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 uint32_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         uint32_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         struct prefix dest_addr;
  95
  96         uint16_t type;
  97         uint16_t length;
  98
  99         /* increment statistics. */
 100         ei->query_in++;
 101
 102         /* get neighbor struct */
 103         nbr = eigrp_nbr_get(ei, eigrph, iph);
 104
 105         /* neighbor must be valid, eigrp_nbr_get creates if none existed */
 106         assert(nbr);
 107
 108         nbr->recv_sequence_number = ntohl(eigrph->sequence);
 109
 110         while (s->endp > s->getp) {
 111                 type = stream_getw(s);
 112                 switch (type) {
 113                 case EIGRP_TLV_IPv4_INT:
 114                         stream_set_getp(s, s->getp - sizeof(uint16_t));
 115
 116                         tlv = eigrp_read_ipv4_tlv(s);
 117
 118                         dest_addr.family = AF_INET;
 119                         dest_addr.u.prefix4 = tlv->destination;
 120                         dest_addr.prefixlen = tlv->prefix_length;
 121                         struct eigrp_prefix_entry *dest =
 122                                 eigrp_topology_table_lookup_ipv4(
 123                                         eigrp->topology_table, &dest_addr);
 124
 125                         /* If the destination exists (it should, but one never
 126                          * know)*/
 127                         if (dest != NULL) {
 128                                 struct eigrp_fsm_action_message msg;
 129                                 struct eigrp_nexthop_entry *entry =
 130                                         eigrp_prefix_entry_lookup(dest->entries,
 131                                                                   nbr);
 132                                 msg.packet_type = EIGRP_OPC_QUERY;
 133                                 msg.eigrp = eigrp;
 134                                 msg.data_type = EIGRP_INT;
 135                                 msg.adv_router = nbr;
 136                                 msg.metrics = tlv->metric;
 137                                 msg.entry = entry;
 138                                 msg.prefix = dest;
 139                                 eigrp_fsm_event(&msg);
 140                         }
 141                         eigrp_IPv4_InternalTLV_free(tlv);
 142                         break;
 143
 144                 case EIGRP_TLV_IPv4_EXT:
 145                 /* DVS: processing of external routes needs packet and fsm work.
 146                  *      for now, lets just not creash the box
 147                  */
 148                 default:
 149                         length = stream_getw(s);
 150                         // -2 for type, -2 for len
 151                         for (length -= 4; length; length--) {
 152                                 (void)stream_getc(s);
 153                         }
 154                 }
 155         }
 156         eigrp_hello_send_ack(nbr);
 157         eigrp_query_send_all(eigrp);
 158         eigrp_update_send_all(eigrp, nbr->ei);
 159 }
 160
 161 void eigrp_send_query(struct eigrp_interface *ei)
 162 {
 163         struct eigrp_packet *ep = NULL;
 164         uint16_t length = EIGRP_HEADER_LEN;
 165         struct listnode *node, *nnode, *node2, *nnode2;
 166         struct eigrp_neighbor *nbr;
 167         struct eigrp_prefix_entry *pe;
 168         bool has_tlv = false;
 169         bool new_packet = true;
 170         uint16_t eigrp_mtu = EIGRP_PACKET_MTU(ei->ifp->mtu);
 171
 172         for (ALL_LIST_ELEMENTS(ei->eigrp->topology_changes_internalIPV4, node,
 173                                nnode, pe)) {
 174                 if (!(pe->req_action & EIGRP_FSM_NEED_QUERY))
 175                         continue;
 176
 177                 if (new_packet) {
 178                         ep = eigrp_packet_new(eigrp_mtu, NULL);
 179
 180                         /* Prepare EIGRP INIT UPDATE header */
 181                         eigrp_packet_header_init(EIGRP_OPC_QUERY, ei->eigrp,
 182                                                  ep->s, 0,
 183                                                  ei->eigrp->sequence_number, 0);
 184
 185                         // encode Authentication TLV, if needed
 186                         if ((ei->params.auth_type == EIGRP_AUTH_TYPE_MD5)
 187                             && (ei->params.auth_keychain != NULL)) {
 188                                 length += eigrp_add_authTLV_MD5_to_stream(ep->s,
 189                                                                           ei);
 190                         }
 191                         new_packet = false;
 192                 }
 193
 194                 length += eigrp_add_internalTLV_to_stream(ep->s, pe);
 195                 has_tlv = true;
 196                 for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr)) {
 197                         if (nbr->state == EIGRP_NEIGHBOR_UP)
 198                                 listnode_add(pe->rij, nbr);
 199                 }
 200
 201                 if (length + EIGRP_TLV_MAX_IPV4_BYTE > eigrp_mtu) {
 202                         if ((ei->params.auth_type == EIGRP_AUTH_TYPE_MD5)
 203                             && ei->params.auth_keychain != NULL) {
 204                                 eigrp_make_md5_digest(ei, ep->s,
 205                                                       EIGRP_AUTH_UPDATE_FLAG);
 206                         }
 207
 208                         eigrp_packet_checksum(ei, ep->s, length);
 209                         ep->length = length;
 210
 211                         ep->dst.s_addr = htonl(EIGRP_MULTICAST_ADDRESS);
 212
 213                         ep->sequence_number = ei->eigrp->sequence_number;
 214                         ei->eigrp->sequence_number++;
 215
 216                         for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr)) {
 217                                 struct eigrp_packet *dup;
 218
 219                                 if (nbr->state != EIGRP_NEIGHBOR_UP)
 220                                         continue;
 221
 222                                 dup = eigrp_packet_duplicate(ep, nbr);
 223                                 /*Put packet to retransmission queue*/
 224                                 eigrp_fifo_push(nbr->retrans_queue, dup);
 225
 226                                 if (nbr->retrans_queue->count == 1)
 227                                         eigrp_send_packet_reliably(nbr);
 228                         }
 229
 230                         has_tlv = false;
 231                         length = 0;
 232                         eigrp_packet_free(ep);
 233                         ep = NULL;
 234                         new_packet = true;
 235                 }
 236         }
 237
 238         if (!has_tlv)
 239                 return;
 240
 241         if ((ei->params.auth_type == EIGRP_AUTH_TYPE_MD5)
 242             && ei->params.auth_keychain != NULL)
 243                 eigrp_make_md5_digest(ei, ep->s, EIGRP_AUTH_UPDATE_FLAG);
 244
 245
 246         /* EIGRP Checksum */
 247         eigrp_packet_checksum(ei, ep->s, length);
 248
 249         ep->length = length;
 250         ep->dst.s_addr = htonl(EIGRP_MULTICAST_ADDRESS);
 251
 252         /*This ack number we await from neighbor*/
 253         ep->sequence_number = ei->eigrp->sequence_number;
 254         ei->eigrp->sequence_number++;
 255
 256         for (ALL_LIST_ELEMENTS(ei->nbrs, node2, nnode2, nbr)) {
 257                 struct eigrp_packet *dup;
 258
 259                 if (nbr->state != EIGRP_NEIGHBOR_UP)
 260                         continue;
 261
 262                 dup = eigrp_packet_duplicate(ep, nbr);
 263                 /*Put packet to retransmission queue*/
 264                 eigrp_fifo_push(nbr->retrans_queue, dup);
 265
 266                 if (nbr->retrans_queue->count == 1)
 267                         eigrp_send_packet_reliably(nbr);
 268         }
 269
 270         eigrp_packet_free(ep);
 271 }