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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 offload_failed:1,
199 unused:1;
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 struct list_head rt6i_uncached;
218 struct uncached_list *rt6i_uncached_list;
219
220 /* more non-fragment space at head required */
221 unsigned short rt6i_nfheader_len;
222};
223
224struct fib6_result {
225 struct fib6_nh *nh;
226 struct fib6_info *f6i;
227 u32 fib6_flags;
228 u8 fib6_type;
229 struct rt6_info *rt6;
230};
231
232#define for_each_fib6_node_rt_rcu(fn) \
233 for (rt = rcu_dereference((fn)->leaf); rt; \
234 rt = rcu_dereference(rt->fib6_next))
235
236#define for_each_fib6_walker_rt(w) \
237 for (rt = (w)->leaf; rt; \
238 rt = rcu_dereference_protected(rt->fib6_next, 1))
239
240static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
241{
242 return ((struct rt6_info *)dst)->rt6i_idev;
243}
244
245static inline bool fib6_requires_src(const struct fib6_info *rt)
246{
247 return rt->fib6_src.plen > 0;
248}
249
250static inline void fib6_clean_expires(struct fib6_info *f6i)
251{
252 f6i->fib6_flags &= ~RTF_EXPIRES;
253 f6i->expires = 0;
254}
255
256static inline void fib6_set_expires(struct fib6_info *f6i,
257 unsigned long expires)
258{
259 f6i->expires = expires;
260 f6i->fib6_flags |= RTF_EXPIRES;
261}
262
263static inline bool fib6_check_expired(const struct fib6_info *f6i)
264{
265 if (f6i->fib6_flags & RTF_EXPIRES)
266 return time_after(jiffies, f6i->expires);
267 return false;
268}
269
270/* Function to safely get fn->fn_sernum for passed in rt
271 * and store result in passed in cookie.
272 * Return true if we can get cookie safely
273 * Return false if not
274 */
275static inline bool fib6_get_cookie_safe(const struct fib6_info *f6i,
276 u32 *cookie)
277{
278 struct fib6_node *fn;
279 bool status = false;
280
281 fn = rcu_dereference(f6i->fib6_node);
282
283 if (fn) {
284 *cookie = fn->fn_sernum;
285 /* pairs with smp_wmb() in __fib6_update_sernum_upto_root() */
286 smp_rmb();
287 status = true;
288 }
289
290 return status;
291}
292
293static inline u32 rt6_get_cookie(const struct rt6_info *rt)
294{
295 struct fib6_info *from;
296 u32 cookie = 0;
297
298 if (rt->sernum)
299 return rt->sernum;
300
301 rcu_read_lock();
302
303 from = rcu_dereference(rt->from);
304 if (from)
305 fib6_get_cookie_safe(from, &cookie);
306
307 rcu_read_unlock();
308
309 return cookie;
310}
311
312static inline void ip6_rt_put(struct rt6_info *rt)
313{
314 /* dst_release() accepts a NULL parameter.
