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v6.13.7
  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
 
 
 
 
 
 
 33struct rt6_info;
 34struct fib6_info;
 35
 36struct fib6_config {
 37	u32		fc_table;
 38	u32		fc_metric;
 39	int		fc_dst_len;
 40	int		fc_src_len;
 41	int		fc_ifindex;
 42	u32		fc_flags;
 43	u32		fc_protocol;
 44	u16		fc_type;        /* only 8 bits are used */
 45	u16		fc_delete_all_nh : 1,
 46			fc_ignore_dev_down:1,
 47			__unused : 14;
 48	u32		fc_nh_id;
 49
 50	struct in6_addr	fc_dst;
 51	struct in6_addr	fc_src;
 52	struct in6_addr	fc_prefsrc;
 53	struct in6_addr	fc_gateway;
 54
 55	unsigned long	fc_expires;
 56	struct nlattr	*fc_mx;
 57	int		fc_mx_len;
 58	int		fc_mp_len;
 59	struct nlattr	*fc_mp;
 60
 61	struct nl_info	fc_nlinfo;
 62	struct nlattr	*fc_encap;
 63	u16		fc_encap_type;
 64	bool		fc_is_fdb;
 65};
 66
 67struct fib6_node {
 68	struct fib6_node __rcu	*parent;
 69	struct fib6_node __rcu	*left;
 70	struct fib6_node __rcu	*right;
 71#ifdef CONFIG_IPV6_SUBTREES
 72	struct fib6_node __rcu	*subtree;
 73#endif
 74	struct fib6_info __rcu	*leaf;
 75
 76	__u16			fn_bit;		/* bit key */
 77	__u16			fn_flags;
 78	int			fn_sernum;
 79	struct fib6_info __rcu	*rr_ptr;
 80	struct rcu_head		rcu;
 81};
 82
 83struct fib6_gc_args {
 84	int			timeout;
 85	int			more;
 86};
 87
 88#ifndef CONFIG_IPV6_SUBTREES
 89#define FIB6_SUBTREE(fn)	NULL
 90
 91static inline bool fib6_routes_require_src(const struct net *net)
 92{
 93	return false;
 94}
 95
 96static inline void fib6_routes_require_src_inc(struct net *net) {}
 97static inline void fib6_routes_require_src_dec(struct net *net) {}
 98
 99#else
100
101static inline bool fib6_routes_require_src(const struct net *net)
102{
103	return net->ipv6.fib6_routes_require_src > 0;
104}
105
106static inline void fib6_routes_require_src_inc(struct net *net)
107{
108	net->ipv6.fib6_routes_require_src++;
109}
110
111static inline void fib6_routes_require_src_dec(struct net *net)
112{
113	net->ipv6.fib6_routes_require_src--;
114}
115
116#define FIB6_SUBTREE(fn)	(rcu_dereference_protected((fn)->subtree, 1))
117#endif
118
119/*
120 *	routing information
121 *
122 */
123
124struct rt6key {
125	struct in6_addr	addr;
126	int		plen;
127};
128
129struct fib6_table;
130
131struct rt6_exception_bucket {
132	struct hlist_head	chain;
133	int			depth;
134};
135
136struct rt6_exception {
137	struct hlist_node	hlist;
138	struct rt6_info		*rt6i;
139	unsigned long		stamp;
140	struct rcu_head		rcu;
141};
142
143#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
144#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
145#define FIB6_MAX_DEPTH 5
146
147struct fib6_nh {
148	struct fib_nh_common	nh_common;
149
150#ifdef CONFIG_IPV6_ROUTER_PREF
151	unsigned long		last_probe;
152#endif
153
154	struct rt6_info * __percpu *rt6i_pcpu;
155	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
156};
157
158struct fib6_info {
159	struct fib6_table		*fib6_table;
160	struct fib6_info __rcu		*fib6_next;
161	struct fib6_node __rcu		*fib6_node;
162
163	/* Multipath routes:
164	 * siblings is a list of fib6_info that have the same metric/weight,
165	 * destination, but not the same gateway. nsiblings is just a cache
166	 * to speed up lookup.
167	 */
168	union {
169		struct list_head	fib6_siblings;
170		struct list_head	nh_list;
171	};
172	unsigned int			fib6_nsiblings;
173
174	refcount_t			fib6_ref;
175	unsigned long			expires;
176
177	struct hlist_node		gc_link;
178
179	struct dst_metrics		*fib6_metrics;
180#define fib6_pmtu		fib6_metrics->metrics[RTAX_MTU-1]
181
182	struct rt6key			fib6_dst;
183	u32				fib6_flags;
184	struct rt6key			fib6_src;
185	struct rt6key			fib6_prefsrc;
186
187	u32				fib6_metric;
188	u8				fib6_protocol;
189	u8				fib6_type;
190
191	u8				offload;
192	u8				trap;
193	u8				offload_failed;
194
195	u8				should_flush:1,
196					dst_nocount:1,
197					dst_nopolicy:1,
 
