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("interface %s [%u] join AllSPFRouters Multicast group.",
  62                                    inet_ntoa(p->u.prefix4), ifindex);
  63         }
  64
  65         return ret;
  66 }
  67
  68 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  69                                ifindex_t ifindex)
  70 {
  71         int ret;
  72
  73         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  74                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  75                                         ifindex);
  76         if (ret < 0)
  77                 zlog_warn(
  78                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  79                         "ifindex %u, AllSPFRouters): %s",
  80                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
  81                         safe_strerror(errno));
  82         else {
  83                 if (IS_DEBUG_OSPF_EVENT)
  84                         zlog_debug("interface %s [%u] leave AllSPFRouters Multicast group.",
  85                                    inet_ntoa(p->u.prefix4), ifindex);
  86         }
  87
  88         return ret;
  89 }
  90
  91 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  92 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  93                             ifindex_t ifindex)
  94 {
  95         int ret;
  96
  97         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  98                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
  99                                         ifindex);
 100         if (ret < 0)
 101                 zlog_warn(
 102                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 103                         "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 104                         "on # of multicast group memberships has been exceeded?",
 105                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 106                         safe_strerror(errno));
 107         else
 108                 zlog_debug(
 109                         "interface %s [%u] join AllDRouters Multicast group.",
 110                         inet_ntoa(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                 zlog_warn(
 125                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 126                         "ifindex %u, AllDRouters): %s",
 127                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 128                         safe_strerror(errno));
 129         else
 130                 zlog_debug(
 131                         "interface %s [%u] leave AllDRouters Multicast group.",
 132                         inet_ntoa(p->u.prefix4), ifindex);
 133
 134         return ret;
 135 }
 136
 137 int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
 138 {
 139         u_char val;
 140         int ret, len;
 141
 142         /* Prevent receiving self-origined multicast packets. */
 143         ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
 144         if (ret < 0)
 145                 zlog_warn("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                 zlog_warn("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 155                           top->fd, safe_strerror(errno));
 156 #ifndef GNU_LINUX
 157         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 158          * packet out of ifindex. Below would be used Non Linux system.
 159          */
 160         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 161         if (ret < 0)
 162                 zlog_warn(
 163                         "can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 164                         "ifindex %u): %s",
 165                         top->fd, inet_ntoa(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         if (ospfd_privs.change(ZPRIVS_RAISE)) {
 187                 zlog_err("ospf_sock_init: could not raise privs, %s",
 188                          safe_strerror(errno));
 189         }
 190
 191         ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
 192                                ospf->vrf_id, ospf->name);
 193         if (ospf_sock < 0) {
 194                 int save_errno = errno;
 195
 196                 if (ospfd_privs.change(ZPRIVS_LOWER))
 197                         zlog_err("ospf_sock_init: could not lower privs, %s",
 198                                  safe_strerror(errno));
 199                 zlog_err("ospf_read_sock_init: socket: %s",
 200                          safe_strerror(save_errno));
 201                 exit(1);
 202         }
 203
 204 #ifdef IP_HDRINCL
 205         /* we will include IP header with packet */
 206         ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 207                          sizeof(hincl));
 208         if (ret < 0) {
 209                 int save_errno = errno;
 210
 211                 zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
 212                           ospf_sock, safe_strerror(save_errno));
 213                 close(ospf_sock);
 214                 goto out;
 215         }
 216 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 217 #warning "IP_HDRINCL not available on this system"
 218 #warning "using IPTOS_PREC_INTERNETCONTROL"
 219         ret = setsockopt_ipv4_tos(ospf_sock, IPTOS_PREC_INTERNETCONTROL);
 220         if (ret < 0) {
 221                 int save_errno = errno;
 222
 223                 zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s", tos,
 224                           ospf_sock, safe_strerror(save_errno));
 225                 close(ospf_sock); /* Prevent sd leak. */
 226                 goto out;
 227         }
 228 #else /* !IPTOS_PREC_INTERNETCONTROL */
 229 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 230         zlog_warn("IP_HDRINCL option not available");
 231 #endif /* IP_HDRINCL */
 232
 233         ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 234
 235         if (ret < 0)
 236                 zlog_warn("Can't set pktinfo option for fd %d", ospf_sock);
 237
 238         setsockopt_so_sendbuf(ospf_sock, bufsize);
 239         setsockopt_so_recvbuf(ospf_sock, bufsize);
 240
 241         ospf->fd = ospf_sock;
 242 out:
 243         if (ospfd_privs.change(ZPRIVS_LOWER)) {
 244                 zlog_err("ospf_sock_init: could not lower privs, %s",
 245                          safe_strerror(errno));
 246         }
 247         return ret;
 248 }