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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
v5.9
  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
 24#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 25#define FIB6_TABLE_HASHSZ 256
 26#else
 27#define FIB6_TABLE_HASHSZ 1
 28#endif
 29
 30#define RT6_DEBUG 2
 31
 32#if RT6_DEBUG >= 3
 33#define RT6_TRACE(x...) pr_debug(x)
 34#else
 35#define RT6_TRACE(x...) do { ; } while (0)
 36#endif
 37
 38struct rt6_info;
 39struct fib6_info;
 40
 41struct fib6_config {
 42	u32		fc_table;
 43	u32		fc_metric;
 44	int		fc_dst_len;
 45	int		fc_src_len;
 46	int		fc_ifindex;
 47	u32		fc_flags;
 48	u32		fc_protocol;
 49	u16		fc_type;        /* only 8 bits are used */
 50	u16		fc_delete_all_nh : 1,
 51			fc_ignore_dev_down:1,
 52			__unused : 14;
 53	u32		fc_nh_id;
 54
 55	struct in6_addr	fc_dst;
 56	struct in6_addr	fc_src;
 57	struct in6_addr	fc_prefsrc;
 58	struct in6_addr	fc_gateway;
 59
 60	unsigned long	fc_expires;
 61	struct nlattr	*fc_mx;
 62	int		fc_mx_len;
 63	int		fc_mp_len;
 64	struct nlattr	*fc_mp;
 65
 66	struct nl_info	fc_nlinfo;
 67	struct nlattr	*fc_encap;
 68	u16		fc_encap_type;
 69	bool		fc_is_fdb;
 70};
 71
 72struct fib6_node {
 73	struct fib6_node __rcu	*parent;
 74	struct fib6_node __rcu	*left;
 75	struct fib6_node __rcu	*right;
 76#ifdef CONFIG_IPV6_SUBTREES
 77	struct fib6_node __rcu	*subtree;
 78#endif
 79	struct fib6_info __rcu	*leaf;
 80
 81	__u16			fn_bit;		/* bit key */
 82	__u16			fn_flags;
 83	int			fn_sernum;
 84	struct fib6_info __rcu	*rr_ptr;
 85	struct rcu_head		rcu;
 86};
 87
 88struct fib6_gc_args {
 89	int			timeout;
 90	int			more;
 91};
 92
 93#ifndef CONFIG_IPV6_SUBTREES
 94#define FIB6_SUBTREE(fn)	NULL
 95
 96static inline bool fib6_routes_require_src(const struct net *net)
 97{
 98	return false;
 99}
100
101static inline void fib6_routes_require_src_inc(struct net *net) {}
102static inline void fib6_routes_require_src_dec(struct net *net) {}
103
104#else
105
106static inline bool fib6_routes_require_src(const struct net *net)
107{
108	return net->ipv6.fib6_routes_require_src > 0;
109}
110
111static inline void fib6_routes_require_src_inc(struct net *net)
112{
113	net->ipv6.fib6_routes_require_src++;
114}
115
116static inline void fib6_routes_require_src_dec(struct net *net)
117{
118	net->ipv6.fib6_routes_require_src--;
119}
120
121#define FIB6_SUBTREE(fn)	(rcu_dereference_protected((fn)->subtree, 1))
122#endif
123
124/*
125 *	routing information
126 *
127 */
128
129struct rt6key {
130	struct in6_addr	addr;
131	int		plen;
132};
133
134struct fib6_table;
135
136struct rt6_exception_bucket {
137	struct hlist_head	chain;
138	int			depth;
139};
140
141struct rt6_exception {
142	struct hlist_node	hlist;
143	struct rt6_info		*rt6i;
144	unsigned long		stamp;
145	struct rcu_head		rcu;
146};
147
148#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
149#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
150#define FIB6_MAX_DEPTH 5
151
152struct fib6_nh {
153	struct fib_nh_common	nh_common;
154
155#ifdef CONFIG_IPV6_ROUTER_PREF
156	unsigned long		last_probe;
157#endif
158
159	struct rt6_info * __percpu *rt6i_pcpu;
160	struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
161};
162
163struct fib6_info {
164	struct fib6_table		*fib6_table;
165	struct fib6_info __rcu		*fib6_next;
166	struct fib6_node __rcu		*fib6_node;
167
168	/* Multipath routes:
169	 * siblings is a list of fib6_info that have the same metric/weight,
170	 * destination, but not the same gateway. nsiblings is just a cache
171	 * to speed up lookup.
