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 %s, "
  57                         "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
  58                         "on # of multicast group memberships has been exceeded?",
  59                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  60                         safe_strerror(errno));
  61         else {
  62                 if (IS_DEBUG_OSPF_EVENT)
  63                         zlog_debug(
  64                                 "interface %s [%u] join AllSPFRouters Multicast group.",
  65                                 inet_ntoa(p->u.prefix4), ifindex);
  66         }
  67
  68         return ret;
  69 }
  70
  71 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  72                                ifindex_t ifindex)
  73 {
  74         int ret;
  75
  76         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  77                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  78                                         ifindex);
  79         if (ret < 0)
  80                 flog_err(EC_LIB_SOCKET,
  81                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  82                          "ifindex %u, AllSPFRouters): %s",
  83                          top->fd, inet_ntoa(p->u.prefix4), ifindex,
  84                          safe_strerror(errno));
  85         else {
  86                 if (IS_DEBUG_OSPF_EVENT)
  87                         zlog_debug(
  88                                 "interface %s [%u] leave AllSPFRouters Multicast group.",
  89                                 inet_ntoa(p->u.prefix4), ifindex);
  90         }
  91
  92         return ret;
  93 }
  94
  95 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  96 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  97                             ifindex_t ifindex)
  98 {
  99         int ret;
 100
 101         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
 102                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 103                                         ifindex);
 104         if (ret < 0)
 105                 flog_err(
 106                         EC_LIB_SOCKET,
 107                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 108                         "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 109                         "on # of multicast group memberships has been exceeded?",
 110                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 111                         safe_strerror(errno));
 112         else
 113                 zlog_debug(
 114                         "interface %s [%u] join AllDRouters Multicast group.",
 115                         inet_ntoa(p->u.prefix4), ifindex);
 116
 117         return ret;
 118 }
 119
 120 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 121                              ifindex_t ifindex)
 122 {
 123         int ret;
 124
 125         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 126                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 127                                         ifindex);
 128         if (ret < 0)
 129                 flog_err(EC_LIB_SOCKET,
 130                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 131                          "ifindex %u, AllDRouters): %s",
 132                          top->fd, inet_ntoa(p->u.prefix4), ifindex,
 133                          safe_strerror(errno));
 134         else
 135                 zlog_debug(
 136                         "interface %s [%u] leave AllDRouters Multicast group.",
 137                         inet_ntoa(p->u.prefix4), ifindex);
 138
 139         return ret;
 140 }
 141
 142 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 143 {
 144         uint8_t val;
 145         int ret, len;
 146
 147         /* Prevent receiving self-origined multicast packets. */
 148         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 149         if (ret < 0)
 150                 flog_err(EC_LIB_SOCKET,
 151                          "can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 152                          top->fd, safe_strerror(errno));
 153
 154         /* Explicitly set multicast ttl to 1 -- endo. */
 155         val = 1;
 156         len = sizeof(val);
 157         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 158                          len);
 159         if (ret < 0)
 160                 flog_err(EC_LIB_SOCKET,
 161                          "can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 162                          top->fd, safe_strerror(errno));
 163 #ifndef GNU_LINUX
 164         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 165          * packet out of ifindex. Below would be used Non Linux system.
 166          */
 167         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 168         if (ret < 0)
 169                 flog_err(EC_LIB_SOCKET,
 170                          "can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 171                          "ifindex %u): %s",
 172                          top->fd, inet_ntoa(p->u.prefix4), ifindex,
 173                          safe_strerror(errno));
 174 #endif
 175
 176         return ret;
 177 }
 178
 179 int ospf_sock_init(struct ospf *ospf)
 180 {
 181         int ospf_sock;
 182         int ret, hincl = 1;
 183         int bufsize = (8 * 1024 * 1024);
 184
 185         /* silently ignore. already done */
 186         if (ospf->fd > 0)
 187                 return -1;
 188
 189         if (ospf->vrf_id == VRF_UNKNOWN) {
 190                 /* silently return since VRF is not ready */
 191                 return -1;
 192         }
 193         frr_elevate_privs(&ospfd_privs) {
 194                 ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
 195                                        ospf->vrf_id, ospf->name);
 196                 if (ospf_sock < 0) {
 197                         flog_err(EC_LIB_SOCKET,
 198                                  "ospf_read_sock_init: socket: %s",
 199                                  safe_strerror(errno));
 200                         exit(1);
 201                 }
 202
 203 #ifdef IP_HDRINCL
 204                 /* we will include IP header with packet */
 205                 ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 206                                  sizeof(hincl));
 207                 if (ret < 0) {
 208                         flog_err(EC_LIB_SOCKET,
 209                                  "Can't set IP_HDRINCL option for fd %d: %s",
 210                                  ospf_sock, safe_strerror(errno));
 211                         close(ospf_sock);
 212                         break;
 213                 }
 214 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 215 #warning "IP_HDRINCL not available on this system"
 216 #warning "using IPTOS_PREC_INTERNETCONTROL"
 217                 ret = setsockopt_ipv4_tos(ospf_sock,
 218                                           IPTOS_PREC_INTERNETCONTROL);
 219                 if (ret < 0) {
 220                         flog_err(EC_LIB_SOCKET,
 221                                  "can't set sockopt IP_TOS %d to socket %d: %s",
 222                                  tos, ospf_sock, safe_strerror(errno));
 223                         close(ospf_sock); /* Prevent sd leak. */
 224                         break;
 225                 }
 226 #else /* !IPTOS_PREC_INTERNETCONTROL */
 227 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 228                 flog_err(EC_LIB_UNAVAILABLE, "IP_HDRINCL option not available");
 229 #endif /* IP_HDRINCL */
 230
 231                 ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 232
 233                 if (ret < 0)
 234                         flog_err(EC_LIB_SOCKET,
 235                                  "Can't set pktinfo option for fd %d",
 236                                  ospf_sock);
 237
 238                 setsockopt_so_sendbuf(ospf_sock, bufsize);
 239                 setsockopt_so_recvbuf(ospf_sock, bufsize);
 240         }
 241
 242         ospf->fd = ospf_sock;
 243         return ret;
 244 }