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Linux kernel mirror (for testing)
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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/inetpeer.h>
21#include <linux/percpu.h>
22#include <linux/notifier.h>
23#include <linux/refcount.h>
24
25struct fib_config {
26 u8 fc_dst_len;
27 u8 fc_tos;
28 u8 fc_protocol;
29 u8 fc_scope;
30 u8 fc_type;
31 u8 fc_gw_family;
32 /* 2 bytes unused */
33 u32 fc_table;
34 __be32 fc_dst;
35 union {
36 __be32 fc_gw4;
37 struct in6_addr fc_gw6;
38 };
39 int fc_oif;
40 u32 fc_flags;
41 u32 fc_priority;
42 __be32 fc_prefsrc;
43 u32 fc_nh_id;
44 struct nlattr *fc_mx;
45 struct rtnexthop *fc_mp;
46 int fc_mx_len;
47 int fc_mp_len;
48 u32 fc_flow;
49 u32 fc_nlflags;
50 struct nl_info fc_nlinfo;
51 struct nlattr *fc_encap;
52 u16 fc_encap_type;
53};
54
55struct fib_info;
56struct rtable;
57
58struct fib_nh_exception {
59 struct fib_nh_exception __rcu *fnhe_next;
60 int fnhe_genid;
61 __be32 fnhe_daddr;
62 u32 fnhe_pmtu;
63 bool fnhe_mtu_locked;
64 __be32 fnhe_gw;
65 unsigned long fnhe_expires;
66 struct rtable __rcu *fnhe_rth_input;
67 struct rtable __rcu *fnhe_rth_output;
68 unsigned long fnhe_stamp;
69 struct rcu_head rcu;
70};
71
72struct fnhe_hash_bucket {
73 struct fib_nh_exception __rcu *chain;
74};
75
76#define FNHE_HASH_SHIFT 11
77#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
78#define FNHE_RECLAIM_DEPTH 5
79
80struct fib_nh_common {
81 struct net_device *nhc_dev;
82 int nhc_oif;
83 unsigned char nhc_scope;
84 u8 nhc_family;
85 u8 nhc_gw_family;
86 unsigned char nhc_flags;
87 struct lwtunnel_state *nhc_lwtstate;
88
89 union {
90 __be32 ipv4;
91 struct in6_addr ipv6;
92 } nhc_gw;
93
94 int nhc_weight;
95 atomic_t nhc_upper_bound;
96
97 /* v4 specific, but allows fib6_nh with v4 routes */
98 struct rtable __rcu * __percpu *nhc_pcpu_rth_output;
99 struct rtable __rcu *nhc_rth_input;
100 struct fnhe_hash_bucket __rcu *nhc_exceptions;
101};
102
103struct fib_nh {
104 struct fib_nh_common nh_common;
105 struct hlist_node nh_hash;
106 struct fib_info *nh_parent;
107#ifdef CONFIG_IP_ROUTE_CLASSID
108 __u32 nh_tclassid;
109#endif
110 __be32 nh_saddr;
111 int nh_saddr_genid;
112#define fib_nh_family nh_common.nhc_family
113#define fib_nh_dev nh_common.nhc_dev
114#define fib_nh_oif nh_common.nhc_oif
115#define fib_nh_flags nh_common.nhc_flags
116#define fib_nh_lws nh_common.nhc_lwtstate
117#define fib_nh_scope nh_common.nhc_scope
118#define fib_nh_gw_family nh_common.nhc_gw_family
119#define fib_nh_gw4 nh_common.nhc_gw.ipv4
120#define fib_nh_gw6 nh_common.nhc_gw.ipv6
121#define fib_nh_weight nh_common.nhc_weight
122#define fib_nh_upper_bound nh_common.nhc_upper_bound
123};
124
125/*
126 * This structure contains data shared by many of routes.
