pimd/pim_bfd.c

   1 /*
   2  * pim_bfd.c: PIM BFD handling routines
   3  *
   4  * Copyright (C) 2017 Cumulus Networks, Inc.
   5  * Chirag Shah
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; see the file COPYING; if not, write to the
  19  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  20  * MA 02110-1301 USA
  21  */
  22
  23 #include <zebra.h>
  24
  25 #include "lib/json.h"
  26 #include "command.h"
  27 #include "vty.h"
  28 #include "zclient.h"
  29
  30 #include "pim_instance.h"
  31 #include "pim_cmd.h"
  32 #include "pim_vty.h"
  33 #include "pim_iface.h"
  34 #include "pim_bfd.h"
  35 #include "bfd.h"
  36 #include "pimd.h"
  37 #include "pim_zebra.h"
  38
  39 /*
  40  * pim_bfd_write_config - Write the interface BFD configuration.
  41  */
  42 void pim_bfd_write_config(struct vty *vty, struct interface *ifp)
  43 {
  44         struct pim_interface *pim_ifp = ifp->info;
  45         struct bfd_info *bfd_info = NULL;
  46
  47         if (!pim_ifp)
  48                 return;
  49
  50         bfd_info = (struct bfd_info *)pim_ifp->bfd_info;
  51         if (!bfd_info)
  52                 return;
  53
  54 #if HAVE_BFDD == 0
  55         if (CHECK_FLAG(bfd_info->flags, BFD_FLAG_PARAM_CFG))
  56                 vty_out(vty, " ip pim bfd %d %d %d\n", bfd_info->detect_mult,
  57                         bfd_info->required_min_rx, bfd_info->desired_min_tx);
  58         else
  59 #endif /* ! HAVE_BFDD */
  60                 vty_out(vty, " ip pim bfd\n");
  61 }
  62
  63 /*
  64  * pim_bfd_show_info - Show BFD info structure
  65  */
  66 void pim_bfd_show_info(struct vty *vty, void *bfd_info, json_object *json_obj,
  67                        bool use_json, int param_only)
  68 {
  69         if (param_only)
  70                 bfd_show_param(vty, (struct bfd_info *)bfd_info, 1, 0, use_json,
  71                                json_obj);
  72         else
  73                 bfd_show_info(vty, (struct bfd_info *)bfd_info, 0, 1, use_json,
  74                               json_obj);
  75 }
  76
  77 /*
  78  * pim_bfd_info_nbr_create - Create/update BFD information for a neighbor.
  79  */
  80 void pim_bfd_info_nbr_create(struct pim_interface *pim_ifp,
  81                              struct pim_neighbor *neigh)
  82 {
  83         struct bfd_info *nbr_bfd_info = NULL;
  84
  85         /* Check if Pim Interface BFD is enabled */
  86         if (!pim_ifp || !pim_ifp->bfd_info)
  87                 return;
  88
  89         if (!neigh->bfd_info)
  90                 neigh->bfd_info = bfd_info_create();
  91
  92         if (!neigh->bfd_info)
  93                 return;
  94
  95         nbr_bfd_info = (struct bfd_info *)neigh->bfd_info;
  96         nbr_bfd_info->detect_mult = pim_ifp->bfd_info->detect_mult;
  97         nbr_bfd_info->desired_min_tx = pim_ifp->bfd_info->desired_min_tx;
  98         nbr_bfd_info->required_min_rx = pim_ifp->bfd_info->required_min_rx;
  99 }
 100
 101 /*
 102  * pim_bfd_info_free - Free BFD info structure
 103  */
 104 void pim_bfd_info_free(struct bfd_info **bfd_info)
 105 {
 106         bfd_info_free(bfd_info);
 107 }
 108
 109 static void pim_bfd_reg_dereg_nbr(struct pim_neighbor *nbr, int command)
 110 {
 111         struct pim_interface *pim_ifp = NULL;
 112         struct bfd_info *bfd_info = NULL;
 113         struct zclient *zclient = NULL;
 114
 115         zclient = pim_zebra_zclient_get();
 116
 117         if (!nbr)
 118                 return;
 119         pim_ifp = nbr->interface->info;
 120         bfd_info = (struct bfd_info *)pim_ifp->bfd_info;
 121         if (!bfd_info)
 122                 return;
 123         if (PIM_DEBUG_PIM_TRACE) {
 124                 char str[INET_ADDRSTRLEN];
 125                 pim_inet4_dump("<bfd_nbr?>", nbr->source_addr, str,
 126                                sizeof(str));
 127                 zlog_debug("%s Nbr %s %s with BFD", __PRETTY_FUNCTION__, str,
 128                            bfd_get_command_dbg_str(command));
 129         }
 130         bfd_peer_sendmsg(zclient, bfd_info, AF_INET, &nbr->source_addr, NULL,
 131                          nbr->interface->name, 0, 0, command, 0, VRF_DEFAULT);
 132 }
 133
 134 /*
 135  * pim_bfd_reg_dereg_all_nbr - Register/Deregister all neighbors associated
 136  *                              with a interface with BFD through
 137  *                              zebra for starting/stopping the monitoring of
 138  *                              the neighbor rechahability.
