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