ifa);
 407                         ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 408                         ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 409                         ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 410
 411                         ia->ia_sockmask.sin_len = 8;
 412                         ia->ia_sockmask.sin_family = AF_INET;
 413                         if (ifp->if_flags & IFF_BROADCAST) {
 414                                 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
 415                                 ia->ia_broadaddr.sin_family = AF_INET;
 416                         }
 417                         ia->ia_ifp = ifp;
 418
 419                         ifa_ref(ifa);                   /* if_addrhead */
 420                         IF_ADDR_LOCK(ifp);
 421                         TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
 422                         IF_ADDR_UNLOCK(ifp);
 423                         ifa_ref(ifa);                   /* in_ifaddrhead */
 424                         IN_IFADDR_WLOCK();
 425                         TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
 426                         IN_IFADDR_WUNLOCK();
 427                         iaIsNew = 1;
 428                 }
 429                 break;
 430
 431         case SIOCSIFBRDADDR:
 432         case SIOCGIFADDR:
 433         case SIOCGIFNETMASK:
 434         case SIOCGIFDSTADDR:
 435         case SIOCGIFBRDADDR:
 436                 if (ia == NULL) {
 437                         error = EADDRNOTAVAIL;
 438                         goto out;
 439                 }
 440                 break;
 441         }
 442
 443         /*
 444          * Most paths in this switch return directly or via out.  Only paths
 445          * that remove the address break in order to hit common removal code.
 446          */
 447         switch (cmd) {
 448         case SIOCGIFADDR:
 449                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
 450                 goto out;
 451
 452         case SIOCGIFBRDADDR:
 453                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 454                         error = EINVAL;
 455                         goto out;
 456                 }
 457                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
 458                 goto out;
 459
 460         case SIOCGIFDSTADDR:
 461                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
 462                         error = EINVAL;
 463                         goto out;
 464                 }
 465                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
 466                 goto out;
 467
 468         case SIOCGIFNETMASK:
 469                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
 470                 goto out;
 471
 472         case SIOCSIFDSTADDR:
 473                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
 474                         error = EINVAL;
 475                         goto out;
 476                 }
 477                 oldaddr = ia->ia_dstaddr;
 478                 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
 479                 if (ifp->if_ioctl != NULL) {
 480                         error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
 481                             (caddr_t)ia);
 482                         if (error) {
 483                                 ia->ia_dstaddr = oldaddr;
 484                                 goto out;
 485                         }
 486                 }
 487                 if (ia->ia_flags & IFA_ROUTE) {
 488                         ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
 489                         rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
 490                         ia->ia_ifa.ifa_dstaddr =
 491                                         (struct sockaddr *)&ia->ia_dstaddr;
 492                         rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
 493                 }
 494                 goto out;
 495
 496         case SIOCSIFBRDADDR:
 497                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 498                         error = EINVAL;
 499                         goto out;
 500                 }
 501                 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 502                 goto out;
 503
 504         case SIOCSIFADDR:
 505                 error = in_ifinit(ifp, ia,
 506                     (struct sockaddr_in *) &ifr->ifr_addr, 1);
 507                 if (error != 0 && iaIsNew)
 508                         break;
 509                 if (error == 0) {
 510                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 511                         if (iaIsFirst &&
 512                             (ifp->if_flags & IFF_MULTICAST) != 0) {
 513                                 error = in_joingroup(ifp, &allhosts_addr,
 514                                     NULL, &ii->ii_allhosts);
 515                         }
 516                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 517                 }
 518                 error = 0;
 519                 goto out;
 520
 521         case SIOCSIFNETMASK:
 522                 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
 523                 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
 524                 goto out;
 525
 526         case SIOCAIFADDR:
 527                 maskIsNew = 0;
 528                 hostIsNew = 1;
 529                 error = 0;
 530                 if (ia->ia_addr.sin_family == AF_INET) {
 531                         if (ifra->ifra_addr.sin_len == 0) {
 532                                 ifra->ifra_addr = ia->ia_addr;
 533                                 hostIsNew = 0;
 534                         } else if (ifra->ifra_addr.sin_addr.s_addr ==
 535                                                ia->ia_addr.sin_addr.s_addr)
 536                                 hostIsNew = 0;
 537                 }
 538                 if (ifra->ifra_mask.sin_len) {
 539                         /*
 540                          * QL: XXX
 541                          * Need to scrub the prefix here in case
 542                          * the issued command is SIOCAIFADDR with
 543                          * the same address, but with a different
 544                          * prefix length. And if the prefix length
 545                          * is the same as before, then the call is
 546                          * un-necessarily executed here.
 547                          */
 548                         in_ifscrub(ifp, ia);
 549                         ia->ia_sockmask = ifra->ifra_mask;
 550                         ia->ia_sockmask.sin_family = AF_INET;
 551                         ia->ia_subnetmask =
 552                              ntohl(ia->ia_sockmask.sin_addr.s_addr);
 553                         maskIsNew = 1;
 554                 }
 555                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 556                     (ifra->ifra_dstaddr.sin_family == AF_INET)) {
 557                         in_ifscrub(ifp, ia);
 558                         ia->ia_dstaddr = ifra->ifra_dstaddr;
 559                         maskIsNew  = 1; /* We lie; but the effect's the same */
 560                 }
 561                 if (ifra->ifra_addr.sin_family == AF_INET &&
 562                     (hostIsNew || maskIsNew))
 563                         error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
 564                 if (error != 0 && iaIsNew)
 565                         goto out;
 566
 567                 if ((ifp->if_flags & IFF_BROADCAST) &&
 568                     (ifra->ifra_broadaddr.sin_family == AF_INET))
 569                         ia->ia_broadaddr = ifra->ifra_broadaddr;
 570                 if (error == 0) {
 571                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 572                         if (iaIsFirst &&
 573                             (ifp->if_flags & IFF_MULTICAST) != 0) {
 574                                 error = in_joingroup(ifp, &allhosts_addr,
 575                                     NULL, &ii->ii_allhosts);
 576                         }
 577                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 578                 }
 579                 goto out;
 580
 581         case SIOCDIFADDR:
 582                 /*
 583                  * in_ifscrub kills the interface route.
