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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the Forwarding Information Base.
8 *
9 * Authors: A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 */
11
12#ifndef _NET_IP_FIB_H
13#define _NET_IP_FIB_H
14
15#include <net/flow.h>
16#include <linux/seq_file.h>
17#include <linux/rcupdate.h>
18#include <net/fib_notifier.h>
19#include <net/fib_rules.h>
20#include <net/inet_dscp.h>
21#include <net/inetpeer.h>
22#include <linux/percpu.h>
23#include <linux/notifier.h>
24#include <linux/refcount.h>
25#include <linux/ip.h>
26#include <linux/in_route.h>
27
28struct fib_config {
29 u8 fc_dst_len;
30 dscp_t fc_dscp;
31 u8 fc_protocol;
32 u8 fc_scope;
33 u8 fc_type;
34 u8 fc_gw_family;
35 /* 2 bytes unused */
36 u32 fc_table;
37 __be32 fc_dst;
38 union {
39 __be32 fc_gw4;
40 struct in6_addr fc_gw6;
41 };
42 int fc_oif;
43 u32 fc_flags;
44 u32 fc_priority;
45 __be32 fc_prefsrc;
46 u32 fc_nh_id;
47 struct nlattr *fc_mx;
48 struct rtnexthop *fc_mp;
49 int fc_mx_len;
50 int fc_mp_len;
51 u32 fc_flow;
52 u32 fc_nlflags;
53 struct nl_info fc_nlinfo;
54 struct nlattr *fc_encap;
55 u16 fc_encap_type;
56};
57
58struct fib_info;
59struct rtable;
60
61struct fib_nh_exception {
62 struct fib_nh_exception __rcu *fnhe_next;
63 int fnhe_genid;
64 __be32 fnhe_daddr;
65 u32 fnhe_pmtu;
66 bool fnhe_mtu_locked;
67 __be32 fnhe_gw;
68 unsigned long fnhe_expires;
69 struct rtable __rcu *fnhe_rth_input;
70 struct rtable __rcu *fnhe_rth_output;
71 unsigned long fnhe_stamp;
72 struct rcu_head rcu;
73};
74
75struct fnhe_hash_bucket {
76 struct fib_nh_exception __rcu *chain;
77};
78
79#define FNHE_HASH_SHIFT 11
80#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
81#define FNHE_RECLAIM_DEPTH 5
82
83struct fib_nh_common {
84 struct net_device *nhc_dev;
85 netdevice_tracker nhc_dev_tracker;
86 int nhc_oif;
87 unsigned char nhc_scope;
88 u8 nhc_family;
89 u8 nhc_gw_family;
90 unsigned char nhc_flags;
91 struct lwtunnel_state *nhc_lwtstate;
92
93 union {
94 __be32 ipv4;
95 struct in6_addr ipv6;
96 } nhc_gw;
97
98 int nhc_weight;
99 atomic_t nhc_upper_bound;
100
101 /* v4 specific, but allows fib6_nh with v4 routes */
102 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
103 struct rtable __rcu *nhc_rth_input;
104 struct fnhe_hash_bucket __rcu *nhc_exceptions;
105};
106
107struct fib_nh {
108 struct fib_nh_common nh_common;
109 struct hlist_node nh_hash;
110 struct fib_info *nh_parent;
111#ifdef CONFIG_IP_ROUTE_CLASSID
112 __u32 nh_tclassid;
113#endif
114 __be32 nh_saddr;
115 int nh_saddr_genid;
116#define fib_nh_family nh_common.nhc_family
117#define fib_nh_dev nh_common.nhc_dev
118#define fib_nh_dev_tracker nh_common.nhc_dev_tracker
119#define fib_nh_oif nh_common.nhc_oif
120#define fib_nh_flags nh_common.nhc_flags
121#define fib_nh_lws nh_common.nhc_lwtstate
122#define fib_nh_scope nh_common.nhc_scope
123#define fib_nh_gw_family nh_common.nhc_gw_family
124#define fib_nh_gw4 nh_common.nhc_gw.ipv4
125#define fib_nh_gw6 nh_common.nhc_gw.ipv6
126#define fib_nh_weight nh_common.nhc_weight
127#define fib_nh_upper_bound nh_common.nhc_upper_bound
128};
129
130/*
131 * This structure contains data shared by many of routes.
