proto/bgp/bgp.h

   1 /*
   2  *      BIRD -- The Border Gateway Protocol
   3  *
   4  *      (c) 2000 Martin Mares <mj@ucw.cz>
   5  *      (c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
   6  *      (c) 2008--2016 CZ.NIC z.s.p.o.
   7  *
   8  *      Can be freely distributed and used under the terms of the GNU GPL.
   9  */
  10
  11 #ifndef _BIRD_BGP_H_
  12 #define _BIRD_BGP_H_
  13
  14 #include <stdint.h>
  15 #include <setjmp.h>
  16 #include "nest/bird.h"
  17 #include "nest/route.h"
  18 #include "nest/bfd.h"
  19 //#include "lib/lists.h"
  20 #include "lib/hash.h"
  21 #include "lib/socket.h"
  22
  23 struct linpool;
  24 struct eattr;
  25
  26
  27 /* Address families */
  28
  29 #define BGP_AFI_IPV4            1
  30 #define BGP_AFI_IPV6            2
  31
  32 #define BGP_SAFI_UNICAST        1
  33 #define BGP_SAFI_MULTICAST      2
  34 #define BGP_SAFI_MPLS           4
  35 #define BGP_SAFI_MPLS_VPN       128
  36 #define BGP_SAFI_VPN_MULTICAST  129
  37 #define BGP_SAFI_FLOW           133
  38
  39 /* Internal AF codes */
  40
  41 #define BGP_AF(A, B)            (((u32)(A) << 16) | (u32)(B))
  42 #define BGP_AFI(A)              ((u32)(A) >> 16)
  43 #define BGP_SAFI(A)             ((u32)(A) & 0xFFFF)
  44
  45 #define BGP_AF_IPV4             BGP_AF( BGP_AFI_IPV4, BGP_SAFI_UNICAST )
  46 #define BGP_AF_IPV6             BGP_AF( BGP_AFI_IPV6, BGP_SAFI_UNICAST )
  47 #define BGP_AF_IPV4_MC          BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MULTICAST )
  48 #define BGP_AF_IPV6_MC          BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MULTICAST )
  49 #define BGP_AF_IPV4_MPLS        BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS )
  50 #define BGP_AF_IPV6_MPLS        BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS )
  51 #define BGP_AF_VPN4_MPLS        BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS_VPN )
  52 #define BGP_AF_VPN6_MPLS        BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS_VPN )
  53 #define BGP_AF_VPN4_MC          BGP_AF( BGP_AFI_IPV4, BGP_SAFI_VPN_MULTICAST )
  54 #define BGP_AF_VPN6_MC          BGP_AF( BGP_AFI_IPV6, BGP_SAFI_VPN_MULTICAST )
  55 #define BGP_AF_FLOW4            BGP_AF( BGP_AFI_IPV4, BGP_SAFI_FLOW )
  56 #define BGP_AF_FLOW6            BGP_AF( BGP_AFI_IPV6, BGP_SAFI_FLOW )
  57
  58
  59 struct bgp_write_state;
  60 struct bgp_parse_state;
  61 struct bgp_export_state;
  62 struct bgp_bucket;
  63
  64 struct bgp_af_desc {
  65   u32 afi;
  66   u32 net;
  67   u8 mpls;
  68   u8 no_igp;
  69   const char *name;
  70   uint (*encode_nlri)(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size);
  71   void (*decode_nlri)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
  72   void (*update_next_hop)(struct bgp_export_state *s, eattr *nh, ea_list **to);
  73   uint (*encode_next_hop)(struct bgp_write_state *s, eattr *nh, byte *buf, uint size);
  74   void (*decode_next_hop)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
  75 };
  76
  77
  78 struct bgp_config {
  79   struct proto_config c;
  80   u32 local_as, remote_as;
  81   ip_addr local_ip;                     /* Source address to use */
  82   ip_addr remote_ip;
  83   struct iface *iface;                  /* Interface for link-local addresses */
  84   u16 local_port;                       /* Local listening port */
  85   u16 remote_port;                      /* Neighbor destination port */
  86   int multihop;                         /* Number of hops if multihop */
  87   int strict_bind;                      /* Bind listening socket to local address */
  88   int ttl_security;                     /* Enable TTL security [RFC 5082] */
  89   int compare_path_lengths;             /* Use path lengths when selecting best route */
