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_mpath.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 #define V_subnetsarelocal               VNET(subnetsarelocal)
  80 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW,
  81         &VNET_NAME(subnetsarelocal), 0,
  82         "Treat all subnets as directly connected");
  83 static VNET_DEFINE(int, sameprefixcarponly);
  84 #define V_sameprefixcarponly            VNET(sameprefixcarponly)
  85 SYSCTL_VNET_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW,
  86         &VNET_NAME(sameprefixcarponly), 0,
  87         "Refuse to create same prefixes on different interfaces");
  88
  89 VNET_DECLARE(struct inpcbinfo, ripcbinfo);
  90 #define V_ripcbinfo                     VNET(ripcbinfo)
  91
  92 /*
  93  * Return 1 if an internet address is for a ``local'' host
  94  * (one to which we have a connection).  If subnetsarelocal
  95  * is true, this includes other subnets of the local net.
  96  * Otherwise, it includes only the directly-connected (sub)nets.
  97  */
  98 int
  99 in_localaddr(struct in_addr in)
 100 {
 101         register u_long i = ntohl(in.s_addr);
 102         register struct in_ifaddr *ia;
 103
 104         IN_IFADDR_RLOCK();
 105         if (V_subnetsarelocal) {
 106                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 107                         if ((i & ia->ia_netmask) == ia->ia_net) {
 108                                 IN_IFADDR_RUNLOCK();
 109                                 return (1);
 110                         }
 111                 }
 112         } else {
 113                 TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
 114                         if ((i & ia->ia_subnetmask) == ia->ia_subnet) {
 115                                 IN_IFADDR_RUNLOCK();
 116                                 return (1);
 117                         }
 118                 }
 119         }
 120         IN_IFADDR_RUNLOCK();
 121         return (0);
 122 }
 123
 124 /*
 125  * Return 1 if an internet address is for the local host and configured
 126  * on one of its interfaces.
 127  */
 128 int
 129 in_localip(struct in_addr in)
 130 {
 131         struct in_ifaddr *ia;
 132
 133         IN_IFADDR_RLOCK();
 134         LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) {
 135                 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr) {
 136                         IN_IFADDR_RUNLOCK();
 137                         return (1);
 138                 }
 139         }
 140         IN_IFADDR_RUNLOCK();
 141         return (0);
 142 }
 143
 144 /*
 145  * Determine whether an IP address is in a reserved set of addresses
 146  * that may not be forwarded, or whether datagrams to that destination
 147  * may be forwarded.
 148  */
 149 int
 150 in_canforward(struct in_addr in)
 151 {
 152         register u_long i = ntohl(in.s_addr);
 153         register u_long net;
 154
 155         if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
 156                 return (0);
 157         if (IN_CLASSA(i)) {
 158                 net = i & IN_CLASSA_NET;
 159                 if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
 160                         return (0);
 161         }
 162         return (1);
 163 }
 164
 165 /*
 166  * Trim a mask in a sockaddr
 167  */
 168 static void
 169 in_socktrim(struct sockaddr_in *ap)
 170 {
 171     register char *cplim = (char *) &ap->sin_addr;
 172     register char *cp = (char *) (&ap->sin_addr + 1);
 173
 174     ap->sin_len = 0;
 175     while (--cp >= cplim)
 176         if (*cp) {
 177             (ap)->sin_len = cp - (char *) (ap) + 1;
 178             break;
 179         }
 180 }
 181
 182 static int
 183 in_mask2len(mask)
 184         struct in_addr *mask;
 185 {
 186         int x, y;
 187         u_char *p;
 188
 189         p = (u_char *)mask;
 190         for (x = 0; x < sizeof(*mask); x++) {
 191                 if (p[x] != 0xff)
 192                         break;
 193         }
 194         y = 0;
 195         if (x < sizeof(*mask)) {
 196                 for (y = 0; y < 8; y++) {
 197                         if ((p[x] & (0x80 >> y)) == 0)
 198                                 break;
 199                 }
 200         }
 201         return (x * 8 + y);
 202 }
 203
 204 static void
 205 in_len2mask(struct in_addr *mask, int len)
 206 {
 207         int i;
 208         u_char *p;
 209
 210         p = (u_char *)mask;
 211         bzero(mask, sizeof(*mask));
 212         for (i = 0; i < len / 8; i++)
 213                 p[i] = 0xff;
 214         if (len % 8)
 215                 p[i] = (0xff00 >> (len % 8)) & 0xff;
 216 }
 217
 218 /*
 219  * Generic internet control operations (ioctl's).
 220  *
 221  * ifp is NULL if not an interface-specific ioctl.
 222  */
 223 /* ARGSUSED */
 224 int
 225 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
 226     struct thread *td)
 227 {
 228         register struct ifreq *ifr = (struct ifreq *)data;
 229         register struct in_ifaddr *ia, *iap;
 230         register struct ifaddr *ifa;
 231         struct in_addr allhosts_addr;
 232         struct in_addr dst;
 233         struct in_ifinfo *ii;
 234         struct in_aliasreq *ifra = (struct in_aliasreq *)data;
 235         struct sockaddr_in oldaddr;
 236         int error, hostIsNew, iaIsNew, maskIsNew;
 237         int iaIsFirst;
 238
 239         ia = NULL;
 240         iaIsFirst = 0;
 241         iaIsNew = 0;
 242         allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
 243
 244         /*
 245          * Filter out ioctls we implement directly; forward the rest on to
 246          * in_lifaddr_ioctl() and ifp->if_ioctl().
 247          */
 248         switch (cmd) {
 249         case SIOCAIFADDR:
 250         case SIOCDIFADDR:
 251         case SIOCGIFADDR:
 252         case SIOCGIFBRDADDR:
 253         case SIOCGIFDSTADDR:
 254         case SIOCGIFNETMASK:
 255         case SIOCSIFADDR:
 256         case SIOCSIFBRDADDR:
 257         case SIOCSIFDSTADDR:
 258         case SIOCSIFNETMASK:
 259                 break;
 260
 261         case SIOCALIFADDR:
 262                 if (td != NULL) {
 263                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 264                         if (error)
 265                                 return (error);
 266                 }
 267                 if (ifp == NULL)
 268                         return (EINVAL);
 269                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 270
 271         case SIOCDLIFADDR:
 272                 if (td != NULL) {
 273                         error = priv_check(td, PRIV_NET_DELIFADDR);
 274                         if (error)
 275                                 return (error);
 276                 }
 277                 if (ifp == NULL)
 278                         return (EINVAL);
 279                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 280
 281         case SIOCGLIFADDR:
 282                 if (ifp == NULL)
 283                         return (EINVAL);
 284                 return in_lifaddr_ioctl(so, cmd, data, ifp, td);
 285
 286         default:
 287                 if (ifp == NULL || ifp->if_ioctl == NULL)
 288                         return (EOPNOTSUPP);
 289                 return ((*ifp->if_ioctl)(ifp, cmd, data));
 290         }
 291
 292         if (ifp == NULL)
 293                 return (EADDRNOTAVAIL);
 294
 295         /*
 296          * Security checks before we get involved in any work.
