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_NET_CLS_ROUTE 59 __u32 nh_tclassid; 60 #endif 61 int nh_oif; 62 __be32 nh_gw; 63 }; 64 65 /* 66 * This structure contains data shared by many of routes. 67 */ 68 69 struct fib_info { 70 struct hlist_node fib_hash; 71 struct hlist_node fib_lhash; 72 struct net *fib_net; 73 int fib_treeref; 74 atomic_t fib_clntref; 75 int fib_dead; 76 unsigned fib_flags; 77 int fib_protocol; 78 __be32 fib_prefsrc; 79 u32 fib_priority; 80 u32 fib_metrics[RTAX_MAX]; 81 #define fib_mtu fib_metrics[RTAX_MTU-1] 82 #define fib_window fib_metrics[RTAX_WINDOW-1] 83 #define fib_rtt fib_metrics[RTAX_RTT-1] 84 #define fib_advmss fib_metrics[RTAX_ADVMSS-1] 85 int fib_nhs; 86 #ifdef CONFIG_IP_ROUTE_MULTIPATH 87 int fib_power; 88 #endif 89 struct rcu_head rcu; 90 struct fib_nh fib_nh[0]; 91 #define fib_dev fib_nh[0].nh_dev 92 }; 93 94 95 #ifdef CONFIG_IP_MULTIPLE_TABLES 96 struct fib_rule; 97 #endif 98 99 struct fib_result { 100 unsigned char prefixlen; 101 unsigned char nh_sel; 102 unsigned char type; 103 unsigned char scope; 104 struct fib_info *fi; 105 #ifdef CONFIG_IP_MULTIPLE_TABLES 106 struct fib_rule *r; 107 #endif 108 }; 109 110 struct fib_result_nl { 111 __be32 fl_addr; /* To be looked up*/ 112 u32 fl_mark; 113 unsigned char fl_tos; 114 unsigned char fl_scope; 115 unsigned char tb_id_in; 116 117 unsigned char tb_id; /* Results */ 118 unsigned char prefixlen; 119 unsigned char nh_sel; 120 unsigned char type; 121 unsigned char scope; 122 int err; 123 }; 124 125 #ifdef CONFIG_IP_ROUTE_MULTIPATH 126 127 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 128 129 #define FIB_TABLE_HASHSZ 2 130 131 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 132 133 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 134 135 #define FIB_TABLE_HASHSZ 256 136 137 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 138 139 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res)) 140 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 141 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 142 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 143 144 struct fib_table { 145 struct hlist_node tb_hlist; 146 u32 tb_id; 147 int tb_default; 148 unsigned char tb_data[0]; 149 }; 150 151 extern int fib_table_lookup(struct fib_table *tb, const struct flowi *flp, 152 struct fib_result *res, int fib_flags); 153 extern int fib_table_insert(struct fib_table *, struct fib_config *); 154 extern int fib_table_delete(struct fib_table *, struct fib_config *); 155 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 156 struct netlink_callback *cb); 157 extern int fib_table_flush(struct fib_table *table); 158 extern void fib_table_select_default(struct fib_table *table, 159 const struct flowi *flp, 160 struct fib_result *res); 161 extern void fib_free_table(struct fib_table *tb); 162 163 164 165 #ifndef CONFIG_IP_MULTIPLE_TABLES 166 167 #define TABLE_LOCAL_INDEX 0 168 #define TABLE_MAIN_INDEX 1 169 170 static inline struct fib_table *fib_get_table(struct net *net, u32 id) 171 { 172 struct hlist_head *ptr; 173 174 ptr = id == RT_TABLE_LOCAL ? 175 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 176 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 177 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 178 } 179 180 static inline struct fib_table *fib_new_table(struct net *net, u32 id) 181 { 182 return fib_get_table(net, id); 183 } 184 185 static inline int fib_lookup(struct net *net, const struct flowi *flp, 186 struct fib_result *res) 187 { 188 struct fib_table *table; 189 190 table = fib_get_table(net, RT_TABLE_LOCAL); 191 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 192 return 0; 193 194 table = fib_get_table(net, RT_TABLE_MAIN); 195 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 196 return 0; 197 return -ENETUNREACH; 198 } 199 200 #else /* CONFIG_IP_MULTIPLE_TABLES */ 201 extern int __net_init fib4_rules_init(struct net *net); 202 extern void __net_exit fib4_rules_exit(struct net *net); 203 204 #ifdef CONFIG_NET_CLS_ROUTE 205 extern u32 fib_rules_tclass(struct fib_result *res); 206 #endif 207 208 extern int fib_lookup(struct net *n, struct flowi *flp, struct fib_result *res); 209 210 extern struct fib_table *fib_new_table(struct net *net, u32 id); 211 extern struct fib_table *fib_get_table(struct net *net, u32 id); 212 213 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 214 215 /* Exported by fib_frontend.c */ 216 extern const struct nla_policy rtm_ipv4_policy[]; 217 extern void ip_fib_init(void); 218 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, 219 struct net_device *dev, __be32 *spec_dst, 220 u32 *itag, u32 mark); 221 extern void fib_select_default(struct net *net, const struct flowi *flp, 222 struct fib_result *res); 223 224 /* Exported by fib_semantics.c */ 225 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 226 extern int fib_sync_down_dev(struct net_device *dev, int force); 227 extern int fib_sync_down_addr(struct net *net, __be32 local); 228 extern int fib_sync_up(struct net_device *dev); 229 extern __be32 __fib_res_prefsrc(struct fib_result *res); 230 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res); 231 232 /* Exported by fib_{hash|trie}.c */ 233 extern void fib_hash_init(void); 234 extern struct fib_table *fib_hash_table(u32 id); 235 236 static inline void fib_combine_itag(u32 *itag, struct fib_result *res) 237 { 238 #ifdef CONFIG_NET_CLS_ROUTE 239 #ifdef CONFIG_IP_MULTIPLE_TABLES 240 u32 rtag; 241 #endif 242 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 243 #ifdef CONFIG_IP_MULTIPLE_TABLES 244 rtag = fib_rules_tclass(res); 245 if (*itag == 0) 246 *itag = (rtag<<16); 247 *itag |= (rtag>>16); 248 #endif 249 #endif 250 } 251 252 extern void free_fib_info(struct fib_info *fi); 253 254 static inline void fib_info_put(struct fib_info *fi) 255 { 256 if (atomic_dec_and_test(&fi->fib_clntref)) 257 free_fib_info(fi); 258 } 259 260 #ifdef CONFIG_PROC_FS 261 extern int __net_init fib_proc_init(struct net *net); 262 extern void __net_exit fib_proc_exit(struct net *net); 263 #else 264 static inline int fib_proc_init(struct net *net) 265 { 266 return 0; 267 } 268 static inline void fib_proc_exit(struct net *net) 269 { 270 } 271 #endif 272 273 #endif /* _NET_FIB_H */ 274