zebra/connected.c

   1 /*
   2  * Address linked list routine.
   3  * Copyright (C) 1997, 98 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <zebra.h>
  23
  24 #include "prefix.h"
  25 #include "linklist.h"
  26 #include "if.h"
  27 #include "table.h"
  28 #include "rib.h"
  29 #include "table.h"
  30 #include "log.h"
  31 #include "memory.h"
  32
  33 #include "vty.h"
  34 #include "zebra/debug.h"
  35 #include "zebra/zserv.h"
  36 #include "zebra/redistribute.h"
  37 #include "zebra/interface.h"
  38 #include "zebra/connected.h"
  39 #include "zebra/rtadv.h"
  40 #include "zebra/zebra_mpls.h"
  41 #include "zebra/zebra_errors.h"
  42 #include "zebra/zebra_router.h"
  43
  44 /* communicate the withdrawal of a connected address */
  45 static void connected_withdraw(struct connected *ifc)
  46 {
  47         if (!ifc)
  48                 return;
  49
  50         /* Update interface address information to protocol daemon. */
  51         if (CHECK_FLAG(ifc->conf, ZEBRA_IFC_REAL)) {
  52                 zebra_interface_address_delete_update(ifc->ifp, ifc);
  53
  54                 if (ifc->address->family == AF_INET)
  55                         if_subnet_delete(ifc->ifp, ifc);
  56
  57                 connected_down(ifc->ifp, ifc);
  58
  59                 UNSET_FLAG(ifc->conf, ZEBRA_IFC_REAL);
  60         }
  61
  62         /* The address is not in the kernel anymore, so clear the flag */
  63         UNSET_FLAG(ifc->conf, ZEBRA_IFC_QUEUED);
  64
  65         if (!CHECK_FLAG(ifc->conf, ZEBRA_IFC_CONFIGURED)) {
  66                 listnode_delete(ifc->ifp->connected, ifc);
  67                 connected_free(&ifc);
  68         }
  69 }
  70
  71 static void connected_announce(struct interface *ifp, struct connected *ifc)
  72 {
  73         if (!ifc)
  74                 return;
  75
  76         if (!if_is_loopback(ifp) && ifc->address->family == AF_INET) {
  77                 if (ifc->address->prefixlen == IPV4_MAX_BITLEN)
  78                         SET_FLAG(ifc->flags, ZEBRA_IFA_UNNUMBERED);
  79                 else
  80                         UNSET_FLAG(ifc->flags, ZEBRA_IFA_UNNUMBERED);
  81         }
  82
  83         listnode_add(ifp->connected, ifc);
  84
  85         /* Update interface address information to protocol daemon. */
  86         if (ifc->address->family == AF_INET)
  87                 if_subnet_add(ifp, ifc);
  88
  89         zebra_interface_address_add_update(ifp, ifc);
  90
  91         if (if_is_operative(ifp)) {
  92                 connected_up(ifp, ifc);
  93         }
  94 }
  95
  96 /* If same interface address is already exist... */
  97 struct connected *connected_check(struct interface *ifp,
  98                                   union prefixconstptr pu)
  99 {
 100         const struct prefix *p = pu.p;
 101         struct connected *ifc;
 102         struct listnode *node;
 103
 104         for (ALL_LIST_ELEMENTS_RO(ifp->connected, node, ifc))
 105                 if (prefix_same(ifc->address, p))
 106                         return ifc;
 107
 108         return NULL;
 109 }
 110
 111 /* same, but with peer address */
 112 struct connected *connected_check_ptp(struct interface *ifp,
 113                                       union prefixconstptr pu,
 114                                       union prefixconstptr du)
 115 {
 116         const struct prefix *p = pu.p;
 117         const struct prefix *d = du.p;
 118         struct connected *ifc;
 119         struct listnode *node;
 120
 121         for (ALL_LIST_ELEMENTS_RO(ifp->connected, node, ifc)) {
 122                 if (!prefix_same(ifc->address, p))
 123                         continue;
 124                 if (!CONNECTED_PEER(ifc) && !d)
 125                         return ifc;
 126                 if (CONNECTED_PEER(ifc) && d
 127                     && prefix_same(ifc->destination, d))
 128                         return ifc;
 129         }
 130
