ospfd/ospf_network.c

   1 /*
   2  * OSPF network related functions
   3  *   Copyright (C) 1999 Toshiaki Takada
   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 #include "thread.h"
  25 #include "linklist.h"
  26 #include "prefix.h"
  27 #include "if.h"
  28 #include "sockunion.h"
  29 #include "log.h"
  30 #include "sockopt.h"
  31 #include "privs.h"
  32
  33 #include "ospfd/ospfd.h"
  34 #include "ospfd/ospf_network.h"
  35 #include "ospfd/ospf_interface.h"
  36 #include "ospfd/ospf_asbr.h"
  37 #include "ospfd/ospf_lsa.h"
  38 #include "ospfd/ospf_lsdb.h"
  39 #include "ospfd/ospf_neighbor.h"
  40 #include "ospfd/ospf_packet.h"
  41
  42
  43 /* Join to the OSPF ALL SPF ROUTERS multicast group. */
  44 int ospf_if_add_allspfrouters(struct ospf *top, struct prefix *p,
  45                               ifindex_t ifindex)
  46 {
  47         int ret;
  48
  49         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  50                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  51                                         ifindex);
  52         if (ret < 0)
  53                 zlog_warn(
  54                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
  55                         "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
  56                         "on # of multicast group memberships has been exceeded?",
  57                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  58                         safe_strerror(errno));
  59         else
  60                 zlog_debug(
  61                         "interface %s [%u] join AllSPFRouters Multicast group.",
  62                         inet_ntoa(p->u.prefix4), ifindex);
  63
  64         return ret;
  65 }
  66
  67 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  68                                ifindex_t ifindex)
  69 {
  70         int ret;
  71
  72         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  73                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  74                                         ifindex);
  75         if (ret < 0)
  76                 zlog_warn(
  77                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  78                         "ifindex %u, AllSPFRouters): %s",
  79                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  80                         safe_strerror(errno));
  81         else
  82                 zlog_debug(
  83                         "interface %s [%u] leave AllSPFRouters Multicast group.",
  84                         inet_ntoa(p->u.prefix4), ifindex);
  85
  86         return ret;
  87 }
  88
  89 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  90 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  91                             ifindex_t ifindex)
  92 {
  93         int ret;
  94
  95         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  96                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
  97                                         ifindex);
  98         if (ret < 0)
  99                 zlog_warn(
 100                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 101                         "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 102                         "on # of multicast group memberships has been exceeded?",
 103                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 104                         safe_strerror(errno));
 105         else
 106                 zlog_debug(
 107                         "interface %s [%u] join AllDRouters Multicast group.",
 108                         inet_ntoa(p->u.prefix4), ifindex);
 109
 110         return ret;
 111 }
 112
 113 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 114                              ifindex_t ifindex)
 115 {
 116         int ret;
 117
 118         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 119                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 120                                         ifindex);
 121         if (ret < 0)
 122                 zlog_warn(
 123                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 124                         "ifindex %u, AllDRouters): %s",
 125                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 126                         safe_strerror(errno));
 127         else
 128                 zlog_debug(
 129                         "interface %s [%u] leave AllDRouters Multicast group.",
 130                         inet_ntoa(p->u.prefix4), ifindex);
 131
 132         return ret;
 133 }
 134
 135 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 136 {
 137         u_char val;
 138         int ret, len;
 139
 140         /* Prevent receiving self-origined multicast packets. */
 141         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 142         if (ret < 0)
 143                 zlog_warn("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 144                           top->fd, safe_strerror(errno));
 145
 146         /* Explicitly set multicast ttl to 1 -- endo. */
 147         val = 1;
 148         len = sizeof(val);
 149         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 150                          len);
 151         if (ret < 0)
 152                 zlog_warn("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 153                           top->fd, safe_strerror(errno));
 154 #ifndef GNU_LINUX
 155         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 156          * packet out of ifindex. Below would be used Non Linux system.