198					fib6_destroying:1,
199					unused:4;
200
201	struct rcu_head			rcu;
202	struct nexthop			*nh;
203	struct fib6_nh			fib6_nh[];
204};
205
206struct rt6_info {
207	struct dst_entry		dst;
208	struct fib6_info __rcu		*from;
209	int				sernum;
210
211	struct rt6key			rt6i_dst;
212	struct rt6key			rt6i_src;
213	struct in6_addr			rt6i_gateway;
214	struct inet6_dev		*rt6i_idev;
215	u32				rt6i_flags;
216
 
 
 
217	/* more non-fragment space at head required */
218	unsigned short			rt6i_nfheader_len;
219};
220
221struct fib6_result {
222	struct fib6_nh		*nh;
223	struct fib6_info	*f6i;
224	u32			fib6_flags;
225	u8			fib6_type;
226	struct rt6_info		*rt6;
227};
228
229#define for_each_fib6_node_rt_rcu(fn)					\
230	for (rt = rcu_dereference((fn)->leaf); rt;			\
231	     rt = rcu_dereference(rt->fib6_next))
232
233#define for_each_fib6_walker_rt(w)					\
234	for (rt = (w)->leaf; rt;					\
235	     rt = rcu_dereference_protected(rt->fib6_next, 1))
236
237#define dst_rt6_info(_ptr) container_of_const(_ptr, struct rt6_info, dst)
238
239static inline struct inet6_dev *ip6_dst_idev(const struct dst_entry *dst)
240{
241	return dst_rt6_info(dst)->rt6i_idev;
242}
243
244static inline bool fib6_requires_src(const struct fib6_info *rt)
245{
246	return rt->fib6_src.plen > 0;
247}
248
249/* The callers should hold f6i->fib6_table->tb6_lock if a route has ever
250 * been added to a table before.
251 */
252static inline void fib6_clean_expires(struct fib6_info *f6i)
253{
254	f6i->fib6_flags &= ~RTF_EXPIRES;
255	f6i->expires = 0;
256}
257
258/* The callers should hold f6i->fib6_table->tb6_lock if a route has ever
259 * been added to a table before.
260 */
261static inline void fib6_set_expires(struct fib6_info *f6i,
262				    unsigned long expires)
263{
264	f6i->expires = expires;
265	f6i->fib6_flags |= RTF_EXPIRES;
266}
267
268static inline bool fib6_check_expired(const struct fib6_info *f6i)
269{
270	if (f6i->fib6_flags & RTF_EXPIRES)
271		return time_after(jiffies, f6i->expires);
272	return false;
273}
274
275/* Function to safely get fn->fn_sernum for passed in rt
276 * and store result in passed in cookie.
277 * Return true if we can get cookie safely
278 * Return false if not
279 */
280static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
281					u32 *cookie)
282{
283	struct fib6_node *fn;
284	bool status = false;
285
286	fn = rcu_dereference(f6i->fib6_node);
287
288	if (fn) {
289		*cookie = READ_ONCE(fn->fn_sernum);
290		/* pairs with smp_wmb() in __fib6_update_sernum_upto_root() */
291		smp_rmb();
292		status = true;
293	}
294
295	return status;
296}
297
298static inline u32 rt6_get_cookie(const struct rt6_info *rt)
299{
300	struct fib6_info *from;
301	u32 cookie = 0;
302
303	if (rt->sernum)
304		return rt->sernum;
305
306	rcu_read_lock();
307
308	from = rcu_dereference(rt->from);
309	if (from)
310		fib6_get_cookie_safe(from, &cookie);
311
312	rcu_read_unlock();
313
314	return cookie;
315}
316
317static inline void ip6_rt_put(struct rt6_info *rt)
318{
319	/* dst_release() accepts a NULL parameter.
320	 * We rely on dst being first structure in struct rt6_info
321	 */
322	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
323	dst_release(&rt->dst);
324}
325
326struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
327void fib6_info_destroy_rcu(struct rcu_head *head);
328
329static inline void fib6_info_hold(struct fib6_info *f6i)
330{
331	refcount_inc(&f6i->fib6_ref);
332}
333
334static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
335{
336	return refcount_inc_not_zero(&f6i->fib6_ref);
337}
338
339static inline void fib6_info_release(struct fib6_info *f6i)
340{
341	if (f6i && refcount_dec_and_test(&f6i->fib6_ref)) {
342		DEBUG_NET_WARN_ON_ONCE(!hlist_unhashed(&f6i->gc_link));
343		call_rcu_hurry(&f6i->rcu, fib6_info_destroy_rcu);
344	}
345}
346
347enum fib6_walk_state {
348#ifdef CONFIG_IPV6_SUBTREES
349	FWS_S,
350#endif
351	FWS_L,
352	FWS_R,
353	FWS_C,
354	FWS_U
355};
356
357struct fib6_walker {
358	struct list_head lh;
359	struct fib6_node *root, *node;
360	struct fib6_info *leaf;
361	enum fib6_walk_state state;
362	unsigned int skip;
363	unsigned int count;
364	unsigned int skip_in_node;
365	int (*func)(struct fib6_walker *);
366	void *args;
367};
368
369struct rt6_statistics {
370	__u32		fib_nodes;		/* all fib6 nodes */
371	__u32		fib_route_nodes;	/* intermediate nodes */
372	__u32		fib_rt_entries;		/* rt entries in fib table */
373	__u32		fib_rt_cache;		/* cached rt entries in exception table */
374	__u32		fib_discarded_routes;	/* total number of routes delete */
375
376	/* The following stat is not protected by any lock */
377	atomic_t	fib_rt_alloc;		/* total number of routes alloced */
 
