91adb887fcb1ca4d07a8933c03e141a048c2db94
[l2tpns.git] / bgp.h
1 /* BGPv4 (RFC1771) */
2 /* $Id: bgp.h,v 1.5 2005/06/04 15:42:35 bodea Exp $ */
3
4 #ifndef __BGP_H__
5 #define __BGP_H__
6
7 #define BGP_MAX_PACKET_SIZE 4096
8 #define BGP_HOLD_TIME 180 /* seconds before peer times us out */
9 #define BGP_KEEPALIVE_TIME 60 /* seconds between messages */
10 #define BGP_STATE_TIME 60 /* state transition timeout in seconds */
11 #define BGP_MAX_RETRY 42 /* maximum number of times to retry */
12 #define BGP_RETRY_BACKOFF 60 /* number of seconds between retries,
13 cumulative */
14
15 #define BGP_METRIC 1 /* multi_exit_disc */
16 #define BGP_LOCAL_PREF 100 /* local preference value */
17
18 struct bgp_header {
19 char marker[16];
20 uint16_t len;
21 uint8_t type;
22 } __attribute__ ((packed));
23
24 /* bgp_header.type */
25 #define BGP_MSG_OPEN 1
26 #define BGP_MSG_UPDATE 2
27 #define BGP_MSG_NOTIFICATION 3
28 #define BGP_MSG_KEEPALIVE 4
29
30 struct bgp_packet {
31 struct bgp_header header;
32 char data[BGP_MAX_PACKET_SIZE - sizeof(struct bgp_header)]; /* variable */
33 } __attribute__ ((packed));
34
35 struct bgp_data_open {
36 uint8_t version;
37 #define BGP_VERSION 4
38 uint16_t as;
39 uint16_t hold_time;
40 uint32_t identifier;
41 uint8_t opt_len;
42 #define BGP_DATA_OPEN_SIZE 10 /* size of struct excluding opt_params */
43 char opt_params[sizeof(((struct bgp_packet *)0)->data) - BGP_DATA_OPEN_SIZE]; /* variable */
44 } __attribute__ ((packed));
45
46 struct bgp_opt_param {
47 uint8_t type;
48 uint8_t len;
49 #define BGP_MAX_OPT_PARAM_SIZE 256
50 char value[BGP_MAX_OPT_PARAM_SIZE];
51 } __attribute__ ((packed));
52
53 #define BGP_PARAM_TYPE_CAPABILITY 2
54 struct bgp_capability {
55 uint8_t code;
56 uint8_t len;
57 #define BGP_MAX_CAPABILITY_SIZE 256
58 char value[BGP_MAX_CAPABILITY_SIZE];
59 } __attribute__ ((packed));
60
61 /* RFC4760 Multiprotocol extension */
62 #define BGP_CAP_CODE_MP 1
63
64 struct bgp_mp_cap_param {
65 uint16_t afi; /* sa_family_t */
66 uint8_t reserved; /* SHOULD be 0 */
67 uint8_t safi;
68 } __attribute__ ((packed));
69
70 /* bgp_mp_cap_param.safi */
71 #define BGP_MP_SAFI_UNICAST 1
72 #define BGP_MP_SAFI_MULTICAST 2
73
74 struct bgp_ip_prefix {
75 uint8_t len;
76 uint32_t prefix; /* variable */
77 } __attribute__ ((packed));
78
79 #define BGP_IP_PREFIX_SIZE(p) (1 + ((p).len / 8) + ((p).len % 8 != 0))
80
81 struct bgp_path_attr {
82 uint8_t flags;
83 uint8_t code;
84 union {
85 struct {
86 uint8_t len;
87 char value[29]; /* semi-random size, adequate for l2tpns */
88 } __attribute__ ((packed)) s; /* short */
89 struct {
90 uint16_t len;
91 char value[28];
92 } __attribute__ ((packed)) e; /* extended */
93 } data; /* variable */
94 } __attribute__ ((packed));
95
96 /* bgp_path_attr.flags (bitfields) */
