2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Definitions for the Forwarding Information Base.
8 * Authors: A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
20 #include <linux/seq_file.h>
21 #include <linux/rcupdate.h>
22 #include <net/fib_notifier.h>
23 #include <net/fib_rules.h>
24 #include <net/inetpeer.h>
25 #include <linux/percpu.h>
26 #include <linux/notifier.h>
27 #include <linux/refcount.h>
41 struct in6_addr fc_gw6;
48 struct rtnexthop *fc_mp;
53 struct nl_info fc_nlinfo;
54 struct nlattr *fc_encap;
61 struct fib_nh_exception {
62 struct fib_nh_exception __rcu *fnhe_next;
68 unsigned long fnhe_expires;
69 struct rtable __rcu *fnhe_rth_input;
70 struct rtable __rcu *fnhe_rth_output;
71 unsigned long fnhe_stamp;
75 struct fnhe_hash_bucket {
76 struct fib_nh_exception __rcu *chain;
79 #define FNHE_HASH_SHIFT 11
80 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
81 #define FNHE_RECLAIM_DEPTH 5
83 struct fib_nh_common {
84 struct net_device *nhc_dev;
86 unsigned char nhc_scope;
89 unsigned char nhc_flags;
90 struct lwtunnel_state *nhc_lwtstate;
98 atomic_t nhc_upper_bound;
100 /* v4 specific, but allows fib6_nh with v4 routes */
101 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
102 struct rtable __rcu *nhc_rth_input;
103 struct fnhe_hash_bucket __rcu *nhc_exceptions;
107 struct fib_nh_common nh_common;
108 struct hlist_node nh_hash;
109 struct fib_info *nh_parent;
110 #ifdef CONFIG_IP_ROUTE_CLASSID
115 #define fib_nh_family nh_common.nhc_family
116 #define fib_nh_dev nh_common.nhc_dev
117 #define fib_nh_oif nh_common.nhc_oif
118 #define fib_nh_flags nh_common.nhc_flags
119 #define fib_nh_lws nh_common.nhc_lwtstate
120 #define fib_nh_scope nh_common.nhc_scope
121 #define fib_nh_gw_family nh_common.nhc_gw_family
122 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
123 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
124 #define fib_nh_weight nh_common.nhc_weight
125 #define fib_nh_upper_bound nh_common.nhc_upper_bound
129 * This structure contains data shared by many of routes.
133 struct hlist_node fib_hash;
134 struct hlist_node fib_lhash;
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]
155 struct fib_nh fib_nh[0];
156 #define fib_dev fib_nh[0].fib_nh_dev
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 static inline struct fib_nh_common *fib_info_nhc(struct fib_info *fi, int nhsel)
195 return &fi->fib_nh[nhsel].nh_common;
198 #ifdef CONFIG_IP_MULTIPLE_TABLES
199 #define FIB_TABLE_HASHSZ 256
201 #define FIB_TABLE_HASHSZ 2
204 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh,
205 unsigned char scope);
206 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
208 #define FIB_RES_NHC(res) ((res).nhc)
209 #define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
210 #define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
212 struct fib_entry_notifier_info {
213 struct fib_notifier_info info; /* must be first */
222 struct fib_nh_notifier_info {
223 struct fib_notifier_info info; /* must be first */
224 struct fib_nh *fib_nh;
227 int call_fib4_notifier(struct notifier_block *nb, struct net *net,
228 enum fib_event_type event_type,
229 struct fib_notifier_info *info);
230 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
231 struct fib_notifier_info *info);
233 int __net_init fib4_notifier_init(struct net *net);
234 void __net_exit fib4_notifier_exit(struct net *net);
236 void fib_info_notify_update(struct net *net, struct nl_info *info);
237 void fib_notify(struct net *net, struct notifier_block *nb);
240 struct hlist_node tb_hlist;
244 unsigned long *tb_data;
245 unsigned long __data[0];
248 struct fib_dump_filter {
250 /* filter_set is an optimization that an entry is set */
252 bool dump_all_families;
253 unsigned char protocol;
254 unsigned char rt_type;
256 struct net_device *dev;
259 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
260 struct fib_result *res, int fib_flags);
261 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
262 struct netlink_ext_ack *extack);
263 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
264 struct netlink_ext_ack *extack);
265 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
266 struct netlink_callback *cb, struct fib_dump_filter *filter);
267 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
268 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
269 void fib_table_flush_external(struct fib_table *table);
270 void fib_free_table(struct fib_table *tb);
272 #ifndef CONFIG_IP_MULTIPLE_TABLES
274 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
275 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
277 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
279 struct hlist_node *tb_hlist;
280 struct hlist_head *ptr;
282 ptr = id == RT_TABLE_LOCAL ?
