nest/protocol.h

   1 /*
   2  *      BIRD Internet Routing Daemon -- Protocols
   3  *
   4  *      (c) 1998--2000 Martin Mares <mj@ucw.cz>
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #ifndef _BIRD_PROTOCOL_H_
  10 #define _BIRD_PROTOCOL_H_
  11
  12 #include "lib/lists.h"
  13 #include "lib/resource.h"
  14 #include "lib/event.h"
  15 #include "nest/route.h"
  16 #include "conf/conf.h"
  17
  18 struct iface;
  19 struct ifa;
  20 struct rtable;
  21 struct rte;
  22 struct neighbor;
  23 struct rta;
  24 struct network;
  25 struct proto_config;
  26 struct channel_limit;
  27 struct channel_config;
  28 struct config;
  29 struct proto;
  30 struct channel;
  31 struct ea_list;
  32 struct eattr;
  33 struct symbol;
  34
  35
  36 /*
  37  *      Routing Protocol
  38  */
  39
  40 enum protocol_class {
  41   PROTOCOL_NONE,
  42   PROTOCOL_BABEL,
  43   PROTOCOL_BFD,
  44   PROTOCOL_BGP,
  45   PROTOCOL_DEVICE,
  46   PROTOCOL_DIRECT,
  47   PROTOCOL_KERNEL,
  48   PROTOCOL_OSPF,
  49   PROTOCOL_MRT,
  50   PROTOCOL_PERF,
  51   PROTOCOL_PIPE,
  52   PROTOCOL_RADV,
  53   PROTOCOL_RIP,
  54   PROTOCOL_RPKI,
  55   PROTOCOL_STATIC,
  56   PROTOCOL__MAX
  57 };
  58
  59 extern struct protocol *class_to_protocol[PROTOCOL__MAX];
  60
  61 struct protocol {
  62   node n;
  63   char *name;
  64   char *template;                       /* Template for automatic generation of names */
  65   int name_counter;                     /* Counter for automatic name generation */
  66   enum protocol_class class;            /* Machine readable protocol class */
  67   uint preference;                      /* Default protocol preference */
  68   uint channel_mask;                    /* Mask of accepted channel types (NB_*) */
  69   uint proto_size;                      /* Size of protocol data structure */
  70   uint config_size;                     /* Size of protocol config data structure */
  71
  72   void (*preconfig)(struct protocol *, struct config *);        /* Just before configuring */
  73   void (*postconfig)(struct proto_config *);                    /* After configuring each instance */
  74   struct proto * (*init)(struct proto_config *);                /* Create new instance */
  75   int (*reconfigure)(struct proto *, struct proto_config *);    /* Try to reconfigure instance, returns success */
  76   void (*dump)(struct proto *);                 /* Debugging dump */
  77   void (*dump_attrs)(struct rte *);             /* Dump protocol-dependent attributes */
  78   int (*start)(struct proto *);                 /* Start the instance */
  79   int (*shutdown)(struct proto *);              /* Stop the instance */
  80   void (*cleanup)(struct proto *);              /* Called after shutdown when protocol became hungry/down */
  81   void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */
  82   void (*get_route_info)(struct rte *, byte *buf); /* Get route information (for `show route' command) */
  83   int (*get_attr)(struct eattr *, byte *buf, int buflen);       /* ASCIIfy dynamic attribute (returns GA_*) */
  84   void (*show_proto_info)(struct proto *);      /* Show protocol info (for `show protocols all' command) */
  85   void (*copy_config)(struct proto_config *, struct proto_config *);    /* Copy config from given protocol instance */
  86 };
  87
  88 void protos_build(void);
  89 void proto_build(struct protocol *);
  90 void protos_preconfig(struct config *);
  91 void protos_commit(struct config *new, struct config *old, int force_restart, int type);
  92 struct proto * proto_spawn(struct proto_config *cf, uint disabled);
  93 void protos_dump_all(void);
  94
  95 #define GA_UNKNOWN      0               /* Attribute not recognized */
  96 #define GA_NAME         1               /* Result = name */
  97 #define GA_FULL         2               /* Result = both name and value */
  98
  99 /*
 100  *      Known protocols
 101  */
 102
 103 extern struct protocol
 104   proto_device, proto_radv, proto_rip, proto_static, proto_mrt,
