ospfd/ospf_bfd.c

   1 /**
   2  * ospf_bfd.c: OSPF BFD handling routines
   3  *
   4  * @copyright Copyright (C) 2015 Cumulus Networks, Inc.
   5  *
   6  * This file is part of GNU Zebra.
   7  *
   8  * GNU Zebra is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * GNU Zebra is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  20  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  21  * 02111-1307, USA.
  22  */
  23
  24 #include <zebra.h>
  25
  26 #include "command.h"
  27 #include "linklist.h"
  28 #include "memory.h"
  29 #include "prefix.h"
  30 #include "thread.h"
  31 #include "buffer.h"
  32 #include "stream.h"
  33 #include "zclient.h"
  34 #include "vty.h"
  35 #include "table.h"
  36 #include "bfd.h"
  37 #include "ospfd.h"
  38 #include "ospf_asbr.h"
  39 #include "ospf_lsa.h"
  40 #include "ospf_lsdb.h"
  41 #include "ospf_neighbor.h"
  42 #include "ospf_interface.h"
  43 #include "ospf_nsm.h"
  44 #include "ospf_bfd.h"
  45 #include "ospf_dump.h"
  46 #include "ospf_vty.h"
  47
  48 extern struct zclient *zclient;
  49
  50 /*
  51  * ospf_bfd_reg_dereg_nbr - Register/Deregister a neighbor with BFD through
  52  *                          zebra for starting/stopping the monitoring of
  53  *                          the neighbor rechahability.
  54  */
  55 static void
  56 ospf_bfd_reg_dereg_nbr (struct ospf_neighbor *nbr, int command)
  57 {
  58   struct ospf_interface *oi = nbr->oi;
  59   struct interface *ifp = oi->ifp;
  60   struct ospf_if_params *params;
  61   struct bfd_info *bfd_info;
  62
  63   /* Check if BFD is enabled */
  64   params = IF_DEF_PARAMS (ifp);
  65
  66   /* Check if BFD is enabled */
  67   if (!params->bfd_info)
  68     return;
  69   bfd_info = (struct bfd_info *)params->bfd_info;
  70
  71   if (IS_DEBUG_OSPF(zebra, ZEBRA_INTERFACE))
  72     zlog_debug ("%s nbr (%s) with BFD",
  73                   bfd_get_command_dbg_str(command),
  74                   inet_ntoa (nbr->src));
  75
  76   bfd_peer_sendmsg (zclient, bfd_info, AF_INET,
  77                     &nbr->src, NULL, ifp->name, 0, 0, command, 0);
  78 }
  79
  80 /*
  81  * ospf_bfd_trigger_event - Neighbor is registered/deregistered with BFD when
  82  *                          neighbor state is changed to/from 2way.
  83  */
  84 void
  85 ospf_bfd_trigger_event(struct ospf_neighbor *nbr, int old_state, int state)
  86 {
  87   if ((old_state < NSM_TwoWay) && (state >= NSM_TwoWay))
  88     ospf_bfd_reg_dereg_nbr(nbr, ZEBRA_BFD_DEST_REGISTER);
  89   else if ((old_state >= NSM_TwoWay) && (state < NSM_TwoWay))
  90     ospf_bfd_reg_dereg_nbr(nbr, ZEBRA_BFD_DEST_DEREGISTER);
  91 }
  92
  93 /*
  94  * ospf_bfd_reg_dereg_all_nbr - Register/Deregister all neighbors associated
  95  *                              with a interface with BFD through
  96  *                              zebra for starting/stopping the monitoring of
  97  *                              the neighbor rechahability.
