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                 zlog_warn(
  55                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
  56                         "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
  57                         "on # of multicast group memberships has been exceeded?",
  58                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  59                         safe_strerror(errno));
  60         else {
  61                 if (IS_DEBUG_OSPF_EVENT)
  62                         zlog_debug(
  63                                 "interface %s [%u] join AllSPFRouters Multicast group.",
  64                                 inet_ntoa(p->u.prefix4), ifindex);
  65         }
  66
  67         return ret;
  68 }
  69
  70 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  71                                ifindex_t ifindex)
  72 {
  73         int ret;
  74
  75         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  76                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  77                                         ifindex);
  78         if (ret < 0)
  79                 zlog_warn(
  80                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  81                         "ifindex %u, AllSPFRouters): %s",
  82                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  83                         safe_strerror(errno));
  84         else {
  85                 if (IS_DEBUG_OSPF_EVENT)
  86                         zlog_debug(
  87                                 "interface %s [%u] leave AllSPFRouters Multicast group.",
  88                                 inet_ntoa(p->u.prefix4), ifindex);
  89         }
  90
  91         return ret;
  92 }
  93
  94 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  95 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  96                             ifindex_t ifindex)
  97 {
  98         int ret;
  99
 100         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
 101                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 102                                         ifindex);
 103         if (ret < 0)
 104                 zlog_warn(
 105                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 106                         "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 107                         "on # of multicast group memberships has been exceeded?",
 108                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 109                         safe_strerror(errno));
 110         else
 111                 zlog_debug(
 112                         "interface %s [%u] join AllDRouters Multicast group.",
 113                         inet_ntoa(p->u.prefix4), ifindex);
 114
 115         return ret;
 116 }
 117
 118 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 119                              ifindex_t ifindex)
 120 {
 121         int ret;
 122
 123         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 124                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 125                                         ifindex);
 126         if (ret < 0)
 127                 zlog_warn(
 128                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 129                         "ifindex %u, AllDRouters): %s",
 130                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 131                         safe_strerror(errno));
 132         else
 133                 zlog_debug(
 134                         "interface %s [%u] leave AllDRouters Multicast group.",
 135                         inet_ntoa(p->u.prefix4), ifindex);
 136
 137         return ret;
 138 }
 139
 140 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 141 {
 142         uint8_t val;
 143         int ret, len;
 144
 145         /* Prevent receiving self-origined multicast packets. */
 146         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 147         if (ret < 0)
 148                 zlog_warn("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 149                           top->fd, safe_strerror(errno));
 150
 151         /* Explicitly set multicast ttl to 1 -- endo. */
 152         val = 1;
 153         len = sizeof(val);
 154         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 155                          len);
 156         if (ret < 0)
 157                 zlog_warn("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 158                           top->fd, safe_strerror(errno));
 159 #ifndef GNU_LINUX
 160         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 161          * packet out of ifindex. Below would be used Non Linux system.
 162          */
 163         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 164         if (ret < 0)
 165                 zlog_warn(
 166                         "can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 167                         "ifindex %u): %s",
 168                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 169                         safe_strerror(errno));
 170 #endif
 171
 172         return ret;
 173 }
 174
 175 int ospf_sock_init(struct ospf *ospf)
 176 {
 177         int ospf_sock;
 178         int ret, hincl = 1;
 179         int bufsize = (8 * 1024 * 1024);
 180
 181         /* silently ignore. already done */
 182         if (ospf->fd > 0)
 183                 return -1;
 184
 185         if (ospf->vrf_id == VRF_UNKNOWN) {
 186                 /* silently return since VRF is not ready */
 187                 return -1;
 188         }
 189         frr_elevate_privs(&ospfd_privs) {
 190                 ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
 191                                        ospf->vrf_id, ospf->name);
 192                 if (ospf_sock < 0) {
 193                         zlog_err("ospf_read_sock_init: socket: %s",
 194                                  safe_strerror(errno));
 195                         exit(1);
 196                 }
 197
 198 #ifdef IP_HDRINCL
 199                 /* we will include IP header with packet */
 200                 ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 201                                  sizeof(hincl));
 202                 if (ret < 0) {
 203                         zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
 204                                   ospf_sock, safe_strerror(errno));
 205                         close(ospf_sock);
 206                         break;
 207                 }
 208 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 209 #warning "IP_HDRINCL not available on this system"
 210 #warning "using IPTOS_PREC_INTERNETCONTROL"
 211                 ret = setsockopt_ipv4_tos(ospf_sock,
 212                                           IPTOS_PREC_INTERNETCONTROL);
 213                 if (ret < 0) {
 214                         zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s",
 215                                   tos, ospf_sock, safe_strerror(errno));
 216                         close(ospf_sock); /* Prevent sd leak. */
 217                         break;
 218                 }
 219 #else /* !IPTOS_PREC_INTERNETCONTROL */
 220 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 221                 zlog_warn("IP_HDRINCL option not available");
 222 #endif /* IP_HDRINCL */
 223
 224                 ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 225
 226                 if (ret < 0)
 227                         zlog_warn("Can't set pktinfo option for fd %d",
 228                                   ospf_sock);
 229
 230                 setsockopt_so_sendbuf(ospf_sock, bufsize);
 231                 setsockopt_so_recvbuf(ospf_sock, bufsize);
 232         }
 233
 234         ospf->fd = ospf_sock;
 235         return ret;
 236 }