132 */
133
134struct nexthop;
135
136struct fib_info {
137 struct hlist_node fib_hash;
138 struct hlist_node fib_lhash;
139 struct list_head nh_list;
140 struct net *fib_net;
141 refcount_t fib_treeref;
142 refcount_t fib_clntref;
143 unsigned int fib_flags;
144 unsigned char fib_dead;
145 unsigned char fib_protocol;
146 unsigned char fib_scope;
147 unsigned char fib_type;
148 __be32 fib_prefsrc;
149 u32 fib_tb_id;
150 u32 fib_priority;
151 struct dst_metrics *fib_metrics;
152#define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
153#define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
154#define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
155#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
156 int fib_nhs;
157 bool fib_nh_is_v6;
158 bool nh_updated;
159 bool pfsrc_removed;
160 struct nexthop *nh;
161 struct rcu_head rcu;
162 struct fib_nh fib_nh[] __counted_by(fib_nhs);
163};
164
165
166#ifdef CONFIG_IP_MULTIPLE_TABLES
167struct fib_rule;
168#endif
169
170struct fib_table;
171struct fib_result {
172 __be32 prefix;
173 unsigned char prefixlen;
174 unsigned char nh_sel;
175 unsigned char type;
176 unsigned char scope;
177 u32 tclassid;
178 dscp_t dscp;
179 struct fib_nh_common *nhc;
180 struct fib_info *fi;
181 struct fib_table *table;
182 struct hlist_head *fa_head;
183};
184
185struct fib_result_nl {
186 __be32 fl_addr; /* To be looked up*/
187 u32 fl_mark;
188 unsigned char fl_tos;
189 unsigned char fl_scope;
190 unsigned char tb_id_in;
191
192 unsigned char tb_id; /* Results */
193 unsigned char prefixlen;
194 unsigned char nh_sel;
195 unsigned char type;
196 unsigned char scope;
197 int err;
198};
199
200#ifdef CONFIG_IP_MULTIPLE_TABLES
201#define FIB_TABLE_HASHSZ 256
202#else
203#define FIB_TABLE_HASHSZ 2
204#endif
205
206__be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
207 unsigned char scope);
208__be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
209
210#define FIB_RES_NHC(res) ((res).nhc)
211#define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
212#define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
213
214struct fib_rt_info {
215 struct fib_info *fi;
216 u32 tb_id;
217 __be32 dst;
218 int dst_len;
219 dscp_t dscp;
220 u8 type;
221 u8 offload:1,
222 trap:1,
223 offload_failed:1,
224 unused:5;
225};
226
227struct fib_entry_notifier_info {
228 struct fib_notifier_info info; /* must be first */
229 u32 dst;
230 int dst_len;
231 struct fib_info *fi;
232 dscp_t dscp;
233 u8 type;
234 u32 tb_id;
235};
236
237struct fib_nh_notifier_info {
238 struct fib_notifier_info info; /* must be first */
239 struct fib_nh *fib_nh;
240};
241
242int call_fib4_notifier(struct notifier_block *nb,
243 enum fib_event_type event_type,
244 struct fib_notifier_info *info);
245int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
246 struct fib_notifier_info *info);
247
248int __net_init fib4_notifier_init(struct net *net);
249void __net_exit fib4_notifier_exit(struct net *net);
250
251void fib_info_notify_update(struct net *net, struct nl_info *info);
252int fib_notify(struct net *net, struct notifier_block *nb,
253 struct netlink_ext_ack *extack);
254
255struct fib_table {
256 struct hlist_node tb_hlist;
257 u32 tb_id;
258 int tb_num_default;
259 struct rcu_head rcu;
260 unsigned long *tb_data;
261 unsigned long __data[];
262};
263
264struct fib_dump_filter {
265 u32 table_id;
266 /* filter_set is an optimization that an entry is set */
267 bool filter_set;
268 bool dump_routes;
269 bool dump_exceptions;
270 bool rtnl_held;
271 unsigned char protocol;
272 unsigned char rt_type;
273 unsigned int flags;
274 struct net_device *dev;
275};
276
277int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
278 struct fib_result *res, int fib_flags);
279int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
280 struct netlink_ext_ack *extack);
281int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
282 struct netlink_ext_ack *extack);
283int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
284 struct netlink_callback *cb, struct fib_dump_filter *filter);
285int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
286struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
287void fib_table_flush_external(struct fib_table *table);
288void fib_free_table(struct fib_table *tb);
289
290#ifndef CONFIG_IP_MULTIPLE_TABLES
291
292#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
293#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
294
295static inline struct fib_table *fib_get_table(struct net *net, u32 id)
296{
297 struct hlist_node *tb_hlist;
298 struct hlist_head *ptr;
299
300 ptr = id == RT_TABLE_LOCAL ?