 297          */
 298         switch (cmd) {
 299         case SIOCAIFADDR:
 300         case SIOCSIFADDR:
 301         case SIOCSIFBRDADDR:
 302         case SIOCSIFNETMASK:
 303         case SIOCSIFDSTADDR:
 304                 if (td != NULL) {
 305                         error = priv_check(td, PRIV_NET_ADDIFADDR);
 306                         if (error)
 307                                 return (error);
 308                 }
 309                 break;
 310
 311         case SIOCDIFADDR:
 312                 if (td != NULL) {
 313                         error = priv_check(td, PRIV_NET_DELIFADDR);
 314                         if (error)
 315                                 return (error);
 316                 }
 317                 break;
 318         }
 319
 320         /*
 321          * Find address for this interface, if it exists.
 322          *
 323          * If an alias address was specified, find that one instead of the
 324          * first one on the interface, if possible.
 325          */
 326         dst = ((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr;
 327         IN_IFADDR_RLOCK();
 328         LIST_FOREACH(iap, INADDR_HASH(dst.s_addr), ia_hash) {
 329                 if (iap->ia_ifp == ifp &&
 330                     iap->ia_addr.sin_addr.s_addr == dst.s_addr) {
 331                         if (td == NULL || prison_check_ip4(td->td_ucred,
 332                             &dst) == 0)
 333                                 ia = iap;
 334                         break;
 335                 }
 336         }
 337         if (ia != NULL)
 338                 ifa_ref(&ia->ia_ifa);
 339         IN_IFADDR_RUNLOCK();
 340         if (ia == NULL) {
 341                 IF_ADDR_LOCK(ifp);
 342                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 343                         iap = ifatoia(ifa);
 344                         if (iap->ia_addr.sin_family == AF_INET) {
 345                                 if (td != NULL &&
 346                                     prison_check_ip4(td->td_ucred,
 347                                     &iap->ia_addr.sin_addr) != 0)
 348                                         continue;
 349                                 ia = iap;
 350                                 break;
 351                         }
 352                 }
 353                 if (ia != NULL)
 354                         ifa_ref(&ia->ia_ifa);
 355                 IF_ADDR_UNLOCK(ifp);
 356         }
 357         if (ia == NULL)
 358                 iaIsFirst = 1;
 359
 360         error = 0;
 361         switch (cmd) {
 362         case SIOCAIFADDR:
 363         case SIOCDIFADDR:
 364                 if (ifra->ifra_addr.sin_family == AF_INET) {
 365                         struct in_ifaddr *oia;
 366
 367                         IN_IFADDR_RLOCK();
 368                         for (oia = ia; ia; ia = TAILQ_NEXT(ia, ia_link)) {
 369                                 if (ia->ia_ifp == ifp  &&
 370                                     ia->ia_addr.sin_addr.s_addr ==
 371                                     ifra->ifra_addr.sin_addr.s_addr)
 372                                         break;
 373                         }
 374                         if (ia != NULL && ia != oia)
 375                                 ifa_ref(&ia->ia_ifa);
 376                         if (oia != NULL && ia != oia)
 377                                 ifa_free(&oia->ia_ifa);
 378                         IN_IFADDR_RUNLOCK();
 379                         if ((ifp->if_flags & IFF_POINTOPOINT)
 380                             && (cmd == SIOCAIFADDR)
 381                             && (ifra->ifra_dstaddr.sin_addr.s_addr
 382                                 == INADDR_ANY)) {
 383                                 error = EDESTADDRREQ;
 384                                 goto out;
 385                         }
 386                 }
 387                 if (cmd == SIOCDIFADDR && ia == NULL) {
 388                         error = EADDRNOTAVAIL;
 389                         goto out;
 390                 }
 391                 /* FALLTHROUGH */
 392         case SIOCSIFADDR:
 393         case SIOCSIFNETMASK:
 394         case SIOCSIFDSTADDR:
 395                 if (ia == NULL) {
 396                         ia = (struct in_ifaddr *)
 397                                 malloc(sizeof *ia, M_IFADDR, M_NOWAIT |
 398                                     M_ZERO);
 399                         if (ia == NULL) {
 400                                 error = ENOBUFS;
 401                                 goto out;
 402                         }
 403
 404                         ifa = &ia->ia_ifa;
 405                         ifa_init(ifa);
 406                         ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
 407                         ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
 408                         ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
 409
 410                         ia->ia_sockmask.sin_len = 8;
 411                         ia->ia_sockmask.sin_family = AF_INET;
 412                         if (ifp->if_flags & IFF_BROADCAST) {
 413                                 ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
 414                                 ia->ia_broadaddr.sin_family = AF_INET;
 415                         }
 416                         ia->ia_ifp = ifp;
 417
 418                         ifa_ref(ifa);                   /* if_addrhead */
 419                         IF_ADDR_LOCK(ifp);
 420                         TAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link);
 421                         IF_ADDR_UNLOCK(ifp);
 422                         ifa_ref(ifa);                   /* in_ifaddrhead */
 423                         IN_IFADDR_WLOCK();
 424                         TAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link);
 425                         IN_IFADDR_WUNLOCK();
 426                         iaIsNew = 1;
 427                 }
 428                 break;
 429
 430         case SIOCSIFBRDADDR:
 431         case SIOCGIFADDR:
 432         case SIOCGIFNETMASK:
 433         case SIOCGIFDSTADDR:
 434         case SIOCGIFBRDADDR:
 435                 if (ia == NULL) {
 436                         error = EADDRNOTAVAIL;
 437                         goto out;
 438                 }
 439                 break;
 440         }
 441
 442         /*
 443          * Most paths in this switch return directly or via out.  Only paths
 444          * that remove the address break in order to hit common removal code.
