xref: /linux/include/net/ip6_fib.h (revision 79ac11393328fb1717d17c12e3c0eef0e9fa0647)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  */
8 
9 #ifndef _IP6_FIB_H
10 #define _IP6_FIB_H
11 
12 #include <linux/ipv6_route.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/spinlock.h>
15 #include <linux/notifier.h>
16 #include <net/dst.h>
17 #include <net/flow.h>
18 #include <net/ip_fib.h>
19 #include <net/netlink.h>
20 #include <net/inetpeer.h>
21 #include <net/fib_notifier.h>
22 #include <linux/indirect_call_wrapper.h>
23 #include <uapi/linux/bpf.h>
24 
25 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
26 #define FIB6_TABLE_HASHSZ 256
27 #else
28 #define FIB6_TABLE_HASHSZ 1
29 #endif
30 
31 #define RT6_DEBUG 2
32 
33 #if RT6_DEBUG >= 3
34 #define RT6_TRACE(x...) pr_debug(x)
35 #else
36 #define RT6_TRACE(x...) do { ; } while (0)
37 #endif
38 
39 struct rt6_info;
40 struct fib6_info;
41 
42 struct fib6_config {
43 	u32		fc_table;
44 	u32		fc_metric;
45 	int		fc_dst_len;
46 	int		fc_src_len;
47 	int		fc_ifindex;
48 	u32		fc_flags;
49 	u32		fc_protocol;
50 	u16		fc_type;        /* only 8 bits are used */
51 	u16		fc_delete_all_nh : 1,
52 			fc_ignore_dev_down:1,
53 			__unused : 14;
54 	u32		fc_nh_id;
55 
56 	struct in6_addr	fc_dst;
57 	struct in6_addr	fc_src;
58 	struct in6_addr	fc_prefsrc;
59 	struct in6_addr	fc_gateway;
60 
61 	unsigned long	fc_expires;
62 	struct nlattr	*fc_mx;
63 	int		fc_mx_len;
64 	int		fc_mp_len;
65 	struct nlattr	*fc_mp;
66 
67 	struct nl_info	fc_nlinfo;
68 	struct nlattr	*fc_encap;
69 	u16		fc_encap_type;
70 	bool		fc_is_fdb;
71 };
72 
73 struct fib6_node {
74 	struct fib6_node __rcu	*parent;
75 	struct fib6_node __rcu	*left;
76 	struct fib6_node __rcu	*right;
77 #ifdef CONFIG_IPV6_SUBTREES
78 	struct fib6_node __rcu	*subtree;
79 #endif
80 	struct fib6_info __rcu	*leaf;
81 
82 	__u16			fn_bit;		/* bit key */
83 	__u16			fn_flags;
84 	int			fn_sernum;
85 	struct fib6_info __rcu	*rr_ptr;
86 	struct rcu_head		rcu;
87 };
88 
89 struct fib6_gc_args {
90 	int			timeout;
91 	int			more;
92 };
93 
94 #ifndef CONFIG_IPV6_SUBTREES
95 #define FIB6_SUBTREE(fn)	NULL
96 
97 static inline bool fib6_routes_require_src(const struct net *net)
98 {
99 	return false;
100 }
101 
102 static inline void fib6_routes_require_src_inc(struct net *net) {}
103 static inline void fib6_routes_require_src_dec(struct net *net) {}
104 
105 #else
106 
107 static inline bool fib6_routes_require_src(const struct net *net)
108 {
109 	return net->ipv6.fib6_routes_require_src > 0;
110 }
111 
112 static inline void fib6_routes_require_src_inc(struct net *net)
113 {
114 	net->ipv6.fib6_routes_require_src++;
115 }
116 
117 static inline void fib6_routes_require_src_dec(struct net *net)
118 {
119 	net->ipv6.fib6_routes_require_src--;
120 }
121 
122 #define FIB6_SUBTREE(fn)	(rcu_dereference_protected((fn)->subtree, 1))
123 #endif
124 
125 /*
126  *	routing information
127  *
128  */
129 
130 struct rt6key {
131 	struct in6_addr	addr;
132 	int		plen;
133 };
134 
135 struct fib6_table;
136 
137 struct rt6_exception_bucket {
138 	struct hlist_head	chain;
139 	int			depth;
140 };
141 
142 struct rt6_exception {
143 	struct hlist_node	hlist;
144 	struct rt6_info		*rt6i;