301 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
302 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
303
304 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
305
306 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
307}
308
309static inline struct fib_table *fib_new_table(struct net *net, u32 id)
310{
311 return fib_get_table(net, id);
312}
313
314static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
315 struct fib_result *res, unsigned int flags)
316{
317 struct fib_table *tb;
318 int err = -ENETUNREACH;
319
320 rcu_read_lock();
321
322 tb = fib_get_table(net, RT_TABLE_MAIN);
323 if (tb)
324 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
325
326 if (err == -EAGAIN)
327 err = -ENETUNREACH;
328
329 rcu_read_unlock();
330
331 return err;
332}
333
334static inline bool fib4_has_custom_rules(const struct net *net)
335{
336 return false;
337}
338
339static inline bool fib4_rule_default(const struct fib_rule *rule)
340{
341 return true;
342}
343
344static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
345 struct netlink_ext_ack *extack)
346{
347 return 0;
348}
349
350static inline unsigned int fib4_rules_seq_read(const struct net *net)
351{
352 return 0;
353}
354
355static inline bool fib4_rules_early_flow_dissect(struct net *net,
356 struct sk_buff *skb,
357 struct flowi4 *fl4,
358 struct flow_keys *flkeys)
359{
360 return false;
361}
362#else /* CONFIG_IP_MULTIPLE_TABLES */
363int __net_init fib4_rules_init(struct net *net);
364void __net_exit fib4_rules_exit(struct net *net);
365
366struct fib_table *fib_new_table(struct net *net, u32 id);
367struct fib_table *fib_get_table(struct net *net, u32 id);
368
369int __fib_lookup(struct net *net, struct flowi4 *flp,
370 struct fib_result *res, unsigned int flags);
371
372static inline int fib_lookup(struct net *net, struct flowi4 *flp,
373 struct fib_result *res, unsigned int flags)
374{
375 struct fib_table *tb;
376 int err = -ENETUNREACH;
377
378 flags |= FIB_LOOKUP_NOREF;
379 if (net->ipv4.fib_has_custom_rules)
380 return __fib_lookup(net, flp, res, flags);
381
382 rcu_read_lock();
383
384 res->tclassid = 0;
385
386 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
387 if (tb)
388 err = fib_table_lookup(tb, flp, res, flags);
389
390 if (!err)
391 goto out;
392
393 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
394 if (tb)
395 err = fib_table_lookup(tb, flp, res, flags);
396
397out:
398 if (err == -EAGAIN)
399 err = -ENETUNREACH;
400
401 rcu_read_unlock();
402
403 return err;
404}
405
406static inline bool fib4_has_custom_rules(const struct net *net)
407{
408 return net->ipv4.fib_has_custom_rules;
409}
410
411bool fib4_rule_default(const struct fib_rule *rule);
412int fib4_rules_dump(struct net *net, struct notifier_block *nb,
413 struct netlink_ext_ack *extack);
