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_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 inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 219 extern int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 220 extern int inet_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 221 extern int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb);
 222 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 223                                struct net_device *dev, __be32 *spec_dst, u32 *itag);
 224 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res);
 225
 226 struct rtentry;
 227
 228 /* Exported by fib_semantics.c */
 229 extern int ip_fib_check_default(__be32 gw, struct net_device *dev);
 230 extern int fib_sync_down(__be32 local, struct net_device *dev, int force);
 231 extern int fib_sync_up(struct net_device *dev);
 232 extern __be32  __fib_res_prefsrc(struct fib_result *res);
 233
 234 /* Exported by fib_hash.c */
 235 extern struct fib_table *fib_hash_init(u32 id);
 236
 237 #ifdef CONFIG_IP_MULTIPLE_TABLES
 238 extern int fib4_rules_dump(struct sk_buff *skb, struct netlink_callback *cb);
 239
 240 extern void __init fib4_rules_init(void);
 241
 242 #ifdef CONFIG_NET_CLS_ROUTE
 243 extern u32 fib_rules_tclass(struct fib_result *res);
 244 #endif
 245
 246 #endif
 247
 248 static inline void fib_combine_itag(u32 *itag, struct fib_result *res)
 249 {
 250 #ifdef CONFIG_NET_CLS_ROUTE
 251 #ifdef CONFIG_IP_MULTIPLE_TABLES
 252         u32 rtag;
 253 #endif
 254         *itag = FIB_RES_NH(*res).nh_tclassid<<16;
 255 #ifdef CONFIG_IP_MULTIPLE_TABLES
 256         rtag = fib_rules_tclass(res);
 257         if (*itag == 0)
 258                 *itag = (rtag<<16);
 259         *itag |= (rtag>>16);
 260 #endif
 261 #endif
 262 }
 263
 264 extern void free_fib_info(struct fib_info *fi);
 265
 266 static inline void fib_info_put(struct fib_info *fi)
 267 {
 268         if (atomic_dec_and_test(&fi->fib_clntref))
 269                 free_fib_info(fi);
 270 }
 271
 272 static inline void fib_res_put(struct fib_result *res)
 273 {
 274         if (res->fi)
 275                 fib_info_put(res->fi);
 276 #ifdef CONFIG_IP_MULTIPLE_TABLES
 277         if (res->r)
 278                 fib_rule_put(res->r);
 279 #endif
 280 }
 281
 282 #ifdef CONFIG_PROC_FS
 283 extern int  fib_proc_init(void);
 284 extern void fib_proc_exit(void);
 285 #endif
 286
 287 #endif  /* _NET_FIB_H */