145 	unsigned long		stamp;
146 	struct rcu_head		rcu;
147 };
148 
149 #define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
150 #define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
151 #define FIB6_MAX_DEPTH 5
152 
153 struct fib6_nh {
154 	struct fib_nh_common	nh_common;
155 
156 #ifdef CONFIG_IPV6_ROUTER_PREF
157 	unsigned long		last_probe;
158 #endif
159 
160 	struct rt6_info * __percpu *rt6i_pcpu;
161 	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
162 };
163 
164 struct fib6_info {
165 	struct fib6_table		*fib6_table;
166 	struct fib6_info __rcu		*fib6_next;
167 	struct fib6_node __rcu		*fib6_node;
168 
169 	/* Multipath routes:
170 	 * siblings is a list of fib6_info that have the same metric/weight,
171 	 * destination, but not the same gateway. nsiblings is just a cache
172 	 * to speed up lookup.
173 	 */
174 	union {
175 		struct list_head	fib6_siblings;
176 		struct list_head	nh_list;
177 	};
178 	unsigned int			fib6_nsiblings;
179 
180 	refcount_t			fib6_ref;
181 	unsigned long			expires;
182 
183 	struct hlist_node		gc_link;
184 
185 	struct dst_metrics		*fib6_metrics;
186 #define fib6_pmtu		fib6_metrics->metrics[RTAX_MTU-1]
187 
188 	struct rt6key			fib6_dst;
189 	u32				fib6_flags;
190 	struct rt6key			fib6_src;
191 	struct rt6key			fib6_prefsrc;
192 
193 	u32				fib6_metric;
194 	u8				fib6_protocol;
195 	u8				fib6_type;
196 
197 	u8				offload;
198 	u8				trap;
199 	u8				offload_failed;
200 
201 	u8				should_flush:1,
202 					dst_nocount:1,
203 					dst_nopolicy:1,
204 					fib6_destroying:1,
205 					unused:4;
206 
207 	struct rcu_head			rcu;
208 	struct nexthop			*nh;
209 	struct fib6_nh			fib6_nh[];
210 };
211 
212 struct rt6_info {
213 	struct dst_entry		dst;
214 	struct fib6_info __rcu		*from;
215 	int				sernum;
216 
217 	struct rt6key			rt6i_dst;
218 	struct rt6key			rt6i_src;
219 	struct in6_addr			rt6i_gateway;
220 	struct inet6_dev		*rt6i_idev;
221 	u32				rt6i_flags;
222 
223 	/* more non-fragment space at head required */
224 	unsigned short			rt6i_nfheader_len;
225 };
226 
227 struct fib6_result {
228 	struct fib6_nh		*nh;
229 	struct fib6_info	*f6i;
230 	u32			fib6_flags;
231 	u8			fib6_type;
232 	struct rt6_info		*rt6;
233 };
234 
235 #define for_each_fib6_node_rt_rcu(fn)					\
236 	for (rt = rcu_dereference((fn)->leaf); rt;			\
237 	     rt = rcu_dereference(rt->fib6_next))
238 
239 #define for_each_fib6_walker_rt(w)					\
240 	for (rt = (w)->leaf; rt;					\
241 	     rt = rcu_dereference_protected(rt->fib6_next, 1))
242 
243 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
244 {
245 	return ((struct rt6_info *)dst)->rt6i_idev;
246 }
247 
248 static inline bool fib6_requires_src(const struct fib6_info *rt)
249 {
250 	return rt->fib6_src.plen > 0;
251 }
252 
253 static inline bool fib6_check_expired(const struct fib6_info *f6i)
254 {
255 	if (f6i->fib6_flags & RTF_EXPIRES)
256 		return time_after(jiffies, f6i->expires);
257 	return false;
258 }
259 
260 static inline bool fib6_has_expires(const struct fib6_info *f6i)
261 {
262 	return f6i->fib6_flags & RTF_EXPIRES;
263 }
264 
265 /* Function to safely get fn->fn_sernum for passed in rt
266  * and store result in passed in cookie.