 445          */
 446         switch (cmd) {
 447         case SIOCGIFADDR:
 448                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
 449                 goto out;
 450
 451         case SIOCGIFBRDADDR:
 452                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 453                         error = EINVAL;
 454                         goto out;
 455                 }
 456                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
 457                 goto out;
 458
 459         case SIOCGIFDSTADDR:
 460                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
 461                         error = EINVAL;
 462                         goto out;
 463                 }
 464                 *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
 465                 goto out;
 466
 467         case SIOCGIFNETMASK:
 468                 *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
 469                 goto out;
 470
 471         case SIOCSIFDSTADDR:
 472                 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) {
 473                         error = EINVAL;
 474                         goto out;
 475                 }
 476                 oldaddr = ia->ia_dstaddr;
 477                 ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
 478                 if (ifp->if_ioctl != NULL) {
 479                         error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR,
 480                             (caddr_t)ia);
 481                         if (error) {
 482                                 ia->ia_dstaddr = oldaddr;
 483                                 goto out;
 484                         }
 485                 }
 486                 if (ia->ia_flags & IFA_ROUTE) {
 487                         ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
 488                         rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
 489                         ia->ia_ifa.ifa_dstaddr =
 490                                         (struct sockaddr *)&ia->ia_dstaddr;
 491                         rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
 492                 }
 493                 goto out;
 494
 495         case SIOCSIFBRDADDR:
 496                 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
 497                         error = EINVAL;
 498                         goto out;
 499                 }
 500                 ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 501                 goto out;
 502
 503         case SIOCSIFADDR:
 504                 error = in_ifinit(ifp, ia,
 505                     (struct sockaddr_in *) &ifr->ifr_addr, 1);
 506                 if (error != 0 && iaIsNew)
 507                         break;
 508                 if (error == 0) {
 509                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 510                         if (iaIsFirst &&
 511                             (ifp->if_flags & IFF_MULTICAST) != 0) {
 512                                 error = in_joingroup(ifp, &allhosts_addr,
 513                                     NULL, &ii->ii_allhosts);
 514                         }
 515                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 516                 }
 517                 error = 0;
 518                 goto out;
 519
 520         case SIOCSIFNETMASK:
 521                 ia->ia_sockmask.sin_addr = ifra->ifra_addr.sin_addr;
 522                 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr);
 523                 goto out;
 524
 525         case SIOCAIFADDR:
 526                 maskIsNew = 0;
 527                 hostIsNew = 1;
 528                 error = 0;
 529                 if (ia->ia_addr.sin_family == AF_INET) {
 530                         if (ifra->ifra_addr.sin_len == 0) {
 531                                 ifra->ifra_addr = ia->ia_addr;
 532                                 hostIsNew = 0;
 533                         } else if (ifra->ifra_addr.sin_addr.s_addr ==
 534                                                ia->ia_addr.sin_addr.s_addr)
 535                                 hostIsNew = 0;
 536                 }
 537                 if (ifra->ifra_mask.sin_len) {
 538                         /*
 539                          * QL: XXX
 540                          * Need to scrub the prefix here in case
 541                          * the issued command is SIOCAIFADDR with
 542                          * the same address, but with a different
 543                          * prefix length. And if the prefix length
 544                          * is the same as before, then the call is
 545                          * un-necessarily executed here.
 546                          */
 547                         in_ifscrub(ifp, ia);
 548                         ia->ia_sockmask = ifra->ifra_mask;
 549                         ia->ia_sockmask.sin_family = AF_INET;
 550                         ia->ia_subnetmask =
 551                              ntohl(ia->ia_sockmask.sin_addr.s_addr);
 552                         maskIsNew = 1;
 553                 }
 554                 if ((ifp->if_flags & IFF_POINTOPOINT) &&
 555                     (ifra->ifra_dstaddr.sin_family == AF_INET)) {
 556                         in_ifscrub(ifp, ia);
 557                         ia->ia_dstaddr = ifra->ifra_dstaddr;
 558                         maskIsNew  = 1; /* We lie; but the effect's the same */
 559                 }
 560                 if (ifra->ifra_addr.sin_family == AF_INET &&
 561                     (hostIsNew || maskIsNew))
 562                         error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
 563                 if (error != 0 && iaIsNew)
 564                         goto out;
 565
 566                 if ((ifp->if_flags & IFF_BROADCAST) &&
 567                     (ifra->ifra_broadaddr.sin_family == AF_INET))
 568                         ia->ia_broadaddr = ifra->ifra_broadaddr;
 569                 if (error == 0) {
 570                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 571                         if (iaIsFirst &&
 572                             (ifp->if_flags & IFF_MULTICAST) != 0) {
 573                                 error = in_joingroup(ifp, &allhosts_addr,
 574                                     NULL, &ii->ii_allhosts);
 575                         }
 576                         EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 577                 }
 578                 goto out;
 579
 580         case SIOCDIFADDR:
 581                 /*
 582                  * in_ifscrub kills the interface route.
 583                  */
 584                 in_ifscrub(ifp, ia);
 585
 586                 /*
 587                  * in_ifadown gets rid of all the rest of
 588                  * the routes.  This is not quite the right
 589                  * thing to do, but at least if we are running
 590                  * a routing process they will come back.
 591                  */
 592                 in_ifadown(&ia->ia_ifa, 1);
 593                 EVENTHANDLER_INVOKE(ifaddr_event, ifp);
 594                 error = 0;
 595                 break;
 596
 597         default:
 598                 panic("in_control: unsupported ioctl");
 599         }
 600
 601         IF_ADDR_LOCK(ifp);
 602         /* Re-check that ia is still part of the list. */
 603         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 604                 if (ifa == &ia->ia_ifa)
 605                         break;
 606         }
 607         if (ifa == NULL) {
 608                 /*
 609                  * If we lost the race with another thread, there is no need to
 610                  * try it again for the next loop as there is no other exit
 611                  * path between here and out.
 612                  */
 613                 IF_ADDR_UNLOCK(ifp);
 614                 error = EADDRNOTAVAIL;
 615                 goto out;
 616         }
 617         TAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifa_link);
 618         IF_ADDR_UNLOCK(ifp);
 619         ifa_free(&ia->ia_ifa);                          /* if_addrhead */
 620
 621         IN_IFADDR_WLOCK();
 622         TAILQ_REMOVE(&V_in_ifaddrhead, ia, ia_link);
 623         if (ia->ia_addr.sin_family == AF_INET) {
 624                 struct in_ifaddr *if_ia;
 625
 626                 LIST_REMOVE(ia, ia_hash);
 627                 IN_IFADDR_WUNLOCK();
 628                 /*
 629                  * If this is the last IPv4 address configured on this
 630                  * interface, leave the all-hosts group.
 631                  * No state-change report need be transmitted.
 632                  */
 633                 if_ia = NULL;
 634                 IFP_TO_IA(ifp, if_ia);
 635                 if (if_ia == NULL) {
 636                         ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]);
 637                         IN_MULTI_LOCK();
 638                         if (ii->ii_allhosts) {
 639                                 (void)in_leavegroup_locked(ii->ii_allhosts,
 640                                     NULL);
 641                                 ii->ii_allhosts = NULL;
 642                         }
 643                         IN_MULTI_UNLOCK();
 644                 } else
 645                         ifa_free(&if_ia->ia_ifa);
 646         } else
 647                 IN_IFADDR_WUNLOCK();
 648         ifa_free(&ia->ia_ifa);                          /* in_ifaddrhead */
 649 out:
 650         if (ia != NULL)
 651                 ifa_free(&ia->ia_ifa);
 652         return (error);
 653 }
 654
 655 /*
 656  * SIOC[GAD]LIFADDR.
 657  *      SIOCGLIFADDR: get first address. (?!?)
 658  *      SIOCGLIFADDR with IFLR_PREFIX:
 659  *              get first address that matches the specified prefix.
 660  *      SIOCALIFADDR: add the specified address.
 661  *      SIOCALIFADDR with IFLR_PREFIX:
 662  *              EINVAL since we can't deduce hostid part of the address.
 663  *      SIOCDLIFADDR: delete the specified address.
 664  *      SIOCDLIFADDR with IFLR_PREFIX:
 665  *              delete the first address that matches the specified prefix.
