/* * BIRD Internet Routing Daemon -- Routing data structures * * (c) 1998--2000 Martin Mares * (c) 2022 Maria Matejka * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_LIB_ROUTE_H_ #define _BIRD_LIB_ROUTE_H_ #undef RT_SOURCE_DEBUG #undef EA_FREE_DEBUG #include "lib/type.h" #include "lib/rcu.h" #include "lib/hash.h" #include "lib/event.h" #include "lib/lockfree.h" struct network; struct proto; struct cli; struct rtable_private; struct rte_storage; #define RTE_IN_TABLE_WRITABLE \ byte pflags; /* Protocol-specific flags; may change in-table (!) */ \ byte flags; /* Table-specific flags */ \ u8 stale_cycle; /* Auxiliary value for route refresh; may change in-table (!) */ \ typedef struct rte { RTE_IN_TABLE_WRITABLE; u8 generation; /* If this route import is based on other previously exported route, this value should be 1 + MAX(generation of the parent routes). Otherwise the route is independent and this value is zero. */ u32 id; /* Table specific route id */ struct ea_list *attrs; /* Attributes of this route */ const net_addr *net; /* Network this RTE belongs to */ struct rte_src *src; /* Route source that created the route */ struct rt_import_hook *sender; /* Import hook used to send the route to the routing table */ btime lastmod; /* Last modified (set by table) */ } rte; #define REF_FILTERED 2 /* Route is rejected by import filter */ #define REF_OBSOLETE 16 /* Route is obsolete, pending propagation */ #define REF_PENDING 32 /* Route has not propagated completely yet */ /* Route is valid for propagation (may depend on other flags in the future), accepts NULL */ static inline int rte_is_valid(const rte *r) { return r && !(r->flags & REF_FILTERED); } /* Route just has REF_FILTERED flag */ static inline int rte_is_filtered(const rte *r) { return !!(r->flags & REF_FILTERED); } /* Strip the route of the table-specific values */ static inline rte rte_init_from(const rte *r) { return (rte) { .attrs = r->attrs, .net = r->net, .src = r->src, }; } int rte_same(const rte *, const rte *); struct rte_src { struct rte_src *next; /* Hash chain */ struct rte_owner *owner; /* Route source owner */ u64 private_id; /* Private ID, assigned by the protocol */ u32 global_id; /* Globally unique ID of the source */ struct lfuc uc; /* Use count */ }; struct rte_owner_class { void (*get_route_info)(const rte *, byte *buf); /* Get route information (for `show route' command) */ int (*rte_better)(const rte *, const rte *); int (*rte_mergable)(const rte *, const rte *); u32 (*rte_igp_metric)(const rte *); }; struct rte_owner { struct rte_owner_class *class; int (*rte_recalculate)(struct rtable_private *, struct network *, struct rte_storage *new, struct rte_storage *, struct rte_storage *); HASH(struct rte_src) hash; const char *name; u32 hash_key; u32 uc; u32 debug; event_list *list; event *prune; event *stop; }; extern DOMAIN(attrs) attrs_domain; #define RTA_LOCK LOCK_DOMAIN(attrs, attrs_domain) #define RTA_UNLOCK UNLOCK_DOMAIN(attrs, attrs_domain) #define RTE_SRC_PU_SHIFT 44 #define RTE_SRC_IN_PROGRESS (1ULL << RTE_SRC_PU_SHIFT) /* Get a route source. This also locks the source, therefore the caller has to * unlock the source after the route has been propagated. */ struct rte_src *rt_get_source_o(struct rte_owner *o, u32 id); #define rt_get_source(p, id) rt_get_source_o(&(p)->sources, (id)) struct