378};
379
380#define RTN_TL_ROOT	0x0001
381#define RTN_ROOT	0x0002		/* tree root node		*/
382#define RTN_RTINFO	0x0004		/* node with valid routing info	*/
383
384/*
385 *	priority levels (or metrics)
386 *
387 */
388
389
390struct fib6_table {
391	struct hlist_node	tb6_hlist;
392	u32			tb6_id;
393	spinlock_t		tb6_lock;
394	struct fib6_node	tb6_root;
395	struct inet_peer_base	tb6_peers;
396	unsigned int		flags;
397	unsigned int		fib_seq; /* writes protected by rtnl_mutex */
398	struct hlist_head       tb6_gc_hlist;	/* GC candidates */
399#define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)
400};
401
402#define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
403#define RT6_TABLE_MAIN		RT_TABLE_MAIN
404#define RT6_TABLE_DFLT		RT6_TABLE_MAIN
405#define RT6_TABLE_INFO		RT6_TABLE_MAIN
406#define RT6_TABLE_PREFIX	RT6_TABLE_MAIN
407
408#ifdef CONFIG_IPV6_MULTIPLE_TABLES
409#define FIB6_TABLE_MIN		1
410#define FIB6_TABLE_MAX		RT_TABLE_MAX
411#define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
412#else
413#define FIB6_TABLE_MIN		RT_TABLE_MAIN
414#define FIB6_TABLE_MAX		FIB6_TABLE_MIN
415#define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
416#endif
417
418typedef struct rt6_info *(*pol_lookup_t)(struct net *,
419					 struct fib6_table *,
420					 struct flowi6 *,
421					 const struct sk_buff *, int);
422
423struct fib6_entry_notifier_info {
424	struct fib_notifier_info info; /* must be first */
425	struct fib6_info *rt;
426	unsigned int nsiblings;
427};
428
429/*
430 *	exported functions
431 */
432
433struct fib6_table *fib6_get_table(struct net *net, u32 id);
434struct fib6_table *fib6_new_table(struct net *net, u32 id);
435struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
436				   const struct sk_buff *skb,
437				   int flags, pol_lookup_t lookup);
438
439/* called with rcu lock held; can return error pointer
440 * caller needs to select path
441 */
442int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
443		struct fib6_result *res, int flags);
444
445/* called with rcu lock held; caller needs to select path */
446int fib6_table_lookup(struct net *net, struct fib6_table *table,
447		      int oif, struct flowi6 *fl6, struct fib6_result *res,
448		      int strict);
449
450void fib6_select_path(const struct net *net, struct fib6_result *res,
451		      struct flowi6 *fl6, int oif, bool have_oif_match,
452		      const struct sk_buff *skb, int strict);
453struct fib6_node *fib6_node_lookup(struct fib6_node *root,
454				   const struct in6_addr *daddr,
455				   const struct in6_addr *saddr);
456
457struct fib6_node *fib6_locate(struct fib6_node *root,
458			      const struct in6_addr *daddr, int dst_len,
459			      const struct in6_addr *saddr, int src_len,
460			      bool exact_match);
461
462void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
463		    void *arg);
464void fib6_clean_all_skip_notify(struct net *net,
465				int (*func)(struct fib6_info *, void *arg),
466				void *arg);
467
468int fib6_add(struct fib6_node *root, struct fib6_info *rt,
469	     struct nl_info *info, struct netlink_ext_ack *extack);
470int fib6_del(struct fib6_info *rt, struct nl_info *info);
471
472static inline
473void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
474{
475	const struct fib6_info *from;
476
477	rcu_read_lock();
478
479	from = rcu_dereference(rt->from);
480	if (from)
481		*addr = from->fib6_prefsrc.addr;
482	else
483		*addr = in6addr_any;
 
