eigrpd/eigrp_query.c

   1 /*
   2  * EIGRP Sending and Receiving EIGRP Query Packets.
   3  * Copyright (C) 2013-2014
   4  * Authors:
   5  *   Donnie Savage
   6  *   Jan Janovic
   7  *   Matej Perina
   8  *   Peter Orsag
   9  *   Peter Paluch
  10  *
  11  * This file is part of GNU Zebra.
  12  *
  13  * GNU Zebra is free software; you can redistribute it and/or modify it
  14  * under the terms of the GNU General Public License as published by the
  15  * Free Software Foundation; either version 2, or (at your option) any
  16  * later version.
  17  *
  18  * GNU Zebra is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  * General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  25  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  26  * 02111-1307, USA.
  27  */
  28
  29 #include <zebra.h>
  30
  31 #include "thread.h"
  32 #include "memory.h"
  33 #include "linklist.h"
  34 #include "prefix.h"
  35 #include "if.h"
  36 #include "table.h"
  37 #include "sockunion.h"
  38 #include "stream.h"
  39 #include "log.h"
  40 #include "sockopt.h"
  41 #include "checksum.h"
  42 #include "md5.h"
  43 #include "vty.h"
  44
  45 #include "eigrpd/eigrp_structs.h"
  46 #include "eigrpd/eigrpd.h"
  47 #include "eigrpd/eigrp_interface.h"
  48 #include "eigrpd/eigrp_neighbor.h"
  49 #include "eigrpd/eigrp_packet.h"
  50 #include "eigrpd/eigrp_zebra.h"
  51 #include "eigrpd/eigrp_vty.h"
  52 #include "eigrpd/eigrp_dump.h"
  53 #include "eigrpd/eigrp_macros.h"
  54 #include "eigrpd/eigrp_topology.h"
  55 #include "eigrpd/eigrp_fsm.h"
  56 #include "eigrpd/eigrp_memory.h"
  57
  58 u_int32_t
  59 eigrp_query_send_all (struct eigrp *eigrp)
  60 {
  61   struct eigrp_interface *iface;
  62   struct listnode *node, *node2, *nnode2;
  63   struct eigrp_prefix_entry *pe;
  64   u_int32_t counter;
  65
  66   if (eigrp == NULL)
  67     {
  68       zlog_debug("EIGRP Routing Process not enabled");
  69       return 0;
  70     }
  71
  72   counter=0;
  73   for (ALL_LIST_ELEMENTS_RO(eigrp->eiflist, node, iface))
  74     {
  75       eigrp_send_query(iface);
  76       counter++;
  77     }
  78
  79   for (ALL_LIST_ELEMENTS(eigrp->topology_changes_internalIPV4, node2, nnode2, pe))
  80     {
  81       if(pe->req_action & EIGRP_FSM_NEED_QUERY)
  82         {
  83           pe->req_action &= ~EIGRP_FSM_NEED_QUERY;
  84           listnode_delete(eigrp->topology_changes_internalIPV4, pe);
  85         }
  86     }
  87
  88   return counter;
  89 }
  90
  91 /*EIGRP QUERY read function*/
  92 void
  93 eigrp_query_receive (struct eigrp *eigrp, struct ip *iph, struct eigrp_header *eigrph,
  94                      struct stream * s, struct eigrp_interface *ei, int size)
  95 {
  96   struct eigrp_neighbor *nbr;
  97   struct TLV_IPv4_Internal_type *tlv;
  98
  99   u_int16_t type;
 100
 101   /* increment statistics. */
 102   ei->query_in++;
 103
 104   /* get neighbor struct */
 105   nbr = eigrp_nbr_get(ei, eigrph, iph);
 106
 107   /* neighbor must be valid, eigrp_nbr_get creates if none existed */
 108   assert(nbr);
 109
 110   nbr->recv_sequence_number = ntohl(eigrph->sequence);
 111
 112   while (s->endp > s->getp)
 113     {
 114       type = stream_getw(s);
 115       if (type == EIGRP_TLV_IPv4_INT)
 116         {
 117           stream_set_getp(s, s->getp - sizeof(u_int16_t));
 118
 119           tlv = eigrp_read_ipv4_tlv(s);
 120
 121           struct prefix_ipv4 *dest_addr;
 122           dest_addr = prefix_ipv4_new();
 123           dest_addr->prefix = tlv->destination;
 124           dest_addr->prefixlen = tlv->prefix_length;
 125           struct eigrp_prefix_entry *dest = eigrp_topology_table_lookup_ipv4(
