1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
12 #include <linux/ipv6_route.h>
13 #include <linux/rtnetlink.h>
14 #include <linux/spinlock.h>
15 #include <linux/notifier.h>
18 #include <net/ip_fib.h>
19 #include <net/netlink.h>
20 #include <net/inetpeer.h>
21 #include <net/fib_notifier.h>
23 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
24 #define FIB6_TABLE_HASHSZ 256
26 #define FIB6_TABLE_HASHSZ 1
32 #define RT6_TRACE(x...) pr_debug(x)
34 #define RT6_TRACE(x...) do { ; } while (0)
48 u16 fc_type
; /* only 8 bits are used */
49 u16 fc_delete_all_nh
: 1,
54 struct in6_addr fc_dst
;
55 struct in6_addr fc_src
;
56 struct in6_addr fc_prefsrc
;
57 struct in6_addr fc_gateway
;
59 unsigned long fc_expires
;
65 struct nl_info fc_nlinfo
;
66 struct nlattr
*fc_encap
;
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
;
77 struct fib6_info __rcu
*leaf
;
79 __u16 fn_bit
; /* bit key */
82 struct fib6_info __rcu
*rr_ptr
;
91 #ifndef CONFIG_IPV6_SUBTREES
92 #define FIB6_SUBTREE(fn) NULL
94 static inline bool fib6_routes_require_src(const struct net
*net
)
99 static inline void fib6_routes_require_src_inc(struct net
*net
) {}
100 static inline void fib6_routes_require_src_dec(struct net
*net
) {}
104 static inline bool fib6_routes_require_src(const struct net
*net
)
106 return net
->ipv6
.fib6_routes_require_src
> 0;
109 static inline void fib6_routes_require_src_inc(struct net
*net
)
111 net
->ipv6
.fib6_routes_require_src
++;
114 static inline void fib6_routes_require_src_dec(struct net
*net
)
116 net
->ipv6
.fib6_routes_require_src
--;
119 #define FIB6_SUBTREE(fn) (rcu_dereference_protected((fn)->subtree, 1))
123 * routing information
128 struct in6_addr addr
;
134 struct rt6_exception_bucket
{
135 struct hlist_head chain
;
139 struct rt6_exception
{
140 struct hlist_node hlist
;
141 struct rt6_info
*rt6i
;
146 #define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
147 #define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
148 #define FIB6_MAX_DEPTH 5
151 struct fib_nh_common nh_common
;
153 #ifdef CONFIG_IPV6_ROUTER_PREF
154 unsigned long last_probe
;
157 struct rt6_info
* __percpu
*rt6i_pcpu
;
158 struct rt6_exception_bucket __rcu
*rt6i_exception_bucket
;
162 struct fib6_table
*fib6_table
;
163 struct fib6_info __rcu
*fib6_next
;
164 struct fib6_node __rcu
*fib6_node
;
167 * siblings is a list of fib6_info that have the the same metric/weight,
168 * destination, but not the same gateway. nsiblings is just a cache
169 * to speed up lookup.