172	 */
173	union {
174		struct list_head	fib6_siblings;
175		struct list_head	nh_list;
176	};
177	unsigned int			fib6_nsiblings;
178
179	refcount_t			fib6_ref;
180	unsigned long			expires;
181	struct dst_metrics		*fib6_metrics;
182#define fib6_pmtu		fib6_metrics->metrics[RTAX_MTU-1]
183
184	struct rt6key			fib6_dst;
185	u32				fib6_flags;
186	struct rt6key			fib6_src;
187	struct rt6key			fib6_prefsrc;
188
189	u32				fib6_metric;
190	u8				fib6_protocol;
191	u8				fib6_type;
192	u8				should_flush:1,
193					dst_nocount:1,
194					dst_nopolicy:1,
 
195					fib6_destroying:1,
196					offload:1,
197					trap:1,
198					unused:2;
199
200	struct rcu_head			rcu;
201	struct nexthop			*nh;
202	struct fib6_nh			fib6_nh[];
203};
204
205struct rt6_info {
206	struct dst_entry		dst;
207	struct fib6_info __rcu		*from;
208	int				sernum;
209
210	struct rt6key			rt6i_dst;
211	struct rt6key			rt6i_src;
212	struct in6_addr			rt6i_gateway;
213	struct inet6_dev		*rt6i_idev;
214	u32				rt6i_flags;
215
216	struct list_head		rt6i_uncached;
217	struct uncached_list		*rt6i_uncached_list;
218
219	/* more non-fragment space at head required */
220	unsigned short			rt6i_nfheader_len;
221};
222
223struct fib6_result {
224	struct fib6_nh		*nh;
225	struct fib6_info	*f6i;
226	u32			fib6_flags;
227	u8			fib6_type;
228	struct rt6_info		*rt6;
229};
230
231#define for_each_fib6_node_rt_rcu(fn)					\
232	for (rt = rcu_dereference((fn)->leaf); rt;			\
233	     rt = rcu_dereference(rt->fib6_next))
234
235#define for_each_fib6_walker_rt(w)					\
236	for (rt = (w)->leaf; rt;					\
237	     rt = rcu_dereference_protected(rt->fib6_next, 1))
238
239static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
240{
241	return ((struct 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
249static inline void fib6_clean_expires(struct fib6_info *f6i)
250{
251	f6i->fib6_flags &= ~RTF_EXPIRES;
252	f6i->expires = 0;
253}
254
255static inline void fib6_set_expires(struct fib6_info *f6i,
256				    unsigned long expires)
257{
258	f6i->expires = expires;
259	f6i->fib6_flags |= RTF_EXPIRES;
260}
261
262static inline bool fib6_check_expired(const struct fib6_info *f6i)
263{
264	if (f6i->fib6_flags & RTF_EXPIRES)
265		return time_after(jiffies, f6i->expires);
266	return false;
267}
268
269/* Function to safely get fn->sernum for passed in rt
270 * and store result in passed in cookie.
271 * Return true if we can get cookie safely
272 * Return false if not
273 */
274static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
275					u32 *cookie)
276{
277	struct fib6_node *fn;
278	bool status = false;
279
280	fn = rcu_dereference(f6i->fib6_node);
281
282	if (fn) {
283		*cookie = fn->fn_sernum;
284		/* pairs with smp_wmb() in fib6_update_sernum_upto_root() */
285		smp_rmb();
286		status = true;
287	}
288
289	return status;
290}
291
292static inline u32 rt6_get_cookie(const struct rt6_info *rt)
293{
294	struct fib6_info *from;
295	u32 cookie = 0;
296
297	if (rt->sernum)
298		return rt->sernum;
299
300	rcu_read_lock();
301
302	from = rcu_dereference(rt->from);
303	if (from)
304		fib6_get_cookie_safe(from, &cookie);
305
306	rcu_read_unlock();
307
308	return cookie;
309}
310
311static inline void ip6_rt_put(struct rt6_info *rt)
312{
313	/* dst_release() accepts a NULL parameter.
