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/timer.h"
  15 #include "conf/conf.h"
  16
  17 struct iface;
  18 struct ifa;
  19 struct rtable;
  20 struct rte;
  21 struct neighbor;
  22 struct rta;
  23 struct network;
  24 struct proto_config;
  25 struct config;
  26 struct proto;
  27 struct event;
  28 struct ea_list;
  29 struct eattr;
  30 struct symbol;
  31
  32 /*
  33  *      Routing Protocol
  34  */
  35
  36 struct protocol {
  37   node n;
  38   char *name;
  39   char *template;                       /* Template for automatic generation of names */
  40   int name_counter;                     /* Counter for automatic name generation */
  41   int attr_class;                       /* Attribute class known to this protocol */
  42   int multitable;                       /* Protocol handles all announce hooks itself */
  43   unsigned preference;                  /* Default protocol preference */
  44
  45   void (*preconfig)(struct protocol *, struct config *);        /* Just before configuring */
  46   void (*postconfig)(struct proto_config *);                    /* After configuring each instance */
  47   struct proto * (*init)(struct proto_config *);                /* Create new instance */
  48   int (*reconfigure)(struct proto *, struct proto_config *);    /* Try to reconfigure instance, returns success */
  49   void (*dump)(struct proto *);                 /* Debugging dump */
  50   void (*dump_attrs)(struct rte *);             /* Dump protocol-dependent attributes */
  51   int (*start)(struct proto *);                 /* Start the instance */
  52   int (*shutdown)(struct proto *);              /* Stop the instance */
  53   void (*cleanup)(struct proto *);              /* Called after shutdown when protocol became hungry/down */
  54   void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */
  55   void (*get_route_info)(struct rte *, byte *buf, struct ea_list *attrs); /* Get route information (for `show route' command) */
  56   int (*get_attr)(struct eattr *, byte *buf, int buflen);       /* ASCIIfy dynamic attribute (returns GA_*) */
  57   void (*show_proto_info)(struct proto *);      /* Show protocol info (for `show protocols all' command) */
  58   void (*copy_config)(struct proto_config *, struct proto_config *);    /* Copy config from given protocol instance */
  59 };
  60
  61 void protos_build(void);
  62 void proto_build(struct protocol *);
  63 void protos_preconfig(struct config *);
  64 void protos_postconfig(struct config *);
  65 void protos_commit(struct config *new, struct config *old, int force_restart, int type);
  66 void protos_dump_all(void);
  67
  68 #define GA_UNKNOWN      0               /* Attribute not recognized */
  69 #define GA_NAME         1               /* Result = name */
  70 #define GA_FULL         2               /* Result = both name and value */
  71
  72 /*
  73  *      Known protocols
  74  */
  75
  76 extern struct protocol
  77   proto_device, proto_radv, proto_rip, proto_static,
  78   proto_ospf, proto_pipe, proto_bgp;
  79
  80 /*
  81  *      Routing Protocol Instance
  82  */
  83
  84 struct proto_config {
  85   node n;
  86   struct config *global;                /* Global configuration data */
  87   struct protocol *protocol;            /* Protocol */
  88   struct proto *proto;                  /* Instance we've created */
  89   char *name;
  90   char *dsc;
  91   int class;                            /* SYM_PROTO or SYM_TEMPLATE */
  92   u32 debug, mrtdump;                   /* Debugging bitfields, both use D_* constants */
  93   unsigned preference, disabled;        /* Generic parameters */
  94   u32 router_id;                        /* Protocol specific router ID */
  95   struct rtable_config *table;          /* Table we're attached to */
  96   struct filter *in_filter, *out_filter; /* Attached filters */
  97   struct proto_limit *in_limit;         /* Limit for importing routes from protocol */
  98   struct proto_limit *out_limit;        /* Limit for exporting routes to protocol */
  99
 100   /* Check proto_reconfigure() and proto_copy_config() after changing struct proto_config */
 101
 102   /* Protocol-specific data follow... */
 103 };
 104
 105 /* Protocol statistics */