 157          */
 158         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 159         if (ret < 0)
 160                 zlog_warn(
 161                         "can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 162                         "ifindex %u): %s",
 163                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 164                         safe_strerror(errno));
 165 #endif
 166
 167         return ret;
 168 }
 169
 170 int ospf_bind_vrfdevice(struct ospf *ospf, int ospf_sock)
 171 {
 172         int ret = 0;
 173
 174 #ifdef SO_BINDTODEVICE
 175
 176         if (ospf && ospf->vrf_id != VRF_DEFAULT &&
 177             ospf->vrf_id != VRF_UNKNOWN) {
 178                 ret = setsockopt(ospf_sock, SOL_SOCKET, SO_BINDTODEVICE,
 179                                  ospf->name,
 180                                  strlen(ospf->name));
 181                 if (ret < 0) {
 182                         int save_errno = errno;
 183
 184                         zlog_warn("%s: Could not setsockopt SO_BINDTODEVICE %s",
 185                                         __PRETTY_FUNCTION__,
 186                                         safe_strerror(save_errno));
 187                 } else {
 188                         zlog_debug("%s: Bind socket %d to vrf %s id %u device",
 189                                    __PRETTY_FUNCTION__, ospf_sock,
 190                                    ospf->name, ospf->vrf_id);
 191                 }
 192         }
 193 #endif
 194         return ret;
 195 }
 196
 197 int ospf_sock_init(struct ospf *ospf)
 198 {
 199         int ospf_sock;
 200         int ret, hincl = 1;
 201         int bufsize = (8 * 1024 * 1024);
 202
 203         if (ospfd_privs.change(ZPRIVS_RAISE)) {
 204                 zlog_err("ospf_sock_init: could not raise privs, %s",
 205                          safe_strerror(errno));
 206         }
 207
 208         ospf_sock = socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP);
 209         if (ospf_sock < 0) {
 210                 int save_errno = errno;
 211
 212                 if (ospfd_privs.change(ZPRIVS_LOWER))
 213                         zlog_err("ospf_sock_init: could not lower privs, %s",
 214                                  safe_strerror(errno));
 215                 zlog_err("ospf_read_sock_init: socket: %s",
 216                          safe_strerror(save_errno));
 217                 exit(1);
 218         }
 219
 220         ret = ospf_bind_vrfdevice(ospf, ospf_sock);
 221         if (ret < 0) {
 222                 close(ospf_sock);
 223                 goto out;
 224         }
 225
 226 #ifdef IP_HDRINCL
 227         /* we will include IP header with packet */
 228         ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 229                          sizeof(hincl));
 230         if (ret < 0) {
 231                 int save_errno = errno;
 232
 233                 zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
 234                           ospf_sock, safe_strerror(save_errno));
 235                 close(ospf_sock);
 236                 goto out;
 237         }
 238 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 239 #warning "IP_HDRINCL not available on this system"
 240 #warning "using IPTOS_PREC_INTERNETCONTROL"
 241         ret = setsockopt_ipv4_tos(ospf_sock, IPTOS_PREC_INTERNETCONTROL);
 242         if (ret < 0) {
 243                 int save_errno = errno;
 244
 245                 zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s", tos,
 246                           ospf_sock, safe_strerror(save_errno));
 247                 close(ospf_sock); /* Prevent sd leak. */
 248                 goto out;
 249         }
 250 #else /* !IPTOS_PREC_INTERNETCONTROL */
 251 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 252         zlog_warn("IP_HDRINCL option not available");
 253 #endif /* IP_HDRINCL */
 254
 255         ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 256
 257         if (ret < 0)
 258                 zlog_warn("Can't set pktinfo option for fd %d", ospf_sock);
 259
 260         setsockopt_so_sendbuf(ospf_sock, bufsize);
 261         setsockopt_so_recvbuf(ospf_sock, bufsize);
 262
 263         ospf->fd = ospf_sock;
 264 out:
 265         if (ospfd_privs.change(ZPRIVS_LOWER)) {
 266                 zlog_err("ospf_sock_init: could not lower privs, %s",
 267                          safe_strerror(errno));
 268         }
 269         return ret;
 270 }