 105   proto_ospf, proto_perf,
 106   proto_pipe, proto_bgp, proto_bfd, proto_babel, proto_rpki;
 107
 108 /*
 109  *      Routing Protocol Instance
 110  */
 111
 112 struct proto_config {
 113   node n;
 114   struct config *global;                /* Global configuration data */
 115   struct protocol *protocol;            /* Protocol */
 116   struct proto *proto;                  /* Instance we've created */
 117   struct proto_config *parent;          /* Parent proto_config for dynamic protocols */
 118   char *name;
 119   char *dsc;
 120   int class;                            /* SYM_PROTO or SYM_TEMPLATE */
 121   u8 net_type;                          /* Protocol network type (NET_*), 0 for undefined */
 122   u8 disabled;                          /* Protocol enabled/disabled by default */
 123   u32 debug, mrtdump;                   /* Debugging bitfields, both use D_* constants */
 124   u32 router_id;                        /* Protocol specific router ID */
 125
 126   list channels;                        /* List of channel configs (struct channel_config) */
 127   struct iface *vrf;                    /* Related VRF instance, NULL if global */
 128
 129   /* Check proto_reconfigure() and proto_copy_config() after changing struct proto_config */
 130
 131   /* Protocol-specific data follow... */
 132 };
 133
 134 /* Protocol statistics */
 135 struct proto_stats {
 136   /* Import - from protocol to core */
 137   u32 imp_routes;               /* Number of routes successfully imported to the (adjacent) routing table */
 138   u32 filt_routes;              /* Number of routes rejected in import filter but kept in the routing table */
 139   u32 pref_routes;              /* Number of routes selected as best in the (adjacent) routing table */
 140   u32 imp_updates_received;     /* Number of route updates received */
 141   u32 imp_updates_invalid;      /* Number of route updates rejected as invalid */
 142   u32 imp_updates_filtered;     /* Number of route updates rejected by filters */
 143   u32 imp_updates_ignored;      /* Number of route updates rejected as already in route table */
 144   u32 imp_updates_accepted;     /* Number of route updates accepted and imported */
 145   u32 imp_withdraws_received;   /* Number of route withdraws received */
 146   u32 imp_withdraws_invalid;    /* Number of route withdraws rejected as invalid */
 147   u32 imp_withdraws_ignored;    /* Number of route withdraws rejected as already not in route table */
 148   u32 imp_withdraws_accepted;   /* Number of route withdraws accepted and processed */
 149
 150   /* Export - from core to protocol */
 151   u32 exp_routes;               /* Number of routes successfully exported to the protocol */
 152   u32 exp_updates_received;     /* Number of route updates received */
 153   u32 exp_updates_rejected;     /* Number of route updates rejected by protocol */
 154   u32 exp_updates_filtered;     /* Number of route updates rejected by filters */
 155   u32 exp_updates_accepted;     /* Number of route updates accepted and exported */
 156   u32 exp_withdraws_received;   /* Number of route withdraws received */
 157   u32 exp_withdraws_accepted;   /* Number of route withdraws accepted and processed */
 158 };
 159
 160 struct proto {
 161   node n;                               /* Node in global proto_list */
 162   struct protocol *proto;               /* Protocol */
 163   struct proto_config *cf;              /* Configuration data */
 164   struct proto_config *cf_new;          /* Configuration we want to switch to after shutdown (NULL=delete) */
 165   pool *pool;                           /* Pool containing local objects */
 166   event *event;                         /* Protocol event */
 167
 168   list channels;                        /* List of channels to rtables (struct channel) */
 169   struct channel *main_channel;         /* Primary channel */
 170   struct rte_src *main_source;          /* Primary route source */
 171   struct iface *vrf;                    /* Related VRF instance, NULL if global */
