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_family;
  25         u8                      fc_dst_len;
  26         u8                      fc_src_len;
  27         u8                      fc_tos;
  28         u8                      fc_protocol;
  29         u8                      fc_scope;
  30         u8                      fc_type;
  31         /* 1 byte unused */
  32         u32                     fc_table;
  33         __be32                  fc_dst;
  34         __be32                  fc_src;
  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_mp_alg;
  46         u32                     fc_nlflags;
  47         struct nl_info          fc_nlinfo;
  48  };
  49
  50 struct fib_info;
  51
  52 struct fib_nh {
  53         struct net_device       *nh_dev;
  54         struct hlist_node       nh_hash;
  55         struct fib_info         *nh_parent;
  56         unsigned                nh_flags;
  57         unsigned char           nh_scope;
  58 #ifdef CONFIG_IP_ROUTE_MULTIPATH
  59         int                     nh_weight;
  60         int                     nh_power;
  61 #endif
  62 #ifdef CONFIG_NET_CLS_ROUTE
  63         __u32                   nh_tclassid;
  64 #endif
  65         int                     nh_oif;
  66         __be32                  nh_gw;
  67 };
  68
  69 /*
  70  * This structure contains data shared by many of routes.
  71  */
  72
  73 struct fib_info {
  74         struct hlist_node       fib_hash;
  75         struct hlist_node       fib_lhash;
  76         int                     fib_treeref;
  77         atomic_t                fib_clntref;
  78         int                     fib_dead;
  79         unsigned                fib_flags;
  80         int                     fib_protocol;
  81         __be32                  fib_prefsrc;
  82         u32                     fib_priority;
  83         u32                     fib_metrics[RTAX_MAX];
  84 #define fib_mtu fib_metrics[RTAX_MTU-1]
  85 #define fib_window fib_metrics[RTAX_WINDOW-1]
  86 #define fib_rtt fib_metrics[RTAX_RTT-1]
  87 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
  88         int                     fib_nhs;
  89 #ifdef CONFIG_IP_ROUTE_MULTIPATH
  90         int                     fib_power;
  91 #endif
  92 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
  93         u32                     fib_mp_alg;
  94 #endif
  95         struct fib_nh           fib_nh[0];
  96 #define fib_dev         fib_nh[0].nh_dev
  97 };
  98
  99
 100 #ifdef CONFIG_IP_MULTIPLE_TABLES
 101 struct fib_rule;
 102 #endif
 103
 104 struct fib_result {
 105         unsigned char   prefixlen;
 106         unsigned char   nh_sel;
 107         unsigned char   type;
 108         unsigned char   scope;
 109 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
 110         __u32           network;
 111         __u32           netmask;
 112 #endif
 113         struct fib_info *fi;
 114 #ifdef CONFIG_IP_MULTIPLE_TABLES
 115         struct fib_rule *r;
 116 #endif
 117 };
 118
 119 struct fib_result_nl {
 120         u32             fl_addr;   /* To be looked up*/
 121         u32             fl_fwmark;
 122         unsigned char   fl_tos;
 123         unsigned char   fl_scope;
 124         unsigned char   tb_id_in;
 125
 126         unsigned char   tb_id;      /* Results */
 127         unsigned char   prefixlen;
 128         unsigned char   nh_sel;
 129         unsigned char   type;
 130         unsigned char   scope;
 131         int             err;
 132 };
 133
 134 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 135
 136 #define FIB_RES_NH(res)         ((res).fi->fib_nh[(res).nh_sel])
 137 #define FIB_RES_RESET(res)      ((res).nh_sel = 0)
 138
 139 #else /* CONFIG_IP_ROUTE_MULTIPATH */
 140
 141 #define FIB_RES_NH(res)         ((res).fi->fib_nh[0])
 142 #define FIB_RES_RESET(res)
 143
 144 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
 145
 146 #define FIB_RES_PREFSRC(res)            ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res))
 147 #define FIB_RES_GW(res)                 (FIB_RES_NH(res).nh_gw)
 148 #define FIB_RES_DEV(res)                (FIB_RES_NH(res).nh_dev)
 149 #define FIB_RES_OIF(res)                (FIB_RES_NH(res).nh_oif)
 150
 151 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
 152 #define FIB_RES_NETWORK(res)            ((res).network)
 153 #define FIB_RES_NETMASK(res)            ((res).netmask)
 154 #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */
 155 #define FIB_RES_NETWORK(res)            (0)
 156 #define FIB_RES_NETMASK(res)            (0)
 157 #endif /* CONFIG_IP_ROUTE_MULTIPATH_WRANDOM */
 158
 159 struct fib_table {
 160         struct hlist_node tb_hlist;
 161         u32             tb_id;
 162         unsigned        tb_stamp;