 
 
484
485	rcu_read_unlock();
486}
487
488int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
489		 struct fib6_config *cfg, gfp_t gfp_flags,
490		 struct netlink_ext_ack *extack);
491void fib6_nh_release(struct fib6_nh *fib6_nh);
492void fib6_nh_release_dsts(struct fib6_nh *fib6_nh);
493
494int call_fib6_entry_notifiers(struct net *net,
495			      enum fib_event_type event_type,
496			      struct fib6_info *rt,
497			      struct netlink_ext_ack *extack);
498int call_fib6_multipath_entry_notifiers(struct net *net,
499					enum fib_event_type event_type,
500					struct fib6_info *rt,
501					unsigned int nsiblings,
502					struct netlink_ext_ack *extack);
503int call_fib6_entry_notifiers_replace(struct net *net, struct fib6_info *rt);
504void fib6_rt_update(struct net *net, struct fib6_info *rt,
505		    struct nl_info *info);
506void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
507		     unsigned int flags);
508
509void fib6_run_gc(unsigned long expires, struct net *net, bool force);
510
511void fib6_gc_cleanup(void);
512
513int fib6_init(void);
514
515/* Add the route to the gc list if it is not already there
516 *
517 * The callers should hold f6i->fib6_table->tb6_lock.
518 */
519static inline void fib6_add_gc_list(struct fib6_info *f6i)
520{
521	/* If fib6_node is null, the f6i is not in (or removed from) the
522	 * table.
523	 *
524	 * There is a gap between finding the f6i from the table and
525	 * calling this function without the protection of the tb6_lock.
526	 * This check makes sure the f6i is not added to the gc list when
527	 * it is not on the table.
528	 */
529	if (!rcu_dereference_protected(f6i->fib6_node,
530				       lockdep_is_held(&f6i->fib6_table->tb6_lock)))
531		return;
532
533	if (hlist_unhashed(&f6i->gc_link))
534		hlist_add_head(&f6i->gc_link, &f6i->fib6_table->tb6_gc_hlist);
535}
536
537/* Remove the route from the gc list if it is on the list.
538 *
539 * The callers should hold f6i->fib6_table->tb6_lock.
540 */
541static inline void fib6_remove_gc_list(struct fib6_info *f6i)
542{
543	if (!hlist_unhashed(&f6i->gc_link))
544		hlist_del_init(&f6i->gc_link);
545}
546
547struct 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
555extern const struct seq_operations ipv6_route_seq_ops;
556
557int call_fib6_notifier(struct notifier_block *nb,
558		       enum fib_event_type event_type,
559		       struct fib_notifier_info *info);
560int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
561			struct fib_notifier_info *info);
562
563int __net_init fib6_notifier_init(struct net *net);
564void __net_exit fib6_notifier_exit(struct net *net);
565
566unsigned int fib6_tables_seq_read(const struct net *net);
567int fib6_tables_dump(struct net *net, struct notifier_block *nb,
568		     struct netlink_ext_ack *extack);
569
570void fib6_update_sernum(struct net *net, struct fib6_info *rt);
571void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
572void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);
573
574void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
575static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
576{
577	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
578}
579void 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)
583struct 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
589INDIRECT_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));
594INDIRECT_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));
599INDIRECT_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));
604INDIRECT_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));
609static 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
625static inline bool fib6_has_custom_rules(const struct net *net)
626{
627	return net->ipv6.fib6_has_custom_rules;
628}
629
630int fib6_rules_init(void);
631void fib6_rules_cleanup(void);
632bool fib6_rule_default(const struct fib_rule *rule);
633int fib6_rules_dump(struct net *net, struct notifier_block *nb,
634		    struct netlink_ext_ack *extack);
635unsigned int fib6_rules_seq_read(const struct net *net);
636
637static 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
658static inline bool fib6_has_custom_rules(const struct net *net)
659{
660	return false;
661}
662static inline int               fib6_rules_init(void)
663{
664	return 0;
665}
666static inline void              fib6_rules_cleanup(void)
667{
668	return ;
669}
670static inline bool fib6_rule_default(const struct fib_rule *rule)
671{
672	return true;
673}
674static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb,
675				  struct netlink_ext_ack *extack)
676{
677	return 0;
678}
679static inline unsigned int fib6_rules_seq_read(const struct net *net)
680{
681	return 0;
682}
683static 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
v5.4
  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
 23#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 24#define FIB6_TABLE_HASHSZ 256
 25#else
 26#define FIB6_TABLE_HASHSZ 1
 27#endif
 28
 29#define RT6_DEBUG 2
 30
 31#if RT6_DEBUG >= 3
 32#define RT6_TRACE(x...) pr_debug(x)
 33#else
 34#define RT6_TRACE(x...) do { ; } while (0)
 35#endif
 36
 37struct rt6_info;
 38struct fib6_info;
 39
 40struct fib6_config {
 41	u32		fc_table;
 42	u32		fc_metric;
 43	int		fc_dst_len;
 44	int		fc_src_len;
 45	int		fc_ifindex;
 46	u32		fc_flags;
 47	u32		fc_protocol;
 48	u16		fc_type;        /* only 8 bits are used */
 49	u16		fc_delete_all_nh : 1,
 50			fc_ignore_dev_down:1,
 51			__unused : 14;
 52	u32		fc_nh_id;
 53
 54	struct in6_addr	fc_dst;
 55	struct in6_addr	fc_src;
 56	struct in6_addr	fc_prefsrc;
 57	struct in6_addr	fc_gateway;
 58
 59	unsigned long	fc_expires;
 60	struct nlattr	*fc_mx;
 61	int		fc_mx_len;
 62	int		fc_mp_len;
 63	struct nlattr	*fc_mp;
 64
 65	struct nl_info	fc_nlinfo;
 66	struct nlattr	*fc_encap;
 67	u16		fc_encap_type;
 