 106 struct proto_stats {
 107   /* Import - from protocol to core */
 108   u32 imp_routes;               /* Number of routes successfully imported to the (adjacent) routing table */
 109   u32 pref_routes;              /* Number of routes that are preferred, sum over all routing table */
 110   u32 imp_updates_received;     /* Number of route updates received */
 111   u32 imp_updates_invalid;      /* Number of route updates rejected as invalid */
 112   u32 imp_updates_filtered;     /* Number of route updates rejected by filters */
 113   u32 imp_updates_ignored;      /* Number of route updates rejected as already in route table */
 114   u32 imp_updates_accepted;     /* Number of route updates accepted and imported */
 115   u32 imp_withdraws_received;   /* Number of route withdraws received */
 116   u32 imp_withdraws_invalid;    /* Number of route withdraws rejected as invalid */
 117   u32 imp_withdraws_ignored;    /* Number of route withdraws rejected as already not in route table */
 118   u32 imp_withdraws_accepted;   /* Number of route withdraws accepted and processed */
 119
 120   /* Export - from core to protocol */
 121   u32 exp_routes;               /* Number of routes successfully exported to the protocol */
 122   u32 exp_updates_received;     /* Number of route updates received */
 123   u32 exp_updates_rejected;     /* Number of route updates rejected by protocol */
 124   u32 exp_updates_filtered;     /* Number of route updates rejected by filters */
 125   u32 exp_updates_accepted;     /* Number of route updates accepted and exported */
 126   u32 exp_withdraws_received;   /* Number of route withdraws received */
 127   u32 exp_withdraws_accepted;   /* Number of route withdraws accepted and processed */
 128 };
 129
 130 struct proto {
 131   node n;                               /* Node in *_proto_list */
 132   node glob_node;                       /* Node in global proto_list */
 133   struct protocol *proto;               /* Protocol */
 134   struct proto_config *cf;              /* Configuration data */
 135   struct proto_config *cf_new;          /* Configuration we want to switch to after shutdown (NULL=delete) */
 136   pool *pool;                           /* Pool containing local objects */
 137   struct event *attn;                   /* "Pay attention" event */
 138
 139   char *name;                           /* Name of this instance (== cf->name) */
 140   u32 debug;                            /* Debugging flags */
 141   u32 mrtdump;                          /* MRTDump flags */
 142   unsigned preference;                  /* Default route preference */
 143   byte accept_ra_types;                 /* Which types of route announcements are accepted (RA_OPTIMAL or RA_ANY) */
 144   byte disabled;                        /* Manually disabled */
 145   byte proto_state;                     /* Protocol state machine (PS_*, see below) */
 146   byte core_state;                      /* Core state machine (FS_*, see below) */
 147   byte core_goal;                       /* State we want to reach (FS_*, see below) */
 148   byte reconfiguring;                   /* We're shutting down due to reconfiguration */
 149   byte refeeding;                       /* We are refeeding (valid only if core_state == FS_FEEDING) */
 150   byte flushing;                        /* Protocol is flushed in current flush loop round */
 151   byte down_sched;                      /* Shutdown is scheduled for later (PDS_*) */
 152   byte down_code;                       /* Reason for shutdown (PDC_* codes) */
 153   u32 hash_key;                         /* Random key used for hashing of neighbors */
 154   bird_clock_t last_state_change;       /* Time of last state transition */
 155   char *last_state_name_announced;      /* Last state name we've announced to the user */
 156   struct proto_stats stats;             /* Current protocol statistics */
 157
 158   /*
 159    *    General protocol hooks:
 160    *
 161    *       if_notify    Notify protocol about interface state changes.
 162    *       ifa_notify   Notify protocol about interface address changes.
 163    *       rt_notify    Notify protocol about routing table updates.
 164    *       neigh_notify Notify protocol about neighbor cache events.