  98  */
  99 static int
 100 ospf_bfd_reg_dereg_all_nbr (struct interface *ifp, int command)
 101 {
 102   struct ospf_interface *oi;
 103   struct route_table *nbrs;
 104   struct ospf_neighbor *nbr;
 105   struct route_node *irn;
 106   struct route_node *nrn;
 107
 108   for (irn = route_top (IF_OIFS (ifp)); irn; irn = route_next (irn))
 109     {
 110       if ((oi = irn->info) == NULL)
 111         continue;
 112
 113       if ((nbrs = oi->nbrs) == NULL)
 114         continue;
 115
 116       for (nrn = route_top (nbrs); nrn; nrn = route_next (nrn))
 117         {
 118           if ((nbr = nrn->info) == NULL || nbr == oi->nbr_self)
 119             continue;
 120
 121           if (nbr->state < NSM_TwoWay)
 122             continue;
 123
 124           ospf_bfd_reg_dereg_nbr(nbr, command);
 125         }
 126     }
 127
 128   return 0;
 129 }
 130
 131 /*
 132  * ospf_bfd_nbr_replay - Replay all the neighbors that have BFD enabled
 133  *                       to zebra
 134  */
 135 static int
 136 ospf_bfd_nbr_replay (int command, struct zclient *client, zebra_size_t length)
 137 {
 138   struct listnode *inode, *node, *onode;
 139   struct ospf *ospf;
 140   struct ospf_interface *oi;
 141   struct route_table *nbrs;
 142   struct route_node *rn;
 143   struct ospf_neighbor *nbr;
 144   struct ospf_if_params *params;
 145
 146   if (IS_DEBUG_OSPF(zebra, ZEBRA_INTERFACE))
 147     {
 148       zlog_debug("Zebra: BFD Dest replay request");
 149     }
 150
 151   /* Replay the neighbor, if BFD is enabled in BGP */
 152   for (ALL_LIST_ELEMENTS (om->ospf, node, onode, ospf))
 153     {
 154       for (ALL_LIST_ELEMENTS_RO (ospf->oiflist, inode, oi))
 155         {
 156           if ((nbrs = oi->nbrs) == NULL)
 157             continue;
 158
 159           params = IF_DEF_PARAMS (oi->ifp);
 160           if (!params->bfd_info)
 161             continue;
 162
 163           for (rn = route_top (nbrs); rn; rn = route_next (rn))
 164             {
 165               if ((nbr = rn->info) == NULL || nbr == oi->nbr_self)
 166                 continue;
 167
 168               if (nbr->state < NSM_TwoWay)
 169                 continue;
 170
 171               if (IS_DEBUG_OSPF(zebra, ZEBRA_INTERFACE))
 172                 zlog_debug ("Replaying nbr (%s) to BFD", inet_ntoa (nbr->src));
 173
 174               ospf_bfd_reg_dereg_nbr(nbr, ZEBRA_BFD_DEST_UPDATE);
 175             }
 176         }
 177     }
 178   return 0;
 179 }
 180
 181 /*
 182  * ospf_bfd_interface_dest_down - Find the neighbor for which the BFD status
 183  *                                has changed and bring down the neighbor
 184  *                                connectivity.
 185  */
 186 static int
 187 ospf_bfd_interface_dest_down (int command, struct zclient *zclient,
 188                               zebra_size_t length)
 189 {
 190   struct interface *ifp;
 191   struct ospf_interface *oi;
 192   struct ospf_if_params *params;
 193   struct ospf_neighbor *nbr;
 194   struct route_node *node;
 195   struct prefix p;
 196
 197   ifp = bfd_get_peer_info (zclient->ibuf, &p, NULL);
 198
 199   if ((ifp == NULL) || (p.family != AF_INET))
 200     return 0;
 201
 202   if (IS_DEBUG_OSPF (zebra, ZEBRA_INTERFACE))
 203     {
 204       char buf[128];
 205       prefix2str(&p, buf, sizeof(buf));
 206       zlog_debug("Zebra: interface %s bfd destination %s down", ifp->name, buf);
 207     }
 208
 209   params = IF_DEF_PARAMS (ifp);
 210   if (!params->bfd_info)
 211     return 0;
 212
 213   for (node = route_top (IF_OIFS (ifp)); node; node = route_next (node))
 214     {
 215       if ((oi = node->info) == NULL)
 216         continue;
 217
 218       nbr = ospf_nbr_lookup_by_addr (oi->nbrs, &p.u.prefix4);
 219       if (!nbr)
 220         continue;
 221
 222       if (IS_DEBUG_OSPF (nsm, NSM_EVENTS))
 223         zlog_debug ("NSM[%s:%s]: BFD Down",
 224                     IF_NAME (nbr->oi), inet_ntoa (nbr->address.u.prefix4));
 225
 226       OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_InactivityTimer);
 227     }
 228
 229   return 0;
 230 }
 231
 232 /*
 233  * ospf_bfd_write_config - Write the interface BFD configuration.