267  * Return true if we can get cookie safely
268  * Return false if not
269  */
270 static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
271 					u32 *cookie)
272 {
273 	struct fib6_node *fn;
274 	bool status = false;
275 
276 	fn = rcu_dereference(f6i->fib6_node);
277 
278 	if (fn) {
279 		*cookie = READ_ONCE(fn->fn_sernum);
280 		/* pairs with smp_wmb() in __fib6_update_sernum_upto_root() */
281 		smp_rmb();
282 		status = true;
283 	}
284 
285 	return status;
286 }
287 
288 static inline u32 rt6_get_cookie(const struct rt6_info *rt)
289 {
290 	struct fib6_info *from;
291 	u32 cookie = 0;
292 
293 	if (rt->sernum)
294 		return rt->sernum;
295 
296 	rcu_read_lock();
297 
298 	from = rcu_dereference(rt->from);
299 	if (from)
300 		fib6_get_cookie_safe(from, &cookie);
301 
302 	rcu_read_unlock();
303 
304 	return cookie;
305 }
306 
307 static inline void ip6_rt_put(struct rt6_info *rt)
308 {
309 	/* dst_release() accepts a NULL parameter.
310 	 * We rely on dst being first structure in struct rt6_info
311 	 */
312 	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
313 	dst_release(&rt->dst);
314 }
315 
316 struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
317 void fib6_info_destroy_rcu(struct rcu_head *head);
318 
319 static inline void fib6_info_hold(struct fib6_info *f6i)
320 {
321 	refcount_inc(&f6i->fib6_ref);
322 }
323 
324 static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
325 {
326 	return refcount_inc_not_zero(&f6i->fib6_ref);
327 }
328 
329 static inline void fib6_info_release(struct fib6_info *f6i)
330 {
331 	if (f6i && refcount_dec_and_test(&f6i->fib6_ref)) {
332 		DEBUG_NET_WARN_ON_ONCE(!hlist_unhashed(&f6i->gc_link));
333 		call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
334 	}
335 }
336 
337 enum fib6_walk_state {
338 #ifdef CONFIG_IPV6_SUBTREES
339 	FWS_S,
340 #endif
341 	FWS_L,
342 	FWS_R,
343 	FWS_C,
344 	FWS_U
345 };
346 
347 struct fib6_walker {
348 	struct list_head lh;
349 	struct fib6_node *root, *node;
350 	struct fib6_info *leaf;
351 	enum fib6_walk_state state;
352 	unsigned int skip;
353 	unsigned int count;
354 	unsigned int skip_in_node;
355 	int (*func)(struct fib6_walker *);
356 	void *args;
357 };
358 
359 struct rt6_statistics {
360 	__u32		fib_nodes;		/* all fib6 nodes */
361 	__u32		fib_route_nodes;	/* intermediate nodes */
362 	__u32		fib_rt_entries;		/* rt entries in fib table */
363 	__u32		fib_rt_cache;		/* cached rt entries in exception table */
364 	__u32		fib_discarded_routes;	/* total number of routes delete */
365 
366 	/* The following stat is not protected by any lock */
367 	atomic_t	fib_rt_alloc;		/* total number of routes alloced */
368 };
369 
370 #define RTN_TL_ROOT	0x0001
371 #define RTN_ROOT	0x0002		/* tree root node		*/
372 #define RTN_RTINFO	0x0004		/* node with valid routing info	*/
373 
374 /*
375  *	priority levels (or metrics)
376  *
377  */
378 
379 
380 struct fib6_table {
381 	struct hlist_node	tb6_hlist;
382 	u32			tb6_id;
383 	spinlock_t		tb6_lock;
384 	struct fib6_node	tb6_root;
385 	struct inet_peer_base	tb6_peers;
386 	unsigned int		flags;
387 	unsigned int		fib_seq;
388 	struct hlist_head       tb6_gc_hlist;	/* GC candidates */
389 #define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)
390 };
391 
392 #define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
393 #define RT6_TABLE_MAIN		RT_TABLE_MAIN
394 #define RT6_TABLE_DFLT		RT6_TABLE_MAIN
395 #define RT6_TABLE_INFO		RT6_TABLE_MAIN
396 #define RT6_TABLE_PREFIX	RT6_TABLE_MAIN
397 
398 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
399 #define FIB6_TABLE_MIN		1
400 #define FIB6_TABLE_MAX		RT_TABLE_MAX
401 #define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