 68};
 69
 70struct fib6_node {
 71	struct fib6_node __rcu	*parent;
 72	struct fib6_node __rcu	*left;
 73	struct fib6_node __rcu	*right;
 74#ifdef CONFIG_IPV6_SUBTREES
 75	struct fib6_node __rcu	*subtree;
 76#endif
 77	struct fib6_info __rcu	*leaf;
 78
 79	__u16			fn_bit;		/* bit key */
 80	__u16			fn_flags;
 81	int			fn_sernum;
 82	struct fib6_info __rcu	*rr_ptr;
 83	struct rcu_head		rcu;
 84};
 85
 86struct fib6_gc_args {
 87	int			timeout;
 88	int			more;
 89};
 90
 91#ifndef CONFIG_IPV6_SUBTREES
 92#define FIB6_SUBTREE(fn)	NULL
 
 
 
 
 
 
 
 
 
 93#else
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 94#define FIB6_SUBTREE(fn)	(rcu_dereference_protected((fn)->subtree, 1))
 95#endif
 96
 97/*
 98 *	routing information
 99 *
100 */
101
102struct rt6key {
103	struct in6_addr	addr;
104	int		plen;
105};
106
107struct fib6_table;
108
109struct rt6_exception_bucket {
110	struct hlist_head	chain;
111	int			depth;
112};
113
114struct rt6_exception {
115	struct hlist_node	hlist;
116	struct rt6_info		*rt6i;
117	unsigned long		stamp;
118	struct rcu_head		rcu;
119};
120
121#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
122#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
123#define FIB6_MAX_DEPTH 5
124
125struct fib6_nh {
126	struct fib_nh_common	nh_common;
127
128#ifdef CONFIG_IPV6_ROUTER_PREF
129	unsigned long		last_probe;
130#endif
131
132	struct rt6_info * __percpu *rt6i_pcpu;
133	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
134};
135
136struct fib6_info {
137	struct fib6_table		*fib6_table;
138	struct fib6_info __rcu		*fib6_next;
139	struct fib6_node __rcu		*fib6_node;
140
141	/* Multipath routes:
142	 * siblings is a list of fib6_info that have the the same metric/weight,
143	 * destination, but not the same gateway. nsiblings is just a cache
144	 * to speed up lookup.
145	 */
146	union {
147		struct list_head	fib6_siblings;
148		struct list_head	nh_list;
149	};
150	unsigned int			fib6_nsiblings;
151
152	refcount_t			fib6_ref;
153	unsigned long			expires;
 