 163         int             (*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res);
 164         int             (*tb_insert)(struct fib_table *, struct fib_config *);
 165         int             (*tb_delete)(struct fib_table *, struct fib_config *);
 166         int             (*tb_dump)(struct fib_table *table, struct sk_buff *skb,
 167                                      struct netlink_callback *cb);
 168         int             (*tb_flush)(struct fib_table *table);
 169         void            (*tb_select_default)(struct fib_table *table,
 170                                              const struct flowi *flp, struct fib_result *res);
 171
 172         unsigned char   tb_data[0];
 173 };
 174
 175 #ifndef CONFIG_IP_MULTIPLE_TABLES
 176
 177 extern struct fib_table *ip_fib_local_table;
 178 extern struct fib_table *ip_fib_main_table;
 179
 180 static inline struct fib_table *fib_get_table(u32 id)
 181 {
 182         if (id != RT_TABLE_LOCAL)
 183                 return ip_fib_main_table;
 184         return ip_fib_local_table;
 185 }
 186
 187 static inline struct fib_table *fib_new_table(u32 id)
 188 {
 189         return fib_get_table(id);
 190 }
 191
 192 static inline int fib_lookup(const struct flowi *flp, struct fib_result *res)
 193 {
 194         if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) &&
 195             ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res))
 196                 return -ENETUNREACH;
 197         return 0;
 198 }
 199
 200 static inline void fib_select_default(const struct flowi *flp, struct fib_result *res)
 201 {
 202         if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 203                 ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res);
 204 }
 205
 206 #else /* CONFIG_IP_MULTIPLE_TABLES */
 207 #define ip_fib_local_table fib_get_table(RT_TABLE_LOCAL)
 208 #define ip_fib_main_table fib_get_table(RT_TABLE_MAIN)
 209
 210 extern int fib_lookup(struct flowi *flp, struct fib_result *res);
 211
 212 extern struct fib_table *fib_new_table(u32 id);
 213 extern struct fib_table *fib_get_table(u32 id);
 214 extern void fib_select_default(const struct flowi *flp, struct fib_result *res);
 215
 216 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 217
 218 /* Exported by fib_frontend.c */
 219 extern struct nla_policy rtm_ipv4_policy[];
 220 extern void             ip_fib_init(void);
 221 extern int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 222 extern int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 223 extern int inet_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 224 extern int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb);
 225 extern int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 226                                struct net_device *dev, __be32 *spec_dst, u32 *itag);
 227 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res);
 228
 229 struct rtentry;
 230
 231 /* Exported by fib_semantics.c */
 232 extern int ip_fib_check_default(u32 gw, struct net_device *dev);
 233 extern int fib_sync_down(u32 local, struct net_device *dev, int force);
 234 extern int fib_sync_up(struct net_device *dev);
 235 extern __be32  __fib_res_prefsrc(struct fib_result *res);
 236
 237 /* Exported by fib_hash.c */
 238 extern struct fib_table *fib_hash_init(u32 id);
 239
 240 #ifdef CONFIG_IP_MULTIPLE_TABLES
 241 extern int fib4_rules_dump(struct sk_buff *skb, struct netlink_callback *cb);
 242
 243 extern void __init fib4_rules_init(void);
 244
 245 #ifdef CONFIG_NET_CLS_ROUTE
 246 extern u32 fib_rules_tclass(struct fib_result *res);
 247 #endif
 248
 249 #endif
 250
 251 static inline void fib_combine_itag(u32 *itag, struct fib_result *res)
 252 {
 253 #ifdef CONFIG_NET_CLS_ROUTE
 254 #ifdef CONFIG_IP_MULTIPLE_TABLES
 255         u32 rtag;
 256 #endif
 257         *itag = FIB_RES_NH(*res).nh_tclassid<<16;
 258 #ifdef CONFIG_IP_MULTIPLE_TABLES
 259         rtag = fib_rules_tclass(res);
 260         if (*itag == 0)
 261                 *itag = (rtag<<16);
 262         *itag |= (rtag>>16);
 263 #endif
 264 #endif
 265 }
 266
 267 extern void free_fib_info(struct fib_info *fi);
 268
 269 static inline void fib_info_put(struct fib_info *fi)
 270 {
 271         if (atomic_dec_and_test(&fi->fib_clntref))
 272                 free_fib_info(fi);
 273 }
 274
 275 static inline void fib_res_put(struct fib_result *res)
 276 {
 277         if (res->fi)
 278                 fib_info_put(res->fi);
 279 #ifdef CONFIG_IP_MULTIPLE_TABLES
 280         if (res->r)
 281                 fib_rule_put(res->r);
 282 #endif
 283 }
 284
 285 #ifdef CONFIG_PROC_FS
 286 extern int  fib_proc_init(void);
 287 extern void fib_proc_exit(void);
 288 #endif
 289
 290 #endif  /* _NET_FIB_H */