/* * BIRD Internet Routing Daemon -- Routing Table * * (c) 1998--2000 Martin Mares * (c) 2019--2021 Maria Matejka * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_NEST_RT_H_ #define _BIRD_NEST_RT_H_ #include "lib/lists.h" #include "lib/bitmap.h" #include "lib/resource.h" #include "lib/net.h" #include "lib/type.h" #include "lib/fib.h" #include "lib/route.h" struct ea_list; struct protocol; struct proto; struct channel; struct rte_src; struct symbol; struct timer; struct filter; struct f_trie; struct f_trie_walk_state; struct cli; /* * Master Routing Tables. Generally speaking, each of them contains a FIB * with each entry pointing to a list of route entries representing routes * to given network (with the selected one at the head). * * Each of the RTE's contains variable data (the preference and protocol-dependent * metrics) and a pointer to a route attribute block common for many routes). * * It's guaranteed that there is at most one RTE for every (prefix,proto) pair. */ struct rtable_config { node n; char *name; struct rtable *table; struct proto_config *krt_attached; /* Kernel syncer attached to this table */ uint addr_type; /* Type of address data stored in table (NET_*) */ int gc_max_ops; /* Maximum number of operations before GC is run */ int gc_min_time; /* Minimum time between two consecutive GC runs */ byte sorted; /* Routes of network are sorted according to rte_better() */ byte internal; /* Internal table of a protocol */ byte trie_used; /* Rtable has attached trie */ btime min_settle_time; /* Minimum settle time for notifications */ btime max_settle_time; /* Maximum settle time for notifications */ }; typedef struct rtable { resource r; node n; /* Node in list of all tables */ pool *rp; /* Resource pool to allocate everything from, including itself */ struct slab *rte_slab; /* Slab to allocate route objects */ struct fib fib; struct f_trie *trie; /* Trie of prefixes defined in fib */ char *name; /* Name of this table */ uint addr_type; /* Type of address data stored in table (NET_*) */ int use_count; /* Number of protocols using this table */ u32 rt_count; /* Number of routes in the table */ list imports; /* Registered route importers */ list exports; /* Registered route exporters */ struct hmap id_map; struct hostcache *hostcache; struct rtable_config *config; /* Configuration of this table */ struct config *deleted; /* Table doesn't exist in current configuration, * delete as soon as use_count becomes 0 and remove * obstacle from this routing table. */ struct event *rt_event; /* Routing table event */ btime last_rt_change; /* Last time when route changed */ btime base_settle_time; /* Start time of rtable settling interval */ btime gc_time; /* Time of last GC */ int gc_counter; /* Number of operations since last GC */ byte prune_state; /* Table prune state, 1 -> scheduled, 2-> running */ byte prune_trie; /* Prune prefix trie during next table prune */ byte hcu_scheduled; /* Hostcache update is scheduled */ byte nhu_state; /* Next Hop Update state */ byte internal; /* This table is internal for some other object */ struct fib_iterator prune_fit; /* Rtable prune FIB iterator */ struct fib_iterator nhu_fit; /* Next Hop Update FIB iterator */ struct f_trie *trie_new; /* New prefix trie defined during pruning */ struct f_trie *trie_old; /* Old prefix trie waiting to be freed */ u32 trie_lock_count; /* Prefix trie locked by walks */ u32 trie_old_lock_count; /* Old prefix trie locked by walks */ struct tbf rl_pipe; /* Rate limiting token buffer for pipe collisions */ list subscribers; /* Subscribers for notifications */ struct timer *settle_timer; /* Settle time for notifications */ list flowspec_links; /* List of flowspec links, src for NET_IPx and dst for NET_FLOWx */ struct f_trie *flowspec_trie; /* Trie for evaluation of flowspec notifications */ } rtable; struct rt_subscription { node n; rtable *tab; void (*hook)(struct rt_subscription *b); void *data; }; struct rt_flowspec_link { node n; rtable *src; rtable *dst; u32 uc; }; #define NHU_CLEAN 0 #define NHU_SCHEDULED 1 #define NHU_RUNNING 2 #define NHU_DIRTY 3 typedef struct network { struct rte_storage *routes; /* Available routes for this network */ struct fib_node n; /* FIB flags reserved for kernel syncer */ } net; struct hostcache { slab *slab; /* Slab holding all hostentries */ struct hostentry **hash_table; /* Hash table for hostentries */ unsigned hash_order, hash_shift; unsigned hash_max, hash_min; unsigned hash_items; linpool *lp; /* Linpool for trie */ struct f_trie *trie; /* Trie of prefixes that might affect hostentries */ list hostentries; /* List of all hostentries */ byte update_hostcache; }; struct hostentry { node ln; ip_addr addr; /* IP address of host, part of key */ ip_addr link; /* (link-local) IP address of host, used as gw if host is directly attached */ struct rtable *tab; /* Dependent table, part of key */ struct hostentry *next; /* Next in hash chain */ unsigned hash_key; /* Hash key */ unsigned uc; /* Use count */ struct rta *src; /* Source rta entry */ byte dest; /* Chosen route destination type (RTD_...) */ byte nexthop_linkable; /* Nexthop list is completely non-device */ u32 igp_metric; /* Chosen route IGP metric */ }; struct rte_storage { struct rte_storage *next; /* Next in chain */ struct rte rte; /* Route data */ }; #define RTE_COPY(r, l) ((r) ? (((*(l)) = (r)->rte), (l)) : NULL) #define RTE_OR_NULL(r) ((r) ? &((r)->rte) : NULL) /* Table-channel connections */ struct rt_import_request { struct rt_import_hook *hook; /* The table part of importer */ char *name; u8 trace_routes; void (*dump_req)(struct rt_import_request *req); void (*log_state_change)(struct rt_import_request *req, u8 state); /* Preimport is called when the @new route is just-to-be inserted, replacing @old. * Return a route (may be different or modified in-place) to continue or NULL to withdraw. */ struct rte *(*preimport)(struct rt_import_request *req, struct rte *new, struct rte *old); struct rte *(*rte_modify)(struct rte *, struct linpool *); }; struct rt_import_hook { node n; rtable *table; /* The connected table */ struct rt_import_request *req; /* The requestor */ struct rt_import_stats { /* Import - from protocol to core */ u32 pref; /* Number of routes selected as best in the (adjacent) routing table */ u32 updates_ignored; /* Number of route updates rejected as already in route table */ u32 updates_accepted; /* Number of route updates accepted and imported */ u32 withdraws_ignored; /* Number of route withdraws rejected as already not in route table */ u32 withdraws_accepted; /* Number of route withdraws accepted and processed */ } stats; btime last_state_change; /* Time of last state transition */ u8 import_state; /* IS_* */ void (*stopped)(struct rt_import_request *); /* Stored callback when import is stopped */ }; struct rt_pending_export { struct rte_storage *new, *new_best, *old, *old_best; }; struct rt_export_request { struct rt_export_hook *hook; /* Table part of the export */ char *name; u8 trace_routes; /* There are two methods of export. You can either request feeding every single change * or feeding the whole route feed. In case of regular export, &export_one is preferred. * Anyway, when feeding, &export_bulk is preferred, falling back to &export_one. * Thus, for RA_OPTIMAL, &export_one is only set, * for RA_MERGED and RA_ACCEPTED, &export_bulk is only set * and for RA_ANY, both are set to accomodate for feeding all routes but receiving single changes */ void (*export_one)(struct rt_export_request *req, const net_addr *net, struct rt_pending_export *rpe); void (*export_bulk)(struct rt_export_request *req, const net_addr *net, struct rt_pending_export *rpe, rte **feed, uint count); void (*dump_req)(struct rt_export_request *req); void (*log_state_change)(struct rt_export_request *req, u8); }; struct rt_export_hook { node n; rtable *table; /* The connected table */ pool *pool; linpool *lp; struct rt_export_request *req; /* The requestor */ struct rt_export_stats { /* Export - from core to protocol */ u32 updates_received; /* Number of route updates received */ u32 withdraws_received; /* Number of route withdraws received */ } stats; struct fib_iterator feed_fit; /* Routing table iterator used during feeding */ btime last_state_change; /* Time of last state transition */ u8 refeed_pending; /* Refeeding and another refeed is scheduled */ u8 export_state; /* Route export state (TES_*, see below) */ struct event *event; /* Event running all the export operations */ void (*stopped)(struct rt_export_request *); /* Stored callback when export is stopped */ }; #define TIS_DOWN 0 #define TIS_UP 1 #define TIS_STOP 2 #define TIS_FLUSHING 3 #define TIS_WAITING 4 #define TIS_CLEARED 5 #define TIS_MAX 6 #define TES_DOWN 0 #define TES_HUNGRY 1 #define TES_FEEDING 2 #define TES_READY 3 #define TES_STOP 4 #define TES_MAX 5 void rt_request_import(rtable *tab, struct rt_import_request *req); void rt_request_export(rtable *tab, struct rt_export_request *req); void rt_stop_import(struct rt_import_request *, void (*stopped)(struct rt_import_request *)); void rt_stop_export(struct rt_export_request *, void (*stopped)(struct rt_export_request *)); const char *rt_import_state_name(u8 state); const char *rt_export_state_name(u8 state); static inline u8 rt_import_get_state(struct rt_import_hook *ih) { return ih ? ih->import_state : TIS_DOWN; } static inline u8 rt_export_get_state(struct rt_export_hook *eh) { return eh ? eh->export_state : TES_DOWN; } void rte_import(struct rt_import_request *req, const net_addr *net, rte *new, struct rte_src *src); /* Types of route announcement, also used as flags */ #define RA_UNDEF 0 /* Undefined RA type */ #define RA_OPTIMAL 1 /* Announcement of optimal route change */ #define RA_ACCEPTED 2 /* Announcement of first accepted route */ #define RA_ANY 3 /* Announcement of any route change */ #define RA_MERGED 4 /* Announcement of optimal route merged with next ones */ /* Return value of preexport() callback */ #define RIC_ACCEPT 1 /* Accepted by protocol */ #define RIC_PROCESS 0 /* Process it through import filter */ #define RIC_REJECT -1 /* Rejected by protocol */ #define RIC_DROP -2 /* Silently dropped by protocol */ #define rte_update channel_rte_import /** * rte_update - enter a new update to a routing table * @c: channel doing the update * @net: network address * @rte: a &rte representing the new route * @src: old route source identifier * * This function imports a new route to the appropriate table (via the channel). * Table keys are @net (obligatory) and @rte->attrs->src. * Both the @net and @rte pointers can be local. * * The route attributes (@rte->attrs) are obligatory. They can be also allocated * locally. Anyway, if you use an already-cached attribute object, you shall * call rta_clone() on that object yourself. (This semantics may change in future.) * * If the route attributes are local, you may set @rte->attrs->src to NULL, then * the protocol's default route source will be supplied. * * When rte_update() gets a route, it automatically validates it. This includes * checking for validity of the given network and next hop addresses and also * checking for host-scope or link-scope routes. Then the import filters are * processed and if accepted, the route is passed to route table recalculation. * * The accepted routes are then inserted into the table, replacing the old route * for the same @net identified by @src. Then the route is announced * to all the channels connected to the table using the standard export mechanism. * Setting @rte to NULL makes this a