bird/proto/bgp/bgp.h

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/*
* BIRD -- The Border Gateway Protocol
*
* (c) 2000 Martin Mares <mj@ucw.cz>
* (c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
* (c) 2008--2016 CZ.NIC z.s.p.o.
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*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_BGP_H_
#define _BIRD_BGP_H_
#include <stdint.h>
#include <setjmp.h>
#include "nest/bird.h"
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#include "nest/route.h"
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#include "nest/bfd.h"
//#include "lib/lists.h"
#include "lib/hash.h"
#include "lib/socket.h"
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struct linpool;
struct eattr;
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/* Address families */
#define BGP_AFI_IPV4 1
#define BGP_AFI_IPV6 2
#define BGP_SAFI_UNICAST 1
#define BGP_SAFI_MULTICAST 2
#define BGP_SAFI_MPLS 4
#define BGP_SAFI_MPLS_VPN 128
#define BGP_SAFI_VPN_MULTICAST 129
#define BGP_SAFI_FLOW 133
/* Internal AF codes */
#define BGP_AF(A, B) (((u32)(A) << 16) | (u32)(B))
#define BGP_AFI(A) ((u32)(A) >> 16)
#define BGP_SAFI(A) ((u32)(A) & 0xFFFF)
#define BGP_AF_IPV4 BGP_AF( BGP_AFI_IPV4, BGP_SAFI_UNICAST )
#define BGP_AF_IPV6 BGP_AF( BGP_AFI_IPV6, BGP_SAFI_UNICAST )
#define BGP_AF_IPV4_MC BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MULTICAST )
#define BGP_AF_IPV6_MC BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MULTICAST )
#define BGP_AF_IPV4_MPLS BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS )
#define BGP_AF_IPV6_MPLS BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS )
#define BGP_AF_VPN4_MPLS BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MPLS_VPN )
#define BGP_AF_VPN6_MPLS BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MPLS_VPN )
#define BGP_AF_VPN4_MC BGP_AF( BGP_AFI_IPV4, BGP_SAFI_VPN_MULTICAST )
#define BGP_AF_VPN6_MC BGP_AF( BGP_AFI_IPV6, BGP_SAFI_VPN_MULTICAST )
#define BGP_AF_FLOW4 BGP_AF( BGP_AFI_IPV4, BGP_SAFI_FLOW )
#define BGP_AF_FLOW6 BGP_AF( BGP_AFI_IPV6, BGP_SAFI_FLOW )
struct bgp_write_state;
struct bgp_parse_state;
struct bgp_export_state;
struct bgp_bucket;
struct bgp_af_desc {
u32 afi;
u32 net;
u8 mpls;
u8 no_igp;
const char *name;
uint (*encode_nlri)(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size);
void (*decode_nlri)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
void (*update_next_hop)(struct bgp_export_state *s, eattr *nh, ea_list **to);
uint (*encode_next_hop)(struct bgp_write_state *s, eattr *nh, byte *buf, uint size);
void (*decode_next_hop)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
};
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struct bgp_config {
struct proto_config c;
u32 local_as, remote_as;
ip_addr local_ip; /* Source address to use */
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ip_addr remote_ip;
struct iface *iface; /* Interface for link-local addresses */
u16 local_port; /* Local listening port */
u16 remote_port; /* Neighbor destination port */
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int multihop; /* Number of hops if multihop */
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int strict_bind; /* Bind listening socket to local address */
int ttl_security; /* Enable TTL security [RFC 5082] */
int compare_path_lengths; /* Use path lengths when selecting best route */
int med_metric; /* Compare MULTI_EXIT_DISC even between routes from differen ASes */
int igp_metric; /* Use IGP metrics when selecting best route */
int prefer_older; /* Prefer older routes according to RFC 5004 */
int deterministic_med; /* Use more complicated algo to have strict RFC 4271 MED comparison */
u32 default_local_pref; /* Default value for LOCAL_PREF attribute */
u32 default_med; /* Default value for MULTI_EXIT_DISC attribute */
int capabilities; /* Enable capability handshake [RFC 5492] */
int enable_refresh; /* Enable local support for route refresh [RFC 2918] */
int enable_as4; /* Enable local support for 4B AS numbers [RFC 6793] */
int enable_extended_messages; /* Enable local support for extended messages [draft] */
u32 rr_cluster_id; /* Route reflector cluster ID, if different from local ID */