rte_src *rt_find_source_global(u32 id); #ifdef RT_SOURCE_DEBUG #define rt_lock_source _rt_lock_source_internal #define rt_unlock_source _rt_unlock_source_internal #endif static inline void rt_lock_source(struct rte_src *src) { lfuc_lock(&src->uc); } static inline void rt_unlock_source(struct rte_src *src) { lfuc_unlock(&src->uc, src->owner->list, src->owner->prune); } #ifdef RT_SOURCE_DEBUG #undef rt_lock_source #undef rt_unlock_source #define rt_lock_source(x) ( log(L_INFO "Lock source %uG at %s:%d", (x)->global_id, __FILE__, __LINE__), _rt_lock_source_internal(x) ) #define rt_unlock_source(x) ( log(L_INFO "Unlock source %uG at %s:%d", (x)->global_id, __FILE__, __LINE__), _rt_unlock_source_internal(x) ) #endif void rt_init_sources(struct rte_owner *, const char *name, event_list *list); void rt_destroy_sources(struct rte_owner *, event *); void rt_dump_sources(struct rte_owner *); /* * Route Attributes * * Beware: All standard BGP attributes must be represented here instead * of making them local to the route. This is needed to ensure proper * construction of BGP route attribute lists. */ /* Nexthop structure */ struct nexthop { ip_addr gw; /* Next hop */ struct iface *iface; /* Outgoing interface */ byte flags; byte weight; byte labels; /* Number of all labels */ u32 label[0]; }; /* For packing one into eattrs */ struct nexthop_adata { struct adata ad; /* There is either a set of nexthops or a special destination (RTD_*) */ union { struct nexthop nh; uint dest; }; }; /* For MPLS label stack generation */ struct nexthop_adata_mpls { struct nexthop_adata nhad; u32 label_space[MPLS_MAX_LABEL_STACK]; }; #define NEXTHOP_DEST_SIZE (OFFSETOF(struct nexthop_adata, dest) + sizeof(uint) - OFFSETOF(struct adata, data)) #define NEXTHOP_DEST_LITERAL(x) ((struct nexthop_adata) { \ .ad.length = NEXTHOP_DEST_SIZE, .dest = (x), }) #define RNF_ONLINK 0x1 /* Gateway is onlink regardless of IP ranges */ #define RTS_STATIC 1 /* Normal static route */ #define RTS_INHERIT 2 /* Route inherited from kernel */ #define RTS_DEVICE 3 /* Device route */ #define RTS_STATIC_DEVICE 4 /* Static device route */ #define RTS_REDIRECT 5 /* Learned via redirect */ #define RTS_RIP 6 /* RIP route */ #define RTS_OSPF 7 /* OSPF route */ #define RTS_OSPF_IA 8 /* OSPF inter-area route */ #define RTS_OSPF_EXT1 9 /* OSPF external route type 1 */ #define RTS_OSPF_EXT2 10 /* OSPF external route type 2 */ #define RTS_BGP 11 /* BGP route */ #define RTS_PIPE 12 /* Inter-table wormhole */ #define RTS_BABEL 13 /* Babel route */ #define RTS_RPKI 14 /* Route Origin Authorization */ #define RTS_PERF 15 /* Perf checker */ #define RTS_L3VPN 16 /* MPLS L3VPN */ #define RTS_AGGREGATED 17 /* Aggregated route */ #define RTS_MAX 18 #define RTD_NONE 0 /* Undefined next hop */ #define RTD_UNICAST 1 /* A standard next hop */ #define RTD_BLACKHOLE 2 /* Silently drop packets */ #define RTD_UNREACHABLE 3 /* Reject as unreachable */ #define RTD_PROHIBIT 4 /* Administratively prohibited */ #define RTD_MAX 5 extern const char * rta_dest_names[RTD_MAX]; static inline const char *rta_dest_name(uint n) { return (n < RTD_MAX) ? rta_dest_names[n] : "???"; } /* * Extended Route Attributes */ typedef struct eattr { word id; /* EA_CODE(PROTOCOL_..., protocol-dependent ID) */ byte flags; /* Protocol-dependent flags */ byte