ip_fib.h

  1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  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.
  6 *
  7 *		Definitions for the Forwarding Information Base.
  8 *
  9 * Authors:	A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
 10 */
 11
 12#ifndef _NET_IP_FIB_H
 13#define _NET_IP_FIB_H
 14
 15#include <net/flow.h>
 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>
 25#include <linux/ip.h>
 26#include <linux/in_route.h>
 27
 28struct fib_config {
 29	u8			fc_dst_len;
 30	dscp_t			fc_dscp;
 31	u8			fc_protocol;
 32	u8			fc_scope;
 33	u8			fc_type;
 34	u8			fc_gw_family;
 35	/* 2 bytes unused */
 36	u32			fc_table;
 37	__be32			fc_dst;
 38	union {
 39		__be32		fc_gw4;
 40		struct in6_addr	fc_gw6;
 41	};
 42	int			fc_oif;
 43	u32			fc_flags;
 44	u32			fc_priority;
 45	__be32			fc_prefsrc;
 46	u32			fc_nh_id;
 47	struct nlattr		*fc_mx;
 48	struct rtnexthop	*fc_mp;
 49	int			fc_mx_len;
 50	int			fc_mp_len;
 51	u32			fc_flow;
 52	u32			fc_nlflags;
 53	struct nl_info		fc_nlinfo;
 54	struct nlattr		*fc_encap;
 55	u16			fc_encap_type;
 56};
 57
 58struct fib_info;
 59struct rtable;
 60
 61struct fib_nh_exception {
 62	struct fib_nh_exception __rcu	*fnhe_next;
 63	int				fnhe_genid;
 64	__be32				fnhe_daddr;
 65	u32				fnhe_pmtu;
 66	bool				fnhe_mtu_locked;
 67	__be32				fnhe_gw;
 68	unsigned long			fnhe_expires;
 69	struct rtable __rcu		*fnhe_rth_input;
 70	struct rtable __rcu		*fnhe_rth_output;
 71	unsigned long			fnhe_stamp;
 72	struct rcu_head			rcu;
 73};
 74
 75struct fnhe_hash_bucket {
 76	struct fib_nh_exception __rcu	*chain;
 77};
 78
 79#define FNHE_HASH_SHIFT		11
 80#define FNHE_HASH_SIZE		(1 << FNHE_HASH_SHIFT)
 81#define FNHE_RECLAIM_DEPTH	5
 82
 83struct fib_nh_common {
 84	struct net_device	*nhc_dev;
 85	netdevice_tracker	nhc_dev_tracker;
 86	int			nhc_oif;
 87	unsigned char		nhc_scope;
 88	u8			nhc_family;
 89	u8			nhc_gw_family;
 90	unsigned char		nhc_flags;
 91	struct lwtunnel_state	*nhc_lwtstate;
 92
 93	union {
 94		__be32          ipv4;
 95		struct in6_addr ipv6;
 96	} nhc_gw;
 97
 98	int			nhc_weight;
 99	atomic_t		nhc_upper_bound;
100
101	/* v4 specific, but allows fib6_nh with v4 routes */
102	struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
103	struct rtable __rcu     *nhc_rth_input;
104	struct fnhe_hash_bucket	__rcu *nhc_exceptions;
105};
106
107struct fib_nh {
108	struct fib_nh_common	nh_common;
109	struct hlist_node	nh_hash;
110	struct fib_info		*nh_parent;
111#ifdef CONFIG_IP_ROUTE_CLASSID
112	__u32			nh_tclassid;
113#endif
114	__be32			nh_saddr;
115	int			nh_saddr_genid;
116#define fib_nh_family		nh_common.nhc_family
117#define fib_nh_dev		nh_common.nhc_dev
118#define fib_nh_dev_tracker	nh_common.nhc_dev_tracker
119#define fib_nh_oif		nh_common.nhc_oif
120#define fib_nh_flags		nh_common.nhc_flags
121#define fib_nh_lws		nh_common.nhc_lwtstate
122#define fib_nh_scope		nh_common.nhc_scope
123#define fib_nh_gw_family	nh_common.nhc_gw_family
124#define fib_nh_gw4		nh_common.nhc_gw.ipv4
125#define fib_nh_gw6		nh_common.nhc_gw.ipv6
126#define fib_nh_weight		nh_common.nhc_weight
127#define fib_nh_upper_bound	nh_common.nhc_upper_bound
128};
129
130/*
131 * This structure contains data shared by many of routes.
