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/inet_dscp.h>
21 #include <net/inetpeer.h>
22 #include <linux/percpu.h>
23 #include <linux/notifier.h>
24 #include <linux/refcount.h>
38 struct in6_addr fc_gw6;
46 struct rtnexthop *fc_mp;
51 struct nl_info fc_nlinfo;
52 struct nlattr *fc_encap;
59 struct fib_nh_exception {
60 struct fib_nh_exception __rcu *fnhe_next;
66 unsigned long fnhe_expires;
67 struct rtable __rcu *fnhe_rth_input;
68 struct rtable __rcu *fnhe_rth_output;
69 unsigned long fnhe_stamp;
73 struct fnhe_hash_bucket {
74 struct fib_nh_exception __rcu *chain;
77 #define FNHE_HASH_SHIFT 11
78 #define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
79 #define FNHE_RECLAIM_DEPTH 5
81 struct fib_nh_common {
82 struct net_device *nhc_dev;
83 netdevice_tracker nhc_dev_tracker;
85 unsigned char nhc_scope;
88 unsigned char nhc_flags;
89 struct lwtunnel_state *nhc_lwtstate;
97 atomic_t nhc_upper_bound;
99 /* v4 specific, but allows fib6_nh with v4 routes */
100 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
101 struct rtable __rcu *nhc_rth_input;
102 struct fnhe_hash_bucket __rcu *nhc_exceptions;
106 struct fib_nh_common nh_common;
107 struct hlist_node nh_hash;
108 struct fib_info *nh_parent;
109 #ifdef CONFIG_IP_ROUTE_CLASSID
114 #define fib_nh_family nh_common.nhc_family
115 #define fib_nh_dev nh_common.nhc_dev
116 #define fib_nh_dev_tracker nh_common.nhc_dev_tracker
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.
135 struct hlist_node fib_hash;
136 struct hlist_node fib_lhash;
137 struct list_head nh_list;
139 refcount_t fib_treeref;
140 refcount_t fib_clntref;
141 unsigned int fib_flags;
142 unsigned char fib_dead;
143 unsigned char fib_protocol;
144 unsigned char fib_scope;
145 unsigned char fib_type;
149 struct dst_metrics *fib_metrics;
150 #define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
151 #define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
152 #define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
153 #define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
160 struct fib_nh fib_nh[] __counted_by(fib_nhs);
164 #ifdef CONFIG_IP_MULTIPLE_TABLES
171 unsigned char prefixlen;
172 unsigned char nh_sel;
176 struct fib_nh_common *nhc;
178 struct fib_table *table;
179 struct hlist_head *fa_head;
182 struct fib_result_nl {
183 __be32 fl_addr; /* To be looked up*/
185 unsigned char fl_tos;
186 unsigned char fl_scope;
187 unsigned char tb_id_in;
189 unsigned char tb_id; /* Results */
190 unsigned char prefixlen;
191 unsigned char nh_sel;
197 #ifdef CONFIG_IP_MULTIPLE_TABLES
198 #define FIB_TABLE_HASHSZ 256
200 #define FIB_TABLE_HASHSZ 2
203 __be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
204 unsigned char scope);
205 __be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
207 #define FIB_RES_NHC(res) ((res).nhc)
208 #define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
209 #define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
224 struct fib_entry_notifier_info {
225 struct fib_notifier_info info; /* must be first */
234 struct fib_nh_notifier_info {
235 struct fib_notifier_info info; /* must be first */
236 struct fib_nh *fib_nh;
239 int call_fib4_notifier(struct notifier_block *nb,
240 enum fib_event_type event_type,
241 struct fib_notifier_info *info);
242 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
243 struct fib_notifier_info *info);
245 int __net_init fib4_notifier_init(struct net *net);
246 void __net_exit fib4_notifier_exit(struct net *net);
248 void fib_info_notify_update(struct net *net, struct nl_info *info);
249 int fib_notify(struct net *net, struct notifier_block *nb,
250 struct netlink_ext_ack *extack);
253 struct hlist_node tb_hlist;
257 unsigned long *tb_data;
258 unsigned long __data[];
261 struct fib_dump_filter {
263 /* filter_set is an optimization that an entry is set */
266 bool dump_exceptions;
268 unsigned char protocol;
269 unsigned char rt_type;
271 struct net_device *dev;
274 int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
275 struct fib_result *res, int fib_flags);
276 int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
277 struct netlink_ext_ack *extack);
278 int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
279 struct netlink_ext_ack *extack);
280 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
281 struct netlink_callback *cb, struct fib_dump_filter *filter);
282 int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
283 struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
284 void fib_table_flush_external(struct fib_table *table);
285 void fib_free_table(struct fib_table *tb);
287 #ifndef CONFIG_IP_MULTIPLE_TABLES
289 #define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
290 #define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
292 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
294 struct hlist_node *tb_hlist;
295 struct hlist_head *ptr;
297 ptr = id == RT_TABLE_LOCAL ?