127 */
128
129struct nexthop;
130
131struct fib_info {
132 struct hlist_node fib_hash;
133 struct hlist_node fib_lhash;
134 struct list_head nh_list;
135 struct net *fib_net;
136 int fib_treeref;
137 refcount_t fib_clntref;
138 unsigned int fib_flags;
139 unsigned char fib_dead;
140 unsigned char fib_protocol;
141 unsigned char fib_scope;
142 unsigned char fib_type;
143 __be32 fib_prefsrc;
144 u32 fib_tb_id;
145 u32 fib_priority;
146 struct dst_metrics *fib_metrics;
147#define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
148#define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
149#define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
150#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
151 int fib_nhs;
152 bool fib_nh_is_v6;
153 bool nh_updated;
154 struct nexthop *nh;
155 struct rcu_head rcu;
156 struct fib_nh fib_nh[0];
157};
158
159
160#ifdef CONFIG_IP_MULTIPLE_TABLES
161struct fib_rule;
162#endif
163
164struct fib_table;
165struct fib_result {
166 __be32 prefix;
167 unsigned char prefixlen;
168 unsigned char nh_sel;
169 unsigned char type;
170 unsigned char scope;
171 u32 tclassid;
172 struct fib_nh_common *nhc;
173 struct fib_info *fi;
174 struct fib_table *table;
175 struct hlist_head *fa_head;
176};
177
178struct fib_result_nl {
179 __be32 fl_addr; /* To be looked up*/
180 u32 fl_mark;
181 unsigned char fl_tos;
182 unsigned char fl_scope;
183 unsigned char tb_id_in;
184
185 unsigned char tb_id; /* Results */
186 unsigned char prefixlen;
187 unsigned char nh_sel;
188 unsigned char type;
189 unsigned char scope;
190 int err;
191};
192
193#ifdef CONFIG_IP_MULTIPLE_TABLES
194#define FIB_TABLE_HASHSZ 256
195#else
196#define FIB_TABLE_HASHSZ 2
197#endif
198
199__be32 fib_info_update_nhc_saddr(struct net *net, struct fib_nh_common *nhc,
200 unsigned char scope);
201__be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
202
203#define FIB_RES_NHC(res) ((res).nhc)
204#define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
205#define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
206
207struct fib_entry_notifier_info {
208 struct fib_notifier_info info; /* must be first */
209 u32 dst;
210 int dst_len;
211 struct fib_info *fi;
212 u8 tos;
213 u8 type;
214 u32 tb_id;
215};
216
217struct fib_nh_notifier_info {
218 struct fib_notifier_info info; /* must be first */
219 struct fib_nh *fib_nh;
220};
221
222int call_fib4_notifier(struct notifier_block *nb,
223 enum fib_event_type event_type,
224 struct fib_notifier_info *info);
225int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
226 struct fib_notifier_info *info);
227
228int __net_init fib4_notifier_init(struct net *net);
229void __net_exit fib4_notifier_exit(struct net *net);
230
231void fib_info_notify_update(struct net *net, struct nl_info *info);
232int fib_notify(struct net *net, struct notifier_block *nb,
233 struct netlink_ext_ack *extack);
234
235struct fib_table {
236 struct hlist_node tb_hlist;
237 u32 tb_id;
238 int tb_num_default;
239 struct rcu_head rcu;
240 unsigned long *tb_data;
241 unsigned long __data[0];
242};
243
244struct fib_dump_filter {
245 u32 table_id;
246 /* filter_set is an optimization that an entry is set */
247 bool filter_set;
248 bool dump_all_families;
249 bool dump_routes;
250 bool dump_exceptions;
251 unsigned char protocol;
252 unsigned char rt_type;
253 unsigned int flags;
254 struct net_device *dev;
255};
256
257int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
258 struct fib_result *res, int fib_flags);
259int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
260 struct netlink_ext_ack *extack);
261int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
262 struct netlink_ext_ack *extack);
263int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
264 struct netlink_callback *cb, struct fib_dump_filter *filter);
265int fib_table_flush(struct net *net, struct fib_table *table, bool flush_all);
266struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
267void fib_table_flush_external(struct fib_table *table);
268void fib_free_table(struct fib_table *tb);
269
270#ifndef CONFIG_IP_MULTIPLE_TABLES
271
272#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
273#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
274
275static inline struct fib_table *fib_get_table(struct net *net, u32 id)
276{
277 struct hlist_node *tb_hlist;
278 struct hlist_head *ptr;
279
280 ptr = id == RT_TABLE_LOCAL ?