 172
 173   char *name;                           /* Name of this instance (== cf->name) */
 174   u32 debug;                            /* Debugging flags */
 175   u32 mrtdump;                          /* MRTDump flags */
 176   uint active_channels;                 /* Number of active channels */
 177   byte net_type;                        /* Protocol network type (NET_*), 0 for undefined */
 178   byte disabled;                        /* Manually disabled */
 179   byte proto_state;                     /* Protocol state machine (PS_*, see below) */
 180   byte active;                          /* From PS_START to cleanup after PS_STOP */
 181   byte do_start;                        /* Start actions are scheduled */
 182   byte do_stop;                         /* Stop actions are scheduled */
 183   byte reconfiguring;                   /* We're shutting down due to reconfiguration */
 184   byte gr_recovery;                     /* Protocol should participate in graceful restart recovery */
 185   byte down_sched;                      /* Shutdown is scheduled for later (PDS_*) */
 186   byte down_code;                       /* Reason for shutdown (PDC_* codes) */
 187   u32 hash_key;                         /* Random key used for hashing of neighbors */
 188   btime last_state_change;              /* Time of last state transition */
 189   char *last_state_name_announced;      /* Last state name we've announced to the user */
 190   char *message;                        /* State-change message, allocated from proto_pool */
 191
 192   /*
 193    *    General protocol hooks:
 194    *
 195    *       if_notify    Notify protocol about interface state changes.
 196    *       ifa_notify   Notify protocol about interface address changes.
 197    *       rt_notify    Notify protocol about routing table updates.
 198    *       neigh_notify Notify protocol about neighbor cache events.
 199    *       make_tmp_attrs  Add attributes to rta from from private attrs stored in rte. The route and rta MUST NOT be cached.
 200    *       store_tmp_attrs Store private attrs back to rte and undef added attributes. The route and rta MUST NOT be cached.
 201    *       preexport  Called as the first step of the route exporting process.
 202    *                    It can construct a new rte, add private attributes and
 203    *                    decide whether the route shall be exported: 1=yes, -1=no,
 204    *                    0=process it through the export filter set by the user.
 205    *       reload_routes   Request channel to reload all its routes to the core
 206    *                    (using rte_update()). Returns: 0=reload cannot be done,
 207    *                    1= reload is scheduled and will happen (asynchronously).
 208    *       feed_begin   Notify channel about beginning of route feeding.
 209    *       feed_end     Notify channel about finish of route feeding.
 210    */
 211
 212   void (*if_notify)(struct proto *, unsigned flags, struct iface *i);
 213   void (*ifa_notify)(struct proto *, unsigned flags, struct ifa *a);
 214   void (*rt_notify)(struct proto *, struct channel *, struct network *net, struct rte *new, struct rte *old);
 215   void (*neigh_notify)(struct neighbor *neigh);
 216   void (*make_tmp_attrs)(struct rte *rt, struct linpool *pool);
 217   void (*store_tmp_attrs)(struct rte *rt, struct linpool *pool);
 218   int (*preexport)(struct proto *, struct rte **rt, struct linpool *pool);
 219   void (*reload_routes)(struct channel *);
 220   void (*feed_begin)(struct channel *, int initial);
 221   void (*feed_end)(struct channel *);
 222
 223   /*
 224    *    Routing entry hooks (called only for routes belonging to this protocol):
 225    *
 226    *       rte_recalculate Called at the beginning of the best route selection
 227    *       rte_better   Compare two rte's and decide which one is better (1=first, 0=second).
 228    *       rte_same     Compare two rte's and decide whether they are identical (1=yes, 0=no).