 666  * return values:
 667  *      EINVAL on invalid parameters
 668  *      EADDRNOTAVAIL on prefix match failed/specified address not found
 669  *      other values may be returned from in_ioctl()
 670  */
 671 static int
 672 in_lifaddr_ioctl(struct socket *so, u_long cmd, caddr_t data,
 673     struct ifnet *ifp, struct thread *td)
 674 {
 675         struct if_laddrreq *iflr = (struct if_laddrreq *)data;
 676         struct ifaddr *ifa;
 677
 678         /* sanity checks */
 679         if (data == NULL || ifp == NULL) {
 680                 panic("invalid argument to in_lifaddr_ioctl");
 681                 /*NOTRECHED*/
 682         }
 683
 684         switch (cmd) {
 685         case SIOCGLIFADDR:
 686                 /* address must be specified on GET with IFLR_PREFIX */
 687                 if ((iflr->flags & IFLR_PREFIX) == 0)
 688                         break;
 689                 /*FALLTHROUGH*/
 690         case SIOCALIFADDR:
 691         case SIOCDLIFADDR:
 692                 /* address must be specified on ADD and DELETE */
 693                 if (iflr->addr.ss_family != AF_INET)
 694                         return (EINVAL);
 695                 if (iflr->addr.ss_len != sizeof(struct sockaddr_in))
 696                         return (EINVAL);
 697                 /* XXX need improvement */
 698                 if (iflr->dstaddr.ss_family
 699                  && iflr->dstaddr.ss_family != AF_INET)
 700                         return (EINVAL);
 701                 if (iflr->dstaddr.ss_family
 702                  && iflr->dstaddr.ss_len != sizeof(struct sockaddr_in))
 703                         return (EINVAL);
 704                 break;
 705         default: /*shouldn't happen*/
 706                 return (EOPNOTSUPP);
 707         }
 708         if (sizeof(struct in_addr) * 8 < iflr->prefixlen)
 709                 return (EINVAL);
 710
 711         switch (cmd) {
 712         case SIOCALIFADDR:
 713             {
 714                 struct in_aliasreq ifra;
 715
 716                 if (iflr->flags & IFLR_PREFIX)
 717                         return (EINVAL);
 718
 719                 /* copy args to in_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
 720                 bzero(&ifra, sizeof(ifra));
 721                 bcopy(iflr->iflr_name, ifra.ifra_name,
 722                         sizeof(ifra.ifra_name));
 723
 724                 bcopy(&iflr->addr, &ifra.ifra_addr, iflr->addr.ss_len);
 725
 726                 if (iflr->dstaddr.ss_family) {  /*XXX*/
 727                         bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
 728                                 iflr->dstaddr.ss_len);
 729                 }
 730
 731                 ifra.ifra_mask.sin_family = AF_INET;
 732                 ifra.ifra_mask.sin_len = sizeof(struct sockaddr_in);
 733                 in_len2mask(&ifra.ifra_mask.sin_addr, iflr->prefixlen);
 734
 735                 return (in_control(so, SIOCAIFADDR, (caddr_t)&ifra, ifp, td));
 736             }
 737         case SIOCGLIFADDR:
 738         case SIOCDLIFADDR:
 739             {
 740                 struct in_ifaddr *ia;
 741                 struct in_addr mask, candidate, match;
 742                 struct sockaddr_in *sin;
 743
 744                 bzero(&mask, sizeof(mask));
 745                 bzero(&match, sizeof(match));
 746                 if (iflr->flags & IFLR_PREFIX) {
 747                         /* lookup a prefix rather than address. */
 748                         in_len2mask(&mask, iflr->prefixlen);
 749
 750                         sin = (struct sockaddr_in *)&iflr->addr;
 751                         match.s_addr = sin->sin_addr.s_addr;
 752                         match.s_addr &= mask.s_addr;
 753
 754                         /* if you set extra bits, that's wrong */
 755                         if (match.s_addr != sin->sin_addr.s_addr)
 756                                 return (EINVAL);
 757
 758                 } else {
 759                         /* on getting an address, take the 1st match */
 760                         /* on deleting an address, do exact match */
 761                         if (cmd != SIOCGLIFADDR) {
 762                                 in_len2mask(&mask, 32);
 763                                 sin = (struct sockaddr_in *)&iflr->addr;
 764                                 match.s_addr = sin->sin_addr.s_addr;
 765                         }
 766                 }
 767
 768                 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 769                         if (ifa->ifa_addr->sa_family != AF_INET6)
 770                                 continue;
 771                         if (match.s_addr == 0)
 772                                 break;
 773                         candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
 774                         candidate.s_addr &= mask.s_addr;
 775                         if (candidate.s_addr == match.s_addr)
 776                                 break;
 777                 }
 778                 if (ifa == NULL)
 779                         return (EADDRNOTAVAIL);
 780                 ia = (struct in_ifaddr *)ifa;
 781
 782                 if (cmd == SIOCGLIFADDR) {
 783                         /* fill in the if_laddrreq structure */
 784                         bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 785
 786                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 787                                 bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
 788                                         ia->ia_dstaddr.sin_len);
 789                         } else
 790                                 bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));
 791
 792                         iflr->prefixlen =
 793                                 in_mask2len(&ia->ia_sockmask.sin_addr);
 794
 795                         iflr->flags = 0;        /*XXX*/
 796
 797                         return (0);
 798                 } else {
 799                         struct in_aliasreq ifra;
 800
 801                         /* fill in_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
 802                         bzero(&ifra, sizeof(ifra));
 803                         bcopy(iflr->iflr_name, ifra.ifra_name,
 804                                 sizeof(ifra.ifra_name));
 805
 806                         bcopy(&ia->ia_addr, &ifra.ifra_addr,
 807                                 ia->ia_addr.sin_len);
 808                         if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
 809                                 bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
 810                                         ia->ia_dstaddr.sin_len);
 811                         }
 812                         bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
 813                                 ia->ia_sockmask.sin_len);
 814
 815                         return (in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
 816                             ifp, td));
 817                 }
 818             }
 819         }
 820
 821         return (EOPNOTSUPP);    /*just for safety*/
 822 }
 823
 824 /*
 825  * Delete any existing route for an interface.
 826  */
 827 void
 828 in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia)
 829 {
 830
 831         in_scrubprefix(ia);
 832 }
 833
 834 /*
 835  * Initialize an interface's internet address
 836  * and routing table entry.
 837  */
 838 static int
 839 in_ifinit(struct ifnet *ifp, struct in_ifaddr *ia, struct sockaddr_in *sin,
 840     int scrub)
 841 {
 842         register u_long i = ntohl(sin->sin_addr.s_addr);
 843         struct sockaddr_in oldaddr;
 844         int s = splimp(), flags = RTF_UP, error = 0;
 845
 846         oldaddr = ia->ia_addr;
 847         if (oldaddr.sin_family == AF_INET)
 848                 LIST_REMOVE(ia, ia_hash);
 849         ia->ia_addr = *sin;
 850         if (ia->ia_addr.sin_family == AF_INET) {
 851                 IN_IFADDR_WLOCK();
 852                 LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
 853                     ia, ia_hash);
 854                 IN_IFADDR_WUNLOCK();
 855         }
 856         /*
 857          * Give the interface a chance to initialize
 858          * if this is its first address,
 859          * and to validate the address if necessary.
 860          */
 861         if (ifp->if_ioctl != NULL) {
 862                 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
 863                 if (error) {
 864                         splx(s);
 865                         /* LIST_REMOVE(ia, ia_hash) is done in in_control */
 866                         ia->ia_addr = oldaddr;
 867                         IN_IFADDR_WLOCK();
 868                         if (ia->ia_addr.sin_family == AF_INET)
 869                                 LIST_INSERT_HEAD(INADDR_HASH(
 870                                     ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
 871                         else
 872                                 /*
 873                                  * If oldaddr family is not AF_INET (e.g.
