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 along
  24  * with this program; see the file COPYING; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  26  */
  27
  28 #include <zebra.h>
  29
  30 #include "thread.h"
  31 #include "memory.h"
  32 #include "linklist.h"
  33 #include "prefix.h"
  34 #include "if.h"
  35 #include "table.h"
  36 #include "sockunion.h"
  37 #include "stream.h"
  38 #include "log.h"
  39 #include "sockopt.h"
  40 #include "checksum.h"
  41 #include "md5.h"
  42 #include "vty.h"
  43
  44 #include "eigrpd/eigrp_structs.h"
  45 #include "eigrpd/eigrpd.h"
  46 #include "eigrpd/eigrp_interface.h"
  47 #include "eigrpd/eigrp_neighbor.h"
  48 #include "eigrpd/eigrp_packet.h"
  49 #include "eigrpd/eigrp_zebra.h"
  50 #include "eigrpd/eigrp_vty.h"
  51 #include "eigrpd/eigrp_dump.h"
  52 #include "eigrpd/eigrp_macros.h"
  53 #include "eigrpd/eigrp_topology.h"
  54 #include "eigrpd/eigrp_fsm.h"
  55 #include "eigrpd/eigrp_memory.h"
  56
  57 u_int32_t eigrp_query_send_all(struct eigrp *eigrp)
  58 {
  59         struct eigrp_interface *iface;
  60         struct listnode *node, *node2, *nnode2;
  61         struct eigrp_prefix_entry *pe;
  62         u_int32_t counter;
  63
  64         if (eigrp == NULL) {
  65                 zlog_debug("EIGRP Routing Process not enabled");
  66                 return 0;
  67         }
  68
  69         counter = 0;
  70         for (ALL_LIST_ELEMENTS_RO(eigrp->eiflist, node, iface)) {
  71                 eigrp_send_query(iface);
  72                 counter++;
  73         }
  74
  75         for (ALL_LIST_ELEMENTS(eigrp->topology_changes_internalIPV4, node2,
  76                                nnode2, pe)) {
  77                 if (pe->req_action & EIGRP_FSM_NEED_QUERY) {
  78                         pe->req_action &= ~EIGRP_FSM_NEED_QUERY;
  79                         listnode_delete(eigrp->topology_changes_internalIPV4,
  80                                         pe);
  81                 }
  82         }
  83
  84         return counter;
  85 }
  86
  87 /*EIGRP QUERY read function*/
  88 void eigrp_query_receive(struct eigrp *eigrp, struct ip *iph,
  89                          struct eigrp_header *eigrph, struct stream *s,
  90                          struct eigrp_interface *ei, int size)
  91 {
  92         struct eigrp_neighbor *nbr;
  93         struct TLV_IPv4_Internal_type *tlv;
  94
  95         u_int16_t type;
  96
  97         /* increment statistics. */
  98         ei->query_in++;
  99
 100         /* get neighbor struct */
 101         nbr = eigrp_nbr_get(ei, eigrph, iph);
 102
 103         /* neighbor must be valid, eigrp_nbr_get creates if none existed */
 104         assert(nbr);
 105
 106         nbr->recv_sequence_number = ntohl(eigrph->sequence);
 107
 108         while (s->endp > s->getp) {
 109                 type = stream_getw(s);
 110                 if (type == EIGRP_TLV_IPv4_INT) {
 111                         struct prefix_ipv4 dest_addr;
 112
 113                         stream_set_getp(s, s->getp - sizeof(u_int16_t));
 114
 115                         tlv = eigrp_read_ipv4_tlv(s);
 116
 117                         dest_addr.family = AF_INET;
 118                         dest_addr.prefix = tlv->destination;
 119                         dest_addr.prefixlen = tlv->prefix_length;
 120                         struct eigrp_prefix_entry *dest =
 121                                 eigrp_topology_table_lookup_ipv4(
 122                                         eigrp->topology_table, &dest_addr);
 123
 124                         /* If the destination exists (it should, but one never
 125                          * know)*/
 126                         if (dest != NULL) {
 127                                 struct eigrp_fsm_action_message *msg;
 128                                 msg = XCALLOC(MTYPE_EIGRP_FSM_MSG,
 129                                               sizeof(struct
 130                                                      eigrp_fsm_action_message));