172 struct list_head fib6_siblings
;
173 struct list_head nh_list
;
175 unsigned int fib6_nsiblings
;
178 unsigned long expires
;
179 struct dst_metrics
*fib6_metrics
;
180 #define fib6_pmtu fib6_metrics->metrics[RTAX_MTU-1]
182 struct rt6key fib6_dst
;
184 struct rt6key fib6_src
;
185 struct rt6key fib6_prefsrc
;
200 struct fib6_nh fib6_nh
[];
204 struct dst_entry dst
;
205 struct fib6_info __rcu
*from
;
208 struct rt6key rt6i_dst
;
209 struct rt6key rt6i_src
;
210 struct in6_addr rt6i_gateway
;
211 struct inet6_dev
*rt6i_idev
;
214 struct list_head rt6i_uncached
;
215 struct uncached_list
*rt6i_uncached_list
;
217 /* more non-fragment space at head required */
218 unsigned short rt6i_nfheader_len
;
223 struct fib6_info
*f6i
;
226 struct rt6_info
*rt6
;
229 #define for_each_fib6_node_rt_rcu(fn) \
230 for (rt = rcu_dereference((fn)->leaf); rt; \
231 rt = rcu_dereference(rt->fib6_next))
233 #define for_each_fib6_walker_rt(w) \
234 for (rt = (w)->leaf; rt; \
235 rt = rcu_dereference_protected(rt->fib6_next, 1))
237 static inline struct inet6_dev
*ip6_dst_idev(struct dst_entry
*dst
)
239 return ((struct rt6_info
*)dst
)->rt6i_idev
;
242 static inline bool fib6_requires_src(const struct fib6_info
*rt
)
244 return rt
->fib6_src
.plen
> 0;
247 static inline void fib6_clean_expires(struct fib6_info
*f6i
)
249 f6i
->fib6_flags
&= ~RTF_EXPIRES
;
253 static inline void fib6_set_expires(struct fib6_info
*f6i
,
254 unsigned long expires
)
256 f6i
->expires
= expires
;
257 f6i
->fib6_flags
|= RTF_EXPIRES
;
260 static inline bool fib6_check_expired(const struct fib6_info
*f6i
)
262 if (f6i
->fib6_flags
& RTF_EXPIRES
)
263 return time_after(jiffies
, f6i
->expires
);
267 /* Function to safely get fn->sernum for passed in rt
268 * and store result in passed in cookie.
269 * Return true if we can get cookie safely
270 * Return false if not
272 static inline bool fib6_get_cookie_safe(const struct fib6_info
*f6i
,
275 struct fib6_node
*fn
;
278 fn
= rcu_dereference(f6i
->fib6_node
);
281 *cookie
= fn
->fn_sernum
;
282 /* pairs with smp_wmb() in fib6_update_sernum_upto_root() */
290 static inline u32
rt6_get_cookie(const struct rt6_info
*rt
)
292 struct fib6_info
*from
;
300 from
= rcu_dereference(rt
->from
);
302 fib6_get_cookie_safe(from
, &cookie
);
309 static inline void ip6_rt_put(struct rt6_info
*rt
)
311 /* dst_release() accepts a NULL parameter.
312 * We rely on dst being first structure in struct rt6_info
314 BUILD_BUG_ON(offsetof(struct rt6_info
, dst
) != 0);
315 dst_release(&rt
->dst
);
318 struct fib6_info
*fib6_info_alloc(gfp_t gfp_flags
, bool with_fib6_nh
);
319 void fib6_info_destroy_rcu(struct rcu_head
*head
);
321 static inline void fib6_info_hold(struct fib6_info
*f6i
)
323 refcount_inc(&f6i
->fib6_ref
);
326 static inline bool fib6_info_hold_safe(struct fib6_info
*f6i
)
328 return refcount_inc_not_zero(&f6i
->fib6_ref
);
331 static inline void fib6_info_release(struct fib6_info
*f6i
)
333 if (f6i
&& refcount_dec_and_test(&f6i
->fib6_ref
))
334 call_rcu(&f6i
->rcu
, fib6_info_destroy_rcu
);
337 static inline void fib6_info_hw_flags_set(struct fib6_info
*f6i
, bool offload
,
340 f6i
->offload
= offload
;
344 enum fib6_walk_state
{
345 #ifdef CONFIG_IPV6_SUBTREES
356 struct fib6_node
*root
, *node
;
357 struct fib6_info
*leaf
;
358 enum fib6_walk_state state
;
361 unsigned int skip_in_node
;
362 int (*func
)(struct fib6_walker
*);
