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/*
* BIRD -- The Border Gateway Protocol
*
* (c) 2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_BGP_H_
#define _BIRD_BGP_H_
#include "nest/route.h"
struct linpool;
struct eattr;
struct bgp_config {
struct proto_config c;
unsigned int local_as, remote_as;
ip_addr remote_ip;
int multihop; /* Number of hops if multihop */
ip_addr multihop_via; /* Multihop: address to route to */
ip_addr source_addr; /* Source address to use */
int next_hop_self; /* Always set next hop to local IP address */
int compare_path_lengths; /* Use path lengths when selecting best route */
u32 default_local_pref; /* Default value for LOCAL_PREF attribute */
u32 default_med; /* Default value for MULTI_EXIT_DISC attribute */
unsigned connect_retry_time;
unsigned hold_time, initial_hold_time;
unsigned keepalive_time;
unsigned start_delay_time; /* Minimum delay between connects */
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 */
};
struct bgp_conn {
struct bgp_proto *bgp;
struct birdsock *sk;
unsigned int state; /* State of connection state machine */
struct timer *connect_retry_timer;
struct timer *hold_timer;
struct timer *keepalive_timer;
int packets_to_send; /* Bitmap of packet types to be sent */
int notify_code, notify_subcode, notify_size;
byte *notify_data;
int error_flag; /* Error state, ignore all input */
int primary; /* This connection is primary */
unsigned hold_time, keepalive_time; /* Times calculated from my and neighbor's requirements */
};
struct bgp_proto {
struct proto p;
struct bgp_config *cf; /* Shortcut to BGP configuration */
unsigned local_as, remote_as;
int is_internal; /* Internal BGP connection (local_as == remote_as) */
u32 local_id; /* BGP identifier of this router */
u32 remote_id; /* BGP identifier of the neighbor */
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 */
ip_addr next_hop; /* Either the peer or multihop_via */
struct neighbor *neigh; /* Neighbor entry corresponding to next_hop */
ip_addr local_addr; /* Address of the local end of the link to next_hop */
struct bgp_bucket **bucket_hash; /* Hash table of attribute buckets */
unsigned int hash_size, hash_count, hash_limit;
struct fib prefix_fib; /* Prefixes to be sent */
list bucket_queue; /* Queue of buckets to send */
struct bgp_bucket *withdraw_bucket; /* Withdrawn routes */
unsigned startup_delay; /* Time to delay protocol startup by due to errors */
bird_clock_t last_connect; /* Time of last connect attempt */
#ifdef IPV6
byte *mp_reach_start, *mp_unreach_start; /* Multiprotocol BGP attribute notes */
unsigned mp_reach_len, mp_unreach_len;
#endif
};
struct bgp_prefix {
struct fib_node n; /* Node in prefix fib */
node bucket_node; /* Node in per-bucket list */
};
struct bgp_bucket {
node send_node; /* Node in send queue */
struct bgp_bucket *hash_next, *hash_prev; /* Node in bucket hash table */
unsigned hash; /* Hash over extended attributes */
list prefixes; /* Prefixes in this buckets */
ea_list eattrs[0]; /* Per-bucket extended attributes */
};
#define BGP_PORT 179
#define BGP_VERSION 4
#define BGP_HEADER_LENGTH 19
#define BGP_MAX_PACKET_LENGTH 4096
#define BGP_RX_BUFFER_SIZE 4096
#define BGP_TX_BUFFER_SIZE BGP_MAX_PACKET_LENGTH
extern struct linpool *bgp_linpool;
void bgp_start_timer(struct timer *t, int value);
void bgp_check(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);
#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)
/* attrs.c */
byte *bgp_attach_attr(struct ea_list **to, struct linpool *, unsigned attr, unsigned val);
struct rta *bgp_decode_attrs(struct bgp_conn *conn, byte *a, unsigned int len, struct linpool *pool, int mandatory);
int bgp_get_attr(struct eattr *e, byte *buf);
int bgp_rte_better(struct rte *, struct rte *);
void bgp_rt_notify(struct proto *, struct network *, struct rte *, struct rte *, struct ea_list *);
int bgp_import_control(struct proto *, struct rte **, struct ea_list **, struct linpool *);
void bgp_attr_init(struct bgp_proto *);
unsigned int bgp_encode_attrs(byte *w, struct ea_list *attrs, int remains);
void bgp_free_bucket(struct bgp_proto *p, struct bgp_bucket *buck);
/* packets.c */
void bgp_schedule_packet(struct bgp_conn *conn, int type);
void bgp_tx(struct birdsock *sk);
int bgp_rx(struct birdsock *sk, int size);
void bgp_log_error(struct bgp_proto *p, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
/* Packet types */
#define PKT_OPEN 0x01
#define PKT_UPDATE 0x02
#define PKT_NOTIFICATION 0x03
#define PKT_KEEPALIVE 0x04
#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 BA_ORIGIN 0x01 /* [RFC1771] */ /* 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 /* [RFC1997] */ /* OT */
#define BA_ORIGINATOR_ID 0x09 /* [RFC1966] */ /* ON */
#define BA_CLUSTER_LIST 0x0a /* ON */
/* We don't support these: */
#define BA_DPA 0x0b /* ??? */
#define BA_ADVERTISER 0x0c /* [RFC1863] */
#define BA_RCID_PATH 0x0d
#define BA_MP_REACH_NLRI 0x0e /* [RFC2283] */
#define BA_MP_UNREACH_NLRI 0x0f
#define BA_EXTENDED_COMM 0x10 /* draft-ramachandra-bgp-ext-communities */
/* BGP 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
/* 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 */
/* Origins */
#define ORIGIN_IGP 0
#define ORIGIN_EGP 1
#define ORIGIN_INCOMPLETE 2
/* Address families */
#define BGP_AF_IPV6 2
#endif
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