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;
45 struct rtnexthop *fc_mp;
50 struct nl_info fc_nlinfo;
51 struct nlattr *fc_encap;
58 struct fib_nh_exception {
59 struct fib_nh_exception __rcu *fnhe_next;
65 unsigned long fnhe_expires;
66 struct rtable __rcu *fnhe_rth_input;
67 struct rtable __rcu *fnhe_rth_output;
68 unsigned long fnhe_stamp;
72 struct fnhe_hash_bucket {
73 struct fib_nh_exception __rcu *chain;
76 #define FNHE_HASH_SHIFT 11
77 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
78 #define FNHE_RECLAIM_DEPTH 5
80 struct fib_nh_common {
81 struct net_device *nhc_dev;
82 netdevice_tracker nhc_dev_tracker;
84 unsigned char nhc_scope;
87 unsigned char nhc_flags;
88 struct lwtunnel_state *nhc_lwtstate;
96 atomic_t nhc_upper_bound;
98 /* v4 specific, but allows fib6_nh with v4 routes */
99 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
100 struct rtable __rcu *nhc_rth_input;
101 struct fnhe_hash_bucket __rcu *nhc_exceptions;
105 struct fib_nh_common nh_common;
106 struct hlist_node nh_hash;
107 struct fib_info *nh_parent;
108 #ifdef CONFIG_IP_ROUTE_CLASSID
113 #define fib_nh_family nh_common.nhc_family
114 #define fib_nh_dev nh_common.nhc_dev
115 #define fib_nh_dev_tracker nh_common.nhc_dev_tracker
116 #define fib_nh_oif nh_common.nhc_oif
117 #define fib_nh_flags nh_common.nhc_flags
118 #define fib_nh_lws nh_common.nhc_lwtstate
119 #define fib_nh_scope nh_common.nhc_scope
120 #define fib_nh_gw_family nh_common.nhc_gw_family
121 #define fib_nh_gw4 nh_common.nhc_gw.ipv4
122 #define fib_nh_gw6 nh_common.nhc_gw.ipv6
123 #define fib_nh_weight nh_common.nhc_weight
124 #define fib_nh_upper_bound nh_common.nhc_upper_bound
128 * This structure contains data shared by many of routes.
134 struct hlist_node fib_hash;
135 struct hlist_node fib_lhash;
136 struct list_head nh_list;
138 refcount_t fib_treeref;
139 refcount_t fib_clntref;
140 unsigned int fib_flags;
141 unsigned char fib_dead;
142 unsigned char fib_protocol;
143 unsigned char fib_scope;
144 unsigned char fib_type;
148 struct dst_metrics *fib_metrics;
149 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
150 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
151 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
152 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
158 struct fib_nh fib_nh[];
162 #ifdef CONFIG_IP_MULTIPLE_TABLES
169 unsigned char prefixlen;
170 unsigned char nh_sel;
174 struct fib_nh_common *nhc;
176 struct fib_table *table;
177 struct hlist_head *fa_head;
180 struct fib_result_nl {
181 __be32 fl_addr; /* To be looked up*/
183 unsigned char fl_tos;
184 unsigned char fl_scope;
185 unsigned char tb_id_in;
187 unsigned char tb_id; /* Results */
188 unsigned char prefixlen;
189 unsigned char nh_sel;
195 #ifdef CONFIG_IP_MULTIPLE_TABLES
196 #define FIB_TABLE_HASHSZ 256
198 #define FIB_TABLE_HASHSZ 2
201 __be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
202 unsigned char scope);
203 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
205 #define FIB_RES_NHC(res) ((res).nhc)
206 #define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
207 #define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
222 struct fib_entry_notifier_info {
223 struct fib_notifier_info info; /* must be first */
232 struct fib_nh_notifier_info {
233 struct fib_notifier_info info; /* must be first */
234 struct fib_nh *fib_nh;
237 int call_fib4_notifier(struct notifier_block *nb,
238 enum fib_event_type event_type,
239 struct fib_notifier_info *info);
240 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
241 struct fib_notifier_info *info);
243 int __net_init fib4_notifier_init(struct net *net);
244 void __net_exit fib4_notifier_exit(struct net *net);
246 void fib_info_notify_update(struct net *net, struct nl_info *info);
247 int fib_notify(struct net *net, struct notifier_block *nb,
248 struct netlink_ext_ack *extack);
251 struct hlist_node tb_hlist;
255 unsigned long *tb_data;
256 unsigned long __data[];
259 struct fib_dump_filter {
261 /* filter_set is an optimization that an entry is set */
264 bool dump_exceptions;
265 unsigned char protocol;
266 unsigned char rt_type;
268 struct net_device *dev;
271 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
272 struct fib_result *res, int fib_flags);
273 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
274 struct netlink_ext_ack *extack);
275 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
276 struct netlink_ext_ack *extack);
277 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
278 struct netlink_callback *cb, struct fib_dump_filter *filter);
279 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
280 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
281 void fib_table_flush_external(struct fib_table *table);
282 void fib_free_table(struct fib_table *tb);
284 #ifndef CONFIG_IP_MULTIPLE_TABLES
286 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
287 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
289 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
291 struct hlist_node *tb_hlist;
292 struct hlist_head *ptr;
294 ptr = id == RT_TABLE_LOCAL ?