366 struct rt6_statistics
{
367 __u32 fib_nodes
; /* all fib6 nodes */
368 __u32 fib_route_nodes
; /* intermediate nodes */
369 __u32 fib_rt_entries
; /* rt entries in fib table */
370 __u32 fib_rt_cache
; /* cached rt entries in exception table */
371 __u32 fib_discarded_routes
; /* total number of routes delete */
373 /* The following stats are not protected by any lock */
374 atomic_t fib_rt_alloc
; /* total number of routes alloced */
375 atomic_t fib_rt_uncache
; /* rt entries in uncached list */
378 #define RTN_TL_ROOT 0x0001
379 #define RTN_ROOT 0x0002 /* tree root node */
380 #define RTN_RTINFO 0x0004 /* node with valid routing info */
383 * priority levels (or metrics)
389 struct hlist_node tb6_hlist
;
392 struct fib6_node tb6_root
;
393 struct inet_peer_base tb6_peers
;
395 unsigned int fib_seq
;
396 #define RT6_TABLE_HAS_DFLT_ROUTER BIT(0)
399 #define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
400 #define RT6_TABLE_MAIN RT_TABLE_MAIN
401 #define RT6_TABLE_DFLT RT6_TABLE_MAIN
402 #define RT6_TABLE_INFO RT6_TABLE_MAIN
403 #define RT6_TABLE_PREFIX RT6_TABLE_MAIN
405 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
406 #define FIB6_TABLE_MIN 1
407 #define FIB6_TABLE_MAX RT_TABLE_MAX
408 #define RT6_TABLE_LOCAL RT_TABLE_LOCAL
410 #define FIB6_TABLE_MIN RT_TABLE_MAIN
411 #define FIB6_TABLE_MAX FIB6_TABLE_MIN
412 #define RT6_TABLE_LOCAL RT6_TABLE_MAIN
415 typedef struct rt6_info
*(*pol_lookup_t
)(struct net
*,
418 const struct sk_buff
*, int);
420 struct fib6_entry_notifier_info
{
421 struct fib_notifier_info info
; /* must be first */
422 struct fib6_info
*rt
;
423 unsigned int nsiblings
;
430 struct fib6_table
*fib6_get_table(struct net
*net
, u32 id
);
431 struct fib6_table
*fib6_new_table(struct net
*net
, u32 id
);
432 struct dst_entry
*fib6_rule_lookup(struct net
*net
, struct flowi6
*fl6
,
433 const struct sk_buff
*skb
,
434 int flags
, pol_lookup_t lookup
);
436 /* called with rcu lock held; can return error pointer
437 * caller needs to select path
439 int fib6_lookup(struct net
*net
, int oif
, struct flowi6
*fl6
,
440 struct fib6_result
*res
, int flags
);
442 /* called with rcu lock held; caller needs to select path */
443 int fib6_table_lookup(struct net
*net
, struct fib6_table
*table
,
444 int oif
, struct flowi6
*fl6
, struct fib6_result
*res
,
447 void fib6_select_path(const struct net
*net
, struct fib6_result
*res
,
448 struct flowi6
*fl6
, int oif
, bool have_oif_match
,
449 const struct sk_buff
*skb
, int strict
);
450 struct fib6_node
*fib6_node_lookup(struct fib6_node
*root
,
451 const struct in6_addr
*daddr
,
452 const struct in6_addr
*saddr
);
454 struct fib6_node
*fib6_locate(struct fib6_node
*root
,
455 const struct in6_addr
*daddr
, int dst_len
,
456 const struct in6_addr
*saddr
, int src_len
,
459 void fib6_clean_all(struct net
*net
, int (*func
)(struct fib6_info
*, void *arg
),
461 void fib6_clean_all_skip_notify(struct net
*net
,
462 int (*func
)(struct fib6_info
*, void *arg
),
465 int fib6_add(struct fib6_node
*root
, struct fib6_info
*rt
,
466 struct nl_info
*info
, struct netlink_ext_ack
*extack
);
467 int fib6_del(struct fib6_info
*rt
, struct nl_info
*info
);
470 void rt6_get_prefsrc(const struct rt6_info
*rt
, struct in6_addr
*addr
)
472 const struct fib6_info
*from
;
476 from
= rcu_dereference(rt
->from
);
478 *addr
= from
->fib6_prefsrc
.addr
;
480 struct in6_addr in6_zero