type; /* Attribute type */ byte rfu:5; byte originated:1; /* The attribute has originated locally */ byte fresh:1; /* An uncached attribute (e.g. modified in export filter) */ byte undef:1; /* Explicitly undefined */ PADDING(unused, 3, 3); union bval u; } eattr; #define EA_CODE_MASK 0xffff #define EA_ALLOW_UNDEF 0x10000 /* ea_find: allow EAF_TYPE_UNDEF */ #define EA_BIT(n) ((n) << 24) /* Used in bitfield accessors */ #define EA_BIT_GET(ea) ((ea) >> 24) typedef struct ea_list { struct ea_list *next; /* In case we have an override list */ byte flags; /* Flags: EALF_... */ byte stored:5; /* enum ea_stored */ byte rfu:3; word count; /* Number of attributes */ eattr attrs[0]; /* Attribute definitions themselves */ } ea_list; enum ea_stored { EALS_NONE = 0, /* This is a temporary ea_list */ EALS_PREIMPORT = 1, /* State when route entered rte_update() */ EALS_FILTERED = 2, /* State after filters */ EALS_IN_TABLE = 3, /* State in table */ EALS_KEY = 4, /* EA list used as key */ EALS_CUSTOM = 0x10, /* OR this with custom values */ EALS_MAX = 0x20, }; struct ea_storage { struct ea_storage *next_hash; /* Next in hash chain */ _Atomic u64 uc; /* Use count */ u32 hash_key; /* List hash */ PADDING(unused, 0, 4); /* Sorry, we need u64 for the usecount */ ea_list l[0]; /* The list itself */ }; #define EALF_SORTED 1 /* Attributes are sorted by code */ #define EALF_BISECT 2 /* Use interval bisection for searching */ #define EALF_HUGE 8 /* List is too big to fit into slab */ struct ea_class { #define EA_CLASS_INSIDE \ const char *name; /* Name (both print and filter) */ \ struct symbol *sym; /* Symbol to export to configs */ \ uint id; /* Autoassigned attribute ID */ \ uint uc; /* Reference count */ \ btype type; /* Data type ID */ \ u16 flags; /* Protocol-dependent flags */ \ uint readonly:1; /* This attribute can't be changed by filters */ \ uint conf:1; /* Requested by config */ \ uint hidden:1; /* Technical attribute, do not show, do not expose to filters */ \ void (*format)(const eattr *ea, byte *buf, uint size); \ void (*stored)(const eattr *ea); /* When stored into global hash */ \ void (*freed)(const eattr *ea); /* When released from global hash */ \ struct f_val (*empty)(const struct ea_class *); /* Return this instead of T_VOID as default value for filters */ \ EA_CLASS_INSIDE; }; struct ea_class_ref { resource r; struct ea_class *class; }; void ea_register_init(struct ea_class *); struct ea_class_ref *ea_register_alloc(pool *, struct ea_class); struct ea_class_ref *ea_ref_class(pool *, struct ea_class *); /* Reference for an attribute alias */ #define EA_REGISTER_ALL_HELPER(x) ea_register_init(x); #define EA_REGISTER_ALL(...) MACRO_FOREACH(EA_REGISTER_ALL_HELPER, __VA_ARGS__) struct ea_class *ea_class_find_by_id(uint id); struct ea_class *ea_class_find_by_name(const char *name); static inline struct ea_class *ea_class_self(struct ea_class *self) { return self; } #define ea_class_find(_arg) _Generic((_arg), \ uint: ea_class_find_by_id, \ word: ea_class_find_by_id, \ char *: ea_class_find_by_name, \ const char *: ea_class_find_by_name, \ struct ea_class *: ea_class_self)(_arg) struct ea_walk_state { ea_list *eattrs; /* Ccurrent ea_list, initially set by caller */ eattr *ea; /* Current eattr, initially NULL */ u32 visited[4]; /* Bitfield, limiting max to 128 */ }; #define