 229    *       rte_mergable Compare two rte's and decide whether they could be merged (1=yes, 0=no).
 230    *       rte_insert   Called whenever a rte is inserted to a routing table.
 231    *       rte_remove   Called whenever a rte is removed from the routing table.
 232    */
 233
 234   int (*rte_recalculate)(struct rtable *, struct network *, struct rte *, struct rte *, struct rte *);
 235   int (*rte_better)(struct rte *, struct rte *);
 236   int (*rte_same)(struct rte *, struct rte *);
 237   int (*rte_mergable)(struct rte *, struct rte *);
 238   struct rte * (*rte_modify)(struct rte *, struct linpool *);
 239   void (*rte_insert)(struct network *, struct rte *);
 240   void (*rte_remove)(struct network *, struct rte *);
 241
 242   /* Hic sunt protocol-specific data */
 243 };
 244
 245 struct proto_spec {
 246   void *ptr;
 247   int patt;
 248 };
 249
 250
 251 #define PDS_DISABLE             1       /* Proto disable scheduled */
 252 #define PDS_RESTART             2       /* Proto restart scheduled */
 253
 254 #define PDC_CF_REMOVE           0x01    /* Removed in new config */
 255 #define PDC_CF_DISABLE          0x02    /* Disabled in new config */
 256 #define PDC_CF_RESTART          0x03    /* Restart due to reconfiguration */
 257 #define PDC_CMD_DISABLE         0x11    /* Result of disable command */
 258 #define PDC_CMD_RESTART         0x12    /* Result of restart command */
 259 #define PDC_CMD_SHUTDOWN        0x13    /* Result of global shutdown */
 260 #define PDC_CMD_GR_DOWN         0x14    /* Result of global graceful restart */
 261 #define PDC_RX_LIMIT_HIT        0x21    /* Route receive limit reached */
 262 #define PDC_IN_LIMIT_HIT        0x22    /* Route import limit reached */
 263 #define PDC_OUT_LIMIT_HIT       0x23    /* Route export limit reached */
 264
 265
 266 void *proto_new(struct proto_config *);
 267 void *proto_config_new(struct protocol *, int class);
 268 void proto_copy_config(struct proto_config *dest, struct proto_config *src);
 269 void proto_clone_config(struct symbol *sym, struct proto_config *parent);
 270 void proto_set_message(struct proto *p, char *msg, int len);
 271
 272 void graceful_restart_recovery(void);
 273 void graceful_restart_init(void);
 274 void graceful_restart_show_status(void);
 275 void channel_graceful_restart_lock(struct channel *c);
 276 void channel_graceful_restart_unlock(struct channel *c);
 277
 278 #define DEFAULT_GR_WAIT 240
 279
 280 void channel_show_limit(struct channel_limit *l, const char *dsc);
 281 void channel_show_info(struct channel *c);
 282
 283 void proto_cmd_show(struct proto *, uintptr_t, int);
 284 void proto_cmd_disable(struct proto *, uintptr_t, int);
 285 void proto_cmd_enable(struct proto *, uintptr_t, int);
 286 void proto_cmd_restart(struct proto *, uintptr_t, int);
 287 void proto_cmd_reload(struct proto *, uintptr_t, int);
 288 void proto_cmd_debug(struct proto *, uintptr_t, int);
 289 void proto_cmd_mrtdump(struct proto *, uintptr_t, int);
 290
 291 void proto_apply_cmd(struct proto_spec ps, void (* cmd)(struct proto *, uintptr_t, int), int restricted, uintptr_t arg);
 292 struct proto *proto_get_named(struct symbol *, struct protocol *);
 293
 294 #define CMD_RELOAD      0
 295 #define CMD_RELOAD_IN   1
 296 #define CMD_RELOAD_OUT  2
 297
 298 static inline u32
 299 proto_get_router_id(struct proto_config *pc)
 300 {
 301   return pc->router_id ? pc->router_id : pc->global->router_id;
 302 }
 303
 304
 305 extern pool *proto_pool;
 306 extern list proto_list;
 307
 308 /*
 309  *  Each protocol instance runs two different state machines:
 310  *
 311  *  [P] The protocol machine: (implemented inside protocol)
 312  *
 313  *              DOWN    ---->    START
 314  *                ^                |
 315  *                |                V
 316  *              STOP    <----     UP
 317  *
 318  *      States: DOWN    Protocol is down and it's waiting for the core
 319  *                      requesting protocol start.