int rr_client; /* Whether neighbor is RR client of me */
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int rs_client; /* Whether neighbor is RS client of me */
u32 confederation; /* Confederation ID, or zero if confeds not active */
int confederation_member; /* Whether neighbor AS is member of our confederation */
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int passive; /* Do not initiate outgoing connection */
int interpret_communities; /* Hardwired handling of well-known communities */
int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */
int allow_local_pref; /* Allow LOCAL_PREF in EBGP sessions */
int gr_mode; /* Graceful restart mode (BGP_GR_*) */
int llgr_mode; /* Long-lived graceful restart mode (BGP_LLGR_*) */
int setkey; /* Set MD5 password to system SA/SP database */
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/* Times below are in seconds */
unsigned gr_time; /* Graceful restart timeout */
unsigned llgr_time; /* Long-lived graceful restart stale time */
unsigned connect_delay_time; /* Minimum delay between connect attempts */
unsigned connect_retry_time; /* Timeout for connect attempts */
unsigned hold_time, initial_hold_time;
unsigned keepalive_time;
unsigned error_amnesia_time; /* Errors are forgotten after */
unsigned error_delay_time_min; /* Time to wait after an error is detected */
unsigned error_delay_time_max;
unsigned disable_after_error; /* Disable the protocol when error is detected */
u32 disable_after_cease; /* Disable it when cease is received, bitfield */
char *password; /* Password used for MD5 authentication */
int check_link; /* Use iface link state for liveness detection */
int bfd; /* Use BFD for liveness detection */
};
struct bgp_channel_config {
struct channel_config c;
u32 afi;
const struct bgp_af_desc *desc;
ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
u8 next_hop_self; /* Always set next hop to local IP address (NH_*) */
u8 next_hop_keep; /* Do not modify next hop attribute (NH_*) */
u8 missing_lladdr; /* What we will do when we don' know link-local addr, see MLL_* */
u8 gw_mode; /* How we compute route gateway from next_hop attr, see GW_* */
u8 secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */
u8 gr_able; /* Allow full graceful restart for the channel */
u8 llgr_able; /* Allow full long-lived GR for the channel */
uint llgr_time; /* Long-lived graceful restart stale time */
u8 ext_next_hop; /* Allow both IPv4 and IPv6 next hops */
u8 add_path; /* Use ADD-PATH extension [RFC 7911] */
u8 import_table; /* Use c.in_table as Adj-RIB-In */
uint rest[0]; /* Remaining items are reconfigured separately */
struct rtable_config *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
struct rtable_config *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
};
#define NH_NO 0
#define NH_ALL 1
#define NH_IBGP 2
#define NH_EBGP 3
#define MLL_SELF 1
#define MLL_DROP 2
#define MLL_IGNORE 3
#define GW_DIRECT 1
#define GW_RECURSIVE 2
#define BGP_ADD_PATH_RX 1
#define BGP_ADD_PATH_TX 2
#define BGP_ADD_PATH_FULL 3
#define BGP_GR_ABLE 1
#define BGP_GR_AWARE 2
/* For GR capability common flags */
#define BGP_GRF_RESTART 0x80
/* For GR capability per-AF flags */
#define BGP_GRF_FORWARDING 0x80
#define BGP_LLGR_ABLE 1
#define BGP_LLGR_AWARE 2
#define BGP_LLGRF_FORWARDING 0x80
#define BGP_GRS_NONE 0 /* No GR */
#define BGP_GRS_ACTIVE 1 /* Graceful restart per RFC 4724 */
#define BGP_GRS_LLGR 2 /* Long-lived GR phase (stale timer active) */
#define BGP_BFD_GRACEFUL 2 /* BFD down triggers graceful restart */
struct bgp_af_caps {
u32 afi;
u8 ready; /* Multiprotocol capability, RFC 4760 */
u8 gr_able; /* Graceful restart support, RFC 4724 */
u8 gr_af_flags; /* Graceful restart per-AF flags */
u8 llgr_able; /* Long-lived GR, RFC draft */
u32 llgr_time; /* Long-lived GR stale time */
u8 llgr_flags; /* Long-lived GR per-AF flags */
u8 ext_next_hop; /* Extended IPv6 next hop, RFC 5549 */
u8 add_path; /* Multiple paths support, RFC 7911 */
};
struct bgp_caps {
u32 as4_number; /* Announced ASN */
u8 as4_support; /* Four-octet AS capability, RFC 6793 */
u8 ext_messages; /* Extended message length, RFC draft */
u8 route_refresh; /* Route refresh capability, RFC 2918 */
u8 enhanced_refresh; /* Enhanced route refresh, RFC 7313 */
