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[thirdparty/bird.git] / 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 peer_type; /* Internal or external BGP (BGP_PT_*, optional) */
87 int multihop; /* Number of hops if multihop */
88 int strict_bind; /* Bind listening socket to local address */
89 int ttl_security; /* Enable TTL security [RFC 5082] */
90 int compare_path_lengths; /* Use path lengths when selecting best route */
91 int med_metric; /* Compare MULTI_EXIT_DISC even between routes from differen ASes */
92 int igp_metric; /* Use IGP metrics when selecting best route */
93 int prefer_older; /* Prefer older routes according to RFC 5004 */
94 int deterministic_med; /* Use more complicated algo to have strict RFC 4271 MED comparison */
95 u32 default_local_pref; /* Default value for LOCAL_PREF attribute */
96 u32 default_med; /* Default value for MULTI_EXIT_DISC attribute */
97 int capabilities; /* Enable capability handshake [RFC 5492] */
98 int enable_refresh; /* Enable local support for route refresh [RFC 2918] */
99 int enable_as4; /* Enable local support for 4B AS numbers [RFC 6793] */
100 int enable_extended_messages; /* Enable local support for extended messages [draft] */
101 u32 rr_cluster_id; /* Route reflector cluster ID, if different from local ID */
102 int rr_client; /* Whether neighbor is RR client of me */
103 int rs_client; /* Whether neighbor is RS client of me */
104 u32 confederation; /* Confederation ID, or zero if confeds not active */
105 int confederation_member; /* Whether neighbor AS is member of our confederation */
106 int passive; /* Do not initiate outgoing connection */
107 int interpret_communities; /* Hardwired handling of well-known communities */
108 int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */
109 int allow_local_pref; /* Allow LOCAL_PREF in EBGP sessions */
110 int gr_mode; /* Graceful restart mode (BGP_GR_*) */
111 int llgr_mode; /* Long-lived graceful restart mode (BGP_LLGR_*) */
112 int setkey; /* Set MD5 password to system SA/SP database */
113 /* Times below are in seconds */
114 unsigned gr_time; /* Graceful restart timeout */
115 unsigned llgr_time; /* Long-lived graceful restart stale time */
116 unsigned connect_delay_time; /* Minimum delay between connect attempts */
117 unsigned connect_retry_time; /* Timeout for connect attempts */
118 unsigned hold_time, initial_hold_time;
119 unsigned keepalive_time;
120 unsigned error_amnesia_time; /* Errors are forgotten after */
121 unsigned error_delay_time_min; /* Time to wait after an error is detected */
122 unsigned error_delay_time_max;
123 unsigned disable_after_error; /* Disable the protocol when error is detected */
124 u32 disable_after_cease; /* Disable it when cease is received, bitfield */
125
126 char *password; /* Password used for MD5 authentication */
127 int check_link; /* Use iface link state for liveness detection */
128 int bfd; /* Use BFD for liveness detection */
129 };
130
131 struct bgp_channel_config {
132 struct channel_config c;
133
134 u32 afi;
135 const struct bgp_af_desc *desc;
136
137 ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
138 u8 next_hop_self; /* Always set next hop to local IP address (NH_*) */
139 u8 next_hop_keep; /* Do not modify next hop attribute (NH_*) */
140 u8 mandatory; /* Channel is mandatory in capability negotiation */
141 u8 missing_lladdr; /* What we will do when we don' know link-local addr, see MLL_* */
142 u8 gw_mode; /* How we compute route gateway from next_hop attr, see GW_* */