298 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
299 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
301 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
303 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
306 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
308 return fib_get_table(net, id);
311 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
312 struct fib_result *res, unsigned int flags)
314 struct fib_table *tb;
315 int err = -ENETUNREACH;
319 tb = fib_get_table(net, RT_TABLE_MAIN);
321 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
331 static inline bool fib4_has_custom_rules(const struct net *net)
336 static inline bool fib4_rule_default(const struct fib_rule *rule)
341 static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
342 struct netlink_ext_ack *extack)
347 static inline unsigned int fib4_rules_seq_read(struct net *net)
352 static inline bool fib4_rules_early_flow_dissect(struct net *net,
355 struct flow_keys *flkeys)
359 #else /* CONFIG_IP_MULTIPLE_TABLES */
360 int __net_init fib4_rules_init(struct net *net);
361 void __net_exit fib4_rules_exit(struct net *net);
363 struct fib_table *fib_new_table(struct net *net, u32 id);
364 struct fib_table *fib_get_table(struct net *net, u32 id);
366 int __fib_lookup(struct net *net, struct flowi4 *flp,
367 struct fib_result *res, unsigned int flags);
369 static inline int fib_lookup(struct net *net, struct flowi4 *flp,
370 struct fib_result *res, unsigned int flags)
372 struct fib_table *tb;
373 int err = -ENETUNREACH;
375 flags |= FIB_LOOKUP_NOREF;
376 if (net->ipv4.fib_has_custom_rules)
377 return __fib_lookup(net, flp, res, flags);
383 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
385 err = fib_table_lookup(tb, flp, res, flags);
390 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
392 err = fib_table_lookup(tb, flp, res, flags);
403 static inline bool fib4_has_custom_rules(const struct net *net)
405 return net->ipv4.fib_has_custom_rules;
408 bool fib4_rule_default(const struct fib_rule *rule);
409 int fib4_rules_dump(struct net *net, struct notifier_block *nb,
410 struct netlink_ext_ack *extack);
411 unsigned int fib4_rules_seq_read(struct net *net);
413 static inline bool fib4_rules_early_flow_dissect(struct net *net,
416 struct flow_keys *flkeys)
418 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
420 if (!net->ipv4.fib_rules_require_fldissect)
423 memset(flkeys, 0, sizeof(*flkeys));
424 __skb_flow_dissect(net, skb, &flow_keys_dissector,
425 flkeys, NULL, 0, 0, 0, flag);
427 fl4->fl4_sport = flkeys->ports.src;
428 fl4->fl4_dport = flkeys->ports.dst;
429 fl4->flowi4_proto = flkeys->basic.ip_proto;
434 #endif /* CONFIG_IP_MULTIPLE_TABLES */
436 /* Exported by fib_frontend.c */
437 extern const struct nla_policy rtm_ipv4_policy[];
438 void ip_fib_init(void);
439 int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
440 struct netlink_ext_ack *extack);
441 __be32 fib_compute_spec_dst(struct sk_buff *skb);
442 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
443 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
444 u8 tos, int oif, struct net_device *dev,
445 struct in_device *idev, u32 *itag);
446 #ifdef CONFIG_IP_ROUTE_CLASSID
447 static inline int fib_num_tclassid_users(struct net *net)
449 return atomic_read(&net->ipv4.fib_num_tclassid_users);
452 static inline int fib_num_tclassid_users(struct net *net)
457 int fib_unmerge(struct net *net);
459 static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
460 const struct net_device *dev)
462 if (nhc->nhc_dev == dev ||
463 l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
469 /* Exported by fib_semantics.c */
470 int ip_fib_check_default(__be32 gw, struct net_device *dev);
471 int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
472 int fib_sync_down_addr(struct net_device *dev, __be32 local);
473 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
474 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
475 void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
477 /* Fields used for sysctl_fib_multipath_hash_fields.
