summaryrefslogtreecommitdiffstats
path: root/proto/bgp/bgp.h
blob: 6ae594a60c69af6d637c9a8511781d66fb2bdb02 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/*
 *	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_

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 */
  int next_hop_self;			/* Always set next hop to local IP address */
  unsigned connect_retry_time;
  unsigned hold_time, initial_hold_time;
  unsigned keepalive_time;
};

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_arg, notify_arg_size;
  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 */
  node bgp_node;			/* Node in global BGP protocol list */
  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 */
};

#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, unsigned data, unsigned len);
void bgp_close_conn(struct bgp_conn *c);

/* attrs.c */

struct rta *bgp_decode_attrs(struct bgp_conn *conn, byte *a, unsigned int len, struct linpool *pool);
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 *);
struct ea_list *bgp_path_prepend(struct linpool *pool, struct eattr *a, struct ea_list *old, int as);

/* 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);

/* 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 */

#define BGP_PATH_AS_SET		1	/* Types of path segments */
#define BGP_PATH_AS_SEQUENCE	2

/* 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

#endif