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>
44 struct rtnexthop *fc_mp;
49 struct nl_info fc_nlinfo;
50 struct nlattr *fc_encap;
57 struct fib_nh_exception {
58 struct fib_nh_exception __rcu *fnhe_next;
63 unsigned long fnhe_expires;
64 struct rtable __rcu *fnhe_rth_input;
65 struct rtable __rcu *fnhe_rth_output;
66 unsigned long fnhe_stamp;
70 struct fnhe_hash_bucket {
71 struct fib_nh_exception __rcu *chain;
74 #define FNHE_HASH_SHIFT 11
75 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
76 #define FNHE_RECLAIM_DEPTH 5
79 struct net_device *nh_dev;
80 struct hlist_node nh_hash;
81 struct fib_info *nh_parent;
82 unsigned int nh_flags;
83 unsigned char nh_scope;
84 #ifdef CONFIG_IP_ROUTE_MULTIPATH
86 atomic_t nh_upper_bound;
88 #ifdef CONFIG_IP_ROUTE_CLASSID
95 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
96 struct rtable __rcu *nh_rth_input;
97 struct fnhe_hash_bucket __rcu *nh_exceptions;
98 struct lwtunnel_state *nh_lwtstate;
102 * This structure contains data shared by many of routes.
106 struct hlist_node fib_hash;
107 struct hlist_node fib_lhash;
110 refcount_t fib_clntref;
111 unsigned int fib_flags;
112 unsigned char fib_dead;
113 unsigned char fib_protocol;
114 unsigned char fib_scope;
115 unsigned char fib_type;
119 struct dst_metrics *fib_metrics;
120 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
121 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
122 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
123 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
125 #ifdef CONFIG_IP_ROUTE_MULTIPATH
129 struct fib_nh fib_nh[0];
130 #define fib_dev fib_nh[0].nh_dev
134 #ifdef CONFIG_IP_MULTIPLE_TABLES
141 unsigned char prefixlen;
142 unsigned char nh_sel;
147 struct fib_table *table;
148 struct hlist_head *fa_head;
151 struct fib_result_nl {
152 __be32 fl_addr; /* To be looked up*/
154 unsigned char fl_tos;
155 unsigned char fl_scope;
156 unsigned char tb_id_in;
158 unsigned char tb_id; /* Results */
159 unsigned char prefixlen;
160 unsigned char nh_sel;
166 #ifdef CONFIG_IP_ROUTE_MULTIPATH
167 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
168 #else /* CONFIG_IP_ROUTE_MULTIPATH */
169 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
170 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
172 #ifdef CONFIG_IP_MULTIPLE_TABLES
173 #define FIB_TABLE_HASHSZ 256
175 #define FIB_TABLE_HASHSZ 2
178 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
180 #define FIB_RES_SADDR(net, res) \
181 ((FIB_RES_NH(res).nh_saddr_genid == \
182 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
183 FIB_RES_NH(res).nh_saddr : \
184 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
185 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
186 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
187 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
189 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
190 FIB_RES_SADDR(net, res))
192 struct fib_entry_notifier_info {
193 struct fib_notifier_info info; /* must be first */
202 struct fib_nh_notifier_info {
203 struct fib_notifier_info info; /* must be first */
204 struct fib_nh *fib_nh;
207 int call_fib4_notifier(struct notifier_block *nb, struct net *net,
208 enum fib_event_type event_type,
209 struct fib_notifier_info *info);
210 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
211 struct fib_notifier_info *info);
213 int __net_init fib4_notifier_init(struct net *net);
214 void __net_exit fib4_notifier_exit(struct net *net);
216 void fib_notify(struct net *net, struct notifier_block *nb);
219 struct hlist_node tb_hlist;
223 unsigned long *tb_data;
224 unsigned long __data[0];
227 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
228 struct fib_result *res, int fib_flags);
229 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
230 struct netlink_ext_ack *extack);
231 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
232 struct netlink_ext_ack *extack);
233 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
234 struct netlink_callback *cb);
235 int fib_table_flush(struct net *net, struct fib_table *table);
236 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
237 void fib_table_flush_external(struct fib_table *table);
238 void fib_free_table(struct fib_table *tb);
240 #ifndef CONFIG_IP_MULTIPLE_TABLES
242 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
243 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
245 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
247 struct hlist_node *tb_hlist;
248 struct hlist_head *ptr;
250 ptr = id == RT_TABLE_LOCAL ?