 131         return NULL;
 132 }
 133
 134 /* Check if two ifc's describe the same address in the same state */
 135 static int connected_same(struct connected *ifc1, struct connected *ifc2)
 136 {
 137         if (ifc1->ifp != ifc2->ifp)
 138                 return 0;
 139
 140         if (ifc1->flags != ifc2->flags)
 141                 return 0;
 142
 143         if (ifc1->conf != ifc2->conf)
 144                 return 0;
 145
 146         if (ifc1->destination)
 147                 if (!ifc2->destination)
 148                         return 0;
 149         if (ifc2->destination)
 150                 if (!ifc1->destination)
 151                         return 0;
 152
 153         if (ifc1->destination && ifc2->destination)
 154                 if (!prefix_same(ifc1->destination, ifc2->destination))
 155                         return 0;
 156
 157         return 1;
 158 }
 159
 160 /* Handle changes to addresses and send the neccesary announcements
 161  * to clients. */
 162 static void connected_update(struct interface *ifp, struct connected *ifc)
 163 {
 164         struct connected *current;
 165
 166         /* Check same connected route. */
 167         current = connected_check_ptp(ifp, ifc->address, ifc->destination);
 168         if (current) {
 169                 if (CHECK_FLAG(current->conf, ZEBRA_IFC_CONFIGURED))
 170                         SET_FLAG(ifc->conf, ZEBRA_IFC_CONFIGURED);
 171
 172                 /* Avoid spurious withdraws, this might be just the kernel
 173                  * 'reflecting'
 174                  * back an address we have already added.
 175                  */
 176                 if (connected_same(current, ifc)) {
 177                         /* nothing to do */
 178                         connected_free(&ifc);
 179                         return;
 180                 }
 181
 182                 /* Clear the configured flag on the old ifc, so it will be freed
 183                  * by
 184                  * connected withdraw. */
 185                 UNSET_FLAG(current->conf, ZEBRA_IFC_CONFIGURED);
 186                 connected_withdraw(
 187                         current); /* implicit withdraw - freebsd does this */
 188         }
 189
 190         /* If the connected is new or has changed, announce it, if it is usable
 191          */
 192         if (CHECK_FLAG(ifc->conf, ZEBRA_IFC_REAL))
 193                 connected_announce(ifp, ifc);
 194 }
 195
 196 /* Called from if_up(). */
 197 void connected_up(struct interface *ifp, struct connected *ifc)
 198 {
 199         afi_t afi;
 200         struct prefix p;
 201         struct nexthop nh = {
 202                 .type = NEXTHOP_TYPE_IFINDEX,
 203                 .ifindex = ifp->ifindex,
 204                 .vrf_id = ifp->vrf->vrf_id,
 205         };
 206         struct zebra_vrf *zvrf;
 207         uint32_t metric;
 208         uint32_t flags = 0;
 209         uint32_t count = 0;
 210         struct listnode *cnode;
 211         struct connected *c;
 212
 213         zvrf = ifp->vrf->info;
 214         if (!zvrf) {
 215                 flog_err(
 216                         EC_ZEBRA_VRF_NOT_FOUND,
 217                         "%s: Received Up for interface but no associated zvrf: %s(%d)",
 218                         __func__, ifp->vrf->name, ifp->vrf->vrf_id);
 219                 return;
 220         }
 221         if (!CHECK_FLAG(ifc->conf, ZEBRA_IFC_REAL))
 222                 return;
 223
 224         /* Ensure 'down' flag is cleared */
 225         UNSET_FLAG(ifc->conf, ZEBRA_IFC_DOWN);
 226
 227         prefix_copy(&p, CONNECTED_PREFIX(ifc));
 228
 229         /* Apply mask to the network. */
 230         apply_mask(&p);
 231
 232         afi = family2afi(p.family);
 233
 234         switch (afi) {
 235         case AFI_IP:
 236                 /*
 237                  * In case of connected address is 0.0.0.0/0 we treat it tunnel
 238                  * address.
