lib/bfd.h

   1 /**
   2  * bfd.h: BFD definitions and structures
   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 #ifndef _ZEBRA_BFD_H
  24 #define _ZEBRA_BFD_H
  25
  26 #include "lib/json.h"
  27 #include "lib/zclient.h"
  28
  29 #ifdef __cplusplus
  30 extern "C" {
  31 #endif
  32
  33 #define BFD_DEF_MIN_RX 300
  34 #define BFD_MIN_MIN_RX 50
  35 #define BFD_MAX_MIN_RX 60000
  36 #define BFD_DEF_MIN_TX 300
  37 #define BFD_MIN_MIN_TX 50
  38 #define BFD_MAX_MIN_TX 60000
  39 #define BFD_DEF_DETECT_MULT 3
  40 #define BFD_MIN_DETECT_MULT 2
  41 #define BFD_MAX_DETECT_MULT 255
  42
  43 #define BFD_STATUS_UNKNOWN    (1 << 0) /* BFD session status never received */
  44 #define BFD_STATUS_DOWN       (1 << 1) /* BFD session status is down */
  45 #define BFD_STATUS_UP         (1 << 2) /* BFD session status is up */
  46 #define BFD_STATUS_ADMIN_DOWN (1 << 3) /* BFD session is admin down */
  47
  48 #define BFD_PROFILE_NAME_LEN 64
  49
  50 const char *bfd_get_status_str(int status);
  51
  52 extern void bfd_client_sendmsg(struct zclient *zclient, int command,
  53                                vrf_id_t vrf_id);
  54
  55 /*
  56  * BFD new API.
  57  */
  58
  59 /* Forward declaration of argument struct. */
  60 struct bfd_session_params;
  61
  62 /** Session state definitions. */
  63 enum bfd_session_state {
  64         /** Session state is unknown or not initialized. */
  65         BSS_UNKNOWN = BFD_STATUS_UNKNOWN,
  66         /** Local or remote peer administratively shutdown the session. */
  67         BSS_ADMIN_DOWN = BFD_STATUS_ADMIN_DOWN,
  68         /** Session is down. */
  69         BSS_DOWN = BFD_STATUS_DOWN,
  70         /** Session is up and working correctly. */
  71         BSS_UP = BFD_STATUS_UP,
  72 };
  73
  74 /** BFD session status information */
  75 struct bfd_session_status {
  76         /** Current session state. */
  77         enum bfd_session_state state;
  78         /** Previous session state. */
  79         enum bfd_session_state previous_state;
  80         /** Remote Control Plane Independent bit state. */
  81         bool remote_cbit;
  82         /** Last event occurrence. */
  83         time_t last_event;
  84 };
  85
  86 /**
  87  * Session status update callback.
  88  *
  89  * \param bsp BFD session parameters.
  90  * \param bss BFD session status.
  91  * \param arg application independent data.
  92  */
  93 typedef void (*bsp_status_update)(struct bfd_session_params *bsp,
  94                                   const struct bfd_session_status *bss,
  95                                   void *arg);
  96
  97 /**
  98  * Allocates and initializes the session parameters.
  99  *
 100  * \param updatecb status update notification callback.
 101  * \param args application independent data.
 102  *
 103  * \returns pointer to configuration storage.
 104  */
 105 struct bfd_session_params *bfd_sess_new(bsp_status_update updatecb, void *args);
 106
 107 /**
 108  * Uninstall session if installed and free resources allocated by the
 109  * parameters. Already sets pointer to `NULL` to avoid dangling references.
 110  *
 111  * \param bsp session parameters.
 112  */
 113 void bfd_sess_free(struct bfd_session_params **bsp);
 114
 115 /**
 116  * Set the local and peer address of the BFD session.
 117  *
 118  * NOTE:
 119  * If the address changed the session is removed and must be installed again
 120  * with `bfd_sess_install`.
 121  *
 122  * \param bsp BFD session parameters.
 123  * \param src local address (optional, can be `NULL`).
 124  * \param dst remote address (mandatory).
 125  */
 126 void bfd_sess_set_ipv4_addrs(struct bfd_session_params *bsp,
 127                              const struct in_addr *src,
 128                              const struct in_addr *dst);
 129
 130 /**
 131  * Set the local and peer address of the BFD session.
