zebra/if_ioctl.c

   1 /*
   2  * Interface looking up by ioctl ().
   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 #ifdef OPEN_BSD
  25
  26 #include "if.h"
  27 #include "sockunion.h"
  28 #include "prefix.h"
  29 #include "ioctl.h"
  30 #include "connected.h"
  31 #include "memory.h"
  32 #include "zebra_memory.h"
  33 #include "log.h"
  34 #include "vrf.h"
  35 #include "vty.h"
  36 #include "lib_errors.h"
  37
  38 #include "zebra/interface.h"
  39 #include "zebra/rib.h"
  40 #include "zebra/rt.h"
  41 #include "zebra/zebra_errors.h"
  42
  43 #include <ifaddrs.h>
  44
  45 /* Interface looking up using infamous SIOCGIFCONF. */
  46 static int interface_list_ioctl(void)
  47 {
  48         int ret;
  49         int sock;
  50 #define IFNUM_BASE 32
  51         int ifnum;
  52         struct ifreq *ifreq;
  53         struct ifconf ifconf;
  54         struct interface *ifp;
  55         int n;
  56         int lastlen;
  57         struct vrf *vrf = vrf_lookup_by_id(VRF_DEFAULT);
  58
  59         /* Normally SIOCGIFCONF works with AF_INET socket. */
  60         sock = socket(AF_INET, SOCK_DGRAM, 0);
  61         if (sock < 0) {
  62                 flog_err_sys(EC_LIB_SOCKET,
  63                              "Can't make AF_INET socket stream: %s",
  64                              safe_strerror(errno));
  65                 return -1;
  66         }
  67
  68 /* Set initial ifreq count.  This will be double when SIOCGIFCONF
  69    fail.  Solaris has SIOCGIFNUM. */
  70 #ifdef SIOCGIFNUM
  71         ret = ioctl(sock, SIOCGIFNUM, &ifnum);
  72         if (ret < 0)
  73                 ifnum = IFNUM_BASE;
  74         else
  75                 ifnum++;
  76 #else
  77         ifnum = IFNUM_BASE;
  78 #endif /* SIOCGIFNUM */
  79
  80         ifconf.ifc_buf = NULL;
  81
  82         lastlen = 0;
  83         /* Loop until SIOCGIFCONF success. */
  84         for (;;) {
  85                 ifconf.ifc_len = sizeof(struct ifreq) * ifnum;
  86                 ifconf.ifc_buf =
  87                         XREALLOC(MTYPE_TMP, ifconf.ifc_buf, ifconf.ifc_len);
  88
  89                 ret = ioctl(sock, SIOCGIFCONF, &ifconf);
  90
  91                 if (ret < 0) {
  92                         flog_err_sys(EC_LIB_SYSTEM_CALL, "SIOCGIFCONF: %s",
  93                                      safe_strerror(errno));
  94                         goto end;
  95                 }
  96                 /* Repeatedly get info til buffer fails to grow. */
  97                 if (ifconf.ifc_len > lastlen) {
  98                         lastlen = ifconf.ifc_len;
  99                         ifnum += 10;
 100                         continue;
 101                 }
 102                 /* Success. */
 103                 break;
 104         }
 105
 106         /* Allocate interface. */
 107         ifreq = ifconf.ifc_req;
 108
 109 #ifdef OPEN_BSD
 110         for (n = 0; n < ifconf.ifc_len;) {
 111                 unsigned int size;
 112
 113                 ifreq = (struct ifreq *)((caddr_t)ifconf.ifc_req + n);
 114                 ifp = if_get_by_name(ifreq->ifr_name, vrf);
 115                 if_add_update(ifp);
 116                 size = ifreq->ifr_addr.sa_len;
 117                 if (size < sizeof(ifreq->ifr_addr))
 118                         size = sizeof(ifreq->ifr_addr);
 119                 size += sizeof(ifreq->ifr_name);
 120                 n += size;
 121         }
 122 #else
 123         for (n = 0; n < ifconf.ifc_len; n += sizeof(struct ifreq)) {
 124                 ifp = if_get_by_name(ifreq->ifr_name, vrf);
 125                 if_add_update(ifp);
 126                 ifreq++;
 127         }
 128 #endif /* OPEN_BSD */
 129
 130 end:
 131         close(sock);
 132         XFREE(MTYPE_TMP, ifconf.ifc_buf);
 133
 134         return ret;
 135 }
 136
 137 /* Get interface's index by ioctl. */
 138 static int if_get_index(struct interface *ifp)
 139 {
 140         if_set_index(ifp, if_nametoindex(ifp->name));
 141         return ifp->ifindex;
 142 }
 143
 144 #ifdef SIOCGIFHWADDR
 145 static int if_get_hwaddr(struct interface *ifp)
 146 {
 147         int ret;
 148         struct ifreq ifreq;
 149         int i;
 150
 151         strlcpy(ifreq.ifr_name, ifp->name, sizeof(ifreq.ifr_name));
 152         ifreq.ifr_addr.sa_family = AF_INET;
 153
 154         /* Fetch Hardware address if available. */
 155         ret = vrf_if_ioctl(SIOCGIFHWADDR, (caddr_t)&ifreq, ifp->vrf_id);
 156         if (ret < 0)
 157                 ifp->hw_addr_len = 0;
 158         else {
 159                 memcpy(ifp->hw_addr, ifreq.ifr_hwaddr.sa_data, 6);
 160
 161                 for (i = 0; i < 6; i++)
 162                         if (ifp->hw_addr[i] != 0)
 163                                 break;
 164
 165                 if (i == 6)
 166                         ifp->hw_addr_len = 0;
 167                 else
 168                         ifp->hw_addr_len = 6;
 169         }
 170         return 0;
 171 }
 172 #endif /* SIOCGIFHWADDR */
 173
 174 static int if_getaddrs(void)
 175 {
 176         int ret;
 177         struct ifaddrs *ifap;
 178         struct ifaddrs *ifapfree;
 179         struct interface *ifp;
 180         int prefixlen;
 181
 182         ret = getifaddrs(&ifap);
 183         if (ret != 0) {
 184                 flog_err_sys(EC_LIB_SYSTEM_CALL, "getifaddrs(): %s",
 185                              safe_strerror(errno));
 186                 return -1;
 187         }
 188
 189         for (ifapfree = ifap; ifap; ifap = ifap->ifa_next) {
 190                 if (ifap->ifa_addr == NULL) {
 191                         flog_err(
 192                                 EC_LIB_INTERFACE,
 193                                 "%s: nonsensical ifaddr with NULL ifa_addr, ifname %s",
 194                                 __func__,
 195                                 (ifap->ifa_name ? ifap->ifa_name : "(null)"));
 196                         continue;
 197                 }
 198
 199                 ifp = if_lookup_by_name(ifap->ifa_name,
 200                                         vrf_lookup_by_id(VRF_DEFAULT));
 201                 if (ifp == NULL) {
 202                         flog_err(EC_LIB_INTERFACE,
 203                                  "if_getaddrs(): Can't lookup interface %s\n",
 204                                  ifap->ifa_name);
 205                         continue;
 206                 }
 207
 208                 if (ifap->ifa_addr->sa_family == AF_INET) {
 209                         struct sockaddr_in *addr;
 210                         struct sockaddr_in *mask;
 211                         struct sockaddr_in *dest;
 212                         struct in_addr *dest_pnt;
 213                         int flags = 0;
 214
 215                         addr = (struct sockaddr_in *)ifap->ifa_addr;
 216                         mask = (struct sockaddr_in *)ifap->ifa_netmask;
 217                         prefixlen = ip_masklen(mask->sin_addr);
 218
 219                         dest_pnt = NULL;
 220
 221                         if (if_is_pointopoint(ifp) && ifap->ifa_dstaddr
 222                             && !IPV4_ADDR_SAME(&addr->sin_addr,
 223                                                &((struct sockaddr_in *)
 224                                                          ifap->ifa_dstaddr)
 225                                                         ->sin_addr)) {
 226                                 dest = (struct sockaddr_in *)ifap->ifa_dstaddr;