 165    *       make_tmp_attrs  Construct ea_list from private attrs stored in rte.
 166    *       store_tmp_attrs Store private attrs back to the rte.
 167    *       import_control  Called as the first step of the route importing process.
 168    *                    It can construct a new rte, add private attributes and
 169    *                    decide whether the route shall be imported: 1=yes, -1=no,
 170    *                    0=process it through the import filter set by the user.
 171    *       reload_routes   Request protocol to reload all its routes to the core
 172    *                    (using rte_update()). Returns: 0=reload cannot be done,
 173    *                    1= reload is scheduled and will happen (asynchronously).
 174    */
 175
 176   void (*if_notify)(struct proto *, unsigned flags, struct iface *i);
 177   void (*ifa_notify)(struct proto *, unsigned flags, struct ifa *a);
 178   void (*rt_notify)(struct proto *, struct rtable *table, struct network *net, struct rte *new, struct rte *old, struct ea_list *attrs);
 179   void (*neigh_notify)(struct neighbor *neigh);
 180   struct ea_list *(*make_tmp_attrs)(struct rte *rt, struct linpool *pool);
 181   void (*store_tmp_attrs)(struct rte *rt, struct ea_list *attrs);
 182   int (*import_control)(struct proto *, struct rte **rt, struct ea_list **attrs, struct linpool *pool);
 183   int (*reload_routes)(struct proto *);
 184
 185   /*
 186    *    Routing entry hooks (called only for rte's belonging to this protocol):
 187    *
 188    *       rte_recalculate Called at the beginning of the best route selection
 189    *       rte_better   Compare two rte's and decide which one is better (1=first, 0=second).
 190    *       rte_same     Compare two rte's and decide whether they are identical (1=yes, 0=no).
 191    *       rte_insert   Called whenever a rte is inserted to a routing table.
 192    *       rte_remove   Called whenever a rte is removed from the routing table.
 193    */
 194
 195   int (*rte_recalculate)(struct rtable *, struct network *, struct rte *, struct rte *, struct rte *);
 196   int (*rte_better)(struct rte *, struct rte *);
 197   int (*rte_same)(struct rte *, struct rte *);
 198   void (*rte_insert)(struct network *, struct rte *);
 199   void (*rte_remove)(struct network *, struct rte *);
 200
 201   struct rtable *table;                 /* Our primary routing table */
 202   struct announce_hook *main_ahook;     /* Primary announcement hook */
 203   struct announce_hook *ahooks;         /* Announcement hooks for this protocol */
 204
 205   struct fib_iterator *feed_iterator;   /* Routing table iterator used during protocol feeding */
 206   struct announce_hook *feed_ahook;     /* Announce hook we currently feed */
 207
 208   /* Hic sunt protocol-specific data */
 209 };
 210
 211 struct proto_spec {
 212   void *ptr;
 213   int patt;
 214 };
 215
 216
 217 #define PDS_DISABLE             1       /* Proto disable scheduled */
 218 #define PDS_RESTART             2       /* Proto restart scheduled */
 219
 220 #define PDC_CF_REMOVE           0x01    /* Removed in new config */
 221 #define PDC_CF_DISABLE          0x02    /* Disabled in new config */
 222 #define PDC_CF_RESTART          0x03    /* Restart due to reconfiguration */
 223 #define PDC_CMD_DISABLE         0x11    /* Result of disable command */
 224 #define PDC_CMD_RESTART         0x12    /* Result of restart command */
 225 #define PDC_IN_LIMIT_HIT        0x21    /* Route import limit reached */
 226 #define PDC_OUT_LIMIT_HIT       0x22    /* Route export limit reached - not implemented */
 227
 228
 229 void *proto_new(struct proto_config *, unsigned size);
 230 void *proto_config_new(struct protocol *, unsigned size, int class);
 231 void proto_copy_config(struct proto_config *dest, struct proto_config *src);
 232 void proto_request_feeding(struct proto *p);
 233
 234 static inline void
 235 proto_copy_rest(struct proto_config *dest, struct proto_config *src, unsigned size)
