/* * BIRD Internet Routing Daemon -- Routing Table * * (c) 1998--2000 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_ROUTE_H_ #define _BIRD_ROUTE_H_ #include "lib/lists.h" #include "lib/resource.h" #include "lib/timer.h" struct protocol; struct proto; struct symbol; struct filter; struct cli; /* * Generic data structure for storing network prefixes. Also used * for the master routing table. Currently implemented as a hash * table. * * Available operations: * - insertion of new entry * - deletion of entry * - searching for entry by network prefix * - asynchronous retrieval of fib contents */ struct fib_node { struct fib_node *next; /* Next in hash chain */ struct fib_iterator *readers; /* List of readers of this node */ byte pxlen; byte flags; /* User-defined */ byte x0, x1; /* User-defined */ ip_addr prefix; /* In host order */ }; struct fib_iterator { /* See lib/slists.h for an explanation */ struct fib_iterator *prev, *next; /* Must be synced with struct fib_node! */ byte efef; /* 0xff to distinguish between iterator and node */ byte pad[3]; struct fib_node *node; /* Or NULL if freshly merged */ unsigned int hash; }; typedef void (*fib_init_func)(struct fib_node *); struct fib { pool *fib_pool; /* Pool holding all our data */ slab *fib_slab; /* Slab holding all fib nodes */ struct fib_node **hash_table; /* Node hash table */ unsigned int hash_size; /* Number of hash table entries (a power of two) */ unsigned int hash_order; /* Binary logarithm of hash_size */ unsigned int hash_shift; /* 16 - hash_log */ unsigned int entries; /* Number of entries */ unsigned int entries_min, entries_max;/* Entry count limits (else start rehashing) */ fib_init_func init; /* Constructor */ }; void fib_init(struct fib *, pool *, unsigned node_size, unsigned hash_order, fib_init_func init); void *fib_find(struct fib *, ip_addr *, int); /* Find or return NULL if doesn't exist */ void *fib_get(struct fib *, ip_addr *, int); /* Find or create new if nonexistent */ void *fib_route(struct fib *, ip_addr, int); /* Longest-match routing lookup */ void fib_delete(struct fib *, void *); /* Remove fib entry */ void fib_free(struct fib *); /* Destroy the fib */ void fib_check(struct fib *); /* Consistency check for debugging */ void fit_init(struct fib_iterator *, struct fib *); /* Internal functions, don't call */ struct fib_node *fit_get(struct fib *, struct fib_iterator *); void fit_put(struct fib_iterator *, struct fib_node *); #define FIB_WALK(fib, z) do { \ struct fib_node *z, **ff = (fib)->hash_table; \ unsigned int count = (fib)->hash_size; \ while (count--) \ for(z = *ff++; z; z=z->next) #define FIB_WALK_END } while (0) #define FIB_ITERATE_INIT(it, fib) fit_init(it, fib) #define FIB_ITERATE_START(fib, it, z) do { \ struct fib_node *z = fit_get(fib, it); \ unsigned int count = (fib)->hash_size; \ unsigned int hpos = (it)->hash; \ for(;;) { \ if (!z) \ { \ if (++hpos >= count) \ break; \ z = (fib)->hash_table[hpos]; \ continue; \ } #define FIB_ITERATE_END(z) z = z->next; } } while(0) #define FIB_ITERATE_PUT(it, z) fit_put(it, z) /* * 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 */ int gc_max_ops; /* Maximum number of operations before GC is run */ int gc_min_time; /* Minimum time between two consecutive GC runs */ }; typedef struct rtable { node n; /* Node in list of all tables */ struct fib fib; char *name; /* Name of this table */ list hooks; /* List of announcement hooks */ int pipe_busy; /* Pipe loop detection */ int use_count; /* Number of protocols using this table */ 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 *gc_event; /* Garbage