 584                  */
 585                 in_ifscrub(ifp, ia);
 586
 587                 /*
 588                  * in_ifadown gets rid of all the rest of
 589                  * the routes.  This is not quite the right
 590                  * thing to do, but at least if we are running
 591                  * a routing process they will come back.
 592                  */
 593                 in_ifadown(&ia->ia_ifa, 1);
 594                 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 595                 error = 0;
 596                 break;
 597
 598         default:
 599                 panic("in_control: unsupported ioctl");
 600         }
 601
 602         IF_ADDR_LOCK(ifp);
 603         TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
 604         IF_ADDR_UNLOCK(ifp);
 605         ifa_free(&ia->ia_ifa);                          /* if_addrhead */
 606
 607         IN_IFADDR_WLOCK();
 608         TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
 609         if (ia->ia_addr.sin_family == AF_INET) {
 610                 struct in_ifaddr *if_ia;
 611
 612                 LIST_REMOVE(ia, ia_hash);
 613                 IN_IFADDR_WUNLOCK();
 614                 /*
 615                  * If this is the last IPv4 address configured on this
 616                  * interface, leave the all-hosts group.
 617                  * No state-change report need be transmitted.
 618                  */
 619                 if_ia = NULL;
 620                 IFP_TO_IA(ifp, if_ia);
 621                 if (if_ia == NULL) {
 622                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 623                         IN_MULTI_LOCK();
 624                         if (ii->ii_allhosts) {
 625                                 (void)in_leavegroup_locked(ii->ii_allhosts,
 626                                     NULL);
 627                                 ii->ii_allhosts = NULL;
 628                         }
 629                         IN_MULTI_UNLOCK();
 630                 } else
 631                         ifa_free(&if_ia->ia_ifa);
 632         } else
 633                 IN_IFADDR_WUNLOCK();
 634         ifa_free(&ia->ia_ifa);                          /* in_ifaddrhead */
 635 out:
 636         if (ia != NULL)
 637                 ifa_free(&ia->ia_ifa);
 638         return (error);
 639 }
 640
 641 /*
 642  * SIOC[GAD]LIFADDR.
 643  *      SIOCGLIFADDR: get first address. (?!?)
 644  *      SIOCGLIFADDR with IFLR_PREFIX:
 645  *              get first address that matches the specified prefix.
 646  *      SIOCALIFADDR: add the specified address.
 647  *      SIOCALIFADDR with IFLR_PREFIX:
 648  *              EINVAL since we can't deduce hostid part of the address.
 649  *      SIOCDLIFADDR: delete the specified address.
 650  *      SIOCDLIFADDR with IFLR_PREFIX:
 651  *              delete the first address that matches the specified prefix.
 652  * return values:
 653  *      EINVAL on invalid parameters
 654  *      EADDRNOTAVAIL on prefix match failed/specified address not found
 655  *      other values may be returned from in_ioctl()
 656  */
 657 static int
 658 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
 659     struct ifnet *ifp, struct thread *td)
 660 {
 661         struct if_laddrreq *iflr = (struct if_laddrreq *)data;
 662         struct ifaddr *ifa;
 663
 664         /* sanity checks */
 665         if (data == NULL || ifp == NULL) {
 666                 panic("invalid argument to in_lifaddr_ioctl");
 667                 /*NOTRECHED*/
 668         }
 669
 670         switch (cmd) {
 671         case SIOCGLIFADDR:
 672                 /* address must be specified on GET with IFLR_PREFIX */
 673                 if ((iflr->flags & IFLR_PREFIX) == 0)
 674                         break;
 675                 /*FALLTHROUGH*/
 676         case SIOCALIFADDR:
 677         case SIOCDLIFADDR:
 678                 /* address must be specified on ADD and DELETE */
 679                 if (iflr->addr.ss_family != AF_INET)
 680                         return (EINVAL);
 681                 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
 682                         return (EINVAL);
 683                 /* XXX need improvement */
 684                 if (iflr->dstaddr.ss_family
 685                  && iflr->dstaddr.ss_family != AF_INET)
 686                         return (EINVAL);
 687                 if (iflr->dstaddr.ss_family
 688                  && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
 689                         return (EINVAL);
 690                 break;
 691         default: /*shouldn't happen*/
 692                 return (EOPNOTSUPP);
 693         }
 694         if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
 695                 return (EINVAL);
 696
 697         switch (cmd) {
 698         case SIOCALIFADDR:
 699             {
 700                 struct in_aliasreq ifra;
 701
 702                 if (iflr->flags & IFLR_PREFIX)
 703                         return (EINVAL);
 704
 705                 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
 706                 bzero(&ifra, sizeof(ifra));
 707                 bcopy(iflr->iflr_name, ifra.ifra_name,
 708                         sizeof(ifra.ifra_name));
 709
 710                 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
 711
 712                 if (iflr->dstaddr.ss_family) {  /*XXX*/
 713                         bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
 714                                 iflr->dstaddr.ss_len);
 715                 }
 716
 717                 ifra.ifra_mask.sin_family = AF_INET;
 718                 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
 719                 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
 720
 721                 return (in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td));
 722             }
 723         case SIOCGLIFADDR:
 724         case SIOCDLIFADDR:
 725             {
 726                 struct in_ifaddr *ia;
 727                 struct in_addr mask, candidate, match;
 728                 struct sockaddr_in *sin;
 729
 730                 bzero(&mask, sizeof(mask));
 731                 bzero(&match, sizeof(match));
 732                 if (iflr->flags & IFLR_PREFIX) {
 733                         /* lookup a prefix rather than address. */
 734                         in_len2mask(&mask, iflr->prefixlen);
 735
 736                         sin = (struct sockaddr_in *)&iflr->addr;
 737                         match.s_addr = sin->sin_addr.s_addr;