414unsigned int fib4_rules_seq_read(const struct net *net);
415
416static inline bool fib4_rules_early_flow_dissect(struct net *net,
417 struct sk_buff *skb,
418 struct flowi4 *fl4,
419 struct flow_keys *flkeys)
420{
421 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
422
423 if (!net->ipv4.fib_rules_require_fldissect)
424 return false;
425
426 memset(flkeys, 0, sizeof(*flkeys));
427 __skb_flow_dissect(net, skb, &flow_keys_dissector,
428 flkeys, NULL, 0, 0, 0, flag);
429
430 fl4->fl4_sport = flkeys->ports.src;
431 fl4->fl4_dport = flkeys->ports.dst;
432 fl4->flowi4_proto = flkeys->basic.ip_proto;
433
434 return true;
435}
436
437#endif /* CONFIG_IP_MULTIPLE_TABLES */
438
439static inline bool fib_dscp_masked_match(dscp_t dscp, const struct flowi4 *fl4)
440{
441 return dscp == inet_dsfield_to_dscp(RT_TOS(fl4->flowi4_tos));
442}
443
444/* Exported by fib_frontend.c */
445extern const struct nla_policy rtm_ipv4_policy[];
446void ip_fib_init(void);
447int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
448 struct netlink_ext_ack *extack);
449__be32 fib_compute_spec_dst(struct sk_buff *skb);
450bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
451int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
452 dscp_t dscp, int oif, struct net_device *dev,
453 struct in_device *idev, u32 *itag);
454
455static inline enum skb_drop_reason
456fib_validate_source_reason(struct sk_buff *skb, __be32 src, __be32 dst,
457 dscp_t dscp, int oif, struct net_device *dev,
458 struct in_device *idev, u32 *itag)
459{
460 int err = fib_validate_source(skb, src, dst, dscp, oif, dev, idev,
461 itag);
462 if (err < 0)
463 return -err;
464 return SKB_NOT_DROPPED_YET;
465}
466
467#ifdef CONFIG_IP_ROUTE_CLASSID
468static inline int fib_num_tclassid_users(struct net *net)
469{
470 return atomic_read(&net->ipv4.fib_num_tclassid_users);
471}
472#else
473static inline int fib_num_tclassid_users(struct net *net)
474{
475 return 0;
476}
477#endif
478int fib_unmerge(struct net *net);
479
480static inline bool nhc_l3mdev_matches_dev(const struct fib_nh_common *nhc,
481const struct net_device *dev)
482{
483 if (nhc->nhc_dev == dev ||
484 l3mdev_master_ifindex_rcu(nhc->nhc_dev) == dev->ifindex)
485 return true;
486
487 return false;
488}
489
490/* Exported by fib_semantics.c */
491int ip_fib_check_default(__be32 gw, struct net_device *dev);
492int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
493int fib_sync_down_addr(struct net_device *dev, __be32 local);
494int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
495void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
496void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
497
498/* Fields used for sysctl_fib_multipath_hash_fields.
499 * Common to IPv4 and IPv6.
500 *
501 * Add new fields at the end. This is user API.
