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 <net/fib_rules.h>
22
23 struct fib_config {
24 u8 fc_dst_len;
25 u8 fc_tos;
26 u8 fc_protocol;
27 u8 fc_scope;
28 u8 fc_type;
29 /* 3 bytes unused */
30 u32 fc_table;
31 __be32 fc_dst;
32 __be32 fc_gw;
33 int fc_oif;
34 u32 fc_flags;
35 u32 fc_priority;
36 __be32 fc_prefsrc;
37 struct nlattr *fc_mx;
38 struct rtnexthop *fc_mp;
39 int fc_mx_len;
40 int fc_mp_len;
41 u32 fc_flow;
42 u32 fc_nlflags;
43 struct nl_info fc_nlinfo;
44 };
45
46 struct fib_info;
47
48 struct fib_nh {
49 struct net_device *nh_dev;
50 struct hlist_node nh_hash;
51 struct fib_info *nh_parent;
52 unsigned nh_flags;
53 unsigned char nh_scope;
54 #ifdef CONFIG_IP_ROUTE_MULTIPATH
55 int nh_weight;
56 int nh_power;
57 #endif
58 #ifdef CONFIG_IP_ROUTE_CLASSID
59 __u32 nh_tclassid;
60 #endif
61 int nh_oif;
62 __be32 nh_gw;
63 __be32 nh_saddr;
64 int nh_saddr_genid;
65 };
66
67 /*
68 * This structure contains data shared by many of routes.
69 */
70
71 struct fib_info {
72 struct hlist_node fib_hash;
73 struct hlist_node fib_lhash;
74 struct net *fib_net;
75 int fib_treeref;
76 atomic_t fib_clntref;
77 unsigned fib_flags;
78 unsigned char fib_dead;
79 unsigned char fib_protocol;
80 unsigned char fib_scope;
81 __be32 fib_prefsrc;
82 u32 fib_priority;
83 u32 *fib_metrics;
84 #define fib_mtu fib_metrics[RTAX_MTU-1]
85 #define fib_window fib_metrics[RTAX_WINDOW-1]
86 #define fib_rtt fib_metrics[RTAX_RTT-1]
87 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
88 int fib_nhs;
89 #ifdef CONFIG_IP_ROUTE_MULTIPATH
90 int fib_power;
91 #endif
92 struct rcu_head rcu;
93 struct fib_nh fib_nh[0];
94 #define fib_dev fib_nh[0].nh_dev
95 };
96
97
98 #ifdef CONFIG_IP_MULTIPLE_TABLES
99 struct fib_rule;
100 #endif
101
102 struct fib_table;
103 struct fib_result {
104 unsigned char prefixlen;
105 unsigned char nh_sel;
106 unsigned char type;
107 unsigned char scope;
108 struct fib_info *fi;
109 struct fib_table *table;
110 struct list_head *fa_head;
111 #ifdef CONFIG_IP_MULTIPLE_TABLES
112 struct fib_rule *r;
113 #endif
114 };
115
116 struct fib_result_nl {
117 __be32 fl_addr; /* To be looked up*/
118 u32 fl_mark;
119 unsigned char fl_tos;
120 unsigned char fl_scope;
121 unsigned char tb_id_in;
122
123 unsigned char tb_id; /* Results */
124 unsigned char prefixlen;
125 unsigned char nh_sel;
126 unsigned char type;
127 unsigned char scope;
128 int err;
129 };
130
131 #ifdef CONFIG_IP_ROUTE_MULTIPATH
132 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
133 #else /* CONFIG_IP_ROUTE_MULTIPATH */
134 #define FIB_RES_NH(res) ((res).fi->fib_nh[0])
135 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
136
137 #ifdef CONFIG_IP_MULTIPLE_TABLES
138 #define FIB_TABLE_HASHSZ 256
139 #else
140 #define FIB_TABLE_HASHSZ 2
141 #endif
142
143 extern __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
144
145 #define FIB_RES_SADDR(net, res) \
146 ((FIB_RES_NH(res).nh_saddr_genid == \
147 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
148 FIB_RES_NH(res).nh_saddr : \
149 fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
150 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw)
151 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev)
152 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif)
153
154 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
155 FIB_RES_SADDR(net, res))
156
157 struct fib_table {
158 struct hlist_node tb_hlist;
159 u32 tb_id;
160 int tb_default;
161 int tb_num_default;
162 unsigned long tb_data[0];
163 };
164
165 extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
166 struct fib_result *res, int fib_flags);
167 extern int fib_table_insert(struct fib_table *, struct fib_config *);
168 extern int fib_table_delete(struct fib_table *, struct fib_config *);
169 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
170 struct netlink_callback *cb);
171 extern int fib_table_flush(struct fib_table *table);
172 extern void fib_free_table(struct fib_table *tb);
173
174
175
176 #ifndef CONFIG_IP_MULTIPLE_TABLES
177
178 #define TABLE_LOCAL_INDEX 0
179 #define TABLE_MAIN_INDEX 1
180
fib_get_table(struct net * net,u32 id)181 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
182 {
183 struct hlist_head *ptr;
184
185 ptr = id == RT_TABLE_LOCAL ?