314	 * We rely on dst being first structure in struct rt6_info
315	 */
316	BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
317	dst_release(&rt->dst);
318}
319
320struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
321void fib6_info_destroy_rcu(struct rcu_head *head);
322
323static inline void fib6_info_hold(struct fib6_info *f6i)
324{
325	refcount_inc(&f6i->fib6_ref);
326}
327
328static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
329{
330	return refcount_inc_not_zero(&f6i->fib6_ref);
331}
332
333static inline void fib6_info_release(struct fib6_info *f6i)
334{
335	if (f6i && refcount_dec_and_test(&f6i->fib6_ref))
336		call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
337}
338
339static inline void fib6_info_hw_flags_set(struct fib6_info *f6i, bool offload,
340					  bool trap)
341{
342	f6i->offload = offload;
343	f6i->trap = trap;
344}
345
346enum fib6_walk_state {
347#ifdef CONFIG_IPV6_SUBTREES
348	FWS_S,
349#endif
350	FWS_L,
351	FWS_R,
352	FWS_C,
353	FWS_U
354};
355
356struct fib6_walker {
357	struct list_head lh;
358	struct fib6_node *root, *node;
359	struct fib6_info *leaf;
360	enum fib6_walk_state state;
361	unsigned int skip;
362	unsigned int count;
363	unsigned int skip_in_node;
364	int (*func)(struct fib6_walker *);
365	void *args;
366};
367
368struct rt6_statistics {
369	__u32		fib_nodes;		/* all fib6 nodes */
370	__u32		fib_route_nodes;	/* intermediate nodes */
371	__u32		fib_rt_entries;		/* rt entries in fib table */
372	__u32		fib_rt_cache;		/* cached rt entries in exception table */
373	__u32		fib_discarded_routes;	/* total number of routes delete */
374
375	/* The following stats are not protected by any lock */
376	atomic_t	fib_rt_alloc;		/* total number of routes alloced */
377	atomic_t	fib_rt_uncache;		/* rt entries in uncached list */
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;
398#define RT6_TABLE_HAS_DFLT_ROUTER	BIT(0)
399};
400
401#define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
402#define RT6_TABLE_MAIN		RT_TABLE_MAIN
403#define RT6_TABLE_DFLT		RT6_TABLE_MAIN
404#define RT6_TABLE_INFO		RT6_TABLE_MAIN
405#define RT6_TABLE_PREFIX	RT6_TABLE_MAIN
406
407#ifdef CONFIG_IPV6_MULTIPLE_TABLES
408#define FIB6_TABLE_MIN		1
409#define FIB6_TABLE_MAX		RT_TABLE_MAX
410#define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
411#else
412#define FIB6_TABLE_MIN		RT_TABLE_MAIN
413#define FIB6_TABLE_MAX		FIB6_TABLE_MIN
414#define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
415#endif
416
417typedef struct rt6_info *(*pol_lookup_t)(struct net *,
418					 struct fib6_table *,
419					 struct flowi6 *,
420					 const struct sk_buff *, int);
421
422struct fib6_entry_notifier_info {
423	struct fib_notifier_info info; /* must be first */
424	struct fib6_info *rt;
425	unsigned int nsiblings;
426};
427
428/*
429 *	exported functions
430 */
431
432struct fib6_table *fib6_get_table(struct net *net, u32 id);
433struct fib6_table *fib6_new_table(struct net *net, u32 id);
434struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
435				   const struct sk_buff *skb,
436				   int flags, pol_lookup_t lookup);
437
438/* called with rcu lock held; can return error pointer
439 * caller needs to select path
440 */
441int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
442		struct fib6_result *res, int flags);
443
444/* called with rcu lock held; caller needs to select path */
445int fib6_table_lookup(struct net *net, struct fib6_table *table,
446		      int oif, struct flowi6 *fl6, struct fib6_result *res,
447		      int strict);
448
449void fib6_select_path(const struct net *net, struct fib6_result *res,
450		      struct flowi6 *fl6, int oif, bool have_oif_match,
451		      const struct sk_buff *skb, int strict);
452struct fib6_node *fib6_node_lookup(struct fib6_node *root,
453				   const struct in6_addr *daddr,
454				   const struct in6_addr *saddr);
455
456struct fib6_node *fib6_locate(struct fib6_node *root,
457			      const struct in6_addr *daddr, int dst_len,
458			      const struct in6_addr *saddr, int src_len,
459			      bool exact_match);
460
461void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
462		    void *arg);
463void fib6_clean_all_skip_notify(struct net *net,
464				int (*func)(struct fib6_info *, void *arg),
465				void *arg);
466
467int fib6_add(struct fib6_node *root, struct fib6_info *rt,
468	     struct nl_info *info, struct netlink_ext_ack *extack);
469int fib6_del(struct fib6_info *rt, struct nl_info *info);
470
471static inline
472void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
473{
474	const struct fib6_info *from;
475
476	rcu_read_lock();
477
478	from = rcu_dereference(rt->from);
479	if (from) {
480		*addr = from->fib6_prefsrc.addr;
481	} else {
482		struct in6_addr in6_zero = {};
483
484		*addr = in6_zero;
485	}
486
487	rcu_read_unlock();
488}
489
490int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
491		 struct fib6_config *cfg, gfp_t gfp_flags,
492		 struct netlink_ext_ack *extack);
493void fib6_nh_release(struct fib6_nh *fib6_nh);
494
495int call_fib6_entry_notifiers(struct net *net,
496			      enum fib_event_type event_type,
