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 int fib_treeref; 73 atomic_t fib_clntref; 74 int fib_dead; 75 unsigned fib_flags; 76 int fib_protocol; 77 __be32 fib_prefsrc; 78 u32 fib_priority; 79 u32 fib_metrics[RTAX_MAX]; 80 #define fib_mtu fib_metrics[RTAX_MTU-1] 81 #define fib_window fib_metrics[RTAX_WINDOW-1] 82 #define fib_rtt fib_metrics[RTAX_RTT-1] 83 #define fib_advmss fib_metrics[RTAX_ADVMSS-1] 84 int fib_nhs; 85 #ifdef CONFIG_IP_ROUTE_MULTIPATH 86 int fib_power; 87 #endif 88 struct fib_nh fib_nh[0]; 89 #define fib_dev fib_nh[0].nh_dev 90 }; 91 92 93 #ifdef CONFIG_IP_MULTIPLE_TABLES 94 struct fib_rule; 95 #endif 96 97 struct fib_result { 98 unsigned char prefixlen; 99 unsigned char nh_sel; 100 unsigned char type; 101 unsigned char scope; 102 struct fib_info *fi; 103 #ifdef CONFIG_IP_MULTIPLE_TABLES 104 struct fib_rule *r; 105 #endif 106 }; 107 108 struct fib_result_nl { 109 __be32 fl_addr; /* To be looked up*/ 110 u32 fl_mark; 111 unsigned char fl_tos; 112 unsigned char fl_scope; 113 unsigned char tb_id_in; 114 115 unsigned char tb_id; /* Results */ 116 unsigned char prefixlen; 117 unsigned char nh_sel; 118 unsigned char type; 119 unsigned char scope; 120 int err; 121 }; 122 123 #ifdef CONFIG_IP_ROUTE_MULTIPATH 124 125 #define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 126 #define FIB_RES_RESET(res) ((res).nh_sel = 0) 127 128 #else /* CONFIG_IP_ROUTE_MULTIPATH */ 129 130 #define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 131 #define FIB_RES_RESET(res) 132 133 #endif /* CONFIG_IP_ROUTE_MULTIPATH */ 134 135 #define FIB_RES_PREFSRC(res) ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res)) 136 #define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 137 #define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 138 #define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 139 140 struct fib_table { 141 struct hlist_node tb_hlist; 142 u32 tb_id; 143 unsigned tb_stamp; 144 int (*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res); 145 int (*tb_insert)(struct fib_table *, struct fib_config *); 146 int (*tb_delete)(struct fib_table *, struct fib_config *); 147 int (*tb_dump)(struct fib_table *table, struct sk_buff *skb, 148 struct netlink_callback *cb); 149 int (*tb_flush)(struct fib_table *table); 150 void (*tb_select_default)(struct fib_table *table, 151 const struct flowi *flp, struct fib_result *res); 152 153 unsigned char tb_data[0]; 154 }; 155 156 #ifndef CONFIG_IP_MULTIPLE_TABLES 157 158 extern struct fib_table *ip_fib_local_table; 159 extern struct fib_table *ip_fib_main_table; 160 161 static inline struct fib_table *fib_get_table(u32 id) 162 { 163 if (id != RT_TABLE_LOCAL) 164 return ip_fib_main_table; 165 return ip_fib_local_table; 166 } 167 168 static inline struct fib_table *fib_new_table(u32 id) 169 { 170 return fib_get_table(id); 171 } 172 173 static inline int fib_lookup(const struct flowi *flp, struct fib_result *res) 174 { 175 if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) && 176 ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res)) 177 return -ENETUNREACH; 178 return 0; 179 } 180 181 static inline void fib_select_default(const struct flowi *flp, struct fib_result *res) 182 { 183 if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) 184 ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res); 185 } 186 187 #else /* CONFIG_IP_MULTIPLE_TABLES */ 188 #define ip_fib_local_table fib_get_table(RT_TABLE_LOCAL) 189 #define ip_fib_main_table fib_get_table(RT_TABLE_MAIN) 190 191 extern int fib_lookup(struct flowi *flp, struct fib_result *res); 192 193 extern struct fib_table *fib_new_table(u32 id); 194 extern struct fib_table *fib_get_table(u32 id); 195 extern void fib_select_default(const struct flowi *flp, struct fib_result *res); 196 197 #endif /* CONFIG_IP_MULTIPLE_TABLES */ 198 199 /* Exported by fib_frontend.c */ 200 extern const struct nla_policy rtm_ipv4_policy[]; 201 extern void ip_fib_init(void); 202 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, 203 struct net_device *dev, __be32 *spec_dst, u32 *itag); 204 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res); 205 206 struct rtentry; 207 208 /* Exported by fib_semantics.c */ 209 extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 210 extern int fib_sync_down(__be32 local, struct net_device *dev, int force); 211 extern int fib_sync_up(struct net_device *dev); 212 extern __be32 __fib_res_prefsrc(struct fib_result *res); 213 214 /* Exported by fib_hash.c */ 215 extern struct fib_table *fib_hash_init(u32 id); 216 217 #ifdef CONFIG_IP_MULTIPLE_TABLES 218 extern void __init fib4_rules_init(void); 219 220 #ifdef CONFIG_NET_CLS_ROUTE 221 extern u32 fib_rules_tclass(struct fib_result *res); 222 #endif 223 224 #endif 225 226 static inline void fib_combine_itag(u32 *itag, struct fib_result *res) 227 { 228 #ifdef CONFIG_NET_CLS_ROUTE 229 #ifdef CONFIG_IP_MULTIPLE_TABLES 230 u32 rtag; 231 #endif 232 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 233 #ifdef CONFIG_IP_MULTIPLE_TABLES 234 rtag = fib_rules_tclass(res); 235 if (*itag == 0) 236 *itag = (rtag<<16); 237 *itag |= (rtag>>16); 238 #endif 239 #endif 240 } 241 242 extern void free_fib_info(struct fib_info *fi); 243 244 static inline void fib_info_put(struct fib_info *fi) 245 { 246 if (atomic_dec_and_test(&fi->fib_clntref)) 247 free_fib_info(fi); 248 } 249 250 static inline void fib_res_put(struct fib_result *res) 251 { 252 if (res->fi) 253 fib_info_put(res->fi); 254 #ifdef CONFIG_IP_MULTIPLE_TABLES 255 if (res->r) 256 fib_rule_put(res->r); 257 #endif 258 } 259 260 #ifdef CONFIG_PROC_FS 261 extern int fib_proc_init(void); 262 extern void fib_proc_exit(void); 263 #endif 264 265 #endif /* _NET_FIB_H */ 266