 738                         match.s_addr &= mask.s_addr;
 739
 740                         /* if you set extra bits, that's wrong */
 741                         if (match.s_addr != sin->sin_addr.s_addr)
 742                                 return (EINVAL);
 743
 744                 } else {
 745                         /* on getting an address, take the 1st match */
 746                         /* on deleting an address, do exact match */
 747                         if (cmd != SIOCGLIFADDR) {
 748                                 in_len2mask(&mask, 32);
 749                                 sin = (struct sockaddr_in *)&iflr->addr;
 750                                 match.s_addr = sin->sin_addr.s_addr;
 751                         }
 752                 }
 753
 754                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 755                         if (ifa->ifa_addr->sa_family != AF_INET6)
 756                                 continue;
 757                         if (match.s_addr == 0)
 758                                 break;
 759                         candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
 760                         candidate.s_addr &= mask.s_addr;
 761                         if (candidate.s_addr == match.s_addr)
 762                                 break;
 763                 }
 764                 if (ifa == NULL)
 765                         return (EADDRNOTAVAIL);
 766                 ia = (struct in_ifaddr *)ifa;
 767
 768                 if (cmd == SIOCGLIFADDR) {
 769                         /* fill in the if_laddrreq structure */
 770                         bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 771
 772                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 773                                 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
 774                                         ia->ia_dstaddr.sin_len);
 775                         } else
 776                                 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
 777
 778                         iflr->prefixlen =
 779                                 in_mask2len(&ia->ia_sockmask.sin_addr);
 780
 781                         iflr->flags = 0;        /*XXX*/
 782
 783                         return (0);
 784                 } else {
 785                         struct in_aliasreq ifra;
 786
 787                         /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
 788                         bzero(&ifra, sizeof(ifra));
 789                         bcopy(iflr->iflr_name, ifra.ifra_name,
 790                                 sizeof(ifra.ifra_name));
 791
 792                         bcopy(&ia->ia_addr, &ifra.ifra_addr,
 793                                 ia->ia_addr.sin_len);
 794                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 795                                 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
 796                                         ia->ia_dstaddr.sin_len);
 797                         }
 798                         bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
 799                                 ia->ia_sockmask.sin_len);
 800
 801                         return (in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
 802                             ifp, td));
 803                 }
 804             }
 805         }
 806
 807         return (EOPNOTSUPP);    /*just for safety*/
 808 }
 809
 810 /*
 811  * Delete any existing route for an interface.
 812  */
 813 void
 814 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
 815 {
 816
 817         in_scrubprefix(ia);
 818 }
 819
 820 /*
 821  * Initialize an interface's internet address
 822  * and routing table entry.
 823  */
 824 static int
 825 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
 826     int scrub)
 827 {
 828         register u_long i = ntohl(sin->sin_addr.s_addr);
 829         struct sockaddr_in oldaddr;
 830         int s = splimp(), flags = RTF_UP, error = 0;
 831
 832         oldaddr = ia->ia_addr;
 833         if (oldaddr.sin_family == AF_INET)
 834                 LIST_REMOVE(ia, ia_hash);
 835         ia->ia_addr = *sin;
 836         if (ia->ia_addr.sin_family == AF_INET) {
 837                 IN_IFADDR_WLOCK();
 838                 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
 839                     ia, ia_hash);
 840                 IN_IFADDR_WUNLOCK();
 841         }
 842         /*
 843          * Give the interface a chance to initialize
 844          * if this is its first address,
 845          * and to validate the address if necessary.
 846          */
 847         if (ifp->if_ioctl != NULL) {
 848                 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
 849                 if (error) {
 850                         splx(s);
 851                         /* LIST_REMOVE(ia, ia_hash) is done in in_control */
 852                         ia->ia_addr = oldaddr;
 853                         IN_IFADDR_WLOCK();
 854                         if (ia->ia_addr.sin_family == AF_INET)
 855                                 LIST_INSERT_HEAD(INADDR_HASH(
 856                                     ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
 857                         else
 858                                 /*
 859                                  * If oldaddr family is not AF_INET (e.g.
 860                                  * interface has been just created) in_control
 861                                  * does not call LIST_REMOVE, and we end up
 862                                  * with bogus ia entries in hash
 863                                  */
 864                                 LIST_REMOVE(ia, ia_hash);
 865                         IN_IFADDR_WUNLOCK();
 866                         return (error);
 867                 }
 868         }
 869         splx(s);
 870         if (scrub) {
 871                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
 872                 in_ifscrub(ifp, ia);
 873                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
 874         }
 875         if (IN_CLASSA(i))
 876                 ia->ia_netmask = IN_CLASSA_NET;
 877         else if (IN_CLASSB(i))
 878                 ia->ia_netmask = IN_CLASSB_NET;
 879         else
 880                 ia->ia_netmask = IN_CLASSC_NET;
 881         /*
 882          * The subnet mask usually includes at least the standard network part,
 883          * but may may be smaller in the case of supernetting.
