1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Definitions for the Forwarding Information Base.
9 * Authors: A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
16 #include <linux/seq_file.h>
17 #include <linux/rcupdate.h>
18 #include <net/fib_notifier.h>
19 #include <net/fib_rules.h>
20 #include <net/inetpeer.h>
21 #include <linux/percpu.h>
22 #include <linux/notifier.h>
23 #include <linux/refcount.h>
37 struct in6_addr fc_gw6;
45 struct rtnexthop *fc_mp;
50 struct nl_info fc_nlinfo;
51 struct nlattr *fc_encap;
58 struct fib_nh_exception {
59 struct fib_nh_exception __rcu *fnhe_next;
65 unsigned long fnhe_expires;
66 struct rtable __rcu *fnhe_rth_input;
67 struct rtable __rcu *fnhe_rth_output;
68 unsigned long fnhe_stamp;
72 struct fnhe_hash_bucket {
73 struct fib_nh_exception __rcu *chain;
76 #define FNHE_HASH_SHIFT 11
77 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
78 #define FNHE_RECLAIM_DEPTH 5
80 struct fib_nh_common {
81 struct net_device *nhc_dev;
83 unsigned char nhc_scope;
86 unsigned char nhc_flags;
87 struct lwtunnel_state *nhc_lwtstate;
95 atomic_t nhc_upper_bound;
97 /* v4 specific, but allows fib6_nh with v4 routes */
98 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
99 struct rtable __rcu *nhc_rth_input;
100 struct fnhe_hash_bucket __rcu *nhc_exceptions;
104 struct fib_nh_common nh_common;
105 struct hlist_node nh_hash;
106 struct fib_info *nh_parent;
107 #ifdef CONFIG_IP_ROUTE_CLASSID
112 #define fib_nh_family nh_common.nhc_family
113 #define fib_nh_dev nh_common.nhc_dev
114 #define fib_nh_oif nh_common.nhc_oif
115 #define fib_nh_flags nh_common.nhc_flags
116 #define fib_nh_lws nh_common.nhc_lwtstate
117 #define fib_nh_scope nh_common.nhc_scope
118 #define fib_nh_gw_family nh_common.nhc_gw_family
119 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
120 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
121 #define fib_nh_weight nh_common.nhc_weight
122 #define fib_nh_upper_bound nh_common.nhc_upper_bound
126 * This structure contains data shared by many of routes.
132 struct hlist_node fib_hash;
133 struct hlist_node fib_lhash;
134 struct list_head nh_list;
137 refcount_t fib_clntref;
138 unsigned int fib_flags;
139 unsigned char fib_dead;
140 unsigned char fib_protocol;
141 unsigned char fib_scope;
142 unsigned char fib_type;
146 struct dst_metrics *fib_metrics;
147 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
148 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
149 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
150 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
156 struct fib_nh fib_nh[0];
160 #ifdef CONFIG_IP_MULTIPLE_TABLES
167 unsigned char prefixlen;
168 unsigned char nh_sel;
172 struct fib_nh_common *nhc;
174 struct fib_table *table;
175 struct hlist_head *fa_head;
178 struct fib_result_nl {
179 __be32 fl_addr; /* To be looked up*/
181 unsigned char fl_tos;
182 unsigned char fl_scope;
183 unsigned char tb_id_in;
185 unsigned char tb_id; /* Results */
186 unsigned char prefixlen;
187 unsigned char nh_sel;
193 #ifdef CONFIG_IP_MULTIPLE_TABLES
194 #define FIB_TABLE_HASHSZ 256
196 #define FIB_TABLE_HASHSZ 2
199 __be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
200 unsigned char scope);
201 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
203 #define FIB_RES_NHC(res) ((res).nhc)
204 #define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
205 #define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
207 struct fib_entry_notifier_info {
208 struct fib_notifier_info info; /* must be first */
217 struct fib_nh_notifier_info {
218 struct fib_notifier_info info; /* must be first */
219 struct fib_nh *fib_nh;
222 int call_fib4_notifier(struct notifier_block *nb, struct net *net,
223 enum fib_event_type event_type,
224 struct fib_notifier_info *info);
225 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
226 struct fib_notifier_info *info);
228 int __net_init fib4_notifier_init(struct net *net);
229 void __net_exit fib4_notifier_exit(struct net *net);
231 void fib_info_notify_update(struct net *net, struct nl_info *info);
232 void fib_notify(struct net *net, struct notifier_block *nb);
235 struct hlist_node tb_hlist;
239 unsigned long *tb_data;
240 unsigned long __data[0];
243 struct fib_dump_filter {
245 /* filter_set is an optimization that an entry is set */
247 bool dump_all_families;
248 unsigned char protocol;
249 unsigned char rt_type;
251 struct net_device *dev;
254 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
255 struct fib_result *res, int fib_flags);
256 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
257 struct netlink_ext_ack *extack);
258 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
259 struct netlink_ext_ack *extack);
260 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
261 struct netlink_callback *cb, struct fib_dump_filter *filter);
262 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
263 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
264 void fib_table_flush_external(struct fib_table *table);
265 void fib_free_table(struct fib_table *tb);
267 #ifndef CONFIG_IP_MULTIPLE_TABLES
269 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
270 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
272 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
274 struct hlist_node *tb_hlist;
275 struct hlist_head *ptr;
277 ptr = id == RT_TABLE_LOCAL ?