 874                                  * interface has been just created) in_control
 875                                  * does not call LIST_REMOVE, and we end up
 876                                  * with bogus ia entries in hash
 877                                  */
 878                                 LIST_REMOVE(ia, ia_hash);
 879                         IN_IFADDR_WUNLOCK();
 880                         return (error);
 881                 }
 882         }
 883         splx(s);
 884         if (scrub) {
 885                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
 886                 in_ifscrub(ifp, ia);
 887                 ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
 888         }
 889         if (IN_CLASSA(i))
 890                 ia->ia_netmask = IN_CLASSA_NET;
 891         else if (IN_CLASSB(i))
 892                 ia->ia_netmask = IN_CLASSB_NET;
 893         else
 894                 ia->ia_netmask = IN_CLASSC_NET;
 895         /*
 896          * The subnet mask usually includes at least the standard network part,
 897          * but may may be smaller in the case of supernetting.
 898          * If it is set, we believe it.
 899          */
 900         if (ia->ia_subnetmask == 0) {
 901                 ia->ia_subnetmask = ia->ia_netmask;
 902                 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
 903         } else
 904                 ia->ia_netmask &= ia->ia_subnetmask;
 905         ia->ia_net = i & ia->ia_netmask;
 906         ia->ia_subnet = i & ia->ia_subnetmask;
 907         in_socktrim(&ia->ia_sockmask);
 908         /*
 909          * XXX: carp(4) does not have interface route
 910          */
 911         if (ifp->if_type == IFT_CARP)
 912                 return (0);
 913         /*
 914          * Add route for the network.
 915          */
 916         ia->ia_ifa.ifa_metric = ifp->if_metric;
 917         if (ifp->if_flags & IFF_BROADCAST) {
 918                 ia->ia_broadaddr.sin_addr.s_addr =
 919                         htonl(ia->ia_subnet | ~ia->ia_subnetmask);
 920                 ia->ia_netbroadcast.s_addr =
 921                         htonl(ia->ia_net | ~ ia->ia_netmask);
 922         } else if (ifp->if_flags & IFF_LOOPBACK) {
 923                 ia->ia_dstaddr = ia->ia_addr;
 924                 flags |= RTF_HOST;
 925         } else if (ifp->if_flags & IFF_POINTOPOINT) {
 926                 if (ia->ia_dstaddr.sin_family != AF_INET)
 927                         return (0);
 928                 flags |= RTF_HOST;
 929         }
 930         if ((error = in_addprefix(ia, flags)) != 0)
 931                 return (error);
 932
 933         if (ia->ia_addr.sin_addr.s_addr == INADDR_ANY)
 934                 return (0);
 935
 936         if (ifp->if_flags & IFF_POINTOPOINT) {
 937                 if (ia->ia_dstaddr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr)
 938                         return (0);
 939         }
 940
 941
 942         /*
 943          * add a loopback route to self
 944          */
 945         if (V_useloopback && !(ifp->if_flags & IFF_LOOPBACK)) {
 946                 struct route ia_ro;
 947
 948                 bzero(&ia_ro, sizeof(ia_ro));
 949                 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = ia->ia_addr;
 950                 rtalloc_ign_fib(&ia_ro, 0, 0);
 951                 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
 952                     (ia_ro.ro_rt->rt_ifp == V_loif)) {
 953                         RT_LOCK(ia_ro.ro_rt);
 954                         RT_ADDREF(ia_ro.ro_rt);
 955                         RTFREE_LOCKED(ia_ro.ro_rt);
 956                 } else
 957                         error = ifa_add_loopback_route((struct ifaddr *)ia,
 958                                        (struct sockaddr *)&ia->ia_addr);
 959                 if (error == 0)
 960                         ia->ia_flags |= IFA_RTSELF;
 961                 if (ia_ro.ro_rt != NULL)
 962                         RTFREE(ia_ro.ro_rt);
 963         }
 964
 965         return (error);
 966 }
 967
 968 #define rtinitflags(x) \
 969         ((((x)->ia_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) != 0) \
 970             ? RTF_HOST : 0)
 971
 972 /*
 973  * Generate a routing message when inserting or deleting
 974  * an interface address alias.
 975  */
 976 static void in_addralias_rtmsg(int cmd, struct in_addr *prefix,
 977     struct in_ifaddr *target)
 978 {
 979         struct route pfx_ro;
 980         struct sockaddr_in *pfx_addr;
 981         struct rtentry msg_rt;
 982
 983         /* QL: XXX
 984          * This is a bit questionable because there is no
 985          * additional route entry added/deleted for an address
 986          * alias. Therefore this route report is inaccurate.
 987          */
 988         bzero(&pfx_ro, sizeof(pfx_ro));
 989         pfx_addr = (struct sockaddr_in *)(&pfx_ro.ro_dst);
 990         pfx_addr->sin_len = sizeof(*pfx_addr);
 991         pfx_addr->sin_family = AF_INET;
 992         pfx_addr->sin_addr = *prefix;
 993         rtalloc_ign_fib(&pfx_ro, 0, 0);
 994         if (pfx_ro.ro_rt != NULL) {
 995                 msg_rt = *pfx_ro.ro_rt;
 996
 997                 /* QL: XXX
 998                  * Point the gateway to the new interface
 999                  * address as if a new prefix route entry has
1000                  * been added through the new address alias.
1001                  * All other parts of the rtentry is accurate,
1002                  * e.g., rt_key, rt_mask, rt_ifp etc.
1003                  */
1004                 msg_rt.rt_gateway =
1005                         (struct sockaddr *)&target->ia_addr;
1006                 rt_newaddrmsg(cmd,
1007                               (struct ifaddr *)target,
1008                               0, &msg_rt);
1009                 RTFREE(pfx_ro.ro_rt);
1010         }
1011         return;
1012 }
1013
1014 /*
1015  * Check if we have a route for the given prefix already or add one accordingly.
1016  */
1017 static int
1018 in_addprefix(struct in_ifaddr *target, int flags)
1019 {
1020         struct in_ifaddr *ia;
1021         struct in_addr prefix, mask, p, m;
1022         int error;
1023
1024         if ((flags & RTF_HOST) != 0) {
1025                 prefix = target->ia_dstaddr.sin_addr;
1026                 mask.s_addr = 0;
1027         } else {
1028                 prefix = target->ia_addr.sin_addr;
1029                 mask = target->ia_sockmask.sin_addr;
1030                 prefix.s_addr &= mask.s_addr;
1031         }
1032
1033         IN_IFADDR_RLOCK();
1034         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1035                 if (rtinitflags(ia)) {
1036                         p = ia->ia_addr.sin_addr;
1037
1038                         if (prefix.s_addr != p.s_addr)
1039                                 continue;
1040                 } else {
1041                         p = ia->ia_addr.sin_addr;
1042                         m = ia->ia_sockmask.sin_addr;
1043                         p.s_addr &= m.s_addr;
1044
1045                         if (prefix.s_addr != p.s_addr ||
1046                             mask.s_addr != m.s_addr)
1047                                 continue;
1048                 }
1049
1050                 /*
1051                  * If we got a matching prefix route inserted by other
1052                  * interface address, we are done here.
