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 #include "lib_errors.h"
  33
  34 #include "ospfd/ospfd.h"
  35 #include "ospfd/ospf_network.h"
  36 #include "ospfd/ospf_interface.h"
  37 #include "ospfd/ospf_asbr.h"
  38 #include "ospfd/ospf_lsa.h"
  39 #include "ospfd/ospf_lsdb.h"
  40 #include "ospfd/ospf_neighbor.h"
  41 #include "ospfd/ospf_packet.h"
  42 #include "ospfd/ospf_dump.h"
  43
  44 /* Join to the OSPF ALL SPF ROUTERS multicast group. */
  45 int ospf_if_add_allspfrouters(struct ospf *top, struct prefix *p,
  46                               ifindex_t ifindex)
  47 {
  48         int ret;
  49
  50         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  51                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  52                                         ifindex);
  53         if (ret < 0)
  54                 flog_err(
  55                         EC_LIB_SOCKET,
  56                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllSPFRouters): %s; perhaps a kernel limit on # of multicast group memberships has been exceeded?",
  57                         top->fd, &p->u.prefix4, ifindex,
  58                         safe_strerror(errno));
  59         else {
  60                 if (IS_DEBUG_OSPF_EVENT)
  61                         zlog_debug(
  62                                 "interface %pI4 [%u] join AllSPFRouters Multicast group.",
  63                                 &p->u.prefix4, ifindex);
  64         }
  65
  66         return ret;
  67 }
  68
  69 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  70                                ifindex_t ifindex)
  71 {
  72         int ret;
  73
  74         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  75                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  76                                         ifindex);
  77         if (ret < 0)
  78                 flog_err(EC_LIB_SOCKET,
  79                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllSPFRouters): %s",
  80                          top->fd, &p->u.prefix4, ifindex,
  81                          safe_strerror(errno));
  82         else {
  83                 if (IS_DEBUG_OSPF_EVENT)
  84                         zlog_debug(
  85                                 "interface %pI4 [%u] leave AllSPFRouters Multicast group.",
  86                                 &p->u.prefix4, ifindex);
  87         }
  88
  89         return ret;
  90 }
  91
  92 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  93 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  94                             ifindex_t ifindex)
  95 {
  96         int ret;
  97
  98         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  99                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 100                                         ifindex);
 101         if (ret < 0)
 102                 flog_err(
 103                         EC_LIB_SOCKET,
 104                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllDRouters): %s; perhaps a kernel limit on # of multicast group memberships has been exceeded?",
 105                         top->fd, &p->u.prefix4, ifindex,
 106                         safe_strerror(errno));
 107         else
 108                 zlog_debug(
 109                         "interface %pI4 [%u] join AllDRouters Multicast group.",
 110                         &p->u.prefix4, ifindex);
 111
 112         return ret;
 113 }
 114
 115 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 116                              ifindex_t ifindex)
 117 {
 118         int ret;
 119
 120         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 121                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 122                                         ifindex);
 123         if (ret < 0)
 124                 flog_err(EC_LIB_SOCKET,
 125                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllDRouters): %s",
 126                          top->fd, &p->u.prefix4, ifindex,
 127                          safe_strerror(errno));
 128         else
 129                 zlog_debug(
 130                         "interface %pI4 [%u] leave AllDRouters Multicast group.",
 131                         &p->u.prefix4, ifindex);
 132
 133         return ret;
 134 }
 135
 136 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 137 {
 138         uint8_t val;
 139         int ret, len;
 140
 141         /* Prevent receiving self-origined multicast packets. */
 142         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 143         if (ret < 0)
 144                 flog_err(EC_LIB_SOCKET,
 145                          "can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 146                          top->fd, safe_strerror(errno));
 147
 148         /* Explicitly set multicast ttl to 1 -- endo. */
 149         val = 1;
 150         len = sizeof(val);
 151         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 152                          len);
 153         if (ret < 0)
 154                 flog_err(EC_LIB_SOCKET,
 155                          "can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 156                          top->fd, safe_strerror(errno));
 157 #ifndef GNU_LINUX
 158         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 159          * packet out of ifindex. Below would be used Non Linux system.
 160          */
 161         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 162         if (ret < 0)
 163                 flog_err(EC_LIB_SOCKET,
 164                          "can't setsockopt IP_MULTICAST_IF(fd %d, addr %pI4, ifindex %u): %s",
 165                          top->fd, &p->u.prefix4, ifindex,
 166                          safe_strerror(errno));
 167 #endif
 168
 169         return ret;
 170 }
 171
 172 int ospf_sock_init(struct ospf *ospf)
 173 {
 174         int ospf_sock;
 175         int ret, hincl = 1;
 176         int bufsize = (8 * 1024 * 1024);
 177
 178         /* silently ignore. already done */
 179         if (ospf->fd > 0)
 180                 return -1;
 181
 182         if (ospf->vrf_id == VRF_UNKNOWN) {
 183                 /* silently return since VRF is not ready */
 184                 return -1;
 185         }
 186         frr_with_privs(&ospfd_privs) {
 187                 ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
 188                                        ospf->vrf_id, ospf->name);
 189                 if (ospf_sock < 0) {
 190                         flog_err(EC_LIB_SOCKET,
 191                                  "ospf_read_sock_init: socket: %s",
 192                                  safe_strerror(errno));
 193                         return -1;
 194                 }
 195
 196 #ifdef IP_HDRINCL
 197                 /* we will include IP header with packet */
 198                 ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 199                                  sizeof(hincl));
 200                 if (ret < 0) {
 201                         flog_err(EC_LIB_SOCKET,
 202                                  "Can't set IP_HDRINCL option for fd %d: %s",
 203                                  ospf_sock, safe_strerror(errno));
 204                         break;
 205                 }
 206 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 207 #warning "IP_HDRINCL not available on this system"
 208 #warning "using IPTOS_PREC_INTERNETCONTROL"
 209                 ret = setsockopt_ipv4_tos(ospf_sock,
 210                                           IPTOS_PREC_INTERNETCONTROL);
 211                 if (ret < 0) {
 212                         flog_err(EC_LIB_SOCKET,
 213                                  "can't set sockopt IP_TOS %d to socket %d: %s",
 214                                  tos, ospf_sock, safe_strerror(errno));
 215                         break;
 216                 }
 217 #else /* !IPTOS_PREC_INTERNETCONTROL */
 218 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 219                 flog_err(EC_LIB_UNAVAILABLE, "IP_HDRINCL option not available");
 220 #endif /* IP_HDRINCL */
 221
 222                 ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 223
 224                 if (ret < 0)
 225                         flog_err(EC_LIB_SOCKET,
 226                                  "Can't set pktinfo option for fd %d",
 227                                  ospf_sock);
 228         }
 229
 230         setsockopt_so_sendbuf(ospf_sock, bufsize);
 231         setsockopt_so_recvbuf(ospf_sock, bufsize);
 232
 233         ospf->fd = ospf_sock;
 234         return ret;
 235 }