 139  */
 140 int pim_bfd_reg_dereg_all_nbr(struct interface *ifp, int command)
 141 {
 142         struct pim_interface *pim_ifp = NULL;
 143         struct listnode *node = NULL;
 144         struct pim_neighbor *neigh = NULL;
 145
 146         pim_ifp = ifp->info;
 147         if (!pim_ifp)
 148                 return -1;
 149         if (!pim_ifp->bfd_info)
 150                 return -1;
 151
 152         for (ALL_LIST_ELEMENTS_RO(pim_ifp->pim_neighbor_list, node, neigh)) {
 153                 if (command != ZEBRA_BFD_DEST_DEREGISTER)
 154                         pim_bfd_info_nbr_create(pim_ifp, neigh);
 155                 else
 156                         pim_bfd_info_free((struct bfd_info **)&neigh->bfd_info);
 157
 158                 pim_bfd_reg_dereg_nbr(neigh, command);
 159         }
 160
 161         return 0;
 162 }
 163
 164 /*
 165  * pim_bfd_trigger_event - Neighbor is registered/deregistered with BFD when
 166  *                          neighbor state is changed to/from 2way.
 167  */
 168 void pim_bfd_trigger_event(struct pim_interface *pim_ifp,
 169                            struct pim_neighbor *nbr, uint8_t nbr_up)
 170 {
 171         if (nbr_up) {
 172                 pim_bfd_info_nbr_create(pim_ifp, nbr);
 173                 pim_bfd_reg_dereg_nbr(nbr, ZEBRA_BFD_DEST_REGISTER);
 174         } else {
 175                 pim_bfd_info_free(&nbr->bfd_info);
 176                 pim_bfd_reg_dereg_nbr(nbr, ZEBRA_BFD_DEST_DEREGISTER);
 177         }
 178 }
 179
 180 /*
 181  * pim_bfd_if_param_set - Set the configured BFD paramter values for
 182  *                         interface.
 183  */
 184 void pim_bfd_if_param_set(struct interface *ifp, uint32_t min_rx,
 185                           uint32_t min_tx, uint8_t detect_mult, int defaults)
 186 {
 187         struct pim_interface *pim_ifp = ifp->info;
 188         int command = 0;
 189
 190         if (!pim_ifp)
 191                 return;
 192         bfd_set_param((struct bfd_info **)&(pim_ifp->bfd_info), min_rx, min_tx,
 193                       detect_mult, defaults, &command);
 194
 195         if (pim_ifp->bfd_info) {
 196                 if (PIM_DEBUG_PIM_TRACE)
 197                         zlog_debug("%s: interface %s has bfd_info",
 198                                    __PRETTY_FUNCTION__, ifp->name);
 199         }
 200         if (command)
 201                 pim_bfd_reg_dereg_all_nbr(ifp, command);
 202 }
 203
 204
 205 /*
 206  * pim_bfd_interface_dest_update - Find the neighbor for which the BFD status
 207  *                                  has changed and bring down the neighbor
 208  *                                  connectivity if the BFD status changed to
 209  *                                  down.
