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
  37 #include "zebra/interface.h"
  38 #include "zebra/rib.h"
  39
  40 #include <ifaddrs.h>
  41
  42 /* Interface looking up using infamous SIOCGIFCONF. */
  43 static int interface_list_ioctl(void)
  44 {
  45         int ret;
  46         int sock;
  47 #define IFNUM_BASE 32
  48         int ifnum;
  49         struct ifreq *ifreq;
  50         struct ifconf ifconf;
  51         struct interface *ifp;
  52         int n;
  53         int lastlen;
  54
  55         /* Normally SIOCGIFCONF works with AF_INET socket. */
  56         sock = socket(AF_INET, SOCK_DGRAM, 0);
  57         if (sock < 0) {
  58                 zlog_warn("Can't make AF_INET socket stream: %s",
  59                           safe_strerror(errno));
  60                 return -1;
  61         }
  62
  63 /* Set initial ifreq count.  This will be double when SIOCGIFCONF
  64    fail.  Solaris has SIOCGIFNUM. */
  65 #ifdef SIOCGIFNUM
  66         ret = ioctl(sock, SIOCGIFNUM, &ifnum);
  67         if (ret < 0)
  68                 ifnum = IFNUM_BASE;
  69         else
  70                 ifnum++;
  71 #else
  72         ifnum = IFNUM_BASE;
  73 #endif /* SIOCGIFNUM */
  74
  75         ifconf.ifc_buf = NULL;
  76
  77         lastlen = 0;
  78         /* Loop until SIOCGIFCONF success. */
  79         for (;;) {
  80                 ifconf.ifc_len = sizeof(struct ifreq) * ifnum;
  81                 ifconf.ifc_buf =
  82                         XREALLOC(MTYPE_TMP, ifconf.ifc_buf, ifconf.ifc_len);
  83
  84                 ret = ioctl(sock, SIOCGIFCONF, &ifconf);
  85
  86                 if (ret < 0) {
  87                         zlog_warn("SIOCGIFCONF: %s", safe_strerror(errno));
  88                         goto end;
  89                 }
  90                 /* Repeatedly get info til buffer fails to grow. */
  91                 if (ifconf.ifc_len > lastlen) {
  92                         lastlen = ifconf.ifc_len;
  93                         ifnum += 10;
  94                         continue;
  95                 }
  96                 /* Success. */
  97                 break;
  98         }
  99
 100         /* Allocate interface. */
 101         ifreq = ifconf.ifc_req;
 102
 103 #ifdef OPEN_BSD
 104         for (n = 0; n < ifconf.ifc_len;) {
 105                 unsigned int size;
 106
 107                 ifreq = (struct ifreq *)((caddr_t)ifconf.ifc_req + n);
 108                 ifp = if_get_by_name_len(
 109                         ifreq->ifr_name,
 110                         strnlen(ifreq->ifr_name, sizeof(ifreq->ifr_name)),
 111                         VRF_DEFAULT, 0);
 112                 if_add_update(ifp);
 113                 size = ifreq->ifr_addr.sa_len;
 114                 if (size < sizeof(ifreq->ifr_addr))
 115                         size = sizeof(ifreq->ifr_addr);
 116                 size += sizeof(ifreq->ifr_name);
 117                 n += size;
 118         }
 119 #else
 120         for (n = 0; n < ifconf.ifc_len; n += sizeof(struct ifreq)) {
 121                 ifp = if_get_by_name_len(
 122                         ifreq->ifr_name,
 123                         strnlen(ifreq->ifr_name, sizeof(ifreq->ifr_name)),
 124                         VRF_DEFAULT, 0);
 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         ifp->ifindex = 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         strncpy(ifreq.ifr_name, ifp->name, IFNAMSIZ);
 152         ifreq.ifr_addr.sa_family = AF_INET;
 153
 154         /* Fetch Hardware address if available. */
 155         ret = if_ioctl(SIOCGIFHWADDR, (caddr_t)&ifreq);
 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                 zlog_err("getifaddrs(): %s", safe_strerror(errno));
 185                 return -1;
 186         }
 187
 188         for (ifapfree = ifap; ifap; ifap = ifap->ifa_next) {
 189                 if (ifap->ifa_addr == NULL) {
 190                         zlog_err(
 191                                 "%s: nonsensical ifaddr with NULL ifa_addr, ifname %s",
 192                                 __func__,
 193                                 (ifap->ifa_name ? ifap->ifa_name : "(null)"));
 194                         continue;
 195                 }
 196
 197                 ifp = if_lookup_by_name(ifap->ifa_name, VRF_DEFAULT);
 198                 if (ifp == NULL) {
 199                         zlog_err("if_getaddrs(): Can't lookup interface %s\n",
 200                                  ifap->ifa_name);
 201                         continue;
 202                 }
 203
 204                 if (ifap->ifa_addr->sa_family == AF_INET) {