 320  *              START   Protocol is waiting for connection with the rest
 321  *                      of the network and it's not willing to accept
 322  *                      packets. When it connects, it goes to UP state.
 323  *              UP      Protocol is up and running. When the network
 324  *                      connection breaks down or the core requests
 325  *                      protocol to be terminated, it goes to STOP state.
 326  *              STOP    Protocol is disconnecting from the network.
 327  *                      After it disconnects, it returns to DOWN state.
 328  *
 329  *      In:     start() Called in DOWN state to request protocol startup.
 330  *                      Returns new state: either UP or START (in this
 331  *                      case, the protocol will notify the core when it
 332  *                      finally comes UP).
 333  *              stop()  Called in START, UP or STOP state to request
 334  *                      protocol shutdown. Returns new state: either
 335  *                      DOWN or STOP (in this case, the protocol will
 336  *                      notify the core when it finally comes DOWN).
 337  *
 338  *      Out:    proto_notify_state() -- called by protocol instance when
 339  *                      it does any state transition not covered by
 340  *                      return values of start() and stop(). This includes
 341  *                      START->UP (delayed protocol startup), UP->STOP
 342  *                      (spontaneous shutdown) and STOP->DOWN (delayed
 343  *                      shutdown).
 344  */
 345
 346 #define PS_DOWN 0
 347 #define PS_START 1
 348 #define PS_UP 2
 349 #define PS_STOP 3
 350
 351 void proto_notify_state(struct proto *p, unsigned state);
 352
 353 /*
 354  *  [F] The feeder machine: (implemented in core routines)
 355  *
 356  *              HUNGRY    ---->   FEEDING
 357  *               ^                   |
 358  *               |                   V
 359  *              FLUSHING  <----   HAPPY
 360  *
 361  *      States: HUNGRY  Protocol either administratively down (i.e.,
 362  *                      disabled by the user) or temporarily down
 363  *                      (i.e., [P] is not UP)
 364  *              FEEDING The protocol came up and we're feeding it
 365  *                      initial routes. [P] is UP.
 366  *              HAPPY   The protocol is up and it's receiving normal
 367  *                      routing updates. [P] is UP.
 368  *              FLUSHING The protocol is down and we're removing its
 369  *                      routes from the table. [P] is STOP or DOWN.
 370  *
 371  *      Normal lifecycle of a protocol looks like:
 372  *
 373  *              HUNGRY/DOWN --> HUNGRY/START --> HUNGRY/UP -->
 374  *              FEEDING/UP --> HAPPY/UP --> FLUSHING/STOP|DOWN -->
 375  *              HUNGRY/STOP|DOWN --> HUNGRY/DOWN
 376  *
 377  *      Sometimes, protocol might switch from HAPPY/UP to FEEDING/UP
 378  *      if it wants to refeed the routes (for example BGP does so
 379  *      as a result of received ROUTE-REFRESH request).