315 * We rely on dst being first structure in struct rt6_info
316 */
317 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
318 dst_release(&rt->dst);
319}
320
321struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh);
322void fib6_info_destroy_rcu(struct rcu_head *head);
323
324static inline void fib6_info_hold(struct fib6_info *f6i)
325{
326 refcount_inc(&f6i->fib6_ref);
327}
328
329static inline bool fib6_info_hold_safe(struct fib6_info *f6i)
330{
331 return refcount_inc_not_zero(&f6i->fib6_ref);
332}
333
334static inline void fib6_info_release(struct fib6_info *f6i)
335{
336 if (f6i && refcount_dec_and_test(&f6i->fib6_ref))
337 call_rcu(&f6i->rcu, fib6_info_destroy_rcu);
338}
339
340enum fib6_walk_state {
341#ifdef CONFIG_IPV6_SUBTREES
342 FWS_S,
343#endif
344 FWS_L,
345 FWS_R,
346 FWS_C,
347 FWS_U
348};
349
350struct fib6_walker {
351 struct list_head lh;
352 struct fib6_node *root, *node;
353 struct fib6_info *leaf;
354 enum fib6_walk_state state;
355 unsigned int skip;
356 unsigned int count;
357 unsigned int skip_in_node;
358 int (*func)(struct fib6_walker *);
359 void *args;
360};
361
362struct rt6_statistics {
363 __u32 fib_nodes; /* all fib6 nodes */
364 __u32 fib_route_nodes; /* intermediate nodes */
365 __u32 fib_rt_entries; /* rt entries in fib table */
366 __u32 fib_rt_cache; /* cached rt entries in exception table */
367 __u32 fib_discarded_routes; /* total number of routes delete */
368
369 /* The following stats are not protected by any lock */
370 atomic_t fib_rt_alloc; /* total number of routes alloced */
371 atomic_t fib_rt_uncache; /* rt entries in uncached list */
372};
373
374#define RTN_TL_ROOT 0x0001
375#define RTN_ROOT 0x0002 /* tree root node */
376#define RTN_RTINFO 0x0004 /* node with valid routing info */
377
378/*
379 * priority levels (or metrics)
380 *
381 */
382
383
384struct fib6_table {
385 struct hlist_node tb6_hlist;
386 u32 tb6_id;
387 spinlock_t tb6_lock;
388 struct fib6_node tb6_root;
389 struct inet_peer_base tb6_peers;
390 unsigned int flags;
391 unsigned int fib_seq;
392#define RT6_TABLE_HAS_DFLT_ROUTER BIT(0)
393};
394
395#define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
396#define RT6_TABLE_MAIN RT_TABLE_MAIN
397#define RT6_TABLE_DFLT RT6_TABLE_MAIN
398#define RT6_TABLE_INFO RT6_TABLE_MAIN
399#define RT6_TABLE_PREFIX RT6_TABLE_MAIN
400
401#ifdef CONFIG_IPV6_MULTIPLE_TABLES
402#define FIB6_TABLE_MIN 1
403#define FIB6_TABLE_MAX RT_TABLE_MAX
404#define RT6_TABLE_LOCAL RT_TABLE_LOCAL
405#else
406#define FIB6_TABLE_MIN RT_TABLE_MAIN
407#define FIB6_TABLE_MAX FIB6_TABLE_MIN
408#define RT6_TABLE_LOCAL RT6_TABLE_MAIN
409#endif
410
411typedef struct rt6_info *(*pol_lookup_t)(struct net *,
412 struct fib6_table *,
413 struct flowi6 *,
414 const struct sk_buff *, int);
415
416struct fib6_entry_notifier_info {
417 struct fib_notifier_info info; /* must be first */
418 struct fib6_info *rt;
419 unsigned int nsiblings;
420};
421
422/*
423 * exported functions
424 */
425
426struct fib6_table *fib6_get_table(struct net *net, u32 id);
427struct fib6_table *fib6_new_table(struct net *net, u32 id);
428struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
429 const struct sk_buff *skb,
430 int flags, pol_lookup_t lookup);
431
432/* called with rcu lock held; can return error pointer
433 * caller needs to select path
434 */
435int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
436 struct fib6_result *res, int flags);
437
438/* called with rcu lock held; caller needs to select path */
439int fib6_table_lookup(struct net *net, struct fib6_table *table,
440 int oif, struct flowi6 *fl6, struct fib6_result *res,
441 int strict);
442
443void fib6_select_path(const struct net *net, struct fib6_result *res,
444 struct flowi6 *fl6, int oif, bool have_oif_match,
445 const struct sk_buff *skb, int strict);
446struct fib6_node *fib6_node_lookup(struct fib6_node *root,
447 const struct in6_addr *daddr,
448 const struct in6_addr *saddr);
449
