ospf6d/ospf6_bfd.c

   1 /**
   2  * ospf6_bfd.c: IPv6 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 along
  19  * with this program; see the file COPYING; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <zebra.h>
  24
  25 #include "command.h"
  26 #include "linklist.h"
  27 #include "memory.h"
  28 #include "prefix.h"
  29 #include "thread.h"
  30 #include "buffer.h"
  31 #include "stream.h"
  32 #include "zclient.h"
  33 #include "vty.h"
  34 #include "table.h"
  35 #include "bfd.h"
  36 #include "if.h"
  37 #include "ospf6d.h"
  38 #include "ospf6_message.h"
  39 #include "ospf6_neighbor.h"
  40 #include "ospf6_interface.h"
  41 #include "ospf6_route.h"
  42 #include "ospf6_zebra.h"
  43 #include "ospf6_bfd.h"
  44
  45 extern struct zclient *zclient;
  46
  47 /*
  48  * ospf6_bfd_trigger_event - Neighbor is registered/deregistered with BFD when
  49  *                           neighbor state is changed to/from 2way.
  50  */
  51 void ospf6_bfd_trigger_event(struct ospf6_neighbor *on, int old_state,
  52                              int state)
  53 {
  54         int family;
  55         struct in6_addr src, dst;
  56
  57         /* Skip sessions without BFD. */
  58         if (on->bfd_session == NULL)
  59                 return;
  60
  61         if (old_state < OSPF6_NEIGHBOR_TWOWAY
  62             && state >= OSPF6_NEIGHBOR_TWOWAY) {
  63                 /*
  64                  * Check if neighbor address changed.
  65                  *
  66                  * When the neighbor is configured BFD before having an existing
  67                  * connection, then the destination address will be set to `::`
  68                  * which will cause session installation failure. This piece of
  69                  * code updates the address in that case.
  70                  */
  71                 bfd_sess_addresses(on->bfd_session, &family, &src, &dst);
  72                 if (memcmp(&on->linklocal_addr, &dst, sizeof(dst))) {
  73                         bfd_sess_set_ipv6_addrs(on->bfd_session, &src,
  74                                                 &on->linklocal_addr);
  75                 }
  76
  77                 bfd_sess_install(on->bfd_session);
  78         } else if (old_state >= OSPF6_NEIGHBOR_TWOWAY
  79                    && state < OSPF6_NEIGHBOR_TWOWAY)
  80                 bfd_sess_uninstall(on->bfd_session);
  81 }
  82
  83 /*
  84  * ospf6_bfd_reg_dereg_all_nbr - Register/Deregister all neighbors associated
  85  *                               with a interface with BFD through
  86  *                               zebra for starting/stopping the monitoring of
  87  *                               the neighbor rechahability.
  88  */
  89 static void ospf6_bfd_reg_dereg_all_nbr(struct ospf6_interface *oi,
  90                                         bool install)
  91 {
  92         struct ospf6_neighbor *on;
  93         struct listnode *node;
  94
  95         for (ALL_LIST_ELEMENTS_RO(oi->neighbor_list, node, on)) {
  96                 /* Remove all sessions. */
  97                 if (!install) {
  98                         bfd_sess_free(&on->bfd_session);
  99                         continue;
 100                 }
 101
 102                 /* Always allocate session data even if not enabled. */
 103                 ospf6_bfd_info_nbr_create(oi, on);
 104
 105                 /*
 106                  * If not connected yet, don't create any session but defer it
 107                  * for later. See function `ospf6_bfd_trigger_event`.
 108                  */
 109                 if (on->state < OSPF6_NEIGHBOR_TWOWAY)
 110                         continue;
 111
 112                 bfd_sess_install(on->bfd_session);
 113         }
 114 }
 115
 116 static void ospf6_bfd_callback(struct bfd_session_params *bsp,
 117                                const struct bfd_session_status *bss, void *arg)
 118 {
 119         struct ospf6_neighbor *on = arg;
 120
 121         if (bss->state == BFD_STATUS_DOWN
 122             && bss->previous_state == BFD_STATUS_UP) {
 123                 THREAD_OFF(on->inactivity_timer);
 124                 thread_add_event(master, inactivity_timer, on, 0, NULL);
 125         }
 126 }
 127
 128 /*
 129  * ospf6_bfd_info_nbr_create - Create/update BFD information for a neighbor.
