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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 <linux/rcupdate.h> 22#include <net/fib_rules.h> 23#include <net/inetpeer.h> 24#include <linux/percpu.h> 25 26struct fib_config { 27 u8 fc_dst_len; 28 u8 fc_tos; 29 u8 fc_protocol; 30 u8 fc_scope; 31 u8 fc_type; 32 /* 3 bytes unused */ 33 u32 fc_table; 34 __be32 fc_dst; 35 __be32 fc_gw; 36 int fc_oif; 37 u32 fc_flags; 38 u32 fc_priority; 39 __be32 fc_prefsrc; 40 struct nlattr *fc_mx; 41 struct rtnexthop *fc_mp; 42 int fc_mx_len; 43 int fc_mp_len; 44 u32 fc_flow; 45 u32 fc_nlflags; 46 struct nl_info fc_nlinfo; 47 }; 48 49struct fib_info; 50struct rtable; 51 52struct fib_nh_exception { 53 struct fib_nh_exception __rcu *fnhe_next; 54 __be32 fnhe_daddr; 55 u32 fnhe_pmtu; 56 __be32 fnhe_gw; 57 unsigned long fnhe_expires; 58 struct rtable __rcu *fnhe_rth; 59 unsigned long fnhe_stamp; 60}; 61 62struct fnhe_hash_bucket { 63 struct fib_nh_exception __rcu *chain; 64}; 65 66#define FNHE_HASH_SIZE 2048 67#define FNHE_RECLAIM_DEPTH 5 68 69struct fib_nh { 70 struct net_device *nh_dev; 71 struct hlist_node nh_hash; 72 struct fib_info *nh_parent; 73 unsigned int nh_flags; 74 unsigned char nh_scope; 75#ifdef CONFIG_IP_ROUTE_MULTIPATH 76 int nh_weight; 77 int nh_power; 78#endif 79#ifdef CONFIG_IP_ROUTE_CLASSID 80 __u32 nh_tclassid; 81#endif 82 int nh_oif; 83 __be32 nh_gw; 84 __be32 nh_saddr; 85 int nh_saddr_genid; 86 struct rtable __rcu * __percpu *nh_pcpu_rth_output; 87 struct rtable __rcu *nh_rth_input; 88 struct fnhe_hash_bucket *nh_exceptions; 89}; 90 91/* 92 * This structure contains data shared by many of routes. 93 */ 94 95struct fib_info { 96 struct hlist_node fib_hash; 97 struct hlist_node fib_lhash; 98 struct net *fib_net; 99 int fib_treeref; 100 atomic_t fib_clntref; 101 unsigned int fib_flags; 102 unsigned char fib_dead; 103 unsigned char fib_protocol; 104 unsigned char fib_scope; 105 unsigned char fib_type; 106 __be32 fib_prefsrc; 107 u32 fib_priority; 108 u32 *fib_metrics; 109#define fib_mtu fib_metrics[RTAX_MTU-1] 110#define fib_window fib_metrics[RTAX_WINDOW-1] 111#define fib_rtt fib_metrics[RTAX_RTT-1] 112#define fib_advmss fib_metrics[RTAX_ADVMSS-1] 113 int fib_nhs; 114#ifdef CONFIG_IP_ROUTE_MULTIPATH 115 int fib_power; 116#endif 117 struct rcu_head rcu; 118 struct fib_nh fib_nh[0]; 119#define fib_dev fib_nh[0].nh_dev 120}; 121 122 123#ifdef CONFIG_IP_MULTIPLE_TABLES 124struct fib_rule; 125#endif 126 127struct fib_table; 128struct fib_result { 129 unsigned char prefixlen; 130 unsigned char nh_sel; 131 unsigned char type; 132 unsigned char scope; 133 u32 tclassid; 134 struct fib_info *fi; 135 struct fib_table *table; 136 struct list_head *fa_head; 137}; 138 139struct fib_result_nl { 140 __be32 fl_addr; /* To be looked up*/ 141 u32 fl_mark; 142 unsigned char fl_tos; 143 unsigned char fl_scope; 144 unsigned char tb_id_in; 145 146 unsigned char tb_id; /* Results */ 147 unsigned char prefixlen; 148 unsigned char nh_sel; 149 unsigned char type; 150 unsigned char scope; 151 int err; 152}; 153 154#ifdef CONFIG_IP_ROUTE_MULTIPATH 155 156#define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel]) 157 158#define FIB_TABLE_HASHSZ 2 159 160#else /* CONFIG_IP_ROUTE_MULTIPATH */ 161 162#define FIB_RES_NH(res) ((res).fi->fib_nh[0]) 163 164#define FIB_TABLE_HASHSZ 256 165 166#endif /* CONFIG_IP_ROUTE_MULTIPATH */ 167 168extern __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh); 169 170#define FIB_RES_SADDR(net, res) \ 171 ((FIB_RES_NH(res).nh_saddr_genid == \ 172 atomic_read(&(net)->ipv4.dev_addr_genid)) ? \ 173 FIB_RES_NH(res).nh_saddr : \ 174 fib_info_update_nh_saddr((net), &FIB_RES_NH(res))) 175#define FIB_RES_GW(res) (FIB_RES_NH(res).nh_gw) 176#define FIB_RES_DEV(res) (FIB_RES_NH(res).nh_dev) 177#define FIB_RES_OIF(res) (FIB_RES_NH(res).nh_oif) 178 179#define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \ 180 FIB_RES_SADDR(net, res)) 181 182struct fib_table { 183 struct hlist_node tb_hlist; 184 u32 tb_id; 185 int tb_default; 186 int tb_num_default; 187 unsigned long tb_data[0]; 188}; 189 190extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, 191 struct fib_result *res, int fib_flags); 192extern int fib_table_insert(struct fib_table *, struct fib_config *); 193extern int fib_table_delete(struct fib_table *, struct fib_config *); 194extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb, 195 struct netlink_callback *cb); 196extern int fib_table_flush(struct fib_table *table); 197extern void fib_free_table(struct fib_table *tb); 198 199 200 201#ifndef CONFIG_IP_MULTIPLE_TABLES 202 203#define TABLE_LOCAL_INDEX 0 204#define TABLE_MAIN_INDEX 1 205 206static inline struct fib_table *fib_get_table(struct net *net, u32 id) 207{ 208 struct hlist_head *ptr; 209 210 ptr = id == RT_TABLE_LOCAL ? 