450struct fib6_node *fib6_locate(struct fib6_node *root,
451 const struct in6_addr *daddr, int dst_len,
452 const struct in6_addr *saddr, int src_len,
453 bool exact_match);
454
455void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *arg),
456 void *arg);
457void fib6_clean_all_skip_notify(struct net *net,
458 int (*func)(struct fib6_info *, void *arg),
459 void *arg);
460
461int fib6_add(struct fib6_node *root, struct fib6_info *rt,
462 struct nl_info *info, struct netlink_ext_ack *extack);
463int fib6_del(struct fib6_info *rt, struct nl_info *info);
464
465static inline
466void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
467{
468 const struct fib6_info *from;
469
470 rcu_read_lock();
471
472 from = rcu_dereference(rt->from);
473 if (from) {
474 *addr = from->fib6_prefsrc.addr;
475 } else {
476 struct in6_addr in6_zero = {};
477
478 *addr = in6_zero;
479 }
480
481 rcu_read_unlock();
482}
483
484int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
485 struct fib6_config *cfg, gfp_t gfp_flags,
486 struct netlink_ext_ack *extack);
487void fib6_nh_release(struct fib6_nh *fib6_nh);
488
489int call_fib6_entry_notifiers(struct net *net,
490 enum fib_event_type event_type,
491 struct fib6_info *rt,
492 struct netlink_ext_ack *extack);
493int call_fib6_multipath_entry_notifiers(struct net *net,
494 enum fib_event_type event_type,
495 struct fib6_info *rt,
496 unsigned int nsiblings,
497 struct netlink_ext_ack *extack);
498int call_fib6_entry_notifiers_replace(struct net *net, struct fib6_info *rt);
499void fib6_rt_update(struct net *net, struct fib6_info *rt,
500 struct nl_info *info);
501void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
502 unsigned int flags);
503
504void fib6_run_gc(unsigned long expires, struct net *net, bool force);
505
506void fib6_gc_cleanup(void);
507
508int fib6_init(void);
509
510struct ipv6_route_iter {
511 struct seq_net_private p;
512 struct fib6_walker w;
513 loff_t skip;
514 struct fib6_table *tbl;
515 int sernum;
516};
517
518extern const struct seq_operations ipv6_route_seq_ops;
519
520int call_fib6_notifier(struct notifier_block *nb,
521 enum fib_event_type event_type,
522 struct fib_notifier_info *info);
523int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
524 struct fib_notifier_info *info);
525
526int __net_init fib6_notifier_init(struct net *net);
527void __net_exit fib6_notifier_exit(struct net *net);
528
529unsigned int fib6_tables_seq_read(struct net *net);
530int fib6_tables_dump(struct net *net, struct notifier_block *nb,
531 struct netlink_ext_ack *extack);
532
533void fib6_update_sernum(struct net *net, struct fib6_info *rt);
534void fib6_update_sernum_upto_root(struct net *net, struct fib6_info *rt);
535void fib6_update_sernum_stub(struct net *net, struct fib6_info *f6i);
536
537void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val);
538static inline bool fib6_metric_locked(struct fib6_info *f6i, int metric)
539{
540 return !!(f6i->fib6_metrics->metrics[RTAX_LOCK - 1] & (1 << metric));
541}
542void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i,
543 bool offload, bool trap, bool offload_failed);
544
545#if IS_BUILTIN(CONFIG_IPV6) && defined(CONFIG_BPF_SYSCALL)
546struct bpf_iter__ipv6_route {
547 __bpf_md_ptr(struct bpf_iter_meta *, meta);
548 __bpf_md_ptr(struct fib6_info *, rt);
549};
550#endif
551
552INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_output(struct net *net,
553 struct fib6_table *table,
554 struct flowi6 *fl6,
555 const struct sk_buff *skb,
556 int flags));
557INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_input(struct net *net,
558 struct fib6_table *table,
559 struct flowi6 *fl6,
560 const struct sk_buff *skb,
561 int flags));
562INDIRECT_CALLABLE_DECLARE(struct rt6_info *__ip6_route_redirect(struct net *net,
563 struct fib6_table *table,
564 struct flowi6 *fl6,
565 const struct sk_buff *skb,
566 int flags));
567INDIRECT_CALLABLE_DECLARE(struct rt6_info *ip6_pol_route_lookup(struct net *net,
