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_rules.h>
23 #include <net/inetpeer.h>
24 #include <linux/percpu.h>
25 #include <linux/notifier.h>
42 struct rtnexthop *fc_mp;
47 struct nl_info fc_nlinfo;
48 struct nlattr *fc_encap;
55 struct fib_nh_exception {
56 struct fib_nh_exception __rcu *fnhe_next;
61 unsigned long fnhe_expires;
62 struct rtable __rcu *fnhe_rth_input;
63 struct rtable __rcu *fnhe_rth_output;
64 unsigned long fnhe_stamp;
68 struct fnhe_hash_bucket {
69 struct fib_nh_exception __rcu *chain;
72 #define FNHE_HASH_SHIFT 11
73 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
74 #define FNHE_RECLAIM_DEPTH 5
77 struct net_device *nh_dev;
78 struct hlist_node nh_hash;
79 struct fib_info *nh_parent;
80 unsigned int nh_flags;
81 unsigned char nh_scope;
82 #ifdef CONFIG_IP_ROUTE_MULTIPATH
84 atomic_t nh_upper_bound;
86 #ifdef CONFIG_IP_ROUTE_CLASSID
93 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
94 struct rtable __rcu *nh_rth_input;
95 struct fnhe_hash_bucket __rcu *nh_exceptions;
96 struct lwtunnel_state *nh_lwtstate;
100 * This structure contains data shared by many of routes.
104 struct hlist_node fib_hash;
105 struct hlist_node fib_lhash;
108 atomic_t fib_clntref;
109 unsigned int fib_flags;
110 unsigned char fib_dead;
111 unsigned char fib_protocol;
112 unsigned char fib_scope;
113 unsigned char fib_type;
118 #define fib_mtu fib_metrics[RTAX_MTU-1]
119 #define fib_window fib_metrics[RTAX_WINDOW-1]
120 #define fib_rtt fib_metrics[RTAX_RTT-1]
121 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
123 #ifdef CONFIG_IP_ROUTE_MULTIPATH
126 unsigned int fib_offload_cnt;
128 struct fib_nh fib_nh[0];
129 #define fib_dev fib_nh[0].nh_dev
133 #ifdef CONFIG_IP_MULTIPLE_TABLES
139 unsigned char prefixlen;
140 unsigned char nh_sel;
145 struct fib_table *table;
146 struct hlist_head *fa_head;
149 struct fib_result_nl {
150 __be32 fl_addr; /* To be looked up*/
152 unsigned char fl_tos;
153 unsigned char fl_scope;
154 unsigned char tb_id_in;
156 unsigned char tb_id; /* Results */
157 unsigned char prefixlen;
158 unsigned char nh_sel;
164 #ifdef CONFIG_IP_ROUTE_MULTIPATH
165 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
166 #else /* CONFIG_IP_ROUTE_MULTIPATH */
167 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
168 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
170 #ifdef CONFIG_IP_MULTIPLE_TABLES
171 #define FIB_TABLE_HASHSZ 256
173 #define FIB_TABLE_HASHSZ 2
176 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
178 static inline void fib_info_offload_inc(struct fib_info *fi)
180 fi->fib_offload_cnt++;
181 fi->fib_flags |= RTNH_F_OFFLOAD;
184 static inline void fib_info_offload_dec(struct fib_info *fi)
186 if (--fi->fib_offload_cnt == 0)
187 fi->fib_flags &= ~RTNH_F_OFFLOAD;
190 #define FIB_RES_SADDR(net, res) \
191 ((FIB_RES_NH(res).nh_saddr_genid == \
192 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
193 FIB_RES_NH(res).nh_saddr : \
194 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
195 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
196 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
197 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
199 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
200 FIB_RES_SADDR(net, res))
202 struct fib_notifier_info {
206 struct fib_entry_notifier_info {
207 struct fib_notifier_info info; /* must be first */
216 struct fib_rule_notifier_info {
217 struct fib_notifier_info info; /* must be first */
218 struct fib_rule *rule;
221 struct fib_nh_notifier_info {
222 struct fib_notifier_info info; /* must be first */
223 struct fib_nh *fib_nh;
226 enum fib_event_type {
227 FIB_EVENT_ENTRY_REPLACE,
228 FIB_EVENT_ENTRY_APPEND,
237 int register_fib_notifier(struct notifier_block *nb,
238 void (*cb)(struct notifier_block *nb));
239 int unregister_fib_notifier(struct notifier_block *nb);
240 int call_fib_notifier(struct notifier_block *nb, struct net *net,
241 enum fib_event_type event_type,
242 struct fib_notifier_info *info);
243 int call_fib_notifiers(struct net *net, enum fib_event_type event_type,
244 struct fib_notifier_info *info);
246 void fib_notify(struct net *net, struct notifier_block *nb);
247 #ifdef CONFIG_IP_MULTIPLE_TABLES
248 void fib_rules_notify(struct net *net, struct notifier_block *nb);
250 static inline void fib_rules_notify(struct net *net, struct notifier_block *nb)
256 struct hlist_node tb_hlist;
260 unsigned long *tb_data;
261 unsigned long __data[0];
264 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
265 struct fib_result *res, int fib_flags);
266 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *);
267 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *);
268 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
269 struct netlink_callback *cb);
270 int fib_table_flush(struct net *net, struct fib_table *table);
271 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
272 void fib_table_flush_external(struct fib_table *table);
273 void fib_free_table(struct fib_table *tb);
275 #ifndef CONFIG_IP_MULTIPLE_TABLES
277 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
278 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
280 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
282 struct hlist_node *tb_hlist;
283 struct hlist_head *ptr;
285 ptr = id == RT_TABLE_LOCAL ?
