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, <[email protected]> 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 #include <net/inetpeer.h> 23 24 struct fib_config { 25 u8 fc_dst_len; 26 u8 fc_tos; 27 u8 fc_protocol; 28 u8 fc_scope; 29 u8 fc_type; 30 /* 3 bytes unused */ 31 u32 fc_table; 32 __be32 fc_dst; 33 __be32 fc_gw; 34 int fc_oif; 35 u32 fc_flags; 36 u32 fc_priority; 37 __be32 fc_prefsrc; 38 struct nlattr *fc_mx; 39 struct rtnexthop *fc_mp; 40 int fc_mx_len; 41 int fc_mp_len; 42 u32 fc_flow; 43 u32 fc_nlflags; 44 struct nl_info fc_nlinfo; 45 }; 46 47 struct fib_info; 48 49 struct fib_nh { 50 struct net_device *nh_dev; 51 struct hlist_node nh_hash; 52 struct fib_info *nh_parent; 53 unsigned int nh_flags; 54 unsigned char nh_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 int nh_saddr_genid; 66 }; 67 68 /* 69 * This structure contains data shared by many of routes. 70 */ 71 72 struct fib_info { 73 struct hlist_node fib_hash; 74 struct hlist_node fib_lhash; 75 struct net *fib_net; 76 int fib_treeref; 77 atomic_t fib_clntref; 78 unsigned int fib_flags; 79 unsigned char fib_dead; 80 unsigned char fib_protocol; 81 unsigned char fib_scope; 82 __be32 fib_prefsrc; 83 u32 fib_priority; 84 u32 *fib_metrics; 85 #define fib_mtu fib_metrics[RTAX_MTU-1] 86 #define fib_window fib_metrics[RTAX_WINDOW-1] 87 #define fib_rtt fib_metrics[RTAX_RTT-1] 88 #define fib_advmss fib_metrics[RTAX_ADVMSS-1] 89 int fib_nhs; 90 #ifdef CONFIG_IP_ROUTE_MULTIPATH 91 int fib_power; 92 #endif 93 struct rcu_head rcu; 94 struct fib_nh fib_nh[0]; 95 #define fib_dev fib_nh[0].nh_dev 96 }; 97 98 99 #ifdef CONFIG_IP_MULTIPLE_TABLES 100 struct fib_rule; 101 #endif 102 103 struct fib_table; 104 struct fib_result { 105 unsigned char prefixlen; 106 unsigned char nh_sel; 107 unsigned char type; 108 unsigned char scope; 109 struct fib_info *fi; 110 struct fib_table *table; 111 struct list_head *fa_head; 112 #ifdef CONFIG_IP_MULTIPLE_TABLES 113 struct fib_rule *r; 114 #endif 115 }; 116 117 struct fib_result_nl { 118 __be32 fl_addr; /* To be looked up*/ 119 u32 fl_mark; 120 unsigned char fl_tos; 121 unsigned char fl_scope; 122 unsigned char tb_id_in; 123 124 unsigned char tb_id; /* Results */ 125 unsigned char prefixlen; 126 unsigned char nh_sel; 127 unsigned char type; 128 unsigned char scope; 129 int err; 130 }; 131 132 #ifdef CONFIG_IP_ROUTE_MULTIPATH 133 134 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 135 136 #define FIB_TABLE_HASHSZ 2 137 138 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 139 140 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 141 142 #define FIB_TABLE_HASHSZ 256 143 144 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 145 146 extern __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh); 147 148 #define FIB_RES_SADDR(net, res) \ 149 ((FIB_RES_NH(res).nh_saddr_genid == \ 150 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \ 151 FIB_RES_NH(res).nh_saddr : \ 152 fib_info_update_nh_saddr((net), &FIB_RES_NH(res))) 153 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 154 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 155 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 156 157 #define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \ 158 FIB_RES_SADDR(net, res)) 159 160 struct fib_table { 161 struct hlist_node tb_hlist; 162 u32 tb_id; 163 int tb_default; 164 int tb_num_default; 165 struct inet_peer_base tb_peers; 166 unsigned long tb_data[0]; 167 }; 168 169 extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, 170 struct fib_result *res, int fib_flags); 171 extern int fib_table_insert(struct fib_table *, struct fib_config *); 172 extern int fib_table_delete(struct fib_table *, struct fib_config *); 173 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 174 struct netlink_callback *cb); 175 extern int fib_table_flush(struct fib_table *table); 176 extern void fib_free_table(struct fib_table *tb); 177 178 179 180 #ifndef CONFIG_IP_MULTIPLE_TABLES 181 182 #define TABLE_LOCAL_INDEX 0 183 #define TABLE_MAIN_INDEX 1 184 185 static inline struct fib_table *fib_get_table(struct net *net, u32 id) 186 { 187 struct hlist_head *ptr; 188 189 ptr = id == RT_TABLE_LOCAL ? 