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>
41 struct rtnexthop *fc_mp;
46 struct nl_info fc_nlinfo;
47 struct nlattr *fc_encap;
54 struct fib_nh_exception {
55 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;
117 struct dst_metrics *fib_metrics;
118 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
119 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
120 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
121 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
123 #ifdef CONFIG_IP_ROUTE_MULTIPATH
127 struct fib_nh fib_nh[0];
128 #define fib_dev fib_nh[0].nh_dev
132 #ifdef CONFIG_IP_MULTIPLE_TABLES
138 unsigned char prefixlen;
139 unsigned char nh_sel;
144 struct fib_table *table;
145 struct hlist_head *fa_head;
148 struct fib_result_nl {
149 __be32 fl_addr; /* To be looked up*/
151 unsigned char fl_tos;
152 unsigned char fl_scope;
153 unsigned char tb_id_in;
155 unsigned char tb_id; /* Results */
156 unsigned char prefixlen;
157 unsigned char nh_sel;
163 #ifdef CONFIG_IP_ROUTE_MULTIPATH
164 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
165 #else /* CONFIG_IP_ROUTE_MULTIPATH */
166 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
167 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
169 #ifdef CONFIG_IP_MULTIPLE_TABLES
170 #define FIB_TABLE_HASHSZ 256
172 #define FIB_TABLE_HASHSZ 2
175 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
177 #define FIB_RES_SADDR(net, res) \
178 ((FIB_RES_NH(res).nh_saddr_genid == \
179 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
180 FIB_RES_NH(res).nh_saddr : \
181 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
182 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
183 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
184 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
186 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
187 FIB_RES_SADDR(net, res))
190 struct hlist_node tb_hlist;
194 unsigned long *tb_data;
195 unsigned long __data[0];
198 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
199 struct fib_result *res, int fib_flags);
200 int fib_table_insert(struct fib_table *, struct fib_config *);
201 int fib_table_delete(struct fib_table *, struct fib_config *);
202 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
203 struct netlink_callback *cb);
204 int fib_table_flush(struct fib_table *table, bool flush_all);
205 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
206 void fib_table_flush_external(struct fib_table *table);
207 void fib_free_table(struct fib_table *tb);
209 #ifndef CONFIG_IP_MULTIPLE_TABLES
211 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
212 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
214 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
216 struct hlist_node *tb_hlist;
217 struct hlist_head *ptr;
219 ptr = id == RT_TABLE_LOCAL ?
220 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
221 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
223 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
225 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
228 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
230 return fib_get_table(net, id);
233 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
234 struct fib_result *res, unsigned int flags)
236 struct fib_table *tb;
237 int err = -ENETUNREACH;
241 tb = fib_get_table(net, RT_TABLE_MAIN);
243 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
253 #else /* CONFIG_IP_MULTIPLE_TABLES */
254 int __net_init fib4_rules_init(struct net *net);
255 void __net_exit fib4_rules_exit(struct net *net);
257 struct fib_table *fib_new_table(struct net *net, u32 id);
258 struct fib_table *fib_get_table(struct net *net, u32 id);
260 int __fib_lookup(struct net *net, struct flowi4 *flp,
261 struct fib_result *res, unsigned int flags);
263 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
264 struct fib_result *res, unsigned int flags)
266 struct fib_table *tb;
267 int err = -ENETUNREACH;
269 flags |= FIB_LOOKUP_NOREF;
270 if (net->ipv4.fib_has_custom_rules)
271 return __fib_lookup(net, flp, res, flags);
277 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
279 err = fib_table_lookup(tb, flp, res, flags);
284 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
286 err = fib_table_lookup(tb, flp, res, flags);
297 #endif /* CONFIG_IP_MULTIPLE_TABLES */
299 /* Exported by fib_frontend.c */
300 extern const struct nla_policy rtm_ipv4_policy[];
301 void ip_fib_init(void);
302 __be32 fib_compute_spec_dst(struct sk_buff *skb);
303 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
304 u8 tos, int oif, struct net_device *dev,
305 struct in_device *idev, u32 *itag);
306 void fib_select_default(const struct flowi4 *flp, struct fib_result *res);
307 #ifdef CONFIG_IP_ROUTE_CLASSID
308 static inline int fib_num_tclassid_users(struct net *net)
310 return net->ipv4.fib_num_tclassid_users;
313 static inline int fib_num_tclassid_users(struct net *net)
318 int fib_unmerge(struct net *net);
319 void fib_flush_external(struct net *net);
321 /* Exported by fib_semantics.c */
322 int ip_fib_check_default(__be32 gw, struct net_device *dev);
323 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
324 int fib_sync_down_addr(struct net_device *dev, __be32 local);
325 int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
326 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
328 extern u32 fib_multipath_secret __read_mostly;
330 static inline int fib_multipath_hash(__be32 saddr, __be32 daddr)
332 return jhash_2words(saddr, daddr, fib_multipath_secret) >> 1;
335 void fib_select_multipath(struct fib_result *res, int hash);
336 void fib_select_path(struct net *net, struct fib_result *res,
337 struct flowi4 *fl4, int mp_hash);
339 /* Exported by fib_trie.c */
340 void fib_trie_init(void);
341 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
343 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
345 #ifdef CONFIG_IP_ROUTE_CLASSID
346 #ifdef CONFIG_IP_MULTIPLE_TABLES
349 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
350 #ifdef CONFIG_IP_MULTIPLE_TABLES
351 rtag = res->tclassid;
359 void free_fib_info(struct fib_info *fi);
361 static inline void fib_info_put(struct fib_info *fi)
363 if (atomic_dec_and_test(&fi->fib_clntref))
367 #ifdef CONFIG_PROC_FS
368 int __net_init fib_proc_init(struct net *net);
369 void __net_exit fib_proc_exit(struct net *net);
371 static inline int fib_proc_init(struct net *net)
375 static inline void fib_proc_exit(struct net *net)
380 #endif /* _NET_FIB_H */