 210  */
 211 static int pim_bfd_interface_dest_update(int command, struct zclient *zclient,
 212                                          zebra_size_t length, vrf_id_t vrf_id)
 213 {
 214         struct interface *ifp = NULL;
 215         struct pim_interface *pim_ifp = NULL;
 216         struct prefix p;
 217         int status;
 218         char msg[100];
 219         int old_status;
 220         struct bfd_info *bfd_info = NULL;
 221         struct timeval tv;
 222         struct listnode *neigh_node = NULL;
 223         struct listnode *neigh_nextnode = NULL;
 224         struct pim_neighbor *neigh = NULL;
 225
 226         ifp = bfd_get_peer_info(zclient->ibuf, &p, NULL, &status, vrf_id);
 227
 228         if ((ifp == NULL) || (p.family != AF_INET))
 229                 return 0;
 230
 231         pim_ifp = ifp->info;
 232         if (!pim_ifp)
 233                 return 0;
 234
 235         if (!pim_ifp->bfd_info) {
 236                 if (PIM_DEBUG_PIM_TRACE)
 237                         zlog_debug("%s: pim interface %s BFD is disabled ",
 238                                    __PRETTY_FUNCTION__, ifp->name);
 239                 return 0;
 240         }
 241
 242         if (PIM_DEBUG_PIM_TRACE) {
 243                 char buf[PREFIX2STR_BUFFER];
 244                 prefix2str(&p, buf, sizeof(buf));
 245                 zlog_debug("%s: interface %s bfd destination %s %s",
 246                            __PRETTY_FUNCTION__, ifp->name, buf,
 247                            bfd_get_status_str(status));
 248         }
 249
 250         for (ALL_LIST_ELEMENTS(pim_ifp->pim_neighbor_list, neigh_node,
 251                                neigh_nextnode, neigh)) {
 252                 /* Check neigh address matches with BFD address */
 253                 if (neigh->source_addr.s_addr != p.u.prefix4.s_addr)
 254                         continue;
 255
 256                 bfd_info = (struct bfd_info *)neigh->bfd_info;
 257                 if (bfd_info->status == status) {
 258                         if (PIM_DEBUG_PIM_TRACE) {
 259                                 char str[INET_ADDRSTRLEN];
 260                                 pim_inet4_dump("<nht_nbr?>", neigh->source_addr,
 261                                                str, sizeof(str));
 262                                 zlog_debug("%s: bfd status is same for nbr %s",
 263                                            __PRETTY_FUNCTION__, str);
 264                         }
 265                         continue;
 266                 }
 267                 old_status = bfd_info->status;
 268                 bfd_info->status = status;
 269                 monotime(&tv);
 270                 bfd_info->last_update = tv.tv_sec;
 271
 272                 if (PIM_DEBUG_PIM_TRACE) {
 273                         zlog_debug("%s: status %s old_status %s",
 274                                    __PRETTY_FUNCTION__,
 275                                    bfd_get_status_str(status),
 276                                    bfd_get_status_str(old_status));
 277                 }
 278                 if ((status == BFD_STATUS_DOWN)
 279                     && (old_status == BFD_STATUS_UP)) {
 280                         snprintf(msg, sizeof(msg), "BFD Session Expired");
 281                         pim_neighbor_delete(ifp, neigh, msg);
 282                 }
 283         }
 284         return 0;
 285 }
 286
 287 /*
 288  * pim_bfd_nbr_replay - Replay all the neighbors that have BFD enabled
 289  *                       to zebra
 290  */
 291 static int pim_bfd_nbr_replay(int command, struct zclient *zclient,
 292                               zebra_size_t length, vrf_id_t vrf_id)
 293 {
 294         struct interface *ifp = NULL;
 295         struct pim_interface *pim_ifp = NULL;
 296         struct pim_neighbor *neigh = NULL;
 297         struct listnode *neigh_node;
 298         struct listnode *neigh_nextnode;
 299         struct vrf *vrf = NULL;
 300
 301         /* Send the client registration */
 302         bfd_client_sendmsg(zclient, ZEBRA_BFD_CLIENT_REGISTER);
 303
 304         RB_FOREACH (vrf, vrf_name_head, &vrfs_by_name) {
 305                 FOR_ALL_INTERFACES (vrf, ifp) {
 306                         pim_ifp = ifp->info;
 307
 308                         if (!pim_ifp)
 309                                 continue;
 310
 311                         if (pim_ifp->pim_sock_fd < 0)
 312                                 continue;
 313
 314                         for (ALL_LIST_ELEMENTS(pim_ifp->pim_neighbor_list,
 315                                                neigh_node, neigh_nextnode,
 316                                                neigh)) {
 317                                 if (!neigh->bfd_info)
 318                                         continue;
 319                                 if (PIM_DEBUG_PIM_TRACE) {
 320                                         char str[INET_ADDRSTRLEN];
 321
 322                                         pim_inet4_dump("<bfd_nbr?>",
 323                                                        neigh->source_addr, str,
 324                                                        sizeof(str));
 325                                         zlog_debug(
 326                                                 "%s: Replaying Pim Neigh %s to BFD vrf_id %u",
 327                                                 __PRETTY_FUNCTION__, str,
 328                                                 vrf->vrf_id);
 329                                 }
 330                                 pim_bfd_reg_dereg_nbr(neigh,
 331                                                       ZEBRA_BFD_DEST_UPDATE);
 332                         }
 333                 }
 334         }
 335         return 0;
 336 }
 337
 338 void pim_bfd_init(void)
 339 {
 340         struct zclient *zclient = NULL;
 341
 342         zclient = pim_zebra_zclient_get();
 343
 344         bfd_gbl_init();
 345
 346         zclient->interface_bfd_dest_update = pim_bfd_interface_dest_update;
 347         zclient->bfd_dest_replay = pim_bfd_nbr_replay;
 348 }