502 */
503#define FIB_MULTIPATH_HASH_FIELD_SRC_IP BIT(0)
504#define FIB_MULTIPATH_HASH_FIELD_DST_IP BIT(1)
505#define FIB_MULTIPATH_HASH_FIELD_IP_PROTO BIT(2)
506#define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL BIT(3)
507#define FIB_MULTIPATH_HASH_FIELD_SRC_PORT BIT(4)
508#define FIB_MULTIPATH_HASH_FIELD_DST_PORT BIT(5)
509#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP BIT(6)
510#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP BIT(7)
511#define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO BIT(8)
512#define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL BIT(9)
513#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT BIT(10)
514#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT BIT(11)
515
516#define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK \
517 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
518 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
519 FIB_MULTIPATH_HASH_FIELD_IP_PROTO | \
520 FIB_MULTIPATH_HASH_FIELD_FLOWLABEL | \
521 FIB_MULTIPATH_HASH_FIELD_SRC_PORT | \
522 FIB_MULTIPATH_HASH_FIELD_DST_PORT)
523
524#define FIB_MULTIPATH_HASH_FIELD_INNER_MASK \
525 (FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP | \
526 FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP | \
527 FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO | \
528 FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL | \
529 FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT | \
530 FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT)
531
532#define FIB_MULTIPATH_HASH_FIELD_ALL_MASK \
533 (FIB_MULTIPATH_HASH_FIELD_OUTER_MASK | \
534 FIB_MULTIPATH_HASH_FIELD_INNER_MASK)
535
536#define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK \
537 (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \
538 FIB_MULTIPATH_HASH_FIELD_DST_IP | \
539 FIB_MULTIPATH_HASH_FIELD_IP_PROTO)
540
541#ifdef CONFIG_IP_ROUTE_MULTIPATH
542int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
543 const struct sk_buff *skb, struct flow_keys *flkeys);
544
545static void
546fib_multipath_hash_construct_key(siphash_key_t *key, u32 mp_seed)
547{
548 u64 mp_seed_64 = mp_seed;
549
550 key->key[0] = (mp_seed_64 << 32) | mp_seed_64;
551 key->key[1] = key->key[0];
552}
553
554static inline u32 fib_multipath_hash_from_keys(const struct net *net,
555 struct flow_keys *keys)
556{
557 siphash_aligned_key_t hash_key;
558 u32 mp_seed;
559
560 mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed).mp_seed;
561 fib_multipath_hash_construct_key(&hash_key, mp_seed);
562
563 return flow_hash_from_keys_seed(keys, &hash_key);
564}
565#else
566static inline u32 fib_multipath_hash_from_keys(const struct net *net,
567 struct flow_keys *keys)
568{
569 return flow_hash_from_keys(keys);
570}
571#endif
572
573int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
574 struct netlink_ext_ack *extack);
575void fib_select_multipath(struct fib_result *res, int hash);
576void fib_select_path(struct net *net, struct fib_result *res,
577 struct flowi4 *fl4, const struct sk_buff *skb);
578
579int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
580 struct fib_config *cfg, int nh_weight,
581 struct netlink_ext_ack *extack);
582void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
583int fib_nh_common_init(struct net *net, struct fib_nh_common *nhc,
584 struct nlattr *fc_encap, u16 fc_encap_type,
585 void *cfg, gfp_t gfp_flags,
586 struct netlink_ext_ack *extack);
587void fib_nh_common_release(struct fib_nh_common *nhc);
588
589/* Exported by fib_trie.c */
590void fib_alias_hw_flags_set(struct net *net, const struct fib_rt_info *fri);
591void fib_trie_init(void);
592struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
593bool fib_lookup_good_nhc(const struct fib_nh_common *nhc, int fib_flags,
594 const struct flowi4 *flp);
595
596static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
597{
598#ifdef CONFIG_IP_ROUTE_CLASSID
599 struct fib_nh_common *nhc = res->nhc;
600#ifdef CONFIG_IP_MULTIPLE_TABLES
601 u32 rtag;
602#endif
603 if (nhc->nhc_family == AF_INET) {
604 struct fib_nh *nh;
605
606 nh = container_of(nhc, struct fib_nh, nh_common);
607 *itag = nh->nh_tclassid << 16;
608 } else {
609 *itag = 0;
610 }
611
612#ifdef CONFIG_IP_MULTIPLE_TABLES
613 rtag = res->tclassid;
614 if (*itag == 0)
615 *itag = (rtag<<16);
616 *itag |= (rtag>>16);
617#endif
618#endif
619}
620
621void fib_flush(struct net *net);
622void free_fib_info(struct fib_info *fi);
623
624static inline void fib_info_hold(struct fib_info *fi)
625{
626 refcount_inc(&fi->fib_clntref);
627}
628
629static inline void fib_info_put(struct fib_info *fi)
630{
631 if (refcount_dec_and_test(&fi->fib_clntref))
632 free_fib_info(fi);
633}
634
635#ifdef CONFIG_PROC_FS
636int __net_init fib_proc_init(struct net *net);
637void __net_exit fib_proc_exit(struct net *net);
638#else
639static inline int fib_proc_init(struct net *net)
640{
641 return 0;
642}
643static inline void fib_proc_exit(struct net *net)
644{
645}
646#endif
647
648u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
649
650int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
651 struct fib_dump_filter *filter,
652 struct netlink_callback *cb);
653
654int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
655 u8 rt_family, unsigned char *flags, bool skip_oif);
656int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
657 int nh_weight, u8 rt_family, u32 nh_tclassid);
658#endif /* _NET_FIB_H */
1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the Forwarding Information Base.