 130  */
 131 void ospf6_bfd_info_nbr_create(struct ospf6_interface *oi,
 132                                struct ospf6_neighbor *on)
 133 {
 134         if (!oi->bfd_config.enabled)
 135                 return;
 136
 137         if (on->bfd_session == NULL)
 138                 on->bfd_session = bfd_sess_new(ospf6_bfd_callback, on);
 139
 140         bfd_sess_set_timers(on->bfd_session,
 141                             oi->bfd_config.detection_multiplier,
 142                             oi->bfd_config.min_rx, oi->bfd_config.min_tx);
 143         bfd_sess_set_ipv6_addrs(on->bfd_session, on->ospf6_if->linklocal_addr,
 144                                 &on->linklocal_addr);
 145         bfd_sess_set_interface(on->bfd_session, oi->interface->name);
 146         bfd_sess_set_profile(on->bfd_session, oi->bfd_config.profile);
 147 }
 148
 149 /*
 150  * ospf6_bfd_write_config - Write the interface BFD configuration.
 151  */
 152 void ospf6_bfd_write_config(struct vty *vty, struct ospf6_interface *oi)
 153 {
 154         if (!oi->bfd_config.enabled)
 155                 return;
 156
 157 #if HAVE_BFDD == 0
 158         if (oi->bfd_config.detection_multiplier != BFD_DEF_DETECT_MULT
 159             || oi->bfd_config.min_rx != BFD_DEF_MIN_RX
 160             || oi->bfd_config.min_tx != BFD_DEF_MIN_TX)
 161                 vty_out(vty, " ipv6 ospf6 bfd %d %d %d\n",
 162                         oi->bfd_config.detection_multiplier,
 163                         oi->bfd_config.min_rx, oi->bfd_config.min_tx);
 164         else
 165 #endif /* ! HAVE_BFDD */
 166                 vty_out(vty, " ipv6 ospf6 bfd\n");
 167
 168         if (oi->bfd_config.profile)
 169                 vty_out(vty, " ipv6 ospf6 bfd profile %s\n",
 170                         oi->bfd_config.profile);
 171 }
 172
 173 DEFUN(ipv6_ospf6_bfd, ipv6_ospf6_bfd_cmd,
 174       "ipv6 ospf6 bfd [profile BFDPROF]",
 175       IP6_STR OSPF6_STR
 176       "Enables BFD support\n"
 177       "BFD Profile selection\n"
 178       "BFD Profile name\n")
 179 {
 180         VTY_DECLVAR_CONTEXT(interface, ifp);
 181         struct ospf6_interface *oi;
 182         int prof_idx = 4;
 183         assert(ifp);
 184
 185         oi = (struct ospf6_interface *)ifp->info;
 186         if (oi == NULL)
 187                 oi = ospf6_interface_create(ifp);
 188         assert(oi);
 189
 190         oi->bfd_config.detection_multiplier = BFD_DEF_DETECT_MULT;
 191         oi->bfd_config.min_rx = BFD_DEF_MIN_RX;
 192         oi->bfd_config.min_tx = BFD_DEF_MIN_TX;
 193         oi->bfd_config.enabled = true;
 194         if (argc > prof_idx) {
 195                 XFREE(MTYPE_TMP, oi->bfd_config.profile);
 196                 oi->bfd_config.profile =
 197                         XSTRDUP(MTYPE_TMP, argv[prof_idx]->arg);
 198         }
 199
 200         ospf6_bfd_reg_dereg_all_nbr(oi, true);
 201
 202         return CMD_SUCCESS;
 203 }
 204
 205 DEFUN(no_ipv6_ospf6_bfd_profile, no_ipv6_ospf6_bfd_profile_cmd,
 206       "no ipv6 ospf6 bfd profile [BFDPROF]",
 207       NO_STR IP6_STR OSPF6_STR
 208       "BFD support\n"
