1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Definitions for the Forwarding Information Base.
9 * Authors: A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
16 #include <linux/seq_file.h>
17 #include <linux/rcupdate.h>
18 #include <net/fib_notifier.h>
19 #include <net/fib_rules.h>
20 #include <net/inetpeer.h>
21 #include <linux/percpu.h>
22 #include <linux/notifier.h>
23 #include <linux/refcount.h>
37 struct in6_addr fc_gw6;
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 char nhc_scope;
85 unsigned char nhc_flags;
86 struct lwtunnel_state *nhc_lwtstate;
94 atomic_t nhc_upper_bound;
96 /* v4 specific, but allows fib6_nh with v4 routes */
97 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
98 struct rtable __rcu *nhc_rth_input;
99 struct fnhe_hash_bucket __rcu *nhc_exceptions;
103 struct fib_nh_common nh_common;
104 struct hlist_node nh_hash;
105 struct fib_info *nh_parent;
106 #ifdef CONFIG_IP_ROUTE_CLASSID
111 #define fib_nh_family nh_common.nhc_family
112 #define fib_nh_dev nh_common.nhc_dev
113 #define fib_nh_oif nh_common.nhc_oif
114 #define fib_nh_flags nh_common.nhc_flags
115 #define fib_nh_lws nh_common.nhc_lwtstate
116 #define fib_nh_scope nh_common.nhc_scope
117 #define fib_nh_gw_family nh_common.nhc_gw_family
118 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
119 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
120 #define fib_nh_weight nh_common.nhc_weight
121 #define fib_nh_upper_bound nh_common.nhc_upper_bound
125 * This structure contains data shared by many of routes.
129 struct hlist_node fib_hash;
130 struct hlist_node fib_lhash;
133 refcount_t fib_clntref;
134 unsigned int fib_flags;
135 unsigned char fib_dead;
136 unsigned char fib_protocol;
137 unsigned char fib_scope;
138 unsigned char fib_type;
142 struct dst_metrics *fib_metrics;
143 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
144 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
145 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
146 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
150 struct fib_nh fib_nh[0];
151 #define fib_dev fib_nh[0].fib_nh_dev
155 #ifdef CONFIG_IP_MULTIPLE_TABLES
162 unsigned char prefixlen;
163 unsigned char nh_sel;
167 struct fib_nh_common *nhc;
169 struct fib_table *table;
170 struct hlist_head *fa_head;
173 struct fib_result_nl {
174 __be32 fl_addr; /* To be looked up*/
176 unsigned char fl_tos;
177 unsigned char fl_scope;
178 unsigned char tb_id_in;
180 unsigned char tb_id; /* Results */
181 unsigned char prefixlen;
182 unsigned char nh_sel;
188 static inline struct fib_nh_common *fib_info_nhc(struct fib_info *fi, int nhsel)
190 return &fi->fib_nh[nhsel].nh_common;
193 #ifdef CONFIG_IP_MULTIPLE_TABLES
194 #define FIB_TABLE_HASHSZ 256
196 #define FIB_TABLE_HASHSZ 2
199 __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
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_notify(struct net *net, struct notifier_block *nb);
233 struct hlist_node tb_hlist;
237 unsigned long *tb_data;
238 unsigned long __data[0];
241 struct fib_dump_filter {
243 /* filter_set is an optimization that an entry is set */
245 bool dump_all_families;
246 unsigned char protocol;
247 unsigned char rt_type;
249 struct net_device *dev;
252 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
253 struct fib_result *res, int fib_flags);
254 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
255 struct netlink_ext_ack *extack);
256 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
257 struct netlink_ext_ack *extack);
258 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
259 struct netlink_callback *cb, struct fib_dump_filter *filter);
260 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
261 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
262 void fib_table_flush_external(struct fib_table *table);
263 void fib_free_table(struct fib_table *tb);
265 #ifndef CONFIG_IP_MULTIPLE_TABLES
267 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
268 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
270 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
272 struct hlist_node *tb_hlist;
273 struct hlist_head *ptr;
275 ptr = id == RT_TABLE_LOCAL ?