7 *
8 * Authors: A.N.Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15
16#ifndef _NET_IP_FIB_H
17#define _NET_IP_FIB_H
18
19#include <net/flow.h>
20#include <linux/seq_file.h>
21#include <linux/rcupdate.h>
22#include <net/fib_rules.h>
23#include <net/inetpeer.h>
24#include <linux/percpu.h>
25
26struct fib_config {
27 u8 fc_dst_len;
28 u8 fc_tos;
29 u8 fc_protocol;
30 u8 fc_scope;
31 u8 fc_type;
32 /* 3 bytes unused */
33 u32 fc_table;
34 __be32 fc_dst;
35 __be32 fc_gw;
36 int fc_oif;
37 u32 fc_flags;
38 u32 fc_priority;
39 __be32 fc_prefsrc;
40 struct nlattr *fc_mx;
41 struct rtnexthop *fc_mp;
42 int fc_mx_len;
43 int fc_mp_len;
44 u32 fc_flow;
45 u32 fc_nlflags;
46 struct nl_info fc_nlinfo;
47 struct nlattr *fc_encap;
48 u16 fc_encap_type;
49};
50
51struct fib_info;
52struct rtable;
53
54struct fib_nh_exception {
55 struct fib_nh_exception __rcu *fnhe_next;
56 int fnhe_genid;
57 __be32 fnhe_daddr;
58 u32 fnhe_pmtu;
59 __be32 fnhe_gw;
60 unsigned long fnhe_expires;
61 struct rtable __rcu *fnhe_rth_input;
62 struct rtable __rcu *fnhe_rth_output;
63 unsigned long fnhe_stamp;
64 struct rcu_head rcu;
65};
66
67struct fnhe_hash_bucket {
68 struct fib_nh_exception __rcu *chain;
69};
70
71#define FNHE_HASH_SHIFT 11
72#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
73#define FNHE_RECLAIM_DEPTH 5
74
75struct fib_nh {
76 struct net_device *nh_dev;
77 struct hlist_node nh_hash;
78 struct fib_info *nh_parent;
79 unsigned int nh_flags;
80 unsigned char nh_scope;
81#ifdef CONFIG_IP_ROUTE_MULTIPATH
82 int nh_weight;
83 atomic_t nh_upper_bound;
84#endif
85#ifdef CONFIG_IP_ROUTE_CLASSID
86 __u32 nh_tclassid;
87#endif
88 int nh_oif;
89 __be32 nh_gw;
90 __be32 nh_saddr;
91 int nh_saddr_genid;
92 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
93 struct rtable __rcu *nh_rth_input;
94 struct fnhe_hash_bucket __rcu *nh_exceptions;
95 struct lwtunnel_state *nh_lwtstate;
96};
97
98/*
99 * This structure contains data shared by many of routes.
