bird/proto/bgp/bgp.h
2021-10-13 19:09:04 +02:00

758 lines
27 KiB
C

/*
* 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.
*
* 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"
#include "nest/route.h"
#include "nest/bfd.h"
//#include "lib/lists.h"
#include "lib/hash.h"
#include "lib/socket.h"
struct linpool;
struct eattr;
/* 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);
};
struct bgp_config {
struct proto_config c;
u32 local_as, remote_as;
ip_addr local_ip; /* Source address to use */
ip_addr remote_ip;
struct iface *iface; /* Interface for link-local addresses */
u16 local_port; /* Local listening port */
u16 remote_port; /* Neighbor destination port */
int peer_type; /* Internal or external BGP (BGP_PT_*, optional) */
int multihop; /* Number of hops if multihop */
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] */
int enable_hostname; /* Enable local support for hostname [draft] */
u32 rr_cluster_id; /* Route reflector cluster ID, if different from local ID */
int rr_client; /* Whether neighbor is RR client of me */
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 */
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 allow_as_sets; /* Allow AS_SETs in incoming AS_PATHs */
int enforce_first_as; /* Enable check for neighbor AS as first AS in AS_PATH */
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 */
/* 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 */
const char *password; /* Password used for MD5 authentication */
net_addr *remote_range; /* Allowed neighbor range for dynamic BGP */
const char *dynamic_name; /* Name pattern for dynamic BGP */
int dynamic_name_digits; /* Minimum number of digits for dynamic names */
int check_link; /* Use iface link state for liveness detection */
struct bfd_options *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 mandatory; /* Channel is mandatory in capability negotiation */
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 aigp; /* AIGP is allowed on this session */
u8 aigp_originate; /* AIGP is originated automatically */
u32 cost; /* IGP cost for direct next hops */
u8 import_table; /* Use c.in_table as Adj-RIB-In */
u8 export_table; /* Use c.out_table as Adj-RIB-Out */
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 BGP_PT_INTERNAL 1
#define BGP_PT_EXTERNAL 2
#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 */
/* rte->pflags */
#define BGP_REF_SUPPRESSED 0x1 /* Used for deterministic MED comparison */
#define BGP_REF_STALE 0x2 /* Route is LLGR_STATE */
#define BGP_REF_NOT_STALE 0x4 /* Route is NOT LLGR_STATE */
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 */
u8 any_ext_next_hop; /* Bitwise OR of per-AF ext_next_hop */
u8 any_add_path; /* Bitwise OR of per-AF add_path */
const char *hostname; /* Hostname, RFC draft */
u16 af_count; /* Number of af_data items */
u16 length; /* Length of capabilities in OPEN msg */
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_stats {
uint rx_messages, tx_messages;
uint rx_updates, tx_updates;
u64 rx_bytes, tx_bytes;
uint fsm_established_transitions;
};
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 */
u32 received_as; /* ASN received in OPEN message */
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 */
};
struct bgp_proto {
struct proto p;
const struct bgp_config *cf; /* Shortcut to BGP configuration */
ip_addr local_ip, remote_ip;
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 */
u8 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 ipv4; /* Use IPv4 connection, i.e. remote_ip is IPv4 */
u8 passive; /* Do not initiate outgoing connection */
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 */
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 */
struct birdsock *postponed_sk; /* Postponed incoming socket for dynamic BGP */
struct bgp_stats stats; /* BGP statistics */
btime last_established; /* Last time of enter/leave of established state */
btime last_rx_update; /* Last time of RX update */
ip_addr link_addr; /* Link-local version of local_ip */
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 */
int dynamic_name_counter; /* Counter for dynamic BGP names */
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_* */
};
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];
};
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 */
ea_list eattrs[0]; /* Per-bucket extended attributes */
};
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;
uint local_next_hop;
};
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;
};
#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
#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);
}
extern struct linpool *bgp_linpool;
extern struct linpool *bgp_linpool2;
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);
void bgp_close_conn(struct bgp_conn *c);
void bgp_update_startup_delay(struct bgp_proto *p);
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, int 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);
static inline int
rte_resolvable(rte *rt)
{
return rt->attrs->dest == RTD_UNICAST;
}
#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);
bmemcpy(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_mp_reach_mrt(struct bgp_write_state *s, eattr *a, byte *buf, uint size);
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_finish_attrs(struct bgp_parse_state *s, rta *a);
void bgp_init_bucket_table(struct bgp_channel *c);
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);
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);
u32 bgp_rte_igp_metric(struct rte *);
void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old);
int bgp_preexport(struct proto *, struct rte *);
int bgp_get_attr(const struct eattr *e, byte *buf, int buflen);
void bgp_get_route_info(struct rte *, byte *buf);
int bgp_total_aigp_metric_(rte *e, u64 *metric, const struct adata **ad);
#define BGP_AIGP_METRIC 1
#define BGP_AIGP_MAX U64(0xffffffffffffffff)
static inline u64
bgp_total_aigp_metric(rte *r)
{
u64 metric = BGP_AIGP_MAX;
const struct adata *ad;
bgp_total_aigp_metric_(r, &metric, &ad);
return metric;
}
/* packets.c */
void bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new);
void bgp_prepare_capabilities(struct bgp_conn *conn);
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);
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);
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] */
#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
#define BAF_DECODE_FLAGS 0x0100 /* Private flag - attribute flags are handled by the decode hook */
#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 */
#define BA_LOCAL_PREF 0x05 /* WD */
#define BA_ATOMIC_AGGR 0x06 /* WD */
#define BA_AGGREGATOR 0x07 /* OT */
#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 */
#define BA_AIGP 0x1a /* RFC 7311 */
#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
#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
/* 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
#endif