 234  */
 235 void
 236 ospf_bfd_write_config(struct vty *vty, struct ospf_if_params *params)
 237
 238 {
 239   struct bfd_info *bfd_info;
 240
 241   if (!params->bfd_info)
 242     return;
 243
 244   bfd_info = (struct bfd_info *)params->bfd_info;
 245
 246   if (CHECK_FLAG(bfd_info->flags, BFD_FLAG_PARAM_CFG))
 247     vty_out (vty, " ip ospf bfd %d %d %d%s",
 248               bfd_info->detect_mult, bfd_info->required_min_rx,
 249               bfd_info->desired_min_tx, VTY_NEWLINE);
 250   else
 251     vty_out (vty, " ip ospf bfd%s", VTY_NEWLINE);
 252 }
 253
 254
 255 /*
 256  * ospf_bfd_if_param_set - Set the configured BFD paramter values for
 257  *                         interface.
 258  */
 259 static void
 260 ospf_bfd_if_param_set (struct interface *ifp, u_int32_t min_rx,
 261                        u_int32_t min_tx, u_int8_t detect_mult, int defaults)
 262 {
 263   struct ospf_if_params *params;
 264   int command = 0;
 265
 266   params = IF_DEF_PARAMS (ifp);
 267
 268   bfd_set_param(&(params->bfd_info), min_rx, min_tx, detect_mult,
 269                 defaults, &command);
 270   if (command)
 271     ospf_bfd_reg_dereg_all_nbr(ifp, command);
 272 }
 273
 274
 275 DEFUN (ip_ospf_bfd,
 276        ip_ospf_bfd_cmd,
 277        "ip ospf bfd",
 278        "IP Information\n"
 279        "OSPF interface commands\n"
 280        "Enables BFD support\n")
 281 {
 282   struct interface *ifp = (struct interface *) vty->index;
 283
 284   assert (ifp);
 285   ospf_bfd_if_param_set (ifp, BFD_DEF_MIN_RX, BFD_DEF_MIN_TX,
 286                          BFD_DEF_DETECT_MULT, 1);
 287
 288   return CMD_SUCCESS;
 289 }
 290
 291 DEFUN (ip_ospf_bfd_param,
 292        ip_ospf_bfd_param_cmd,
 293        "ip ospf bfd " BFD_CMD_DETECT_MULT_RANGE BFD_CMD_MIN_RX_RANGE BFD_CMD_MIN_TX_RANGE,
 294        "IP Information\n"
 295        "OSPF interface commands\n"
 296        "Enables BFD support\n"
 297        "Detect Multiplier\n"
 298        "Required min receive interval\n"
 299        "Desired min transmit interval\n")
 300 {
 301   struct interface *ifp = (struct interface *) vty->index;
 302   u_int32_t rx_val;
 303   u_int32_t tx_val;
 304   u_int8_t dm_val;
 305   int ret;
 306
 307   assert (ifp);
 308
 309   if ((ret = bfd_validate_param (vty, argv[0], argv[1], argv[2], &dm_val,
 310                                  &rx_val, &tx_val)) != CMD_SUCCESS)
 311     return ret;
 312
 313   ospf_bfd_if_param_set (ifp, rx_val, tx_val, dm_val, 0);
 314
 315   return CMD_SUCCESS;
 316 }
 317
 318 DEFUN (no_ip_ospf_bfd,
 319        no_ip_ospf_bfd_cmd,
 320        "no ip ospf bfd",
 321        NO_STR
 322        "IP Information\n"
 323        "OSPF interface commands\n"
 324        "Disables BFD support\n")
 325 {
 326   struct interface *ifp = (struct interface *)vty->index;
 327   struct ospf_if_params *params;
 328
 329   assert (ifp);
 330
 331   params = IF_DEF_PARAMS (ifp);
 332   if (params->bfd_info)
 333     {
 334       ospf_bfd_reg_dereg_all_nbr(ifp, ZEBRA_BFD_DEST_DEREGISTER);
 335       bfd_info_free(&(params->bfd_info));
 336     }
 337
 338   return CMD_SUCCESS;
 339 }
 340
 341 void
 342 ospf_bfd_init(void)
 343 {
 344   /* Initialize BFD client functions */
 345   zclient->interface_bfd_dest_down = ospf_bfd_interface_dest_down;
 346   zclient->bfd_dest_replay = ospf_bfd_nbr_replay;
 347
 348   /* Install BFD command */
 349   install_element (INTERFACE_NODE, &ip_ospf_bfd_cmd);
 350   install_element (INTERFACE_NODE, &ip_ospf_bfd_param_cmd);
 351   install_element (INTERFACE_NODE, &no_ip_ospf_bfd_cmd);
 352 }