  90   int med_metric;                       /* Compare MULTI_EXIT_DISC even between routes from differen ASes */
  91   int igp_metric;                       /* Use IGP metrics when selecting best route */
  92   int prefer_older;                     /* Prefer older routes according to RFC 5004 */
  93   int deterministic_med;                /* Use more complicated algo to have strict RFC 4271 MED comparison */
  94   u32 default_local_pref;               /* Default value for LOCAL_PREF attribute */
  95   u32 default_med;                      /* Default value for MULTI_EXIT_DISC attribute */
  96   int capabilities;                     /* Enable capability handshake [RFC 5492] */
  97   int enable_refresh;                   /* Enable local support for route refresh [RFC 2918] */
  98   int enable_as4;                       /* Enable local support for 4B AS numbers [RFC 6793] */
  99   int enable_extended_messages;         /* Enable local support for extended messages [draft] */
 100   u32 rr_cluster_id;                    /* Route reflector cluster ID, if different from local ID */
 101   int rr_client;                        /* Whether neighbor is RR client of me */
 102   int rs_client;                        /* Whether neighbor is RS client of me */
 103   u32 confederation;                    /* Confederation ID, or zero if confeds not active */
 104   int confederation_member;             /* Whether neighbor AS is member of our confederation */
 105   int passive;                          /* Do not initiate outgoing connection */
 106   int interpret_communities;            /* Hardwired handling of well-known communities */
 107   int allow_local_as;                   /* Allow that number of local ASNs in incoming AS_PATHs */
 108   int allow_local_pref;                 /* Allow LOCAL_PREF in EBGP sessions */
 109   int gr_mode;                          /* Graceful restart mode (BGP_GR_*) */
 110   int setkey;                           /* Set MD5 password to system SA/SP database */
 111   /* Times below are in seconds */
 112   unsigned gr_time;                     /* Graceful restart timeout */
 113   unsigned connect_delay_time;          /* Minimum delay between connect attempts */
 114   unsigned connect_retry_time;          /* Timeout for connect attempts */
 115   unsigned hold_time, initial_hold_time;
 116   unsigned keepalive_time;
 117   unsigned error_amnesia_time;          /* Errors are forgotten after */
 118   unsigned error_delay_time_min;        /* Time to wait after an error is detected */
 119   unsigned error_delay_time_max;
 120   unsigned disable_after_error;         /* Disable the protocol when error is detected */
 121
 122   char *password;                       /* Password used for MD5 authentication */
 123   int check_link;                       /* Use iface link state for liveness detection */
 124   int bfd;                              /* Use BFD for liveness detection */
 125 };
 126
 127 struct bgp_channel_config {
 128   struct channel_config c;
 129
 130   u32 afi;
 131   const struct bgp_af_desc *desc;
 132
 133   ip_addr next_hop_addr;                /* Local address for NEXT_HOP attribute */
 134   u8 next_hop_self;                     /* Always set next hop to local IP address */
 135   u8 next_hop_keep;                     /* Do not touch next hop attribute */
 136   u8 missing_lladdr;                    /* What we will do when we don' know link-local addr, see MLL_* */
 137   u8 gw_mode;                           /* How we compute route gateway from next_hop attr, see GW_* */
 138   u8 secondary;                         /* Accept also non-best routes (i.e. RA_ACCEPTED) */
 139   u8 gr_able;                           /* Allow full graceful restart for the channel */
 140   u8 ext_next_hop;                      /* Allow both IPv4 and IPv6 next hops */
