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;
60 unsigned long fnhe_expires;
61 struct rtable __rcu *fnhe_rth_input;
62 struct rtable __rcu *fnhe_rth_output;
63 unsigned long fnhe_stamp;
67 struct fnhe_hash_bucket {
68 struct fib_nh_exception __rcu *chain;
71 #define FNHE_HASH_SHIFT 11
72 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
73 #define FNHE_RECLAIM_DEPTH 5
76 struct net_device *nh_dev;
77 struct hlist_node nh_hash;
78 struct fib_info *nh_parent;
79 unsigned int nh_flags;
80 unsigned char nh_scope;
81 #ifdef CONFIG_IP_ROUTE_MULTIPATH
83 atomic_t nh_upper_bound;
85 #ifdef CONFIG_IP_ROUTE_CLASSID
92 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
93 struct rtable __rcu *nh_rth_input;
94 struct fnhe_hash_bucket __rcu *nh_exceptions;
95 struct lwtunnel_state *nh_lwtstate;
99 * This structure contains data shared by many of routes.
103 struct hlist_node fib_hash;
104 struct hlist_node fib_lhash;
107 atomic_t fib_clntref;
108 unsigned int fib_flags;
109 unsigned char fib_dead;
110 unsigned char fib_protocol;
111 unsigned char fib_scope;
112 unsigned char fib_type;
117 #define fib_mtu fib_metrics[RTAX_MTU-1]
118 #define fib_window fib_metrics[RTAX_WINDOW-1]
119 #define fib_rtt fib_metrics[RTAX_RTT-1]
120 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
122 #ifdef CONFIG_IP_ROUTE_MULTIPATH
126 struct fib_nh fib_nh[0];
127 #define fib_dev fib_nh[0].nh_dev
131 #ifdef CONFIG_IP_MULTIPLE_TABLES
137 unsigned char prefixlen;
138 unsigned char nh_sel;
143 struct fib_table *table;
144 struct hlist_head *fa_head;
147 struct fib_result_nl {
148 __be32 fl_addr; /* To be looked up*/
150 unsigned char fl_tos;
151 unsigned char fl_scope;
152 unsigned char tb_id_in;
154 unsigned char tb_id; /* Results */
155 unsigned char prefixlen;
156 unsigned char nh_sel;
162 #ifdef CONFIG_IP_ROUTE_MULTIPATH
163 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
164 #else /* CONFIG_IP_ROUTE_MULTIPATH */
165 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
166 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
168 #ifdef CONFIG_IP_MULTIPLE_TABLES
169 #define FIB_TABLE_HASHSZ 256
171 #define FIB_TABLE_HASHSZ 2
174 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
176 #define FIB_RES_SADDR(net, res) \
177 ((FIB_RES_NH(res).nh_saddr_genid == \
178 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
179 FIB_RES_NH(res).nh_saddr : \
180 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
181 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
182 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
183 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
185 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
186 FIB_RES_SADDR(net, res))
189 struct hlist_node tb_hlist;
193 unsigned long *tb_data;
194 unsigned long __data[0];
197 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
198 struct fib_result *res, int fib_flags);
199 int fib_table_insert(struct fib_table *, struct fib_config *);
200 int fib_table_delete(struct fib_table *, struct fib_config *);
201 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
202 struct netlink_callback *cb);
203 int fib_table_flush(struct fib_table *table);
204 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
205 void fib_table_flush_external(struct fib_table *table);
206 void fib_free_table(struct fib_table *tb);
208 #ifndef CONFIG_IP_MULTIPLE_TABLES
210 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
211 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
213 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
215 struct hlist_node *tb_hlist;
216 struct hlist_head *ptr;
218 ptr = id == RT_TABLE_LOCAL ?
219 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
220 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
222 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
224 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
227 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
229 return fib_get_table(net, id);
232 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
233 struct fib_result *res, unsigned int flags)
235 struct fib_table *tb;
236 int err = -ENETUNREACH;
240 tb = fib_get_table(net, RT_TABLE_MAIN);
242 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
252 #else /* CONFIG_IP_MULTIPLE_TABLES */
253 int __net_init fib4_rules_init(struct net *net);
254 void __net_exit fib4_rules_exit(struct net *net);
256 struct fib_table *fib_new_table(struct net *net, u32 id);
257 struct fib_table *fib_get_table(struct net *net, u32 id);
259 int __fib_lookup(struct net *net, struct flowi4 *flp,
260 struct fib_result *res, unsigned int flags);
262 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
263 struct fib_result *res, unsigned int flags)
265 struct fib_table *tb;
266 int err = -ENETUNREACH;
268 flags |= FIB_LOOKUP_NOREF;
269 if (net->ipv4.fib_has_custom_rules)
270 return __fib_lookup(net, flp, res, flags);
276 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
278 err = fib_table_lookup(tb, flp, res, flags);
283 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
285 err = fib_table_lookup(tb, flp, res, flags);
296 #endif /* CONFIG_IP_MULTIPLE_TABLES */
298 /* Exported by fib_frontend.c */
299 extern const struct nla_policy rtm_ipv4_policy[];
300 void ip_fib_init(void);
301 __be32 fib_compute_spec_dst(struct sk_buff *skb);
302 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
303 u8 tos, int oif, struct net_device *dev,
304 struct in_device *idev, u32 *itag);
305 void fib_select_default(const struct flowi4 *flp, struct fib_result *res);
306 #ifdef CONFIG_IP_ROUTE_CLASSID
307 static inline int fib_num_tclassid_users(struct net *net)
309 return net->ipv4.fib_num_tclassid_users;
312 static inline int fib_num_tclassid_users(struct net *net)
317 int fib_unmerge(struct net *net);
318 void fib_flush_external(struct net *net);
320 /* Exported by fib_semantics.c */
321 int ip_fib_check_default(__be32 gw, struct net_device *dev);
322 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
323 int fib_sync_down_addr(struct net_device *dev, __be32 local);
324 int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
326 extern u32 fib_multipath_secret __read_mostly;
328 static inline int fib_multipath_hash(__be32 saddr, __be32 daddr)
330 return jhash_2words((__force u32)saddr, (__force u32)daddr,
331 fib_multipath_secret) >> 1;
334 void fib_select_multipath(struct fib_result *res, int hash);
335 void fib_select_path(struct net *net, struct fib_result *res,
336 struct flowi4 *fl4, int mp_hash);
338 /* Exported by fib_trie.c */
339 void fib_trie_init(void);
340 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
342 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
344 #ifdef CONFIG_IP_ROUTE_CLASSID
345 #ifdef CONFIG_IP_MULTIPLE_TABLES
348 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
349 #ifdef CONFIG_IP_MULTIPLE_TABLES
350 rtag = res->tclassid;
358 void free_fib_info(struct fib_info *fi);
360 static inline void fib_info_put(struct fib_info *fi)
362 if (atomic_dec_and_test(&fi->fib_clntref))
366 #ifdef CONFIG_PROC_FS
367 int __net_init fib_proc_init(struct net *net);
368 void __net_exit fib_proc_exit(struct net *net);
370 static inline int fib_proc_init(struct net *net)
374 static inline void fib_proc_exit(struct net *net)
379 #endif /* _NET_FIB_H */