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 132 133 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 134 135 #define FIB_TABLE_HASHSZ 2 136 137 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 138 139 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 140 141 #define FIB_TABLE_HASHSZ 256 142 143 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 144 145 extern __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh); 146 147 #define FIB_RES_SADDR(net, res) \ 148 ((FIB_RES_NH(res).nh_saddr_genid == \ 149 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \ 150 FIB_RES_NH(res).nh_saddr : \ 151 fib_info_update_nh_saddr((net), &FIB_RES_NH(res))) 152 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 153 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 154 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 155 156 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \ 157 FIB_RES_SADDR(net, res)) 158 159 struct fib_table { 160 struct hlist_node tb_hlist; 161 u32 tb_id; 162 int tb_default; 163 int tb_num_default; 164 unsigned long tb_data[0]; 165 }; 166 167 extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, 168 struct fib_result *res, int fib_flags); 169 extern int fib_table_insert(struct fib_table *, struct fib_config *); 170 extern int fib_table_delete(struct fib_table *, struct fib_config *); 171 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 172 struct netlink_callback *cb); 173 extern int fib_table_flush(struct fib_table *table); 174 extern void fib_free_table(struct fib_table *tb); 175 176 177 178 #ifndef CONFIG_IP_MULTIPLE_TABLES 179 180 #define TABLE_LOCAL_INDEX 0 181 #define TABLE_MAIN_INDEX 1 182 183 static inline struct fib_table *fib_get_table(struct net *net, u32 id) 184 { 185 struct hlist_head *ptr; 186 187 ptr = id == RT_TABLE_LOCAL ? 188 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 189 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 190 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 191 } 192 193 static inline struct fib_table *fib_new_table(struct net *net, u32 id) 194 { 195 return fib_get_table(net, id); 196 } 197 198 static inline int fib_lookup(struct net *net, const struct flowi4 *flp, 199 struct fib_result *res) 200 { 201 struct fib_table *table; 202 203 table = fib_get_table(net, RT_TABLE_LOCAL); 204 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 205 return 0; 206 207 table = fib_get_table(net, RT_TABLE_MAIN); 208 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 209 return 0; 210 return -ENETUNREACH; 211 } 212 213 #else /* CONFIG_IP_MULTIPLE_TABLES */ 214 extern int __net_init fib4_rules_init(struct net *net); 215 extern void __net_exit fib4_rules_exit(struct net *net); 216 217 #ifdef CONFIG_IP_ROUTE_CLASSID 218 extern u32 fib_rules_tclass(const struct fib_result *res); 219 #endif 220 221 extern int fib_lookup(struct net *n, struct flowi4 *flp, struct fib_result *res); 222 223 extern struct fib_table *fib_new_table(struct net *net, u32 id); 224 extern struct fib_table *fib_get_table(struct net *net, u32 id); 225 226 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 227 228 /* Exported by fib_frontend.c */ 229 extern const struct nla_policy rtm_ipv4_policy[]; 230 extern void ip_fib_init(void); 231 extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 232 u8 tos, int oif, struct net_device *dev, 233 __be32 *spec_dst, u32 *itag); 234 extern void fib_select_default(struct fib_result *res); 235 236 /* Exported by fib_semantics.c */ 237 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 238 extern int fib_sync_down_dev(struct net_device *dev, int force); 239 extern int fib_sync_down_addr(struct net *net, __be32 local); 240 extern void fib_update_nh_saddrs(struct net_device *dev); 241 extern int fib_sync_up(struct net_device *dev); 242 extern void fib_select_multipath(struct fib_result *res); 243 244 /* Exported by fib_trie.c */ 245 extern void fib_trie_init(void); 246 extern struct fib_table *fib_trie_table(u32 id); 247 248 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res) 249 { 250 #ifdef CONFIG_IP_ROUTE_CLASSID 251 #ifdef CONFIG_IP_MULTIPLE_TABLES 252 u32 rtag; 253 #endif 254 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 255 #ifdef CONFIG_IP_MULTIPLE_TABLES 256 rtag = fib_rules_tclass(res); 257 if (*itag == 0) 258 *itag = (rtag<<16); 259 *itag |= (rtag>>16); 260 #endif 261 #endif 262 } 263 264 extern void free_fib_info(struct fib_info *fi); 265 266 static inline void fib_info_put(struct fib_info *fi) 267 { 268 if (atomic_dec_and_test(&fi->fib_clntref)) 269 free_fib_info(fi); 270 } 271 272 #ifdef CONFIG_PROC_FS 273 extern int __net_init fib_proc_init(struct net *net); 274 extern void __net_exit fib_proc_exit(struct net *net); 275 #else 276 static inline int fib_proc_init(struct net *net) 277 { 278 return 0; 279 } 280 static inline void fib_proc_exit(struct net *net) 281 { 282 } 283 #endif 284 285 #endif /* _NET_FIB_H */ 286