276 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
277 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
279 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
281 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
284 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
286 return fib_get_table(net, id);
289 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
290 struct fib_result *res, unsigned int flags)
292 struct fib_table *tb;
293 int err = -ENETUNREACH;
297 tb = fib_get_table(net, RT_TABLE_MAIN);
299 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
309 static inline bool fib4_rule_default(const struct fib_rule *rule)
314 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
319 static inline unsigned int fib4_rules_seq_read(struct net *net)
324 static inline bool fib4_rules_early_flow_dissect(struct net *net,
327 struct flow_keys *flkeys)
331 #else /* CONFIG_IP_MULTIPLE_TABLES */
332 int __net_init fib4_rules_init(struct net *net);
333 void __net_exit fib4_rules_exit(struct net *net);
335 struct fib_table *fib_new_table(struct net *net, u32 id);
336 struct fib_table *fib_get_table(struct net *net, u32 id);
338 int __fib_lookup(struct net *net, struct flowi4 *flp,
339 struct fib_result *res, unsigned int flags);
341 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
342 struct fib_result *res, unsigned int flags)
344 struct fib_table *tb;
345 int err = -ENETUNREACH;
347 flags |= FIB_LOOKUP_NOREF;
348 if (net->ipv4.fib_has_custom_rules)
349 return __fib_lookup(net, flp, res, flags);
355 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
357 err = fib_table_lookup(tb, flp, res, flags);
362 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
364 err = fib_table_lookup(tb, flp, res, flags);
375 bool fib4_rule_default(const struct fib_rule *rule);
376 int fib4_rules_dump(struct net *net, struct notifier_block *nb);
377 unsigned int fib4_rules_seq_read(struct net *net);
379 static inline bool fib4_rules_early_flow_dissect(struct net *net,
382 struct flow_keys *flkeys)
384 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
386 if (!net->ipv4.fib_rules_require_fldissect)
389 skb_flow_dissect_flow_keys(skb, flkeys, flag);
390 fl4->fl4_sport = flkeys->ports.src;
391 fl4->fl4_dport = flkeys->ports.dst;
392 fl4->flowi4_proto = flkeys->basic.ip_proto;
397 #endif /* CONFIG_IP_MULTIPLE_TABLES */
399 /* Exported by fib_frontend.c */
400 extern const struct nla_policy rtm_ipv4_policy[];
401 void ip_fib_init(void);
402 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
403 struct netlink_ext_ack *extack);
404 __be32 fib_compute_spec_dst(struct sk_buff *skb);
405 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
406 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
407 u8 tos, int oif, struct net_device *dev,
408 struct in_device *idev, u32 *itag);
409 #ifdef CONFIG_IP_ROUTE_CLASSID
410 static inline int fib_num_tclassid_users(struct net *net)
412 return net->ipv4.fib_num_tclassid_users;
415 static inline int fib_num_tclassid_users(struct net *net)
420 int fib_unmerge(struct net *net);
422 /* Exported by fib_semantics.c */
423 int ip_fib_check_default(__be32 gw, struct net_device *dev);
424 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
425 int fib_sync_down_addr(struct net_device *dev, __be32 local);
426 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
427 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
429 #ifdef CONFIG_IP_ROUTE_MULTIPATH
430 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
431 const struct sk_buff *skb, struct flow_keys *flkeys);
433 void fib_select_multipath(struct fib_result *res, int hash);
434 void fib_select_path(struct net *net, struct fib_result *res,
435 struct flowi4 *fl4, const struct sk_buff *skb);
437 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
438 struct fib_config *cfg, int nh_weight,
439 struct netlink_ext_ack *extack);
440 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
441 int fib_nh_common_init(struct fib_nh_common *nhc, struct nlattr *fc_encap,
442 u16 fc_encap_type, void *cfg, gfp_t gfp_flags,
443 struct netlink_ext_ack *extack);
444 void fib_nh_common_release(struct fib_nh_common *nhc);
446 /* Exported by fib_trie.c */
447 void fib_trie_init(void);
448 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
450 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
452 #ifdef CONFIG_IP_ROUTE_CLASSID
453 struct fib_nh_common *nhc = res->nhc;
454 struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
455 #ifdef CONFIG_IP_MULTIPLE_TABLES
458 *itag = nh->nh_tclassid << 16;
459 #ifdef CONFIG_IP_MULTIPLE_TABLES
460 rtag = res->tclassid;
468 void free_fib_info(struct fib_info *fi);
470 static inline void fib_info_hold(struct fib_info *fi)
472 refcount_inc(&fi->fib_clntref);
475 static inline void fib_info_put(struct fib_info *fi)
477 if (refcount_dec_and_test(&fi->fib_clntref))
481 #ifdef CONFIG_PROC_FS
482 int __net_init fib_proc_init(struct net *net);
483 void __net_exit fib_proc_exit(struct net *net);
485 static inline int fib_proc_init(struct net *net)
489 static inline void fib_proc_exit(struct net *net)
494 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
496 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
497 struct fib_dump_filter *filter,
498 struct netlink_callback *cb);
500 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
501 unsigned char *flags, bool skip_oif);
502 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
504 #endif /* _NET_FIB_H */