278 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
279 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
281 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
283 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
286 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
288 return fib_get_table(net, id);
291 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
292 struct fib_result *res, unsigned int flags)
294 struct fib_table *tb;
295 int err = -ENETUNREACH;
299 tb = fib_get_table(net, RT_TABLE_MAIN);
301 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
311 static inline bool fib4_rule_default(const struct fib_rule *rule)
316 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
321 static inline unsigned int fib4_rules_seq_read(struct net *net)
326 static inline bool fib4_rules_early_flow_dissect(struct net *net,
329 struct flow_keys *flkeys)
333 #else /* CONFIG_IP_MULTIPLE_TABLES */
334 int __net_init fib4_rules_init(struct net *net);
335 void __net_exit fib4_rules_exit(struct net *net);
337 struct fib_table *fib_new_table(struct net *net, u32 id);
338 struct fib_table *fib_get_table(struct net *net, u32 id);
340 int __fib_lookup(struct net *net, struct flowi4 *flp,
341 struct fib_result *res, unsigned int flags);
343 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
344 struct fib_result *res, unsigned int flags)
346 struct fib_table *tb;
347 int err = -ENETUNREACH;
349 flags |= FIB_LOOKUP_NOREF;
350 if (net->ipv4.fib_has_custom_rules)
351 return __fib_lookup(net, flp, res, flags);
357 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
359 err = fib_table_lookup(tb, flp, res, flags);
364 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
366 err = fib_table_lookup(tb, flp, res, flags);
377 bool fib4_rule_default(const struct fib_rule *rule);
378 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
379 unsigned int fib4_rules_seq_read(struct net *net);
381 static inline bool fib4_rules_early_flow_dissect(struct net *net,
384 struct flow_keys *flkeys)
386 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
388 if (!net->ipv4.fib_rules_require_fldissect)
391 skb_flow_dissect_flow_keys(skb, flkeys, flag);
392 fl4->fl4_sport = flkeys->ports.src;
393 fl4->fl4_dport = flkeys->ports.dst;
394 fl4->flowi4_proto = flkeys->basic.ip_proto;
399 #endif /* CONFIG_IP_MULTIPLE_TABLES */
401 /* Exported by fib_frontend.c */
402 extern const struct nla_policy rtm_ipv4_policy[];
403 void ip_fib_init(void);
404 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
405 struct netlink_ext_ack *extack);
406 __be32 fib_compute_spec_dst(struct sk_buff *skb);
407 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
408 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
409 u8 tos, int oif, struct net_device *dev,
410 struct in_device *idev, u32 *itag);
411 #ifdef CONFIG_IP_ROUTE_CLASSID
412 static inline int fib_num_tclassid_users(struct net *net)
414 return net->ipv4.fib_num_tclassid_users;
417 static inline int fib_num_tclassid_users(struct net *net)
422 int fib_unmerge(struct net *net);
424 /* Exported by fib_semantics.c */
425 int ip_fib_check_default(__be32 gw, struct net_device *dev);
426 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
427 int fib_sync_down_addr(struct net_device *dev, __be32 local);
428 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
429 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
430 void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
432 #ifdef CONFIG_IP_ROUTE_MULTIPATH
433 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
434 const struct sk_buff *skb, struct flow_keys *flkeys);
436 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
437 struct netlink_ext_ack *extack);
438 void fib_select_multipath(struct fib_result *res, int hash);
439 void fib_select_path(struct net *net, struct fib_result *res,
440 struct flowi4 *fl4, const struct sk_buff *skb);
442 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
443 struct fib_config *cfg, int nh_weight,
444 struct netlink_ext_ack *extack);
445 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
446 int fib_nh_common_init(struct fib_nh_common *nhc, struct nlattr *fc_encap,
447 u16 fc_encap_type, void *cfg, gfp_t gfp_flags,
448 struct netlink_ext_ack *extack);
449 void fib_nh_common_release(struct fib_nh_common *nhc);
451 /* Exported by fib_trie.c */
452 void fib_trie_init(void);
453 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
455 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
457 #ifdef CONFIG_IP_ROUTE_CLASSID
458 struct fib_nh_common *nhc = res->nhc;
459 #ifdef CONFIG_IP_MULTIPLE_TABLES
462 if (nhc->nhc_family == AF_INET) {
465 nh = container_of(nhc, struct fib_nh, nh_common);
466 *itag = nh->nh_tclassid << 16;
471 #ifdef CONFIG_IP_MULTIPLE_TABLES
472 rtag = res->tclassid;
480 void fib_flush(struct net *net);
481 void free_fib_info(struct fib_info *fi);
483 static inline void fib_info_hold(struct fib_info *fi)
485 refcount_inc(&fi->fib_clntref);
488 static inline void fib_info_put(struct fib_info *fi)
490 if (refcount_dec_and_test(&fi->fib_clntref))
494 #ifdef CONFIG_PROC_FS
495 int __net_init fib_proc_init(struct net *net);
496 void __net_exit fib_proc_exit(struct net *net);
498 static inline int fib_proc_init(struct net *net)
502 static inline void fib_proc_exit(struct net *net)
507 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
509 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
510 struct fib_dump_filter *filter,
511 struct netlink_callback *cb);
513 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
514 unsigned char *flags, bool skip_oif);
515 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
517 #endif /* _NET_FIB_H */