 236 { memcpy(dest + 1, src + 1, size - sizeof(struct proto_config)); }
 237
 238
 239 void proto_show_limit(struct proto_limit *l, const char *dsc);
 240 void proto_show_basic_info(struct proto *p);
 241
 242 void proto_cmd_show(struct proto *, unsigned int, int);
 243 void proto_cmd_disable(struct proto *, unsigned int, int);
 244 void proto_cmd_enable(struct proto *, unsigned int, int);
 245 void proto_cmd_restart(struct proto *, unsigned int, int);
 246 void proto_cmd_reload(struct proto *, unsigned int, int);
 247 void proto_cmd_debug(struct proto *, unsigned int, int);
 248 void proto_cmd_mrtdump(struct proto *, unsigned int, int);
 249
 250 void proto_apply_cmd(struct proto_spec ps, void (* cmd)(struct proto *, unsigned int, int), int restricted, unsigned int arg);
 251 struct proto *proto_get_named(struct symbol *, struct protocol *);
 252
 253 #define CMD_RELOAD      0
 254 #define CMD_RELOAD_IN   1
 255 #define CMD_RELOAD_OUT  2
 256
 257 static inline u32
 258 proto_get_router_id(struct proto_config *pc)
 259 {
 260   return pc->router_id ? pc->router_id : pc->global->router_id;
 261 }
 262
 263 extern list active_proto_list;
 264
 265 /*
 266  *  Each protocol instance runs two different state machines:
 267  *
 268  *  [P] The protocol machine: (implemented inside protocol)
 269  *
 270  *              DOWN    ---->    START
 271  *                ^                |
 272  *                |                V
 273  *              STOP    <----     UP
 274  *
 275  *      States: DOWN    Protocol is down and it's waiting for the core
 276  *                      requesting protocol start.
 277  *              START   Protocol is waiting for connection with the rest
 278  *                      of the network and it's not willing to accept
 279  *                      packets. When it connects, it goes to UP state.
 280  *              UP      Protocol is up and running. When the network
 281  *                      connection breaks down or the core requests
 282  *                      protocol to be terminated, it goes to STOP state.
 283  *              STOP    Protocol is disconnecting from the network.
 284  *                      After it disconnects, it returns to DOWN state.
 285  *
 286  *      In:     start() Called in DOWN state to request protocol startup.
 287  *                      Returns new state: either UP or START (in this
 288  *                      case, the protocol will notify the core when it
 289  *                      finally comes UP).
 290  *              stop()  Called in START, UP or STOP state to request
 291  *                      protocol shutdown. Returns new state: either
 292  *                      DOWN or STOP (in this case, the protocol will
 293  *                      notify the core when it finally comes DOWN).
 294  *
 295  *      Out:    proto_notify_state() -- called by protocol instance when
 296  *                      it does any state transition not covered by
 297  *                      return values of start() and stop(). This includes
 298  *                      START->UP (delayed protocol startup), UP->STOP
 299  *                      (spontaneous shutdown) and STOP->DOWN (delayed
 300  *                      shutdown).
 301  */
 302
 303 #define PS_DOWN 0
 304 #define PS_START 1
 305 #define PS_UP 2
 306 #define PS_STOP 3
 307
 308 void proto_notify_state(struct proto *p, unsigned state);
 309
 310 /*
 311  *  [F] The feeder machine: (implemented in core routines)
 312  *
 313  *              HUNGRY    ---->   FEEDING
 314  *               ^                   |
 315  *               |                   V
 316  *              FLUSHING  <----   HAPPY
 317  *
 318  *      States: HUNGRY  Protocol either administratively down (i.e.,
 319  *                      disabled by the user) or temporarily down
 320  *                      (i.e., [P] is not UP)
 321  *              FEEDING The protocol came up and we're feeding it
 322  *                      initial routes. [P] is UP.
