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 #include "ospfd/ospf_dump.h"
  45
  46
  47
  48 /* Join to the OSPF ALL SPF ROUTERS multicast group. */
  49 int
  50 ospf_if_add_allspfrouters (struct ospf *top, struct prefix *p,
  51                            unsigned int ifindex)
  52 {
  53   int ret;
  54
  55   ret = setsockopt_ipv4_multicast (top->fd, IP_ADD_MEMBERSHIP,
  56                                    htonl (OSPF_ALLSPFROUTERS),
  57                                    ifindex);
  58   if (ret < 0)
  59     zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
  60                "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
  61                "on # of multicast group memberships has been exceeded?",
  62                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
  63   else
  64     zlog_debug ("interface %s [%u] join AllSPFRouters Multicast group.",
  65                inet_ntoa (p->u.prefix4), ifindex);
  66
  67   return ret;
  68 }
  69
  70 int
  71 ospf_if_drop_allspfrouters (struct ospf *top, struct prefix *p,
  72                             unsigned int ifindex)
  73 {
  74   int ret;
  75
  76   ret = setsockopt_ipv4_multicast (top->fd, IP_DROP_MEMBERSHIP,
  77                                    htonl (OSPF_ALLSPFROUTERS),
  78                                    ifindex);
  79   if (ret < 0)
  80     zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
  81                "ifindex %u, AllSPFRouters): %s",
  82                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
  83   else
  84     zlog_debug ("interface %s [%u] leave AllSPFRouters Multicast group.",
  85                 inet_ntoa (p->u.prefix4), ifindex);
  86
  87   return ret;
  88 }
  89
  90 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  91 int
  92 ospf_if_add_alldrouters (struct ospf *top, struct prefix *p, unsigned int
  93                          ifindex)
  94 {
  95   int ret;
  96
  97   ret = setsockopt_ipv4_multicast (top->fd, IP_ADD_MEMBERSHIP,
  98                                    htonl (OSPF_ALLDROUTERS),
  99                                    ifindex);
 100   if (ret < 0)
 101     zlog_warn ("can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 102                "ifindex %u, AllDRouters): %s; perhaps a kernel limit "
 103                "on # of multicast group memberships has been exceeded?",
 104                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
 105   else
 106     zlog_debug ("interface %s [%u] join AllDRouters Multicast group.",
 107                 inet_ntoa (p->u.prefix4), ifindex);
 108
 109   return ret;
 110 }
 111
 112 int
 113 ospf_if_drop_alldrouters (struct ospf *top, struct prefix *p, unsigned int
 114                           ifindex)
 115 {
 116   int ret;
 117
 118   ret = setsockopt_ipv4_multicast (top->fd, IP_DROP_MEMBERSHIP,
 119                                    htonl (OSPF_ALLDROUTERS),
 120                                    ifindex);
 121   if (ret < 0)
 122     zlog_warn ("can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 123                "ifindex %u, AllDRouters): %s",
 124                top->fd, inet_ntoa(p->u.prefix4), ifindex, safe_strerror(errno));
 125   else
 126     zlog_debug ("interface %s [%u] leave AllDRouters Multicast group.",
 127                 inet_ntoa (p->u.prefix4), ifindex);
 128
 129   return ret;
 130 }
 131
 132 int
 133 ospf_if_ipmulticast (struct ospf *top, struct prefix *p, unsigned int ifindex)
 134 {
 135   u_char val;
 136   int ret, len;
 137
 138   val = 0;
 139   len = sizeof (val);
 140
 141   /* Prevent receiving self-origined multicast packets. */
 142   ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val, len);
 143   if (ret < 0)
 144     zlog_warn ("can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 145                top->fd, safe_strerror(errno));
 146
 147   /* Explicitly set multicast ttl to 1 -- endo. */
 148   val = 1;
 149   ret = setsockopt (top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val, len);
 150   if (ret < 0)