143 u8 secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */
144 u8 gr_able; /* Allow full graceful restart for the channel */
145 u8 llgr_able; /* Allow full long-lived GR for the channel */
146 uint llgr_time; /* Long-lived graceful restart stale time */
147 u8 ext_next_hop; /* Allow both IPv4 and IPv6 next hops */
148 u8 add_path; /* Use ADD-PATH extension [RFC 7911] */
149 u8 import_table; /* Use c.in_table as Adj-RIB-In */
150
151 uint rest[0]; /* Remaining items are reconfigured separately */
152 struct rtable_config *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
153 struct rtable_config *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
154 };
155
156 #define BGP_PT_INTERNAL 1
157 #define BGP_PT_EXTERNAL 2
158
159 #define NH_NO 0
160 #define NH_ALL 1
161 #define NH_IBGP 2
162 #define NH_EBGP 3
163
164 #define MLL_SELF 1
165 #define MLL_DROP 2
166 #define MLL_IGNORE 3
167
168 #define GW_DIRECT 1
169 #define GW_RECURSIVE 2
170
171 #define BGP_ADD_PATH_RX 1
172 #define BGP_ADD_PATH_TX 2
173 #define BGP_ADD_PATH_FULL 3
174
175 #define BGP_GR_ABLE 1
176 #define BGP_GR_AWARE 2
177
178 /* For GR capability common flags */
179 #define BGP_GRF_RESTART 0x80
180
181 /* For GR capability per-AF flags */
182 #define BGP_GRF_FORWARDING 0x80
183
184 #define BGP_LLGR_ABLE 1
185 #define BGP_LLGR_AWARE 2
186
187 #define BGP_LLGRF_FORWARDING 0x80
188
189 #define BGP_GRS_NONE 0 /* No GR */
190 #define BGP_GRS_ACTIVE 1 /* Graceful restart per RFC 4724 */
191 #define BGP_GRS_LLGR 2 /* Long-lived GR phase (stale timer active) */
192
193 #define BGP_BFD_GRACEFUL 2 /* BFD down triggers graceful restart */
194
195
196 struct bgp_af_caps {
197 u32 afi;
198 u8 ready; /* Multiprotocol capability, RFC 4760 */
199 u8 gr_able; /* Graceful restart support, RFC 4724 */
200 u8 gr_af_flags; /* Graceful restart per-AF flags */
201 u8 llgr_able; /* Long-lived GR, RFC draft */
202 u32 llgr_time; /* Long-lived GR stale time */
203 u8 llgr_flags; /* Long-lived GR per-AF flags */
204 u8 ext_next_hop; /* Extended IPv6 next hop, RFC 5549 */
205 u8 add_path; /* Multiple paths support, RFC 7911 */
206 };
207
208 struct bgp_caps {
209 u32 as4_number; /* Announced ASN */
210
211 u8 as4_support; /* Four-octet AS capability, RFC 6793 */
212 u8 ext_messages; /* Extended message length, RFC draft */
213 u8 route_refresh; /* Route refresh capability, RFC 2918 */
214 u8 enhanced_refresh; /* Enhanced route refresh, RFC 7313 */
215
216 u8 gr_aware; /* Graceful restart capability, RFC 4724 */
217 u8 gr_flags; /* Graceful restart flags */
218 u16 gr_time; /* Graceful restart time in seconds */
219
220 u8 llgr_aware; /* Long-lived GR capability, RFC draft */
221
222 u16 af_count; /* Number of af_data items */
223 u16 length; /* Length of capabilities in OPEN msg */
224
225 struct bgp_af_caps af_data[0]; /* Per-AF capability data */
226 };
227
228 #define WALK_AF_CAPS(caps,ac) \
229 for (ac = caps->af_data; ac < &caps->af_data[caps->af_count]; ac++)
230
231
232 struct bgp_socket {
233 node n; /* Node in global bgp_sockets */
234 sock *sk; /* Real listening socket */
235 u32 uc; /* Use count */
236 };
237
238 struct bgp_conn {
239 struct bgp_proto *bgp;
240 struct birdsock *sk;
241 u8 state; /* State of connection state machine */
242 u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
243 u8 ext_messages; /* Session uses extended message length */
244 u32 received_as; /* ASN received in OPEN message */
245
246 struct bgp_caps *local_caps;
