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>
41 struct in6_addr fc_gw6;
48 struct rtnexthop *fc_mp;
53 struct nl_info fc_nlinfo;
54 struct nlattr *fc_encap;
61 struct fib_nh_exception {
62 struct fib_nh_exception __rcu *fnhe_next;
68 unsigned long fnhe_expires;
69 struct rtable __rcu *fnhe_rth_input;
70 struct rtable __rcu *fnhe_rth_output;
71 unsigned long fnhe_stamp;
75 struct fnhe_hash_bucket {
76 struct fib_nh_exception __rcu *chain;
79 #define FNHE_HASH_SHIFT 11
80 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
81 #define FNHE_RECLAIM_DEPTH 5
83 struct fib_nh_common {
84 struct net_device *nhc_dev;
86 unsigned char nhc_scope;
89 unsigned char nhc_flags;
90 struct lwtunnel_state *nhc_lwtstate;
98 atomic_t nhc_upper_bound;
100 /* v4 specific, but allows fib6_nh with v4 routes */
101 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
102 struct rtable __rcu *nhc_rth_input;
103 struct fnhe_hash_bucket __rcu *nhc_exceptions;
107 struct fib_nh_common nh_common;
108 struct hlist_node nh_hash;
109 struct fib_info *nh_parent;
110 #ifdef CONFIG_IP_ROUTE_CLASSID
115 #define fib_nh_family nh_common.nhc_family
116 #define fib_nh_dev nh_common.nhc_dev
117 #define fib_nh_oif nh_common.nhc_oif
118 #define fib_nh_flags nh_common.nhc_flags
119 #define fib_nh_lws nh_common.nhc_lwtstate
120 #define fib_nh_scope nh_common.nhc_scope
121 #define fib_nh_gw_family nh_common.nhc_gw_family
122 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
123 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
124 #define fib_nh_weight nh_common.nhc_weight
125 #define fib_nh_upper_bound nh_common.nhc_upper_bound
129 * This structure contains data shared by many of routes.
133 struct hlist_node fib_hash;
134 struct hlist_node fib_lhash;
137 refcount_t fib_clntref;
138 unsigned int fib_flags;
139 unsigned char fib_dead;
140 unsigned char fib_protocol;
141 unsigned char fib_scope;
142 unsigned char fib_type;
146 struct dst_metrics *fib_metrics;
147 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
148 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
149 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
150 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
155 struct fib_nh fib_nh[0];
159 #ifdef CONFIG_IP_MULTIPLE_TABLES
166 unsigned char prefixlen;
167 unsigned char nh_sel;
171 struct fib_nh_common *nhc;
173 struct fib_table *table;
174 struct hlist_head *fa_head;
177 struct fib_result_nl {
178 __be32 fl_addr; /* To be looked up*/
180 unsigned char fl_tos;
181 unsigned char fl_scope;
182 unsigned char tb_id_in;
184 unsigned char tb_id; /* Results */
185 unsigned char prefixlen;
186 unsigned char nh_sel;
192 #ifdef CONFIG_IP_MULTIPLE_TABLES
193 #define FIB_TABLE_HASHSZ 256
195 #define FIB_TABLE_HASHSZ 2
198 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh,
199 unsigned char scope);
200 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
202 #define FIB_RES_NHC(res) ((res).nhc)
203 #define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
204 #define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
206 struct fib_entry_notifier_info {
207 struct fib_notifier_info info; /* must be first */
216 struct fib_nh_notifier_info {
217 struct fib_notifier_info info; /* must be first */
218 struct fib_nh *fib_nh;
221 int call_fib4_notifier(struct notifier_block *nb, struct net *net,
222 enum fib_event_type event_type,
223 struct fib_notifier_info *info);
224 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
225 struct fib_notifier_info *info);
227 int __net_init fib4_notifier_init(struct net *net);
228 void __net_exit fib4_notifier_exit(struct net *net);
230 void fib_info_notify_update(struct net *net, struct nl_info *info);
231 void fib_notify(struct net *net, struct notifier_block *nb);
234 struct hlist_node tb_hlist;
238 unsigned long *tb_data;
239 unsigned long __data[0];
242 struct fib_dump_filter {
244 /* filter_set is an optimization that an entry is set */
246 bool dump_all_families;
247 unsigned char protocol;
248 unsigned char rt_type;
250 struct net_device *dev;
253 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
254 struct fib_result *res, int fib_flags);
255 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
256 struct netlink_ext_ack *extack);
257 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
258 struct netlink_ext_ack *extack);
259 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
260 struct netlink_callback *cb, struct fib_dump_filter *filter);
261 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
262 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
263 void fib_table_flush_external(struct fib_table *table);
264 void fib_free_table(struct fib_table *tb);
266 #ifndef CONFIG_IP_MULTIPLE_TABLES
268 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
269 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
271 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
273 struct hlist_node *tb_hlist;
274 struct hlist_head *ptr;
276 ptr = id == RT_TABLE_LOCAL ?