 151     zlog_warn ("can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 152                top->fd, safe_strerror (errno));
 153
 154   ret = setsockopt_ipv4_multicast_if (top->fd, 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   int ret, hincl = 1;
 168
 169   if ( ospfd_privs.change (ZPRIVS_RAISE) )
 170     zlog_err ("ospf_sock_init: could not raise privs, %s",
 171                safe_strerror (errno) );
 172
 173   ospf_sock = socket (AF_INET, SOCK_RAW, IPPROTO_OSPFIGP);
 174   if (ospf_sock < 0)
 175     {
 176       int save_errno = errno;
 177       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 178         zlog_err ("ospf_sock_init: could not lower privs, %s",
 179                    safe_strerror (errno) );
 180       zlog_err ("ospf_read_sock_init: socket: %s", safe_strerror (save_errno));
 181       exit(1);
 182     }
 183
 184 #ifdef IP_HDRINCL
 185   /* we will include IP header with packet */
 186   ret = setsockopt (ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl, sizeof (hincl));
 187   if (ret < 0)
 188     {
 189       int save_errno = errno;
 190       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 191         zlog_err ("ospf_sock_init: could not lower privs, %s",
 192                    safe_strerror (errno) );
 193       zlog_warn ("Can't set IP_HDRINCL option for fd %d: %s",
 194                  ospf_sock, safe_strerror(save_errno));
 195     }
 196 #elif defined (IPTOS_PREC_INTERNETCONTROL)
 197 #warning "IP_HDRINCL not available on this system"
 198 #warning "using IPTOS_PREC_INTERNETCONTROL"
 199   ret = setsockopt_ipv4_tos(ospf_sock, IPTOS_PREC_INTERNETCONTROL);
 200   if (ret < 0)
 201     {
 202       int save_errno = errno;
 203       if ( ospfd_privs.change (ZPRIVS_LOWER) )
 204         zlog_err ("ospf_sock_init: could not lower privs, %s",
 205                    safe_strerror (errno) );
 206       zlog_warn ("can't set sockopt IP_TOS %d to socket %d: %s",
 207                  tos, ospf_sock, safe_strerror(save_errno));
 208       close (ospf_sock);        /* Prevent sd leak. */
 209       return ret;
 210     }
 211 #else /* !IPTOS_PREC_INTERNETCONTROL */
 212 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 213   zlog_warn ("IP_HDRINCL option not available");
 214 #endif /* IP_HDRINCL */
 215
 216   ret = setsockopt_ifindex (AF_INET, ospf_sock, 1);
 217
 218   if (ret < 0)
 219      zlog_warn ("Can't set pktinfo option for fd %d", ospf_sock);
 220
 221   if (ospfd_privs.change (ZPRIVS_LOWER))
 222     {
 223       zlog_err ("ospf_sock_init: could not lower privs, %s",
 224                safe_strerror (errno) );
 225     }
 226
 227   return ospf_sock;
 228 }
 229
 230 void
 231 ospf_adjust_sndbuflen (struct ospf * ospf, int buflen)
 232 {
 233   int ret, newbuflen;
 234   /* Check if any work has to be done at all. */
 235   if (ospf->maxsndbuflen >= buflen)
 236     return;
 237   if (IS_DEBUG_OSPF (zebra, ZEBRA_INTERFACE))
 238     zlog_debug ("%s: adjusting OSPF send buffer size to %d",
 239       __func__, buflen);
 240   if (ospfd_privs.change (ZPRIVS_RAISE))
 241     zlog_err ("%s: could not raise privs, %s", __func__,
 242       safe_strerror (errno));
 243   /* Now we try to set SO_SNDBUF to what our caller has requested
 244    * (the MTU of a newly added interface). However, if the OS has
 245    * truncated the actual buffer size to somewhat less size, try
 246    * to detect it and update our records appropriately. The OS
 247    * may allocate more buffer space, than requested, this isn't
 248    * a error.
 249    */
 250   ret = setsockopt_so_sendbuf (ospf->fd, buflen);
 251   newbuflen = getsockopt_so_sendbuf (ospf->fd);
 252   if (ret < 0 || newbuflen < buflen)
 253     zlog_warn ("%s: tried to set SO_SNDBUF to %d, but got %d",
 254       __func__, buflen, newbuflen);
 255   if (newbuflen >= 0)
 256     ospf->maxsndbuflen = newbuflen;
 257   else
 258     zlog_warn ("%s: failed to get SO_SNDBUF", __func__);
 259   if (ospfd_privs.change (ZPRIVS_LOWER))
 260     zlog_err ("%s: could not lower privs, %s", __func__,
 261       safe_strerror (errno));
 262 }