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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 */
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_notifier.h>
23#include <net/fib_rules.h>
24#include <net/inetpeer.h>
25#include <linux/percpu.h>
26#include <linux/notifier.h>
27#include <linux/refcount.h>
28
29struct fib_config {
30 u8 fc_dst_len;
31 u8 fc_tos;
32 u8 fc_protocol;
33 u8 fc_scope;
34 u8 fc_type;
35 /* 3 bytes unused */
36 u32 fc_table;
37 __be32 fc_dst;
38 __be32 fc_gw;
39 int fc_oif;
40 u32 fc_flags;
41 u32 fc_priority;
42 __be32 fc_prefsrc;
43 struct nlattr *fc_mx;
44 struct rtnexthop *fc_mp;
45 int fc_mx_len;
46 int fc_mp_len;
47 u32 fc_flow;
48 u32 fc_nlflags;
49 struct nl_info fc_nlinfo;
50 struct nlattr *fc_encap;
51 u16 fc_encap_type;
52};
53
54struct fib_info;
55struct rtable;
56
57struct fib_nh_exception {
58 struct fib_nh_exception __rcu *fnhe_next;
59 int fnhe_genid;
60 __be32 fnhe_daddr;
61 u32 fnhe_pmtu;
62 bool fnhe_mtu_locked;
63 __be32 fnhe_gw;
64 unsigned long fnhe_expires;
65 struct rtable __rcu *fnhe_rth_input;
66 struct rtable __rcu *fnhe_rth_output;
67 unsigned long fnhe_stamp;
68 struct rcu_head rcu;
69};
70
71struct fnhe_hash_bucket {
72 struct fib_nh_exception __rcu *chain;
73};
74
75#define FNHE_HASH_SHIFT 11
76#define FNHE_HASH_SIZE (1 << FNHE_HASH_SHIFT)
77#define FNHE_RECLAIM_DEPTH 5
78
79struct fib_nh {
80 struct net_device *nh_dev;
81 struct hlist_node nh_hash;
82 struct fib_info *nh_parent;
83 unsigned int nh_flags;
84 unsigned char nh_scope;
85#ifdef CONFIG_IP_ROUTE_MULTIPATH
86 int nh_weight;
87 atomic_t nh_upper_bound;
88#endif
89#ifdef CONFIG_IP_ROUTE_CLASSID
90 __u32 nh_tclassid;
91#endif
92 int nh_oif;
93 __be32 nh_gw;
94 __be32 nh_saddr;
95 int nh_saddr_genid;
96 struct rtable __rcu * __percpu *nh_pcpu_rth_output;
97 struct rtable __rcu *nh_rth_input;
98 struct fnhe_hash_bucket __rcu *nh_exceptions;
99 struct lwtunnel_state *nh_lwtstate;
100};
101
102/*
103 * This structure contains data shared by many of routes.
104 */
105
106struct fib_info {
107 struct hlist_node fib_hash;
108 struct hlist_node fib_lhash;
109 struct net *fib_net;
110 int fib_treeref;
111 refcount_t fib_clntref;
112 unsigned int fib_flags;
113 unsigned char fib_dead;
114 unsigned char fib_protocol;
115 unsigned char fib_scope;
116 unsigned char fib_type;
117 __be32 fib_prefsrc;
118 u32 fib_tb_id;
119 u32 fib_priority;
120 struct dst_metrics *fib_metrics;
121#define fib_mtu fib_metrics->metrics[RTAX_MTU-1]
122#define fib_window fib_metrics->metrics[RTAX_WINDOW-1]
123#define fib_rtt fib_metrics->metrics[RTAX_RTT-1]
124#define fib_advmss fib_metrics->metrics[RTAX_ADVMSS-1]
125 int fib_nhs;
126 struct rcu_head rcu;
127 struct fib_nh fib_nh[0];
128#define fib_dev fib_nh[0].nh_dev
129};
130
131
132#ifdef CONFIG_IP_MULTIPLE_TABLES
133struct fib_rule;
134#endif
135
136struct fib_table;
137struct fib_result {
138 __be32 prefix;
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
178#define FIB_RES_SADDR(net, res) \
179 ((FIB_RES_NH(res).nh_saddr_genid == \
180 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
181 FIB_RES_NH(res).nh_saddr : \
182 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
183#define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
184#define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
185#define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
186
187#define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
188 FIB_RES_SADDR(net, res))
189
190struct fib_entry_notifier_info {
191 struct fib_notifier_info info; /* must be first */
192 u32 dst;
193 int dst_len;
194 struct fib_info *fi;
195 u8 tos;