 
 
154	struct dst_metrics		*fib6_metrics;
155#define fib6_pmtu		fib6_metrics->metrics[RTAX_MTU-1]
156
157	struct rt6key			fib6_dst;
158	u32				fib6_flags;
159	struct rt6key			fib6_src;
160	struct rt6key			fib6_prefsrc;
161
162	u32				fib6_metric;
163	u8				fib6_protocol;
164	u8				fib6_type;
 
 
 
 
 
165	u8				should_flush:1,
166					dst_nocount:1,
167					dst_nopolicy:1,
168					dst_host:1,
169					fib6_destroying:1,
170					unused:3;
171
172	struct rcu_head			rcu;
173	struct nexthop			*nh;
174	struct fib6_nh			fib6_nh[0];
175};
176
177struct rt6_info {
178	struct dst_entry		dst;
179	struct fib6_info __rcu		*from;
 
180
181	struct rt6key			rt6i_dst;
182	struct rt6key			rt6i_src;
183	struct in6_addr			rt6i_gateway;
184	struct inet6_dev		*rt6i_idev;
185	u32				rt6i_flags;
186
187	struct list_head		rt6i_uncached;
188	struct uncached_list		*rt6i_uncached_list;
189
190	/* more non-fragment space at head required */
191	unsigned short			rt6i_nfheader_len;
192};
193
194struct fib6_result {
195	struct fib6_nh		*nh;
196	struct fib6_info	*f6i;
197	u32			fib6_flags;
198	u8			fib6_type;
199	struct rt6_info		*rt6;
200};
201
202#define for_each_fib6_node_rt_rcu(fn)					\
203	for (rt = rcu_dereference((fn)->leaf); rt;			\
204	     rt = rcu_dereference(rt->fib6_next))
205
206#define for_each_fib6_walker_rt(w)					\
207	for (rt = (w)->leaf; rt;					\
208	     rt = rcu_dereference_protected(rt->fib6_next, 1))
209
210static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
 
 
211{
212	return ((struct rt6_info *)dst)->rt6i_idev;
213}
214
 
 
 
 
 
 
 
 
215static inline void fib6_clean_expires(struct fib6_info *f6i)
216{
217	f6i->fib6_flags &= ~RTF_EXPIRES;
218	f6i->expires = 0;
219}
220
 
 
 
221static inline void fib6_set_expires(struct fib6_info *f6i,
222				    unsigned long expires)
223{
224	f6i->expires = expires;
225	f6i->fib6_flags |= RTF_EXPIRES;
226}
227
228static inline bool fib6_check_expired(const struct fib6_info *f6i)
229{
230	if (f6i->fib6_flags & RTF_EXPIRES)
231		return time_after(jiffies, f6i->expires);
232	return false;
233}
234
235/* Function to safely get fn->sernum for passed in rt
236 * and store result in passed in cookie.
237 * Return true if we can get cookie safely
238 * Return false if not
239 */
240static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
241					u32 *cookie)
242{
243	struct fib6_node *fn;
244	bool status = false;
245
246	fn = rcu_dereference(f6i->fib6_node);
247
248	if (fn) {
249		*cookie = fn->fn_sernum;
250		/* pairs with smp_wmb() in fib6_update_sernum_upto_root() */
251		smp_rmb();
252		status = true;
253	}
254
255	return status;
256}
257
258static inline u32 rt6_get_cookie(const struct rt6_info *rt)
259{
260	struct fib6_info *from;
261	u32 cookie = 0;
262
 
 
 