247 struct bgp_caps *remote_caps;
248 timer *connect_timer;
249 timer *hold_timer;
250 timer *keepalive_timer;
251 event *tx_ev;
252 u32 packets_to_send; /* Bitmap of packet types to be sent */
253 u32 channels_to_send; /* Bitmap of channels with packets to be sent */
254 u8 last_channel; /* Channel used last time for TX */
255 u8 last_channel_count; /* Number of times the last channel was used in succession */
256 int notify_code, notify_subcode, notify_size;
257 byte *notify_data;
258
259 uint hold_time, keepalive_time; /* Times calculated from my and neighbor's requirements */
260 };
261
262 struct bgp_proto {
263 struct proto p;
264 const struct bgp_config *cf; /* Shortcut to BGP configuration */
265 ip_addr local_ip, remote_ip;
266 u32 local_as, remote_as;
267 u32 public_as; /* Externally visible ASN (local_as or confederation id) */
268 u32 local_id; /* BGP identifier of this router */
269 u32 remote_id; /* BGP identifier of the neighbor */
270 u32 rr_cluster_id; /* Route reflector cluster ID */
271 int start_state; /* Substates that partitions BS_START */
272 u8 is_internal; /* Internal BGP session (local_as == remote_as) */
273 u8 is_interior; /* Internal or intra-confederation BGP session */
274 u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
275 u8 rr_client; /* Whether neighbor is RR client of me */
276 u8 rs_client; /* Whether neighbor is RS client of me */
277 u8 route_refresh; /* Route refresh allowed to send [RFC 2918] */
278 u8 enhanced_refresh; /* Enhanced refresh is negotiated [RFC 7313] */
279 u8 gr_ready; /* Neighbor could do graceful restart */
280 u8 llgr_ready; /* Neighbor could do Long-lived GR, implies gr_ready */
281 u8 gr_active_num; /* Neighbor is doing GR, number of active channels */
282 u8 channel_count; /* Number of active channels */
283 u8 summary_add_path_rx; /* Summary state of ADD_PATH RX w.r.t active channels */
284 u32 *afi_map; /* Map channel index -> AFI */
285 struct bgp_channel **channel_map; /* Map channel index -> channel */
286 struct bgp_conn *conn; /* Connection we have established */
287 struct bgp_conn outgoing_conn; /* Outgoing connection we're working with */
288 struct bgp_conn incoming_conn; /* Incoming connection we have neither accepted nor rejected yet */
289 struct object_lock *lock; /* Lock for neighbor connection */
290 struct neighbor *neigh; /* Neighbor entry corresponding to remote ip, NULL if multihop */
291 struct bgp_socket *sock; /* Shared listening socket */
292 struct bfd_request *bfd_req; /* BFD request, if BFD is used */
293 ip_addr link_addr; /* Link-local version of local_ip */
294 event *event; /* Event for respawning and shutting process */
295 timer *startup_timer; /* Timer used to delay protocol startup due to previous errors (startup_delay) */
296 timer *gr_timer; /* Timer waiting for reestablishment after graceful restart */
297 uint startup_delay; /* Delay (in seconds) of protocol startup due to previous errors */
298 btime last_proto_error; /* Time of last error that leads to protocol stop */
299 u8 last_error_class; /* Error class of last error */
300 u32 last_error_code; /* Error code of last error. BGP protocol errors
301 are encoded as (bgp_err_code << 16 | bgp_err_subcode) */
302 };
303
304 struct bgp_channel {
305 struct channel c;
306
307 /* Rest are BGP specific data */
308 struct bgp_channel_config *cf;
309
310 u32 afi;
311 u32 index;
312 const struct bgp_af_desc *desc;
313
314 rtable *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