132 */
133
134struct nexthop;
135
136struct fib_info {
137	struct hlist_node	fib_hash;
138	struct hlist_node	fib_lhash;
139	struct list_head	nh_list;
140	struct net		*fib_net;
141	refcount_t		fib_treeref;
142	refcount_t		fib_clntref;
143	unsigned int		fib_flags;
144	unsigned char		fib_dead;
145	unsigned char		fib_protocol;
146	unsigned char		fib_scope;
147	unsigned char		fib_type;
148	__be32			fib_prefsrc;
149	u32			fib_tb_id;
150	u32			fib_priority;
151	struct dst_metrics	*fib_metrics;
152#define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
153#define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
154#define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
155#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
156	int			fib_nhs;
157	bool			fib_nh_is_v6;
158	bool			nh_updated;
159	bool			pfsrc_removed;
160	struct nexthop		*nh;
161	struct rcu_head		rcu;
162	struct fib_nh		fib_nh[] __counted_by(fib_nhs);
163};
164
165int __net_init fib4_semantics_init(struct net *net);
166void __net_exit fib4_semantics_exit(struct net *net);
167
168#ifdef CONFIG_IP_MULTIPLE_TABLES
169struct fib_rule;
170#endif
171
172struct fib_table;
173struct fib_result {
174	__be32			prefix;
175	unsigned char		prefixlen;
176	unsigned char		nh_sel;
177	unsigned char		type;
178	unsigned char		scope;
179	u32			tclassid;
180	dscp_t			dscp;
181	struct fib_nh_common	*nhc;
182	struct fib_info		*fi;
183	struct fib_table	*table;
184	struct hlist_head	*fa_head;
185};
186
187struct fib_result_nl {
188	__be32		fl_addr;   /* To be looked up*/
189	u32		fl_mark;
190	unsigned char	fl_tos;
191	unsigned char   fl_scope;
192	unsigned char   tb_id_in;
193
194	unsigned char   tb_id;      /* Results */
195	unsigned char	prefixlen;
196	unsigned char	nh_sel;
197	unsigned char	type;
198	unsigned char	scope;
199	int             err;
200};
201
202#ifdef CONFIG_IP_MULTIPLE_TABLES
203#define FIB_TABLE_HASHSZ 256
204#else
205#define FIB_TABLE_HASHSZ 2
206#endif
207
208__be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
209				 unsigned char scope);
210__be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
211
212#define FIB_RES_NHC(res)		((res).nhc)
213#define FIB_RES_DEV(res)	(FIB_RES_NHC(res)->nhc_dev)
214#define FIB_RES_OIF(res)	(FIB_RES_NHC(res)->nhc_oif)
215
216struct fib_rt_info {
217	struct fib_info		*fi;
218	u32			tb_id;
219	__be32			dst;
220	int			dst_len;
221	dscp_t			dscp;
222	u8			type;
223	u8			offload:1,
224				trap:1,
225				offload_failed:1,
226				unused:5;
227};
228
229struct fib_entry_notifier_info {
230	struct fib_notifier_info info; /* must be first */
231	u32 dst;
232	int dst_len;
233	struct fib_info *fi;
234	dscp_t dscp;
235	u8 type;
236	u32 tb_id;
237};
238
239struct fib_nh_notifier_info {
240	struct fib_notifier_info info; /* must be first */
241	struct fib_nh *fib_nh;
242};
243
244int call_fib4_notifier(struct notifier_block *nb,
245		       enum fib_event_type event_type,
246		       struct fib_notifier_info *info);
247int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
248			struct fib_notifier_info *info);
249
250int __net_init fib4_notifier_init(struct net *net);
251void __net_exit fib4_notifier_exit(struct net *net);
252
253void fib_info_notify_update(struct net *net, struct nl_info *info);
254int fib_notify(struct net *net, struct notifier_block *nb,
255	       struct netlink_ext_ack *extack);
256
257struct fib_table {
258	struct hlist_node	tb_hlist;
259	u32			tb_id;
260	int			tb_num_default;
261	struct rcu_head		rcu;
262	unsigned long 		*tb_data;
263	unsigned long		__data[];
264};
