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
  22 /* WARNING: The ordering of these elements must match ordering
  23  *          of RTA_* rtnetlink attribute numbers.
  24  */
  25 struct kern_rta {
  26         void            *rta_dst;
  27         void            *rta_src;
  28         int             *rta_iif;
  29         int             *rta_oif;
  30         void            *rta_gw;
  31         u32             *rta_priority;
  32         void            *rta_prefsrc;
  33         struct rtattr   *rta_mx;
  34         struct rtattr   *rta_mp;
  35         unsigned char   *rta_protoinfo;
  36         u32             *rta_flow;
  37         struct rta_cacheinfo *rta_ci;
  38         struct rta_session *rta_sess;
  39         u32             *rta_mp_alg;
  40 };
  41
  42 struct fib_info;
  43
  44 struct fib_nh {
  45         struct net_device       *nh_dev;
  46         struct hlist_node       nh_hash;
  47         struct fib_info         *nh_parent;
  48         unsigned                nh_flags;
  49         unsigned char           nh_scope;
  50 #ifdef CONFIG_IP_ROUTE_MULTIPATH
  51         int                     nh_weight;
  52         int                     nh_power;
  53 #endif
  54 #ifdef CONFIG_NET_CLS_ROUTE
  55         __u32                   nh_tclassid;
  56 #endif
  57         int                     nh_oif;
  58         u32                     nh_gw;
  59 };
  60
  61 /*
  62  * This structure contains data shared by many of routes.
  63  */
  64
  65 struct fib_info {
  66         struct hlist_node       fib_hash;
  67         struct hlist_node       fib_lhash;
  68         int                     fib_treeref;
  69         atomic_t                fib_clntref;
  70         int                     fib_dead;
  71         unsigned                fib_flags;
  72         int                     fib_protocol;
  73         u32                     fib_prefsrc;
  74         u32                     fib_priority;
  75         u32                     fib_metrics[RTAX_MAX];
  76 #define fib_mtu fib_metrics[RTAX_MTU-1]
  77 #define fib_window fib_metrics[RTAX_WINDOW-1]
  78 #define fib_rtt fib_metrics[RTAX_RTT-1]
  79 #define fib_advmss fib_metrics[RTAX_ADVMSS-1]
  80         int                     fib_nhs;
  81 #ifdef CONFIG_IP_ROUTE_MULTIPATH
  82         int                     fib_power;
  83 #endif
  84 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
  85         u32                     fib_mp_alg;
  86 #endif
  87         struct fib_nh           fib_nh[0];
  88 #define fib_dev         fib_nh[0].nh_dev
  89 };
  90
  91
  92 #ifdef CONFIG_IP_MULTIPLE_TABLES
  93 struct fib_rule;
  94 #endif
  95
  96 struct fib_result {
  97         unsigned char   prefixlen;
  98         unsigned char   nh_sel;
  99         unsigned char   type;
 100         unsigned char   scope;
 101 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
 102         __u32           network;
 103         __u32           netmask;
 104 #endif
 105         struct fib_info *fi;
 106 #ifdef CONFIG_IP_MULTIPLE_TABLES
 107         struct fib_rule *r;
 108 #endif
 109 };
 110
 111 struct fib_result_nl {
 112         u32             fl_addr;   /* To be looked up*/
 113         u32             fl_fwmark;
 114         unsigned char   fl_tos;
 115         unsigned char   fl_scope;
 116         unsigned char   tb_id_in;
 117
 118         unsigned char   tb_id;      /* Results */
 119         unsigned char   prefixlen;
 120         unsigned char   nh_sel;
 121         unsigned char   type;
 122         unsigned char   scope;
 123         int             err;
 124 };
 125
 126 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 127
 128 #define FIB_RES_NH(res)         ((res).fi->fib_nh[(res).nh_sel])
 129 #define FIB_RES_RESET(res)      ((res).nh_sel = 0)
 130
 131 #else /* CONFIG_IP_ROUTE_MULTIPATH */
 132
 133 #define FIB_RES_NH(res)         ((res).fi->fib_nh[0])
 134 #define FIB_RES_RESET(res)
 135
 136 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
 137
 138 #define FIB_RES_PREFSRC(res)            ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res))
 139 #define FIB_RES_GW(res)                 (FIB_RES_NH(res).nh_gw)
 140 #define FIB_RES_DEV(res)                (FIB_RES_NH(res).nh_dev)
 141 #define FIB_RES_OIF(res)                (FIB_RES_NH(res).nh_oif)
 142
 143 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
 144 #define FIB_RES_NETWORK(res)            ((res).network)
 145 #define FIB_RES_NETMASK(res)            ((res).netmask)
 146 #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */
 147 #define FIB_RES_NETWORK(res)            (0)
 148 #define FIB_RES_NETMASK(res)            (0)
 149 #endif /* CONFIG_IP_ROUTE_MULTIPATH_WRANDOM */
 150
 151 struct fib_table {
 152         unsigned char   tb_id;