286 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
287 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
289 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
291 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
294 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
296 return fib_get_table(net, id);
299 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
300 struct fib_result *res, unsigned int flags)
302 struct fib_table *tb;
303 int err = -ENETUNREACH;
307 tb = fib_get_table(net, RT_TABLE_MAIN);
309 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
319 static inline bool fib4_rule_default(const struct fib_rule *rule)
324 #else /* CONFIG_IP_MULTIPLE_TABLES */
325 int __net_init fib4_rules_init(struct net *net);
326 void __net_exit fib4_rules_exit(struct net *net);
328 struct fib_table *fib_new_table(struct net *net, u32 id);
329 struct fib_table *fib_get_table(struct net *net, u32 id);
331 int __fib_lookup(struct net *net, struct flowi4 *flp,
332 struct fib_result *res, unsigned int flags);
334 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
335 struct fib_result *res, unsigned int flags)
337 struct fib_table *tb;
338 int err = -ENETUNREACH;
340 flags |= FIB_LOOKUP_NOREF;
341 if (net->ipv4.fib_has_custom_rules)
342 return __fib_lookup(net, flp, res, flags);
348 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
350 err = fib_table_lookup(tb, flp, res, flags);
355 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
357 err = fib_table_lookup(tb, flp, res, flags);
368 bool fib4_rule_default(const struct fib_rule *rule);
370 #endif /* CONFIG_IP_MULTIPLE_TABLES */
372 /* Exported by fib_frontend.c */
373 extern const struct nla_policy rtm_ipv4_policy[];
374 void ip_fib_init(void);
375 __be32 fib_compute_spec_dst(struct sk_buff *skb);
376 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
377 u8 tos, int oif, struct net_device *dev,
378 struct in_device *idev, u32 *itag);
379 #ifdef CONFIG_IP_ROUTE_CLASSID
380 static inline int fib_num_tclassid_users(struct net *net)
382 return net->ipv4.fib_num_tclassid_users;
385 static inline int fib_num_tclassid_users(struct net *net)
390 int fib_unmerge(struct net *net);
392 /* Exported by fib_semantics.c */
393 int ip_fib_check_default(__be32 gw, struct net_device *dev);
394 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
395 int fib_sync_down_addr(struct net_device *dev, __be32 local);
396 int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
398 #ifdef CONFIG_IP_ROUTE_MULTIPATH
399 int fib_multipath_hash(const struct fib_info *fi, const struct flowi4 *fl4,
400 const struct sk_buff *skb);
402 void fib_select_multipath(struct fib_result *res, int hash);
403 void fib_select_path(struct net *net, struct fib_result *res,
404 struct flowi4 *fl4, const struct sk_buff *skb);
406 /* Exported by fib_trie.c */
407 void fib_trie_init(void);
408 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
410 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
412 #ifdef CONFIG_IP_ROUTE_CLASSID
413 #ifdef CONFIG_IP_MULTIPLE_TABLES
416 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
417 #ifdef CONFIG_IP_MULTIPLE_TABLES
418 rtag = res->tclassid;
426 void free_fib_info(struct fib_info *fi);
428 static inline void fib_info_hold(struct fib_info *fi)
430 atomic_inc(&fi->fib_clntref);
433 static inline void fib_info_put(struct fib_info *fi)
435 if (atomic_dec_and_test(&fi->fib_clntref))
439 #ifdef CONFIG_PROC_FS
440 int __net_init fib_proc_init(struct net *net);
441 void __net_exit fib_proc_exit(struct net *net);
443 static inline int fib_proc_init(struct net *net)
447 static inline void fib_proc_exit(struct net *net)
452 #endif /* _NET_FIB_H */