281 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
282 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
283
284 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
285
286 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
287}
288
289static inline struct fib_table *fib_new_table(struct net *net, u32 id)
290{
291 return fib_get_table(net, id);
292}
293
294static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
295 struct fib_result *res, unsigned int flags)
296{
297 struct fib_table *tb;
298 int err = -ENETUNREACH;
299
300 rcu_read_lock();
301
302 tb = fib_get_table(net, RT_TABLE_MAIN);
303 if (tb)
304 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
305
306 if (err == -EAGAIN)
307 err = -ENETUNREACH;
308
309 rcu_read_unlock();
310
311 return err;
312}
313
314static inline bool fib4_has_custom_rules(const struct net *net)
315{
316 return false;
317}
318
319static inline bool fib4_rule_default(const struct fib_rule *rule)
320{
321 return true;
322}
323
324static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb,
325 struct netlink_ext_ack *extack)
326{
327 return 0;
328}
329
330static inline unsigned int fib4_rules_seq_read(struct net *net)
331{
332 return 0;
333}
334
335static inline bool fib4_rules_early_flow_dissect(struct net *net,
336 struct sk_buff *skb,
337 struct flowi4 *fl4,
338 struct flow_keys *flkeys)
339{
340 return false;
341}
342#else /* CONFIG_IP_MULTIPLE_TABLES */
343int __net_init fib4_rules_init(struct net *net);
344void __net_exit fib4_rules_exit(struct net *net);
345
346struct fib_table *fib_new_table(struct net *net, u32 id);
347struct fib_table *fib_get_table(struct net *net, u32 id);
348
349int __fib_lookup(struct net *net, struct flowi4 *flp,
350 struct fib_result *res, unsigned int flags);
351
352static inline int fib_lookup(struct net *net, struct flowi4 *flp,
353 struct fib_result *res, unsigned int flags)
354{
355 struct fib_table *tb;
356 int err = -ENETUNREACH;
357
358 flags |= FIB_LOOKUP_NOREF;
359 if (net->ipv4.fib_has_custom_rules)
360 return __fib_lookup(net, flp, res, flags);
361
362 rcu_read_lock();
363
364 res->tclassid = 0;
365
366 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
367 if (tb)
368 err = fib_table_lookup(tb, flp, res, flags);
369
370 if (!err)
371 goto out;
372
373 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
374 if (tb)
375 err = fib_table_lookup(tb, flp, res, flags);
376
377out:
378 if (err == -EAGAIN)
379 err = -ENETUNREACH;
380
381 rcu_read_unlock();
382
383 return err;
384}
385
386static inline bool fib4_has_custom_rules(const struct net *net)
387{
388 return net->ipv4.fib_has_custom_rules;
389}
390
391bool fib4_rule_default(const struct fib_rule *rule);
392int fib4_rules_dump(struct net *net, struct notifier_block *nb,
393 struct netlink_ext_ack *extack);
394unsigned int fib4_rules_seq_read(struct net *net);
395
396static inline bool fib4_rules_early_flow_dissect(struct net *net,
397 struct sk_buff *skb,
398 struct flowi4 *fl4,
399 struct flow_keys *flkeys)
400{
401 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
402
403 if (!net->ipv4.fib_rules_require_fldissect)
404 return false;
405
406 skb_flow_dissect_flow_keys(skb, flkeys, flag);
407 fl4->fl4_sport = flkeys->ports.src;
408 fl4->fl4_dport = flkeys->ports.dst;
409 fl4->flowi4_proto = flkeys->basic.ip_proto;
410
411 return true;
412}
413
414#endif /* CONFIG_IP_MULTIPLE_TABLES */
415
416/* Exported by fib_frontend.c */
417extern const struct nla_policy rtm_ipv4_policy[];
418void ip_fib_init(void);
419int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla,
420 struct netlink_ext_ack *extack);