263	rcu_read_lock();
264
265	from = rcu_dereference(rt->from);
266	if (from)
267		fib6_get_cookie_safe(from, &cookie);
268
269	rcu_read_unlock();
270
271	return cookie;
272}
273
274static inline void ip6_rt_put(struct rt6_info *rt)
275{
276	/* dst_release() accepts a NULL parameter.
277	 * We rely on dst being first structure in struct rt6_info
278	 */
279	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
280	dst_release(&rt->dst);
281}
282
283struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
284void fib6_info_destroy_rcu(struct rcu_head *head);
285
286static inline void fib6_info_hold(struct fib6_info *f6i)
287{
288	refcount_inc(&f6i->fib6_ref);
289}
290
291static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
292{
293	return refcount_inc_not_zero(&f6i->fib6_ref);
294}
295
296static inline void fib6_info_release(struct fib6_info *f6i)
297{
298	if (f6i && refcount_dec_and_test(&f6i->fib6_ref))
299		call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
 
 
300}
301
302enum fib6_walk_state {
303#ifdef CONFIG_IPV6_SUBTREES
304	FWS_S,
305#endif
306	FWS_L,
307	FWS_R,
308	FWS_C,
309	FWS_U
310};
311
312struct fib6_walker {
313	struct list_head lh;
314	struct fib6_node *root, *node;
315	struct fib6_info *leaf;
316	enum fib6_walk_state state;
317	unsigned int skip;
318	unsigned int count;
319	unsigned int skip_in_node;
320	int (*func)(struct fib6_walker *);
321	void *args;
322};
323
324struct rt6_statistics {
325	__u32		fib_nodes;		/* all fib6 nodes */
326	__u32		fib_route_nodes;	/* intermediate nodes */
327	__u32		fib_rt_entries;		/* rt entries in fib table */
328	__u32		fib_rt_cache;		/* cached rt entries in exception table */
329	__u32		fib_discarded_routes;	/* total number of routes delete */
330
331	/* The following stats are not protected by any lock */
332	atomic_t	fib_rt_alloc;		/* total number of routes alloced */
333	atomic_t	fib_rt_uncache;		/* rt entries in uncached list */
334};
335
336#define RTN_TL_ROOT	0x0001
337#define RTN_ROOT	0x0002		/* tree root node		*/
338#define RTN_RTINFO	0x0004		/* node with valid routing info	*/
339
340/*
341 *	priority levels (or metrics)
342 *
343 */
344
345
346struct fib6_table {
347	struct hlist_node	tb6_hlist;
348	u32			tb6_id;
349	spinlock_t		tb6_lock;
350	struct fib6_node	tb6_root;
351	struct inet_peer_base	tb6_peers;
352	unsigned int		flags;
353	unsigned int		fib_seq;
 
354#define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)
355};
356
357#define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
358#define RT6_TABLE_MAIN		RT_TABLE_MAIN
359#define RT6_TABLE_DFLT		RT6_TABLE_MAIN
360#define RT6_TABLE_INFO		RT6_TABLE_MAIN
361#define RT6_TABLE_PREFIX	RT6_TABLE_MAIN
362
363#ifdef CONFIG_IPV6_MULTIPLE_TABLES
364#define FIB6_TABLE_MIN		1
365#define FIB6_TABLE_MAX		RT_TABLE_MAX
366#define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
367#else
368#define FIB6_TABLE_MIN		RT_TABLE_MAIN
369#define FIB6_TABLE_MAX		FIB6_TABLE_MIN
370#define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
371#endif
372
373typedef struct rt6_info *(*pol_lookup_t)(struct net *,
374					 struct fib6_table *,
375					 struct flowi6 *,
376					 const struct sk_buff *, int);
377
378struct fib6_entry_notifier_info {
379	struct fib_notifier_info info; /* must be first */
380	struct fib6_info *rt;
381	unsigned int nsiblings;
382};
383
384/*
385 *	exported functions
386 */
387
388struct fib6_table *fib6_get_table(struct net *net, u32 id);
389struct fib6_table *fib6_new_table(struct net *net, u32 id);
390struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
391				   const struct sk_buff *skb,
392				   int flags, pol_lookup_t lookup);
393
394/* called with rcu lock held; can return error pointer
395 * caller needs to select path
396 */
397int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
398		struct fib6_result *res, int flags);
399
400/* called with rcu lock held; caller needs to select path */
401int fib6_table_lookup(struct net *net, struct fib6_table *table,
402		      int oif, struct flowi6 *fl6, struct fib6_result *res,
403		      int strict);
404
405void fib6_select_path(const struct net *net, struct fib6_result *res,
406		      struct flowi6 *fl6, int oif, bool have_oif_match,
407		      const struct sk_buff *skb, int strict);
408struct fib6_node *fib6_node_lookup(struct fib6_node *root,
409				   const struct in6_addr *daddr,
410				   const struct in6_addr *saddr);
411
412struct fib6_node *fib6_locate(struct fib6_node *root,
413			      const struct in6_addr *daddr, int dst_len,
414			      const struct in6_addr *saddr, int src_len,
415			      bool exact_match);
416
417void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
418		    void *arg);
419void fib6_clean_all_skip_notify(struct net *net,
420				int (*func)(struct fib6_info *, void *arg),
421				void *arg);
422
423int fib6_add(struct fib6_node *root, struct fib6_info *rt,
424	     struct nl_info *info, struct netlink_ext_ack *extack);
425int fib6_del(struct fib6_info *rt, struct nl_info *info);
426
427static inline
428void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
429{
430	const struct fib6_info *from;
431
432	rcu_read_lock();
433
434	from = rcu_dereference(rt->from);
435	if (from) {
436		*addr = from->fib6_prefsrc.addr;
437	} else {
438		struct in6_addr in6_zero = {};
439
440		*addr = in6_zero;
441	}
442
443	rcu_read_unlock();
444}
445
446int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
447		 struct fib6_config *cfg, gfp_t gfp_flags,
448		 struct netlink_ext_ack *extack);
449void fib6_nh_release(struct fib6_nh *fib6_nh);
 
