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