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;
64 unsigned long fnhe_expires;
65 struct rtable __rcu *fnhe_rth_input;
66 struct rtable __rcu *fnhe_rth_output;
67 unsigned long fnhe_stamp;
71 struct fnhe_hash_bucket {
72 struct fib_nh_exception __rcu *chain;
75 #define FNHE_HASH_SHIFT 11
76 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
77 #define FNHE_RECLAIM_DEPTH 5
79 struct fib_nh_common {
80 struct net_device *nhc_dev;
82 unsigned int nhc_flags;
83 struct lwtunnel_state *nhc_lwtstate;
84 unsigned char nhc_scope;
94 atomic_t nhc_upper_bound;
98 struct fib_nh_common nh_common;
99 struct hlist_node nh_hash;
100 struct fib_info *nh_parent;
101 #ifdef CONFIG_IP_ROUTE_CLASSID
106 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
107 struct rtable __rcu *nh_rth_input;
108 struct fnhe_hash_bucket __rcu *nh_exceptions;
109 #define fib_nh_family nh_common.nhc_family
110 #define fib_nh_dev nh_common.nhc_dev
111 #define fib_nh_oif nh_common.nhc_oif
112 #define fib_nh_flags nh_common.nhc_flags
113 #define fib_nh_lws nh_common.nhc_lwtstate
114 #define fib_nh_scope nh_common.nhc_scope
115 #define fib_nh_family nh_common.nhc_family
116 #define fib_nh_has_gw nh_common.nhc_has_gw
117 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
118 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
119 #define fib_nh_weight nh_common.nhc_weight
120 #define fib_nh_upper_bound nh_common.nhc_upper_bound
124 * This structure contains data shared by many of routes.
128 struct hlist_node fib_hash;
129 struct hlist_node fib_lhash;
132 refcount_t fib_clntref;
133 unsigned int fib_flags;
134 unsigned char fib_dead;
135 unsigned char fib_protocol;
136 unsigned char fib_scope;
137 unsigned char fib_type;
141 struct dst_metrics *fib_metrics;
142 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
143 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
144 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
145 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
148 struct fib_nh fib_nh[0];
149 #define fib_dev fib_nh[0].fib_nh_dev
153 #ifdef CONFIG_IP_MULTIPLE_TABLES
160 unsigned char prefixlen;
161 unsigned char nh_sel;
166 struct fib_table *table;
167 struct hlist_head *fa_head;
170 struct fib_result_nl {
171 __be32 fl_addr; /* To be looked up*/
173 unsigned char fl_tos;
174 unsigned char fl_scope;
175 unsigned char tb_id_in;
177 unsigned char tb_id; /* Results */
178 unsigned char prefixlen;
179 unsigned char nh_sel;
185 #ifdef CONFIG_IP_ROUTE_MULTIPATH
186 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
187 #else /* CONFIG_IP_ROUTE_MULTIPATH */
188 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
189 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
191 #ifdef CONFIG_IP_MULTIPLE_TABLES
192 #define FIB_TABLE_HASHSZ 256
194 #define FIB_TABLE_HASHSZ 2
197 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
199 #define FIB_RES_SADDR(net, res) \
200 ((FIB_RES_NH(res).nh_saddr_genid == \
201 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
202 FIB_RES_NH(res).nh_saddr : \
203 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
204 #define FIB_RES_GW(res) (FIB_RES_NH(res).fib_nh_gw4)
205 #define FIB_RES_DEV(res) (FIB_RES_NH(res).fib_nh_dev)
206 #define FIB_RES_OIF(res) (FIB_RES_NH(res).fib_nh_oif)
208 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
209 FIB_RES_SADDR(net, res))
211 struct fib_entry_notifier_info {
212 struct fib_notifier_info info; /* must be first */
221 struct fib_nh_notifier_info {
222 struct fib_notifier_info info; /* must be first */
223 struct fib_nh *fib_nh;
226 int call_fib4_notifier(struct notifier_block *nb, struct net *net,
227 enum fib_event_type event_type,
228 struct fib_notifier_info *info);
229 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
230 struct fib_notifier_info *info);
232 int __net_init fib4_notifier_init(struct net *net);
233 void __net_exit fib4_notifier_exit(struct net *net);
235 void fib_notify(struct net *net, struct notifier_block *nb);
238 struct hlist_node tb_hlist;
242 unsigned long *tb_data;
243 unsigned long __data[0];
246 struct fib_dump_filter {
248 /* filter_set is an optimization that an entry is set */
250 bool dump_all_families;
251 unsigned char protocol;
252 unsigned char rt_type;
254 struct net_device *dev;
257 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
258 struct fib_result *res, int fib_flags);
259 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
260 struct netlink_ext_ack *extack);
261 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
262 struct netlink_ext_ack *extack);
263 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
264 struct netlink_callback *cb, struct fib_dump_filter *filter);
265 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
266 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
267 void fib_table_flush_external(struct fib_table *table);
268 void fib_free_table(struct fib_table *tb);
270 #ifndef CONFIG_IP_MULTIPLE_TABLES
272 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
273 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
275 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
277 struct hlist_node *tb_hlist;
278 struct hlist_head *ptr;
280 ptr = id == RT_TABLE_LOCAL ?