 884          * If it is set, we believe it.
 885          */
 886         if (ia->ia_subnetmask == 0) {
 887                 ia->ia_subnetmask = ia->ia_netmask;
 888                 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
 889         } else
 890                 ia->ia_netmask &= ia->ia_subnetmask;
 891         ia->ia_net = i & ia->ia_netmask;
 892         ia->ia_subnet = i & ia->ia_subnetmask;
 893         in_socktrim(&ia->ia_sockmask);
 894 #ifdef DEV_CARP
 895         /*
 896          * XXX: carp(4) does not have interface route
 897          */
 898         if (ifp->if_type == IFT_CARP)
 899                 return (0);
 900 #endif
 901         /*
 902          * Add route for the network.
 903          */
 904         ia->ia_ifa.ifa_metric = ifp->if_metric;
 905         if (ifp->if_flags & IFF_BROADCAST) {
 906                 ia->ia_broadaddr.sin_addr.s_addr =
 907                         htonl(ia->ia_subnet | ~ia->ia_subnetmask);
 908                 ia->ia_netbroadcast.s_addr =
 909                         htonl(ia->ia_net | ~ ia->ia_netmask);
 910         } else if (ifp->if_flags & IFF_LOOPBACK) {
 911                 ia->ia_dstaddr = ia->ia_addr;
 912                 flags |= RTF_HOST;
 913         } else if (ifp->if_flags & IFF_POINTOPOINT) {
 914                 if (ia->ia_dstaddr.sin_family != AF_INET)
 915                         return (0);
 916                 flags |= RTF_HOST;
 917         }
 918         if ((error = in_addprefix(ia, flags)) != 0)
 919                 return (error);
 920
 921         if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY)
 922                 return (0);
 923
 924         /*
 925          * add a loopback route to self
 926          */
 927         if (V_useloopback && !(ifp->if_flags & IFF_LOOPBACK)) {
 928                 struct route ia_ro;
 929
 930                 bzero(&ia_ro, sizeof(ia_ro));
 931                 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = ia->ia_addr;
 932                 rtalloc_ign_fib(&ia_ro, 0, 0);
 933                 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
 934                     (ia_ro.ro_rt->rt_ifp == V_loif)) {
 935                         RT_LOCK(ia_ro.ro_rt);
 936                         RT_ADDREF(ia_ro.ro_rt);
 937                         RTFREE_LOCKED(ia_ro.ro_rt);
 938                 } else
 939                         error = ifa_add_loopback_route((struct ifaddr *)ia,
 940                                        (struct sockaddr *)&ia->ia_addr);
 941                 if (error == 0)
 942                         ia->ia_flags |= IFA_RTSELF;
 943                 if (ia_ro.ro_rt != NULL)
 944                         RTFREE(ia_ro.ro_rt);
 945         }
 946
 947         return (error);
 948 }
 949
 950 #define rtinitflags(x) \
 951         ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
 952             ? RTF_HOST : 0)
 953 /*
 954  * Check if we have a route for the given prefix already or add one accordingly.
 955  */
 956 static int
 957 in_addprefix(struct in_ifaddr *target, int flags)
 958 {
 959         struct in_ifaddr *ia;
 960         struct in_addr prefix, mask, p, m;
 961         int error;
 962
 963         if ((flags & RTF_HOST) != 0) {
 964                 prefix = target->ia_dstaddr.sin_addr;
 965                 mask.s_addr = 0;
 966         } else {
 967                 prefix = target->ia_addr.sin_addr;
 968                 mask = target->ia_sockmask.sin_addr;
 969                 prefix.s_addr &= mask.s_addr;
 970         }
 971
 972         IN_IFADDR_RLOCK();
 973         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 974                 if (rtinitflags(ia)) {
 975                         p = ia->ia_addr.sin_addr;
 976
 977                         if (prefix.s_addr != p.s_addr)
 978                                 continue;
 979                 } else {
 980                         p = ia->ia_addr.sin_addr;
 981                         m = ia->ia_sockmask.sin_addr;
 982                         p.s_addr &= m.s_addr;
 983
 984                         if (prefix.s_addr != p.s_addr ||
 985                             mask.s_addr != m.s_addr)
 986                                 continue;
 987                 }
 988
 989                 /*
 990                  * If we got a matching prefix route inserted by other
 991                  * interface address, we are done here.
 992                  */
 993                 if (ia->ia_flags & IFA_ROUTE) {
 994                         if (V_sameprefixcarponly &&
 995                             target->ia_ifp->if_type != IFT_CARP &&
 996                             ia->ia_ifp->if_type != IFT_CARP) {
 997                                 IN_IFADDR_RUNLOCK();
 998                                 return (EEXIST);
 999                         } else {
1000                                 struct route pfx_ro;
1001                                 struct sockaddr_in *pfx_addr;
1002                                 struct rtentry msg_rt;
1003
1004                                 /* QL: XXX
1005                                  * This is a bit questionable because there is no
1006                                  * additional route entry added for an address alias.