190 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 191 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 192 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 193 } 194 195 static inline struct fib_table *fib_new_table(struct net *net, u32 id) 196 { 197 return fib_get_table(net, id); 198 } 199 200 static inline int fib_lookup(struct net *net, const struct flowi4 *flp, 201 struct fib_result *res) 202 { 203 struct fib_table *table; 204 205 table = fib_get_table(net, RT_TABLE_LOCAL); 206 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 207 return 0; 208 209 table = fib_get_table(net, RT_TABLE_MAIN); 210 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 211 return 0; 212 return -ENETUNREACH; 213 } 214 215 #else /* CONFIG_IP_MULTIPLE_TABLES */ 216 extern int __net_init fib4_rules_init(struct net *net); 217 extern void __net_exit fib4_rules_exit(struct net *net); 218 219 #ifdef CONFIG_IP_ROUTE_CLASSID 220 extern u32 fib_rules_tclass(const struct fib_result *res); 221 #endif 222 223 extern int fib_lookup(struct net *n, struct flowi4 *flp, struct fib_result *res); 224 225 extern struct fib_table *fib_new_table(struct net *net, u32 id); 226 extern struct fib_table *fib_get_table(struct net *net, u32 id); 227 228 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 229 230 /* Exported by fib_frontend.c */ 231 extern const struct nla_policy rtm_ipv4_policy[]; 232 extern void ip_fib_init(void); 233 extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 234 u8 tos, int oif, struct net_device *dev, 235 __be32 *spec_dst, u32 *itag); 236 extern void fib_select_default(struct fib_result *res); 237 238 /* Exported by fib_semantics.c */ 239 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 240 extern int fib_sync_down_dev(struct net_device *dev, int force); 241 extern int fib_sync_down_addr(struct net *net, __be32 local); 242 extern void fib_update_nh_saddrs(struct net_device *dev); 243 extern int fib_sync_up(struct net_device *dev); 244 extern void fib_select_multipath(struct fib_result *res); 245 246 /* Exported by fib_trie.c */ 247 extern void fib_trie_init(void); 248 extern struct fib_table *fib_trie_table(u32 id); 249 250 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res) 251 { 252 #ifdef CONFIG_IP_ROUTE_CLASSID 253 #ifdef CONFIG_IP_MULTIPLE_TABLES 254 u32 rtag; 255 #endif 256 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 257 #ifdef CONFIG_IP_MULTIPLE_TABLES 258 rtag = fib_rules_tclass(res); 259 if (*itag == 0) 260 *itag = (rtag<<16); 261 *itag |= (rtag>>16); 262 #endif 263 #endif 264 } 265 266 extern void free_fib_info(struct fib_info *fi); 267 268 static inline void fib_info_put(struct fib_info *fi) 269 { 270 if (atomic_dec_and_test(&fi->fib_clntref)) 271 free_fib_info(fi); 272 } 273 274 #ifdef CONFIG_PROC_FS 275 extern int __net_init fib_proc_init(struct net *net); 276 extern void __net_exit fib_proc_exit(struct net *net); 277 #else 278 static inline int fib_proc_init(struct net *net) 279 { 280 return 0; 281 } 282 static inline void fib_proc_exit(struct net *net) 283 { 284 } 285 #endif 286 287 #endif /* _NET_FIB_H */ 288