ea_find(_l, _arg) _Generic((_arg), uint: ea_find_by_id, struct ea_class *: ea_find_by_class, char *: ea_find_by_name)(_l, _arg) eattr *ea_find_by_id(ea_list *, unsigned ea); static inline eattr *ea_find_by_class(ea_list *l, const struct ea_class *def) { return ea_find_by_id(l, def->id); } static inline eattr *ea_find_by_name(ea_list *l, const char *name) { const struct ea_class *def = ea_class_find_by_name(name); return def ? ea_find_by_class(l, def) : NULL; } #define ea_get_int(_l, _ident, _def) ({ \ struct ea_class *cls = ea_class_find((_ident)); \ ASSERT_DIE(cls->type & EAF_EMBEDDED && cls->type != T_PTR); \ const eattr *ea = ea_find((_l), cls->id); \ (ea ? ea->u.data : (_def)); \ }) #define ea_get_ptr(_l, _ident, _def) ({ \ struct ea_class *cls = ea_class_find((_ident)); \ ASSERT_DIE(cls->type == T_PTR); \ const eattr *ea = ea_find((_l), cls->id); \ (ea ? ea->u.v_ptr : (_def)); \ }) #define ea_get_ip(_l, _ident, _def) ({ \ struct ea_class *cls = ea_class_find((_ident)); \ ASSERT_DIE(cls->type == T_IP); \ const eattr *ea = ea_find((_l), cls->id); \ (ea ? *((const ip_addr *) ea->u.ptr->data) : (_def)); \ }) #define ea_get_adata(_l, _ident) ({ \ struct ea_class *cls = ea_class_find((_ident)); \ ASSERT_DIE(!(cls->type & EAF_EMBEDDED)); \ const eattr *ea = ea_find((_l), cls->id); \ (ea ? ea->u.ptr : &null_adata); \ }) eattr *ea_walk(struct ea_walk_state *s, uint id, uint max); void ea_dump(ea_list *); int ea_same(ea_list *x, ea_list *y); /* Test whether two ea_lists are identical */ uint ea_hash(ea_list *e); /* Calculate attributes hash value */ ea_list *ea_append(ea_list *to, ea_list *what); void ea_format_bitfield(const struct eattr *a, byte *buf, int bufsize, const char **names, int min, int max); /* Normalize ea_list; allocates the result from tmp_linpool */ ea_list *ea_normalize(ea_list *e, u32 upto); uint ea_list_size(ea_list *); void ea_list_copy(ea_list *dest, ea_list *src, uint size); #define EA_LOCAL_LIST(N) struct { ea_list l; eattr a[N]; } #define EA_LITERAL_EMBEDDED(_class, _flags, _val) ({ \ btype _type = (_class)->type; \ ASSERT_DIE(_type & EAF_EMBEDDED && _type != T_PTR); \ EA_LITERAL_GENERIC((_class)->id, _type, _flags, .u.i = _val); \ }) #define EA_LITERAL_STORE_PTR(_class, _flags, _ptr) ({ \ btype _type = (_class)->type; \ ASSERT_DIE(_type == T_PTR); \ EA_LITERAL_GENERIC((_class)->id, _type, _flags, .u.v_ptr = _ptr); \ }) #define EA_LITERAL_STORE_ADATA(_class, _flags, _buf, _len) ({ \ btype _type = (_class)->type; \ ASSERT_DIE(!(_type & EAF_EMBEDDED)); \ EA_LITERAL_GENERIC((_class)->id, _type, _flags, .u.ad = tmp_store_adata((_buf), (_len))); \ }) #define EA_LITERAL_DIRECT_ADATA(_class, _flags, _adata) ({ \ btype _type = (_class)->type; \ ASSERT_DIE(!(_type & EAF_EMBEDDED)); \ EA_LITERAL_GENERIC((_class)->id, _type, _flags, .u.ad = _adata); \ }) #define EA_LITERAL_GENERIC(_id, _type, _flags, ...) \ ((eattr) { .id = _id, .type = _type, .flags = _flags, __VA_ARGS__ }) #define EA_LITERAL_STORE_STRING(_class, _flags, string) ({EA_LITERAL_STORE_ADATA(_class, _flags, string, strlen(string)+1);}) static inline eattr * ea_set_attr(ea_list **to, eattr a) { if (!a.id) bug("You have forgotten to register your EA class"); EA_LOCAL_LIST(1) *ea = tmp_alloc(sizeof(*ea)); *ea = (typeof(*ea)) { .l.flags = EALF_SORTED, .l.count = 1, .l.next = *to, .a[0] = a, }; *to = &ea->l; return &ea->a[0]; } static inline void ea_unset_attr(ea_list **to, bool local, const struct ea_class *def) { ea_set_attr(to, EA_LITERAL_GENERIC(def->id, 0, 0, .fresh = local, .originated = local, .undef = 1)); } static inline void ea_set_attr_u32(ea_list **to, const struct ea_class *def, uint flags, u64 data) { ea_set_attr(to, EA_LITERAL_EMBEDDED(def, flags, data)); } static inline void ea_set_attr_ptr(ea_list **to, const struct ea_class *def, uint flags, void *data) { ea_set_attr(to, EA_LITERAL_STORE_PTR(def, flags, data)); } static inline void ea_set_attr_data(ea_list **to, const struct ea_class *def, uint flags, const void *data, uint len) { ea_set_attr(to, EA_LITERAL_STORE_ADATA(def, flags, data, len)); } static inline void ea_copy_attr(ea_list **to, ea_list *from, const struct ea_class *def) { eattr *e = ea_find_by_class(from, def); if (e) if (e->type == T_PTR) ea_set_attr_ptr(to, def, e->flags, (void *)e->u.v_ptr); else if (e->type & EAF_EMBEDDED) ea_set_attr_u32(to, def, e->flags, e->u.data); else ea_set_attr_data(to, def, e->flags, e->u.ptr->data, e->u.ptr->length); else ea_unset_attr(to, 0, def); } /* * Common route attributes */ /* Preference: first-order comparison */ extern struct ea_class ea_gen_preference; static inline u32 rt_get_preference(const rte *rt) { return ea_get_int(rt->attrs, &ea_gen_preference, 0); } /* IGP metric: second-order comparison */ extern struct ea_class ea_gen_igp_metric; u32 rt_get_igp_metric(const rte *rt); #define IGP_METRIC_UNKNOWN 0x80000000 /* Default igp_metric used when no other protocol-specific metric is availabe */ /* From: Advertising router */ extern struct ea_class ea_gen_from; /* MPLS Label, Policy and Class */ extern struct ea_class ea_gen_mpls_label, ea_gen_mpls_policy, ea_gen_mpls_class; /* Source: An old method to devise the route source protocol and kind. * To be superseded in a near future by something more informative. */ extern struct ea_class ea_gen_source; static inline u32 rt_get_source_attr(const rte *rt) { return ea_get_int(rt->attrs, &ea_gen_source, 0); } /* Flowspec validation result */ enum flowspec_valid { FLOWSPEC_UNKNOWN = 0, FLOWSPEC_VALID = 1, FLOWSPEC_INVALID = 2, FLOWSPEC__MAX, }; extern const char * flowspec_valid_names[FLOWSPEC__MAX]; static inline const char *flowspec_valid_name(enum flowspec_valid v) { return (v < FLOWSPEC__MAX) ? flowspec_valid_names[v] : "???"; } extern struct ea_class ea_gen_flowspec_valid; static inline enum flowspec_valid rt_get_flowspec_valid(const rte *rt) { return ea_get_int(rt->attrs, &ea_gen_flowspec_valid, FLOWSPEC_UNKNOWN); } /* Next hop: For now, stored as adata */ extern struct ea_class ea_gen_nexthop; static inline void ea_set_dest(struct ea_list **to, uint flags, uint dest) { struct nexthop_adata nhad = NEXTHOP_DEST_LITERAL(dest); ea_set_attr_data(to, &ea_gen_nexthop, flags, &nhad.ad.data, nhad.ad.length); } /* Next hop structures */ #define NEXTHOP_ALIGNMENT (_Alignof(struct nexthop)) #define NEXTHOP_MAX_SIZE (sizeof(struct nexthop) + sizeof(u32)*MPLS_MAX_LABEL_STACK) #define NEXTHOP_SIZE(_nh) NEXTHOP_SIZE_CNT(((_nh)->labels)) #define NEXTHOP_SIZE_CNT(cnt) BIRD_ALIGN((sizeof(struct nexthop) + sizeof(u32) * (cnt)), NEXTHOP_ALIGNMENT) #define nexthop_size(nh) NEXTHOP_SIZE((nh)) #define NEXTHOP_NEXT(_nh) ((void *) (_nh) + NEXTHOP_SIZE(_nh)) #define