450
451int call_fib6_entry_notifiers(struct net *net,
452			      enum fib_event_type event_type,
453			      struct fib6_info *rt,
454			      struct netlink_ext_ack *extack);
455int call_fib6_multipath_entry_notifiers(struct net *net,
456					enum fib_event_type event_type,
457					struct fib6_info *rt,
458					unsigned int nsiblings,
459					struct netlink_ext_ack *extack);
 
460void fib6_rt_update(struct net *net, struct fib6_info *rt,
461		    struct nl_info *info);
462void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
463		     unsigned int flags);
464
465void fib6_run_gc(unsigned long expires, struct net *net, bool force);
466
467void fib6_gc_cleanup(void);
468
469int fib6_init(void);
470
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
471struct ipv6_route_iter {
472	struct seq_net_private p;
473	struct fib6_walker w;
474	loff_t skip;
475	struct fib6_table *tbl;
476	int sernum;
477};
478
479extern const struct seq_operations ipv6_route_seq_ops;
480
481int call_fib6_notifier(struct notifier_block *nb, struct net *net,
482		       enum fib_event_type event_type,
483		       struct fib_notifier_info *info);
484int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
485			struct fib_notifier_info *info);
486
487int __net_init fib6_notifier_init(struct net *net);
488void __net_exit fib6_notifier_exit(struct net *net);
489
490unsigned int fib6_tables_seq_read(struct net *net);
491int fib6_tables_dump(struct net *net, struct notifier_block *nb);
 
492
493void fib6_update_sernum(struct net *net, struct fib6_info *rt);
494void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
495void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);
496
497void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
498static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
499{
500	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
501}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
502
503#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 
 
 
 
 
504int fib6_rules_init(void);
505void fib6_rules_cleanup(void);
506bool fib6_rule_default(const struct fib_rule *rule);
507int fib6_rules_dump(struct net *net, struct notifier_block *nb);
508unsigned int fib6_rules_seq_read(struct net *net);
 
509
510static inline bool fib6_rules_early_flow_dissect(struct net *net,
511						 struct sk_buff *skb,
512						 struct flowi6 *fl6,
513						 struct flow_keys *flkeys)
514{
515	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
516
517	if (!net->ipv6.fib6_rules_require_fldissect)
518		return false;
519
520	skb_flow_dissect_flow_keys(skb, flkeys, flag);
 
 
 
521	fl6->fl6_sport = flkeys->ports.src;
522	fl6->fl6_dport = flkeys->ports.dst;
523	fl6->flowi6_proto = flkeys->basic.ip_proto;
524
525	return true;
526}
527#else
 
 
 
 
528static inline int               fib6_rules_init(void)
529{
530	return 0;
531}
532static inline void              fib6_rules_cleanup(void)
533{
534	return ;
535}
536static inline bool fib6_rule_default(const struct fib_rule *rule)
537{
538	return true;
539}
540static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb)
 
541{
542	return 0;
543}
544static inline unsigned int fib6_rules_seq_read(struct net *net)
545{
546	return 0;
547}
548static inline bool fib6_rules_early_flow_dissect(struct net *net,
549						 struct sk_buff *skb,
550						 struct flowi6 *fl6,
551						 struct flow_keys *flkeys)
552{
553	return false;
554}
555#endif
556#endif