1007                                  * Therefore this route report is inaccurate. Perhaps
1008                                  * it's better to supply a empty rtentry as how it
1009                                  * is done in in_scrubprefix().
1010                                  */
1011                                 bzero(&pfx_ro, sizeof(pfx_ro));
1012                                 pfx_addr = (struct sockaddr_in *)(&pfx_ro.ro_dst);
1013                                 pfx_addr->sin_len = sizeof(*pfx_addr);
1014                                 pfx_addr->sin_family = AF_INET;
1015                                 pfx_addr->sin_addr = prefix;
1016                                 rtalloc_ign_fib(&pfx_ro, 0, 0);
1017                                 if (pfx_ro.ro_rt != NULL) {
1018                                         msg_rt = *pfx_ro.ro_rt;
1019                                         /* QL: XXX
1020                                          * Point the gateway to the given interface
1021                                          * address as if a new prefix route entry has
1022                                          * been added through the new address alias.
1023                                          * All other parts of the rtentry is accurate,
1024                                          * e.g., rt_key, rt_mask, rt_ifp etc.
1025                                          */
1026                                         msg_rt.rt_gateway =
1027                                                 (struct sockaddr *)&ia->ia_addr;
1028                                         rt_newaddrmsg(RTM_ADD,
1029                                                       (struct ifaddr *)target,
1030                                                       0, &msg_rt);
1031                                         RTFREE(pfx_ro.ro_rt);
1032                                 }
1033
1034                                 IN_IFADDR_RUNLOCK();
1035                                 return (0);
1036                         }
1037                 }
1038         }
1039         IN_IFADDR_RUNLOCK();
1040
1041         /*
1042          * No-one seem to have this prefix route, so we try to insert it.
1043          */
1044         error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
1045         if (!error)
1046                 target->ia_flags |= IFA_ROUTE;
1047         return (error);
1048 }
1049
1050 extern void arp_ifscrub(struct ifnet *ifp, uint32_t addr);
1051
1052 /*
1053  * If there is no other address in the system that can serve a route to the
1054  * same prefix, remove the route.  Hand over the route to the new address
1055  * otherwise.
1056  */
1057 static int
1058 in_scrubprefix(struct in_ifaddr *target)
1059 {
1060         struct in_ifaddr *ia;
1061         struct in_addr prefix, mask, p;
1062         int error = 0;
1063         struct sockaddr_in prefix0, mask0;
1064
1065         /*
1066          * Remove the loopback route to the interface address.
1067          * The "useloopback" setting is not consulted because if the
1068          * user configures an interface address, turns off this
1069          * setting, and then tries to delete that interface address,
1070          * checking the current setting of "useloopback" would leave
1071          * that interface address loopback route untouched, which
1072          * would be wrong. Therefore the interface address loopback route
1073          * deletion is unconditional.
1074          */
1075         if ((target->ia_addr.sin_addr.s_addr != INADDR_ANY) &&
1076             !(target->ia_ifp->if_flags & IFF_LOOPBACK) &&
1077             (target->ia_flags & IFA_RTSELF)) {
1078                 struct route ia_ro;
1079                 int freeit = 0;
1080
1081                 bzero(&ia_ro, sizeof(ia_ro));
1082                 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = target->ia_addr;
1083                 rtalloc_ign_fib(&ia_ro, 0, 0);
1084                 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
1085                     (ia_ro.ro_rt->rt_ifp == V_loif)) {
1086                         RT_LOCK(ia_ro.ro_rt);
1087                         if (ia_ro.ro_rt->rt_refcnt <= 1)
1088                                 freeit = 1;
1089                         else
1090                                 RT_REMREF(ia_ro.ro_rt);
1091                         RTFREE_LOCKED(ia_ro.ro_rt);
1092                 }
1093                 if (freeit)
1094                         error = ifa_del_loopback_route((struct ifaddr *)target,
1095                                        (struct sockaddr *)&target->ia_addr);
1096                 if (error == 0)
1097                         target->ia_flags &= ~IFA_RTSELF;
1098                 /* remove arp cache */
1099                 arp_ifscrub(target->ia_ifp, IA_SIN(target)->sin_addr.s_addr);
1100         }
1101
1102         if ((target->ia_flags & IFA_ROUTE) == 0) {
1103                 struct rtentry rt;
1104
1105                 /* QL: XXX
1106                  * Report a blank rtentry when a route has not been
1107                  * installed for the given interface address.
1108                  */
1109                 bzero(&rt, sizeof(rt));
1110                 rt_newaddrmsg(RTM_DELETE,
1111                               (struct ifaddr *)target,
1112                               0, &rt);
1113                 return (0);
1114         }
1115
1116         if (rtinitflags(target))
1117                 prefix = target->ia_dstaddr.sin_addr;
1118         else {
1119                 prefix = target->ia_addr.sin_addr;
1120                 mask = target->ia_sockmask.sin_addr;
1121                 prefix.s_addr &= mask.s_addr;
1122         }
1123
1124         IN_IFADDR_RLOCK();
1125         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1126                 if (rtinitflags(ia))
1127                         p = ia->ia_dstaddr.sin_addr;
1128                 else {
1129                         p = ia->ia_addr.sin_addr;
1130                         p.s_addr &= ia->ia_sockmask.sin_addr.s_addr;
1131                 }
1132
1133                 if (prefix.s_addr != p.s_addr)
1134                         continue;
1135
1136                 /*
1137                  * If we got a matching prefix address, move IFA_ROUTE and
1138                  * the route itself to it.  Make sure that routing daemons
1139                  * get a heads-up.