196 u8 type;
197 u32 tb_id;
198};
199
200struct fib_nh_notifier_info {
201 struct fib_notifier_info info; /* must be first */
202 struct fib_nh *fib_nh;
203};
204
205int call_fib4_notifier(struct notifier_block *nb, struct net *net,
206 enum fib_event_type event_type,
207 struct fib_notifier_info *info);
208int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
209 struct fib_notifier_info *info);
210
211int __net_init fib4_notifier_init(struct net *net);
212void __net_exit fib4_notifier_exit(struct net *net);
213
214void fib_notify(struct net *net, struct notifier_block *nb);
215
216struct fib_table {
217 struct hlist_node tb_hlist;
218 u32 tb_id;
219 int tb_num_default;
220 struct rcu_head rcu;
221 unsigned long *tb_data;
222 unsigned long __data[0];
223};
224
225int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
226 struct fib_result *res, int fib_flags);
227int fib_table_insert(struct net *, struct fib_table *, struct fib_config *,
228 struct netlink_ext_ack *extack);
229int fib_table_delete(struct net *, struct fib_table *, struct fib_config *,
230 struct netlink_ext_ack *extack);
231int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
232 struct netlink_callback *cb);
233int fib_table_flush(struct net *net, struct fib_table *table);
234struct fib_table *fib_trie_unmerge(struct fib_table *main_tb);
235void fib_table_flush_external(struct fib_table *table);
236void fib_free_table(struct fib_table *tb);
237
238#ifndef CONFIG_IP_MULTIPLE_TABLES
239
240#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
241#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
242
243static inline struct fib_table *fib_get_table(struct net *net, u32 id)
244{
245 struct hlist_node *tb_hlist;
246 struct hlist_head *ptr;
247
248 ptr = id == RT_TABLE_LOCAL ?
249 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
250 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
251
252 tb_hlist = rcu_dereference_rtnl(hlist_first_rcu(ptr));
253
254 return hlist_entry(tb_hlist, struct fib_table, tb_hlist);
255}
256
257static inline struct fib_table *fib_new_table(struct net *net, u32 id)
258{
259 return fib_get_table(net, id);
260}
261
262static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
263 struct fib_result *res, unsigned int flags)
264{
265 struct fib_table *tb;
266 int err = -ENETUNREACH;
267
268 rcu_read_lock();
269
270 tb = fib_get_table(net, RT_TABLE_MAIN);
271 if (tb)
272 err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF);
273
274 if (err == -EAGAIN)
275 err = -ENETUNREACH;
276
277 rcu_read_unlock();
278
279 return err;
280}
281
282static inline bool fib4_rule_default(const struct fib_rule *rule)
283{
284 return true;
285}
286
287static inline int fib4_rules_dump(struct net *net, struct notifier_block *nb)
288{
289 return 0;
290}
291
292static inline unsigned int fib4_rules_seq_read(struct net *net)
293{
294 return 0;
295}
296
297static inline bool fib4_rules_early_flow_dissect(struct net *net,
298 struct sk_buff *skb,
299 struct flowi4 *fl4,
300 struct flow_keys *flkeys)
301{
302 return false;
303}
304#else /* CONFIG_IP_MULTIPLE_TABLES */
305int __net_init fib4_rules_init(struct net *net);
306void __net_exit fib4_rules_exit(struct net *net);
307
308struct fib_table *fib_new_table(struct net *net, u32 id);
309struct fib_table *fib_get_table(struct net *net, u32 id);
310
311int __fib_lookup(struct net *net, struct flowi4 *flp,
312 struct fib_result *res, unsigned int flags);
313
314static inline int fib_lookup(struct net *net, struct flowi4 *flp,
315 struct fib_result *res, unsigned int flags)
316{
317 struct fib_table *tb;
318 int err = -ENETUNREACH;
319