315 rtable *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
316
317 /* Rest are zeroed when down */
318 pool *pool;
319 HASH(struct bgp_bucket) bucket_hash; /* Hash table of route buckets */
320 struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */
321 list bucket_queue; /* Queue of buckets to send (struct bgp_bucket) */
322
323 HASH(struct bgp_prefix) prefix_hash; /* Prefixes to be sent */
324 slab *prefix_slab; /* Slab holding prefix nodes */
325
326 ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
327 ip_addr link_addr; /* Link-local version of next_hop_addr */
328
329 u32 packets_to_send; /* Bitmap of packet types to be sent */
330
331 u8 ext_next_hop; /* Session allows both IPv4 and IPv6 next hops */
332
333 u8 gr_ready; /* Neighbor could do GR on this AF */
334 u8 gr_active; /* Neighbor is doing GR (BGP_GRS_*) */
335
336 timer *stale_timer; /* Long-lived stale timer for LLGR */
337 u32 stale_time; /* Stored LLGR stale time from last session */
338
339 u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */
340 u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */
341
342 u8 feed_state; /* Feed state (TX) for EoR, RR packets, see BFS_* */
343 u8 load_state; /* Load state (RX) for EoR, RR packets, see BFS_* */
344 };
345
346 struct bgp_prefix {
347 node buck_node; /* Node in per-bucket list */
348 struct bgp_prefix *next; /* Node in prefix hash table */
349 u32 hash;
350 u32 path_id;
351 net_addr net[0];
352 };
353
354 struct bgp_bucket {
355 node send_node; /* Node in send queue */
356 struct bgp_bucket *next; /* Node in bucket hash table */
357 list prefixes; /* Prefixes in this bucket (struct bgp_prefix) */
358 u32 hash; /* Hash over extended attributes */
359 ea_list eattrs[0]; /* Per-bucket extended attributes */
360 };
361
362 struct bgp_export_state {
363 struct bgp_proto *proto;
364 struct bgp_channel *channel;
365 struct linpool *pool;
366
367 struct bgp_proto *src;
368 rte *route;
369 int mpls;
370
371 u32 attrs_seen[1];
372 uint err_withdraw;
373 };
374
375 struct bgp_write_state {
376 struct bgp_proto *proto;
377 struct bgp_channel *channel;
378 struct linpool *pool;
379
380 int mp_reach;
381 int as4_session;
382 int add_path;
383 int mpls;
384
385 eattr *mp_next_hop;
386 adata *mpls_labels;
387 };
388
389 struct bgp_parse_state {
390 struct bgp_proto *proto;
391 struct bgp_channel *channel;
392 struct linpool *pool;
393
394 int as4_session;
395 int add_path;
396 int mpls;
397
398 u32 attrs_seen[256/32];
399
400 u32 mp_reach_af;
401 u32 mp_unreach_af;
402
403 uint attr_len;
404 uint ip_reach_len;
405 uint ip_unreach_len;
406 uint ip_next_hop_len;
407 uint mp_reach_len;
408 uint mp_unreach_len;
409 uint mp_next_hop_len;
410
411 byte *attrs;
412 byte *ip_reach_nlri;
413 byte *ip_unreach_nlri;
414 byte *ip_next_hop_data;
415 byte *mp_reach_nlri;
416 byte *mp_unreach_nlri;
417 byte *mp_next_hop_data;
418
419 uint err_withdraw;
420 uint err_subcode;
421 jmp_buf err_jmpbuf;
422
423 struct hostentry *hostentry;
424 adata *mpls_labels;
425
426 /* Cached state for bgp_rte_update() */
427 u32 last_id;
428 struct rte_src *last_src;
429 rta *cached_rta;
430 };
431
432 #define BGP_PORT 179
433 #define BGP_VERSION 4
434 #define BGP_HEADER_LENGTH 19
435 #define BGP_MAX_MESSAGE_LENGTH 4096
436 #define BGP_MAX_EXT_MSG_LENGTH 65535
437 #define BGP_RX_BUFFER_SIZE 4096
438 #define BGP_TX_BUFFER_SIZE 4096
439 #define BGP_RX_BUFFER_EXT_SIZE 65535
440 #define BGP_TX_BUFFER_EXT_SIZE 65535
441
442 static inline int bgp_channel_is_ipv4(struct bgp_channel *c)