100 */
101
102struct fib_info {
103 struct hlist_node fib_hash;
104 struct hlist_node fib_lhash;
105 struct net *fib_net;
106 int fib_treeref;
107 atomic_t fib_clntref;
108 unsigned int fib_flags;
109 unsigned char fib_dead;
110 unsigned char fib_protocol;
111 unsigned char fib_scope;
112 unsigned char fib_type;
113 __be32 fib_prefsrc;
114 u32 fib_priority;
115 u32 *fib_metrics;
116#define fib_mtu fib_metrics[RTAX_MTU-1]
117#define fib_window fib_metrics[RTAX_WINDOW-1]
118#define fib_rtt fib_metrics[RTAX_RTT-1]
119#define fib_advmss fib_metrics[RTAX_ADVMSS-1]
120 int fib_nhs;
121#ifdef CONFIG_IP_ROUTE_MULTIPATH
122 int fib_weight;
123#endif
124 struct rcu_head rcu;
125 struct fib_nh fib_nh[0];
126#define fib_dev fib_nh[0].nh_dev
127};
128
129
130#ifdef CONFIG_IP_MULTIPLE_TABLES
131struct fib_rule;
132#endif
133
134struct fib_table;
135struct fib_result {
136 unsigned char prefixlen;
137 unsigned char nh_sel;
138 unsigned char type;
139 unsigned char scope;
140 u32 tclassid;
141 struct fib_info *fi;
142 struct fib_table *table;
143 struct hlist_head *fa_head;
144};
145
146struct fib_result_nl {
147 __be32 fl_addr; /* To be looked up*/
148 u32 fl_mark;
149 unsigned char fl_tos;
150 unsigned char fl_scope;
151 unsigned char tb_id_in;
152
153 unsigned char tb_id; /* Results */
154 unsigned char prefixlen;
155 unsigned char nh_sel;
156 unsigned char type;
157 unsigned char scope;
158 int err;
159};
160
161#ifdef CONFIG_IP_ROUTE_MULTIPATH
162#define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
163#else /* CONFIG_IP_ROUTE_MULTIPATH */
164#define FIB_RES_NH(res) ((res).fi->fib_nh[0])
165#endif /* CONFIG_IP_ROUTE_MULTIPATH */
166
167#ifdef CONFIG_IP_MULTIPLE_TABLES
168#define FIB_TABLE_HASHSZ 256
169#else
170#define FIB_TABLE_HASHSZ 2
171#endif
172
173__be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
174
175#define FIB_RES_SADDR(net, res) \
176 ((FIB_RES_NH(res).nh_saddr_genid == \
177 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
178 FIB_RES_NH(res).nh_saddr : \
179 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
180#define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
181#define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
182#define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
183
184#define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
185 FIB_RES_SADDR(net, res))
186
187struct fib_table {
188 struct hlist_node tb_hlist;
189 u32 tb_id;
190 int tb_num_default;
191 struct rcu_head rcu;
192 unsigned long *tb_data;
193 unsigned long __data[0];
194};
195
196int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
197 struct fib_result *res, int fib_flags);
198int fib_table_insert(struct fib_table *, struct fib_config *);
199int fib_table_delete(struct fib_table *, struct fib_config *);
200int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
201 struct netlink_callback *cb);
202int fib_table_flush(struct fib_table *table);
203struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
204void fib_table_flush_external(struct fib_table *table);
205void fib_free_table(struct fib_table *tb);
206
207#ifndef CONFIG_IP_MULTIPLE_TABLES
208
209#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
210#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
211
212static inline struct fib_table *fib_get_table(struct net *net, u32 id)
213{
214 struct hlist_node *tb_hlist;
215 struct hlist_head *ptr;
216
217 ptr = id == RT_TABLE_LOCAL ?