421__be32 fib_compute_spec_dst(struct sk_buff *skb);
422bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
423int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
424 u8 tos, int oif, struct net_device *dev,
425 struct in_device *idev, u32 *itag);
426#ifdef CONFIG_IP_ROUTE_CLASSID
427static inline int fib_num_tclassid_users(struct net *net)
428{
429 return net->ipv4.fib_num_tclassid_users;
430}
431#else
432static inline int fib_num_tclassid_users(struct net *net)
433{
434 return 0;
435}
436#endif
437int fib_unmerge(struct net *net);
438
439/* Exported by fib_semantics.c */
440int ip_fib_check_default(__be32 gw, struct net_device *dev);
441int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
442int fib_sync_down_addr(struct net_device *dev, __be32 local);
443int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
444void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
445void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
446
447#ifdef CONFIG_IP_ROUTE_MULTIPATH
448int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
449 const struct sk_buff *skb, struct flow_keys *flkeys);
450#endif
451int fib_check_nh(struct net *net, struct fib_nh *nh, u32 table, u8 scope,
452 struct netlink_ext_ack *extack);
453void fib_select_multipath(struct fib_result *res, int hash);
454void fib_select_path(struct net *net, struct fib_result *res,
455 struct flowi4 *fl4, const struct sk_buff *skb);
456
457int fib_nh_init(struct net *net, struct fib_nh *fib_nh,
458 struct fib_config *cfg, int nh_weight,
459 struct netlink_ext_ack *extack);
460void fib_nh_release(struct net *net, struct fib_nh *fib_nh);
461int fib_nh_common_init(struct fib_nh_common *nhc, struct nlattr *fc_encap,
462 u16 fc_encap_type, void *cfg, gfp_t gfp_flags,
463 struct netlink_ext_ack *extack);
464void fib_nh_common_release(struct fib_nh_common *nhc);
465
466/* Exported by fib_trie.c */
467void fib_trie_init(void);
468struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
469
470static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
471{
472#ifdef CONFIG_IP_ROUTE_CLASSID
473 struct fib_nh_common *nhc = res->nhc;
474#ifdef CONFIG_IP_MULTIPLE_TABLES
475 u32 rtag;
476#endif
477 if (nhc->nhc_family == AF_INET) {
478 struct fib_nh *nh;
479
480 nh = container_of(nhc, struct fib_nh, nh_common);
481 *itag = nh->nh_tclassid << 16;
482 } else {
483 *itag = 0;
484 }
485
486#ifdef CONFIG_IP_MULTIPLE_TABLES
487 rtag = res->tclassid;
488 if (*itag == 0)
489 *itag = (rtag<<16);
490 *itag |= (rtag>>16);
491#endif
492#endif
493}
494
495void fib_flush(struct net *net);
496void free_fib_info(struct fib_info *fi);
497
498static inline void fib_info_hold(struct fib_info *fi)
499{
500 refcount_inc(&fi->fib_clntref);
501}
502
503static inline void fib_info_put(struct fib_info *fi)
504{
505 if (refcount_dec_and_test(&fi->fib_clntref))
506 free_fib_info(fi);
507}
508
509#ifdef CONFIG_PROC_FS
510int __net_init fib_proc_init(struct net *net);
511void __net_exit fib_proc_exit(struct net *net);
512#else
513static inline int fib_proc_init(struct net *net)
514{
515 return 0;
516}
517static inline void fib_proc_exit(struct net *net)
518{
519}
520#endif
521
522u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr);
523
524int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
525 struct fib_dump_filter *filter,
526 struct netlink_callback *cb);
527
528int fib_nexthop_info(struct sk_buff *skb, const struct fib_nh_common *nh,
529 u8 rt_family, unsigned char *flags, bool skip_oif);
530int fib_add_nexthop(struct sk_buff *skb, const struct fib_nh_common *nh,
531 int nh_weight, u8 rt_family);
532#endif /* _NET_FIB_H */