 380  */
 381
 382
 383
 384 /*
 385  *      Debugging flags
 386  */
 387
 388 #define D_STATES 1              /* [core] State transitions */
 389 #define D_ROUTES 2              /* [core] Routes passed by the filters */
 390 #define D_FILTERS 4             /* [core] Routes rejected by the filters */
 391 #define D_IFACES 8              /* [core] Interface events */
 392 #define D_EVENTS 16             /* Protocol events */
 393 #define D_PACKETS 32            /* Packets sent/received */
 394
 395 #ifndef PARSER
 396 #define TRACE(flags, msg, args...) \
 397   do { if (p->p.debug & flags) log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
 398 #endif
 399
 400
 401 /*
 402  *      MRTDump flags
 403  */
 404
 405 #define MD_STATES       1               /* Protocol state changes (BGP4MP_MESSAGE_AS4) */
 406 #define MD_MESSAGES     2               /* Protocol packets (BGP4MP_MESSAGE_AS4) */
 407
 408 /*
 409  *      Known unique protocol instances as referenced by config routines
 410  */
 411
 412 extern struct proto_config *cf_dev_proto;
 413
 414
 415 /*
 416  * Protocol limits
 417  */
 418
 419 #define PLD_RX          0       /* Receive limit */
 420 #define PLD_IN          1       /* Import limit */
 421 #define PLD_OUT         2       /* Export limit */
 422 #define PLD_MAX         3
 423
 424 #define PLA_NONE        0       /* No limit */
 425 #define PLA_WARN        1       /* Issue log warning */
 426 #define PLA_BLOCK       2       /* Block new routes */
 427 #define PLA_RESTART     4       /* Force protocol restart */
 428 #define PLA_DISABLE     5       /* Shutdown and disable protocol */
 429
 430 #define PLS_INITIAL     0       /* Initial limit state after protocol start */
 431 #define PLS_ACTIVE      1       /* Limit was hit */
 432 #define PLS_BLOCKED     2       /* Limit is active and blocking new routes */
 433
 434 struct channel_limit {
 435   u32 limit;                    /* Maximum number of prefixes */
 436   u8 action;                    /* Action to take (PLA_*) */
 437   u8 state;                     /* State of limit (PLS_*) */
 438 };
 439
 440 void channel_notify_limit(struct channel *c, struct channel_limit *l, int dir, u32 rt_count);
 441
 442
 443 /*
 444  *      Channels
 445  */
 446
 447 struct channel_class {
 448   uint channel_size;                    /* Size of channel data structure */
 449   uint config_size;                     /* Size of channel config data structure */
 450
 451   void (*init)(struct channel *, struct channel_config *);      /* Create new instance */
 452   int (*reconfigure)(struct channel *, struct channel_config *);        /* Try to reconfigure instance, returns success */
 453   int (*start)(struct channel *);       /* Start the instance */
 454   void (*shutdown)(struct channel *);   /* Stop the instance */
 455   void (*cleanup)(struct channel *);    /* Channel finished flush */
 456
 457   void (*copy_config)(struct channel_config *, struct channel_config *); /* Copy config from given channel instance */
 458 #if 0
 459   XXXX;
 460   void (*preconfig)(struct protocol *, struct config *);        /* Just before configuring */
 461   void (*postconfig)(struct proto_config *);                    /* After configuring each instance */
 462
 463
 464   void (*dump)(struct proto *);                 /* Debugging dump */
 465   void (*dump_attrs)(struct rte *);             /* Dump protocol-dependent attributes */
 466
 467   void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */
 468   void (*get_route_info)(struct rte *, byte *buf); /* Get route information (for `show route' command) */
 469   int (*get_attr)(struct eattr *, byte *buf, int buflen);       /* ASCIIfy dynamic attribute (returns GA_*) */
 470   void (*show_proto_info)(struct proto *);      /* Show protocol info (for `show protocols all' command) */
 471
 472 #endif
 473 };
 474
 475 extern struct channel_class channel_bgp;
 476
 477 struct channel_config {
 478   node n;
 479   const char *name;
 480   const struct channel_class *channel;
 481
 482   struct proto_config *parent;          /* Where channel is defined (proto or template) */
 483   struct rtable_config *table;          /* Table we're attached to */
 484   const struct filter *in_filter, *out_filter; /* Attached filters */
 485   struct channel_limit rx_limit;        /* Limit for receiving routes from protocol