 239                  */
 240                 if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
 241                         return;
 242                 break;
 243         case AFI_IP6:
 244 #ifndef GNU_LINUX
 245                 /* XXX: It is already done by rib_bogus_ipv6 within rib_add */
 246                 if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
 247                         return;
 248 #endif
 249                 break;
 250         default:
 251                 flog_warn(EC_ZEBRA_CONNECTED_AFI_UNKNOWN,
 252                           "Received unknown AFI: %s", afi2str(afi));
 253                 return;
 254                 break;
 255         }
 256
 257         metric = (ifc->metric < (uint32_t)METRIC_MAX) ?
 258                                 ifc->metric : ifp->metric;
 259
 260         /*
 261          * Since we are hand creating the connected routes
 262          * in our main routing table, *if* we are working
 263          * in an offloaded environment then we need to
 264          * pretend like the route is offloaded so everything
 265          * else will work
 266          */
 267         if (zrouter.asic_offloaded)
 268                 flags |= ZEBRA_FLAG_OFFLOADED;
 269
 270         /*
 271          * It's possible to add the same network and mask
 272          * to an interface over and over.  This would
 273          * result in an equivalent number of connected
 274          * routes.  Just add one connected route in
 275          * for all the addresses on an interface that
 276          * resolve to the same network and mask
 277          */
 278         for (ALL_LIST_ELEMENTS_RO(ifp->connected, cnode, c)) {
 279                 struct prefix cp;
 280
 281                 prefix_copy(&cp, CONNECTED_PREFIX(c));
 282                 apply_mask(&cp);
 283
 284                 if (prefix_same(&cp, &p) &&
 285                     !CHECK_FLAG(c->conf, ZEBRA_IFC_DOWN))
 286                         count++;
 287
 288                 if (count >= 2)
 289                         return;
 290         }
 291
 292         rib_add(afi, SAFI_UNICAST, zvrf->vrf->vrf_id, ZEBRA_ROUTE_CONNECT, 0,
 293                 flags, &p, NULL, &nh, 0, zvrf->table_id, metric, 0, 0, 0,
 294                 false);
 295
 296         rib_add(afi, SAFI_MULTICAST, zvrf->vrf->vrf_id, ZEBRA_ROUTE_CONNECT, 0,
 297                 flags, &p, NULL, &nh, 0, zvrf->table_id, metric, 0, 0, 0,
 298                 false);
 299
 300         /* Schedule LSP forwarding entries for processing, if appropriate. */
 301         if (zvrf->vrf->vrf_id == VRF_DEFAULT) {
 302                 if (IS_ZEBRA_DEBUG_MPLS)
 303                         zlog_debug(
 304                                 "%u: IF %s IP %pFX address add/up, scheduling MPLS processing",
 305                                 zvrf->vrf->vrf_id, ifp->name, &p);
 306                 mpls_mark_lsps_for_processing(zvrf, &p);
 307         }
 308 }
 309
 310 /* Add connected IPv4 route to the interface. */
 311 void connected_add_ipv4(struct interface *ifp, int flags,
 312                         const struct in_addr *addr, uint16_t prefixlen,
 313                         const struct in_addr *dest, const char *label,
 314                         uint32_t metric)
 315 {
 316         struct prefix_ipv4 *p;
 317         struct connected *ifc;
 318
 319         if (ipv4_martian(addr))
 320                 return;
 321
 322         /* Make connected structure. */
 323         ifc = connected_new();
 324         ifc->ifp = ifp;
 325         ifc->flags = flags;
 326         ifc->metric = metric;
 327         /* If we get a notification from the kernel,
 328          * we can safely assume the address is known to the kernel */
 329         SET_FLAG(ifc->conf, ZEBRA_IFC_QUEUED);
 330         if (!if_is_operative(ifp))
 331                 SET_FLAG(ifc->conf, ZEBRA_IFC_DOWN);
 332
 333         /* Allocate new connected address. */
 334         p = prefix_ipv4_new();
 335         p->family = AF_INET;
 336         p->prefix = *addr;
 337         p->prefixlen =
 338                 CHECK_FLAG(flags, ZEBRA_IFA_PEER) ? IPV4_MAX_BITLEN : prefixlen;
 339         ifc->address = (struct prefix *)p;
 340
 341         /* If there is a peer address. */
 342         if (CONNECTED_PEER(ifc)) {
 343                 /* validate the destination address */
 344                 if (dest) {
 345                         p = prefix_ipv4_new();