443 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
444
445 static inline int bgp_channel_is_ipv6(struct bgp_channel *c)
446 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
447
448 static inline int bgp_cc_is_ipv4(struct bgp_channel_config *c)
449 { return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
450
451 static inline int bgp_cc_is_ipv6(struct bgp_channel_config *c)
452 { return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
453
454 static inline uint bgp_max_packet_length(struct bgp_conn *conn)
455 { return conn->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
456
457 static inline void
458 bgp_parse_error(struct bgp_parse_state *s, uint subcode)
459 {
460 s->err_subcode = subcode;
461 longjmp(s->err_jmpbuf, 1);
462 }
463
464 extern struct linpool *bgp_linpool;
465 extern struct linpool *bgp_linpool2;
466
467
468 void bgp_start_timer(timer *t, uint value);
469 void bgp_check_config(struct bgp_config *c);
470 void bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int len);
471 void bgp_close_conn(struct bgp_conn *c);
472 void bgp_update_startup_delay(struct bgp_proto *p);
473 void bgp_conn_enter_openconfirm_state(struct bgp_conn *conn);
474 void bgp_conn_enter_established_state(struct bgp_conn *conn);
475 void bgp_conn_enter_close_state(struct bgp_conn *conn);
476 void bgp_conn_enter_idle_state(struct bgp_conn *conn);
477 void bgp_handle_graceful_restart(struct bgp_proto *p);
478 void bgp_graceful_restart_done(struct bgp_channel *c);
479 void bgp_refresh_begin(struct bgp_channel *c);
480 void bgp_refresh_end(struct bgp_channel *c);
481 void bgp_store_error(struct bgp_proto *p, struct bgp_conn *c, u8 class, u32 code);
482 void bgp_stop(struct bgp_proto *p, uint subcode, byte *data, uint len);
483
484 struct rte_source *bgp_find_source(struct bgp_proto *p, u32 path_id);
485 struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
486
487
488
489 #ifdef LOCAL_DEBUG
490 #define BGP_FORCE_DEBUG 1
491 #else
492 #define BGP_FORCE_DEBUG 0
493 #endif
494 #define BGP_TRACE(flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
495 log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
496
497 #define BGP_TRACE_RL(rl, flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
498 log_rl(rl, L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
499
500
501 /* attrs.c */
502
503 static inline eattr *
504 bgp_find_attr(ea_list *attrs, uint code)
505 {
506 return ea_find(attrs, EA_CODE(PROTOCOL_BGP, code));
507 }
508
509 eattr *
510 bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val);
511
512 static inline void
513 bgp_set_attr_u32(ea_list **to, struct linpool *pool, uint code, uint flags, u32 val)
514 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
515
516 static inline void
517 bgp_set_attr_ptr(ea_list **to, struct linpool *pool, uint code, uint flags, struct adata *val)
518 { bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
519
520 static inline void
521 bgp_set_attr_data(ea_list **to, struct linpool *pool, uint code, uint flags, void *data, uint len)
522 {
523 struct adata *a = lp_alloc_adata(pool, len);
524 memcpy(a->data, data, len);
525 bgp_set_attr(to, pool, code, flags, (uintptr_t) a);
526 }
527
528 static inline void
529 bgp_unset_attr(ea_list **to, struct linpool *pool, uint code)
530 { eattr *e = bgp_set_attr(to, pool, code, 0, 0); e->type = EAF_TYPE_UNDEF; }
531
532
533 int bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end);