251 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
252 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
254 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
256 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
259 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
261 return fib_get_table(net, id);
264 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
265 struct fib_result *res, unsigned int flags)
267 struct fib_table *tb;
268 int err = -ENETUNREACH;
272 tb = fib_get_table(net, RT_TABLE_MAIN);
274 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
284 static inline bool fib4_rule_default(const struct fib_rule *rule)
289 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
294 static inline unsigned int fib4_rules_seq_read(struct net *net)
299 #else /* CONFIG_IP_MULTIPLE_TABLES */
300 int __net_init fib4_rules_init(struct net *net);
301 void __net_exit fib4_rules_exit(struct net *net);
303 struct fib_table *fib_new_table(struct net *net, u32 id);
304 struct fib_table *fib_get_table(struct net *net, u32 id);
306 int __fib_lookup(struct net *net, struct flowi4 *flp,
307 struct fib_result *res, unsigned int flags);
309 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
310 struct fib_result *res, unsigned int flags)
312 struct fib_table *tb;
313 int err = -ENETUNREACH;
315 flags |= FIB_LOOKUP_NOREF;
316 if (net->ipv4.fib_has_custom_rules)
317 return __fib_lookup(net, flp, res, flags);
323 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
325 err = fib_table_lookup(tb, flp, res, flags);
330 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
332 err = fib_table_lookup(tb, flp, res, flags);
343 bool fib4_rule_default(const struct fib_rule *rule);
344 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
345 unsigned int fib4_rules_seq_read(struct net *net);
347 #endif /* CONFIG_IP_MULTIPLE_TABLES */
349 /* Exported by fib_frontend.c */
350 extern const struct nla_policy rtm_ipv4_policy[];
351 void ip_fib_init(void);
352 __be32 fib_compute_spec_dst(struct sk_buff *skb);
353 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
354 u8 tos, int oif, struct net_device *dev,
355 struct in_device *idev, u32 *itag);
356 #ifdef CONFIG_IP_ROUTE_CLASSID
357 static inline int fib_num_tclassid_users(struct net *net)
359 return net->ipv4.fib_num_tclassid_users;
362 static inline int fib_num_tclassid_users(struct net *net)
367 int fib_unmerge(struct net *net);
369 /* Exported by fib_semantics.c */
370 int ip_fib_check_default(__be32 gw, struct net_device *dev);
371 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
372 int fib_sync_down_addr(struct net_device *dev, __be32 local);
373 int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
375 #ifdef CONFIG_IP_ROUTE_MULTIPATH
376 int fib_multipath_hash(const struct fib_info *fi, const struct flowi4 *fl4,
377 const struct sk_buff *skb);
379 void fib_select_multipath(struct fib_result *res, int hash);
380 void fib_select_path(struct net *net, struct fib_result *res,
381 struct flowi4 *fl4, const struct sk_buff *skb);
383 /* Exported by fib_trie.c */
384 void fib_trie_init(void);
385 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
387 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
389 #ifdef CONFIG_IP_ROUTE_CLASSID
390 #ifdef CONFIG_IP_MULTIPLE_TABLES
393 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
394 #ifdef CONFIG_IP_MULTIPLE_TABLES
395 rtag = res->tclassid;
403 void free_fib_info(struct fib_info *fi);
405 static inline void fib_info_hold(struct fib_info *fi)
407 refcount_inc(&fi->fib_clntref);
410 static inline void fib_info_put(struct fib_info *fi)
412 if (refcount_dec_and_test(&fi->fib_clntref))
416 #ifdef CONFIG_PROC_FS
417 int __net_init fib_proc_init(struct net *net);
418 void __net_exit fib_proc_exit(struct net *net);
420 static inline int fib_proc_init(struct net *net)
424 static inline void fib_proc_exit(struct net *net)
429 #endif /* _NET_FIB_H */