568 struct fib6_table *table,
569 struct flowi6 *fl6,
570 const struct sk_buff *skb,
571 int flags));
572static inline struct rt6_info *pol_lookup_func(pol_lookup_t lookup,
573 struct net *net,
574 struct fib6_table *table,
575 struct flowi6 *fl6,
576 const struct sk_buff *skb,
577 int flags)
578{
579 return INDIRECT_CALL_4(lookup,
580 ip6_pol_route_output,
581 ip6_pol_route_input,
582 ip6_pol_route_lookup,
583 __ip6_route_redirect,
584 net, table, fl6, skb, flags);
585}
586
587#ifdef CONFIG_IPV6_MULTIPLE_TABLES
588static inline bool fib6_has_custom_rules(const struct net *net)
589{
590 return net->ipv6.fib6_has_custom_rules;
591}
592
593int fib6_rules_init(void);
594void fib6_rules_cleanup(void);
595bool fib6_rule_default(const struct fib_rule *rule);
596int fib6_rules_dump(struct net *net, struct notifier_block *nb,
597 struct netlink_ext_ack *extack);
598unsigned int fib6_rules_seq_read(struct net *net);
599
600static inline bool fib6_rules_early_flow_dissect(struct net *net,
601 struct sk_buff *skb,
602 struct flowi6 *fl6,
603 struct flow_keys *flkeys)
604{
605 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
606
607 if (!net->ipv6.fib6_rules_require_fldissect)
608 return false;
609
610 skb_flow_dissect_flow_keys(skb, flkeys, flag);
611 fl6->fl6_sport = flkeys->ports.src;
612 fl6->fl6_dport = flkeys->ports.dst;
613 fl6->flowi6_proto = flkeys->basic.ip_proto;
614
615 return true;
616}
617#else
618static inline bool fib6_has_custom_rules(const struct net *net)
619{
620 return false;
621}
622static inline int fib6_rules_init(void)
623{
624 return 0;
625}
626static inline void fib6_rules_cleanup(void)
627{
628 return ;
629}
630static inline bool fib6_rule_default(const struct fib_rule *rule)
631{
632 return true;
633}
634static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb,
635 struct netlink_ext_ack *extack)
636{
637 return 0;
638}
639static inline unsigned int fib6_rules_seq_read(struct net *net)
640{
641 return 0;
642}
643static inline bool fib6_rules_early_flow_dissect(struct net *net,
644 struct sk_buff *skb,
645 struct flowi6 *fl6,
646 struct flow_keys *flkeys)
647{
648 return false;
649}
650#endif
651#endif
1/*
2 * Linux INET6 implementation
3 *
4 * Authors:
5 * Pedro Roque <roque@di.fc.ul.pt>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#ifndef _IP6_FIB_H
14#define _IP6_FIB_H
15
16#include <linux/ipv6_route.h>
17#include <linux/rtnetlink.h>
18#include <linux/spinlock.h>
19#include <linux/notifier.h>
20#include <net/dst.h>
21#include <net/flow.h>
22#include <net/netlink.h>
23#include <net/inetpeer.h>
24#include <net/fib_notifier.h>
25
26#ifdef CONFIG_IPV6_MULTIPLE_TABLES
27#define FIB6_TABLE_HASHSZ 256
28#else
29#define FIB6_TABLE_HASHSZ 1
30#endif
31
32#define RT6_DEBUG 2
33
34#if RT6_DEBUG >= 3
35#define RT6_TRACE(x...) pr_debug(x)
36#else
37#define RT6_TRACE(x...) do { ; } while (0)
38#endif
39
40struct rt6_info;
41
42struct 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 __unused : 15;
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 rt6_info __rcu *leaf;
78
79 __u16 fn_bit; /* bit key */
80 __u16 fn_flags;
81 int fn_sernum;
82 struct rt6_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
97struct mx6_config {
98 const u32 *mx;
99 DECLARE_BITMAP(mx_valid, RTAX_MAX);
100};
101
102/*
103 * routing information
104 *
105 */
106
107struct rt6key {
108 struct in6_addr addr;
109 int plen;
110};
111
112struct fib6_table;
113
114struct rt6_exception_bucket {
115 struct hlist_head chain;
116 int depth;
117};
118
119struct rt6_exception {
120 struct hlist_node hlist;
121 struct rt6_info *rt6i;
122 unsigned long stamp;
123 struct rcu_head rcu;
124};
125
126#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
127#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
128#define FIB6_MAX_DEPTH 5
129
130struct rt6_info {
131 struct dst_entry dst;
132 struct rt6_info __rcu *rt6_next;
133 struct rt6_info *from;
134
135 /*
136 * Tail elements of dst_entry (__refcnt etc.)