1140                  *
1141                  * XXX: a special case for carp(4) interface
1142                  */
1143                 if ((ia->ia_flags & IFA_ROUTE) == 0
1144 #ifdef DEV_CARP
1145                     && (ia->ia_ifp->if_type != IFT_CARP)
1146 #endif
1147                                                         ) {
1148                         IN_IFADDR_RUNLOCK();
1149                         rtinit(&(target->ia_ifa), (int)RTM_DELETE,
1150                             rtinitflags(target));
1151                         target->ia_flags &= ~IFA_ROUTE;
1152
1153                         error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
1154                             rtinitflags(ia) | RTF_UP);
1155                         if (error == 0)
1156                                 ia->ia_flags |= IFA_ROUTE;
1157                         return (error);
1158                 }
1159         }
1160         IN_IFADDR_RUNLOCK();
1161
1162         /*
1163          * remove all L2 entries on the given prefix
1164          */
1165         bzero(&prefix0, sizeof(prefix0));
1166         prefix0.sin_len = sizeof(prefix0);
1167         prefix0.sin_family = AF_INET;
1168         prefix0.sin_addr.s_addr = target->ia_subnet;
1169         bzero(&mask0, sizeof(mask0));
1170         mask0.sin_len = sizeof(mask0);
1171         mask0.sin_family = AF_INET;
1172         mask0.sin_addr.s_addr = target->ia_subnetmask;
1173         lltable_prefix_free(AF_INET, (struct sockaddr *)&prefix0,
1174                             (struct sockaddr *)&mask0);
1175
1176         /*
1177          * As no-one seem to have this prefix, we can remove the route.
1178          */
1179         rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
1180         target->ia_flags &= ~IFA_ROUTE;
1181         return (0);
1182 }
1183
1184 #undef rtinitflags
1185
1186 /*
1187  * Return 1 if the address might be a local broadcast address.
1188  */
1189 int
1190 in_broadcast(struct in_addr in, struct ifnet *ifp)
1191 {
1192         register struct ifaddr *ifa;
1193         u_long t;
1194
1195         if (in.s_addr == INADDR_BROADCAST ||
1196             in.s_addr == INADDR_ANY)
1197                 return (1);
1198         if ((ifp->if_flags & IFF_BROADCAST) == 0)
1199                 return (0);
1200         t = ntohl(in.s_addr);
1201         /*
1202          * Look through the list of addresses for a match
1203          * with a broadcast address.
1204          */
1205 #define ia ((struct in_ifaddr *)ifa)
1206         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
1207                 if (ifa->ifa_addr->sa_family == AF_INET &&
1208                     (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1209                      in.s_addr == ia->ia_netbroadcast.s_addr ||
1210                      /*
1211                       * Check for old-style (host 0) broadcast.
1212                       */
1213                      t == ia->ia_subnet || t == ia->ia_net) &&
1214                      /*
1215                       * Check for an all one subnetmask. These
1216                       * only exist when an interface gets a secondary
1217                       * address.
1218                       */
1219                      ia->ia_subnetmask != (u_long)0xffffffff)
1220                             return (1);
1221         return (0);
1222 #undef ia
1223 }
1224
1225 /*
1226  * On interface removal, clean up IPv4 data structures hung off of the ifnet.
1227  */
1228 void
1229 in_ifdetach(struct ifnet *ifp)
1230 {
1231
1232         in_pcbpurgeif0(&V_ripcbinfo, ifp);
1233         in_pcbpurgeif0(&V_udbinfo, ifp);
1234         in_purgemaddrs(ifp);
1235 }
1236
1237 /*
1238  * Delete all IPv4 multicast address records, and associated link-layer
1239  * multicast address records, associated with ifp.
1240  * XXX It looks like domifdetach runs AFTER the link layer cleanup.
1241  * XXX This should not race with ifma_protospec being set during
1242  * a new allocation, if it does, we have bigger problems.
1243  */
1244 static void
1245 in_purgemaddrs(struct ifnet *ifp)
1246 {
1247         LIST_HEAD(,in_multi) purgeinms;
1248         struct in_multi         *inm, *tinm;
1249         struct ifmultiaddr      *ifma;
1250
1251         LIST_INIT(&purgeinms);
1252         IN_MULTI_LOCK();
1253
1254         /*
1255          * Extract list of in_multi associated with the detaching ifp
1256          * which the PF_INET layer is about to release.
1257          * We need to do this as IF_ADDR_LOCK() may be re-acquired
1258          * by code further down.
1259          */
1260         IF_ADDR_LOCK(ifp);
1261         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1262                 if (ifma->ifma_addr->sa_family != AF_INET ||
1263                     ifma->ifma_protospec == NULL)
1264                         continue;
1265 #if 0
1266                 KASSERT(ifma->ifma_protospec != NULL,
1267                     ("%s: ifma_protospec is NULL", __func__));
1268 #endif
1269                 inm = (struct in_multi *)ifma->ifma_protospec;
1270                 LIST_INSERT_HEAD(&purgeinms, inm, inm_link);
1271         }
1272         IF_ADDR_UNLOCK(ifp);
1273
1274         LIST_FOREACH_SAFE(inm, &purgeinms, inm_link, tinm) {
1275                 LIST_REMOVE(inm, inm_link);
1276                 inm_release_locked(inm);
1277         }
1278         igmp_ifdetach(ifp);
1279
1280         IN_MULTI_UNLOCK();
1281 }
1282
1283 #include <net/if_dl.h>
1284 #include <netinet/if_ether.h>
1285
1286 struct in_llentry {
1287         struct llentry          base;
1288         struct sockaddr_in      l3_addr4;
1289 };
1290
1291 static struct llentry *
1292 in_lltable_new(const struct sockaddr *l3addr, u_int flags)
1293 {
1294         struct in_llentry *lle;
1295
1296         lle = malloc(sizeof(struct in_llentry), M_LLTABLE, M_DONTWAIT | M_ZERO);
1297         if (lle == NULL)                /* NB: caller generates msg */
1298                 return NULL;
1299
1300         callout_init(&lle->base.la_timer, CALLOUT_MPSAFE);
1301         /*
1302          * For IPv4 this will trigger "arpresolve" to generate
1303          * an ARP request.
