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
  18  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  */
  22
  23 #include <zebra.h>
  24
  25 #include "thread.h"
  26 #include "linklist.h"
  27 #include "prefix.h"
  28 #include "if.h"
  29 #include "sockunion.h"
  30 #include "log.h"
  31 #include "sockopt.h"
  32 #include "privs.h"
  33
  34 extern struct zebra_privs_t ospfd_privs;
  35
  36 #include "ospfd/ospfd.h"
  37 #include "ospfd/ospf_network.h"
  38 #include "ospfd/ospf_interface.h"
  39 #include "ospfd/ospf_asbr.h"
  40 #include "ospfd/ospf_lsa.h"
  41 #include "ospfd/ospf_lsdb.h"
  42 #include "ospfd/ospf_neighbor.h"
  43 #include "ospfd/ospf_packet.h"
  44
  45
  46
  47 /* Join to the OSPF ALL SPF ROUTERS multicast group. */
  48 int
  49 ospf_if_add_allspfrouters (struct ospf *top, struct prefix *p,
  50                            unsigned int ifindex)
  51 {
  52   int ret;
  53
  54   ret = setsockopt_multicast_ipv4 (top->fd, IP_ADD_MEMBERSHIP,
  55                                    p->u.prefix4, htonl (OSPF_ALLSPFROUTERS),
  56                                    ifindex);
  57   if (ret < 0)
  58     zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
  59                "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
  60                "on # of multicast group memberships has been exceeded?",
  61                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
  62   else
  63     zlog_info ("interface %s [%u] join AllSPFRouters Multicast group.",
  64                inet_ntoa (p->u.prefix4), ifindex);
  65
  66   return ret;
  67 }
  68
  69 int
  70 ospf_if_drop_allspfrouters (struct ospf *top, struct prefix *p,
  71                             unsigned int ifindex)
  72 {
  73   int ret;
  74
  75   ret = setsockopt_multicast_ipv4 (top->fd, IP_DROP_MEMBERSHIP,
  76                                    p->u.prefix4, htonl (OSPF_ALLSPFROUTERS),
  77                                    ifindex);
  78   if (ret < 0)
  79     zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  80                "ifindex %u, AllSPFRouters): %s",
  81                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
  82   else
  83     zlog_info ("interface %s [%u] leave AllSPFRouters Multicast group.",
  84                inet_ntoa (p->u.prefix4), ifindex);
  85
  86   return ret;
  87 }
  88
  89 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  90 int
  91 ospf_if_add_alldrouters (struct ospf *top, struct prefix *p, unsigned int
  92                          ifindex)
  93 {
  94   int ret;
  95
  96   ret = setsockopt_multicast_ipv4 (top->fd, IP_ADD_MEMBERSHIP,
  97                                    p->u.prefix4, htonl (OSPF_ALLDROUTERS),
  98                                    ifindex);
  99   if (ret < 0)
 100     zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 101                "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 102                "on # of multicast group memberships has been exceeded?",
 103                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
 104   else
 105     zlog_info ("interface %s [%u] join AllDRouters Multicast group.",
 106                inet_ntoa (p->u.prefix4), ifindex);
 107
 108   return ret;
 109 }
 110
 111 int
 112 ospf_if_drop_alldrouters (struct ospf *top, struct prefix *p, unsigned int
 113                           ifindex)
 114 {
 115   int ret;
 116
 117   ret = setsockopt_multicast_ipv4 (top->fd, IP_DROP_MEMBERSHIP,
 118                                    p->u.prefix4, htonl (OSPF_ALLDROUTERS),
 119                                    ifindex);
 120   if (ret < 0)
 121     zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 122                "ifindex %u, AllDRouters): %s",
 123                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
 124   else
 125     zlog_info ("interface %s [%u] leave AllDRouters Multicast group.",
 126                inet_ntoa (p->u.prefix4), ifindex);