 141   u8 add_path;                          /* Use ADD-PATH extension [RFC 7911] */
 142
 143   uint rest[0];                         /* Remaining items are reconfigured separately */
 144   struct rtable_config *igp_table_ip4;  /* Table for recursive IPv4 next hop lookups */
 145   struct rtable_config *igp_table_ip6;  /* Table for recursive IPv6 next hop lookups */
 146 };
 147
 148 #define MLL_SELF 1
 149 #define MLL_DROP 2
 150 #define MLL_IGNORE 3
 151
 152 #define GW_DIRECT 1
 153 #define GW_RECURSIVE 2
 154
 155 #define BGP_ADD_PATH_RX         1
 156 #define BGP_ADD_PATH_TX         2
 157 #define BGP_ADD_PATH_FULL       3
 158
 159 #define BGP_GR_ABLE             1
 160 #define BGP_GR_AWARE            2
 161
 162 /* For GR capability common flags */
 163 #define BGP_GRF_RESTART 0x80
 164
 165 /* For GR capability per-AF flags */
 166 #define BGP_GRF_FORWARDING 0x80
 167
 168
 169 struct bgp_af_caps {
 170   u32 afi;
 171   u8 ready;                             /* Multiprotocol capability, RFC 4760 */
 172   u8 gr_able;                           /* Graceful restart support, RFC 4724 */
 173   u8 gr_af_flags;                       /* Graceful restart per-AF flags */
 174   u8 ext_next_hop;                      /* Extended IPv6 next hop,   RFC 5549 */
 175   u8 add_path;                          /* Multiple paths support,   RFC 7911 */
 176 };
 177
 178 struct bgp_caps {
 179   u32 as4_number;                       /* Announced ASN */
 180
 181   u8 as4_support;                       /* Four-octet AS capability, RFC 6793 */
 182   u8 ext_messages;                      /* Extended message length,  RFC draft */
 183   u8 route_refresh;                     /* Route refresh capability, RFC 2918 */
 184   u8 enhanced_refresh;                  /* Enhanced route refresh,   RFC 7313 */
 185
 186   u8 gr_aware;                          /* Graceful restart capability, RFC 4724 */
 187   u8 gr_flags;                          /* Graceful restart flags */
 188   u16 gr_time;                          /* Graceful restart time in seconds */
 189
 190   u16 af_count;                         /* Number of af_data items */
 191
 192   struct bgp_af_caps af_data[0];        /* Per-AF capability data */
 193 };
 194
 195 #define WALK_AF_CAPS(caps,ac) \
 196   for (ac = caps->af_data; ac < &caps->af_data[caps->af_count]; ac++)
 197
 198
 199 struct bgp_socket {
 200   node n;                               /* Node in global bgp_sockets */
 201   sock *sk;                             /* Real listening socket */
 202   u32 uc;                               /* Use count */
 203 };
 204
 205 struct bgp_conn {
 206   struct bgp_proto *bgp;
 207   struct birdsock *sk;
 208   u8 state;                             /* State of connection state machine */
 209   u8 as4_session;                       /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
 210   u8 ext_messages;                      /* Session uses extended message length */
 211
 212   struct bgp_caps *local_caps;
 213   struct bgp_caps *remote_caps;
 214   timer *connect_timer;
 215   timer *hold_timer;
 216   timer *keepalive_timer;
 217   event *tx_ev;
 218   u32 packets_to_send;                  /* Bitmap of packet types to be sent */
 219   u32 channels_to_send;                 /* Bitmap of channels with packets to be sent */
 220   u8 last_channel;                      /* Channel used last time for TX */
 221   u8 last_channel_count;                /* Number of times the last channel was used in succession */
 222   int notify_code, notify_subcode, notify_size;
 223   byte *notify_data;
 224
 225   uint hold_time, keepalive_time;       /* Times calculated from my and neighbor's requirements */
 226 };
 227
 228 struct bgp_proto {
 229   struct proto p;
 230   struct bgp_config *cf;                /* Shortcut to BGP configuration */