 131                                 struct eigrp_neighbor_entry *entry =
 132                                         eigrp_prefix_entry_lookup(dest->entries,
 133                                                                   nbr);
 134                                 msg->packet_type = EIGRP_OPC_QUERY;
 135                                 msg->eigrp = eigrp;
 136                                 msg->data_type = EIGRP_TLV_IPv4_INT;
 137                                 msg->adv_router = nbr;
 138                                 msg->data.ipv4_int_type = tlv;
 139                                 msg->entry = entry;
 140                                 msg->prefix = dest;
 141                                 int event = eigrp_get_fsm_event(msg);
 142                                 eigrp_fsm_event(msg, event);
 143                         }
 144                         eigrp_IPv4_InternalTLV_free(tlv);
 145                 }
 146         }
 147         eigrp_hello_send_ack(nbr);
 148         eigrp_query_send_all(eigrp);
 149         eigrp_update_send_all(eigrp, nbr->ei);
 150 }
 151
 152 void eigrp_send_query(struct eigrp_interface *ei)
 153 {
 154         struct eigrp_packet *ep;
 155         u_int16_t length = EIGRP_HEADER_LEN;
 156         struct listnode *node, *nnode, *node2, *nnode2;
 157         struct eigrp_neighbor *nbr;
 158         struct eigrp_prefix_entry *pe;
 159         char has_tlv;
 160         bool ep_saved = false;
 161
 162         ep = eigrp_packet_new(ei->ifp->mtu);
 163
 164         /* Prepare EIGRP INIT UPDATE header */
 165         eigrp_packet_header_init(EIGRP_OPC_QUERY, ei, ep->s, 0,
 166                                  ei->eigrp->sequence_number, 0);
 167
 168         // encode Authentication TLV, if needed
 169         if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
 170             && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {
 171                 length += eigrp_add_authTLV_MD5_to_stream(ep->s, ei);
 172         }
 173
 174         has_tlv = 0;
 175         for (ALL_LIST_ELEMENTS(ei->eigrp->topology_changes_internalIPV4, node,
 176                                nnode, pe)) {
 177                 if (pe->req_action & EIGRP_FSM_NEED_QUERY) {
 178                         length += eigrp_add_internalTLV_to_stream(ep->s, pe);
 179                         for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr)) {
 180                                 if (nbr->state == EIGRP_NEIGHBOR_UP) {
 181                                         listnode_add(pe->rij, nbr);
 182                                         has_tlv = 1;
 183                                 }
 184                         }
 185                 }
 186         }
 187
 188         if (!has_tlv) {
 189                 eigrp_packet_free(ep);
 190                 return;
 191         }
 192
 193         if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
 194             && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {
 195                 eigrp_make_md5_digest(ei, ep->s, EIGRP_AUTH_UPDATE_FLAG);
 196         }
 197
 198         /* EIGRP Checksum */
 199         eigrp_packet_checksum(ei, ep->s, length);
 200
 201         ep->length = length;
 202         ep->dst.s_addr = htonl(EIGRP_MULTICAST_ADDRESS);
 203
 204         /*This ack number we await from neighbor*/
 205         ep->sequence_number = ei->eigrp->sequence_number;
 206
 207         for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr)) {
 208                 if (nbr->state == EIGRP_NEIGHBOR_UP) {
 209                         /*Put packet to retransmission queue*/
 210                         eigrp_fifo_push_head(nbr->retrans_queue, ep);
 211                         ep_saved = true;
 212
 213                         if (nbr->retrans_queue->count == 1) {
 214                                 eigrp_send_packet_reliably(nbr);
 215                         }
 216                 }
 217         }
 218
 219         if (!ep_saved)
 220                 eigrp_packet_free(ep);
 221 }