265
266struct fib_dump_filter {
267	u32			table_id;
268	/* filter_set is an optimization that an entry is set */
269	bool			filter_set;
270	bool			dump_routes;
271	bool			dump_exceptions;
272	bool			rtnl_held;
273	unsigned char		protocol;
274	unsigned char		rt_type;
275	unsigned int		flags;
276	struct net_device	*dev;
277};
278
279int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
280		     struct fib_result *res, int fib_flags);
281int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
282		     struct netlink_ext_ack *extack);
283int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
284		     struct netlink_ext_ack *extack);
285int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
286		   struct netlink_callback *cb, struct fib_dump_filter *filter);
287int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
288struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
289void fib_table_flush_external(struct fib_table *table);
290void fib_free_table(struct fib_table *tb);
291
292#ifndef CONFIG_IP_MULTIPLE_TABLES
293
294#define TABLE_LOCAL_INDEX	(RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
295#define TABLE_MAIN_INDEX	(RT_TABLE_MAIN  & (FIB_TABLE_HASHSZ - 1))
296
297static inline struct fib_table *fib_get_table(struct net *net, u32 id)
298{
299	struct hlist_node *tb_hlist;
300	struct hlist_head *ptr;
301
302	ptr = id == RT_TABLE_LOCAL ?
303		&net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
304		&net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
305
306	tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
307
308	return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
309}
310
311static inline struct fib_table *fib_new_table(struct net *net, u32 id)
312{
313	return fib_get_table(net, id);
314}
315
316static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
317			     struct fib_result *res, unsigned int flags)
318{
319	struct fib_table *tb;
320	int err = -ENETUNREACH;
321
322	rcu_read_lock();
323
324	tb = fib_get_table(net, RT_TABLE_MAIN);
325	if (tb)
326		err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
327
328	if (err == -EAGAIN)
329		err = -ENETUNREACH;
330
331	rcu_read_unlock();
332
333	return err;
334}
335
336static inline bool fib4_has_custom_rules(const struct net *net)
337{
338	return false;
339}
340
341static inline bool fib4_rule_default(const struct fib_rule *rule)
342{
343	return true;
344}
345
346static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
347				  struct netlink_ext_ack *extack)
348{
349	return 0;
350}
351
352static inline unsigned int fib4_rules_seq_read(const struct net *net)
353{
354	return 0;
355}
356
357static inline bool fib4_rules_early_flow_dissect(struct net *net,
358						 struct sk_buff *skb,
359						 struct flowi4 *fl4,
360						 struct flow_keys *flkeys)
361{
362	return false;
363}
364#else /* CONFIG_IP_MULTIPLE_TABLES */
365int __net_init fib4_rules_init(struct net *net);
366void __net_exit fib4_rules_exit(struct net *net);
367
368struct fib_table *fib_new_table(struct net *net, u32 id);
369struct fib_table *fib_get_table(struct net *net, u32 id);
370
371int __fib_lookup(struct net *net, struct flowi4 *flp,
372		 struct fib_result *res, unsigned int flags);
373
374static inline int fib_lookup(struct net *net, struct flowi4 *flp,
375			     struct fib_result *res, unsigned int flags)
376{
377	struct fib_table *tb;
378	int err = -ENETUNREACH;
379
380	flags |= FIB_LOOKUP_NOREF;
381	if (net->ipv4.fib_has_custom_rules)
382		return __fib_lookup(net, flp, res, flags);
383
384	rcu_read_lock();
385