211 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] : 212 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]; 213 return hlist_entry(ptr->first, struct fib_table, tb_hlist); 214} 215 216static inline struct fib_table *fib_new_table(struct net *net, u32 id) 217{ 218 return fib_get_table(net, id); 219} 220 221static inline int fib_lookup(struct net *net, const struct flowi4 *flp, 222 struct fib_result *res) 223{ 224 struct fib_table *table; 225 226 table = fib_get_table(net, RT_TABLE_LOCAL); 227 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 228 return 0; 229 230 table = fib_get_table(net, RT_TABLE_MAIN); 231 if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) 232 return 0; 233 return -ENETUNREACH; 234} 235 236#else /* CONFIG_IP_MULTIPLE_TABLES */ 237extern int __net_init fib4_rules_init(struct net *net); 238extern void __net_exit fib4_rules_exit(struct net *net); 239 240extern struct fib_table *fib_new_table(struct net *net, u32 id); 241extern struct fib_table *fib_get_table(struct net *net, u32 id); 242 243extern int __fib_lookup(struct net *net, struct flowi4 *flp, 244 struct fib_result *res); 245 246static inline int fib_lookup(struct net *net, struct flowi4 *flp, 247 struct fib_result *res) 248{ 249 if (!net->ipv4.fib_has_custom_rules) { 250 res->tclassid = 0; 251 if (net->ipv4.fib_local && 252 !fib_table_lookup(net->ipv4.fib_local, flp, res, 253 FIB_LOOKUP_NOREF)) 254 return 0; 255 if (net->ipv4.fib_main && 256 !fib_table_lookup(net->ipv4.fib_main, flp, res, 257 FIB_LOOKUP_NOREF)) 258 return 0; 259 if (net->ipv4.fib_default && 260 !fib_table_lookup(net->ipv4.fib_default, flp, res, 261 FIB_LOOKUP_NOREF)) 262 return 0; 263 return -ENETUNREACH; 264 } 265 return __fib_lookup(net, flp, res); 266} 267 268#endif /* CONFIG_IP_MULTIPLE_TABLES */ 269 270/* Exported by fib_frontend.c */ 271extern const struct nla_policy rtm_ipv4_policy[]; 272extern void ip_fib_init(void); 273extern __be32 fib_compute_spec_dst(struct sk_buff *skb); 274extern int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, 275 u8 tos, int oif, struct net_device *dev, 276 struct in_device *idev, u32 *itag); 277extern void fib_select_default(struct fib_result *res); 278#ifdef CONFIG_IP_ROUTE_CLASSID 279static inline int fib_num_tclassid_users(struct net *net) 280{ 281 return net->ipv4.fib_num_tclassid_users; 282} 283#else 284static inline int fib_num_tclassid_users(struct net *net) 285{ 286 return 0; 287} 288#endif 289 290/* Exported by fib_semantics.c */ 291extern int ip_fib_check_default(__be32 gw, struct net_device *dev); 292extern int fib_sync_down_dev(struct net_device *dev, int force); 293extern int fib_sync_down_addr(struct net *net, __be32 local); 294extern void fib_update_nh_saddrs(struct net_device *dev); 295extern int fib_sync_up(struct net_device *dev); 296extern void fib_select_multipath(struct fib_result *res); 297 298/* Exported by fib_trie.c */ 299extern void fib_trie_init(void); 300extern struct fib_table *fib_trie_table(u32 id); 301 302static inline void fib_combine_itag(u32 *itag, const struct fib_result *res) 303{ 304#ifdef CONFIG_IP_ROUTE_CLASSID 305#ifdef CONFIG_IP_MULTIPLE_TABLES 306 u32 rtag; 307#endif 308 *itag = FIB_RES_NH(*res).nh_tclassid<<16; 309#ifdef CONFIG_IP_MULTIPLE_TABLES 310 rtag = res->tclassid; 311 if (*itag == 0) 312 *itag = (rtag<<16); 313 *itag |= (rtag>>16); 314#endif 315#endif 316} 317 318extern void free_fib_info(struct fib_info *fi); 319 320static inline void fib_info_put(struct fib_info *fi) 321{ 322 if (atomic_dec_and_test(&fi->fib_clntref)) 323 free_fib_info(fi); 324} 325 326#ifdef CONFIG_PROC_FS 327extern int __net_init fib_proc_init(struct net *net); 328extern void __net_exit fib_proc_exit(struct net *net); 329#else 330static inline int fib_proc_init(struct net *net) 331{ 332 return 0; 333} 334static inline void fib_proc_exit(struct net *net) 335{ 336} 337#endif 338 339#endif /* _NET_FIB_H */