u8 gr_aware; /* Graceful restart capability, RFC 4724 */
u8 gr_flags; /* Graceful restart flags */
u16 gr_time; /* Graceful restart time in seconds */
u8 llgr_aware; /* Long-lived GR capability, RFC draft */
u16 af_count; /* Number of af_data items */
struct bgp_af_caps af_data[0]; /* Per-AF capability data */
};
#define WALK_AF_CAPS(caps,ac) \
for (ac = caps->af_data; ac < &caps->af_data[caps->af_count]; ac++)
struct bgp_socket {
node n; /* Node in global bgp_sockets */
sock *sk; /* Real listening socket */
u32 uc; /* Use count */
};
struct bgp_conn {
struct bgp_proto *bgp;
struct birdsock *sk;
u8 state; /* State of connection state machine */
u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
u8 ext_messages; /* Session uses extended message length */
struct bgp_caps *local_caps;
struct bgp_caps *remote_caps;
timer *connect_timer;
timer *hold_timer;
timer *keepalive_timer;
event *tx_ev;
u32 packets_to_send; /* Bitmap of packet types to be sent */
u32 channels_to_send; /* Bitmap of channels with packets to be sent */
u8 last_channel; /* Channel used last time for TX */
u8 last_channel_count; /* Number of times the last channel was used in succession */
int notify_code, notify_subcode, notify_size;
byte *notify_data;
uint hold_time, keepalive_time; /* Times calculated from my and neighbor's requirements */
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};
struct bgp_proto {
struct proto p;
struct bgp_config *cf; /* Shortcut to BGP configuration */
u32 local_as, remote_as;
u32 public_as; /* Externally visible ASN (local_as or confederation id) */
u32 local_id; /* BGP identifier of this router */
u32 remote_id; /* BGP identifier of the neighbor */
u32 rr_cluster_id; /* Route reflector cluster ID */
int start_state; /* Substates that partitions BS_START */
u8 is_internal; /* Internal BGP session (local_as == remote_as) */
u8 is_interior; /* Internal or intra-confederation BGP session */
u8 as4_session; /* Session uses 4B AS numbers in AS_PATH (both sides support it) */
u8 rr_client; /* Whether neighbor is RR client of me */
u8 rs_client; /* Whether neighbor is RS client of me */
u8 route_refresh; /* Route refresh allowed to send [RFC 2918] */
u8 enhanced_refresh; /* Enhanced refresh is negotiated [RFC 7313] */
u8 gr_ready; /* Neighbor could do graceful restart */
u8 llgr_ready; /* Neighbor could do Long-lived GR, implies gr_ready */
u8 gr_active_num; /* Neighbor is doing GR, number of active channels */
u8 channel_count; /* Number of active channels */
u8 summary_add_path_rx; /* Summary state of ADD_PATH RX w.r.t active channels */
u32 *afi_map; /* Map channel index -> AFI */
struct bgp_channel **channel_map; /* Map channel index -> channel */
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struct bgp_conn *conn; /* Connection we have established */
struct bgp_conn outgoing_conn; /* Outgoing connection we're working with */
struct bgp_conn incoming_conn; /* Incoming connection we have neither accepted nor rejected yet */
struct object_lock *lock; /* Lock for neighbor connection */
struct neighbor *neigh; /* Neighbor entry corresponding to remote ip, NULL if multihop */
struct bgp_socket *sock; /* Shared listening socket */
struct bfd_request *bfd_req; /* BFD request, if BFD is used */
ip_addr source_addr; /* Local address used as an advertised next hop */
ip_addr link_addr; /* Link-local version of source_addr */
event *event; /* Event for respawning and shutting process */
timer *startup_timer; /* Timer used to delay protocol startup due to previous errors (startup_delay) */
timer *gr_timer; /* Timer waiting for reestablishment after graceful restart */
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uint startup_delay; /* Delay (in seconds) of protocol startup due to previous errors */
btime last_proto_error; /* Time of last error that leads to protocol stop */
u8 last_error_class; /* Error class of last error */
u32 last_error_code; /* Error code of last error. BGP protocol errors
are encoded as (bgp_err_code << 16 | bgp_err_subcode) */
};
struct bgp_channel {
struct channel c;
/* Rest are BGP specific data */
struct bgp_channel_config *cf;
u32 afi;
u32 index;
const struct bgp_af_desc *desc;
rtable *igp_table_ip4; /* Table for recursive IPv4 next hop lookups */