 346                         p->family = AF_INET;
 347                         p->prefix = *dest;
 348                         p->prefixlen = prefixlen;
 349                         ifc->destination = (struct prefix *)p;
 350
 351                         if (IPV4_ADDR_SAME(addr, dest))
 352                                 flog_warn(
 353                                         EC_ZEBRA_IFACE_SAME_LOCAL_AS_PEER,
 354                                         "interface %s has same local and peer address %pI4, routing protocols may malfunction",
 355                                         ifp->name, addr);
 356                 } else {
 357                         zlog_debug(
 358                                 "%s called for interface %s with peer flag set, but no peer address supplied",
 359                                 __func__, ifp->name);
 360                         UNSET_FLAG(ifc->flags, ZEBRA_IFA_PEER);
 361                 }
 362         }
 363
 364         /* no destination address was supplied */
 365         if (!dest && (prefixlen == IPV4_MAX_BITLEN) && if_is_pointopoint(ifp))
 366                 zlog_debug(
 367                         "PtP interface %s with addr %pI4/%d needs a peer address",
 368                         ifp->name, addr, prefixlen);
 369
 370         /* Label of this address. */
 371         if (label)
 372                 ifc->label = XSTRDUP(MTYPE_CONNECTED_LABEL, label);
 373
 374         /* For all that I know an IPv4 address is always ready when we receive
 375          * the notification. So it should be safe to set the REAL flag here. */
 376         SET_FLAG(ifc->conf, ZEBRA_IFC_REAL);
 377
 378         connected_update(ifp, ifc);
 379 }
 380
 381 void connected_down(struct interface *ifp, struct connected *ifc)
 382 {
 383         afi_t afi;
 384         struct prefix p;
 385         struct nexthop nh = {
 386                 .type = NEXTHOP_TYPE_IFINDEX,
 387                 .ifindex = ifp->ifindex,
 388                 .vrf_id = ifp->vrf->vrf_id,
 389         };
 390         struct zebra_vrf *zvrf;
 391         uint32_t count = 0;
 392         struct listnode *cnode;
 393         struct connected *c;
 394
 395         zvrf = ifp->vrf->info;
 396         if (!zvrf) {
 397                 flog_err(
 398                         EC_ZEBRA_VRF_NOT_FOUND,
 399                         "%s: Received Down for interface but no associated zvrf: %s(%d)",
 400                         __func__, ifp->vrf->name, ifp->vrf->vrf_id);
 401                 return;
 402         }
 403
 404         if (!CHECK_FLAG(ifc->conf, ZEBRA_IFC_REAL))
 405                 return;
 406
 407         /* Skip if we've already done this; this can happen if we have a
 408          * config change that takes an interface down, then we receive kernel
 409          * notifications about the downed interface and its addresses.
 410          */
 411         if (CHECK_FLAG(ifc->conf, ZEBRA_IFC_DOWN)) {
 412                 if (IS_ZEBRA_DEBUG_RIB)
 413                         zlog_debug("%s: ifc %p, %pFX already DOWN",
 414                                    __func__, ifc, ifc->address);
 415                 return;
 416         }
 417
 418         prefix_copy(&p, CONNECTED_PREFIX(ifc));
 419
 420         /* Apply mask to the network. */
 421         apply_mask(&p);
 422
 423         afi = family2afi(p.family);
 424
 425         switch (afi) {
 426         case AFI_IP:
 427                 /*
 428                  * In case of connected address is 0.0.0.0/0 we treat it tunnel
 429                  *  address.
 430                  */
 431                 if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
 432                         return;
 433                 break;
 434         case AFI_IP6:
 435                 if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
 436                         return;
 437                 break;
 438         default:
 439                 zlog_warn("Unknown AFI: %s", afi2str(afi));
 440                 break;
 441         }
 442
 443         /* Mark the address as 'down' */
 444         SET_FLAG(ifc->conf, ZEBRA_IFC_DOWN);
 445
 446         /*
 447          * It's possible to have X number of addresses
 448          * on a interface that all resolve to the same
 449          * network and mask.  Find them and just
 450          * allow the deletion when are removing the last
 451          * one.
