X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/b4451ee1a4e9b38331aee04e53092c3a2ee84b50..c239d4b22829335fda98b66ce045a3f624436eeb:/bgp.h diff --git a/bgp.h b/bgp.h new file mode 100644 index 0000000..635a65d --- /dev/null +++ b/bgp.h @@ -0,0 +1,202 @@ +/* BGPv4 (RFC1771) */ +/* $Id: bgp.h,v 1.1 2004-06-23 03:52:24 fred_nerk Exp $ */ + +#ifndef __BGP_H__ +#define __BGP_H__ + +#define BGP_MAX_PACKET_SIZE 4096 +#define BGP_HOLD_TIME 180 /* seconds before peer times us out */ +#define BGP_KEEPALIVE_TIME 60 /* seconds between messages */ +#define BGP_MAX_RETRY 42 /* maximum number of times to retry */ +#define BGP_RETRY_BACKOFF 60 /* number of seconds between retries, + cumulative */ + +#define BGP_METRIC 1 /* multi_exit_disc */ +#define BGP_LOCAL_PREF 100 /* local preference value */ + +struct bgp_header { + char marker[16]; + u16 len; + u8 type; +} __attribute__ ((packed)); + +/* bgp_header.type */ +#define BGP_MSG_OPEN 1 +#define BGP_MSG_UPDATE 2 +#define BGP_MSG_NOTIFICATION 3 +#define BGP_MSG_KEEPALIVE 4 + +struct bgp_packet { + struct bgp_header header; + char data[BGP_MAX_PACKET_SIZE - sizeof(struct bgp_header)]; /* variable */ +} __attribute__ ((packed)); + +struct bgp_data_open { + u8 version; +#define BGP_VERSION 4 + u16 as; + u16 hold_time; + u32 identifier; + u8 opt_len; +#define BGP_DATA_OPEN_SIZE 10 /* size of struct excluding opt_params */ + char opt_params[sizeof(((struct bgp_packet *)0)->data) - BGP_DATA_OPEN_SIZE]; /* variable */ +} __attribute__ ((packed)); + +struct bgp_ip_prefix { + u8 len; + u32 prefix; /* variable */ +} __attribute__ ((packed)); + +#define BGP_IP_PREFIX_SIZE(p) (1 + ((p).len / 8) + ((p).len % 8 != 0)) + +struct bgp_path_attr { + u8 flags; + u8 code; + union { + struct { + u8 len; + char value[29]; /* semi-random size, adequate for l2tpns */ + } __attribute__ ((packed)) s; /* short */ + struct { + u16 len; + char value[28]; + } __attribute__ ((packed)) e; /* extended */ + } data; /* variable */ +} __attribute__ ((packed)); + +/* bgp_path_attr.flags (bitfields) */ +#define BGP_PATH_ATTR_FLAG_OPTIONAL (1 << 7) +#define BGP_PATH_ATTR_FLAG_TRANS (1 << 6) +#define BGP_PATH_ATTR_FLAG_PARTIAL (1 << 5) +#define BGP_PATH_ATTR_FLAG_EXTLEN (1 << 4) + +/* bgp_path_attr.code, ...value */ +#define BGP_PATH_ATTR_CODE_ORIGIN 1 /* well-known, mandatory */ +# define BGP_PATH_ATTR_CODE_ORIGIN_IGP 0 +# define BGP_PATH_ATTR_CODE_ORIGIN_EGP 1 +# define BGP_PATH_ATTR_CODE_ORIGIN_INCOMPLETE 2 +#define BGP_PATH_ATTR_CODE_AS_PATH 2 /* well-known, mandatory */ +# define BGP_PATH_ATTR_CODE_AS_PATH_AS_SET 1 +# define BGP_PATH_ATTR_CODE_AS_PATH_AS_SEQUENCE 2 +#define BGP_PATH_ATTR_CODE_NEXT_HOP 3 /* well-known, mandatory */ +#define BGP_PATH_ATTR_CODE_MULTI_EXIT_DISC 4 /* optional, non-transitive */ +#define BGP_PATH_ATTR_CODE_LOCAL_PREF 5 /* well-known, discretionary */ +#define BGP_PATH_ATTR_CODE_ATOMIC_AGGREGATE 6 /* well-known, discretionary */ +#define BGP_PATH_ATTR_CODE_AGGREGATOR 7 /* optional, transitive */ +#define BGP_PATH_ATTR_CODE_COMMUNITIES 8 /* optional, transitive (RFC1997) */ + +#define BGP_PATH_ATTR_SIZE(p) ((((p).flags & BGP_PATH_ATTR_FLAG_EXTLEN) \ + ? ((p).data.e.len + 1) : (p).data.s.len) + 3) + +/* well known COMMUNITIES */ +#define BGP_COMMUNITY_NO_EXPORT 0xffffff01 /* don't advertise outside confederation */ +#define BGP_COMMUNITY_NO_ADVERTISE 0xffffff02 /* don't advertise to any peer */ +#define BGP_COMMUNITY_NO_EXPORT_SUBCONFED 0xffffff03 /* don't advertise to any other AS */ + +struct bgp_data_notification { + u8 error_code; + u8 error_subcode; + char data[sizeof(((struct