rtable *igp_table_ip6; /* Table for recursive IPv6 next hop lookups */
/* Rest are zeroed when down */
pool *pool;
HASH(struct bgp_bucket) bucket_hash; /* Hash table of route buckets */
struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */
list bucket_queue; /* Queue of buckets to send (struct bgp_bucket) */
HASH(struct bgp_prefix) prefix_hash; /* Prefixes to be sent */
slab *prefix_slab; /* Slab holding prefix nodes */
ip_addr next_hop_addr; /* Local address for NEXT_HOP attribute */
ip_addr link_addr; /* Link-local version of next_hop_addr */
u32 packets_to_send; /* Bitmap of packet types to be sent */
u8 ext_next_hop; /* Session allows both IPv4 and IPv6 next hops */
u8 gr_ready; /* Neighbor could do GR on this AF */
u8 gr_active; /* Neighbor is doing GR (BGP_GRS_*) */
timer *stale_timer; /* Long-lived stale timer for LLGR */
u32 stale_time; /* Stored LLGR stale time from last session */
u8 add_path_rx; /* Session expects receive of ADD-PATH extended NLRI */
u8 add_path_tx; /* Session expects transmit of ADD-PATH extended NLRI */
u8 feed_state; /* Feed state (TX) for EoR, RR packets, see BFS_* */
u8 load_state; /* Load state (RX) for EoR, RR packets, see BFS_* */
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};
struct bgp_prefix {
node buck_node; /* Node in per-bucket list */
struct bgp_prefix *next; /* Node in prefix hash table */
u32 hash;
u32 path_id;
net_addr net[0];
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};
struct bgp_bucket {
node send_node; /* Node in send queue */
struct bgp_bucket *next; /* Node in bucket hash table */
list prefixes; /* Prefixes in this bucket (struct bgp_prefix) */
u32 hash; /* Hash over extended attributes */
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ea_list eattrs[0]; /* Per-bucket extended attributes */
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};
struct bgp_export_state {
struct bgp_proto *proto;
struct bgp_channel *channel;
struct linpool *pool;
struct bgp_proto *src;
rte *route;
int mpls;
u32 attrs_seen[1];
uint err_withdraw;
};
struct bgp_write_state {
struct bgp_proto *proto;
struct bgp_channel *channel;
struct linpool *pool;
int mp_reach;
int as4_session;
int add_path;
int mpls;
eattr *mp_next_hop;
const adata *mpls_labels;
};
struct bgp_parse_state {
struct bgp_proto *proto;
struct bgp_channel *channel;
struct linpool *pool;
int as4_session;
int add_path;
int mpls;
u32 attrs_seen[256/32];
u32 mp_reach_af;
u32 mp_unreach_af;
uint attr_len;
uint ip_reach_len;
uint ip_unreach_len;
uint ip_next_hop_len;
uint mp_reach_len;
uint mp_unreach_len;
uint mp_next_hop_len;
byte *attrs;
byte *ip_reach_nlri;
byte *ip_unreach_nlri;
byte *ip_next_hop_data;
byte *mp_reach_nlri;
byte *mp_unreach_nlri;
byte *mp_next_hop_data;
uint err_withdraw;
uint err_subcode;
jmp_buf err_jmpbuf;
struct hostentry *hostentry;
adata *mpls_labels;
/* Cached state for bgp_rte_update() */
u32 last_id;
struct rte_src *last_src;
rta *cached_rta;
};
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#define BGP_PORT 179
#define BGP_VERSION 4
#define BGP_HEADER_LENGTH 19
#define BGP_MAX_MESSAGE_LENGTH 4096
#define BGP_MAX_EXT_MSG_LENGTH 65535
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#define BGP_RX_BUFFER_SIZE 4096
#define BGP_TX_BUFFER_SIZE 4096
#define BGP_RX_BUFFER_EXT_SIZE 65535
#define BGP_TX_BUFFER_EXT_SIZE 65535
static inline int bgp_channel_is_ipv4(struct bgp_channel *c)
{ return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
static inline int bgp_channel_is_ipv6(struct bgp_channel *c)
{ return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
static inline int bgp_cc_is_ipv4(struct bgp_channel_config *c)
{ return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
static inline int bgp_cc_is_ipv6(struct bgp_channel_config *c)
{ return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
static inline uint bgp_max_packet_length(struct bgp_conn *conn)
{ return conn->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
static inline void
bgp_parse_error(struct bgp_parse_state *s, uint subcode)
{
s->err_subcode = subcode;
longjmp(s->err_jmpbuf, 1);
}
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extern struct linpool *bgp_linpool;
extern struct linpool *bgp_linpool2;
