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 fib_nh fib_nh[0]; 90 #define fib_dev fib_nh[0].nh_dev 91 }; 92 93 94 #ifdef CONFIG_IP_MULTIPLE_TABLES 95 struct fib_rule; 96 #endif 97 98 struct fib_result { 99 unsigned char prefixlen; 100 unsigned char nh_sel; 101 unsigned char type; 102 unsigned char scope; 103 struct fib_info *fi; 104 #ifdef CONFIG_IP_MULTIPLE_TABLES 105 struct fib_rule *r; 106 #endif 107 }; 108 109 struct fib_result_nl { 110 __be32 fl_addr; /* To be looked up*/ 111 u32 fl_mark; 112 unsigned char fl_tos; 113 unsigned char fl_scope; 114 unsigned char tb_id_in; 115 116 unsigned char tb_id; /* Results */ 117 unsigned char prefixlen; 118 unsigned char nh_sel; 119 unsigned char type; 120 unsigned char scope; 121 int err; 122 }; 123 124 #ifdef CONFIG_IP_ROUTE_MULTIPATH 125 126 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 127 128 #define FIB_TABLE_HASHSZ 2 129 130 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 131 132 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 133 134 #define FIB_TABLE_HASHSZ 256 135 136 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 137 138 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res)) 139 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 140 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 141 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 142 143 struct fib_table { 144 struct hlist_node tb_hlist; 145 u32 tb_id; 146 int tb_default; 147 unsigned char tb_data[0]; 148 }; 149 150 extern int fib_table_lookup(struct fib_table *tb, const struct flowi *flp, 151 struct fib_result *res); 152 extern int fib_table_insert(struct fib_table *, struct fib_config *); 153 extern int fib_table_delete(struct fib_table *, struct fib_config *); 154 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 155 struct netlink_callback *cb); 156 extern int fib_table_flush(struct fib_table *table); 157 extern void fib_table_select_default(struct fib_table *table, 158 const struct flowi *flp, 159 struct fib_result *res); 160 161 162 #ifndef CONFIG_IP_MULTIPLE_TABLES 163 164 #define TABLE_LOCAL_INDEX 0 165 #define TABLE_MAIN_INDEX 1 166 167 static inline struct fib_table *fib_get_table(struct net *net, u32 id) 168 { 169 struct hlist_head *ptr; 170 171 ptr = id == RT_TABLE_LOCAL ? 172 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 173 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 174 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 175 } 176 177 static inline struct fib_table *fib_new_table(struct net *net, u32 id) 178 { 179 return fib_get_table(net, id); 180 } 181 182 static inline int fib_lookup(struct net *net, const struct flowi *flp, 183 struct fib_result *res) 184 { 185 struct fib_table *table; 186 187 table = fib_get_table(net, RT_TABLE_LOCAL); 188 if (!fib_table_lookup(table, flp, res)) 189 return 0; 190 191 table = fib_get_table(net, RT_TABLE_MAIN); 192 if (!fib_table_lookup(table, flp, res)) 193 return 0; 194 return -ENETUNREACH; 195 } 196 197 #else /* CONFIG_IP_MULTIPLE_TABLES */ 198 extern int __net_init fib4_rules_init(struct net *net); 199 extern void __net_exit fib4_rules_exit(struct net *net); 200 201 #ifdef CONFIG_NET_CLS_ROUTE 202 extern u32 fib_rules_tclass(struct fib_result *res); 203 #endif 204 205 extern int fib_lookup(struct net *n, struct flowi *flp, struct fib_result *res); 206 207 extern struct fib_table *fib_new_table(struct net *net, u32 id); 208 extern struct fib_table *fib_get_table(struct net *net, u32 id); 209 210 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 211 212 /* Exported by fib_frontend.c */ 213 extern const struct nla_policy rtm_ipv4_policy[]; 214 extern void ip_fib_init(void); 215 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, 216 struct net_device *dev, __be32 *spec_dst, 217 u32 *itag, u32 mark); 218 extern void fib_select_default(struct net *net, const struct flowi *flp, 219 struct fib_result *res); 220 221 /* Exported by fib_semantics.c */ 222 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 223 extern int fib_sync_down_dev(struct net_device *dev, int force); 224 extern int fib_sync_down_addr(struct net *net, __be32 local); 225 extern int fib_sync_up(struct net_device *dev); 226 extern __be32 __fib_res_prefsrc(struct fib_result *res); 227 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res); 228 229 /* Exported by fib_{hash|trie}.c */ 230 extern void fib_hash_init(void); 231 extern struct fib_table *fib_hash_table(u32 id); 232 233 static inline void fib_combine_itag(u32 *itag, struct fib_result *res) 234 { 235 #ifdef CONFIG_NET_CLS_ROUTE 236 #ifdef CONFIG_IP_MULTIPLE_TABLES 237 u32 rtag; 238 #endif 239 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 240 #ifdef CONFIG_IP_MULTIPLE_TABLES 241 rtag = fib_rules_tclass(res); 242 if (*itag == 0) 243 *itag = (rtag<<16); 244 *itag |= (rtag>>16); 245 #endif 246 #endif 247 } 248 249 extern void free_fib_info(struct fib_info *fi); 250 251 static inline void fib_info_put(struct fib_info *fi) 252 { 253 if (atomic_dec_and_test(&fi->fib_clntref)) 254 free_fib_info(fi); 255 } 256 257 static inline void fib_res_put(struct fib_result *res) 258 { 259 if (res->fi) 260 fib_info_put(res->fi); 261 #ifdef CONFIG_IP_MULTIPLE_TABLES 262 if (res->r) 263 fib_rule_put(res->r); 264 #endif 265 } 266 267 #ifdef CONFIG_PROC_FS 268 extern int __net_init fib_proc_init(struct net *net); 269 extern void __net_exit fib_proc_exit(struct net *net); 270 #else 271 static inline int fib_proc_init(struct net *net) 272 { 273 return 0; 274 } 275 static inline void fib_proc_exit(struct net *net) 276 { 277 } 278 #endif 279 280 #endif /* _NET_FIB_H */ 281