 126               eigrp->topology_table, dest_addr);
 127
 128           /* If the destination exists (it should, but one never know)*/
 129           if (dest != NULL)
 130             {
 131               struct eigrp_fsm_action_message *msg;
 132               msg = XCALLOC(MTYPE_EIGRP_FSM_MSG,
 133                   sizeof(struct eigrp_fsm_action_message));
 134               struct eigrp_neighbor_entry *entry = eigrp_prefix_entry_lookup(
 135                   dest->entries, nbr);
 136               msg->packet_type = EIGRP_OPC_QUERY;
 137               msg->eigrp = eigrp;
 138               msg->data_type = EIGRP_TLV_IPv4_INT;
 139               msg->adv_router = nbr;
 140               msg->data.ipv4_int_type = tlv;
 141               msg->entry = entry;
 142               msg->prefix = dest;
 143               int event = eigrp_get_fsm_event(msg);
 144               eigrp_fsm_event(msg, event);
 145             }
 146           eigrp_IPv4_InternalTLV_free (tlv);
 147         }
 148     }
 149   eigrp_hello_send_ack(nbr);
 150   eigrp_query_send_all(eigrp);
 151   eigrp_update_send_all(eigrp,nbr->ei);
 152 }
 153
 154 void
 155 eigrp_send_query (struct eigrp_interface *ei)
 156 {
 157   struct eigrp_packet *ep;
 158   u_int16_t length = EIGRP_HEADER_LEN;
 159   struct listnode *node, *nnode, *node2, *nnode2;
 160   struct eigrp_neighbor *nbr;
 161   struct eigrp_prefix_entry *pe;
 162   char has_tlv;
 163
 164   ep = eigrp_packet_new(ei->ifp->mtu);
 165
 166   /* Prepare EIGRP INIT UPDATE header */
 167   eigrp_packet_header_init(EIGRP_OPC_QUERY, ei, ep->s, 0,
 168                            ei->eigrp->sequence_number, 0);
 169
 170   // encode Authentication TLV, if needed
 171   if((IF_DEF_PARAMS (ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) && (IF_DEF_PARAMS (ei->ifp)->auth_keychain != NULL))
 172     {
 173       length += eigrp_add_authTLV_MD5_to_stream(ep->s,ei);
 174     }
 175
 176   has_tlv = 0;
 177   for (ALL_LIST_ELEMENTS(ei->eigrp->topology_changes_internalIPV4, node, nnode, pe))
 178     {
 179       if(pe->req_action & EIGRP_FSM_NEED_QUERY)
 180         {
 181           length += eigrp_add_internalTLV_to_stream(ep->s, pe);
 182           for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr))
 183             {
 184                   if(nbr->state == EIGRP_NEIGHBOR_UP)
 185                   {
 186                           listnode_add(pe->rij, nbr);
 187                   has_tlv = 1;
 188                   }
 189             }
 190         }
 191     }
 192
 193   if(!has_tlv)
 194     {
 195       eigrp_packet_free(ep);
 196       return;
 197     }
 198
 199   if((IF_DEF_PARAMS (ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) && (IF_DEF_PARAMS (ei->ifp)->auth_keychain != NULL))
 200     {
 201       eigrp_make_md5_digest(ei,ep->s, EIGRP_AUTH_UPDATE_FLAG);
 202     }
 203
 204   /* EIGRP Checksum */
 205     eigrp_packet_checksum(ei, ep->s, length);
 206
 207     ep->length = length;
 208     ep->dst.s_addr = htonl(EIGRP_MULTICAST_ADDRESS);
 209
 210     /*This ack number we await from neighbor*/
 211     ep->sequence_number = ei->eigrp->sequence_number;
 212
 213     for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr))
 214       {
 215         if (nbr->state == EIGRP_NEIGHBOR_UP)
 216           {
 217             /*Put packet to retransmission queue*/
 218             eigrp_fifo_push_head(nbr->retrans_queue, ep);
 219
 220             if (nbr->retrans_queue->count == 1)
 221               {
 222                 eigrp_send_packet_reliably(nbr);
 223               }
 224           }
 225       }
 226 }