402 #else
403 #define FIB6_TABLE_MIN		RT_TABLE_MAIN
404 #define FIB6_TABLE_MAX		FIB6_TABLE_MIN
405 #define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
406 #endif
407 
408 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
409 					 struct fib6_table *,
410 					 struct flowi6 *,
411 					 const struct sk_buff *, int);
412 
413 struct fib6_entry_notifier_info {
414 	struct fib_notifier_info info; /* must be first */
415 	struct fib6_info *rt;
416 	unsigned int nsiblings;
417 };
418 
419 /*
420  *	exported functions
421  */
422 
423 struct fib6_table *fib6_get_table(struct net *net, u32 id);
424 struct fib6_table *fib6_new_table(struct net *net, u32 id);
425 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
426 				   const struct sk_buff *skb,
427 				   int flags, pol_lookup_t lookup);
428 
429 /* called with rcu lock held; can return error pointer
430  * caller needs to select path
431  */
432 int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
433 		struct fib6_result *res, int flags);
434 
435 /* called with rcu lock held; caller needs to select path */
436 int fib6_table_lookup(struct net *net, struct fib6_table *table,
437 		      int oif, struct flowi6 *fl6, struct fib6_result *res,
438 		      int strict);
439 
440 void fib6_select_path(const struct net *net, struct fib6_result *res,
441 		      struct flowi6 *fl6, int oif, bool have_oif_match,
442 		      const struct sk_buff *skb, int strict);
443 struct fib6_node *fib6_node_lookup(struct fib6_node *root,
444 				   const struct in6_addr *daddr,
445 				   const struct in6_addr *saddr);
446 
447 struct fib6_node *fib6_locate(struct fib6_node *root,
448 			      const struct in6_addr *daddr, int dst_len,
449 			      const struct in6_addr *saddr, int src_len,
450 			      bool exact_match);
451 
452 void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
453 		    void *arg);
454 void fib6_clean_all_skip_notify(struct net *net,
455 				int (*func)(struct fib6_info *, void *arg),
456 				void *arg);
457 
458 int fib6_add(struct fib6_node *root, struct fib6_info *rt,
459 	     struct nl_info *info, struct netlink_ext_ack *extack);
460 int fib6_del(struct fib6_info *rt, struct nl_info *info);
461 
462 static inline
463 void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
464 {
465 	const struct fib6_info *from;
466 
467 	rcu_read_lock();
468 
469 	from = rcu_dereference(rt->from);
470 	if (from)
471 		*addr = from->fib6_prefsrc.addr;
472 	else
473 		*addr = in6addr_any;
474 
475 	rcu_read_unlock();
476 }
477 
478 int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
479 		 struct fib6_config *cfg, gfp_t gfp_flags,
480 		 struct netlink_ext_ack *extack);
481 void fib6_nh_release(struct fib6_nh *fib6_nh);
482 void fib6_nh_release_dsts(struct fib6_nh *fib6_nh);
483 
484 int call_fib6_entry_notifiers(struct net *net,
485 			      enum fib_event_type event_type,
486 			      struct fib6_info *rt,
487 			      struct netlink_ext_ack *extack);
488 int call_fib6_multipath_entry_notifiers(struct net *net,
489 					enum fib_event_type event_type,
490 					struct fib6_info *rt,
491 					unsigned int nsiblings,
492 					struct netlink_ext_ack *extack);
493 int call_fib6_entry_notifiers_replace(struct net *net, struct fib6_info *rt);
494 void fib6_rt_update(struct net *net, struct fib6_info *rt,
495 		    struct nl_info *info);
496 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
497 		     unsigned int flags);
498 
499 void fib6_run_gc(unsigned long expires, struct net *net, bool force);
500 
501 void fib6_gc_cleanup(void);
502 
503 int fib6_init(void);
504 
505 /* fib6_info must be locked by the caller, and fib6_info->fib6_table can be
506  * NULL.