 205                         struct sockaddr_in *addr;
 206                         struct sockaddr_in *mask;
 207                         struct sockaddr_in *dest;
 208                         struct in_addr *dest_pnt;
 209                         int flags = 0;
 210
 211                         addr = (struct sockaddr_in *)ifap->ifa_addr;
 212                         mask = (struct sockaddr_in *)ifap->ifa_netmask;
 213                         prefixlen = ip_masklen(mask->sin_addr);
 214
 215                         dest_pnt = NULL;
 216
 217                         if (if_is_pointopoint(ifp) && ifap->ifa_dstaddr
 218                             && !IPV4_ADDR_SAME(&addr->sin_addr,
 219                                                &((struct sockaddr_in *)
 220                                                          ifap->ifa_dstaddr)
 221                                                         ->sin_addr)) {
 222                                 dest = (struct sockaddr_in *)ifap->ifa_dstaddr;
 223                                 dest_pnt = &dest->sin_addr;
 224                                 flags = ZEBRA_IFA_PEER;
 225                         } else if (ifap->ifa_broadaddr
 226                                    && !IPV4_ADDR_SAME(
 227                                               &addr->sin_addr,
 228                                               &((struct sockaddr_in *)
 229                                                         ifap->ifa_broadaddr)
 230                                                        ->sin_addr)) {
 231                                 dest = (struct sockaddr_in *)
 232                                                ifap->ifa_broadaddr;
 233                                 dest_pnt = &dest->sin_addr;
 234                         }
 235
 236                         connected_add_ipv4(ifp, flags, &addr->sin_addr,
 237                                            prefixlen, dest_pnt, NULL);
 238                 }
 239                 if (ifap->ifa_addr->sa_family == AF_INET6) {
 240                         struct sockaddr_in6 *addr;
 241                         struct sockaddr_in6 *mask;
 242                         int flags = 0;
 243
 244                         addr = (struct sockaddr_in6 *)ifap->ifa_addr;
 245                         mask = (struct sockaddr_in6 *)ifap->ifa_netmask;
 246                         prefixlen = ip6_masklen(mask->sin6_addr);
 247
 248 #if defined(KAME)
 249                         if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr)) {
 250                                 addr->sin6_scope_id =
 251                                         ntohs(*(u_int16_t *)&addr->sin6_addr
 252                                                        .s6_addr[2]);
 253                                 addr->sin6_addr.s6_addr[2] =
 254                                         addr->sin6_addr.s6_addr[3] = 0;
 255                         }
 256 #endif
 257
 258                         connected_add_ipv6(ifp, flags, &addr->sin6_addr,
 259                                            prefixlen, NULL);
 260                 }
 261         }
 262
 263         freeifaddrs(ifapfree);
 264
 265         return 0;
 266 }
 267
 268 /* Fetch interface information via ioctl(). */
 269 static void interface_info_ioctl()
 270 {
 271         struct listnode *node, *nnode;
 272         struct interface *ifp;
 273
 274         for (ALL_LIST_ELEMENTS(vrf_iflist(VRF_DEFAULT), node, nnode, ifp)) {
 275                 if_get_index(ifp);
 276 #ifdef SIOCGIFHWADDR
 277                 if_get_hwaddr(ifp);
 278 #endif /* SIOCGIFHWADDR */
 279                 if_get_flags(ifp);
 280                 if_get_mtu(ifp);
 281                 if_get_metric(ifp);
 282         }
 283 }
 284
 285 /* Lookup all interface information. */
 286 void interface_list(struct zebra_ns *zns)
 287 {
 288
 289         zlog_info("interface_list: NS %u", zns->ns_id);
 290
 291 /* Linux can do both proc & ioctl, ioctl is the only way to get
 292    interface aliases in 2.2 series kernels. */
 293 #ifdef HAVE_PROC_NET_DEV
 294         interface_list_proc();
 295 #endif /* HAVE_PROC_NET_DEV */
 296         interface_list_ioctl();
 297
 298         /* After listing is done, get index, address, flags and other
 299            interface's information. */
 300         interface_info_ioctl();
 301
 302         if_getaddrs();
 303
 304 #if defined(HAVE_PROC_NET_IF_INET6)
 305         /* Linux provides interface's IPv6 address via
 306            /proc/net/if_inet6. */
 307         ifaddr_proc_ipv6();
 308 #endif /* HAVE_PROC_NET_IF_INET6 */
 309 }
 310
 311 #endif /* OPEN_BSD */