1304          */
1305         lle->base.la_expire = time_second; /* mark expired */
1306         lle->l3_addr4 = *(const struct sockaddr_in *)l3addr;
1307         lle->base.lle_refcnt = 1;
1308         LLE_LOCK_INIT(&lle->base);
1309         return &lle->base;
1310 }
1311
1312 /*
1313  * Deletes an address from the address table.
1314  * This function is called by the timer functions
1315  * such as arptimer() and nd6_llinfo_timer(), and
1316  * the caller does the locking.
1317  */
1318 static void
1319 in_lltable_free(struct lltable *llt, struct llentry *lle)
1320 {
1321         LLE_WUNLOCK(lle);
1322         LLE_LOCK_DESTROY(lle);
1323         free(lle, M_LLTABLE);
1324 }
1325
1326
1327 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m)       (                       \
1328             (((ntohl((d)->sin_addr.s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
1329
1330 static void
1331 in_lltable_prefix_free(struct lltable *llt,
1332                        const struct sockaddr *prefix,
1333                        const struct sockaddr *mask)
1334 {
1335         const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
1336         const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
1337         struct llentry *lle, *next;
1338         register int i;
1339
1340         for (i=0; i < LLTBL_HASHTBL_SIZE; i++) {
1341                 LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
1342
1343                         if (IN_ARE_MASKED_ADDR_EQUAL((struct sockaddr_in *)L3_ADDR(lle),
1344                                                      pfx, msk)) {
1345                                 callout_drain(&lle->la_timer);
1346                                 LLE_WLOCK(lle);
1347                                 llentry_free(lle);
1348                         }
1349                 }
1350         }
1351 }
1352
1353
1354 static int
1355 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
1356 {
1357         struct rtentry *rt;
1358
1359         KASSERT(l3addr->sa_family == AF_INET,
1360             ("sin_family %d", l3addr->sa_family));
1361
1362         /* XXX rtalloc1 should take a const param */
1363         rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
1364         if (rt == NULL || (rt->rt_flags & RTF_GATEWAY) ||
1365             ((rt->rt_ifp != ifp) && !(flags & LLE_PUB))) {
1366 #ifdef DIAGNOSTIC
1367                 log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
1368                     inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
1369 #endif
1370                 if (rt != NULL)
1371                         RTFREE_LOCKED(rt);
1372                 return (EINVAL);
1373         }
1374         RTFREE_LOCKED(rt);
1375         return 0;
1376 }
1377
1378 /*
1379  * Return NULL if not found or marked for deletion.
1380  * If found return lle read locked.
1381  */
1382 static struct llentry *
1383 in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
1384 {
1385         const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1386         struct ifnet *ifp = llt->llt_ifp;
1387         struct llentry *lle;
1388         struct llentries *lleh;
1389         u_int hashkey;
1390
1391         IF_AFDATA_LOCK_ASSERT(ifp);
1392         KASSERT(l3addr->sa_family == AF_INET,
1393             ("sin_family %d", l3addr->sa_family));
1394
1395         hashkey = sin->sin_addr.s_addr;
1396         lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
1397         LIST_FOREACH(lle, lleh, lle_next) {
1398                 struct sockaddr_in *sa2 = (struct sockaddr_in *)L3_ADDR(lle);
1399                 if (lle->la_flags & LLE_DELETED)
1400                         continue;
1401                 if (sa2->sin_addr.s_addr == sin->sin_addr.s_addr)
1402                         break;
1403         }
1404         if (lle == NULL) {
1405 #ifdef DIAGNOSTIC
1406                 if (flags & LLE_DELETE)
1407                         log(LOG_INFO, "interface address is missing from cache = %p  in delete\n", lle);
1408 #endif
1409                 if (!(flags & LLE_CREATE))
1410                         return (NULL);
1411                 /*
1412                  * A route that covers the given address must have
1413                  * been installed 1st because we are doing a resolution,
1414                  * verify this.