 231   u32 local_as, remote_as;
 232   u32 public_as;                        /* Externally visible ASN (local_as or confederation id) */
 233   u32 local_id;                         /* BGP identifier of this router */
 234   u32 remote_id;                        /* BGP identifier of the neighbor */
 235   u32 rr_cluster_id;                    /* Route reflector cluster ID */
 236   int start_state;                      /* Substates that partitions BS_START */
 237   u8 is_internal;                       /* Internal BGP session (local_as == remote_as) */
 238   u8 is_interior;                       /* Internal or intra-confederation BGP session */
 239   u8 as4_session;                       /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
 240   u8 rr_client;                         /* Whether neighbor is RR client of me */
 241   u8 rs_client;                         /* Whether neighbor is RS client of me */
 242   u8 route_refresh;                     /* Route refresh allowed to send [RFC 2918] */
 243   u8 enhanced_refresh;                  /* Enhanced refresh is negotiated [RFC 7313] */
 244   u8 gr_ready;                          /* Neighbor could do graceful restart */
 245   u8 gr_active_num;                     /* Neighbor is doing GR, number of active channels */
 246   u8 channel_count;                     /* Number of active channels */
 247   u32 *afi_map;                         /* Map channel index -> AFI */
 248   struct bgp_channel **channel_map;     /* Map channel index -> channel */
 249   struct bgp_conn *conn;                /* Connection we have established */
 250   struct bgp_conn outgoing_conn;        /* Outgoing connection we're working with */
 251   struct bgp_conn incoming_conn;        /* Incoming connection we have neither accepted nor rejected yet */
 252   struct object_lock *lock;             /* Lock for neighbor connection */
 253   struct neighbor *neigh;               /* Neighbor entry corresponding to remote ip, NULL if multihop */
 254   struct bgp_socket *sock;              /* Shared listening socket */
 255   struct bfd_request *bfd_req;          /* BFD request, if BFD is used */
 256   ip_addr source_addr;                  /* Local address used as an advertised next hop */
 257   ip_addr link_addr;                    /* Link-local version of source_addr */
 258   event *event;                         /* Event for respawning and shutting process */
 259   timer *startup_timer;                 /* Timer used to delay protocol startup due to previous errors (startup_delay) */
 260   timer *gr_timer;                      /* Timer waiting for reestablishment after graceful restart */
 261   uint startup_delay;                   /* Delay (in seconds) of protocol startup due to previous errors */
 262   btime last_proto_error;               /* Time of last error that leads to protocol stop */
 263   u8 last_error_class;                  /* Error class of last error */
 264   u32 last_error_code;                  /* Error code of last error. BGP protocol errors
 265                                            are encoded as (bgp_err_code << 16 | bgp_err_subcode) */
 266 };
 267
 268 struct bgp_channel {
 269   struct channel c;
 270
 271   /* Rest are BGP specific data */
 272   struct bgp_channel_config *cf;
 273   pool *pool; /* XXXX */
 274
 275   u32 afi;
 276   u32 index;
 277   const struct bgp_af_desc *desc;
 278
 279   HASH(struct bgp_bucket) bucket_hash;  /* Hash table of route buckets */
 280   struct bgp_bucket *withdraw_bucket;   /* Withdrawn routes */
 281   list bucket_queue;                    /* Queue of buckets to send (struct bgp_bucket) */
 282
 283   HASH(struct bgp_prefix) prefix_hash;  /* Prefixes to be sent */
 284   slab *prefix_slab;                    /* Slab holding prefix nodes */