137 * and these elements (rarely used in hot path) are in
138 * the same cache line.
139 */
140 struct fib6_table *rt6i_table;
141 struct fib6_node __rcu *rt6i_node;
142
143 struct in6_addr rt6i_gateway;
144
145 /* Multipath routes:
146 * siblings is a list of rt6_info that have the the same metric/weight,
147 * destination, but not the same gateway. nsiblings is just a cache
148 * to speed up lookup.
149 */
150 struct list_head rt6i_siblings;
151 unsigned int rt6i_nsiblings;
152 atomic_t rt6i_nh_upper_bound;
153
154 atomic_t rt6i_ref;
155
156 unsigned int rt6i_nh_flags;
157
158 /* These are in a separate cache line. */
159 struct rt6key rt6i_dst ____cacheline_aligned_in_smp;
160 u32 rt6i_flags;
161 struct rt6key rt6i_src;
162 struct rt6key rt6i_prefsrc;
163
164 struct list_head rt6i_uncached;
165 struct uncached_list *rt6i_uncached_list;
166
167 struct inet6_dev *rt6i_idev;
168 struct rt6_info * __percpu *rt6i_pcpu;
169 struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
170
171 u32 rt6i_metric;
172 u32 rt6i_pmtu;
173 /* more non-fragment space at head required */
174 int rt6i_nh_weight;
175 unsigned short rt6i_nfheader_len;
176 u8 rt6i_protocol;
177 u8 exception_bucket_flushed:1,
178 should_flush:1,
179 unused:6;
180};
181
182#define for_each_fib6_node_rt_rcu(fn) \
183 for (rt = rcu_dereference((fn)->leaf); rt; \
184 rt = rcu_dereference(rt->rt6_next))
185
186#define for_each_fib6_walker_rt(w) \
187 for (rt = (w)->leaf; rt; \
188 rt = rcu_dereference_protected(rt->rt6_next, 1))
189
190static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
191{
192 return ((struct rt6_info *)dst)->rt6i_idev;
193}
194
195static inline void rt6_clean_expires(struct rt6_info *rt)
196{
197 rt->rt6i_flags &= ~RTF_EXPIRES;
198 rt->dst.expires = 0;
199}
200
201static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
202{
203 rt->dst.expires = expires;
204 rt->rt6i_flags |= RTF_EXPIRES;
205}
206
207static inline void rt6_update_expires(struct rt6_info *rt0, int timeout)
208{
209 struct rt6_info *rt;
210
211 for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES); rt = rt->from);
212 if (rt && rt != rt0)
213 rt0->dst.expires = rt->dst.expires;
214 dst_set_expires(&rt0->dst, timeout);
215 rt0->rt6i_flags |= RTF_EXPIRES;
216}
217
218/* Function to safely get fn->sernum for passed in rt
219 * and store result in passed in cookie.