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void bgp_start_timer(timer *t, uint value);
void bgp_check_config(struct bgp_config *c);
void bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int len);
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void bgp_close_conn(struct bgp_conn *c);
void bgp_update_startup_delay(struct bgp_proto *p);
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void bgp_conn_enter_openconfirm_state(struct bgp_conn *conn);
void bgp_conn_enter_established_state(struct bgp_conn *conn);
void bgp_conn_enter_close_state(struct bgp_conn *conn);
void bgp_conn_enter_idle_state(struct bgp_conn *conn);
void bgp_handle_graceful_restart(struct bgp_proto *p);
void bgp_graceful_restart_done(struct bgp_channel *c);
void bgp_refresh_begin(struct bgp_channel *c);
void bgp_refresh_end(struct bgp_channel *c);
void bgp_store_error(struct bgp_proto *p, struct bgp_conn *c, u8 class, u32 code);
void bgp_stop(struct bgp_proto *p, uint subcode, byte *data, uint len);
struct rte_source *bgp_find_source(struct bgp_proto *p, u32 path_id);
struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
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#ifdef LOCAL_DEBUG
#define BGP_FORCE_DEBUG 1
#else
#define BGP_FORCE_DEBUG 0
#endif
#define BGP_TRACE(flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
#define BGP_TRACE_RL(rl, flags, msg, args...) do { if ((p->p.debug & flags) || BGP_FORCE_DEBUG) \
log_rl(rl, L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
/* attrs.c */
static inline eattr *
bgp_find_attr(ea_list *attrs, uint code)
{
return ea_find(attrs, EA_CODE(PROTOCOL_BGP, code));
}
eattr *
bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val);
static inline void
bgp_set_attr_u32(ea_list **to, struct linpool *pool, uint code, uint flags, u32 val)
{ bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
static inline void
bgp_set_attr_ptr(ea_list **to, struct linpool *pool, uint code, uint flags, const struct adata *val)
{ bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
static inline void
bgp_set_attr_data(ea_list **to, struct linpool *pool, uint code, uint flags, void *data, uint len)
{
struct adata *a = lp_alloc_adata(pool, len);
memcpy(a->data, data, len);
bgp_set_attr(to, pool, code, flags, (uintptr_t) a);
}
static inline void
bgp_unset_attr(ea_list **to, struct linpool *pool, uint code)
{ eattr *e = bgp_set_attr(to, pool, code, 0, 0); e->type = EAF_TYPE_UNDEF; }
int bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end);
ea_list * bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len);
void bgp_init_bucket_table(struct bgp_channel *c);
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void bgp_free_bucket_table(struct bgp_channel *c);
void bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b);
void bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b);
void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
void bgp_init_prefix_table(struct bgp_channel *c);
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void bgp_free_prefix_table(struct bgp_channel *c);
void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
int bgp_rte_better(struct rte *, struct rte *);
int bgp_rte_mergable(rte *pri, rte *sec);
int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
struct rte *bgp_rte_modify_stale(struct rte *r, struct linpool *pool);
void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old);
Terminology cleanup: The import_control hook is now called preexport. Once upon a time, far far away, there were the old Bird developers discussing what direction of route flow shall be called import and export. They decided to say "import to protocol" and "export to table" when speaking about a protocol. When speaking about a table, they spoke about "importing to table" and "exporting to protocol". The latter terminology was adopted in configuration, then also the bird CLI in commit ea2ae6dd0 started to use it (in year 2009). Now it's 2018 and the terminology is the latter. Import is from protocol to table, export is from table to protocol. Anyway, there was still an import_control hook which executed right before route export. One thing is funny. There are two commits in April 1999 with just two minutes between them. The older announces the