 132  *
 133  * NOTE:
 134  * If the address changed the session is removed and must be installed again
 135  * with `bfd_sess_install`.
 136  *
 137  * \param bsp BFD session parameters.
 138  * \param src local address (optional, can be `NULL`).
 139  * \param dst remote address (mandatory).
 140  */
 141 void bfd_sess_set_ipv6_addrs(struct bfd_session_params *bsp,
 142                              const struct in6_addr *src,
 143                              const struct in6_addr *dst);
 144
 145 /**
 146  * Configure the BFD session interface.
 147  *
 148  * NOTE:
 149  * If the interface changed the session is removed and must be installed again
 150  * with `bfd_sess_install`.
 151  *
 152  * \param bsp BFD session parameters.
 153  * \param ifname interface name (or `NULL` to remove it).
 154  */
 155 void bfd_sess_set_interface(struct bfd_session_params *bsp, const char *ifname);
 156
 157 /**
 158  * Configure the BFD session profile name.
 159  *
 160  * NOTE:
 161  * Session profile will only change after a `bfd_sess_install`.
 162  *
 163  * \param bsp BFD session parameters.
 164  * \param profile profile name (or `NULL` to remove it).
 165  */
 166 void bfd_sess_set_profile(struct bfd_session_params *bsp, const char *profile);
 167
 168 /**
 169  * Configure the BFD session VRF.
 170  *
 171  * NOTE:
 172  * If the VRF changed the session is removed and must be installed again
 173  * with `bfd_sess_install`.
 174  *
 175  * \param bsp BFD session parameters.
 176  * \param vrf_id the VRF identification number.
 177  */
 178 void bfd_sess_set_vrf(struct bfd_session_params *bsp, vrf_id_t vrf_id);
 179
 180 /**
 181  * Configure the BFD session single/multi hop setting.
 182  *
 183  * NOTE:
 184  * If the number of hops is changed the session is removed and must be
 185  * installed again with `bfd_sess_install`.
 186  *
 187  * \param bsp BFD session parameters.
 188  * \param hops maximum amount of hops expected (1 for single hop, 2 or
 189  *             more for multi hop).
 190  */
 191 void bfd_sess_set_hop_count(struct bfd_session_params *bsp, uint8_t hops);
 192
 193 /**
 194  * Configure the BFD session to set the Control Plane Independent bit.
 195  *
 196  * NOTE:
 197  * Session CPI bit will only change after a `bfd_sess_install`.
 198  *
 199  * \param bsp BFD session parameters.
 200  * \param enable BFD Control Plane Independent state.
 201  */
 202 void bfd_sess_set_cbit(struct bfd_session_params *bsp, bool enable);
 203
 204 /**
 205  * DEPRECATED: please avoid using timers directly and use profiles instead.
 206  *
 207  * Configures the BFD session timers to use. This is specially useful with
 208  * `ptm-bfd` which does not support timers.
 209  *
 210  * NOTE:
 211  * Session timers will only apply if the session has not been created yet.
 212  * If the session is already installed you must uninstall and install again
 213  * to take effect.
 214  *
 215  * \param bsp BFD session parameters.
 216  * \param detection_multiplier the detection multiplier value.
 217  * \param min_rx minimum required receive period.
 218  * \param min_tx minimum required transmission period.
 219  */
 220 void bfd_sess_set_timers(struct bfd_session_params *bsp,
 221                          uint8_t detection_multiplier, uint32_t min_rx,
 222                          uint32_t min_tx);
 223
 224 /**
 225  * Configures the automatic source selection for the BFD session.
 226  *
 227  * NOTE:
 228  * Setting this configuration will override the IP source value set by
 229  * `bfd_sess_set_ipv4_addrs` or `bfd_sess_set_ipv6_addrs`.
 230  *
 231  * \param bsp BFD session parameters
 232  * \param enable BFD automatic source selection state.
 233  */
 234 void bfd_sess_set_auto_source(struct bfd_session_params *bsp, bool enable);
 235
 236 /**
 237  * Installs or updates the BFD session based on the saved session arguments.