 209       "BFD Profile selection\n"
 210       "BFD Profile name\n")
 211 {
 212         VTY_DECLVAR_CONTEXT(interface, ifp);
 213         struct ospf6_interface *oi;
 214         assert(ifp);
 215
 216         oi = (struct ospf6_interface *)ifp->info;
 217         if (oi == NULL)
 218                 oi = ospf6_interface_create(ifp);
 219         assert(oi);
 220
 221         /* BFD not enabled, nothing to do. */
 222         if (!oi->bfd_config.enabled)
 223                 return CMD_SUCCESS;
 224
 225         /* Remove profile and apply new configuration. */
 226         XFREE(MTYPE_TMP, oi->bfd_config.profile);
 227         ospf6_bfd_reg_dereg_all_nbr(oi, true);
 228
 229         return CMD_SUCCESS;
 230 }
 231
 232 #if HAVE_BFDD > 0
 233 DEFUN_HIDDEN(
 234 #else
 235 DEFUN(
 236 #endif /* HAVE_BFDD */
 237        ipv6_ospf6_bfd_param,
 238        ipv6_ospf6_bfd_param_cmd,
 239        "ipv6 ospf6 bfd (2-255) (50-60000) (50-60000)",
 240        IP6_STR
 241        OSPF6_STR
 242        "Enables BFD support\n"
 243        "Detect Multiplier\n"
 244        "Required min receive interval\n"
 245        "Desired min transmit interval\n")
 246 {
 247         VTY_DECLVAR_CONTEXT(interface, ifp);
 248         int idx_number = 3;
 249         int idx_number_2 = 4;
 250         int idx_number_3 = 5;
 251         struct ospf6_interface *oi;
 252
 253         assert(ifp);
 254
 255         oi = (struct ospf6_interface *)ifp->info;
 256         if (oi == NULL)
 257                 oi = ospf6_interface_create(ifp);
 258         assert(oi);
 259
 260         oi->bfd_config.detection_multiplier =
 261                 strtoul(argv[idx_number]->arg, NULL, 10);
 262         oi->bfd_config.min_rx = strtoul(argv[idx_number_2]->arg, NULL, 10);
 263         oi->bfd_config.min_tx = strtoul(argv[idx_number_3]->arg, NULL, 10);
 264         oi->bfd_config.enabled = true;
 265
 266         ospf6_bfd_reg_dereg_all_nbr(oi, true);
 267
 268         return CMD_SUCCESS;
 269 }
 270
 271 DEFUN (no_ipv6_ospf6_bfd,
 272        no_ipv6_ospf6_bfd_cmd,
 273        "no ipv6 ospf6 bfd",
 274        NO_STR
 275        IP6_STR
 276        OSPF6_STR
 277        "Disables BFD support\n"
 278        )
 279 {
 280         VTY_DECLVAR_CONTEXT(interface, ifp);
 281         struct ospf6_interface *oi;
 282         assert(ifp);
 283
 284         oi = (struct ospf6_interface *)ifp->info;
 285         if (oi == NULL)
 286                 oi = ospf6_interface_create(ifp);
 287         assert(oi);
 288
 289         oi->bfd_config.enabled = false;
 290         ospf6_bfd_reg_dereg_all_nbr(oi, false);
 291
 292         return CMD_SUCCESS;
 293 }
 294
 295 void ospf6_bfd_init(void)
 296 {
 297         bfd_protocol_integration_init(zclient, master);
 298
 299         /* Install BFD command */
 300         install_element(INTERFACE_NODE, &ipv6_ospf6_bfd_cmd);
 301         install_element(INTERFACE_NODE, &ipv6_ospf6_bfd_param_cmd);
 302         install_element(INTERFACE_NODE, &no_ipv6_ospf6_bfd_profile_cmd);
 303         install_element(INTERFACE_NODE, &no_ipv6_ospf6_bfd_cmd);
 304 }