507  */
508 static inline void fib6_set_expires_locked(struct fib6_info *f6i,
509 					   unsigned long expires)
510 {
511 	struct fib6_table *tb6;
512 
513 	tb6 = f6i->fib6_table;
514 	f6i->expires = expires;
515 	if (tb6 && !fib6_has_expires(f6i))
516 		hlist_add_head(&f6i->gc_link, &tb6->tb6_gc_hlist);
517 	f6i->fib6_flags |= RTF_EXPIRES;
518 }
519 
520 /* fib6_info must be locked by the caller, and fib6_info->fib6_table can be
521  * NULL.  If fib6_table is NULL, the fib6_info will no be inserted into the
522  * list of GC candidates until it is inserted into a table.
523  */
524 static inline void fib6_set_expires(struct fib6_info *f6i,
525 				    unsigned long expires)
526 {
527 	spin_lock_bh(&f6i->fib6_table->tb6_lock);
528 	fib6_set_expires_locked(f6i, expires);
529 	spin_unlock_bh(&f6i->fib6_table->tb6_lock);
530 }
531 
532 static inline void fib6_clean_expires_locked(struct fib6_info *f6i)
533 {
534 	if (fib6_has_expires(f6i))
535 		hlist_del_init(&f6i->gc_link);
536 	f6i->fib6_flags &= ~RTF_EXPIRES;
537 	f6i->expires = 0;
538 }
539 
540 static inline void fib6_clean_expires(struct fib6_info *f6i)
541 {
542 	spin_lock_bh(&f6i->fib6_table->tb6_lock);
543 	fib6_clean_expires_locked(f6i);
544 	spin_unlock_bh(&f6i->fib6_table->tb6_lock);
545 }
546 
547 struct ipv6_route_iter {
548 	struct seq_net_private p;
549 	struct fib6_walker w;
550 	loff_t skip;
551 	struct fib6_table *tbl;
552 	int sernum;
553 };
554 
555 extern const struct seq_operations ipv6_route_seq_ops;
556 
557 int call_fib6_notifier(struct notifier_block *nb,
558 		       enum fib_event_type event_type,
559 		       struct fib_notifier_info *info);
560 int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
561 			struct fib_notifier_info *info);
562 
563 int __net_init fib6_notifier_init(struct net *net);
564 void __net_exit fib6_notifier_exit(struct net *net);
565 
566 unsigned int fib6_tables_seq_read(struct net *net);
567 int fib6_tables_dump(struct net *net, struct notifier_block *nb,
568 		     struct netlink_ext_ack *extack);
569 
570 void fib6_update_sernum(struct net *net, struct fib6_info *rt);
571 void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
572 void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);
573 
574 void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
575 static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
576 {
577 	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
578 }
579 void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
580 			    bool offload, bool trap, bool offload_failed);
581 
582 #if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
583 struct bpf_iter__ipv6_route {
584 	__bpf_md_ptr(struct bpf_iter_meta *, meta);
585 	__bpf_md_ptr(struct fib6_info *, rt);
586 };
587 #endif
588 
589 INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_output(struct net *net,
590 					     struct fib6_table *table,
591 					     struct flowi6 *fl6,
592 					     const struct sk_buff *skb,
593 					     int flags));