collector event */ int gc_counter; /* Number of operations since last GC */ bird_clock_t gc_time; /* Time of last GC */ } rtable; typedef struct network { struct fib_node n; /* FIB flags reserved for kernel syncer */ struct rte *routes; /* Available routes for this network */ } net; typedef struct rte { struct rte *next; net *net; /* Network this RTE belongs to */ struct rta *attrs; /* Attributes of this route */ byte flags; /* Flags (REF_...) */ byte pflags; /* Protocol-specific flags */ word pref; /* Route preference */ bird_clock_t lastmod; /* Last modified */ union { /* Protocol-dependent data (metrics etc.) */ #ifdef CONFIG_RIP struct { node garbage; /* List for garbage collection */ byte metric; /* RIP metric */ u16 tag; /* External route tag */ struct rip_entry *entry; } rip; #endif #ifdef CONFIG_OSPF struct { u32 metric1, metric2; /* OSPF Type 1 and Type 2 metrics */ u32 tag; /* External route tag */ } ospf; #endif struct { /* Routes generated by krt sync (both temporary and inherited ones) */ s8 src; /* Alleged route source (see krt.h) */ u8 proto; /* Kernel source protocol ID */ u8 type; /* Kernel route type */ u8 seen; /* Seen during last scan */ u32 metric; /* Kernel metric */ } krt; } u; } rte; #define REF_COW 1 /* Copy this rte on write */ 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 *); void rt_setup(pool *, rtable *, char *, struct rtable_config *); static inline net *net_find(rtable *tab, ip_addr addr, unsigned len) { return (net *) fib_find(&tab->fib, &addr, len); } static inline net *net_get(rtable *tab, ip_addr addr, unsigned len) { return (net *) fib_get(&tab->fib, &addr, len); } rte *rte_find(net *net, struct proto *p); rte *rte_get_temp(struct rta *); void rte_update(rtable *tab, net *net, struct proto *p, rte *new); void rte_discard(rtable *tab, rte *old); void rte_dump(rte *); void rte_free(rte *); rte *rte_do_cow(rte *); static inline rte * rte_cow(rte *r) { return (r->flags & REF_COW) ? rte_do_cow(r) : r; } void rt_dump(rtable *); void rt_dump_all(void); int rt_feed_baby(struct proto *p); void rt_feed_baby_abort(struct proto *p); void rt_prune(rtable *tab); void rt_prune_all(void); struct rtable_config *rt_new_table(struct symbol *s); struct rt_show_data { ip_addr prefix; unsigned pxlen; rtable *table; struct filter *filter; int verbose; struct fib_iterator fit; struct proto *import_protocol; int import_mode, primary_only; struct config *running_on_config; int net_counter, rt_counter, show_counter; int stats, show_for; }; void rt_show(struct rt_show_data *); /* * 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. */ typedef struct rta { struct rta *next, **pprev; /* Hash chain */ struct proto *proto; /* Protocol instance */ unsigned uc; /* Use count */ byte source; /* Route source (RTS_...) */ byte scope; /* Route scope (SCOPE_... -- see ip.h) */ byte cast; /* Casting type (RTC_...) */ byte dest; /* Route destination type (RTD_...) */ byte flags; /* Route flags (RTF_...), now unused */ byte aflags; /* Attribute cache flags (RTAF_...) */ u16 hash_key; /* Hash over important fields */ ip_addr gw; /* Next hop */ ip_addr from; /* Advertising router */ struct iface *iface; /* Outgoing interface */ struct ea_list *eattrs; /* Extended Attribute chain */ } rta; #define RTS_DUMMY 0 /* Dummy route to be removed soon */ #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_EXT 9 /* OSPF external route */ #define RTS_BGP 10 /* BGP route */ #define RTS_PIPE 11 /* Inter-table wormhole */ #define RTC_UNICAST 0 #define RTC_BROADCAST 1 #define RTC_MULTICAST 2 #define RTC_ANYCAST 3 /* IPv6 Anycast */ #define