295 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
296 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
298 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
300 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
303 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
305 return fib_get_table(net, id);
308 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
309 struct fib_result *res, unsigned int flags)
311 struct fib_table *tb;
312 int err = -ENETUNREACH;
316 tb = fib_get_table(net, RT_TABLE_MAIN);
318 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
328 static inline bool fib4_has_custom_rules(const struct net *net)
333 static inline bool fib4_rule_default(const struct fib_rule *rule)
338 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
339 struct netlink_ext_ack *extack)
344 static inline unsigned int fib4_rules_seq_read(struct net *net)
349 static inline bool fib4_rules_early_flow_dissect(struct net *net,
352 struct flow_keys *flkeys)
356 #else /* CONFIG_IP_MULTIPLE_TABLES */
357 int __net_init fib4_rules_init(struct net *net);
358 void __net_exit fib4_rules_exit(struct net *net);
360 struct fib_table *fib_new_table(struct net *net, u32 id);
361 struct fib_table *fib_get_table(struct net *net, u32 id);
363 int __fib_lookup(struct net *net, struct flowi4 *flp,
364 struct fib_result *res, unsigned int flags);
366 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
367 struct fib_result *res, unsigned int flags)
369 struct fib_table *tb;
370 int err = -ENETUNREACH;
372 flags |= FIB_LOOKUP_NOREF;
373 if (net->ipv4.fib_has_custom_rules)
374 return __fib_lookup(net, flp, res, flags);
380 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
382 err = fib_table_lookup(tb, flp, res, flags);
387 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
389 err = fib_table_lookup(tb, flp, res, flags);
400 static inline bool fib4_has_custom_rules(const struct net *net)
402 return net->ipv4.fib_has_custom_rules;
405 bool fib4_rule_default(const struct fib_rule *rule);
406 int fib4_rules_dump(struct net *net, struct notifier_block *nb,
407 struct netlink_ext_ack *extack);
408 unsigned int fib4_rules_seq_read(struct net *net);
410 static inline bool fib4_rules_early_flow_dissect(struct net *net,
413 struct flow_keys *flkeys)
415 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
417 if (!net->ipv4.fib_rules_require_fldissect)
420 skb_flow_dissect_flow_keys(skb, flkeys, flag);
421 fl4->fl4_sport = flkeys->ports.src;
422 fl4->fl4_dport = flkeys->ports.dst;
423 fl4->flowi4_proto = flkeys->basic.ip_proto;
428 #endif /* CONFIG_IP_MULTIPLE_TABLES */
430 /* Exported by fib_frontend.c */
431 extern const struct nla_policy rtm_ipv4_policy[];
432 void ip_fib_init(void);
433 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
434 struct netlink_ext_ack *extack);
435 __be32 fib_compute_spec_dst(struct sk_buff *skb);
436 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
437 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
438 u8 tos, int oif, struct net_device *dev,
439 struct in_device *idev, u32 *itag);
440 #ifdef CONFIG_IP_ROUTE_CLASSID
441 static inline int fib_num_tclassid_users(struct net *net)
443 return atomic_read(&net->ipv4.fib_num_tclassid_users);
446 static inline int fib_num_tclassid_users(struct net *net)
451 int fib_unmerge(struct net *net);
453 static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
454 const struct net_device *dev)
456 if (nhc->nhc_dev == dev ||
457 l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
463 /* Exported by fib_semantics.c */
464 int ip_fib_check_default(__be32 gw, struct net_device *dev);
465 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
466 int fib_sync_down_addr(struct net_device *dev, __be32 local);
467 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
468 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
469 void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
471 /* Fields used for sysctl_fib_multipath_hash_fields.