 486                                            (relevant when in_keep_filtered is active) */
 487   struct channel_limit in_limit;        /* Limit for importing routes from protocol */
 488   struct channel_limit out_limit;       /* Limit for exporting routes to protocol */
 489
 490   u8 net_type;                          /* Routing table network type (NET_*), 0 for undefined */
 491   u8 ra_mode;                           /* Mode of received route advertisements (RA_*) */
 492   u16 preference;                       /* Default route preference */
 493   u8 merge_limit;                       /* Maximal number of nexthops for RA_MERGED */
 494   u8 in_keep_filtered;                  /* Routes rejected in import filter are kept */
 495 };
 496
 497 struct channel {
 498   node n;                               /* Node in proto->channels */
 499   node table_node;                      /* Node in table->channels */
 500
 501   const char *name;                     /* Channel name (may be NULL) */
 502   const struct channel_class *channel;
 503   struct proto *proto;
 504
 505   struct rtable *table;
 506   const struct filter *in_filter;       /* Input filter */
 507   const struct filter *out_filter;      /* Output filter */
 508   struct channel_limit rx_limit;        /* Receive limit (for in_keep_filtered) */
 509   struct channel_limit in_limit;        /* Input limit */
 510   struct channel_limit out_limit;       /* Output limit */
 511
 512   struct event *feed_event;             /* Event responsible for feeding */
 513   struct fib_iterator feed_fit;         /* Routing table iterator used during feeding */
 514   struct proto_stats stats;             /* Per-channel protocol statistics */
 515
 516   u8 net_type;                          /* Routing table network type (NET_*), 0 for undefined */
 517   u8 ra_mode;                           /* Mode of received route advertisements (RA_*) */
 518   u16 preference;                       /* Default route preference */
 519   u8 merge_limit;                       /* Maximal number of nexthops for RA_MERGED */
 520   u8 in_keep_filtered;                  /* Routes rejected in import filter are kept */
 521   u8 disabled;
 522   u8 stale;                             /* Used in reconfiguration */
 523
 524   u8 channel_state;
 525   u8 export_state;                      /* Route export state (ES_*, see below) */
 526   u8 feed_active;
 527   u8 flush_active;
 528   u8 refeeding;                         /* We are refeeding (valid only if export_state == ES_FEEDING) */
 529   u8 reloadable;                        /* Hook reload_routes() is allowed on the channel */
 530   u8 gr_lock;                           /* Graceful restart mechanism should wait for this channel */
 531   u8 gr_wait;                           /* Route export to channel is postponed until graceful restart */
 532
 533   btime last_state_change;              /* Time of last state transition */
 534   btime last_tx_filter_change;
 535
 536   struct rtable *in_table;              /* Internal table for received routes */
 537   struct event *reload_event;           /* Event responsible for reloading from in_table */
 538   struct fib_iterator reload_fit;       /* Iterator in in_table used during reloading */
 539   u8 reload_active;                     /* Iterator reload_fit is linked */
 540 };
 541
 542
 543 /*
 544  * Channel states
 545  *
 546  * CS_DOWN - The initial and the final state of a channel. There is no route
 547  * exchange between the protocol and the table. Channel is not counted as
 548  * active. Channel keeps a ptr to the table, but do not lock the table and is
 549  * not linked in the table. Generally, new closed channels are created in
 550  * protocols' init() hooks. The protocol is expected to explicitly activate its
 551  * channels (by calling channel_init() or channel_open()).
 552  *
 553  * CS_START - The channel as a connection between the protocol and the table is
 554  * initialized (counted as active by the protocol, linked in the table and keeps
 555  * the table locked), but there is no current route exchange. There still may be
 556  * routes associated with the channel in the routing table if the channel falls
 557  * to CS_START from CS_UP. Generally, channels are initialized in protocols'
 558  * start() hooks when going to PS_START.