281 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
282 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
284 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
286 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
289 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
291 return fib_get_table(net, id);
294 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
295 struct fib_result *res, unsigned int flags)
297 struct fib_table *tb;
298 int err = -ENETUNREACH;
302 tb = fib_get_table(net, RT_TABLE_MAIN);
304 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
314 static inline bool fib4_rule_default(const struct fib_rule *rule)
319 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
324 static inline unsigned int fib4_rules_seq_read(struct net *net)
329 static inline bool fib4_rules_early_flow_dissect(struct net *net,
332 struct flow_keys *flkeys)
336 #else /* CONFIG_IP_MULTIPLE_TABLES */
337 int __net_init fib4_rules_init(struct net *net);
338 void __net_exit fib4_rules_exit(struct net *net);
340 struct fib_table *fib_new_table(struct net *net, u32 id);
341 struct fib_table *fib_get_table(struct net *net, u32 id);
343 int __fib_lookup(struct net *net, struct flowi4 *flp,
344 struct fib_result *res, unsigned int flags);
346 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
347 struct fib_result *res, unsigned int flags)
349 struct fib_table *tb;
350 int err = -ENETUNREACH;
352 flags |= FIB_LOOKUP_NOREF;
353 if (net->ipv4.fib_has_custom_rules)
354 return __fib_lookup(net, flp, res, flags);
360 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
362 err = fib_table_lookup(tb, flp, res, flags);
367 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
369 err = fib_table_lookup(tb, flp, res, flags);
380 bool fib4_rule_default(const struct fib_rule *rule);
381 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
382 unsigned int fib4_rules_seq_read(struct net *net);
384 static inline bool fib4_rules_early_flow_dissect(struct net *net,
387 struct flow_keys *flkeys)
389 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
391 if (!net->ipv4.fib_rules_require_fldissect)
394 skb_flow_dissect_flow_keys(skb, flkeys, flag);
395 fl4->fl4_sport = flkeys->ports.src;
396 fl4->fl4_dport = flkeys->ports.dst;
397 fl4->flowi4_proto = flkeys->basic.ip_proto;
402 #endif /* CONFIG_IP_MULTIPLE_TABLES */
404 /* Exported by fib_frontend.c */
405 extern const struct nla_policy rtm_ipv4_policy[];
406 void ip_fib_init(void);
407 __be32 fib_compute_spec_dst(struct sk_buff *skb);
408 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
409 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
410 u8 tos, int oif, struct net_device *dev,
411 struct in_device *idev, u32 *itag);
412 #ifdef CONFIG_IP_ROUTE_CLASSID
413 static inline int fib_num_tclassid_users(struct net *net)
415 return net->ipv4.fib_num_tclassid_users;
418 static inline int fib_num_tclassid_users(struct net *net)
423 int fib_unmerge(struct net *net);
425 /* Exported by fib_semantics.c */
426 int ip_fib_check_default(__be32 gw, struct net_device *dev);
427 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
428 int fib_sync_down_addr(struct net_device *dev, __be32 local);
429 int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
430 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
432 #ifdef CONFIG_IP_ROUTE_MULTIPATH
433 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
434 const struct sk_buff *skb, struct flow_keys *flkeys);
436 void fib_select_multipath(struct fib_result *res, int hash);
437 void fib_select_path(struct net *net, struct fib_result *res,
438 struct flowi4 *fl4, const struct sk_buff *skb);
440 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
441 struct fib_config *cfg, int nh_weight,
442 struct netlink_ext_ack *extack);
443 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
445 /* Exported by fib_trie.c */
446 void fib_trie_init(void);
447 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
449 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
451 #ifdef CONFIG_IP_ROUTE_CLASSID
452 #ifdef CONFIG_IP_MULTIPLE_TABLES
455 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
456 #ifdef CONFIG_IP_MULTIPLE_TABLES
457 rtag = res->tclassid;
465 void free_fib_info(struct fib_info *fi);
467 static inline void fib_info_hold(struct fib_info *fi)
469 refcount_inc(&fi->fib_clntref);
472 static inline void fib_info_put(struct fib_info *fi)
474 if (refcount_dec_and_test(&fi->fib_clntref))
478 #ifdef CONFIG_PROC_FS
479 int __net_init fib_proc_init(struct net *net);
480 void __net_exit fib_proc_exit(struct net *net);
482 static inline int fib_proc_init(struct net *net)
486 static inline void fib_proc_exit(struct net *net)
491 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
493 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
494 struct fib_dump_filter *filter,
495 struct netlink_callback *cb);
496 #endif /* _NET_FIB_H */