 285
 286   rtable *igp_table_ip4;                /* Table for recursive IPv4 next hop lookups */
 287   rtable *igp_table_ip6;                /* Table for recursive IPv6 next hop lookups */
 288   ip_addr next_hop_addr;                /* Local address for NEXT_HOP attribute */
 289   ip_addr link_addr;                    /* Link-local version of next_hop_addr */
 290
 291   u32 packets_to_send;                  /* Bitmap of packet types to be sent */
 292
 293   u8 gr_ready;                          /* Neighbor could do GR on this AF */
 294   u8 gr_active;                         /* Neighbor is doing GR and keeping fwd state */
 295
 296   u8 ext_next_hop;                      /* Session allows both IPv4 and IPv6 next hops */
 297
 298   u8 add_path_rx;                       /* Session expects receive of ADD-PATH extended NLRI */
 299   u8 add_path_tx;                       /* Session expects transmit of ADD-PATH extended NLRI */
 300
 301   u8 feed_state;                        /* Feed state (TX) for EoR, RR packets, see BFS_* */
 302   u8 load_state;                        /* Load state (RX) for EoR, RR packets, see BFS_* */
 303 };
 304
 305 struct bgp_prefix {
 306   node buck_node;                       /* Node in per-bucket list */
 307   struct bgp_prefix *next;              /* Node in prefix hash table */
 308   u32 hash;
 309   u32 path_id;
 310   net_addr net[0];
 311 };
 312
 313 struct bgp_bucket {
 314   node send_node;                       /* Node in send queue */
 315   struct bgp_bucket *next;              /* Node in bucket hash table */
 316   list prefixes;                        /* Prefixes in this bucket (struct bgp_prefix) */
 317   u32 hash;                             /* Hash over extended attributes */
 318   ea_list eattrs[0];                    /* Per-bucket extended attributes */
 319 };
 320
 321 struct bgp_export_state {
 322   struct bgp_proto *proto;
 323   struct bgp_channel *channel;
 324   struct linpool *pool;
 325
 326   struct bgp_proto *src;
 327   rte *route;
 328   int mpls;
 329
 330   u32 attrs_seen[1];
 331   uint err_withdraw;
 332 };
 333
 334 struct bgp_write_state {
 335   struct bgp_proto *proto;
 336   struct bgp_channel *channel;
 337   struct linpool *pool;
 338
 339   int as4_session;
 340   int add_path;
 341   int mpls;
 342
 343   eattr *mp_next_hop;
 344   adata *mpls_labels;
 345 };
 346
 347 struct bgp_parse_state {
 348   struct bgp_proto *proto;
 349   struct bgp_channel *channel;
 350   struct linpool *pool;
 351
 352   int as4_session;
 353   int add_path;
 354   int mpls;
 355
 356   u32 attrs_seen[256/32];
 357
 358   u32 mp_reach_af;
 359   u32 mp_unreach_af;
 360
 361   uint attr_len;
 362   uint ip_reach_len;
 363   uint ip_unreach_len;
 364   uint ip_next_hop_len;
 365   uint mp_reach_len;
 366   uint mp_unreach_len;
 367   uint mp_next_hop_len;
 368
 369   byte *attrs;
 370   byte *ip_reach_nlri;
 371   byte *ip_unreach_nlri;
 372   byte *ip_next_hop_data;
 373   byte *mp_reach_nlri;
 374   byte *mp_unreach_nlri;
 375   byte *mp_next_hop_data;
 376
 377   uint err_withdraw;
 378   uint err_subcode;
 379   jmp_buf err_jmpbuf;
 380
 381   struct hostentry *hostentry;
 382   adata *mpls_labels;
 383
 384   /* Cached state for bgp_rte_update() */
 385   u32 last_id;
 386   struct rte_src *last_src;
 387   rta *cached_rta;
 388 };
 389
 390 #define BGP_PORT                179
 391 #define BGP_VERSION             4
 392 #define BGP_HEADER_LENGTH       19
 393 #define BGP_MAX_MESSAGE_LENGTH  4096
 394 #define BGP_MAX_EXT_MSG_LENGTH  65535
 395 #define BGP_RX_BUFFER_SIZE      4096
 396 #define BGP_TX_BUFFER_SIZE      4096
 397 #define BGP_RX_BUFFER_EXT_SIZE  65535
 398 #define BGP_TX_BUFFER_EXT_SIZE  65535
 399
 400 static inline int bgp_channel_is_ipv4(struct bgp_channel *c)