472 * Common to IPv4 and IPv6.
474 * Add new fields at the end. This is user API.
476 #define FIB_MULTIPATH_HASH_FIELD_SRC_IP BIT(0)
477 #define FIB_MULTIPATH_HASH_FIELD_DST_IP BIT(1)
478 #define FIB_MULTIPATH_HASH_FIELD_IP_PROTO BIT(2)
479 #define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL BIT(3)
480 #define FIB_MULTIPATH_HASH_FIELD_SRC_PORT BIT(4)
481 #define FIB_MULTIPATH_HASH_FIELD_DST_PORT BIT(5)
482 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP BIT(6)
483 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP BIT(7)
484 #define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO BIT(8)
485 #define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL BIT(9)
486 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT BIT(10)
487 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT BIT(11)
489 #define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK \
490 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
491 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
492 FIB_MULTIPATH_HASH_FIELD_IP_PROTO | \
493 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL | \
494 FIB_MULTIPATH_HASH_FIELD_SRC_PORT | \
495 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
497 #define FIB_MULTIPATH_HASH_FIELD_INNER_MASK \
498 (FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP | \
499 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP | \
500 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO | \
501 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL | \
502 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT | \
503 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
505 #define FIB_MULTIPATH_HASH_FIELD_ALL_MASK \
506 (FIB_MULTIPATH_HASH_FIELD_OUTER_MASK | \
507 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
509 #define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK \
510 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
511 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
512 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
514 #ifdef CONFIG_IP_ROUTE_MULTIPATH
515 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
516 const struct sk_buff *skb, struct flow_keys *flkeys);
518 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
519 struct netlink_ext_ack *extack);
520 void fib_select_multipath(struct fib_result *res, int hash);
521 void fib_select_path(struct net *net, struct fib_result *res,
522 struct flowi4 *fl4, const struct sk_buff *skb);
524 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
525 struct fib_config *cfg, int nh_weight,
526 struct netlink_ext_ack *extack);
527 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
528 int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
529 struct nlattr *fc_encap, u16 fc_encap_type,
530 void *cfg, gfp_t gfp_flags,
531 struct netlink_ext_ack *extack);
532 void fib_nh_common_release(struct fib_nh_common *nhc);
534 /* Exported by fib_trie.c */
535 void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
536 void fib_trie_init(void);
537 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
538 bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
539 const struct flowi4 *flp);
541 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
543 #ifdef CONFIG_IP_ROUTE_CLASSID
544 struct fib_nh_common *nhc = res->nhc;
545 #ifdef CONFIG_IP_MULTIPLE_TABLES
548 if (nhc->nhc_family == AF_INET) {
551 nh = container_of(nhc, struct fib_nh, nh_common);
552 *itag = nh->nh_tclassid << 16;
557 #ifdef CONFIG_IP_MULTIPLE_TABLES
558 rtag = res->tclassid;
566 void fib_flush(struct net *net);
567 void free_fib_info(struct fib_info *fi);
569 static inline void fib_info_hold(struct fib_info *fi)
571 refcount_inc(&fi->fib_clntref);
574 static inline void fib_info_put(struct fib_info *fi)
576 if (refcount_dec_and_test(&fi->fib_clntref))
580 #ifdef CONFIG_PROC_FS
581 int __net_init fib_proc_init(struct net *net);
582 void __net_exit fib_proc_exit(struct net *net);
584 static inline int fib_proc_init(struct net *net)
588 static inline void fib_proc_exit(struct net *net)
593 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
595 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
596 struct fib_dump_filter *filter,
597 struct netlink_callback *cb);
599 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
600 u8 rt_family, unsigned char *flags, bool skip_oif);
601 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
602 int nh_weight, u8 rt_family, u32 nh_tclassid);
603 #endif /* _NET_FIB_H */