 323  *              HAPPY   The protocol is up and it's receiving normal
 324  *                      routing updates. [P] is UP.
 325  *              FLUSHING The protocol is down and we're removing its
 326  *                      routes from the table. [P] is STOP or DOWN.
 327  *
 328  *      Normal lifecycle of a protocol looks like:
 329  *
 330  *              HUNGRY/DOWN --> HUNGRY/START --> HUNGRY/UP -->
 331  *              FEEDING/UP --> HAPPY/UP --> FLUSHING/STOP|DOWN -->
 332  *              HUNGRY/STOP|DOWN --> HUNGRY/DOWN
 333  *
 334  *      Sometimes, protocol might switch from HAPPY/UP to FEEDING/UP
 335  *      if it wants to refeed the routes (for example BGP does so
 336  *      as a result of received ROUTE-REFRESH request).
 337  */
 338
 339 #define FS_HUNGRY 0
 340 #define FS_FEEDING 1
 341 #define FS_HAPPY 2
 342 #define FS_FLUSHING 3
 343
 344 /*
 345  *      Debugging flags
 346  */
 347
 348 #define D_STATES 1              /* [core] State transitions */
 349 #define D_ROUTES 2              /* [core] Routes passed by the filters */
 350 #define D_FILTERS 4             /* [core] Routes rejected by the filters */
 351 #define D_IFACES 8              /* [core] Interface events */
 352 #define D_EVENTS 16             /* Protocol events */
 353 #define D_PACKETS 32            /* Packets sent/received */
 354
 355 /*
 356  *      MRTDump flags
 357  */
 358
 359 #define MD_STATES       1               /* Protocol state changes (BGP4MP_MESSAGE_AS4) */
 360 #define MD_MESSAGES     2               /* Protocol packets (BGP4MP_MESSAGE_AS4) */
 361
 362 /*
 363  *      Known unique protocol instances as referenced by config routines
 364  */
 365
 366 extern struct proto_config *cf_dev_proto;
 367
 368
 369 /*
 370  * Protocol limits
 371  */
 372
 373 #define PLA_WARN        1       /* Issue log warning */
 374 #define PLA_BLOCK       2       /* Block new routes */
 375 #define PLA_RESTART     4       /* Force protocol restart */
 376 #define PLA_DISABLE     5       /* Shutdown and disable protocol */
 377
 378 #define PLS_INITIAL     0       /* Initial limit state after protocol start */
 379 #define PLS_ACTIVE      1       /* Limit was hit */
 380 #define PLS_BLOCKED     2       /* Limit is active and blocking new routes */
 381
 382 struct proto_limit {
 383   u32 limit;                    /* Maximum number of prefixes */
 384   byte action;                  /* Action to take (PLA_*) */
 385   byte state;                   /* State of limit (PLS_*) */
 386 };
 387
 388 void proto_notify_limit(struct announce_hook *ah, struct proto_limit *l, u32 rt_count);
 389
 390 static inline void
 391 proto_reset_limit(struct proto_limit *l)
 392 {
 393   if (l)
 394     l->state = PLS_INITIAL;
 395 }
 396
 397
 398 /*
 399  *      Route Announcement Hook
 400  */
 401
 402 struct announce_hook {
 403   node n;
 404   struct rtable *table;
 405   struct proto *proto;
 406   struct filter *in_filter;             /* Input filter */
 407   struct filter *out_filter;            /* Output filter */
 408   struct proto_limit *in_limit;         /* Input limit */
 409   struct proto_limit *out_limit;        /* Output limit */
 410   struct proto_stats *stats;            /* Per-table protocol statistics */
 411   struct announce_hook *next;           /* Next hook for the same protocol */
 412 };
 413
 414 struct announce_hook *proto_add_announce_hook(struct proto *p, struct rtable *t, struct proto_stats *stats);
 415 struct announce_hook *proto_find_announce_hook(struct proto *p, struct rtable *t);
 416
 417 #endif