File: /usr/src/linux/include/net/ip_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 <linux/config.h>
20
21 struct kern_rta
22 {
23 void *rta_dst;
24 void *rta_src;
25 int *rta_iif;
26 int *rta_oif;
27 void *rta_gw;
28 u32 *rta_priority;
29 void *rta_prefsrc;
30 struct rtattr *rta_mx;
31 struct rtattr *rta_mp;
32 unsigned char *rta_protoinfo;
33 unsigned char *rta_flow;
34 struct rta_cacheinfo *rta_ci;
35 };
36
37 struct fib_nh
38 {
39 struct net_device *nh_dev;
40 unsigned nh_flags;
41 unsigned char nh_scope;
42 #ifdef CONFIG_IP_ROUTE_MULTIPATH
43 int nh_weight;
44 int nh_power;
45 #endif
46 #ifdef CONFIG_NET_CLS_ROUTE
47 __u32 nh_tclassid;
48 #endif
49 int nh_oif;
50 u32 nh_gw;
51 };
52
53 /*
54 * This structure contains data shared by many of routes.
55 */
56
57 struct fib_info
58 {
59 struct fib_info *fib_next;
60 struct fib_info *fib_prev;
61 int fib_treeref;
62 atomic_t fib_clntref;
63 int fib_dead;
64 unsigned fib_flags;
65 int fib_protocol;
66 u32 fib_prefsrc;
67 u32 fib_priority;
68 unsigned fib_metrics[RTAX_MAX];
69 #define fib_mtu fib_metrics[RTAX_MTU-1]
70 #define fib_window fib_metrics[RTAX_WINDOW-1]
71 #define fib_rtt fib_metrics[RTAX_RTT-1]
72 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
73 int fib_nhs;
74 #ifdef CONFIG_IP_ROUTE_MULTIPATH
75 int fib_power;
76 #endif
77 struct fib_nh fib_nh[0];
78 #define fib_dev fib_nh[0].nh_dev
79 };
80
81
82 #ifdef CONFIG_IP_MULTIPLE_TABLES
83 struct fib_rule;
84 #endif
85
86 struct fib_result
87 {
88 unsigned char prefixlen;
89 unsigned char nh_sel;
90 unsigned char type;
91 unsigned char scope;
92 struct fib_info *fi;
93 #ifdef CONFIG_IP_MULTIPLE_TABLES
94 struct fib_rule *r;
95 #endif
96 };
97
98
99 #ifdef CONFIG_IP_ROUTE_MULTIPATH
100
101 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
102 #define FIB_RES_RESET(res) ((res).nh_sel = 0)
103
104 #else /* CONFIG_IP_ROUTE_MULTIPATH */
105
106 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
107 #define FIB_RES_RESET(res)
108
109 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
110
111 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res))
112 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
113 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
114 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
115
116 struct fib_table
117 {
118 unsigned char tb_id;
119 unsigned tb_stamp;
120 int (*tb_lookup)(struct fib_table *tb, const struct rt_key *key, struct fib_result *res);
121 int (*tb_insert)(struct fib_table *table, struct rtmsg *r,
122 struct kern_rta *rta, struct nlmsghdr *n,
123 struct netlink_skb_parms *req);
124 int (*tb_delete)(struct fib_table *table, struct rtmsg *r,
125 struct kern_rta *rta, struct nlmsghdr *n,
126 struct netlink_skb_parms *req);
127 int (*tb_dump)(struct fib_table *table, struct sk_buff *skb,
128 struct netlink_callback *cb);
129 int (*tb_flush)(struct fib_table *table);
130 int (*tb_get_info)(struct fib_table *table, char *buf,
131 int first, int count);
132 void (*tb_select_default)(struct fib_table *table,
133 const struct rt_key *key, struct fib_result *res);
134
135 unsigned char tb_data[0];
136 };
137
138 #ifndef CONFIG_IP_MULTIPLE_TABLES
139
140 extern struct fib_table *local_table;
141 extern struct fib_table *main_table;
142
143 static inline struct fib_table *fib_get_table(int id)
144 {
145 if (id != RT_TABLE_LOCAL)
146 return main_table;
147 return local_table;
148 }
149
150 static inline struct fib_table *fib_new_table(int id)
151 {
152 return fib_get_table(id);
153 }
154
155 static inline int fib_lookup(const struct rt_key *key, struct fib_result *res)
156 {
157 if (local_table->tb_lookup(local_table, key, res) &&
158 main_table->tb_lookup(main_table, key, res))
159 return -ENETUNREACH;
160 return 0;
161 }
162
163 static inline void fib_select_default(const struct rt_key *key, struct fib_result *res)
164 {
165 if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
166 main_table->tb_select_default(main_table, key, res);
167 }
168
169 #else /* CONFIG_IP_MULTIPLE_TABLES */