= {};
488 int 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
);
491 void fib6_nh_release(struct fib6_nh
*fib6_nh
);
493 int call_fib6_entry_notifiers(struct net
*net
,
494 enum fib_event_type event_type
,
495 struct fib6_info
*rt
,
496 struct netlink_ext_ack
*extack
);
497 int call_fib6_multipath_entry_notifiers(struct net
*net
,
498 enum fib_event_type event_type
,
499 struct fib6_info
*rt
,
500 unsigned int nsiblings
,
501 struct netlink_ext_ack
*extack
);
502 int call_fib6_entry_notifiers_replace(struct net
*net
, struct fib6_info
*rt
);
503 void fib6_rt_update(struct net
*net
, struct fib6_info
*rt
,
504 struct nl_info
*info
);
505 void inet6_rt_notify(int event
, struct fib6_info
*rt
, struct nl_info
*info
,
508 void fib6_run_gc(unsigned long expires
, struct net
*net
, bool force
);
510 void fib6_gc_cleanup(void);
514 struct ipv6_route_iter
{
515 struct seq_net_private p
;
516 struct fib6_walker w
;
518 struct fib6_table
*tbl
;
522 extern const struct seq_operations ipv6_route_seq_ops
;
524 int call_fib6_notifier(struct notifier_block
*nb
,
525 enum fib_event_type event_type
,
526 struct fib_notifier_info
*info
);
527 int call_fib6_notifiers(struct net
*net
, enum fib_event_type event_type
,
528 struct fib_notifier_info
*info
);
530 int __net_init
fib6_notifier_init(struct net
*net
);
531 void __net_exit
fib6_notifier_exit(struct net
*net
);
533 unsigned int fib6_tables_seq_read(struct net
*net
);
534 int fib6_tables_dump(struct net
*net
, struct notifier_block
*nb
,
535 struct netlink_ext_ack
*extack
);
537 void fib6_update_sernum(struct net
*net
, struct fib6_info
*rt
);
538 void fib6_update_sernum_upto_root(struct net
*net
, struct fib6_info
*rt
);
539 void fib6_update_sernum_stub(struct net
*net
, struct fib6_info
*f6i
);
541 void fib6_metric_set(struct fib6_info
*f6i
, int metric
, u32 val
);
542 static inline bool fib6_metric_locked(struct fib6_info
*f6i
, int metric
)
544 return !!(f6i
->fib6_metrics
->metrics
[RTAX_LOCK
- 1] & (1 << metric
));
547 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
548 static inline bool fib6_has_custom_rules(const struct net
*net
)
550 return net
->ipv6
.fib6_has_custom_rules
;
553 int fib6_rules_init(void);
554 void fib6_rules_cleanup(void);
555 bool fib6_rule_default(const struct fib_rule
*rule
);
556 int fib6_rules_dump(struct net
*net
, struct notifier_block
*nb
,
557 struct netlink_ext_ack
*extack
);
558 unsigned int fib6_rules_seq_read(struct net
*net
);
560 static inline bool fib6_rules_early_flow_dissect(struct net
*net
,
563 struct flow_keys
*flkeys
)
565 unsigned int flag
= FLOW_DISSECTOR_F_STOP_AT_ENCAP
;
567 if (!net
->ipv6
.fib6_rules_require_fldissect
)
570 skb_flow_dissect_flow_keys(skb
, flkeys
, flag
);
571 fl6
->fl6_sport
= flkeys
->ports
.src
;
572 fl6
->fl6_dport
= flkeys
->ports
.dst
;
573 fl6
->flowi6_proto
= flkeys
->basic
.ip_proto
;
578 static inline bool fib6_has_custom_rules(const struct net
*net
)
582 static inline int fib6_rules_init(void)
586 static inline void fib6_rules_cleanup(void)
590 static inline bool fib6_rule_default(const struct fib_rule
*rule
)
594 static inline int fib6_rules_dump(struct net
*net
, struct notifier_block
*nb
,
595 struct netlink_ext_ack
*extack
)
599 static inline unsigned int fib6_rules_seq_read(struct net
*net
)
603 static inline bool fib6_rules_early_flow_dissect(struct net
*net
,
606 struct flow_keys
*flkeys
)