277 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
278 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
280 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
282 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
285 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
287 return fib_get_table(net, id);
290 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
291 struct fib_result *res, unsigned int flags)
293 struct fib_table *tb;
294 int err = -ENETUNREACH;
298 tb = fib_get_table(net, RT_TABLE_MAIN);
300 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
310 static inline bool fib4_rule_default(const struct fib_rule *rule)
315 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
320 static inline unsigned int fib4_rules_seq_read(struct net *net)
325 static inline bool fib4_rules_early_flow_dissect(struct net *net,
328 struct flow_keys *flkeys)
332 #else /* CONFIG_IP_MULTIPLE_TABLES */
333 int __net_init fib4_rules_init(struct net *net);
334 void __net_exit fib4_rules_exit(struct net *net);
336 struct fib_table *fib_new_table(struct net *net, u32 id);
337 struct fib_table *fib_get_table(struct net *net, u32 id);
339 int __fib_lookup(struct net *net, struct flowi4 *flp,
340 struct fib_result *res, unsigned int flags);
342 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
343 struct fib_result *res, unsigned int flags)
345 struct fib_table *tb;
346 int err = -ENETUNREACH;
348 flags |= FIB_LOOKUP_NOREF;
349 if (net->ipv4.fib_has_custom_rules)
350 return __fib_lookup(net, flp, res, flags);
356 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
358 err = fib_table_lookup(tb, flp, res, flags);
363 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
365 err = fib_table_lookup(tb, flp, res, flags);
376 bool fib4_rule_default(const struct fib_rule *rule);
377 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
378 unsigned int fib4_rules_seq_read(struct net *net);
380 static inline bool fib4_rules_early_flow_dissect(struct net *net,
383 struct flow_keys *flkeys)
385 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
387 if (!net->ipv4.fib_rules_require_fldissect)
390 skb_flow_dissect_flow_keys(skb, flkeys, flag);
391 fl4->fl4_sport = flkeys->ports.src;
392 fl4->fl4_dport = flkeys->ports.dst;
393 fl4->flowi4_proto = flkeys->basic.ip_proto;
398 #endif /* CONFIG_IP_MULTIPLE_TABLES */
400 /* Exported by fib_frontend.c */
401 extern const struct nla_policy rtm_ipv4_policy[];
402 void ip_fib_init(void);
403 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
404 struct netlink_ext_ack *extack);
405 __be32 fib_compute_spec_dst(struct sk_buff *skb);
406 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
407 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
408 u8 tos, int oif, struct net_device *dev,
409 struct in_device *idev, u32 *itag);
410 #ifdef CONFIG_IP_ROUTE_CLASSID
411 static inline int fib_num_tclassid_users(struct net *net)
413 return net->ipv4.fib_num_tclassid_users;
416 static inline int fib_num_tclassid_users(struct net *net)
421 int fib_unmerge(struct net *net);
423 /* Exported by fib_semantics.c */
424 int ip_fib_check_default(__be32 gw, struct net_device *dev);
425 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
426 int fib_sync_down_addr(struct net_device *dev, __be32 local);
427 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
428 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
429 void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
431 #ifdef CONFIG_IP_ROUTE_MULTIPATH
432 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
433 const struct sk_buff *skb, struct flow_keys *flkeys);
435 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
436 struct netlink_ext_ack *extack);
437 void fib_select_multipath(struct fib_result *res, int hash);
438 void fib_select_path(struct net *net, struct fib_result *res,
439 struct flowi4 *fl4, const struct sk_buff *skb);
441 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
442 struct fib_config *cfg, int nh_weight,
443 struct netlink_ext_ack *extack);
444 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
445 int fib_nh_common_init(struct fib_nh_common *nhc, struct nlattr *fc_encap,
446 u16 fc_encap_type, void *cfg, gfp_t gfp_flags,
447 struct netlink_ext_ack *extack);
448 void fib_nh_common_release(struct fib_nh_common *nhc);
450 /* Exported by fib_trie.c */
451 void fib_trie_init(void);
452 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
454 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
456 #ifdef CONFIG_IP_ROUTE_CLASSID
457 struct fib_nh_common *nhc = res->nhc;
458 struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
459 #ifdef CONFIG_IP_MULTIPLE_TABLES
462 *itag = nh->nh_tclassid << 16;
463 #ifdef CONFIG_IP_MULTIPLE_TABLES
464 rtag = res->tclassid;
472 void fib_flush(struct net *net);
473 void free_fib_info(struct fib_info *fi);
475 static inline void fib_info_hold(struct fib_info *fi)
477 refcount_inc(&fi->fib_clntref);
480 static inline void fib_info_put(struct fib_info *fi)
482 if (refcount_dec_and_test(&fi->fib_clntref))
486 #ifdef CONFIG_PROC_FS
487 int __net_init fib_proc_init(struct net *net);
488 void __net_exit fib_proc_exit(struct net *net);
490 static inline int fib_proc_init(struct net *net)
494 static inline void fib_proc_exit(struct net *net)
499 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
501 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
502 struct fib_dump_filter *filter,
503 struct netlink_callback *cb);
505 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
506 unsigned char *flags, bool skip_oif);
507 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
509 #endif /* _NET_FIB_H */