386	res->tclassid = 0;
387
388	tb = rcu_dereference_rtnl(net->ipv4.fib_main);
389	if (tb)
390		err = fib_table_lookup(tb, flp, res, flags);
391
392	if (!err)
393		goto out;
394
395	tb = rcu_dereference_rtnl(net->ipv4.fib_default);
396	if (tb)
397		err = fib_table_lookup(tb, flp, res, flags);
398
399out:
400	if (err == -EAGAIN)
401		err = -ENETUNREACH;
402
403	rcu_read_unlock();
404
405	return err;
406}
407
408static inline bool fib4_has_custom_rules(const struct net *net)
409{
410	return net->ipv4.fib_has_custom_rules;
411}
412
413bool fib4_rule_default(const struct fib_rule *rule);
414int fib4_rules_dump(struct net *net, struct notifier_block *nb,
415		    struct netlink_ext_ack *extack);
416unsigned int fib4_rules_seq_read(const struct net *net);
417
418static inline bool fib4_rules_early_flow_dissect(struct net *net,
419						 struct sk_buff *skb,
420						 struct flowi4 *fl4,
421						 struct flow_keys *flkeys)
422{
423	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
424
425	if (!net->ipv4.fib_rules_require_fldissect)
426		return false;
427
428	memset(flkeys, 0, sizeof(*flkeys));
429	__skb_flow_dissect(net, skb, &flow_keys_dissector,
430			   flkeys, NULL, 0, 0, 0, flag);
431
432	fl4->fl4_sport = flkeys->ports.src;
433	fl4->fl4_dport = flkeys->ports.dst;
434	fl4->flowi4_proto = flkeys->basic.ip_proto;
435
436	return true;
437}
438
439#endif /* CONFIG_IP_MULTIPLE_TABLES */
440
441static inline bool fib_dscp_masked_match(dscp_t dscp, const struct flowi4 *fl4)
442{
443	return dscp == (fl4->flowi4_dscp & INET_DSCP_LEGACY_TOS_MASK);
444}
445
446/* Exported by fib_frontend.c */
447extern const struct nla_policy rtm_ipv4_policy[];
448void ip_fib_init(void);
449int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
450		    struct netlink_ext_ack *extack);
451__be32 fib_compute_spec_dst(struct sk_buff *skb);
452bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
453int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
454			dscp_t dscp, int oif, struct net_device *dev,
455			struct in_device *idev, u32 *itag);
456
457static inline enum skb_drop_reason
458fib_validate_source_reason(struct sk_buff *skb, __be32 src, __be32 dst,
459			   dscp_t dscp, int oif, struct net_device *dev,
460			   struct in_device *idev, u32 *itag)
461{
462	int err = fib_validate_source(skb, src, dst, dscp, oif, dev, idev,
463				      itag);
464	if (err < 0)
465		return -err;
466	return SKB_NOT_DROPPED_YET;
467}
468
469#ifdef CONFIG_IP_ROUTE_CLASSID
470static inline int fib_num_tclassid_users(struct net *net)
471{
472	return atomic_read(&net->ipv4.fib_num_tclassid_users);
473}
474#else
475static inline int fib_num_tclassid_users(struct net *net)
476{
477	return 0;
478}
479#endif
480int fib_unmerge(struct net *net);
481
482static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
483const struct net_device *dev)
484{
485	if (nhc->nhc_dev == dev ||
486	    l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
487		return true;
488
489	return false;
490}
491
492/* Exported by fib_semantics.c */
493int ip_fib_check_default(__be32 gw, struct net_device *dev);
494int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
495int fib_sync_down_addr(struct net_device *dev, __be32 local);
496int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
497void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
498void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
499
500/* Fields used for sysctl_fib_multipath_hash_fields.
501 * Common to IPv4 and IPv6.
502 *
503 * Add new fields at the end. This is user API.