final settlement on config terminology, the newer uses the other definition. Let's see their commit messages as the git-log tool shows them (the newer first): commit 9e0e485e50ea74c4f1c5cb65bdfe6ce819c2cee2 Author: Martin Mares <mj@ucw.cz> Date: Mon Apr 5 20:17:59 1999 +0000 Added some new protocol hooks (look at the comments for better explanation): make_tmp_attrs Convert inline attributes to ea_list store_tmp_attrs Convert ea_list to inline attributes import_control Pre-import decisions commit 5056c559c4eb253a4eee10cf35b694faec5265eb Author: Martin Mares <mj@ucw.cz> Date: Mon Apr 5 20:15:31 1999 +0000 Changed syntax of attaching filters to protocols to hopefully the final version: EXPORT <filter-spec> for outbound routes (i.e., those announced by BIRD to the rest of the world). IMPORT <filter-spec> for inbound routes (i.e., those imported by BIRD from the rest of the world). where <filter-spec> is one of: ALL pass all routes NONE drop all routes FILTER <name> use named filter FILTER { <filter> } use explicitly defined filter For all protocols, the default is IMPORT ALL, EXPORT NONE. This includes the kernel protocol, so that you need to add EXPORT ALL to get the previous configuration of kernel syncer (as usually, see doc/bird.conf.example for a bird.conf example :)). Let's say RIP to this almost 19-years-old inconsistency. For now, if you import a route, it is always from protocol to table. If you export a route, it is always from table to protocol. And they lived happily ever after.
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int bgp_preexport(struct proto *, struct rte **, struct linpool *);
int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
void bgp_get_route_info(struct rte *, byte *buf);
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/* packets.c */
void bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new);
const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
void bgp_kick_tx(void *vconn);
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void bgp_tx(struct birdsock *sk);
int bgp_rx(struct birdsock *sk, uint size);
const char * bgp_error_dsc(unsigned code, unsigned subcode);
void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
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void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
/* Packet types */
#define PKT_OPEN 0x01
#define PKT_UPDATE 0x02
#define PKT_NOTIFICATION 0x03
#define PKT_KEEPALIVE 0x04
#define PKT_ROUTE_REFRESH 0x05 /* [RFC2918] */
#define PKT_BEGIN_REFRESH 0x1e /* Dummy type for BoRR packet [RFC7313] */
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#define PKT_SCHEDULE_CLOSE 0x1f /* Used internally to schedule socket close */
/* Attributes */
#define BAF_OPTIONAL 0x80
#define BAF_TRANSITIVE 0x40
#define BAF_PARTIAL 0x20
#define BAF_EXT_LEN 0x10
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#define BA_ORIGIN 0x01 /* RFC 4271 */ /* WM */
#define BA_AS_PATH 0x02 /* WM */
#define BA_NEXT_HOP 0x03 /* WM */
#define BA_MULTI_EXIT_DISC 0x04 /* ON */
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#define BA_LOCAL_PREF 0x05 /* WD */
#define BA_ATOMIC_AGGR 0x06 /* WD */
#define BA_AGGREGATOR 0x07 /* OT */
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#define BA_COMMUNITY 0x08 /* RFC 1997 */ /* OT */
#define BA_ORIGINATOR_ID 0x09 /* RFC 4456 */ /* ON */
#define BA_CLUSTER_LIST 0x0a /* RFC 4456 */ /* ON */
#define BA_MP_REACH_NLRI 0x0e /* RFC 4760 */
#define BA_MP_UNREACH_NLRI 0x0f /* RFC 4760 */
#define BA_EXT_COMMUNITY 0x10 /* RFC 4360 */
#define BA_AS4_PATH 0x11 /* RFC 6793 */
#define BA_AS4_AGGREGATOR 0x12 /* RFC 6793 */
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#define BA_LARGE_COMMUNITY 0x20 /* RFC 8092 */
/* Bird's private internal BGP attributes */
#define BA_MPLS_LABEL_STACK 0xfe /* MPLS label stack transfer attribute */
/* BGP connection states */
#define BS_IDLE 0
#define BS_CONNECT 1 /* Attempting to connect */
#define BS_ACTIVE 2 /* Waiting for connection retry & listening */
#define BS_OPENSENT 3
#define BS_OPENCONFIRM 4
#define BS_ESTABLISHED 5
#define BS_CLOSE 6 /* Used during transition to BS_IDLE */
#define BS_MAX 7
/* BGP start states
*
* Used in PS_START for fine-grained specification of starting state.
