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/*
* BIRD Internet Routing Daemon -- Routing Table
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
* (c) 2019--2021 Maria Matejka <mq@jmq.cz>
*
* 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 <addr> */
#define RSD_ADDR_FOR 2 /* Longest prefix match - show route for <addr> */
#define RSD_ADDR_IN 3 /* Interval query - show route in <addr> */
/* 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
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