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 #include "ospfd/ospf_dump.h"
  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                 if (IS_DEBUG_OSPF_EVENT)
  61                         zlog_debug(
  62                                 "interface %s [%u] join AllSPFRouters Multicast group.",
  63                                 inet_ntoa(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                 zlog_warn(
  79                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  80                         "ifindex %u, AllSPFRouters): %s",
  81                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  82                         safe_strerror(errno));
  83         else {
  84                 if (IS_DEBUG_OSPF_EVENT)
  85                         zlog_debug(
  86                                 "interface %s [%u] leave AllSPFRouters Multicast group.",
  87                                 inet_ntoa(p->u.prefix4), ifindex);
  88         }
  89
  90         return ret;
  91 }
  92
  93 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  94 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  95                             ifindex_t ifindex)
  96 {
  97         int ret;
  98
  99         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
 100                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 101                                         ifindex);
 102         if (ret < 0)
 103                 zlog_warn(
 104                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 105                         "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 106                         "on # of multicast group memberships has been exceeded?",
 107                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 108                         safe_strerror(errno));
 109         else
 110                 zlog_debug(
 111                         "interface %s [%u] join AllDRouters Multicast group.",
 112                         inet_ntoa(p->u.prefix4), ifindex);
 113
 114         return ret;
 115 }
 116
 117 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 118                              ifindex_t ifindex)
 119 {
 120         int ret;
 121
 122         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 123                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 124                                         ifindex);
 125         if (ret < 0)
 126                 zlog_warn(
 127                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 128                         "ifindex %u, AllDRouters): %s",
 129                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 130                         safe_strerror(errno));
 131         else
 132                 zlog_debug(
 133                         "interface %s [%u] leave AllDRouters Multicast group.",
 134                         inet_ntoa(p->u.prefix4), ifindex);
 135
 136         return ret;
 137 }
 138
 139 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 140 {
 141         u_char val;
 142         int ret, len;
 143
 144         /* Prevent receiving self-origined multicast packets. */
 145         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 146         if (ret < 0)
 147                 zlog_warn("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 148                           top->fd, safe_strerror(errno));
 149
 150         /* Explicitly set multicast ttl to 1 -- endo. */
 151         val = 1;
 152         len = sizeof(val);
 153         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 154                          len);
 155         if (ret < 0)
 156                 zlog_warn("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 157                           top->fd, safe_strerror(errno));
 158 #ifndef GNU_LINUX
 159         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 160          * packet out of ifindex. Below would be used Non Linux system.
 161          */
 162         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 163         if (ret < 0)
 164                 zlog_warn(
 165                         "can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 166                         "ifindex %u): %s",
 167                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 168                         safe_strerror(errno));
 169 #endif
 170
 171         return ret;
 172 }
 173
 174 int ospf_sock_init(struct ospf *ospf)
 175 {
 176         int ospf_sock;
 177         int ret, hincl = 1;
 178         int bufsize = (8 * 1024 * 1024);
 179
 180         /* silently ignore. already done */
 181         if (ospf->fd > 0)
 182                 return -1;
 183
 184         if (ospf->vrf_id == VRF_UNKNOWN) {
 185                 /* silently return since VRF is not ready */
 186                 return -1;
 187         }
 188         if (ospfd_privs.change(ZPRIVS_RAISE)) {
 189                 zlog_err("ospf_sock_init: could not raise privs, %s",
 190                          safe_strerror(errno));
 191         }
 192
 193         ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP, ospf->vrf_id,
 194                                ospf->name);
 195         if (ospf_sock < 0) {
 196                 int save_errno = errno;
 197
 198                 if (ospfd_privs.change(ZPRIVS_LOWER))
 199                         zlog_err("ospf_sock_init: could not lower privs, %s",
 200                                  safe_strerror(errno));
 201                 zlog_err("ospf_read_sock_init: socket: %s",
 202                          safe_strerror(save_errno));
 203                 exit(1);
 204         }
 205
 206 #ifdef IP_HDRINCL
 207         /* we will include IP header with packet */
 208         ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 209                          sizeof(hincl));
 210         if (ret < 0) {
 211                 int save_errno = errno;
 212
 213                 zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
 214                           ospf_sock, safe_strerror(save_errno));
 215                 close(ospf_sock);
 216                 goto out;
 217         }
 218 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 219 #warning "IP_HDRINCL not available on this system"
 220 #warning "using IPTOS_PREC_INTERNETCONTROL"
 221         ret = setsockopt_ipv4_tos(ospf_sock, IPTOS_PREC_INTERNETCONTROL);
 222         if (ret < 0) {
 223                 int save_errno = errno;
 224
 225                 zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s", tos,
 226                           ospf_sock, safe_strerror(save_errno));
 227                 close(ospf_sock); /* Prevent sd leak. */
 228                 goto out;
 229         }
 230 #else /* !IPTOS_PREC_INTERNETCONTROL */
 231 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 232         zlog_warn("IP_HDRINCL option not available");
 233 #endif /* IP_HDRINCL */
 234
 235         ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 236
 237         if (ret < 0)
 238                 zlog_warn("Can't set pktinfo option for fd %d", ospf_sock);
 239
 240         setsockopt_so_sendbuf(ospf_sock, bufsize);
 241         setsockopt_so_recvbuf(ospf_sock, bufsize);
 242
 243         ospf->fd = ospf_sock;
 244 out:
 245         if (ospfd_privs.change(ZPRIVS_LOWER)) {
 246                 zlog_err("ospf_sock_init: could not lower privs, %s",
 247                          safe_strerror(errno));
 248         }
 249         return ret;
 250 }