 559  *
 560  * CS_UP - The channel is initialized and the route exchange is allowed. Note
 561  * that even in CS_UP state, route export may still be down (ES_DOWN) by the
 562  * core decision (e.g. waiting for table convergence after graceful restart).
 563  * I.e., the protocol decides to open the channel but the core decides to start
 564  * route export. Route import (caused by rte_update() from the protocol) is not
 565  * restricted by that and is on volition of the protocol. Generally, channels
 566  * are opened in protocols' start() hooks when going to PS_UP.
 567  *
 568  * CS_FLUSHING - The transitional state between initialized channel and closed
 569  * channel. The channel is still initialized, but no route exchange is allowed.
 570  * Instead, the associated table is running flush loop to remove routes imported
 571  * through the channel. After that, the channel changes state to CS_DOWN and
 572  * is detached from the table (the table is unlocked and the channel is unlinked
 573  * from it). Unlike other states, the CS_FLUSHING state is not explicitly
 574  * entered or left by the protocol. A protocol may request to close a channel
 575  * (by calling channel_close()), which causes the channel to change state to
 576  * CS_FLUSHING and later to CS_DOWN. Also note that channels are closed
 577  * automatically by the core when the protocol is going down.
 578  *
 579  * Allowed transitions:
 580  *
 581  * CS_DOWN      -> CS_START / CS_UP
 582  * CS_START     -> CS_UP / CS_FLUSHING
 583  * CS_UP        -> CS_START / CS_FLUSHING
 584  * CS_FLUSHING  -> CS_DOWN (automatic)
 585  */
 586
 587 #define CS_DOWN         0
 588 #define CS_START        1
 589 #define CS_UP           2
 590 #define CS_FLUSHING     3
 591
 592 #define ES_DOWN         0
 593 #define ES_FEEDING      1
 594 #define ES_READY        2
 595
 596
 597 struct channel_config *proto_cf_find_channel(struct proto_config *p, uint net_type);
 598 static inline struct channel_config *proto_cf_main_channel(struct proto_config *pc)
 599 { struct channel_config *cc = HEAD(pc->channels); return NODE_VALID(cc) ? cc : NULL; }
 600
 601 struct channel *proto_find_channel_by_table(struct proto *p, struct rtable *t);
 602 struct channel *proto_find_channel_by_name(struct proto *p, const char *n);
 603 struct channel *proto_add_channel(struct proto *p, struct channel_config *cf);
 604 int proto_configure_channel(struct proto *p, struct channel **c, struct channel_config *cf);
 605
 606 void channel_set_state(struct channel *c, uint state);
 607 void channel_setup_in_table(struct channel *c);
 608 void channel_schedule_reload(struct channel *c);
 609
 610 static inline void channel_init(struct channel *c) { channel_set_state(c, CS_START); }
 611 static inline void channel_open(struct channel *c) { channel_set_state(c, CS_UP); }
 612 static inline void channel_close(struct channel *c) { channel_set_state(c, CS_FLUSHING); }
 613
 614 void channel_request_feeding(struct channel *c);
 615 void *channel_config_new(const struct channel_class *cc, const char *name, uint net_type, struct proto_config *proto);
 616 void *channel_config_get(const struct channel_class *cc, const char *name, uint net_type, struct proto_config *proto);
 617 int channel_reconfigure(struct channel *c, struct channel_config *cf);
 618
 619
 620 /* Moved from route.h to avoid dependency conflicts */
 621 static inline void rte_update(struct proto *p, const net_addr *n, rte *new) { rte_update2(p->main_channel, n, new, p->main_source); }
 622
 623 static inline void
 624 rte_update3(struct channel *c, const net_addr *n, rte *new, struct rte_src *src)
 625 {
 626   if (c->in_table && !rte_update_in(c, n, new, src))
 627     return;
 628
 629   rte_update2(c, n, new, src);
 630 }
 631
 632
 633 #endif