218 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
219 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
220
221 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
222
223 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
224}
225
226static inline struct fib_table *fib_new_table(struct net *net, u32 id)
227{
228 return fib_get_table(net, id);
229}
230
231static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
232 struct fib_result *res, unsigned int flags)
233{
234 struct fib_table *tb;
235 int err = -ENETUNREACH;
236
237 rcu_read_lock();
238
239 tb = fib_get_table(net, RT_TABLE_MAIN);
240 if (tb)
241 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
242
243 if (err == -EAGAIN)
244 err = -ENETUNREACH;
245
246 rcu_read_unlock();
247
248 return err;
249}
250
251#else /* CONFIG_IP_MULTIPLE_TABLES */
252int __net_init fib4_rules_init(struct net *net);
253void __net_exit fib4_rules_exit(struct net *net);
254
255struct fib_table *fib_new_table(struct net *net, u32 id);
256struct fib_table *fib_get_table(struct net *net, u32 id);
257
258int __fib_lookup(struct net *net, struct flowi4 *flp,
259 struct fib_result *res, unsigned int flags);
260
261static inline int fib_lookup(struct net *net, struct flowi4 *flp,
262 struct fib_result *res, unsigned int flags)
263{
264 struct fib_table *tb;
265 int err = -ENETUNREACH;
266
267 flags |= FIB_LOOKUP_NOREF;
268 if (net->ipv4.fib_has_custom_rules)
269 return __fib_lookup(net, flp, res, flags);
270
271 rcu_read_lock();
272
273 res->tclassid = 0;
274
275 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
276 if (tb)
277 err = fib_table_lookup(tb, flp, res, flags);
278
279 if (!err)
280 goto out;
281
282 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
283 if (tb)
284 err = fib_table_lookup(tb, flp, res, flags);
285
286out:
287 if (err == -EAGAIN)
288 err = -ENETUNREACH;
289
290 rcu_read_unlock();
291
292 return err;
293}
294
295#endif /* CONFIG_IP_MULTIPLE_TABLES */
296
297/* Exported by fib_frontend.c */
298extern const struct nla_policy rtm_ipv4_policy[];
299void ip_fib_init(void);
300__be32 fib_compute_spec_dst(struct sk_buff *skb);
301int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
302 u8 tos, int oif, struct net_device *dev,
303 struct in_device *idev, u32 *itag);
304void fib_select_default(const struct flowi4 *flp, struct fib_result *res);
305#ifdef CONFIG_IP_ROUTE_CLASSID
306static inline int fib_num_tclassid_users(struct net *net)
307{
308 return net->ipv4.fib_num_tclassid_users;
309}
310#else
311static inline int fib_num_tclassid_users(struct net *net)
312{
313 return 0;
314}
315#endif
316int fib_unmerge(struct net *net);
317void fib_flush_external(struct net *net);
318
319/* Exported by fib_semantics.c */
320int ip_fib_check_default(__be32 gw, struct net_device *dev);
321int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
322int fib_sync_down_addr(struct net *net, __be32 local);
323int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
324
325extern u32 fib_multipath_secret __read_mostly;
326
327static inline int fib_multipath_hash(__be32 saddr, __be32 daddr)
328{
329 return jhash_2words((__force u32)saddr, (__force u32)daddr,
330 fib_multipath_secret) >> 1;
331}
332
333void fib_select_multipath(struct fib_result *res, int hash);
334void fib_select_path(struct net *net, struct fib_result *res,
335 struct flowi4 *fl4, int mp_hash);
336
337/* Exported by fib_trie.c */
338void fib_trie_init(void);
339struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
340
341static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
342{
343#ifdef CONFIG_IP_ROUTE_CLASSID
344#ifdef CONFIG_IP_MULTIPLE_TABLES
345 u32 rtag;
346#endif
347 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
348#ifdef CONFIG_IP_MULTIPLE_TABLES
349 rtag = res->tclassid;
350 if (*itag == 0)
351 *itag = (rtag<<16);
352 *itag |= (rtag>>16);
353#endif
354#endif
355}
356
357void free_fib_info(struct fib_info *fi);
358
359static inline void fib_info_put(struct fib_info *fi)
360{
361 if (atomic_dec_and_test(&fi->fib_clntref))
362 free_fib_info(fi);
363}
364
365#ifdef CONFIG_PROC_FS
366int __net_init fib_proc_init(struct net *net);
367void __net_exit fib_proc_exit(struct net *net);
368#else
369static inline int fib_proc_init(struct net *net)
370{
371 return 0;
372}
373static inline void fib_proc_exit(struct net *net)
374{
375}
376#endif
377
378#endif /* _NET_FIB_H */