Merge commit 'ef6a903e6f44b467f9606018446095521ad01ef1' into haugesund

1 files changed, 501 insertions, 0 deletions

diff --git a/nest/rt.h b/nest/rt.h
new file mode 100644
index 00000000..f7a351b2
--- /dev/null
+++ b/nest/rt.h
@@ -0,0 +1,501 @@
+/*
+ *	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 */
+
+/*
+ *	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