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_mp_alg; 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 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_NET_CLS_ROUTE 60 __u32 nh_tclassid; 61 #endif 62 int nh_oif; 63 __be32 nh_gw; 64 }; 65 66 /* 67 * This structure contains data shared by many of routes. 68 */ 69 70 struct fib_info { 71 struct hlist_node fib_hash; 72 struct hlist_node fib_lhash; 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 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED 90 u32 fib_mp_alg; 91 #endif 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_result { 102 unsigned char prefixlen; 103 unsigned char nh_sel; 104 unsigned char type; 105 unsigned char scope; 106 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED 107 __be32 network; 108 __be32 netmask; 109 #endif 110 struct fib_info *fi; 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 #define FIB_RES_RESET(res) ((res).nh_sel = 0) 135 136 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 137 138 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 139 #define FIB_RES_RESET(res) 140 141 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 142 143 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res)) 144 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 145 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 146 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 147 148 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED 149 #define FIB_RES_NETWORK(res) ((res).network) 150 #define FIB_RES_NETMASK(res) ((res).netmask) 151 #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ 152 #define FIB_RES_NETWORK(res) (0) 153 #define FIB_RES_NETMASK(res) (0) 154 #endif /* CONFIG_IP_ROUTE_MULTIPATH_WRANDOM */ 155 156 struct fib_table { 157 struct hlist_node tb_hlist; 158 u32 tb_id; 159 unsigned tb_stamp; 160 int (*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res); 161 int (*tb_insert)(struct fib_table *, struct fib_config *); 162 int (*tb_delete)(struct fib_table *, struct fib_config *); 163 int (*tb_dump)(struct fib_table *table, struct sk_buff *skb, 164 struct netlink_callback *cb); 165 int (*tb_flush)(struct fib_table *table); 166 void (*tb_select_default)(struct fib_table *table, 167 const struct flowi *flp, struct fib_result *res); 168 169 unsigned char tb_data[0]; 170 }; 171 172 #ifndef CONFIG_IP_MULTIPLE_TABLES 173 174 extern struct fib_table *ip_fib_local_table; 175 extern struct fib_table *ip_fib_main_table; 176 177 static inline struct fib_table *fib_get_table(u32 id) 178 { 179 if (id != RT_TABLE_LOCAL) 180 return ip_fib_main_table; 181 return ip_fib_local_table; 182 } 183 184 static inline struct fib_table *fib_new_table(u32 id) 185 { 186 return fib_get_table(id); 187 } 188 189 static inline int fib_lookup(const struct flowi *flp, struct fib_result *res) 190 { 191 if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) && 192 ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res)) 193 return -ENETUNREACH; 194 return 0; 195 } 196 197 static inline void fib_select_default(const struct flowi *flp, struct fib_result *res) 198 { 199 if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) 200 ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res); 201 } 202 203 #else /* CONFIG_IP_MULTIPLE_TABLES */ 204 #define ip_fib_local_table fib_get_table(RT_TABLE_LOCAL) 205 #define ip_fib_main_table fib_get_table(RT_TABLE_MAIN) 206 207 extern int fib_lookup(struct flowi *flp, struct fib_result *res); 208 209 extern struct fib_table *fib_new_table(u32 id); 210 extern struct fib_table *fib_get_table(u32 id); 211 extern void fib_select_default(const struct flowi *flp, struct fib_result *res); 212 213 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 214 215 /* Exported by fib_frontend.c */ 216 extern 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, u32 *itag); 220 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res); 221 222 struct rtentry; 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(__be32 local, struct net_device *dev, int force); 227 extern int fib_sync_up(struct net_device *dev); 228 extern __be32 __fib_res_prefsrc(struct fib_result *res); 229 230 /* Exported by fib_hash.c */ 231 extern struct fib_table *fib_hash_init(u32 id); 232 233 #ifdef CONFIG_IP_MULTIPLE_TABLES 234 extern void __init fib4_rules_init(void); 235 236 #ifdef CONFIG_NET_CLS_ROUTE 237 extern u32 fib_rules_tclass(struct fib_result *res); 238 #endif 239 240 #endif 241 242 static inline void fib_combine_itag(u32 *itag, struct fib_result *res) 243 { 244 #ifdef CONFIG_NET_CLS_ROUTE 245 #ifdef CONFIG_IP_MULTIPLE_TABLES 246 u32 rtag; 247 #endif 248 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 249 #ifdef CONFIG_IP_MULTIPLE_TABLES 250 rtag = fib_rules_tclass(res); 251 if (*itag == 0) 252 *itag = (rtag<<16); 253 *itag |= (rtag>>16); 254 #endif 255 #endif 256 } 257 258 extern void free_fib_info(struct fib_info *fi); 259 260 static inline void fib_info_put(struct fib_info *fi) 261 { 262 if (atomic_dec_and_test(&fi->fib_clntref)) 263 free_fib_info(fi); 264 } 265 266 static inline void fib_res_put(struct fib_result *res) 267 { 268 if (res->fi) 269 fib_info_put(res->fi); 270 #ifdef CONFIG_IP_MULTIPLE_TABLES 271 if (res->r) 272 fib_rule_put(res->r); 273 #endif 274 } 275 276 #ifdef CONFIG_PROC_FS 277 extern int fib_proc_init(void); 278 extern void fib_proc_exit(void); 279 #endif 280 281 #endif /* _NET_FIB_H */ 282