1053                  */
1054                 if (ia->ia_flags & IFA_ROUTE) {
1055 #ifdef RADIX_MPATH
1056                         if (ia->ia_addr.sin_addr.s_addr ==
1057                             target->ia_addr.sin_addr.s_addr) {
1058                                 IN_IFADDR_RUNLOCK();
1059                                 return (EEXIST);
1060                         } else
1061                                 break;
1062 #endif
1063                         if (V_sameprefixcarponly &&
1064                             target->ia_ifp->if_type != IFT_CARP &&
1065                             ia->ia_ifp->if_type != IFT_CARP) {
1066                                 IN_IFADDR_RUNLOCK();
1067                                 return (EEXIST);
1068                         } else {
1069                                 in_addralias_rtmsg(RTM_ADD, &prefix, target);
1070                                 IN_IFADDR_RUNLOCK();
1071                                 return (0);
1072                         }
1073                 }
1074         }
1075         IN_IFADDR_RUNLOCK();
1076
1077         /*
1078          * No-one seem to have this prefix route, so we try to insert it.
1079          */
1080         error = rtinit(&target->ia_ifa, (int)RTM_ADD, flags);
1081         if (!error)
1082                 target->ia_flags |= IFA_ROUTE;
1083         return (error);
1084 }
1085
1086 extern void arp_ifscrub(struct ifnet *ifp, uint32_t addr);
1087
1088 /*
1089  * If there is no other address in the system that can serve a route to the
1090  * same prefix, remove the route.  Hand over the route to the new address
1091  * otherwise.
1092  */
1093 static int
1094 in_scrubprefix(struct in_ifaddr *target)
1095 {
1096         struct in_ifaddr *ia;
1097         struct in_addr prefix, mask, p;
1098         int error = 0;
1099         struct sockaddr_in prefix0, mask0;
1100
1101         /*
1102          * Remove the loopback route to the interface address.
1103          * The "useloopback" setting is not consulted because if the
1104          * user configures an interface address, turns off this
1105          * setting, and then tries to delete that interface address,
1106          * checking the current setting of "useloopback" would leave
1107          * that interface address loopback route untouched, which
1108          * would be wrong. Therefore the interface address loopback route
1109          * deletion is unconditional.
1110          */
1111         if ((target->ia_addr.sin_addr.s_addr != INADDR_ANY) &&
1112             !(target->ia_ifp->if_flags & IFF_LOOPBACK) &&
1113             (target->ia_flags & IFA_RTSELF)) {
1114                 struct route ia_ro;
1115                 int freeit = 0;
1116
1117                 bzero(&ia_ro, sizeof(ia_ro));
1118                 *((struct sockaddr_in *)(&ia_ro.ro_dst)) = target->ia_addr;
1119                 rtalloc_ign_fib(&ia_ro, 0, 0);
1120                 if ((ia_ro.ro_rt != NULL) && (ia_ro.ro_rt->rt_ifp != NULL) &&
1121                     (ia_ro.ro_rt->rt_ifp == V_loif)) {
1122                         RT_LOCK(ia_ro.ro_rt);
1123                         if (ia_ro.ro_rt->rt_refcnt <= 1)
1124                                 freeit = 1;
1125                         else
1126                                 RT_REMREF(ia_ro.ro_rt);
1127                         RTFREE_LOCKED(ia_ro.ro_rt);
1128                 }
1129                 if (freeit)
1130                         error = ifa_del_loopback_route((struct ifaddr *)target,
1131                                        (struct sockaddr *)&target->ia_addr);
1132                 if (error == 0)
1133                         target->ia_flags &= ~IFA_RTSELF;
1134                 /* remove arp cache */
1135                 arp_ifscrub(target->ia_ifp, IA_SIN(target)->sin_addr.s_addr);
1136         }
1137
1138         if (rtinitflags(target))
1139                 prefix = target->ia_dstaddr.sin_addr;
1140         else {
1141                 prefix = target->ia_addr.sin_addr;
1142                 mask = target->ia_sockmask.sin_addr;
1143                 prefix.s_addr &= mask.s_addr;
1144         }
1145
1146         if ((target->ia_flags & IFA_ROUTE) == 0) {
1147                 in_addralias_rtmsg(RTM_DELETE, &prefix, target);
1148                 return (0);
1149         }
1150
1151         IN_IFADDR_RLOCK();
1152         TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1153                 if (rtinitflags(ia))
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
1160                 if (prefix.s_addr != p.s_addr)
1161                         continue;
1162
1163                 /*
1164                  * If we got a matching prefix address, move IFA_ROUTE and
1165                  * the route itself to it.  Make sure that routing daemons
1166                  * get a heads-up.
1167                  *
1168                  * XXX: a special case for carp(4) interface - this should
1169                  *      be more generally specified as an interface that
1170                  *      doesn't support such action.
1171                  */
1172                 if ((ia->ia_flags & IFA_ROUTE) == 0
1173                     && (ia->ia_ifp->if_type != IFT_CARP)
1174                                                         ) {
1175                         IN_IFADDR_RUNLOCK();
1176                         rtinit(&(target->ia_ifa), (int)RTM_DELETE,
1177                             rtinitflags(target));
1178                         target->ia_flags &= ~IFA_ROUTE;
1179
1180                         error = rtinit(&ia->ia_ifa, (int)RTM_ADD,
1181                             rtinitflags(ia) | RTF_UP);
1182                         if (error == 0)
1183                                 ia->ia_flags |= IFA_ROUTE;
1184                         return (error);
1185                 }
1186         }
1187         IN_IFADDR_RUNLOCK();
1188
1189         /*
1190          * remove all L2 entries on the given prefix
1191          */
1192         bzero(&prefix0, sizeof(prefix0));
1193         prefix0.sin_len = sizeof(prefix0);
1194         prefix0.sin_family = AF_INET;
1195         prefix0.sin_addr.s_addr = target->ia_subnet;
1196         bzero(&mask0, sizeof(mask0));
1197         mask0.sin_len = sizeof(mask0);
1198         mask0.sin_family = AF_INET;
1199         mask0.sin_addr.s_addr = target->ia_subnetmask;
1200         lltable_prefix_free(AF_INET, (struct sockaddr *)&prefix0,
1201                             (struct sockaddr *)&mask0);
1202
1203         /*
1204          * As no-one seem to have this prefix, we can remove the route.
1205          */
1206         rtinit(&(target->ia_ifa), (int)RTM_DELETE, rtinitflags(target));
1207         target->ia_flags &= ~IFA_ROUTE;
1208         return (0);
1209 }
1210
1211 #undef rtinitflags
1212
1213 /*
1214  * Return 1 if the address might be a local broadcast address.
1215  */
1216 int
1217 in_broadcast(struct in_addr in, struct ifnet *ifp)
1218 {
1219         register struct ifaddr *ifa;
1220         u_long t;
1221
1222         if (in.s_addr == INADDR_BROADCAST ||
1223             in.s_addr == INADDR_ANY)
1224                 return (1);
1225         if ((ifp->if_flags & IFF_BROADCAST) == 0)
1226                 return (0);
1227         t = ntohl(in.s_addr);
1228         /*
1229          * Look through the list of addresses for a match
1230          * with a broadcast address.
