tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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#include <linux/notifier.h>
26
27struct fib_config {
28 u8 fc_dst_len;
29 u8 fc_tos;
30 u8 fc_protocol;
31 u8 fc_scope;
32 u8 fc_type;
33 /* 3 bytes unused */
34 u32 fc_table;
35 __be32 fc_dst;
36 __be32 fc_gw;
37 int fc_oif;
38 u32 fc_flags;
39 u32 fc_priority;
40 __be32 fc_prefsrc;
41 struct nlattr *fc_mx;
42 struct rtnexthop *fc_mp;
43 int fc_mx_len;
44 int fc_mp_len;
45 u32 fc_flow;
46 u32 fc_nlflags;
47 struct nl_info fc_nlinfo;
48 struct nlattr *fc_encap;
49 u16 fc_encap_type;
50};
51
52struct fib_info;
53struct rtable;
54
55struct fib_nh_exception {
56 struct fib_nh_exception __rcu *fnhe_next;
57 int fnhe_genid;
58 __be32 fnhe_daddr;
59 u32 fnhe_pmtu;
60 __be32 fnhe_gw;
61 unsigned long fnhe_expires;
62 struct rtable __rcu *fnhe_rth_input;
63 struct rtable __rcu *fnhe_rth_output;
64 unsigned long fnhe_stamp;
65 struct rcu_head rcu;
66};
67
68struct fnhe_hash_bucket {
69 struct fib_nh_exception __rcu *chain;
70};
71
72#define FNHE_HASH_SHIFT 11
73#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
74#define FNHE_RECLAIM_DEPTH 5
75
76struct fib_nh {
77 struct net_device *nh_dev;
78 struct hlist_node nh_hash;
79 struct fib_info *nh_parent;
80 unsigned int nh_flags;
81 unsigned char nh_scope;
82#ifdef CONFIG_IP_ROUTE_MULTIPATH
83 int nh_weight;
84 atomic_t nh_upper_bound;
85#endif
86#ifdef CONFIG_IP_ROUTE_CLASSID
87 __u32 nh_tclassid;
88#endif
89 int nh_oif;
90 __be32 nh_gw;
91 __be32 nh_saddr;
92 int nh_saddr_genid;
93 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
94 struct rtable __rcu *nh_rth_input;
95 struct fnhe_hash_bucket __rcu *nh_exceptions;
96 struct lwtunnel_state *nh_lwtstate;
97};
98
99/*
100 * This structure contains data shared by many of routes.
101 */
102
103struct fib_info {
104 struct hlist_node fib_hash;
105 struct hlist_node fib_lhash;
106 struct net *fib_net;
107 int fib_treeref;
108 atomic_t fib_clntref;
109 unsigned int fib_flags;
110 unsigned char fib_dead;
111 unsigned char fib_protocol;
112 unsigned char fib_scope;
113 unsigned char fib_type;
114 __be32 fib_prefsrc;
115 u32 fib_tb_id;
116 u32 fib_priority;
117 u32 *fib_metrics;
118#define fib_mtu fib_metrics[RTAX_MTU-1]
119#define fib_window fib_metrics[RTAX_WINDOW-1]
120#define fib_rtt fib_metrics[RTAX_RTT-1]
121#define fib_advmss fib_metrics[RTAX_ADVMSS-1]
122 int fib_nhs;
123#ifdef CONFIG_IP_ROUTE_MULTIPATH
124 int fib_weight;
125#endif
126 unsigned int fib_offload_cnt;
127 struct rcu_head rcu;
128 struct fib_nh fib_nh[0];
129#define fib_dev fib_nh[0].nh_dev
130};
131
132
133#ifdef CONFIG_IP_MULTIPLE_TABLES
134struct fib_rule;
135#endif
136
137struct fib_table;
138struct fib_result {
139 unsigned char prefixlen;
140 unsigned char nh_sel;
141 unsigned char type;
142 unsigned char scope;
143 u32 tclassid;
144 struct fib_info *fi;
145 struct fib_table *table;
146 struct hlist_head *fa_head;
147};
148
149struct fib_result_nl {
150 __be32 fl_addr; /* To be looked up*/
151 u32 fl_mark;
152 unsigned char fl_tos;
153 unsigned char fl_scope;
154 unsigned char tb_id_in;
155
156 unsigned char tb_id; /* Results */
157 unsigned char prefixlen;
158 unsigned char nh_sel;
159 unsigned char type;
160 unsigned char scope;