bgp_packet *)0)->data) - 2]; /* variable */ +} __attribute__ ((packed)); + +/* bgp_data_notification.error_code, .error_subcode */ +#define BGP_ERR_HEADER 1 +# define BGP_ERR_HDR_NOT_SYNC 1 +# define BGP_ERR_HDR_BAD_LEN 2 +# define BGP_ERR_HDR_BAD_TYPE 3 +#define BGP_ERR_OPEN 2 +# define BGP_ERR_OPN_VERSION 1 +# define BGP_ERR_OPN_BAD_AS 2 +# define BGP_ERR_OPN_BAD_IDENT 3 +# define BGP_ERR_OPN_UNSUP_PARAM 4 +# define BGP_ERR_OPN_AUTH_FAILURE 5 +# define BGP_ERR_OPN_HOLD_TIME 6 +#define BGP_ERR_UPDATE 3 +# define BGP_ERR_UPD_BAD_ATTR_LIST 1 +# define BGP_ERR_UPD_UNKN_WK_ATTR 2 +# define BGP_ERR_UPD_MISS_WK_ATTR 3 +# define BGP_ERR_UPD_BAD_ATTR_FLAG 4 +# define BGP_ERR_UPD_BAD_ATTR_LEN 5 +# define BGP_ERR_UPD_BAD_ORIGIN 6 +# define BGP_ERR_UPD_ROUTING_LOOP 7 +# define BGP_ERR_UPD_BAD_NEXT_HOP 8 +# define BGP_ERR_UPD_BAD_OPT_ATTR 9 +# define BGP_ERR_UPD_BAD_NETWORK 10 +# define BGP_ERR_UPD_BAD_AS_PATH 11 +#define BGP_ERR_HOLD_TIMER_EXP 4 +#define BGP_ERR_FSM 5 +#define BGP_ERR_CEASE 6 + +enum bgp_state { + Disabled, /* initial, or failed */ + Idle, /* trying to connect */ + Connect, /* connect issued */ + Active, /* connected, waiting to send OPEN */ + OpenSent, /* OPEN sent, waiting for peer OPEN */ + OpenConfirm, /* KEEPALIVE sent, waiting for peer KEEPALIVE */ + Established, /* established */ +}; + +struct bgp_route_list { + struct bgp_ip_prefix dest; + struct bgp_route_list *next; +}; + +struct bgp_buf { + struct bgp_packet packet; /* BGP packet */ + size_t done; /* bytes sent/recvd */ +}; + +/* state */ +struct bgp_peer { + char name[32]; /* peer name */ + in_addr_t addr; /* peer address */ + int as; /* AS number */ + int sock; + enum bgp_state state; /* FSM state */ + enum bgp_state next_state; /* next state after outbuf cleared */ + time_t state_time; /* time of last state change */ + time_t keepalive_time; /* time to send next keepalive */ + time_t retry_time; /* time for connection retry */ + int retry_count; /* connection retry count */ + int hold; /* hold time from peer */ + time_t expire_time; /* time next peer packet expected */ + int routing; /* propagate routes */ + int update_routes; /* UPDATE required */ + struct bgp_route_list *routes; /* routes known by this peer */ + struct bgp_buf *outbuf; /* pending output */ + struct bgp_buf *inbuf; /* pending input */ + int cli_flag; /* updates requested from CLI */ + char *path_attrs; /* path attrs to send in UPDATE message */ + int path_attr_len; /* length of path attrs */ +}; + +/* bgp_peer.cli_flag */ +#define BGP_CLI_SUSPEND 1 +#define BGP_CLI_ENABLE 2 +#define BGP_CLI_RESTART 3 + +#define BGP_NUM_PEERS 2 +extern struct bgp_peer *bgp_peers; +extern struct bgp_route_list *bgp_routes; +extern int bgp_configured; + +/* actions */ +int bgp_setup(int as); +int bgp_start(struct bgp_peer *peer, char *name, int as, int enable); +void bgp_stop(struct bgp_peer *peer); +void bgp_halt(struct bgp_peer *peer); +int bgp_restart(struct bgp_peer *peer); +int bgp_add_route(in_addr_t ip, in_addr_t mask); +int bgp_del_route(in_addr_t ip, in_addr_t mask); +void bgp_enable_routing(int enable); +int bgp_select_state(struct bgp_peer *peer); +int bgp_process(struct bgp_peer *peer, int readable, int writable); + +/* CLI */ +int cmd_show_bgp(struct cli_def *cli, char *command, char **argv, int argc); +int cmd_suspend_bgp(struct cli_def *cli, char *command, char **argv, int argc); +int cmd_no_suspend_bgp(struct cli_def *cli, char *command, char **argv, int argc); +int cmd_restart_bgp(struct cli_def *cli, char *command, char **argv, int argc); + +#endif /* __BGP_H__ */