1231          */
1232 #define ia ((struct in_ifaddr *)ifa)
1233         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
1234                 if (ifa->ifa_addr->sa_family == AF_INET &&
1235                     (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
1236                      in.s_addr == ia->ia_netbroadcast.s_addr ||
1237                      /*
1238                       * Check for old-style (host 0) broadcast.
1239                       */
1240                      t == ia->ia_subnet || t == ia->ia_net) &&
1241                      /*
1242                       * Check for an all one subnetmask. These
1243                       * only exist when an interface gets a secondary
1244                       * address.
1245                       */
1246                      ia->ia_subnetmask != (u_long)0xffffffff)
1247                             return (1);
1248         return (0);
1249 #undef ia
1250 }
1251
1252 /*
1253  * On interface removal, clean up IPv4 data structures hung off of the ifnet.
1254  */
1255 void
1256 in_ifdetach(struct ifnet *ifp)
1257 {
1258
1259         in_pcbpurgeif0(&V_ripcbinfo, ifp);
1260         in_pcbpurgeif0(&V_udbinfo, ifp);
1261         in_purgemaddrs(ifp);
1262 }
1263
1264 /*
1265  * Delete all IPv4 multicast address records, and associated link-layer
1266  * multicast address records, associated with ifp.
1267  * XXX It looks like domifdetach runs AFTER the link layer cleanup.
1268  * XXX This should not race with ifma_protospec being set during
1269  * a new allocation, if it does, we have bigger problems.
1270  */
1271 static void
1272 in_purgemaddrs(struct ifnet *ifp)
1273 {
1274         LIST_HEAD(,in_multi) purgeinms;
1275         struct in_multi         *inm, *tinm;
1276         struct ifmultiaddr      *ifma;
1277
1278         LIST_INIT(&purgeinms);
1279         IN_MULTI_LOCK();
1280
1281         /*
1282          * Extract list of in_multi associated with the detaching ifp
1283          * which the PF_INET layer is about to release.
1284          * We need to do this as IF_ADDR_LOCK() may be re-acquired
1285          * by code further down.
1286          */
1287         IF_ADDR_LOCK(ifp);
1288         TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1289                 if (ifma->ifma_addr->sa_family != AF_INET ||
1290                     ifma->ifma_protospec == NULL)
1291                         continue;
1292 #if 0
1293                 KASSERT(ifma->ifma_protospec != NULL,
1294                     ("%s: ifma_protospec is NULL", __func__));
1295 #endif
1296                 inm = (struct in_multi *)ifma->ifma_protospec;
1297                 LIST_INSERT_HEAD(&purgeinms, inm, inm_link);
1298         }
1299         IF_ADDR_UNLOCK(ifp);
1300
1301         LIST_FOREACH_SAFE(inm, &purgeinms, inm_link, tinm) {
1302                 LIST_REMOVE(inm, inm_link);
1303                 inm_release_locked(inm);
1304         }
1305         igmp_ifdetach(ifp);
1306
1307         IN_MULTI_UNLOCK();
1308 }
1309
1310 #include <net/if_dl.h>
1311 #include <netinet/if_ether.h>
1312
1313 struct in_llentry {
1314         struct llentry          base;
1315         struct sockaddr_in      l3_addr4;
1316 };
1317
1318 static struct llentry *
1319 in_lltable_new(const struct sockaddr *l3addr, u_int flags)
1320 {
1321         struct in_llentry *lle;
1322
1323         lle = malloc(sizeof(struct in_llentry), M_LLTABLE, M_DONTWAIT | M_ZERO);
1324         if (lle == NULL)                /* NB: caller generates msg */
1325                 return NULL;
1326
1327         callout_init(&lle->base.la_timer, CALLOUT_MPSAFE);
1328         /*
1329          * For IPv4 this will trigger "arpresolve" to generate
1330          * an ARP request.
1331          */
1332         lle->base.la_expire = time_second; /* mark expired */
1333         lle->l3_addr4 = *(const struct sockaddr_in *)l3addr;
1334         lle->base.lle_refcnt = 1;
1335         LLE_LOCK_INIT(&lle->base);
1336         return &lle->base;
1337 }
1338
1339 /*
1340  * Deletes an address from the address table.
1341  * This function is called by the timer functions
1342  * such as arptimer() and nd6_llinfo_timer(), and
1343  * the caller does the locking.
1344  */
1345 static void
1346 in_lltable_free(struct lltable *llt, struct llentry *lle)
1347 {
1348         LLE_WUNLOCK(lle);
1349         LLE_LOCK_DESTROY(lle);
1350         free(lle, M_LLTABLE);
1351 }
1352
1353
1354 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m)       (                       \
1355             (((ntohl((d)->sin_addr.s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 )
1356
1357 static void
1358 in_lltable_prefix_free(struct lltable *llt,
1359                        const struct sockaddr *prefix,
1360                        const struct sockaddr *mask)
1361 {
1362         const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
1363         const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
1364         struct llentry *lle, *next;
1365         register int i;
1366
1367         for (i=0; i < LLTBL_HASHTBL_SIZE; i++) {
1368                 LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
1369
1370                         if (IN_ARE_MASKED_ADDR_EQUAL((struct sockaddr_in *)L3_ADDR(lle),
1371                                                      pfx, msk)) {
1372                                 int canceled;
1373
1374                                 canceled = callout_drain(&lle->la_timer);
1375                                 LLE_WLOCK(lle);
1376                                 if (canceled)
1377                                         LLE_REMREF(lle);
1378                                 llentry_free(lle);
1379                         }
1380                 }
1381         }
1382 }
1383
1384
1385 static int
1386 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
1387 {
1388         struct rtentry *rt;
1389
1390         KASSERT(l3addr->sa_family == AF_INET,
1391             ("sin_family %d", l3addr->sa_family));
1392
1393         /* XXX rtalloc1 should take a const param */
1394         rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
1395         if (rt == NULL || (!(flags & LLE_PUB) &&
1396                            ((rt->rt_flags & RTF_GATEWAY) ||
1397                             (rt->rt_ifp != ifp)))) {
1398 #ifdef DIAGNOSTIC
1399                 log(LOG_INFO, "IPv4 address: \"%s\" is not on the network\n",
1400                     inet_ntoa(((const struct sockaddr_in *)l3addr)->sin_addr));
1401 #endif
1402                 if (rt != NULL)
1403                         RTFREE_LOCKED(rt);
1404                 return (EINVAL);
1405         }
1406         RTFREE_LOCKED(rt);
1407         return 0;
1408 }
1409
1410 /*
1411  * Return NULL if not found or marked for deletion.
1412  * If found return lle read locked.