 238  *
 239  * NOTE:
 240  * This function has a delayed effect: it will only install/update after
 241  * all northbound/CLI command batch finishes.
 242  *
 243  * \param bsp session parameters.
 244  */
 245 void bfd_sess_install(struct bfd_session_params *bsp);
 246
 247 /**
 248  * Uninstall the BFD session based on the saved session arguments.
 249  *
 250  * NOTE:
 251  * This function uninstalls the session immediately (if installed) and cancels
 252  * any previous `bfd_sess_install` calls.
 253  *
 254  * \param bsp session parameters.
 255  */
 256 void bfd_sess_uninstall(struct bfd_session_params *bsp);
 257
 258 /**
 259  * Get BFD session current status.
 260  *
 261  * \param bsp session parameters.
 262  *
 263  * \returns BFD session status data structure.
 264  */
 265 enum bfd_session_state bfd_sess_status(const struct bfd_session_params *bsp);
 266
 267 /**
 268  * Get BFD session amount of hops configured value.
 269  *
 270  * \param bsp session parameters.
 271  *
 272  * \returns configured amount of hops.
 273  */
 274 uint8_t bfd_sess_hop_count(const struct bfd_session_params *bsp);
 275
 276 /**
 277  * Get BFD session profile configured value.
 278  *
 279  * \param bsp session parameters.
 280  *
 281  * \returns configured profile name (or `NULL` if empty).
 282  */
 283 const char *bfd_sess_profile(const struct bfd_session_params *bsp);
 284
 285 /**
 286  * Get BFD session addresses.
 287  *
 288  * \param bsp session parameters.
 289  * \param family the address family being used (AF_INET or AF_INET6).
 290  * \param src source address (optional, may be `NULL`).
 291  * \param dst peer address (optional, may be `NULL`).
 292  */
 293 void bfd_sess_addresses(const struct bfd_session_params *bsp, int *family,
 294                         struct in6_addr *src, struct in6_addr *dst);
 295 /**
 296  * Get BFD session interface name.
 297  *
 298  * \param bsp session parameters.
 299  *
 300  * \returns `NULL` if not set otherwise the interface name.
 301  */
 302 const char *bfd_sess_interface(const struct bfd_session_params *bsp);
 303
 304 /**
 305  * Get BFD session VRF name.
 306  *
 307  * \param bsp session parameters.
 308  *
 309  * \returns the VRF name.
 310  */
 311 const char *bfd_sess_vrf(const struct bfd_session_params *bsp);
 312
 313 /**
 314  * Get BFD session VRF ID.
 315  *
 316  * \param bsp session parameters.
 317  *
 318  * \returns the VRF name.
 319  */
 320 vrf_id_t bfd_sess_vrf_id(const struct bfd_session_params *bsp);
 321
 322 /**
 323  * Get BFD session control plane independent bit configuration state.
 324  *
 325  * \param bsp session parameters.
 326  *
 327  * \returns `true` if enabled otherwise `false`.
 328  */
 329 bool bfd_sess_cbit(const struct bfd_session_params *bsp);
 330
 331 /**
 332  * DEPRECATED: please avoid using timers directly and use profiles instead.
 333  *
 334  * Gets the configured timers.
 335  *
 336  * \param bsp BFD session parameters.
 337  * \param detection_multiplier the detection multiplier value.
 338  * \param min_rx minimum required receive period.
 339  * \param min_tx minimum required transmission period.
 340  */
 341 void bfd_sess_timers(const struct bfd_session_params *bsp,
 342                      uint8_t *detection_multiplier, uint32_t *min_rx,
 343                      uint32_t *min_tx);
 344
 345 /**
 346  * Gets the automatic source selection state.
 347  */
 348 bool bfd_sess_auto_source(const struct bfd_session_params *bsp);
 349
 350 /**
 351  * Show BFD session configuration and status. If `json` is provided (e.g. not
 352  * `NULL`) then information will be inserted in object, otherwise printed to
 353  * `vty`.
 354  *
 355  * \param vty Pointer to `vty` for outputting text.
 356  * \param json (optional) JSON object pointer.
 357  * \param bsp session parameters.