NEXTHOP_END(_nhad) ((_nhad)->ad.data + (_nhad)->ad.length) #define NEXTHOP_VALID(_nh, _nhad) ((void *) (_nh) < (void *) NEXTHOP_END(_nhad)) #define NEXTHOP_ONE(_nhad) (NEXTHOP_NEXT(&(_nhad)->nh) == NEXTHOP_END(_nhad)) #define NEXTHOP_WALK(_iter, _nhad) for ( \ struct nexthop *_iter = &(_nhad)->nh; \ (void *) _iter < (void *) NEXTHOP_END(_nhad); \ _iter = NEXTHOP_NEXT(_iter)) static inline int nexthop_same(struct nexthop_adata *x, struct nexthop_adata *y) { return adata_same(&x->ad, &y->ad); } struct nexthop_adata *nexthop_merge(struct nexthop_adata *x, struct nexthop_adata *y, int max, linpool *lp); struct nexthop_adata *nexthop_sort(struct nexthop_adata *x, linpool *lp); int nexthop_is_sorted(struct nexthop_adata *x); #define NEXTHOP_IS_REACHABLE(nhad) ((nhad)->ad.length > NEXTHOP_DEST_SIZE) static inline struct nexthop_adata * rte_get_nexthops(rte *r) { eattr *nhea = ea_find(r->attrs, &ea_gen_nexthop); return nhea ? SKIP_BACK(struct nexthop_adata, ad, nhea->u.ptr) : NULL; } /* Route has regular, reachable nexthop (i.e. not RTD_UNREACHABLE and like) */ static inline int rte_is_reachable(rte *r) { struct nexthop_adata *nhad = rte_get_nexthops(r); return nhad && NEXTHOP_IS_REACHABLE(nhad); } static inline int nhea_dest(eattr *nhea) { if (!nhea) return RTD_NONE; struct nexthop_adata *nhad = nhea ? (struct nexthop_adata *) nhea->u.ptr : NULL; if (NEXTHOP_IS_REACHABLE(nhad)) return RTD_UNICAST; else return nhad->dest; } static inline int rte_dest(const rte *r) { return nhea_dest(ea_find(r->attrs, &ea_gen_nexthop)); } /* ASPA Providers eattr */ extern struct ea_class ea_gen_aspa_providers; void rta_init(void); ea_list *ea_lookup_slow(ea_list *r, u32 squash_upto, enum ea_stored oid); static inline struct ea_storage *ea_get_storage(ea_list *r) { ASSERT_DIE(r->stored); return SKIP_BACK(struct ea_storage, l[0], r); } static inline ea_list *ea_ref(ea_list *r) { ASSERT_DIE(0 < atomic_fetch_add_explicit(&ea_get_storage(r)->uc, 1, memory_order_acq_rel)); return r; } static inline ea_list *ea_lookup(ea_list *r, u32 squash_upto, enum ea_stored oid) { ASSERT_DIE(oid); if ((r->stored == oid) || BIT32_TEST(&squash_upto, r->stored)) return ea_ref(r); else return ea_lookup_slow(r, squash_upto, oid); } struct ea_free_deferred { struct deferred_call dc; ea_list *attrs; }; void ea_free_deferred(struct deferred_call *dc); #ifdef EA_FREE_DEBUG #define ea_free_later _ea_free_later_internal #endif static inline ea_list *ea_free_later(ea_list *r) { if (!r) return NULL; struct ea_free_deferred efd = { .dc.hook = ea_free_deferred, .attrs = r, }; defer_call(&efd.dc, sizeof efd); return r; } #ifdef EA_FREE_DEBUG #undef ea_free_later #define ea_free_later(x) ( log(L_INFO "EA free request %p at %s:%d", (x), __FILE__, __LINE__), _ea_free_later_internal(x) ) #endif #define ea_free ea_free_later static inline ea_list *ea_lookup_tmp(ea_list *r, u32 squash_upto, enum ea_stored oid) { return ea_free_later(ea_lookup(r, squash_upto, oid)); } static inline ea_list *ea_ref_tmp(ea_list *r) { ASSERT_DIE(r->stored); return ea_free_later(ea_ref(r)); } static inline ea_list *ea_strip_to(ea_list *r, u32 strip_to) { ASSERT_DIE(strip_to); while (r && !BIT32_TEST(&strip_to, r->stored)) r = r->next; return r; } void ea_dump(ea_list *); void ea_dump_all(void); void ea_show_list(struct cli *, ea_list *); #endif