 401 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
 402
 403 static inline int bgp_channel_is_ipv6(struct bgp_channel *c)
 404 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
 405
 406 static inline int bgp_cc_is_ipv4(struct bgp_channel_config *c)
 407 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
 408
 409 static inline int bgp_cc_is_ipv6(struct bgp_channel_config *c)
 410 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
 411
 412 static inline uint bgp_max_packet_length(struct bgp_conn *conn)
 413 { return conn->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
 414
 415 static inline void
 416 bgp_parse_error(struct bgp_parse_state *s, uint subcode)
 417 {
 418   s->err_subcode = subcode;
 419   longjmp(s->err_jmpbuf, 1);
 420 }
 421
 422 extern struct linpool *bgp_linpool;
 423 extern struct linpool *bgp_linpool2;
 424
 425
 426 void bgp_start_timer(timer *t, uint value);
 427 void bgp_check_config(struct bgp_config *c);
 428 void bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int len);
 429 void bgp_close_conn(struct bgp_conn *c);
 430 void bgp_update_startup_delay(struct bgp_proto *p);
 431 void bgp_conn_enter_openconfirm_state(struct bgp_conn *conn);
 432 void bgp_conn_enter_established_state(struct bgp_conn *conn);
 433 void bgp_conn_enter_close_state(struct bgp_conn *conn);
 434 void bgp_conn_enter_idle_state(struct bgp_conn *conn);
 435 void bgp_handle_graceful_restart(struct bgp_proto *p);
 436 void bgp_graceful_restart_done(struct bgp_channel *c);
 437 void bgp_refresh_begin(struct bgp_channel *c);
 438 void bgp_refresh_end(struct bgp_channel *c);
 439 void bgp_store_error(struct bgp_proto *p, struct bgp_conn *c, u8 class, u32 code);
 440 void bgp_stop(struct bgp_proto *p, unsigned subcode);
 441
 442 struct rte_source *bgp_find_source(struct bgp_proto *p, u32 path_id);
 443 struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
 444
 445
 446
 447 #ifdef LOCAL_DEBUG
 448 #define BGP_FORCE_DEBUG 1
 449 #else
 450 #define BGP_FORCE_DEBUG 0
 451 #endif
 452 #define BGP_TRACE(flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
 453         log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
 454
 455 #define BGP_TRACE_RL(rl, flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
 456         log_rl(rl, L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
 457
 458
 459 /* attrs.c */
 460
 461 static inline eattr *
 462 bgp_find_attr(ea_list *attrs, uint code)
 463 {
 464   return ea_find(attrs, EA_CODE(EAP_BGP, code));
 465 }
 466
 467 eattr *
 468 bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val);
 469
 470 static inline void
 471 bgp_set_attr_u32(ea_list **to, struct linpool *pool, uint code, uint flags, u32 val)
 472 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
 473
 474 static inline void
 475 bgp_set_attr_ptr(ea_list **to, struct linpool *pool, uint code, uint flags, struct adata *val)
 476 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
 477
 478 static inline void
 479 bgp_set_attr_data(ea_list **to, struct linpool *pool, uint code, uint flags, void *data, uint len)
 480 {
 481   struct adata *a = lp_alloc_adata(pool, len);
 482   memcpy(a->data, data, len);
 483   bgp_set_attr(to, pool, code, flags, (uintptr_t) a);
 484 }
 485
 486 static inline void
 487 bgp_unset_attr(ea_list **to, struct linpool *pool, uint code)
 488 { eattr *e = bgp_set_attr(to, pool, code, 0, 0); e->type = EAF_TYPE_UNDEF; }
 489
 490
 491 int bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end);
 492 ea_list * bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len);
 493
 494 void bgp_init_bucket_table(struct bgp_channel *c);
 495 void bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b);
 496 void bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b);