RTD_ROUTER 0 /* Next hop is neighbor router */ #define RTD_DEVICE 1 /* Points to device */ #define RTD_BLACKHOLE 2 /* Silently drop packets */ #define RTD_UNREACHABLE 3 /* Reject as unreachable */ #define RTD_PROHIBIT 4 /* Administratively prohibited */ #define RTD_NONE 5 /* Invalid RTD */ #define RTAF_CACHED 1 /* This is a cached rta */ /* * Extended Route Attributes */ typedef struct eattr { word id; /* EA_CODE(EAP_..., protocol-dependent ID) */ byte flags; /* Protocol-dependent flags */ byte type; /* Attribute type and several flags (EAF_...) */ union { u32 data; struct adata *ptr; /* Attribute data elsewhere */ } u; } eattr; #define EAP_GENERIC 0 /* Generic attributes */ #define EAP_BGP 1 /* BGP attributes */ #define EAP_RIP 2 /* RIP */ #define EAP_OSPF 3 /* OSPF */ #define EAP_MAX 4 #define EA_CODE(proto,id) (((proto) << 8) | (id)) #define EA_PROTO(ea) ((ea) >> 8) #define EA_ID(ea) ((ea) & 0xff) #define EA_CODE_MASK 0xffff #define EA_ALLOW_UNDEF 0x10000 /* ea_find: allow EAF_TYPE_UNDEF */ #define EAF_TYPE_MASK 0x0f /* Mask with this to get type */ #define EAF_TYPE_INT 0x01 /* 32-bit signed integer number */ #define EAF_TYPE_OPAQUE 0x02 /* Opaque byte string (not filterable) */ #define EAF_TYPE_IP_ADDRESS 0x04 /* IP address */ #define EAF_TYPE_ROUTER_ID 0x05 /* Router ID (IPv4 address) */ #define EAF_TYPE_AS_PATH 0x06 /* BGP AS path (encoding per RFC 1771:4.3) */ #define EAF_TYPE_INT_SET 0x0a /* Set of u32's (e.g., a community list) */ #define EAF_TYPE_UNDEF 0x0f /* `force undefined' entry */ #define EAF_EMBEDDED 0x01 /* Data stored in eattr.u.data (part of type spec) */ #define EAF_VAR_LENGTH 0x02 /* Attribute length is variable (part of type spec) */ #define EAF_ORIGINATED 0x40 /* The attribute has originated locally */ #define EAF_TEMP 0x80 /* A temporary attribute (the one stored in the tmp attr list) */ struct adata { unsigned int length; /* Length of data */ byte data[0]; }; typedef struct ea_list { struct ea_list *next; /* In case we have an override list */ byte flags; /* Flags: EALF_... */ byte rfu; word count; /* Number of attributes */ eattr attrs[0]; /* Attribute definitions themselves */ } ea_list; #define EALF_SORTED 1 /* Attributes are sorted by code */ #define EALF_BISECT 2 /* Use interval bisection for searching */ #define EALF_CACHED 4 /* Attributes belonging to cached rta */ eattr *ea_find(ea_list *, unsigned ea); int ea_get_int(ea_list *, unsigned ea, int def); void ea_dump(ea_list *); void ea_sort(ea_list *); /* Sort entries in all sub-lists */ unsigned ea_scan(ea_list *); /* How many bytes do we need for merged ea_list */ void ea_merge(ea_list *from, ea_list *to); /* Merge sub-lists to allocated buffer */ int ea_same(ea_list *x, ea_list *y); /* Test whether two ea_lists are identical */ unsigned int ea_hash(ea_list *e); /* Calculate 16-bit hash value */ void ea_format(eattr *e, byte *buf); #define EA_FORMAT_BUF_SIZE 256 ea_list *ea_append(ea_list *to, ea_list *what); void rta_init(void); rta *rta_lookup(rta *); /* Get rta equivalent to this one, uc++ */ static inline rta *rta_clone(rta *r) { r->uc++; return r; } void rta__free(rta *r); static inline void rta_free(rta *r) { if (r && !--r->uc) rta__free(r); } void rta_dump(rta *); void rta_dump_all(void); void rta_show(struct cli *, rta *, ea_list *); extern struct protocol *attr_class_to_protocol[EAP_MAX]; /* * 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_RIP 120 /* RIP */ #define DEF_PREF_BGP 100 /* BGP */ #define DEF_PREF_PIPE 70 /* Routes piped from other tables */ #define DEF_PREF_INHERITED 10 /* Routes inherited from other routing daemons */ #endif