 358  */
 359 void bfd_sess_show(struct vty *vty, struct json_object *json,
 360                    struct bfd_session_params *bsp);
 361
 362 /**
 363  * Initializes the BFD integration library. This function executes the
 364  * following actions:
 365  *
 366  * - Copy the `struct thread_master` pointer to use as "thread" to execute
 367  *   the BFD session parameters installation.
 368  * - Copy the `struct zclient` pointer to install its callbacks.
 369  * - Initializes internal data structures.
 370  *
 371  * \param tm normally the daemon main thread event manager.
 372  * \param zc the zebra client of the daemon.
 373  */
 374 void bfd_protocol_integration_init(struct zclient *zc,
 375                                    struct thread_master *tm);
 376
 377 /**
 378  * BFD session registration arguments.
 379  */
 380 struct bfd_session_arg {
 381         /**
 382          * BFD command.
 383          *
 384          * Valid commands:
 385          * - `ZEBRA_BFD_DEST_REGISTER`
 386          * - `ZEBRA_BFD_DEST_DEREGISTER`
 387          */
 388         int32_t command;
 389
 390         /**
 391          * BFD family type.
 392          *
 393          * Supported types:
 394          * - `AF_INET`
 395          * - `AF_INET6`.
 396          */
 397         uint32_t family;
 398         /** Source address. */
 399         struct in6_addr src;
 400         /** Source address. */
 401         struct in6_addr dst;
 402
 403         /** Multi hop indicator. */
 404         uint8_t mhop;
 405         /** Expected hops. */
 406         uint8_t hops;
 407         /** C bit (Control Plane Independent bit) indicator. */
 408         uint8_t cbit;
 409
 410         /** Interface name size. */
 411         uint8_t ifnamelen;
 412         /** Interface name. */
 413         char ifname[64];
 414
 415         /** Daemon or session VRF. */
 416         vrf_id_t vrf_id;
 417
 418         /** Profile name length. */
 419         uint8_t profilelen;
 420         /** Profile name. */
 421         char profile[BFD_PROFILE_NAME_LEN];
 422
 423         /*
 424          * Deprecation fields: these fields should be removed once `ptm-bfd`
 425          * no longer uses this interface.
 426          */
 427
 428         /** Minimum required receive interval (in microseconds). */
 429         uint32_t min_rx;
 430         /** Minimum desired transmission interval (in microseconds). */
 431         uint32_t min_tx;
 432         /** Detection multiplier. */
 433         uint32_t detection_multiplier;
 434 };
 435
 436 /**
 437  * Send a message to BFD daemon through the zebra client.
 438  *
 439  * \param zc the zebra client context.
 440  * \param arg the BFD session command arguments.
 441  *
 442  * \returns `-1` on failure otherwise `0`.
 443  *
 444  * \see bfd_session_arg.
 445  */
 446 extern int zclient_bfd_command(struct zclient *zc, struct bfd_session_arg *arg);
 447
 448 /**
 449  * Enables or disables BFD protocol integration API debugging.
 450  *
 451  * \param enable new API debug state.
 452  */
 453 extern void bfd_protocol_integration_set_debug(bool enable);
 454
 455 /**
 456  * Sets shutdown mode so no more events are processed.
 457  *
 458  * This is useful to avoid the event storm that happens caused by network,
 459  * interfaces or VRFs removal. It should also avoid some crashes due hanging
 460  * pointers left overs by protocol.
 461  *
 462  * \param enable new API shutdown state.
 463  */
 464 extern void bfd_protocol_integration_set_shutdown(bool enable);
 465
 466 /**
 467  * Get API debugging state.
 468  */
 469 extern bool bfd_protocol_integration_debug(void);
 470
 471 /**
 472  * Get API shutdown state.
 473  */
 474 extern bool bfd_protocol_integration_shutting_down(void);
 475
 476 /* Update nexthop-tracking (nht) information for BFD auto source selection.
 477  * The function must be called from the daemon callback function
 478  * that deals with the ZEBRA_NEXTHOP_UPDATE zclient command
 479  */
 480 extern int bfd_nht_update(const struct prefix *match,
 481                           const struct zapi_route *route);
 482
 483 #ifdef __cplusplus
 484 }
 485 #endif
 486
 487 #endif /* _ZEBRA_BFD_H */