 497 void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
 498
 499 void bgp_init_prefix_table(struct bgp_channel *c);
 500 void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
 501
 502 int bgp_rte_better(struct rte *, struct rte *);
 503 int bgp_rte_mergable(rte *pri, rte *sec);
 504 int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
 505 void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old, ea_list *attrs);
 506 int bgp_import_control(struct proto *, struct rte **, struct ea_list **, struct linpool *);
 507 int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
 508 void bgp_get_route_info(struct rte *, byte *buf, struct ea_list *attrs);
 509
 510
 511 /* packets.c */
 512
 513 void mrt_dump_bgp_state_change(struct bgp_conn *conn, unsigned old, unsigned new);
 514 const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
 515 const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
 516 void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
 517 void bgp_kick_tx(void *vconn);
 518 void bgp_tx(struct birdsock *sk);
 519 int bgp_rx(struct birdsock *sk, uint size);
 520 const char * bgp_error_dsc(unsigned code, unsigned subcode);
 521 void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
 522
 523 void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
 524
 525
 526 /* Packet types */
 527
 528 #define PKT_OPEN                0x01
 529 #define PKT_UPDATE              0x02
 530 #define PKT_NOTIFICATION        0x03
 531 #define PKT_KEEPALIVE           0x04
 532 #define PKT_ROUTE_REFRESH       0x05    /* [RFC2918] */
 533 #define PKT_BEGIN_REFRESH       0x1e    /* Dummy type for BoRR packet [RFC7313] */
 534 #define PKT_SCHEDULE_CLOSE      0x1f    /* Used internally to schedule socket close */
 535
 536 /* Attributes */
 537
 538 #define BAF_OPTIONAL            0x80
 539 #define BAF_TRANSITIVE          0x40
 540 #define BAF_PARTIAL             0x20
 541 #define BAF_EXT_LEN             0x10
 542
 543 #define BA_ORIGIN               0x01    /* RFC 4271 */          /* WM */
 544 #define BA_AS_PATH              0x02                            /* WM */
 545 #define BA_NEXT_HOP             0x03                            /* WM */
 546 #define BA_MULTI_EXIT_DISC      0x04                            /* ON */
 547 #define BA_LOCAL_PREF           0x05                            /* WD */
 548 #define BA_ATOMIC_AGGR          0x06                            /* WD */
 549 #define BA_AGGREGATOR           0x07                            /* OT */
 550 #define BA_COMMUNITY            0x08    /* RFC 1997 */          /* OT */
 551 #define BA_ORIGINATOR_ID        0x09    /* RFC 4456 */          /* ON */
 552 #define BA_CLUSTER_LIST         0x0a    /* RFC 4456 */          /* ON */
 553 #define BA_MP_REACH_NLRI        0x0e    /* RFC 4760 */
 554 #define BA_MP_UNREACH_NLRI      0x0f    /* RFC 4760 */
 555 #define BA_EXT_COMMUNITY        0x10    /* RFC 4360 */
 556 #define BA_AS4_PATH             0x11    /* RFC 6793 */
 557 #define BA_AS4_AGGREGATOR       0x12    /* RFC 6793 */
 558 #define BA_LARGE_COMMUNITY      0x20    /* RFC 8092 */
 559
 560 /* Bird's private internal BGP attributes */
 561 #define BA_MPLS_LABEL_STACK     0xfe    /* MPLS label stack transfer attribute */
 562
 563 /* BGP connection states */
 564
 565 #define BS_IDLE                 0
 566 #define BS_CONNECT              1       /* Attempting to connect */
 567 #define BS_ACTIVE               2       /* Waiting for connection retry & listening */
 568 #define BS_OPENSENT             3
 569 #define BS_OPENCONFIRM          4
 570 #define BS_ESTABLISHED          5
 571 #define BS_CLOSE                6       /* Used during transition to BS_IDLE */
 572
 573 #define BS_MAX                  7
 574
 575 /* BGP start states
 576  *
 577  * Used in PS_START for fine-grained specification of starting state.