534 ea_list * bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len);
535
536 void bgp_init_bucket_table(struct bgp_channel *c);
537 void bgp_free_bucket_table(struct bgp_channel *c);
538 void bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b);
539 void bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b);
540 void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
541
542 void bgp_init_prefix_table(struct bgp_channel *c);
543 void bgp_free_prefix_table(struct bgp_channel *c);
544 void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
545
546 int bgp_rte_better(struct rte *, struct rte *);
547 int bgp_rte_mergable(rte *pri, rte *sec);
548 int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
549 struct rte *bgp_rte_modify_stale(struct rte *r, struct linpool *pool);
550 void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old);
551 int bgp_preexport(struct proto *, struct rte **, struct linpool *);
552 int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
553 void bgp_get_route_info(struct rte *, byte *buf);
554
555
556 /* packets.c */
557
558 void bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new);
559 const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
560 const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
561 void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
562 void bgp_kick_tx(void *vconn);
563 void bgp_tx(struct birdsock *sk);
564 int bgp_rx(struct birdsock *sk, uint size);
565 const char * bgp_error_dsc(unsigned code, unsigned subcode);
566 void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
567
568 void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
569
570
571 /* Packet types */
572
573 #define PKT_OPEN 0x01
574 #define PKT_UPDATE 0x02
575 #define PKT_NOTIFICATION 0x03
576 #define PKT_KEEPALIVE 0x04
577 #define PKT_ROUTE_REFRESH 0x05 /* [RFC2918] */
578 #define PKT_BEGIN_REFRESH 0x1e /* Dummy type for BoRR packet [RFC7313] */
579 #define PKT_SCHEDULE_CLOSE 0x1f /* Used internally to schedule socket close */
580
581 /* Attributes */
582
583 #define BAF_OPTIONAL 0x80
584 #define BAF_TRANSITIVE 0x40
585 #define BAF_PARTIAL 0x20
586 #define BAF_EXT_LEN 0x10
587
588 #define BA_ORIGIN 0x01 /* RFC 4271 */ /* WM */
589 #define BA_AS_PATH 0x02 /* WM */
590 #define BA_NEXT_HOP 0x03 /* WM */
591 #define BA_MULTI_EXIT_DISC 0x04 /* ON */
592 #define BA_LOCAL_PREF 0x05 /* WD */
593 #define BA_ATOMIC_AGGR 0x06 /* WD */
594 #define BA_AGGREGATOR 0x07 /* OT */
595 #define BA_COMMUNITY 0x08 /* RFC 1997 */ /* OT */
596 #define BA_ORIGINATOR_ID 0x09 /* RFC 4456 */ /* ON */
597 #define BA_CLUSTER_LIST 0x0a /* RFC 4456 */ /* ON */
598 #define BA_MP_REACH_NLRI 0x0e /* RFC 4760 */
599 #define BA_MP_UNREACH_NLRI 0x0f /* RFC 4760 */
600 #define BA_EXT_COMMUNITY 0x10 /* RFC 4360 */
601 #define BA_AS4_PATH 0x11 /* RFC 6793 */
602 #define BA_AS4_AGGREGATOR 0x12 /* RFC 6793 */
603 #define BA_LARGE_COMMUNITY 0x20 /* RFC 8092 */
604
605 /* Bird's private internal BGP attributes */
606 #define BA_MPLS_LABEL_STACK 0xfe /* MPLS label stack transfer attribute */
607
608 /* BGP connection states */
609
610 #define BS_IDLE 0
611 #define BS_CONNECT 1 /* Attempting to connect */
612 #define BS_ACTIVE 2 /* Waiting for connection retry & listening */
613 #define BS_OPENSENT 3
614 #define BS_OPENCONFIRM 4
615 #define BS_ESTABLISHED 5
616 #define BS_CLOSE 6 /* Used during transition to BS_IDLE */
617
618 #define BS_MAX 7
619
620 /* BGP start states
621 *
622 * Used in PS_START for fine-grained specification of starting state.