161 int err;
162};
163
164#ifdef CONFIG_IP_ROUTE_MULTIPATH
165#define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
166#else /* CONFIG_IP_ROUTE_MULTIPATH */
167#define FIB_RES_NH(res) ((res).fi->fib_nh[0])
168#endif /* CONFIG_IP_ROUTE_MULTIPATH */
169
170#ifdef CONFIG_IP_MULTIPLE_TABLES
171#define FIB_TABLE_HASHSZ 256
172#else
173#define FIB_TABLE_HASHSZ 2
174#endif
175
176__be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
177
178static inline void fib_info_offload_inc(struct fib_info *fi)
179{
180 fi->fib_offload_cnt++;
181 fi->fib_flags |= RTNH_F_OFFLOAD;
182}
183
184static inline void fib_info_offload_dec(struct fib_info *fi)
185{
186 if (--fi->fib_offload_cnt == 0)
187 fi->fib_flags &= ~RTNH_F_OFFLOAD;
188}
189
190#define FIB_RES_SADDR(net, res) \
191 ((FIB_RES_NH(res).nh_saddr_genid == \
192 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
193 FIB_RES_NH(res).nh_saddr : \
194 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
195#define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
196#define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
197#define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
198
199#define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
200 FIB_RES_SADDR(net, res))
201
202struct fib_notifier_info {
203 struct net *net;
204};
205
206struct fib_entry_notifier_info {
207 struct fib_notifier_info info; /* must be first */
208 u32 dst;
209 int dst_len;
210 struct fib_info *fi;
211 u8 tos;
212 u8 type;
213 u32 tb_id;
214};
215
216struct fib_nh_notifier_info {
217 struct fib_notifier_info info; /* must be first */
218 struct fib_nh *fib_nh;
219};
220
221enum fib_event_type {
222 FIB_EVENT_ENTRY_REPLACE,
223 FIB_EVENT_ENTRY_APPEND,
224 FIB_EVENT_ENTRY_ADD,
225 FIB_EVENT_ENTRY_DEL,
226 FIB_EVENT_RULE_ADD,
227 FIB_EVENT_RULE_DEL,
228 FIB_EVENT_NH_ADD,
229 FIB_EVENT_NH_DEL,
230};
231
232int register_fib_notifier(struct notifier_block *nb,
233 void (*cb)(struct notifier_block *nb));
234int unregister_fib_notifier(struct notifier_block *nb);
235int call_fib_notifiers(struct net *net, enum fib_event_type event_type,
236 struct fib_notifier_info *info);
237
238struct fib_table {
239 struct hlist_node tb_hlist;
240 u32 tb_id;
241 int tb_num_default;
242 struct rcu_head rcu;
243 unsigned long *tb_data;
244 unsigned long __data[0];
245};
246
247int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
248 struct fib_result *res, int fib_flags);
249int fib_table_insert(struct net *, struct fib_table *, struct fib_config *);
250int fib_table_delete(struct net *, struct fib_table *, struct fib_config *);
251int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
252 struct netlink_callback *cb);
253int fib_table_flush(struct net *net, struct fib_table *table);
254struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
255void fib_table_flush_external(struct fib_table *table);
256void fib_free_table(struct fib_table *tb);
257
258#ifndef CONFIG_IP_MULTIPLE_TABLES
259
260#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
261#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
262
263static inline struct fib_table *fib_get_table(struct net *net, u32 id)
264{
265 struct hlist_node *tb_hlist;
266 struct hlist_head *ptr;
267
268 ptr = id == RT_TABLE_LOCAL ?