97 #define BGP_PATH_ATTR_FLAG_OPTIONAL (1 << 7)
98 #define BGP_PATH_ATTR_FLAG_TRANS (1 << 6)
99 #define BGP_PATH_ATTR_FLAG_PARTIAL (1 << 5)
100 #define BGP_PATH_ATTR_FLAG_EXTLEN (1 << 4)
101
102 /* bgp_path_attr.code, ...value */
103 #define BGP_PATH_ATTR_CODE_ORIGIN 1 /* well-known, mandatory */
104 # define BGP_PATH_ATTR_CODE_ORIGIN_IGP 0
105 # define BGP_PATH_ATTR_CODE_ORIGIN_EGP 1
106 # define BGP_PATH_ATTR_CODE_ORIGIN_INCOMPLETE 2
107 #define BGP_PATH_ATTR_CODE_AS_PATH 2 /* well-known, mandatory */
108 # define BGP_PATH_ATTR_CODE_AS_PATH_AS_SET 1
109 # define BGP_PATH_ATTR_CODE_AS_PATH_AS_SEQUENCE 2
110 #define BGP_PATH_ATTR_CODE_NEXT_HOP 3 /* well-known, mandatory */
111 #define BGP_PATH_ATTR_CODE_MULTI_EXIT_DISC 4 /* optional, non-transitive */
112 #define BGP_PATH_ATTR_CODE_LOCAL_PREF 5 /* well-known, discretionary */
113 #define BGP_PATH_ATTR_CODE_ATOMIC_AGGREGATE 6 /* well-known, discretionary */
114 #define BGP_PATH_ATTR_CODE_AGGREGATOR 7 /* optional, transitive */
115 #define BGP_PATH_ATTR_CODE_COMMUNITIES 8 /* optional, transitive (RFC1997) */
116
117 #define BGP_PATH_ATTR_SIZE(p) ((((p).flags & BGP_PATH_ATTR_FLAG_EXTLEN) \
118 ? ((p).data.e.len + 1) : (p).data.s.len) + 3)
119
120 /* well known COMMUNITIES */
121 #define BGP_COMMUNITY_NO_EXPORT 0xffffff01 /* don't advertise outside confederation */
122 #define BGP_COMMUNITY_NO_ADVERTISE 0xffffff02 /* don't advertise to any peer */
123 #define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03 /* don't advertise to any other AS */
124
125 struct bgp_data_notification {
126 uint8_t error_code;
127 uint8_t error_subcode;
128 char data[sizeof(((struct bgp_packet *)0)->data) - 2]; /* variable */
129 } __attribute__ ((packed));
130
131 /* bgp_data_notification.error_code, .error_subcode */
132 #define BGP_ERR_UNSPEC 0
133 #define BGP_ERR_HEADER 1
134 # define BGP_ERR_HDR_NOT_SYNC 1
135 # define BGP_ERR_HDR_BAD_LEN 2
136 # define BGP_ERR_HDR_BAD_TYPE 3
137 #define BGP_ERR_OPEN 2
138 # define BGP_ERR_OPN_VERSION 1
139 # define BGP_ERR_OPN_BAD_AS 2
140 # define BGP_ERR_OPN_BAD_IDENT 3
141 # define BGP_ERR_OPN_UNSUP_PARAM 4
142 # define BGP_ERR_OPN_AUTH_FAILURE 5
143 # define BGP_ERR_OPN_HOLD_TIME 6
144 # define BGP_ERR_OPN_UNSUP_CAP 7
145 #define BGP_ERR_UPDATE 3
146 # define BGP_ERR_UPD_BAD_ATTR_LIST 1
147 # define BGP_ERR_UPD_UNKN_WK_ATTR 2
148 # define BGP_ERR_UPD_MISS_WK_ATTR 3
149 # define BGP_ERR_UPD_BAD_ATTR_FLAG 4
150 # define BGP_ERR_UPD_BAD_ATTR_LEN 5
151 # define BGP_ERR_UPD_BAD_ORIGIN 6
152 # define BGP_ERR_UPD_ROUTING_LOOP 7
153 # define BGP_ERR_UPD_BAD_NEXT_HOP 8
154 # define BGP_ERR_UPD_BAD_OPT_ATTR 9
155 # define BGP_ERR_UPD_BAD_NETWORK 10
156 # define BGP_ERR_UPD_BAD_AS_PATH 11
157 #define BGP_ERR_HOLD_TIMER_EXP 4
