include/net/ip_fib.h

   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         unsigned char           nh_cfg_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 };
  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         int                     fib_dead;
  78         unsigned                fib_flags;
  79         int                     fib_protocol;
  80         __be32                  fib_prefsrc;
  81         u32                     fib_priority;
  82         u32                     *fib_metrics;
  83 #define fib_mtu fib_metrics[RTAX_MTU-1]
  84 #define fib_window fib_metrics[RTAX_WINDOW-1]
  85 #define fib_rtt fib_metrics[RTAX_RTT-1]
  86 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
  87         int                     fib_nhs;
  88 #ifdef CONFIG_IP_ROUTE_MULTIPATH
  89         int                     fib_power;
  90 #endif
  91         struct rcu_head         rcu;
  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_table;
 102 struct fib_result {
 103         unsigned char   prefixlen;
 104         unsigned char   nh_sel;
 105         unsigned char   type;
 106         unsigned char   scope;
 107         struct fib_info *fi;
 108         struct fib_table *table;
 109         struct list_head *fa_head;
 110 #ifdef CONFIG_IP_MULTIPLE_TABLES
 111         struct fib_rule *r;
 112 #endif
 113 };
 114
 115 struct fib_result_nl {
 116         __be32          fl_addr;   /* To be looked up*/
 117         u32             fl_mark;
 118         unsigned char   fl_tos;
 119         unsigned char   fl_scope;
 120         unsigned char   tb_id_in;
 121
 122         unsigned char   tb_id;      /* Results */
 123         unsigned char   prefixlen;
 124         unsigned char   nh_sel;
 125         unsigned char   type;
 126         unsigned char   scope;
 127         int             err;
 128 };
 129
 130 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 131
 132 #define FIB_RES_NH(res)         ((res).fi->fib_nh[(res).nh_sel])
 133
 134 #define FIB_TABLE_HASHSZ 2
 135
 136 #else /* CONFIG_IP_ROUTE_MULTIPATH */
 137
 138 #define FIB_RES_NH(res)         ((res).fi->fib_nh[0])
 139
 140 #define FIB_TABLE_HASHSZ 256
 141
 142 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
 143
 144 #define FIB_RES_SADDR(res)              (FIB_RES_NH(res).nh_saddr)
 145 #define FIB_RES_GW(res)                 (FIB_RES_NH(res).nh_gw)
 146 #define FIB_RES_DEV(res)                (FIB_RES_NH(res).nh_dev)
 147 #define FIB_RES_OIF(res)                (FIB_RES_NH(res).nh_oif)
 148
 149 #define FIB_RES_PREFSRC(res)            ((res).fi->fib_prefsrc ? : FIB_RES_SADDR(res))
 150
 151 struct fib_table {
 152         struct hlist_node tb_hlist;
 153         u32             tb_id;
 154         int             tb_default;
 155         unsigned char   tb_data[0];
 156 };
 157
 158 extern int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
 159                             struct fib_result *res, int fib_flags);
 160 extern int fib_table_insert(struct fib_table *, struct fib_config *);
 161 extern int fib_table_delete(struct fib_table *, struct fib_config *);
 162 extern int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
 163                           struct netlink_callback *cb);
 164 extern int fib_table_flush(struct fib_table *table);
 165 extern void fib_free_table(struct fib_table *tb);
 166
 167
 168
 169 #ifndef CONFIG_IP_MULTIPLE_TABLES
 170
 171 #define TABLE_LOCAL_INDEX       0
 172 #define TABLE_MAIN_INDEX        1
 173
 174 static inline struct fib_table *fib_get_table(struct net *net, u32 id)
 175 {
 176         struct hlist_head *ptr;
 177
 178         ptr = id == RT_TABLE_LOCAL ?
 179                 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX] :
 180                 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX];
 181         return hlist_entry(ptr->first, struct fib_table, tb_hlist);
 182 }
 183
 184 static inline struct fib_table *fib_new_table(struct net *net, u32 id)
 185 {
 186         return fib_get_table(net, id);
 187 }
 188
 189 static inline int fib_lookup(struct net *net, const struct flowi4 *flp,
 190                              struct fib_result *res)
 191 {
 192         struct fib_table *table;
 193
 194         table = fib_get_table(net, RT_TABLE_LOCAL);
 195         if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
 196                 return 0;
 197
 198         table = fib_get_table(net, RT_TABLE_MAIN);
 199         if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF))
 200                 return 0;
 201         return -ENETUNREACH;
 202 }
 203
 204 #else /* CONFIG_IP_MULTIPLE_TABLES */
 205 extern int __net_init fib4_rules_init(struct net *net);
 206 extern void __net_exit fib4_rules_exit(struct net *net);
 207
 208 #ifdef CONFIG_IP_ROUTE_CLASSID
 209 extern u32 fib_rules_tclass(const struct fib_result *res);
 210 #endif
 211
 212 extern int fib_lookup(struct net *n, struct flowi4 *flp, struct fib_result *res);
 213
 214 extern struct fib_table *fib_new_table(struct net *net, u32 id);
 215 extern struct fib_table *fib_get_table(struct net *net, u32 id);
 216
 217 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 218
 219 /* Exported by fib_frontend.c */
 220 extern const struct nla_policy rtm_ipv4_policy[];
 221 extern void             ip_fib_init(void);
 222 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 223                                struct net_device *dev, __be32 *spec_dst,
 224                                u32 *itag, u32 mark);
 225 extern void fib_select_default(struct fib_result *res);
 226
 227 /* Exported by fib_semantics.c */
 228 extern int ip_fib_check_default(__be32 gw, struct net_device *dev);
 229 extern int fib_sync_down_dev(struct net_device *dev, int force);
 230 extern int fib_sync_down_addr(struct net *net, __be32 local);
 231 extern void fib_update_nh_saddrs(struct net_device *dev);
 232 extern int fib_sync_up(struct net_device *dev);
 233 extern void fib_select_multipath(struct fib_result *res);
 234
 235 /* Exported by fib_trie.c */
 236 extern void fib_trie_init(void);
 237 extern struct fib_table *fib_trie_table(u32 id);
 238
 239 static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
 240 {
 241 #ifdef CONFIG_IP_ROUTE_CLASSID
 242 #ifdef CONFIG_IP_MULTIPLE_TABLES
 243         u32 rtag;
 244 #endif
 245         *itag = FIB_RES_NH(*res).nh_tclassid<<16;
 246 #ifdef CONFIG_IP_MULTIPLE_TABLES
 247         rtag = fib_rules_tclass(res);
 248         if (*itag == 0)
 249                 *itag = (rtag<<16);
 250         *itag |= (rtag>>16);
 251 #endif
 252 #endif
 253 }
 254
 255 extern void free_fib_info(struct fib_info *fi);
 256
 257 static inline void fib_info_put(struct fib_info *fi)
 258 {
 259         if (atomic_dec_and_test(&fi->fib_clntref))
 260                 free_fib_info(fi);
 261 }
 262
 263 #ifdef CONFIG_PROC_FS
 264 extern int __net_init  fib_proc_init(struct net *net);
 265 extern void __net_exit fib_proc_exit(struct net *net);
 266 #else
 267 static inline int fib_proc_init(struct net *net)
 268 {
 269         return 0;
 270 }
 271 static inline void fib_proc_exit(struct net *net)
 272 {
 273 }
 274 #endif
 275
 276 #endif  /* _NET_FIB_H */