220 * Return true if we can get cookie safely
221 * Return false if not
222 */
223static inline bool rt6_get_cookie_safe(const struct rt6_info *rt,
224 u32 *cookie)
225{
226 struct fib6_node *fn;
227 bool status = false;
228
229 rcu_read_lock();
230 fn = rcu_dereference(rt->rt6i_node);
231
232 if (fn) {
233 *cookie = fn->fn_sernum;
234 /* pairs with smp_wmb() in fib6_update_sernum_upto_root() */
235 smp_rmb();
236 status = true;
237 }
238
239 rcu_read_unlock();
240 return status;
241}
242
243static inline u32 rt6_get_cookie(const struct rt6_info *rt)
244{
245 u32 cookie = 0;
246
247 if (rt->rt6i_flags & RTF_PCPU ||
248 (unlikely(!list_empty(&rt->rt6i_uncached)) && rt->from))
249 rt = rt->from;
250
251 rt6_get_cookie_safe(rt, &cookie);
252
253 return cookie;
254}
255
256static inline void ip6_rt_put(struct rt6_info *rt)
257{
258 /* dst_release() accepts a NULL parameter.
259 * We rely on dst being first structure in struct rt6_info
260 */
261 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
262 dst_release(&rt->dst);
263}
264
265void rt6_free_pcpu(struct rt6_info *non_pcpu_rt);
266
267static inline void rt6_hold(struct rt6_info *rt)
268{
269 atomic_inc(&rt->rt6i_ref);
270}
271
272static inline void rt6_release(struct rt6_info *rt)
273{
274 if (atomic_dec_and_test(&rt->rt6i_ref)) {
275 rt6_free_pcpu(rt);
276 dst_dev_put(&rt->dst);
277 dst_release(&rt->dst);
278 }
279}
280
281enum fib6_walk_state {
282#ifdef CONFIG_IPV6_SUBTREES
283 FWS_S,
284#endif
285 FWS_L,
286 FWS_R,
287 FWS_C,
288 FWS_U
289};
290
291struct fib6_walker {
292 struct list_head lh;
293 struct fib6_node *root, *node;
294 struct rt6_info *leaf;
295 enum fib6_walk_state state;
296 unsigned int skip;
297 unsigned int count;
298 int (*func)(struct fib6_walker *);
299 void *args;
300};
301
302struct rt6_statistics {
303 __u32 fib_nodes; /* all fib6 nodes */
304 __u32 fib_route_nodes; /* intermediate nodes */
305 __u32 fib_rt_entries; /* rt entries in fib table */
306 __u32 fib_rt_cache; /* cached rt entries in exception table */
307 __u32 fib_discarded_routes; /* total number of routes delete */
308
309 /* The following stats are not protected by any lock */
310 atomic_t fib_rt_alloc; /* total number of routes alloced */
311 atomic_t fib_rt_uncache; /* rt entries in uncached list */
312};
313
314#define RTN_TL_ROOT 0x0001
315#define RTN_ROOT 0x0002 /* tree root node */
316#define RTN_RTINFO 0x0004 /* node with valid routing info */
317
318/*
319 * priority levels (or metrics)
320 *
321 */
322
323
324struct fib6_table {
325 struct hlist_node tb6_hlist;
326 u32 tb6_id;
327 spinlock_t tb6_lock;
328 struct fib6_node tb6_root;
329 struct inet_peer_base tb6_peers;
330 unsigned int flags;
331 unsigned int fib_seq;
332#define RT6_TABLE_HAS_DFLT_ROUTER BIT(0)
333};
334
335#define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
336#define RT6_TABLE_MAIN RT_TABLE_MAIN
337#define RT6_TABLE_DFLT RT6_TABLE_MAIN
338#define RT6_TABLE_INFO RT6_TABLE_MAIN
339#define RT6_TABLE_PREFIX RT6_TABLE_MAIN
340
341#ifdef CONFIG_IPV6_MULTIPLE_TABLES
342#define FIB6_TABLE_MIN 1
343#define FIB6_TABLE_MAX RT_TABLE_MAX
344#define RT6_TABLE_LOCAL RT_TABLE_LOCAL
345#else
346#define FIB6_TABLE_MIN RT_TABLE_MAIN
347#define FIB6_TABLE_MAX FIB6_TABLE_MIN
348#define RT6_TABLE_LOCAL RT6_TABLE_MAIN
349#endif
350
351typedef struct rt6_info *(*pol_lookup_t)(struct net *,
352 struct fib6_table *,