269 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
270 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
271
272 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
273
274 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
275}
276
277static inline struct fib_table *fib_new_table(struct net *net, u32 id)
278{
279 return fib_get_table(net, id);
280}
281
282static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
283 struct fib_result *res, unsigned int flags)
284{
285 struct fib_table *tb;
286 int err = -ENETUNREACH;
287
288 rcu_read_lock();
289
290 tb = fib_get_table(net, RT_TABLE_MAIN);
291 if (tb)
292 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
293
294 if (err == -EAGAIN)
295 err = -ENETUNREACH;
296
297 rcu_read_unlock();
298
299 return err;
300}
301
302#else /* CONFIG_IP_MULTIPLE_TABLES */
303int __net_init fib4_rules_init(struct net *net);
304void __net_exit fib4_rules_exit(struct net *net);
305
306struct fib_table *fib_new_table(struct net *net, u32 id);
307struct fib_table *fib_get_table(struct net *net, u32 id);
308
309int __fib_lookup(struct net *net, struct flowi4 *flp,
310 struct fib_result *res, unsigned int flags);
311
312static inline int fib_lookup(struct net *net, struct flowi4 *flp,
313 struct fib_result *res, unsigned int flags)
314{
315 struct fib_table *tb;
316 int err = -ENETUNREACH;
317
318 flags |= FIB_LOOKUP_NOREF;
319 if (net->ipv4.fib_has_custom_rules)
320 return __fib_lookup(net, flp, res, flags);
321
322 rcu_read_lock();
323
324 res->tclassid = 0;
325
326 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
327 if (tb)
328 err = fib_table_lookup(tb, flp, res, flags);
329
330 if (!err)
331 goto out;
332
333 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
334 if (tb)
335 err = fib_table_lookup(tb, flp, res, flags);
336
337out:
338 if (err == -EAGAIN)
339 err = -ENETUNREACH;
340
341 rcu_read_unlock();
342
343 return err;
344}
345
346#endif /* CONFIG_IP_MULTIPLE_TABLES */
347
348/* Exported by fib_frontend.c */
349extern const struct nla_policy rtm_ipv4_policy[];
350void ip_fib_init(void);
351__be32 fib_compute_spec_dst(struct sk_buff *skb);
352int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
353 u8 tos, int oif, struct net_device *dev,
354 struct in_device *idev, u32 *itag);
355#ifdef CONFIG_IP_ROUTE_CLASSID
356static inline int fib_num_tclassid_users(struct net *net)
357{
358 return net->ipv4.fib_num_tclassid_users;
359}
360#else
361static inline int fib_num_tclassid_users(struct net *net)
362{
363 return 0;
364}
365#endif
366int fib_unmerge(struct net *net);
367
368/* Exported by fib_semantics.c */
369int ip_fib_check_default(__be32 gw, struct net_device *dev);
370int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
371int fib_sync_down_addr(struct net_device *dev, __be32 local);
372int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
373
374extern u32 fib_multipath_secret __read_mostly;
375
376static inline int fib_multipath_hash(__be32 saddr, __be32 daddr)
377{
378 return jhash_2words((__force u32)saddr, (__force u32)daddr,
379 fib_multipath_secret) >> 1;
380}
381
382void fib_select_multipath(struct fib_result *res, int hash);
383void fib_select_path(struct net *net, struct fib_result *res,
384 struct flowi4 *fl4, int mp_hash);
385
386/* Exported by fib_trie.c */
387void fib_trie_init(void);
388struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
389
390static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
391{
392#ifdef CONFIG_IP_ROUTE_CLASSID
393#ifdef CONFIG_IP_MULTIPLE_TABLES
394 u32 rtag;
395#endif
396 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
397#ifdef CONFIG_IP_MULTIPLE_TABLES
398 rtag = res->tclassid;
399 if (*itag == 0)
400 *itag = (rtag<<16);
401 *itag |= (rtag>>16);
402#endif
403#endif
404}
405
406void free_fib_info(struct fib_info *fi);
407
408static inline void fib_info_hold(struct fib_info *fi)
409{
410 atomic_inc(&fi->fib_clntref);
411}
412
413static inline void fib_info_put(struct fib_info *fi)
414{
415 if (atomic_dec_and_test(&fi->fib_clntref))
416 free_fib_info(fi);
417}
418
419#ifdef CONFIG_PROC_FS
420int __net_init fib_proc_init(struct net *net);
421void __net_exit fib_proc_exit(struct net *net);
422#else
423static inline int fib_proc_init(struct net *net)
424{
425 return 0;
426}
427static inline void fib_proc_exit(struct net *net)
428{
429}
430#endif
431
432#endif /* _NET_FIB_H */