320 flags |= FIB_LOOKUP_NOREF;
321 if (net->ipv4.fib_has_custom_rules)
322 return __fib_lookup(net, flp, res, flags);
323
324 rcu_read_lock();
325
326 res->tclassid = 0;
327
328 tb = rcu_dereference_rtnl(net->ipv4.fib_main);
329 if (tb)
330 err = fib_table_lookup(tb, flp, res, flags);
331
332 if (!err)
333 goto out;
334
335 tb = rcu_dereference_rtnl(net->ipv4.fib_default);
336 if (tb)
337 err = fib_table_lookup(tb, flp, res, flags);
338
339out:
340 if (err == -EAGAIN)
341 err = -ENETUNREACH;
342
343 rcu_read_unlock();
344
345 return err;
346}
347
348bool fib4_rule_default(const struct fib_rule *rule);
349int fib4_rules_dump(struct net *net, struct notifier_block *nb);
350unsigned int fib4_rules_seq_read(struct net *net);
351
352static inline bool fib4_rules_early_flow_dissect(struct net *net,
353 struct sk_buff *skb,
354 struct flowi4 *fl4,
355 struct flow_keys *flkeys)
356{
357 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
358
359 if (!net->ipv4.fib_rules_require_fldissect)
360 return false;
361
362 skb_flow_dissect_flow_keys(skb, flkeys, flag);
363 fl4->fl4_sport = flkeys->ports.src;
364 fl4->fl4_dport = flkeys->ports.dst;
365 fl4->flowi4_proto = flkeys->basic.ip_proto;
366
367 return true;
368}
369
370#endif /* CONFIG_IP_MULTIPLE_TABLES */
371
372/* Exported by fib_frontend.c */
373extern const struct nla_policy rtm_ipv4_policy[];
374void ip_fib_init(void);
375__be32 fib_compute_spec_dst(struct sk_buff *skb);
376int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
377 u8 tos, int oif, struct net_device *dev,
378 struct in_device *idev, u32 *itag);
379#ifdef CONFIG_IP_ROUTE_CLASSID
380static inline int fib_num_tclassid_users(struct net *net)
381{
382 return net->ipv4.fib_num_tclassid_users;
383}
384#else
385static inline int fib_num_tclassid_users(struct net *net)
386{
387 return 0;
388}
389#endif
390int fib_unmerge(struct net *net);
391
392/* Exported by fib_semantics.c */
393int ip_fib_check_default(__be32 gw, struct net_device *dev);
394int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
395int fib_sync_down_addr(struct net_device *dev, __be32 local);
396int fib_sync_up(struct net_device *dev, unsigned int nh_flags);
397
398#ifdef CONFIG_IP_ROUTE_MULTIPATH
399int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
400 const struct sk_buff *skb, struct flow_keys *flkeys);
401#endif
402void fib_select_multipath(struct fib_result *res, int hash);
403void fib_select_path(struct net *net, struct fib_result *res,
404 struct flowi4 *fl4, const struct sk_buff *skb);
405
406/* Exported by fib_trie.c */
407void fib_trie_init(void);
408struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
409
410static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
411{
412#ifdef CONFIG_IP_ROUTE_CLASSID
413#ifdef CONFIG_IP_MULTIPLE_TABLES
414 u32 rtag;
415#endif
416 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
417#ifdef CONFIG_IP_MULTIPLE_TABLES
418 rtag = res->tclassid;
419 if (*itag == 0)
420 *itag = (rtag<<16);
421 *itag |= (rtag>>16);
422#endif
423#endif
424}
425
426void free_fib_info(struct fib_info *fi);
427
428static inline void fib_info_hold(struct fib_info *fi)
429{
430 refcount_inc(&fi->fib_clntref);
431}
432
433static inline void fib_info_put(struct fib_info *fi)
434{
435 if (refcount_dec_and_test(&fi->fib_clntref))
436 free_fib_info(fi);
437}
438
439#ifdef CONFIG_PROC_FS
440int __net_init fib_proc_init(struct net *net);
441void __net_exit fib_proc_exit(struct net *net);
442#else
443static inline int fib_proc_init(struct net *net)
444{
445 return 0;
446}
447static inline void fib_proc_exit(struct net *net)
448{
449}
450#endif
451
452#endif /* _NET_FIB_H */