withdraw, otherwise @rte->src must be the same * as @src. * * All memory used for temporary allocations is taken from a special linpool * @rte_update_pool and freed when rte_update() finishes. */ void rte_update(struct channel *c, const net_addr *net, struct rte *rte, struct rte_src *src); extern list routing_tables; struct config; void rt_init(void); void rt_preconfig(struct config *); void rt_commit(struct config *new, struct config *old); void rt_lock_table(rtable *); void rt_unlock_table(rtable *); struct f_trie * rt_lock_trie(rtable *tab); void rt_unlock_trie(rtable *tab, struct f_trie *trie); void rt_subscribe(rtable *tab, struct rt_subscription *s); void rt_unsubscribe(struct rt_subscription *s); void rt_flowspec_link(rtable *src, rtable *dst); void rt_flowspec_unlink(rtable *src, rtable *dst); rtable *rt_setup(pool *, struct rtable_config *); static inline void rt_shutdown(rtable *r) { rfree(r->rp); } static inline net *net_find(rtable *tab, const net_addr *addr) { return (net *) fib_find(&tab->fib, addr); } static inline net *net_find_valid(rtable *tab, const net_addr *addr) { net *n = net_find(tab, addr); return (n && n->routes && rte_is_valid(&n->routes->rte)) ? n : NULL; } static inline net *net_get(rtable *tab, const net_addr *addr) { return (net *) fib_get(&tab->fib, addr); } net *net_get(rtable *tab, const net_addr *addr); net *net_route(rtable *tab, const net_addr *n); int rt_examine(rtable *t, net_addr *a, struct channel *c, const struct filter *filter); rte *rt_export_merged(struct channel *c, rte ** feed, uint count, linpool *pool, int silent); void rt_refresh_begin(rtable *t, struct rt_import_request *); void rt_refresh_end(rtable *t, struct rt_import_request *); void rt_modify_stale(rtable *t, struct rt_import_request *); void rt_schedule_prune(rtable *t); void rte_dump(struct rte_storage *); void rte_free(struct rte_storage *); struct rte_storage *rte_store(const rte *, net *net, rtable *); void rt_dump(rtable *); void rt_dump_all(void); void rt_dump_hooks(rtable *); void rt_dump_hooks_all(void); int rt_reload_channel(struct channel *c); void rt_reload_channel_abort(struct channel *c); void rt_refeed_channel(struct channel *c); void rt_prune_sync(rtable *t, int all); int rte_update_in(struct channel *c, const net_addr *n, rte *new, struct rte_src *src); int rte_update_out(struct channel *c, const net_addr *n, rte *new, const rte *old, struct rte_storage **old_exported); struct rtable_config *rt_new_table(struct symbol *s, uint addr_type); static inline int rt_is_ip(rtable *tab) { return (tab->addr_type == NET_IP4) || (tab->addr_type == NET_IP6); } static inline int rt_is_vpn(rtable *tab) { return (tab->addr_type == NET_VPN4) || (tab->addr_type == NET_VPN6); } static inline int rt_is_roa(rtable *tab) { return (tab->addr_type == NET_ROA4) || (tab->addr_type == NET_ROA6); } static inline int rt_is_flow(rtable *tab) { return (tab->addr_type == NET_FLOW4) || (tab->addr_type == NET_FLOW6); } /* Default limit for ECMP next hops, defined in sysdep code */ extern const int rt_default_ecmp; struct rt_show_data_rtable { node n; rtable *table; struct channel *export_channel; }; struct rt_show_data { net_addr *addr; list tables; struct rt_show_data_rtable *tab; /* Iterator over table list */ struct rt_show_data_rtable *last_table; /* Last table in output */ struct fib_iterator fit; /* Iterator over networks in table */ struct f_trie_walk_state *walk_state; /* Iterator over networks in trie */ struct f_trie *walk_lock; /* Locked trie for walking */ int verbose, tables_defined_by; const struct filter *filter; struct proto *show_protocol; struct proto *export_protocol; struct channel *export_channel; struct config *running_on_config; struct krt_proto *kernel; struct rt_export_hook *kernel_export_hook; int export_mode, addr_mode, primary_only, filtered, stats; int table_open; /* Iteration (fit) is open */ int trie_walk; /* Current table is iterated using trie */ int net_counter, rt_counter, show_counter, table_counter; int net_counter_last, rt_counter_last, show_counter_last; }; void rt_show(struct rt_show_data *); struct rt_show_data_rtable * rt_show_add_table(struct rt_show_data *d, rtable *t); /* Value of table definition mode in struct rt_show_data */ #define RSD_TDB_DEFAULT 0 /* no table specified */ #define RSD_TDB_INDIRECT 0 /* show route ... protocol P ... */ #define RSD_TDB_ALL RSD_TDB_SET /* show route ... table all ... */ #define RSD_TDB_DIRECT RSD_TDB_SET | RSD_TDB_NMN /* show route ... table X table Y ... */ #define RSD_TDB_SET 0x1 /* internal: show empty tables */ #define RSD_TDB_NMN 0x2 /* internal: need matching net */ /* Value of addr_mode */ #define RSD_ADDR_EQUAL 1 /* Exact query - show route */ #define RSD_ADDR_FOR 2 /* Longest prefix match - show route for */ #define RSD_ADDR_IN 3 /* Interval query - show route in */ /* Value of export_mode in struct rt_show_data */ #define RSEM_NONE 0 /* Export mode not used */ #define RSEM_PREEXPORT 1 /* Routes ready for export, before filtering */ #define RSEM_EXPORT 2 /* Routes accepted by export filter */ #define RSEM_NOEXPORT 3 /* Routes rejected by export filter */ #define RSEM_EXPORTED 4 /* Routes marked in export map */ struct hostentry * rt_get_hostentry(rtable *tab, ip_addr a, ip_addr ll, rtable *dep); void rta_apply_hostentry(rta *a, struct hostentry *he, mpls_label_stack *mls); static inline void rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr gw, ip_addr ll, mpls_label_stack *mls) { rta_apply_hostentry(a, rt_get_hostentry(tab, gw, ll, dep), mls); } /* * rta_set_recursive_next_hop() acquires hostentry from hostcache and fills * rta->hostentry field. New hostentry has zero use count. Cached rta locks its * hostentry (increases its use count), uncached rta does not lock it. Hostentry * with zero use count is removed asynchronously during host cache update, * therefore it is safe to hold such hostentry temorarily. Hostentry holds a * lock for a 'source' rta, mainly to share multipath nexthops. * * There is no need to hold a lock for hostentry->dep table, because that table * contains routes responsible for that hostentry, and therefore is non-empty if * given hostentry has non-zero use count. If the hostentry has zero use count, * the entry is removed before dep is referenced. * * The protocol responsible for routes with recursive next hops should hold a * lock for a 'source' table governing that routes (argument tab to * rta_set_recursive_next_hop()), because its routes reference hostentries * (through rta) related to the governing table. When all such routes are * removed, rtas are immediately removed achieving zero uc. Then the 'source' * table lock could be immediately released, although hostentries may still * exist - they will be freed together with the 'source' table. */ static inline void rt_lock_hostentry(struct hostentry *he) { if (he) he->uc++; } static inline void rt_unlock_hostentry(struct hostentry *he) { if (he) he->uc--; } int rt_flowspec_check(rtable *tab_ip, rtable *tab_flow, const net_addr *n, rta *a, int interior); /* * Default protocol preferences */ #define DEF_PREF_DIRECT 240 /* Directly connected */ #define DEF_PREF_STATIC 200 /* Static route */ #define DEF_PREF_OSPF 150 /* OSPF intra-area, inter-area and type 1 external routes */ #define DEF_PREF_BABEL 130 /* Babel */ #define DEF_PREF_RIP 120 /* RIP */ #define DEF_PREF_BGP 100 /* BGP */ #define DEF_PREF_RPKI 100 /* RPKI */ #define DEF_PREF_INHERITED 10 /* Routes inherited from other routing daemons */ #define DEF_PREF_UNKNOWN 0 /* Routes with no preference set */ /* * Route Origin Authorization */ #define ROA_UNKNOWN 0 #define ROA_VALID 1 #define ROA_INVALID 2 int net_roa_check(rtable *tab, const net_addr *n, u32 asn); #endif