158 #define BGP_ERR_FSM 5
159 #define BGP_ERR_CEASE 6
160
161 enum bgp_state {
162 Disabled, /* initial, or failed */
163 Idle, /* trying to connect */
164 Connect, /* connect issued */
165 Active, /* connected, waiting to send OPEN */
166 OpenSent, /* OPEN sent, waiting for peer OPEN */
167 OpenConfirm, /* KEEPALIVE sent, waiting for peer KEEPALIVE */
168 Established, /* established */
169 };
170
171 struct bgp_route_list {
172 struct bgp_ip_prefix dest;
173 struct bgp_route_list *next;
174 };
175
176 struct bgp_buf {
177 struct bgp_packet packet; /* BGP packet */
178 size_t done; /* bytes sent/recvd */
179 };
180
181 /* state */
182 struct bgp_peer {
183 char name[32]; /* peer name */
184 in_addr_t addr; /* peer address */
185 int as; /* AS number */
186 int sock;
187 enum bgp_state state; /* FSM state */
188 enum bgp_state next_state; /* next state after outbuf cleared */
189 time_t state_time; /* time of last state change */
190 time_t keepalive_time; /* time to send next keepalive */
191 time_t retry_time; /* time for connection retry */
192 int retry_count; /* connection retry count */
193 int init_keepalive; /* initial keepalive time */
194 int init_hold; /* initial hold time */
195 int keepalive; /* negotiated keepalive time */
196 int hold; /* negotiated hold time */
197 time_t expire_time; /* time next peer packet expected */
198 int routing; /* propagate routes */
199 int update_routes; /* UPDATE required */
200 struct bgp_route_list *routes; /* routes known by this peer */
201 struct bgp_buf *outbuf; /* pending output */
202 struct bgp_buf *inbuf; /* pending input */
203 int cli_flag; /* updates requested from CLI */
204 char *path_attrs; /* path attrs to send in UPDATE message */
205 int path_attr_len; /* length of path attrs */
206 uint32_t events; /* events to poll */
207 struct event_data edata; /* poll data */
208 int handle_ipv6_routes; /* can handle IPv6 routes advertisements */
209 };
210
211 /* bgp_peer.cli_flag */
212 #define BGP_CLI_SUSPEND 1
213 #define BGP_CLI_ENABLE 2
214 #define BGP_CLI_RESTART 3
215
216 extern struct bgp_peer *bgp_peers;
217 extern int bgp_configured;
218
219 /* actions */
220 int bgp_setup(int as);
221 int bgp_start(struct bgp_peer *peer, char *name, int as, int keepalive,
222 int hold, int enable);
223
224 void bgp_stop(struct bgp_peer *peer);
225 void bgp_halt(struct bgp_peer *peer);
226 int bgp_restart(struct bgp_peer *peer);
227 int bgp_add_route(in_addr_t ip, in_addr_t mask);
228 int bgp_del_route(in_addr_t ip, in_addr_t mask);
229 void bgp_enable_routing(int enable);
230 int bgp_set_poll(void);
231 int bgp_process(uint32_t events[]);
232 char const *bgp_state_str(enum bgp_state state);
233
234 extern char const *cvs_id_bgp;
235
236 #endif /* __BGP_H__ */