 227                                 dest_pnt = &dest->sin_addr;
 228                                 flags = ZEBRA_IFA_PEER;
 229                         } else if (ifap->ifa_broadaddr
 230                                    && !IPV4_ADDR_SAME(
 231                                               &addr->sin_addr,
 232                                               &((struct sockaddr_in *)
 233                                                         ifap->ifa_broadaddr)
 234                                                        ->sin_addr)) {
 235                                 dest = (struct sockaddr_in *)
 236                                                ifap->ifa_broadaddr;
 237                                 dest_pnt = &dest->sin_addr;
 238                         }
 239
 240                         connected_add_ipv4(ifp, flags, &addr->sin_addr,
 241                                            prefixlen, dest_pnt, NULL,
 242                                            METRIC_MAX);
 243                 }
 244                 if (ifap->ifa_addr->sa_family == AF_INET6) {
 245                         struct sockaddr_in6 *addr;
 246                         struct sockaddr_in6 *mask;
 247                         int flags = 0;
 248
 249                         addr = (struct sockaddr_in6 *)ifap->ifa_addr;
 250                         mask = (struct sockaddr_in6 *)ifap->ifa_netmask;
 251                         prefixlen = ip6_masklen(mask->sin6_addr);
 252
 253 #if defined(KAME)
 254                         if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
 255                                 addr->sin6_scope_id =
 256                                         ntohs(*(uint16_t *)&addr->sin6_addr
 257                                                        .s6_addr[2]);
 258                                 addr->sin6_addr.s6_addr[2] =
 259                                         addr->sin6_addr.s6_addr[3] = 0;
 260                         }
 261 #endif
 262
 263                         connected_add_ipv6(ifp, flags, &addr->sin6_addr, NULL,
 264                                            prefixlen, NULL, METRIC_MAX);
 265                 }
 266         }
 267
 268         freeifaddrs(ifapfree);
 269
 270         return 0;
 271 }
 272
 273 /* Fetch interface information via ioctl(). */
 274 static void interface_info_ioctl()
 275 {
 276         struct vrf *vrf = vrf_lookup_by_id(VRF_DEFAULT);
 277         struct interface *ifp;
 278
 279         FOR_ALL_INTERFACES (vrf, ifp) {
 280                 if_get_index(ifp);
 281 #ifdef SIOCGIFHWADDR
 282                 if_get_hwaddr(ifp);
 283 #endif /* SIOCGIFHWADDR */
 284                 if_get_flags(ifp);
 285                 if_get_mtu(ifp);
 286                 if_get_metric(ifp);
 287         }
 288 }
 289
 290 /* Lookup all interface information. */
 291 void interface_list(struct zebra_ns *zns)
 292 {
 293
 294         zlog_info("interface_list: NS %u", zns->ns_id);
 295
 296 /* Linux can do both proc & ioctl, ioctl is the only way to get
 297    interface aliases in 2.2 series kernels. */
 298 #ifdef HAVE_PROC_NET_DEV
 299         interface_list_proc();
 300 #endif /* HAVE_PROC_NET_DEV */
 301         interface_list_ioctl();
 302
 303         /* After listing is done, get index, address, flags and other
 304            interface's information. */
 305         interface_info_ioctl();
 306
 307         if_getaddrs();
 308
 309 #if defined(HAVE_PROC_NET_IF_INET6)
 310         /* Linux provides interface's IPv6 address via
 311            /proc/net/if_inet6. */
 312         ifaddr_proc_ipv6();
 313 #endif /* HAVE_PROC_NET_IF_INET6 */
 314 }
 315
 316 #endif /* OPEN_BSD */