478 * Common to IPv4 and IPv6.
480 * Add new fields at the end. This is user API.
482 #define FIB_MULTIPATH_HASH_FIELD_SRC_IP BIT(0)
483 #define FIB_MULTIPATH_HASH_FIELD_DST_IP BIT(1)
484 #define FIB_MULTIPATH_HASH_FIELD_IP_PROTO BIT(2)
485 #define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL BIT(3)
486 #define FIB_MULTIPATH_HASH_FIELD_SRC_PORT BIT(4)
487 #define FIB_MULTIPATH_HASH_FIELD_DST_PORT BIT(5)
488 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP BIT(6)
489 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP BIT(7)
490 #define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO BIT(8)
491 #define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL BIT(9)
492 #define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT BIT(10)
493 #define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT BIT(11)
495 #define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK \
496 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
497 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
498 FIB_MULTIPATH_HASH_FIELD_IP_PROTO | \
499 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL | \
500 FIB_MULTIPATH_HASH_FIELD_SRC_PORT | \
501 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
503 #define FIB_MULTIPATH_HASH_FIELD_INNER_MASK \
504 (FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP | \
505 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP | \
506 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO | \
507 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL | \
508 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT | \
509 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
511 #define FIB_MULTIPATH_HASH_FIELD_ALL_MASK \
512 (FIB_MULTIPATH_HASH_FIELD_OUTER_MASK | \
513 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
515 #define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK \
516 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
517 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
518 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
520 #ifdef CONFIG_IP_ROUTE_MULTIPATH
521 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
522 const struct sk_buff *skb, struct flow_keys *flkeys);
524 int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
525 struct netlink_ext_ack *extack);
526 void fib_select_multipath(struct fib_result *res, int hash);
527 void fib_select_path(struct net *net, struct fib_result *res,
528 struct flowi4 *fl4, const struct sk_buff *skb);
530 int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
531 struct fib_config *cfg, int nh_weight,
532 struct netlink_ext_ack *extack);
533 void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
534 int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
535 struct nlattr *fc_encap, u16 fc_encap_type,
536 void *cfg, gfp_t gfp_flags,
537 struct netlink_ext_ack *extack);
538 void fib_nh_common_release(struct fib_nh_common *nhc);
540 /* Exported by fib_trie.c */
541 void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
542 void fib_trie_init(void);
543 struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
544 bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
545 const struct flowi4 *flp);
547 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
549 #ifdef CONFIG_IP_ROUTE_CLASSID
550 struct fib_nh_common *nhc = res->nhc;
551 #ifdef CONFIG_IP_MULTIPLE_TABLES
554 if (nhc->nhc_family == AF_INET) {
557 nh = container_of(nhc, struct fib_nh, nh_common);
558 *itag = nh->nh_tclassid << 16;
563 #ifdef CONFIG_IP_MULTIPLE_TABLES
564 rtag = res->tclassid;
572 void fib_flush(struct net *net);
573 void free_fib_info(struct fib_info *fi);
575 static inline void fib_info_hold(struct fib_info *fi)
577 refcount_inc(&fi->fib_clntref);
580 static inline void fib_info_put(struct fib_info *fi)
582 if (refcount_dec_and_test(&fi->fib_clntref))
586 #ifdef CONFIG_PROC_FS
587 int __net_init fib_proc_init(struct net *net);
588 void __net_exit fib_proc_exit(struct net *net);
590 static inline int fib_proc_init(struct net *net)
594 static inline void fib_proc_exit(struct net *net)
599 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
601 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
602 struct fib_dump_filter *filter,
603 struct netlink_callback *cb);
605 int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
606 u8 rt_family, unsigned char *flags, bool skip_oif);
607 int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
608 int nh_weight, u8 rt_family, u32 nh_tclassid);
609 #endif /* _NET_FIB_H */