 452          */
 453         for (ALL_LIST_ELEMENTS_RO(ifp->connected, cnode, c)) {
 454                 struct prefix cp;
 455
 456                 prefix_copy(&cp, CONNECTED_PREFIX(c));
 457                 apply_mask(&cp);
 458
 459                 if (prefix_same(&p, &cp) &&
 460                     !CHECK_FLAG(c->conf, ZEBRA_IFC_DOWN))
 461                         count++;
 462
 463                 if (count >= 1)
 464                         return;
 465         }
 466
 467         /*
 468          * Same logic as for connected_up(): push the changes into the
 469          * head.
 470          */
 471         rib_delete(afi, SAFI_UNICAST, zvrf->vrf->vrf_id, ZEBRA_ROUTE_CONNECT, 0,
 472                    0, &p, NULL, &nh, 0, zvrf->table_id, 0, 0, false);
 473
 474         rib_delete(afi, SAFI_MULTICAST, zvrf->vrf->vrf_id, ZEBRA_ROUTE_CONNECT,
 475                    0, 0, &p, NULL, &nh, 0, zvrf->table_id, 0, 0, false);
 476
 477         /* Schedule LSP forwarding entries for processing, if appropriate. */
 478         if (zvrf->vrf->vrf_id == VRF_DEFAULT) {
 479                 if (IS_ZEBRA_DEBUG_MPLS)
 480                         zlog_debug(
 481                                 "%u: IF %s IP %pFX address down, scheduling MPLS processing",
 482                                 zvrf->vrf->vrf_id, ifp->name, &p);
 483                 mpls_mark_lsps_for_processing(zvrf, &p);
 484         }
 485 }
 486
 487 static void connected_delete_helper(struct connected *ifc, struct prefix *p)
 488 {
 489         struct interface *ifp;
 490
 491         if (!ifc)
 492                 return;
 493         ifp = ifc->ifp;
 494
 495         connected_withdraw(ifc);
 496
 497         /* Schedule LSP forwarding entries for processing, if appropriate. */
 498         if (ifp->vrf->vrf_id == VRF_DEFAULT) {
 499                 if (IS_ZEBRA_DEBUG_MPLS)
 500                         zlog_debug(
 501                                 "%u: IF %s IP %pFX address delete, scheduling MPLS processing",
 502                                 ifp->vrf->vrf_id, ifp->name, p);
 503                 mpls_mark_lsps_for_processing(ifp->vrf->info, p);
 504         }
 505 }
 506
 507 /* Delete connected IPv4 route to the interface. */
 508 void connected_delete_ipv4(struct interface *ifp, int flags,
 509                            const struct in_addr *addr, uint16_t prefixlen,
 510                            const struct in_addr *dest)
 511 {
 512         struct prefix p, d;
 513         struct connected *ifc;
 514
 515         memset(&p, 0, sizeof(p));
 516         p.family = AF_INET;
 517         p.u.prefix4 = *addr;
 518         p.prefixlen =
 519                 CHECK_FLAG(flags, ZEBRA_IFA_PEER) ? IPV4_MAX_BITLEN : prefixlen;
 520
 521         if (dest) {
 522                 memset(&d, 0, sizeof(d));
 523                 d.family = AF_INET;
 524                 d.u.prefix4 = *dest;
 525                 d.prefixlen = prefixlen;
 526                 ifc = connected_check_ptp(ifp, &p, &d);
 527         } else
 528                 ifc = connected_check_ptp(ifp, &p, NULL);
 529
 530         connected_delete_helper(ifc, &p);
 531 }
 532
 533 /* Add connected IPv6 route to the interface. */
 534 void connected_add_ipv6(struct interface *ifp, int flags,
 535                         const struct in6_addr *addr,
 536                         const struct in6_addr *dest, uint16_t prefixlen,
 537                         const char *label, uint32_t metric)
 538 {
 539         struct prefix_ipv6 *p;
 540         struct connected *ifc;
 541
 542         if (ipv6_martian(addr))
 543                 return;
 544
 545         /* Make connected structure. */
 546         ifc = connected_new();
 547         ifc->ifp = ifp;