594 INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_input(struct net *net,
595 					     struct fib6_table *table,
596 					     struct flowi6 *fl6,
597 					     const struct sk_buff *skb,
598 					     int flags));
599 INDIRECT_CALLABLE_DECLARE(struct rt6_info *__ip6_route_redirect(struct net *net,
600 					     struct fib6_table *table,
601 					     struct flowi6 *fl6,
602 					     const struct sk_buff *skb,
603 					     int flags));
604 INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_lookup(struct net *net,
605 					     struct fib6_table *table,
606 					     struct flowi6 *fl6,
607 					     const struct sk_buff *skb,
608 					     int flags));
609 static inline struct rt6_info *pol_lookup_func(pol_lookup_t lookup,
610 						struct net *net,
611 						struct fib6_table *table,
612 						struct flowi6 *fl6,
613 						const struct sk_buff *skb,
614 						int flags)
615 {
616 	return INDIRECT_CALL_4(lookup,
617 			       ip6_pol_route_output,
618 			       ip6_pol_route_input,
619 			       ip6_pol_route_lookup,
620 			       __ip6_route_redirect,
621 			       net, table, fl6, skb, flags);
622 }
623 
624 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
625 static inline bool fib6_has_custom_rules(const struct net *net)
626 {
627 	return net->ipv6.fib6_has_custom_rules;
628 }
629 
630 int fib6_rules_init(void);
631 void fib6_rules_cleanup(void);
632 bool fib6_rule_default(const struct fib_rule *rule);
633 int fib6_rules_dump(struct net *net, struct notifier_block *nb,
634 		    struct netlink_ext_ack *extack);
635 unsigned int fib6_rules_seq_read(struct net *net);
636 
637 static inline bool fib6_rules_early_flow_dissect(struct net *net,
638 						 struct sk_buff *skb,
639 						 struct flowi6 *fl6,
640 						 struct flow_keys *flkeys)
641 {
642 	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
643 
644 	if (!net->ipv6.fib6_rules_require_fldissect)
645 		return false;
646 
647 	memset(flkeys, 0, sizeof(*flkeys));
648 	__skb_flow_dissect(net, skb, &flow_keys_dissector,
649 			   flkeys, NULL, 0, 0, 0, flag);
650 
651 	fl6->fl6_sport = flkeys->ports.src;
652 	fl6->fl6_dport = flkeys->ports.dst;
653 	fl6->flowi6_proto = flkeys->basic.ip_proto;
654 
655 	return true;
656 }
657 #else
658 static inline bool fib6_has_custom_rules(const struct net *net)
659 {
660 	return false;
661 }
662 static inline int               fib6_rules_init(void)
663 {
664 	return 0;
665 }
666 static inline void              fib6_rules_cleanup(void)
667 {
668 	return ;
669 }
670 static inline bool fib6_rule_default(const struct fib_rule *rule)
671 {
672 	return true;
673 }
674 static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb,
675 				  struct netlink_ext_ack *extack)
676 {
677 	return 0;
678 }
679 static inline unsigned int fib6_rules_seq_read(struct net *net)
680 {
681 	return 0;
682 }
683 static inline bool fib6_rules_early_flow_dissect(struct net *net,
684 						 struct sk_buff *skb,
685 						 struct flowi6 *fl6,
686 						 struct flow_keys *flkeys)
687 {
688 	return false;
689 }
690 #endif
691 #endif
692