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 unsigned char nh_cfg_scope; 55 #ifdef CONFIG_IP_ROUTE_MULTIPATH 56 int nh_weight; 57 int nh_power; 58 #endif 59 #ifdef CONFIG_IP_ROUTE_CLASSID 60 __u32 nh_tclassid; 61 #endif 62 int nh_oif; 63 __be32 nh_gw; 64 __be32 nh_saddr; 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 int fib_dead; 78 unsigned fib_flags; 79 int fib_protocol; 80 __be32 fib_prefsrc; 81 u32 fib_priority; 82 u32 *fib_metrics; 83 #define fib_mtu fib_metrics[RTAX_MTU-1] 84 #define fib_window fib_metrics[RTAX_WINDOW-1] 85 #define fib_rtt fib_metrics[RTAX_RTT-1] 86 #define fib_advmss fib_metrics[RTAX_ADVMSS-1] 87 int fib_nhs; 88 #ifdef CONFIG_IP_ROUTE_MULTIPATH 89 int fib_power; 90 #endif 91 struct rcu_head rcu; 92 struct fib_nh fib_nh[0]; 93 #define fib_dev fib_nh[0].nh_dev 94 }; 95 96 97 #ifdef CONFIG_IP_MULTIPLE_TABLES 98 struct fib_rule; 99 #endif 100 101 struct fib_table; 102 struct fib_result { 103 unsigned char prefixlen; 104 unsigned char nh_sel; 105 unsigned char type; 106 unsigned char scope; 107 struct fib_info *fi; 108 struct fib_table *table; 109 struct list_head *fa_head; 110 #ifdef CONFIG_IP_MULTIPLE_TABLES 111 struct fib_rule *r; 112 #endif 113 }; 114 115 struct fib_result_nl { 116 __be32 fl_addr; /* To be looked up*/ 117 u32 fl_mark; 118 unsigned char fl_tos; 119 unsigned char fl_scope; 120 unsigned char tb_id_in; 121 122 unsigned char tb_id; /* Results */ 123 unsigned char prefixlen; 124 unsigned char nh_sel; 125 unsigned char type; 126 unsigned char scope; 127 int err; 128 }; 129 130 #ifdef CONFIG_IP_ROUTE_MULTIPATH 131 132 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 133 134 #define FIB_TABLE_HASHSZ 2 135 136 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 137 138 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 139 140 #define FIB_TABLE_HASHSZ 256 141 142 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 143 144 #define FIB_RES_SADDR(res) (FIB_RES_NH(res).nh_saddr) 145 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 146 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 147 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 148 149 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : FIB_RES_SADDR(res)) 150 151 struct fib_table { 152 struct hlist_node tb_hlist; 153 u32 tb_id; 154 int tb_default; 155 unsigned char tb_data[0]; 156 }; 157 158 extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, 159 struct fib_result *res, int fib_flags); 160 extern int fib_table_insert(struct fib_table *, struct fib_config *); 161 extern int fib_table_delete(struct fib_table *, struct fib_config *); 162 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 163 struct netlink_callback *cb); 164 extern int fib_table_flush(struct fib_table *table); 165 extern void fib_free_table(struct fib_table *tb); 166 167 168 169 #ifndef CONFIG_IP_MULTIPLE_TABLES 170 171 #define TABLE_LOCAL_INDEX 0 172 #define TABLE_MAIN_INDEX 1 173 174 static inline struct fib_table *fib_get_table(struct net *net, u32 id) 175 { 176 struct hlist_head *ptr; 177 178 ptr = id == RT_TABLE_LOCAL ? 179 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 180 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 181 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 182 } 183 184 static inline struct fib_table *fib_new_table(struct net *net, u32 id) 185 { 186 return fib_get_table(net, id); 187 } 188 189 static inline int fib_lookup(struct net *net, const struct flowi4 *flp, 190 struct fib_result *res) 191 { 192 struct fib_table *table; 193 194 table = fib_get_table(net, RT_TABLE_LOCAL); 195 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 196 return 0; 197 198 table = fib_get_table(net, RT_TABLE_MAIN); 199 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 200 return 0; 201 return -ENETUNREACH; 202 } 203 204 #else /* CONFIG_IP_MULTIPLE_TABLES */ 205 extern int __net_init fib4_rules_init(struct net *net); 206 extern void __net_exit fib4_rules_exit(struct net *net); 207 208 #ifdef CONFIG_IP_ROUTE_CLASSID 209 extern u32 fib_rules_tclass(const struct fib_result *res); 210 #endif 211 212 extern int fib_lookup(struct net *n, struct flowi4 *flp, struct fib_result *res); 213 214 extern struct fib_table *fib_new_table(struct net *net, u32 id); 215 extern struct fib_table *fib_get_table(struct net *net, u32 id); 216 217 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 218 219 /* Exported by fib_frontend.c */ 220 extern const struct nla_policy rtm_ipv4_policy[]; 221 extern void ip_fib_init(void); 222 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, 223 struct net_device *dev, __be32 *spec_dst, 224 u32 *itag, u32 mark); 225 extern void fib_select_default(struct fib_result *res); 226 227 /* Exported by fib_semantics.c */ 228 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 229 extern int fib_sync_down_dev(struct net_device *dev, int force); 230 extern int fib_sync_down_addr(struct net *net, __be32 local); 231 extern void fib_update_nh_saddrs(struct net_device *dev); 232 extern int fib_sync_up(struct net_device *dev); 233 extern void fib_select_multipath(struct fib_result *res); 234 235 /* Exported by fib_trie.c */ 236 extern void fib_trie_init(void); 237 extern struct fib_table *fib_trie_table(u32 id); 238 239 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res) 240 { 241 #ifdef CONFIG_IP_ROUTE_CLASSID 242 #ifdef CONFIG_IP_MULTIPLE_TABLES 243 u32 rtag; 244 #endif 245 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 246 #ifdef CONFIG_IP_MULTIPLE_TABLES 247 rtag = fib_rules_tclass(res); 248 if (*itag == 0) 249 *itag = (rtag<<16); 250 *itag |= (rtag>>16); 251 #endif 252 #endif 253 } 254 255 extern void free_fib_info(struct fib_info *fi); 256 257 static inline void fib_info_put(struct fib_info *fi) 258 { 259 if (atomic_dec_and_test(&fi->fib_clntref)) 260 free_fib_info(fi); 261 } 262 263 #ifdef CONFIG_PROC_FS 264 extern int __net_init fib_proc_init(struct net *net); 265 extern void __net_exit fib_proc_exit(struct net *net); 266 #else 267 static inline int fib_proc_init(struct net *net) 268 { 269 return 0; 270 } 271 static inline void fib_proc_exit(struct net *net) 272 { 273 } 274 #endif 275 276 #endif /* _NET_FIB_H */ 277