504 */
505#define FIB_MULTIPATH_HASH_FIELD_SRC_IP			BIT(0)
506#define FIB_MULTIPATH_HASH_FIELD_DST_IP			BIT(1)
507#define FIB_MULTIPATH_HASH_FIELD_IP_PROTO		BIT(2)
508#define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL		BIT(3)
509#define FIB_MULTIPATH_HASH_FIELD_SRC_PORT		BIT(4)
510#define FIB_MULTIPATH_HASH_FIELD_DST_PORT		BIT(5)
511#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP		BIT(6)
512#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP		BIT(7)
513#define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO		BIT(8)
514#define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL	BIT(9)
515#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT		BIT(10)
516#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT		BIT(11)
517
518#define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK		\
519	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
520	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
521	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO |		\
522	 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL |		\
523	 FIB_MULTIPATH_HASH_FIELD_SRC_PORT |		\
524	 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
525
526#define FIB_MULTIPATH_HASH_FIELD_INNER_MASK		\
527	(FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP |	\
528	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP |	\
529	 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO |	\
530	 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL |	\
531	 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT |	\
532	 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
533
534#define FIB_MULTIPATH_HASH_FIELD_ALL_MASK		\
535	(FIB_MULTIPATH_HASH_FIELD_OUTER_MASK |		\
536	 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
537
538#define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK		\
539	(FIB_MULTIPATH_HASH_FIELD_SRC_IP |		\
540	 FIB_MULTIPATH_HASH_FIELD_DST_IP |		\
541	 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
542
543#ifdef CONFIG_IP_ROUTE_MULTIPATH
544int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
545		       const struct sk_buff *skb, struct flow_keys *flkeys);
546
547static void
548fib_multipath_hash_construct_key(siphash_key_t *key, u32 mp_seed)
549{
550	u64 mp_seed_64 = mp_seed;
551
552	key->key[0] = (mp_seed_64 << 32) | mp_seed_64;
553	key->key[1] = key->key[0];
554}
555
556static inline u32 fib_multipath_hash_from_keys(const struct net *net,
557					       struct flow_keys *keys)
558{
559	siphash_aligned_key_t hash_key;
560	u32 mp_seed;
561
562	mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed.mp_seed);
563	fib_multipath_hash_construct_key(&hash_key, mp_seed);
564
565	return flow_hash_from_keys_seed(keys, &hash_key);
566}
567#else
568static inline u32 fib_multipath_hash_from_keys(const struct net *net,
569					       struct flow_keys *keys)
570{
571	return flow_hash_from_keys(keys);
572}
573#endif
574
575int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
576		 struct netlink_ext_ack *extack);
577void fib_select_multipath(struct fib_result *res, int hash,
578			  const struct flowi4 *fl4);
579void fib_select_path(struct net *net, struct fib_result *res,
580		     struct flowi4 *fl4, const struct sk_buff *skb);
581
582int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
583		struct fib_config *cfg, int nh_weight,
584		struct netlink_ext_ack *extack);
585void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
586int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
587		       struct nlattr *fc_encap, u16 fc_encap_type,
588		       void *cfg, gfp_t gfp_flags,
589		       struct netlink_ext_ack *extack);
590void fib_nh_common_release(struct fib_nh_common *nhc);
591
592/* Exported by fib_trie.c */
593void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
594void fib_trie_init(void);
595struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
596bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
597			 const struct flowi4 *flp);
598
599static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
600{
601#ifdef CONFIG_IP_ROUTE_CLASSID
602	struct fib_nh_common *nhc = res->nhc;
603#ifdef CONFIG_IP_MULTIPLE_TABLES
604	u32 rtag;
605#endif
606	if (nhc->nhc_family == AF_INET) {
607		struct fib_nh *nh;
608
609		nh = container_of(nhc, struct fib_nh, nh_common);
610		*itag = nh->nh_tclassid << 16;
611	} else {
612		*itag = 0;
613	}
614
615#ifdef CONFIG_IP_MULTIPLE_TABLES
616	rtag = res->tclassid;
617	if (*itag == 0)
618		*itag = (rtag<<16);
619	*itag |= (rtag>>16);
620#endif
621#endif
622}
623
624void fib_flush(struct net *net);
625void free_fib_info(struct fib_info *fi);
626
627static inline void fib_info_hold(struct fib_info *fi)
628{
629	refcount_inc(&fi->fib_clntref);
630}
631
632static inline void fib_info_put(struct fib_info *fi)
633{
634	if (refcount_dec_and_test(&fi->fib_clntref))
635		free_fib_info(fi);
636}
637
638#ifdef CONFIG_PROC_FS
639int __net_init fib_proc_init(struct net *net);
640void __net_exit fib_proc_exit(struct net *net);
641#else
642static inline int fib_proc_init(struct net *net)
643{
644	return 0;
645}
646static inline void fib_proc_exit(struct net *net)
647{
648}
649#endif
650
651u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
652
653int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
654			  struct fib_dump_filter *filter,
655			  struct netlink_callback *cb);
656
657int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
658		     u8 rt_family, unsigned char *flags, bool skip_oif);
659int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
660		    int nh_weight, u8 rt_family, u32 nh_tclassid);
661#endif  /* _NET_FIB_H */