186 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
187 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
188 return hlist_entry(ptr->first, struct fib_table, tb_hlist);
189 }
190
fib_new_table(struct net * net,u32 id)191 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
192 {
193 return fib_get_table(net, id);
194 }
195
fib_lookup(struct net * net,const struct flowi4 * flp,struct fib_result * res)196 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
197 struct fib_result *res)
198 {
199 struct fib_table *table;
200
201 table = fib_get_table(net, RT_TABLE_LOCAL);
202 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
203 return 0;
204
205 table = fib_get_table(net, RT_TABLE_MAIN);
206 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
207 return 0;
208 return -ENETUNREACH;
209 }
210
211 #else /* CONFIG_IP_MULTIPLE_TABLES */
212 extern int __net_init fib4_rules_init(struct net *net);
213 extern void __net_exit fib4_rules_exit(struct net *net);
214
215 #ifdef CONFIG_IP_ROUTE_CLASSID
216 extern u32 fib_rules_tclass(const struct fib_result *res);
217 #endif
218
219 extern int fib_lookup(struct net *n, struct flowi4 *flp, struct fib_result *res);
220
221 extern struct fib_table *fib_new_table(struct net *net, u32 id);
222 extern struct fib_table *fib_get_table(struct net *net, u32 id);
223
224 #endif /* CONFIG_IP_MULTIPLE_TABLES */
225
226 /* Exported by fib_frontend.c */
227 extern const struct nla_policy rtm_ipv4_policy[];
228 extern void ip_fib_init(void);
229 extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
230 u8 tos, int oif, struct net_device *dev,
231 __be32 *spec_dst, u32 *itag);
232 extern void fib_select_default(struct fib_result *res);
233
234 /* Exported by fib_semantics.c */
235 extern int ip_fib_check_default(__be32 gw, struct net_device *dev);
236 extern int fib_sync_down_dev(struct net_device *dev, int force);
237 extern int fib_sync_down_addr(struct net *net, __be32 local);
238 extern void fib_update_nh_saddrs(struct net_device *dev);
239 extern int fib_sync_up(struct net_device *dev);
240 extern void fib_select_multipath(struct fib_result *res);
241
242 /* Exported by fib_trie.c */
243 extern void fib_trie_init(void);
244 extern struct fib_table *fib_trie_table(u32 id);
245
fib_combine_itag(u32 * itag,const struct fib_result * res)246 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
247 {
248 #ifdef CONFIG_IP_ROUTE_CLASSID
249 #ifdef CONFIG_IP_MULTIPLE_TABLES
250 u32 rtag;
251 #endif
252 *itag = FIB_RES_NH(*res).nh_tclassid<<16;
253 #ifdef CONFIG_IP_MULTIPLE_TABLES
254 rtag = fib_rules_tclass(res);
255 if (*itag == 0)
256 *itag = (rtag<<16);
257 *itag |= (rtag>>16);
258 #endif
259 #endif
260 }
261
262 extern void free_fib_info(struct fib_info *fi);
263
fib_info_put(struct fib_info * fi)264 static inline void fib_info_put(struct fib_info *fi)
265 {
266 if (atomic_dec_and_test(&fi->fib_clntref))
267 free_fib_info(fi);
268 }
269
270 #ifdef CONFIG_PROC_FS
271 extern int __net_init fib_proc_init(struct net *net);
272 extern void __net_exit fib_proc_exit(struct net *net);
273 #else
fib_proc_init(struct net * net)274 static inline int fib_proc_init(struct net *net)
275 {
276 return 0;
277 }
fib_proc_exit(struct net * net)278 static inline void fib_proc_exit(struct net *net)
279 {
280 }
281 #endif
282
283 #endif /* _NET_FIB_H */
284