 578  *
 579  * When BGP protocol is started by core, it goes to BSS_PREPARE. When BGP
 580  * protocol done what is neccessary to start itself (like acquiring the lock),
 581  * it goes to BSS_CONNECT.
 582  */
 583
 584 #define BSS_PREPARE             0       /* Used before ordinary BGP started, i. e. waiting for lock */
 585 #define BSS_DELAY               1       /* Startup delay due to previous errors */
 586 #define BSS_CONNECT             2       /* Ordinary BGP connecting */
 587
 588
 589 /* BGP feed states (TX)
 590  *
 591  * RFC 4724 specifies that an initial feed should end with End-of-RIB mark.
 592  *
 593  * RFC 7313 specifies that a route refresh should be demarcated by BoRR and EoRR packets.
 594  *
 595  * These states (stored in c->feed_state) are used to keep track of these
 596  * requirements. When such feed is started, BFS_LOADING / BFS_REFRESHING is
 597  * set. When it ended, BFS_LOADED / BFS_REFRESHED is set to schedule End-of-RIB
 598  * or EoRR packet. When the packet is sent, the state returned to BFS_NONE.
 599  *
 600  * Note that when a non-demarcated feed (e.g. plain RFC 4271 initial load
 601  * without End-of-RIB or plain RFC 2918 route refresh without BoRR/EoRR
 602  * demarcation) is active, BFS_NONE is set.
 603  *
 604  * BFS_NONE, BFS_LOADING and BFS_REFRESHING are also used as load states (RX)
 605  * with correspondent semantics (-, expecting End-of-RIB, expecting EoRR).
 606  */
 607
 608 #define BFS_NONE                0       /* No feed or original non-demarcated feed */
 609 #define BFS_LOADING             1       /* Initial feed active, End-of-RIB planned */
 610 #define BFS_LOADED              2       /* Loading done, End-of-RIB marker scheduled */
 611 #define BFS_REFRESHING          3       /* Route refresh (introduced by BoRR) active */
 612 #define BFS_REFRESHED           4       /* Refresh done, EoRR packet scheduled */
 613
 614
 615 /* Error classes */
 616
 617 #define BE_NONE                 0
 618 #define BE_MISC                 1       /* Miscellaneous error */
 619 #define BE_SOCKET               2       /* Socket error */
 620 #define BE_BGP_RX               3       /* BGP protocol error notification received */
 621 #define BE_BGP_TX               4       /* BGP protocol error notification sent */
 622 #define BE_AUTO_DOWN            5       /* Automatic shutdown */
 623 #define BE_MAN_DOWN             6       /* Manual shutdown */
 624
 625 /* Misc error codes */
 626
 627 #define BEM_NEIGHBOR_LOST       1
 628 #define BEM_INVALID_NEXT_HOP    2
 629 #define BEM_INVALID_MD5         3       /* MD5 authentication kernel request failed (possibly not supported) */
 630 #define BEM_NO_SOCKET           4
 631 #define BEM_LINK_DOWN           5
 632 #define BEM_BFD_DOWN            6
 633 #define BEM_GRACEFUL_RESTART    7
 634
 635 /* Automatic shutdown error codes */
 636
 637 #define BEA_ROUTE_LIMIT_EXCEEDED 1
 638
 639 /* Well-known communities */
 640
 641 #define BGP_COMM_NO_EXPORT              0xffffff01      /* Don't export outside local AS / confed. */
 642 #define BGP_COMM_NO_ADVERTISE           0xffffff02      /* Don't export at all */
 643 #define BGP_COMM_NO_EXPORT_SUBCONFED    0xffffff03      /* NO_EXPORT even in local confederation */
 644
 645 /* Origins */
 646
 647 #define ORIGIN_IGP              0
 648 #define ORIGIN_EGP              1
 649 #define ORIGIN_INCOMPLETE       2
 650
 651
 652 #endif