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 "log.h"
  33 #include "vrf.h"
  34 #include "vty.h"
  35 #include "lib_errors.h"
  36
  37 #include "zebra/interface.h"
  38 #include "zebra/rib.h"
  39 #include "zebra/rt.h"
  40 #include "zebra/zebra_errors.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                 flog_err_sys(EC_LIB_SOCKET,
  61                              "Can't make AF_INET socket stream: %s",
  62                              safe_strerror(errno));
  63                 return -1;
  64         }
  65
  66 /* Set initial ifreq count.  This will be double when SIOCGIFCONF
  67    fail.  Solaris has SIOCGIFNUM. */
  68 #ifdef SIOCGIFNUM
  69         ret = ioctl(sock, SIOCGIFNUM, &ifnum);
  70         if (ret < 0)
  71                 ifnum = IFNUM_BASE;
  72         else
  73                 ifnum++;
  74 #else
  75         ifnum = IFNUM_BASE;
  76 #endif /* SIOCGIFNUM */
  77
  78         ifconf.ifc_buf = NULL;
  79
  80         lastlen = 0;
  81         /* Loop until SIOCGIFCONF success. */
  82         for (;;) {
  83                 ifconf.ifc_len = sizeof(struct ifreq) * ifnum;
  84                 ifconf.ifc_buf =
  85                         XREALLOC(MTYPE_TMP, ifconf.ifc_buf, ifconf.ifc_len);
  86
  87                 ret = ioctl(sock, SIOCGIFCONF, &ifconf);
  88
  89                 if (ret < 0) {
  90                         flog_err_sys(EC_LIB_SYSTEM_CALL, "SIOCGIFCONF: %s",
  91                                      safe_strerror(errno));
  92                         goto end;
  93                 }
  94                 /* Repeatedly get info til buffer fails to grow. */
  95                 if (ifconf.ifc_len > lastlen) {
  96                         lastlen = ifconf.ifc_len;
  97                         ifnum += 10;
  98                         continue;
  99                 }
 100                 /* Success. */
 101                 break;
 102         }
 103
 104         /* Allocate interface. */
 105         ifreq = ifconf.ifc_req;
 106
 107 #ifdef OPEN_BSD
 108         for (n = 0; n < ifconf.ifc_len;) {
 109                 unsigned int size;
 110
 111                 ifreq = (struct ifreq *)((caddr_t)ifconf.ifc_req + n);
 112                 ifp = if_get_by_name(ifreq->ifr_name, VRF_DEFAULT);
 113                 if_add_update(ifp);
 114                 size = ifreq->ifr_addr.sa_len;
 115                 if (size < sizeof(ifreq->ifr_addr))
 116                         size = sizeof(ifreq->ifr_addr);
 117                 size += sizeof(ifreq->ifr_name);
 118                 n += size;
 119         }
 120 #else
 121         for (n = 0; n < ifconf.ifc_len; n += sizeof(struct ifreq)) {
 122                 ifp = if_get_by_name(ifreq->ifr_name, VRF_DEFAULT);
 123                 if_add_update(ifp);
 124                 ifreq++;
 125         }
 126 #endif /* OPEN_BSD */
 127
 128 end:
 129         close(sock);
 130         XFREE(MTYPE_TMP, ifconf.ifc_buf);
 131
 132         return ret;
 133 }
 134
 135 /* Get interface's index by ioctl. */
 136 static int if_get_index(struct interface *ifp)
 137 {
 138         if_set_index(ifp, if_nametoindex(ifp->name));
 139         return ifp->ifindex;
 140 }
 141
 142 #ifdef SIOCGIFHWADDR
 143 static int if_get_hwaddr(struct interface *ifp)
 144 {
 145         int ret;
 146         struct ifreq ifreq;
 147         int i;
 148
 149         strlcpy(ifreq.ifr_name, ifp->name, sizeof(ifreq.ifr_name));
 150         ifreq.ifr_addr.sa_family = AF_INET;
 151
 152         /* Fetch Hardware address if available. */
 153         ret = vrf_if_ioctl(SIOCGIFHWADDR, (caddr_t)&ifreq, ifp->vrf_id);
 154         if (ret < 0)
 155                 ifp->hw_addr_len = 0;
 156         else {
 157                 memcpy(ifp->hw_addr, ifreq.ifr_hwaddr.sa_data, 6);
 158
 159                 for (i = 0; i < 6; i++)
 160                         if (ifp->hw_addr[i] != 0)
 161                                 break;
 162
 163                 if (i == 6)
 164                         ifp->hw_addr_len = 0;
 165                 else
 166                         ifp->hw_addr_len = 6;
 167         }
 168         return 0;
 169 }
 170 #endif /* SIOCGIFHWADDR */
 171
 172 static int if_getaddrs(void)
 173 {
 174         int ret;
 175         struct ifaddrs *ifap;
 176         struct ifaddrs *ifapfree;
 177         struct interface *ifp;
 178         int prefixlen;
 179
 180         ret = getifaddrs(&ifap);
 181         if (ret != 0) {
 182                 flog_err_sys(EC_LIB_SYSTEM_CALL, "getifaddrs(): %s",
 183                              safe_strerror(errno));
 184                 return -1;
 185         }
 186
 187         for (ifapfree = ifap; ifap; ifap = ifap->ifa_next) {
 188                 if (ifap->ifa_addr == NULL) {
 189                         flog_err(
 190                                 EC_LIB_INTERFACE,
 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                         flog_err(EC_LIB_INTERFACE,
 200                                  "if_getaddrs(): Can't lookup interface %s\n",
 201                                  ifap->ifa_name);
 202                         continue;
 203                 }
 204
 205                 if (ifap->ifa_addr->sa_family == AF_INET) {
 206                         struct sockaddr_in *addr;
 207                         struct sockaddr_in *mask;
 208                         struct sockaddr_in *dest;
 209                         struct in_addr *dest_pnt;
 210                         int flags = 0;
 211
 212                         addr = (struct sockaddr_in *)ifap->ifa_addr;
 213                         mask = (struct sockaddr_in *)ifap->ifa_netmask;
 214                         prefixlen = ip_masklen(mask->sin_addr);
 215
 216                         dest_pnt = NULL;
 217
 218                         if (if_is_pointopoint(ifp) && ifap->ifa_dstaddr
 219                             && !IPV4_ADDR_SAME(&addr->sin_addr,
 220                                                &((struct sockaddr_in *)
 221                                                          ifap->ifa_dstaddr)
 222                                                         ->sin_addr)) {
 223                                 dest = (struct sockaddr_in *)ifap->ifa_dstaddr;
 224                                 dest_pnt = &dest->sin_addr;
 225                                 flags = ZEBRA_IFA_PEER;
 226                         } else if (ifap->ifa_broadaddr
 227                                    && !IPV4_ADDR_SAME(
 228                                               &addr->sin_addr,
 229                                               &((struct sockaddr_in *)
 230                                                         ifap->ifa_broadaddr)
 231                                                        ->sin_addr)) {
 232                                 dest = (struct sockaddr_in *)
 233                                                ifap->ifa_broadaddr;
 234                                 dest_pnt = &dest->sin_addr;
 235                         }
 236
 237                         connected_add_ipv4(ifp, flags, &addr->sin_addr,
 238                                            prefixlen, dest_pnt, NULL,
 239                                            METRIC_MAX);
 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, METRIC_MAX);
 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 */