 548         ifc->flags = flags;
 549         ifc->metric = metric;
 550         /* If we get a notification from the kernel,
 551          * we can safely assume the address is known to the kernel */
 552         SET_FLAG(ifc->conf, ZEBRA_IFC_QUEUED);
 553         if (!if_is_operative(ifp))
 554                 SET_FLAG(ifc->conf, ZEBRA_IFC_DOWN);
 555
 556         /* Allocate new connected address. */
 557         p = prefix_ipv6_new();
 558         p->family = AF_INET6;
 559         IPV6_ADDR_COPY(&p->prefix, addr);
 560         p->prefixlen = prefixlen;
 561         ifc->address = (struct prefix *)p;
 562
 563         /* Add global ipv6 address to the RA prefix list */
 564         if (!IN6_IS_ADDR_LINKLOCAL(&p->prefix))
 565                 rtadv_add_prefix(ifp->info, p);
 566
 567         if (dest) {
 568                 p = prefix_ipv6_new();
 569                 p->family = AF_INET6;
 570                 IPV6_ADDR_COPY(&p->prefix, dest);
 571                 p->prefixlen = prefixlen;
 572                 ifc->destination = (struct prefix *)p;
 573         } else {
 574                 if (CHECK_FLAG(ifc->flags, ZEBRA_IFA_PEER)) {
 575                         zlog_debug(
 576                                 "%s called for interface %s with peer flag set, but no peer address supplied",
 577                                 __func__, ifp->name);
 578                         UNSET_FLAG(ifc->flags, ZEBRA_IFA_PEER);
 579                 }
 580         }
 581
 582         /* Label of this address. */
 583         if (label)
 584                 ifc->label = XSTRDUP(MTYPE_CONNECTED_LABEL, label);
 585
 586         /* On Linux, we only get here when DAD is complete, therefore we can set
 587          * ZEBRA_IFC_REAL.
 588          *
 589          * On BSD, there currently doesn't seem to be a way to check for
 590          * completion of
 591          * DAD, so we replicate the old behaviour and set ZEBRA_IFC_REAL,
 592          * although DAD
 593          * might still be running.
 594          */
 595         SET_FLAG(ifc->conf, ZEBRA_IFC_REAL);
 596         connected_update(ifp, ifc);
 597 }
 598
 599 void connected_delete_ipv6(struct interface *ifp,
 600                            const struct in6_addr *address,
 601                            const struct in6_addr *dest, uint16_t prefixlen)
 602 {
 603         struct prefix p, d;
 604         struct connected *ifc;
 605
 606         memset(&p, 0, sizeof(p));
 607         p.family = AF_INET6;
 608         memcpy(&p.u.prefix6, address, sizeof(struct in6_addr));
 609         p.prefixlen = prefixlen;
 610
 611         /* Delete global ipv6 address from RA prefix list */
 612         if (!IN6_IS_ADDR_LINKLOCAL(&p.u.prefix6))
 613                 rtadv_delete_prefix(ifp->info, &p);
 614
 615         if (dest) {
 616                 memset(&d, 0, sizeof(d));
 617                 d.family = AF_INET6;
 618                 IPV6_ADDR_COPY(&d.u.prefix6, dest);
 619                 d.prefixlen = prefixlen;
 620                 ifc = connected_check_ptp(ifp, &p, &d);
 621         } else
 622                 ifc = connected_check_ptp(ifp, &p, NULL);
 623
 624         connected_delete_helper(ifc, &p);
 625 }
 626
 627 int connected_is_unnumbered(struct interface *ifp)
 628 {
 629         struct connected *connected;
 630         struct listnode *node;
 631
 632         for (ALL_LIST_ELEMENTS_RO(ifp->connected, node, connected)) {
 633                 if (CHECK_FLAG(connected->conf, ZEBRA_IFC_REAL)
 634                     && connected->address->family == AF_INET)
 635                         return CHECK_FLAG(connected->flags,
 636                                           ZEBRA_IFA_UNNUMBERED);
 637         }
 638         return 0;
 639 }