1415                  */
1416                 if (!(flags & LLE_IFADDR) &&
1417                     in_lltable_rtcheck(ifp, flags, l3addr) != 0)
1418                         goto done;
1419
1420                 lle = in_lltable_new(l3addr, flags);
1421                 if (lle == NULL) {
1422                         log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
1423                         goto done;
1424                 }
1425                 lle->la_flags = flags & ~LLE_CREATE;
1426                 if ((flags & (LLE_CREATE | LLE_IFADDR)) == (LLE_CREATE | LLE_IFADDR)) {
1427                         bcopy(IF_LLADDR(ifp), &lle->ll_addr, ifp->if_addrlen);
1428                         lle->la_flags |= (LLE_VALID | LLE_STATIC);
1429                 }
1430
1431                 lle->lle_tbl  = llt;
1432                 lle->lle_head = lleh;
1433                 LIST_INSERT_HEAD(lleh, lle, lle_next);
1434         } else if (flags & LLE_DELETE) {
1435                 if (!(lle->la_flags & LLE_IFADDR) || (flags & LLE_IFADDR)) {
1436                         LLE_WLOCK(lle);
1437                         lle->la_flags = LLE_DELETED;
1438                         EVENTHANDLER_INVOKE(arp_update_event, lle);
1439                         LLE_WUNLOCK(lle);
1440 #ifdef DIAGNOSTIC
1441                         log(LOG_INFO, "ifaddr cache = %p  is deleted\n", lle);
1442 #endif
1443                 }
1444                 lle = (void *)-1;
1445
1446         }
1447         if (LLE_IS_VALID(lle)) {
1448                 if (flags & LLE_EXCLUSIVE)
1449                         LLE_WLOCK(lle);
1450                 else
1451                         LLE_RLOCK(lle);
1452         }
1453 done:
1454         return (lle);
1455 }
1456
1457 static int
1458 in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
1459 {
1460 #define SIN(lle)        ((struct sockaddr_in *) L3_ADDR(lle))
1461         struct ifnet *ifp = llt->llt_ifp;
1462         struct llentry *lle;
1463         /* XXX stack use */
1464         struct {
1465                 struct rt_msghdr        rtm;
1466                 struct sockaddr_inarp   sin;
1467                 struct sockaddr_dl      sdl;
1468         } arpc;
1469         int error, i;
1470
1471         LLTABLE_LOCK_ASSERT();
1472
1473         error = 0;
1474         for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
1475                 LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
1476                         struct sockaddr_dl *sdl;
1477
1478                         /* skip deleted entries */
1479                         if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
1480                                 continue;
1481                         /* Skip if jailed and not a valid IP of the prison. */
1482                         if (prison_if(wr->td->td_ucred, L3_ADDR(lle)) != 0)
1483                                 continue;
1484                         /*
1485                          * produce a msg made of:
1486                          *  struct rt_msghdr;
1487                          *  struct sockaddr_inarp; (IPv4)
1488                          *  struct sockaddr_dl;
1489                          */
1490                         bzero(&arpc, sizeof(arpc));
1491                         arpc.rtm.rtm_msglen = sizeof(arpc);
1492                         arpc.rtm.rtm_version = RTM_VERSION;
1493                         arpc.rtm.rtm_type = RTM_GET;
1494                         arpc.rtm.rtm_flags = RTF_UP;
1495                         arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;
1496                         arpc.sin.sin_family = AF_INET;
1497                         arpc.sin.sin_len = sizeof(arpc.sin);
1498                         arpc.sin.sin_addr.s_addr = SIN(lle)->sin_addr.s_addr;
1499
1500                         /* publish */
1501                         if (lle->la_flags & LLE_PUB) {
1502                                 arpc.rtm.rtm_flags |= RTF_ANNOUNCE;
1503                                 /* proxy only */
1504                                 if (lle->la_flags & LLE_PROXY)
1505                                         arpc.sin.sin_other = SIN_PROXY;
1506                         }
1507
1508                         sdl = &arpc.sdl;
1509                         sdl->sdl_family = AF_LINK;
1510                         sdl->sdl_len = sizeof(*sdl);
1511                         sdl->sdl_index = ifp->if_index;
1512                         sdl->sdl_type = ifp->if_type;
1513                         if ((lle->la_flags & LLE_VALID) == LLE_VALID) {
1514                                 sdl->sdl_alen = ifp->if_addrlen;
1515                                 bcopy(&lle->ll_addr, LLADDR(sdl), ifp->if_addrlen);
1516                         } else {
1517                                 sdl->sdl_alen = 0;
1518                                 bzero(LLADDR(sdl), ifp->if_addrlen);
1519                         }
1520
1521                         arpc.rtm.rtm_rmx.rmx_expire =
1522                             lle->la_flags & LLE_STATIC ? 0 : lle->la_expire;
1523                         arpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA);
1524                         if (lle->la_flags & LLE_STATIC)
1525                                 arpc.rtm.rtm_flags |= RTF_STATIC;
1526                         arpc.rtm.rtm_index = ifp->if_index;
1527                         error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
1528                         if (error)
1529                                 break;
1530                 }
1531         }
1532         return error;
1533 #undef SIN
1534 }
1535
1536 void *
1537 in_domifattach(struct ifnet *ifp)
1538 {
1539         struct in_ifinfo *ii;
1540         struct lltable *llt;
1541
1542         ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
1543
1544         llt = lltable_init(ifp, AF_INET);
1545         if (llt != NULL) {
1546                 llt->llt_new = in_lltable_new;
1547                 llt->llt_free = in_lltable_free;
1548                 llt->llt_prefix_free = in_lltable_prefix_free;
1549                 llt->llt_rtcheck = in_lltable_rtcheck;
1550                 llt->llt_lookup = in_lltable_lookup;
1551                 llt->llt_dump = in_lltable_dump;
1552         }
1553         ii->ii_llt = llt;
1554
1555         ii->ii_igmp = igmp_domifattach(ifp);
1556
1557         return ii;
1558 }
1559
1560 void
1561 in_domifdetach(struct ifnet *ifp, void *aux)
1562 {
1563         struct in_ifinfo *ii = (struct in_ifinfo *)aux;
1564
1565         igmp_domifdetach(ifp);
1566         lltable_free(ii->ii_llt);
1567         free(ii, M_IFADDR);
1568 }