623 *
624 * When BGP protocol is started by core, it goes to BSS_PREPARE. When BGP
625 * protocol done what is neccessary to start itself (like acquiring the lock),
626 * it goes to BSS_CONNECT.
627 */
628
629 #define BSS_PREPARE 0 /* Used before ordinary BGP started, i. e. waiting for lock */
630 #define BSS_DELAY 1 /* Startup delay due to previous errors */
631 #define BSS_CONNECT 2 /* Ordinary BGP connecting */
632
633
634 /* BGP feed states (TX)
635 *
636 * RFC 4724 specifies that an initial feed should end with End-of-RIB mark.
637 *
638 * RFC 7313 specifies that a route refresh should be demarcated by BoRR and EoRR packets.
639 *
640 * These states (stored in c->feed_state) are used to keep track of these
641 * requirements. When such feed is started, BFS_LOADING / BFS_REFRESHING is
642 * set. When it ended, BFS_LOADED / BFS_REFRESHED is set to schedule End-of-RIB
643 * or EoRR packet. When the packet is sent, the state returned to BFS_NONE.
644 *
645 * Note that when a non-demarcated feed (e.g. plain RFC 4271 initial load
646 * without End-of-RIB or plain RFC 2918 route refresh without BoRR/EoRR
647 * demarcation) is active, BFS_NONE is set.
648 *
649 * BFS_NONE, BFS_LOADING and BFS_REFRESHING are also used as load states (RX)
650 * with correspondent semantics (-, expecting End-of-RIB, expecting EoRR).
651 */
652
653 #define BFS_NONE 0 /* No feed or original non-demarcated feed */
654 #define BFS_LOADING 1 /* Initial feed active, End-of-RIB planned */
655 #define BFS_LOADED 2 /* Loading done, End-of-RIB marker scheduled */
656 #define BFS_REFRESHING 3 /* Route refresh (introduced by BoRR) active */
657 #define BFS_REFRESHED 4 /* Refresh done, EoRR packet scheduled */
658
659
660 /* Error classes */
661
662 #define BE_NONE 0
663 #define BE_MISC 1 /* Miscellaneous error */
664 #define BE_SOCKET 2 /* Socket error */
665 #define BE_BGP_RX 3 /* BGP protocol error notification received */
666 #define BE_BGP_TX 4 /* BGP protocol error notification sent */
667 #define BE_AUTO_DOWN 5 /* Automatic shutdown */
668 #define BE_MAN_DOWN 6 /* Manual shutdown */
669
670 /* Misc error codes */
671
672 #define BEM_NEIGHBOR_LOST 1
673 #define BEM_INVALID_NEXT_HOP 2
674 #define BEM_INVALID_MD5 3 /* MD5 authentication kernel request failed (possibly not supported) */
675 #define BEM_NO_SOCKET 4
676 #define BEM_LINK_DOWN 5
677 #define BEM_BFD_DOWN 6
678 #define BEM_GRACEFUL_RESTART 7
679
680 /* Automatic shutdown error codes */
681
682 #define BEA_ROUTE_LIMIT_EXCEEDED 1
683
684 /* Well-known communities */
685
686 #define BGP_COMM_NO_EXPORT 0xffffff01 /* Don't export outside local AS / confed. */
687 #define BGP_COMM_NO_ADVERTISE 0xffffff02 /* Don't export at all */
688 #define BGP_COMM_NO_EXPORT_SUBCONFED 0xffffff03 /* NO_EXPORT even in local confederation */
689
690 #define BGP_COMM_LLGR_STALE 0xffff0006 /* Route is stale according to LLGR */
691 #define BGP_COMM_NO_LLGR 0xffff0007 /* Do not treat the route according to LLGR */
692
693 /* Origins */
694
695 #define ORIGIN_IGP 0
696 #define ORIGIN_EGP 1
697 #define ORIGIN_INCOMPLETE 2
698
699
700 #endif