 127
 128   return ret;
 129 }
 130
 131 int
 132 ospf_if_ipmulticast (struct ospf *top, struct prefix *p, unsigned int ifindex)
 133 {
 134   u_char val;
 135   int ret, len;
 136
 137   val = 0;
 138   len = sizeof (val);
 139
 140   /* Prevent receiving self-origined multicast packets. */
 141   ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val, len);
 142   if (ret < 0)
 143     zlog_warn ("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 144                top->fd, safe_strerror(errno));
 145
 146   /* Explicitly set multicast ttl to 1 -- endo. */
 147   val = 1;
 148   ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val, len);
 149   if (ret < 0)
 150     zlog_warn ("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 151                top->fd, safe_strerror (errno));
 152
 153   ret = setsockopt_multicast_ipv4 (top->fd, IP_MULTICAST_IF,
 154                                    p->u.prefix4, 0, ifindex);
 155   if (ret < 0)
 156     zlog_warn("can't setsockopt IP_MULTICAST_IF(fd %d, addr %s, "
 157               "ifindex %u): %s",
 158               top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
 159
 160   return ret;
 161 }
 162
 163 int
 164 ospf_sock_init (void)
 165 {
 166   int ospf_sock;
 167   /*
 168    * XXX warning: unused variable `tos'
 169    * tos should be ifdefed similarly to usage
 170    */
 171   int ret, tos, hincl = 1;
 172
 173   if ( ospfd_privs.change (ZPRIVS_RAISE) )
 174     zlog_err ("ospf_sock_init: could not raise privs, %s",
 175                safe_strerror (errno) );
 176
 177   ospf_sock = socket (AF_INET, SOCK_RAW, IPPROTO_OSPFIGP);
 178   if (ospf_sock < 0)
 179     {
 180       int save_errno = errno;
 181       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 182         zlog_err ("ospf_sock_init: could not lower privs, %s",
 183                    safe_strerror (errno) );
 184       zlog_err ("ospf_read_sock_init: socket: %s", safe_strerror (save_errno));
 185       exit(1);
 186     }
 187
 188 #ifdef IP_HDRINCL
 189   /* we will include IP header with packet */
 190   ret = setsockopt (ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl, sizeof (hincl));
 191   if (ret < 0)
 192     {
 193       int save_errno = errno;
 194       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 195         zlog_err ("ospf_sock_init: could not lower privs, %s",
 196                    safe_strerror (errno) );
 197       zlog_warn ("Can't set IP_HDRINCL option for fd %d: %s",
 198                  ospf_sock, safe_strerror(save_errno));
 199     }
 200 #elif defined (IPTOS_PREC_INTERNETCONTROL)
 201 #warning "IP_HDRINCL not available on this system"
 202 #warning "using IPTOS_PREC_INTERNETCONTROL"
 203   /* Set precedence field. */
 204   tos = IPTOS_PREC_INTERNETCONTROL;
 205   ret = setsockopt (ospf_sock, IPPROTO_IP, IP_TOS,
 206                     (char *) &tos, sizeof (int));
 207   if (ret < 0)
 208     {
 209       int save_errno = errno;
 210       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 211         zlog_err ("ospf_sock_init: could not lower privs, %s",
 212                    safe_strerror (errno) );
 213       zlog_warn ("can't set sockopt IP_TOS %d to socket %d: %s",
 214                  tos, ospf_sock, safe_strerror(save_errno));
 215       close (ospf_sock);        /* Prevent sd leak. */
 216       return ret;
 217     }
 218 #else /* !IPTOS_PREC_INTERNETCONTROL */
 219 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 220   zlog_warn ("IP_HDRINCL option not available");
 221 #endif /* IP_HDRINCL */
 222
 223   ret = setsockopt_ifindex (AF_INET, ospf_sock, 1);
 224
 225   if (ret < 0)
 226      zlog_warn ("Can't set pktinfo option for fd %d", ospf_sock);
 227
 228   if (ospfd_privs.change (ZPRIVS_LOWER))
 229     {
 230       zlog_err ("ospf_sock_init: could not lower privs, %s",
 231                safe_strerror (errno) );
 232     }
 233
 234   return ospf_sock;
 235 }