/* * BIRD -- The Border Gateway Protocol * * (c) 2000 Martin Mares * (c) 2008--2016 Ondrej Zajicek * (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 #include #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 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, ea_list *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, ea_list **to); }; 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 free_bind; /* Bind listening socket with SKF_FREEBIND */ 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_enhanced_refresh; /* Enable local support for enhanced route refresh [RFC 7313] */ int enable_as4; /* Enable local support for 4B AS numbers [RFC 6793] */ int enable_extended_messages; /* Enable local support for extended messages [RFC 8654] */ 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_med; /* Allow BGP_MED 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 */ u8 local_role; /* Set peering role with neighbor [RFC 9234] */ int require_roles; /* Require configured roles on both sides */ /* 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; unsigned min_hold_time; /* Minimum accepted hold time */ unsigned initial_hold_time; unsigned keepalive_time; unsigned min_keepalive_time; /* Minimum accepted 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 next_hop_prefer; /* Prefer global or link-local next hop (NHP_*) */ 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 validate; /* Validate Flowspec per RFC 8955 (6) */ 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; /* Keep Adj-RIB-Out and export it */ 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 */ struct rtable_config *base_table; /* Base table for Flowspec validation */ }; #define BGP_PT_INTERNAL 1 #define BGP_PT_EXTERNAL 2 #define BGP_ROLE_UNDEFINED 255 #define BGP_ROLE_PROVIDER 0 #define BGP_ROLE_RS_SERVER 1 #define BGP_ROLE_RS_CLIENT 2 #define BGP_ROLE_CUSTOMER 3 #define BGP_ROLE_PEER 4 #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 NHP_GLOBAL 1 #define NHP_LOCAL 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 */ 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 8950 */ 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 8654 */ u8 route_refresh; /* Route refresh capability, RFC 2918 */ u8 enhanced_refresh; /* Enhanced route refresh, RFC 7313 */ u8 role; /* BGP role capability, RFC 9234 */ 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 */ list requests; /* Listen requests */ sock *sk; /* Real listening socket */ }; 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 */ byte *local_open_msg; /* Saved OPEN messages (no header) */ byte *remote_open_msg; uint local_open_length; uint remote_open_length; 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_listen_request { node n; /* Node in bgp_socket / pending list */ struct bgp_socket *sock; /* Assigned socket */ ip_addr addr; struct iface *iface; struct iface *vrf; uint port; uint flags; }; 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_listen_request listen; /* Shared listening socket */ struct bfd_request *bfd_req; /* BFD request, if BFD is used */ struct birdsock *postponed_sk; /* Postponed incoming socket for dynamic BGP */ event *uncork_ev; /* Uncork event in case of congestion */ 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 */ rtable *base_table; /* Base table for Flowspec validation */ /* Rest are zeroed when down */ pool *pool; struct bgp_pending_tx *ptx; /* Routes waiting to be sent */ struct rt_exporter prefix_exporter; /* Table-like exporter for ptx */ 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 */ struct rt_export_request stale_feed; /* Feeder request for stale route modification */ 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_* */ u8 feed_out_table; /* Refeed into out_table */ }; struct bgp_prefix { node buck_node_xx; /* Node in per-bucket list */ struct bgp_prefix *next; /* Node in prefix hash table */ struct bgp_bucket *last; /* Last bucket sent with this prefix */ struct bgp_bucket *cur; /* Current bucket (cur == last) if no update is required */ btime lastmod; /* Last modification of this prefix */ 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 to send in this bucket (struct bgp_prefix) */ u32 hash; /* Hash over extended attributes */ u32 px_uc:31; /* How many prefixes are linking this bucket */ u32 bmp:1; /* Temporary bucket for BMP encoding */ ea_list eattrs[0]; /* Per-bucket extended attributes */ }; struct bgp_pending_tx { resource r; 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 */ }; 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_reject; 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; int reach_nlri_step; 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; /* Cached state for bgp_rte_update() */ u32 last_id; struct rte_src *last_src; ea_list *cached_ea; }; #define BGP_PORT 179 #define BGP_VERSION 4 #define BGP_HEADER_LENGTH 19 #define BGP_HDR_MARKER_LENGTH 16 #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 #define BGP_CF_WALK_CHANNELS(P,C) WALK_LIST(C, P->c.channels) if (C->c.class == &channel_bgp) #define BGP_WALK_CHANNELS(P,C) WALK_LIST(C, P->p.channels) if (C->c.class == &channel_bgp) #define BGP_MSG_HDR_MARKER_SIZE 16 #define BGP_MSG_HDR_MARKER_POS 0 #define BGP_MSG_HDR_LENGTH_SIZE 2 #define BGP_MSG_HDR_LENGTH_POS BGP_MSG_HDR_MARKER_SIZE #define BGP_MSG_HDR_TYPE_SIZE 1 #define BGP_MSG_HDR_TYPE_POS (BGP_MSG_HDR_MARKER_SIZE + BGP_MSG_HDR_LENGTH_SIZE) 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 int bgp_channel_is_role_applicable(struct bgp_channel *c) { return (c->afi == BGP_AF_IPV4 || c->afi == BGP_AF_IPV6); } static inline int bgp_cc_is_role_applicable(struct bgp_channel_config *c) { return (c->afi == BGP_AF_IPV4 || c->afi == BGP_AF_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); } void bgp_start_timer(struct bgp_proto *p, 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); const char *bgp_format_role_name(u8 role); static inline int rte_resolvable(const rte *rt) { eattr *nhea = ea_find(rt->attrs, &ea_gen_nexthop); if (!nhea) return 0; struct nexthop_adata *nhad = (void *) nhea->u.ptr; return NEXTHOP_IS_REACHABLE(nhad) || (nhad->dest != RTD_UNREACHABLE); } extern struct rte_owner_class bgp_rte_owner_class; #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 */ eattr * bgp_find_attr(ea_list *attrs, uint code); void bgp_set_attr_u32(ea_list **to, uint code, uint flags, u32 val); void bgp_set_attr_ptr(ea_list **to, uint code, uint flags, const struct adata *ad); void bgp_set_attr_data(ea_list **to, uint code, uint flags, void *data, uint len); void bgp_unset_attr(ea_list **to, uint code); 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, ea_list **to); void bgp_setup_out_table(struct bgp_channel *c); void bgp_init_pending_tx(struct bgp_channel *c); void bgp_free_pending_tx(struct bgp_channel *c); void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b); int bgp_done_bucket(struct bgp_channel *c, struct bgp_bucket *b); void bgp_done_prefix(struct bgp_channel *c, struct bgp_prefix *px, struct bgp_bucket *buck); int bgp_rte_better(const rte *, const rte *); int bgp_rte_mergable(const rte *pri, const rte *sec); int bgp_rte_recalculate(struct rtable_private *table, net *net, struct rte_storage *new, struct rte_storage *old, struct rte_storage *old_best); void bgp_rte_modify_stale(struct rt_export_request *req, const net_addr *n, struct rt_pending_export *first, struct rt_pending_export *last, const rte **feed, uint count); u32 bgp_rte_igp_metric(const rte *); void bgp_rt_notify(struct proto *P, struct channel *C, const net_addr *n, rte *new, const rte *old); int bgp_preexport(struct channel *, struct rte *); void bgp_get_route_info(const rte *, byte *); int bgp_total_aigp_metric_(const rte *e, u64 *metric, const struct adata **ad); static inline struct bgp_proto *bgp_rte_proto(const rte *rte) { return (rte->src->owner->class == &bgp_rte_owner_class) ? SKIP_BACK(struct bgp_proto, p.sources, rte->src->owner) : NULL; } byte * bgp_bmp_encode_rte(struct bgp_channel *c, byte *buf, const net_addr *n, const struct rte *new, const struct rte_src *src); #define BGP_AIGP_METRIC 1 #define BGP_AIGP_MAX U64(0xffffffffffffffff) static inline u64 bgp_total_aigp_metric(const rte *e) { u64 metric = BGP_AIGP_MAX; const struct adata *ad; bgp_total_aigp_metric_(e, &metric, &ad); return metric; } void bgp_register_attrs(void); struct ea_class *bgp_find_ea_class_by_id(uint id); /* 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); void bgp_uncork(void *vp); 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); byte *bgp_create_end_mark_(struct bgp_channel *c, byte *buf); /* 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 */ enum bgp_attr_id { BA_ORIGIN = 0x01, /* RFC 4271 */ /* WM */ BA_AS_PATH = 0x02, /* WM */ BA_NEXT_HOP = 0x03, /* WM */ BA_MULTI_EXIT_DISC = 0x04, /* ON */ BA_LOCAL_PREF = 0x05, /* WD */ BA_ATOMIC_AGGR = 0x06, /* WD */ BA_AGGREGATOR = 0x07, /* OT */ BA_COMMUNITY = 0x08, /* RFC 1997 */ /* OT */ BA_ORIGINATOR_ID = 0x09, /* RFC 4456 */ /* ON */ BA_CLUSTER_LIST = 0x0a, /* RFC 4456 */ /* ON */ BA_MP_REACH_NLRI = 0x0e, /* RFC 4760 */ BA_MP_UNREACH_NLRI = 0x0f, /* RFC 4760 */ BA_EXT_COMMUNITY = 0x10, /* RFC 4360 */ BA_AS4_PATH = 0x11, /* RFC 6793 */ BA_AS4_AGGREGATOR = 0x12, /* RFC 6793 */ BA_AIGP = 0x1a, /* RFC 7311 */ BA_LARGE_COMMUNITY = 0x20, /* RFC 8092 */ #define BA_ONLY_TO_CUSTOMER 0x23 /* RFC 9234 */ /* Bird's private internal BGP attributes */ BA_MPLS_LABEL_STACK = 0x100, /* MPLS label stack transfer attribute */ /* Maximum */ BGP_ATTR_MAX, }; /* 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