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