353 struct flowi6 *,
354 const struct sk_buff *, int);
355
356struct fib6_entry_notifier_info {
357 struct fib_notifier_info info; /* must be first */
358 struct rt6_info *rt;
359};
360
361/*
362 * exported functions
363 */
364
365struct fib6_table *fib6_get_table(struct net *net, u32 id);
366struct fib6_table *fib6_new_table(struct net *net, u32 id);
367struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
368 const struct sk_buff *skb,
369 int flags, pol_lookup_t lookup);
370
371struct fib6_node *fib6_lookup(struct fib6_node *root,
372 const struct in6_addr *daddr,
373 const struct in6_addr *saddr);
374
375struct fib6_node *fib6_locate(struct fib6_node *root,
376 const struct in6_addr *daddr, int dst_len,
377 const struct in6_addr *saddr, int src_len,
378 bool exact_match);
379
380void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
381 void *arg);
382
383int fib6_add(struct fib6_node *root, struct rt6_info *rt,
384 struct nl_info *info, struct mx6_config *mxc,
385 struct netlink_ext_ack *extack);
386int fib6_del(struct rt6_info *rt, struct nl_info *info);
387
388void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
389 unsigned int flags);
390
391void fib6_run_gc(unsigned long expires, struct net *net, bool force);
392
393void fib6_gc_cleanup(void);
394
395int fib6_init(void);
396
397int ipv6_route_open(struct inode *inode, struct file *file);
398
399int call_fib6_notifier(struct notifier_block *nb, struct net *net,
400 enum fib_event_type event_type,
401 struct fib_notifier_info *info);
402int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
403 struct fib_notifier_info *info);
404
405int __net_init fib6_notifier_init(struct net *net);
406void __net_exit fib6_notifier_exit(struct net *net);
407
408unsigned int fib6_tables_seq_read(struct net *net);
409int fib6_tables_dump(struct net *net, struct notifier_block *nb);
410
411void fib6_update_sernum(struct rt6_info *rt);
412void fib6_update_sernum_upto_root(struct net *net, struct rt6_info *rt);
413
414#ifdef CONFIG_IPV6_MULTIPLE_TABLES
415int fib6_rules_init(void);
416void fib6_rules_cleanup(void);
417bool fib6_rule_default(const struct fib_rule *rule);
418int fib6_rules_dump(struct net *net, struct notifier_block *nb);
419unsigned int fib6_rules_seq_read(struct net *net);
420
421static inline bool fib6_rules_early_flow_dissect(struct net *net,
422 struct sk_buff *skb,
423 struct flowi6 *fl6,
424 struct flow_keys *flkeys)
425{
426 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
427
428 if (!net->ipv6.fib6_rules_require_fldissect)
429 return false;
430
431 skb_flow_dissect_flow_keys(skb, flkeys, flag);
432 fl6->fl6_sport = flkeys->ports.src;
433 fl6->fl6_dport = flkeys->ports.dst;
434 fl6->flowi6_proto = flkeys->basic.ip_proto;
435
436 return true;
437}
438#else
439static inline int fib6_rules_init(void)
440{
441 return 0;
442}
443static inline void fib6_rules_cleanup(void)
444{
445 return ;
446}
447static inline bool fib6_rule_default(const struct fib_rule *rule)
448{
449 return true;
450}
451static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb)
452{
453 return 0;
454}
455static inline unsigned int fib6_rules_seq_read(struct net *net)
456{
457 return 0;
458}
459static inline bool fib6_rules_early_flow_dissect(struct net *net,
460 struct sk_buff *skb,
461 struct flowi6 *fl6,
462 struct flow_keys *flkeys)
463{
464 return false;
465}
466#endif
467#endif