170 #define local_table (fib_tables[RT_TABLE_LOCAL])
171 #define main_table (fib_tables[RT_TABLE_MAIN])
172
173 extern struct fib_table * fib_tables[RT_TABLE_MAX+1];
174 extern int fib_lookup(const struct rt_key *key, struct fib_result *res);
175 extern struct fib_table *__fib_new_table(int id);
176 extern void fib_rule_put(struct fib_rule *r);
177
178 static inline struct fib_table *fib_get_table(int id)
179 {
180 if (id == 0)
181 id = RT_TABLE_MAIN;
182
183 return fib_tables[id];
184 }
185
186 static inline struct fib_table *fib_new_table(int id)
187 {
188 if (id == 0)
189 id = RT_TABLE_MAIN;
190
191 return fib_tables[id] ? : __fib_new_table(id);
192 }
193
194 extern void fib_select_default(const struct rt_key *key, struct fib_result *res);
195
196 #endif /* CONFIG_IP_MULTIPLE_TABLES */
197
198 /* Exported by fib_frontend.c */
199 extern void ip_fib_init(void);
200 extern void fib_flush(void);
201 extern int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
202 extern int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
203 extern int inet_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
204 extern int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb);
205 extern int fib_validate_source(u32 src, u32 dst, u8 tos, int oif,
206 struct net_device *dev, u32 *spec_dst, u32 *itag);
207 extern void fib_select_multipath(const struct rt_key *key, struct fib_result *res);
208
209 /* Exported by fib_semantics.c */
210 extern int ip_fib_check_default(u32 gw, struct net_device *dev);
211 extern void fib_release_info(struct fib_info *);
212 extern int fib_semantic_match(int type, struct fib_info *,
213 const struct rt_key *, struct fib_result*);
214 extern struct fib_info *fib_create_info(const struct rtmsg *r, struct kern_rta *rta,
215 const struct nlmsghdr *, int *err);
216 extern int fib_nh_match(struct rtmsg *r, struct nlmsghdr *, struct kern_rta *rta, struct fib_info *fi);
217 extern int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
218 u8 tb_id, u8 type, u8 scope, void *dst, int dst_len, u8 tos,
219 struct fib_info *fi);
220 extern int fib_sync_down(u32 local, struct net_device *dev, int force);
221 extern int fib_sync_up(struct net_device *dev);
222 extern int fib_convert_rtentry(int cmd, struct nlmsghdr *nl, struct rtmsg *rtm,
223 struct kern_rta *rta, struct rtentry *r);
224 extern void fib_node_get_info(int type, int dead, struct fib_info *fi, u32 prefix, u32 mask, char *buffer);
225 extern u32 __fib_res_prefsrc(struct fib_result *res);
226
227 /* Exported by fib_hash.c */
228 extern struct fib_table *fib_hash_init(int id);
229
230 #ifdef CONFIG_IP_MULTIPLE_TABLES
231 /* Exported by fib_rules.c */
232
233 extern int inet_rtm_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
234 extern int inet_rtm_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
235 extern int inet_dump_rules(struct sk_buff *skb, struct netlink_callback *cb);
236 extern u32 fib_rules_map_destination(u32 daddr, struct fib_result *res);
237 #ifdef CONFIG_NET_CLS_ROUTE
238 extern u32 fib_rules_tclass(struct fib_result *res);
239 #endif
240 extern u32 fib_rules_policy(u32 saddr, struct fib_result *res, unsigned *flags);
241 extern void fib_rules_init(void);
242 #endif
243
244 static inline void fib_combine_itag(u32 *itag, struct fib_result *res)
245 {
246 #ifdef CONFIG_NET_CLS_ROUTE
247 #ifdef CONFIG_IP_MULTIPLE_TABLES
248 u32 rtag;
249 #endif
250 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
251 #ifdef CONFIG_IP_MULTIPLE_TABLES
252 rtag = fib_rules_tclass(res);
253 if (*itag == 0)
254 *itag = (rtag<<16);
255 *itag |= (rtag>>16);
256 #endif
257 #endif
258 }
259
260 extern void free_fib_info(struct fib_info *fi);
261
262 static inline void fib_info_put(struct fib_info *fi)
263 {
264 if (atomic_dec_and_test(&fi->fib_clntref))
265 free_fib_info(fi);
266 }
267
268 static inline void fib_res_put(struct fib_result *res)
269 {
270 if (res->fi)
271 fib_info_put(res->fi);
272 #ifdef CONFIG_IP_MULTIPLE_TABLES
273 if (res->r)
274 fib_rule_put(res->r);
275 #endif
276 }
277
278
279 #endif /* _NET_FIB_H */
280