283 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
284 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
286 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
288 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
291 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
293 return fib_get_table(net, id);
296 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
297 struct fib_result *res, unsigned int flags)
299 struct fib_table *tb;
300 int err = -ENETUNREACH;
304 tb = fib_get_table(net, RT_TABLE_MAIN);
306 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
316 static inline bool fib4_rule_default(const struct fib_rule *rule)
321 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
326 static inline unsigned int fib4_rules_seq_read(struct net *net)
331 static inline bool fib4_rules_early_flow_dissect(struct net *net,
334 struct flow_keys *flkeys)
338 #else /* CONFIG_IP_MULTIPLE_TABLES */
339 int __net_init fib4_rules_init(struct net *net);
340 void __net_exit fib4_rules_exit(struct net *net);
342 struct fib_table *fib_new_table(struct net *net, u32 id);
343 struct fib_table *fib_get_table(struct net *net, u32 id);
345 int __fib_lookup(struct net *net, struct flowi4 *flp,
346 struct fib_result *res, unsigned int flags);
348 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
349 struct fib_result *res, unsigned int flags)
351 struct fib_table *tb;
352 int err = -ENETUNREACH;
354 flags |= FIB_LOOKUP_NOREF;
355 if (net->ipv4.fib_has_custom_rules)
356 return __fib_lookup(net, flp, res, flags);
362 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
364 err = fib_table_lookup(tb, flp, res, flags);
369 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
371 err = fib_table_lookup(tb, flp, res, flags);
382 bool fib4_rule_default(const struct fib_rule *rule);
383 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
384 unsigned int fib4_rules_seq_read(struct net *net);
386 static inline bool fib4_rules_early_flow_dissect(struct net *net,
389 struct flow_keys *flkeys)
391 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
393 if (!net->ipv4.fib_rules_require_fldissect)
396 skb_flow_dissect_flow_keys(skb, flkeys, flag);
397 fl4->fl4_sport = flkeys->ports.src;
398 fl4->fl4_dport = flkeys->ports.dst;
399 fl4->flowi4_proto = flkeys->basic.ip_proto;
404 #endif /* CONFIG_IP_MULTIPLE_TABLES */
406 /* Exported by fib_frontend.c */
407 extern const struct nla_policy rtm_ipv4_policy[];
408 void ip_fib_init(void);
409 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
410 struct netlink_ext_ack *extack);
411 __be32 fib_compute_spec_dst(struct sk_buff *skb);
412 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
413 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
414 u8 tos, int oif, struct net_device *dev,
415 struct in_device *idev, u32 *itag);
416 #ifdef CONFIG_IP_ROUTE_CLASSID
417 static inline int fib_num_tclassid_users(struct net *net)
419 return net->ipv4.fib_num_tclassid_users;
422 static inline int fib_num_tclassid_users(struct net *net)
427 int fib_unmerge(struct net *net);
429 /* Exported by fib_semantics.c */
430 int ip_fib_check_default(__be32 gw, struct net_device *dev);
431 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
432 int fib_sync_down_addr(struct net_device *dev, __be32 local);
433 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
434 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
436 #ifdef CONFIG_IP_ROUTE_MULTIPATH
437 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
438 const struct sk_buff *skb, struct flow_keys *flkeys);
440 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
441 struct netlink_ext_ack *extack);
442 void fib_select_multipath(struct fib_result *res, int hash);
443 void fib_select_path(struct net *net, struct fib_result *res,
444 struct flowi4 *fl4, const struct sk_buff *skb);
446 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
447 struct fib_config *cfg, int nh_weight,
448 struct netlink_ext_ack *extack);
449 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
450 int fib_nh_common_init(struct fib_nh_common *nhc, struct nlattr *fc_encap,
451 u16 fc_encap_type, void *cfg, gfp_t gfp_flags,
452 struct netlink_ext_ack *extack);
453 void fib_nh_common_release(struct fib_nh_common *nhc);
455 /* Exported by fib_trie.c */
456 void fib_trie_init(void);
457 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
459 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
461 #ifdef CONFIG_IP_ROUTE_CLASSID
462 struct fib_nh_common *nhc = res->nhc;
463 struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
464 #ifdef CONFIG_IP_MULTIPLE_TABLES
467 *itag = nh->nh_tclassid << 16;
468 #ifdef CONFIG_IP_MULTIPLE_TABLES
469 rtag = res->tclassid;
477 void fib_flush(struct net *net);
478 void free_fib_info(struct fib_info *fi);
480 static inline void fib_info_hold(struct fib_info *fi)
482 refcount_inc(&fi->fib_clntref);
485 static inline void fib_info_put(struct fib_info *fi)
487 if (refcount_dec_and_test(&fi->fib_clntref))
491 #ifdef CONFIG_PROC_FS
492 int __net_init fib_proc_init(struct net *net);
493 void __net_exit fib_proc_exit(struct net *net);
495 static inline int fib_proc_init(struct net *net)
499 static inline void fib_proc_exit(struct net *net)
504 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
506 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
507 struct fib_dump_filter *filter,
508 struct netlink_callback *cb);
510 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
511 unsigned char *flags, bool skip_oif);
512 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
514 #endif /* _NET_FIB_H */