1413  */
1414 static struct llentry *
1415 in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
1416 {
1417         const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
1418         struct ifnet *ifp = llt->llt_ifp;
1419         struct llentry *lle;
1420         struct llentries *lleh;
1421         u_int hashkey;
1422
1423         IF_AFDATA_LOCK_ASSERT(ifp);
1424         KASSERT(l3addr->sa_family == AF_INET,
1425             ("sin_family %d", l3addr->sa_family));
1426
1427         hashkey = sin->sin_addr.s_addr;
1428         lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
1429         LIST_FOREACH(lle, lleh, lle_next) {
1430                 struct sockaddr_in *sa2 = (struct sockaddr_in *)L3_ADDR(lle);
1431                 if (lle->la_flags & LLE_DELETED)
1432                         continue;
1433                 if (sa2->sin_addr.s_addr == sin->sin_addr.s_addr)
1434                         break;
1435         }
1436         if (lle == NULL) {
1437 #ifdef DIAGNOSTIC
1438                 if (flags & LLE_DELETE)
1439                         log(LOG_INFO, "interface address is missing from cache = %p  in delete\n", lle);
1440 #endif
1441                 if (!(flags & LLE_CREATE))
1442                         return (NULL);
1443                 /*
1444                  * A route that covers the given address must have
1445                  * been installed 1st because we are doing a resolution,
1446                  * verify this.
1447                  */
1448                 if (!(flags & LLE_IFADDR) &&
1449                     in_lltable_rtcheck(ifp, flags, l3addr) != 0)
1450                         goto done;
1451
1452                 lle = in_lltable_new(l3addr, flags);
1453                 if (lle == NULL) {
1454                         log(LOG_INFO, "lla_lookup: new lle malloc failed\n");
1455                         goto done;
1456                 }
1457                 lle->la_flags = flags & ~LLE_CREATE;
1458                 if ((flags & (LLE_CREATE | LLE_IFADDR)) == (LLE_CREATE | LLE_IFADDR)) {
1459                         bcopy(IF_LLADDR(ifp), &lle->ll_addr, ifp->if_addrlen);
1460                         lle->la_flags |= (LLE_VALID | LLE_STATIC);
1461                 }
1462
1463                 lle->lle_tbl  = llt;
1464                 lle->lle_head = lleh;
1465                 LIST_INSERT_HEAD(lleh, lle, lle_next);
1466         } else if (flags & LLE_DELETE) {
1467                 if (!(lle->la_flags & LLE_IFADDR) || (flags & LLE_IFADDR)) {
1468                         LLE_WLOCK(lle);
1469                         lle->la_flags = LLE_DELETED;
1470                         LLE_WUNLOCK(lle);
1471 #ifdef DIAGNOSTIC
1472                         log(LOG_INFO, "ifaddr cache = %p  is deleted\n", lle);
1473 #endif
1474                 }
1475                 lle = (void *)-1;
1476
1477         }
1478         if (LLE_IS_VALID(lle)) {
1479                 if (flags & LLE_EXCLUSIVE)
1480                         LLE_WLOCK(lle);
1481                 else
1482                         LLE_RLOCK(lle);
1483         }
1484 done:
1485         return (lle);
1486 }
1487
1488 static int
1489 in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
1490 {
1491 #define SIN(lle)        ((struct sockaddr_in *) L3_ADDR(lle))
1492         struct ifnet *ifp = llt->llt_ifp;
1493         struct llentry *lle;
1494         /* XXX stack use */
1495         struct {
1496                 struct rt_msghdr        rtm;
1497                 struct sockaddr_inarp   sin;
1498                 struct sockaddr_dl      sdl;
1499         } arpc;
1500         int error, i;
1501
1502         LLTABLE_LOCK_ASSERT();
1503
1504         error = 0;
1505         for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
1506                 LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
1507                         struct sockaddr_dl *sdl;
1508
1509                         /* skip deleted entries */
1510                         if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
1511                                 continue;
1512                         /* Skip if jailed and not a valid IP of the prison. */
1513                         if (prison_if(wr->td->td_ucred, L3_ADDR(lle)) != 0)
1514                                 continue;
1515                         /*
1516                          * produce a msg made of:
1517                          *  struct rt_msghdr;
1518                          *  struct sockaddr_inarp; (IPv4)
1519                          *  struct sockaddr_dl;
1520                          */
1521                         bzero(&arpc, sizeof(arpc));
1522                         arpc.rtm.rtm_msglen = sizeof(arpc);
1523                         arpc.rtm.rtm_version = RTM_VERSION;
1524                         arpc.rtm.rtm_type = RTM_GET;
1525                         arpc.rtm.rtm_flags = RTF_UP;
1526                         arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;
1527                         arpc.sin.sin_family = AF_INET;
1528                         arpc.sin.sin_len = sizeof(arpc.sin);
1529                         arpc.sin.sin_addr.s_addr = SIN(lle)->sin_addr.s_addr;
1530
1531                         /* publish */
1532                         if (lle->la_flags & LLE_PUB) {
1533                                 arpc.rtm.rtm_flags |= RTF_ANNOUNCE;
1534                                 /* proxy only */
1535                                 if (lle->la_flags & LLE_PROXY)
1536                                         arpc.sin.sin_other = SIN_PROXY;
1537                         }
1538
1539                         sdl = &arpc.sdl;
1540                         sdl->sdl_family = AF_LINK;
1541                         sdl->sdl_len = sizeof(*sdl);
1542                         sdl->sdl_index = ifp->if_index;
1543                         sdl->sdl_type = ifp->if_type;
1544                         if ((lle->la_flags & LLE_VALID) == LLE_VALID) {
1545                                 sdl->sdl_alen = ifp->if_addrlen;
1546                                 bcopy(&lle->ll_addr, LLADDR(sdl), ifp->if_addrlen);
1547                         } else {
1548                                 sdl->sdl_alen = 0;
1549                                 bzero(LLADDR(sdl), ifp->if_addrlen);
1550                         }
1551
1552                         arpc.rtm.rtm_rmx.rmx_expire =
1553                             lle->la_flags & LLE_STATIC ? 0 : lle->la_expire;
1554                         arpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA);
1555                         if (lle->la_flags & LLE_STATIC)
1556                                 arpc.rtm.rtm_flags |= RTF_STATIC;
1557                         arpc.rtm.rtm_index = ifp->if_index;
1558                         error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
1559                         if (error)
1560                                 break;
1561                 }
1562         }
1563         return error;
1564 #undef SIN
1565 }
1566
1567 void *
1568 in_domifattach(struct ifnet *ifp)
1569 {
1570         struct in_ifinfo *ii;
1571         struct lltable *llt;
1572
1573         ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO);
1574
1575         llt = lltable_init(ifp, AF_INET);
1576         if (llt != NULL) {
1577                 llt->llt_new = in_lltable_new;
1578                 llt->llt_free = in_lltable_free;
1579                 llt->llt_prefix_free = in_lltable_prefix_free;
1580                 llt->llt_rtcheck = in_lltable_rtcheck;
1581                 llt->llt_lookup = in_lltable_lookup;
1582                 llt->llt_dump = in_lltable_dump;
1583         }
1584         ii->ii_llt = llt;
1585
1586         ii->ii_igmp = igmp_domifattach(ifp);
1587
1588         return ii;
1589 }
1590
1591 void
1592 in_domifdetach(struct ifnet *ifp, void *aux)
1593 {
1594         struct in_ifinfo *ii = (struct in_ifinfo *)aux;
1595
1596         igmp_domifdetach(ifp);
1597         lltable_free(ii->ii_llt);
1598         free(ii, M_IFADDR);
1599 }