497			      struct fib6_info *rt,
498			      struct netlink_ext_ack *extack);
499int call_fib6_multipath_entry_notifiers(struct net *net,
500					enum fib_event_type event_type,
501					struct fib6_info *rt,
502					unsigned int nsiblings,
503					struct netlink_ext_ack *extack);
504int call_fib6_entry_notifiers_replace(struct net *net, struct fib6_info *rt);
505void fib6_rt_update(struct net *net, struct fib6_info *rt,
506		    struct nl_info *info);
507void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
508		     unsigned int flags);
509
510void fib6_run_gc(unsigned long expires, struct net *net, bool force);
511
512void fib6_gc_cleanup(void);
513
514int fib6_init(void);
515
516struct ipv6_route_iter {
517	struct seq_net_private p;
518	struct fib6_walker w;
519	loff_t skip;
520	struct fib6_table *tbl;
521	int sernum;
522};
523
524extern const struct seq_operations ipv6_route_seq_ops;
525
526int call_fib6_notifier(struct notifier_block *nb,
527		       enum fib_event_type event_type,
528		       struct fib_notifier_info *info);
529int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
530			struct fib_notifier_info *info);
531
532int __net_init fib6_notifier_init(struct net *net);
533void __net_exit fib6_notifier_exit(struct net *net);
534
535unsigned int fib6_tables_seq_read(struct net *net);
536int fib6_tables_dump(struct net *net, struct notifier_block *nb,
537		     struct netlink_ext_ack *extack);
538
539void fib6_update_sernum(struct net *net, struct fib6_info *rt);
540void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
541void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);
542
543void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
544static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
545{
546	return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
547}
548
549#if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
550struct bpf_iter__ipv6_route {
551	__bpf_md_ptr(struct bpf_iter_meta *, meta);
552	__bpf_md_ptr(struct fib6_info *, rt);
553};
554#endif
555
556INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_output(struct net *net,
557					     struct fib6_table *table,
558					     struct flowi6 *fl6,
559					     const struct sk_buff *skb,
560					     int flags));
561INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_input(struct net *net,
562					     struct fib6_table *table,
563					     struct flowi6 *fl6,
564					     const struct sk_buff *skb,
565					     int flags));
566INDIRECT_CALLABLE_DECLARE(struct rt6_info *__ip6_route_redirect(struct net *net,
567					     struct fib6_table *table,
568					     struct flowi6 *fl6,
569					     const struct sk_buff *skb,
570					     int flags));
571INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_lookup(struct net *net,
572					     struct fib6_table *table,
573					     struct flowi6 *fl6,
574					     const struct sk_buff *skb,
575					     int flags));
576static inline struct rt6_info *pol_lookup_func(pol_lookup_t lookup,
577						struct net *net,
578						struct fib6_table *table,
579						struct flowi6 *fl6,
580						const struct sk_buff *skb,
581						int flags)
582{
583	return INDIRECT_CALL_4(lookup,
584			       ip6_pol_route_output,
585			       ip6_pol_route_input,
586			       ip6_pol_route_lookup,
587			       __ip6_route_redirect,
588			       net, table, fl6, skb, flags);
589}
590
591#ifdef CONFIG_IPV6_MULTIPLE_TABLES
592static inline bool fib6_has_custom_rules(const struct net *net)
593{
594	return net->ipv6.fib6_has_custom_rules;
595}
596
597int fib6_rules_init(void);
598void fib6_rules_cleanup(void);
599bool fib6_rule_default(const struct fib_rule *rule);
600int fib6_rules_dump(struct net *net, struct notifier_block *nb,
601		    struct netlink_ext_ack *extack);
602unsigned int fib6_rules_seq_read(struct net *net);
603
604static inline bool fib6_rules_early_flow_dissect(struct net *net,
605						 struct sk_buff *skb,
606						 struct flowi6 *fl6,
607						 struct flow_keys *flkeys)
608{
609	unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
610
611	if (!net->ipv6.fib6_rules_require_fldissect)
612		return false;
613
614	skb_flow_dissect_flow_keys(skb, flkeys, flag);
615	fl6->fl6_sport = flkeys->ports.src;
616	fl6->fl6_dport = flkeys->ports.dst;
617	fl6->flowi6_proto = flkeys->basic.ip_proto;
618
619	return true;
620}
621#else
622static inline bool fib6_has_custom_rules(const struct net *net)
623{
624	return false;
625}
626static inline int               fib6_rules_init(void)
627{
628	return 0;
629}
630static inline void              fib6_rules_cleanup(void)
631{
632	return ;
633}
634static inline bool fib6_rule_default(const struct fib_rule *rule)
635{
636	return true;
637}
638static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb,
639				  struct netlink_ext_ack *extack)
640{
641	return 0;
642}
643static inline unsigned int fib6_rules_seq_read(struct net *net)
644{
645	return 0;
646}
647static inline bool fib6_rules_early_flow_dissect(struct net *net,
648						 struct sk_buff *skb,
649						 struct flowi6 *fl6,
650						 struct flow_keys *flkeys)
651{
652	return false;
653}
654#endif
655#endif