*
* When BGP protocol is started by core, it goes to BSS_PREPARE. When BGP
* protocol done what is neccessary to start itself (like acquiring the lock),
* it goes to BSS_CONNECT.
*/
#define BSS_PREPARE 0 /* Used before ordinary BGP started, i. e. waiting for lock */
#define BSS_DELAY 1 /* Startup delay due to previous errors */
#define BSS_CONNECT 2 /* Ordinary BGP connecting */
/* BGP feed states (TX)
*
* RFC 4724 specifies that an initial feed should end with End-of-RIB mark.
*
* RFC 7313 specifies that a route refresh should be demarcated by BoRR and EoRR packets.
*
* These states (stored in c->feed_state) are used to keep track of these
* requirements. When such feed is started, BFS_LOADING / BFS_REFRESHING is
* set. When it ended, BFS_LOADED / BFS_REFRESHED is set to schedule End-of-RIB
* or EoRR packet. When the packet is sent, the state returned to BFS_NONE.
*
* Note that when a non-demarcated feed (e.g. plain RFC 4271 initial load
* without End-of-RIB or plain RFC 2918 route refresh without BoRR/EoRR
* demarcation) is active, BFS_NONE is set.
*
* BFS_NONE, BFS_LOADING and BFS_REFRESHING are also used as load states (RX)
* with correspondent semantics (-, expecting End-of-RIB, expecting EoRR).
*/
#define BFS_NONE 0 /* No feed or original non-demarcated feed */
#define BFS_LOADING 1 /* Initial feed active, End-of-RIB planned */
#define BFS_LOADED 2 /* Loading done, End-of-RIB marker scheduled */
#define BFS_REFRESHING 3 /* Route refresh (introduced by BoRR) active */
#define BFS_REFRESHED 4 /* Refresh done, EoRR packet scheduled */
/* Error classes */
#define BE_NONE 0
#define BE_MISC 1 /* Miscellaneous error */
#define BE_SOCKET 2 /* Socket error */
#define BE_BGP_RX 3 /* BGP protocol error notification received */
#define BE_BGP_TX 4 /* BGP protocol error notification sent */
#define BE_AUTO_DOWN 5 /* Automatic shutdown */
#define BE_MAN_DOWN 6 /* Manual shutdown */
/* Misc error codes */
#define BEM_NEIGHBOR_LOST 1
#define BEM_INVALID_NEXT_HOP 2
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#define BEM_INVALID_MD5 3 /* MD5 authentication kernel request failed (possibly not supported) */
#define BEM_NO_SOCKET 4
#define BEM_LINK_DOWN 5
#define BEM_BFD_DOWN 6
#define BEM_GRACEFUL_RESTART 7
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/* Automatic shutdown error codes */
#define BEA_ROUTE_LIMIT_EXCEEDED 1
/* Well-known communities */
#define BGP_COMM_NO_EXPORT 0xffffff01 /* Don't export outside local AS / confed. */
#define BGP_COMM_NO_ADVERTISE 0xffffff02 /* Don't export at all */
#define BGP_COMM_NO_EXPORT_SUBCONFED 0xffffff03 /* NO_EXPORT even in local confederation */
#define BGP_COMM_LLGR_STALE 0xffff0006 /* Route is stale according to LLGR */
#define BGP_COMM_NO_LLGR 0xffff0007 /* Do not treat the route according to LLGR */
/* Origins */
#define ORIGIN_IGP 0
#define ORIGIN_EGP 1
#define ORIGIN_INCOMPLETE 2
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#endif