 153         unsigned        tb_stamp;
 154         int             (*tb_lookup)(struct fib_table *tb, const struct flowi *flp, struct fib_result *res);
 155         int             (*tb_insert)(struct fib_table *table, struct rtmsg *r,
 156                                      struct kern_rta *rta, struct nlmsghdr *n,
 157                                      struct netlink_skb_parms *req);
 158         int             (*tb_delete)(struct fib_table *table, struct rtmsg *r,
 159                                      struct kern_rta *rta, struct nlmsghdr *n,
 160                                      struct netlink_skb_parms *req);
 161         int             (*tb_dump)(struct fib_table *table, struct sk_buff *skb,
 162                                      struct netlink_callback *cb);
 163         int             (*tb_flush)(struct fib_table *table);
 164         void            (*tb_select_default)(struct fib_table *table,
 165                                              const struct flowi *flp, struct fib_result *res);
 166
 167         unsigned char   tb_data[0];
 168 };
 169
 170 #ifndef CONFIG_IP_MULTIPLE_TABLES
 171
 172 extern struct fib_table *ip_fib_local_table;
 173 extern struct fib_table *ip_fib_main_table;
 174
 175 static inline struct fib_table *fib_get_table(int id)
 176 {
 177         if (id != RT_TABLE_LOCAL)
 178                 return ip_fib_main_table;
 179         return ip_fib_local_table;
 180 }
 181
 182 static inline struct fib_table *fib_new_table(int id)
 183 {
 184         return fib_get_table(id);
 185 }
 186
 187 static inline int fib_lookup(const struct flowi *flp, struct fib_result *res)
 188 {
 189         if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) &&
 190             ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res))
 191                 return -ENETUNREACH;
 192         return 0;
 193 }
 194
 195 static inline void fib_select_default(const struct flowi *flp, struct fib_result *res)
 196 {
 197         if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
 198                 ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res);
 199 }
 200
 201 #else /* CONFIG_IP_MULTIPLE_TABLES */
 202 #define ip_fib_local_table (fib_tables[RT_TABLE_LOCAL])
 203 #define ip_fib_main_table (fib_tables[RT_TABLE_MAIN])
 204
 205 extern struct fib_table * fib_tables[RT_TABLE_MAX+1];
 206 extern int fib_lookup(const struct flowi *flp, struct fib_result *res);
 207 extern struct fib_table *__fib_new_table(int id);
 208 extern void fib_rule_put(struct fib_rule *r);
 209
 210 static inline struct fib_table *fib_get_table(int id)
 211 {
 212         if (id == 0)
 213                 id = RT_TABLE_MAIN;
 214
 215         return fib_tables[id];
 216 }
 217
 218 static inline struct fib_table *fib_new_table(int id)
 219 {
 220         if (id == 0)
 221                 id = RT_TABLE_MAIN;
 222
 223         return fib_tables[id] ? : __fib_new_table(id);
 224 }
 225
 226 extern void fib_select_default(const struct flowi *flp, struct fib_result *res);
 227
 228 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 229
 230 /* Exported by fib_frontend.c */
 231 extern void             ip_fib_init(void);
 232 extern int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 233 extern int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 234 extern int inet_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 235 extern int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb);
 236 extern int fib_validate_source(u32 src, u32 dst, u8 tos, int oif,
 237                                struct net_device *dev, u32 *spec_dst, u32 *itag);
 238 extern void fib_select_multipath(const struct flowi *flp, struct fib_result *res);
 239
 240 struct rtentry;
 241
 242 /* Exported by fib_semantics.c */
 243 extern int ip_fib_check_default(u32 gw, struct net_device *dev);
 244 extern int fib_sync_down(u32 local, struct net_device *dev, int force);
 245 extern int fib_sync_up(struct net_device *dev);
 246 extern int fib_convert_rtentry(int cmd, struct nlmsghdr *nl, struct rtmsg *rtm,
 247                                struct kern_rta *rta, struct rtentry *r);
 248 extern u32  __fib_res_prefsrc(struct fib_result *res);
 249
 250 /* Exported by fib_hash.c */
 251 extern struct fib_table *fib_hash_init(int id);
 252
 253 #ifdef CONFIG_IP_MULTIPLE_TABLES
 254 /* Exported by fib_rules.c */
 255
 256 extern int inet_rtm_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 257 extern int inet_rtm_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 258 extern int inet_dump_rules(struct sk_buff *skb, struct netlink_callback *cb);
 259 #ifdef CONFIG_NET_CLS_ROUTE
 260 extern u32 fib_rules_tclass(struct fib_result *res);
 261 #endif
 262 extern void fib_rules_init(void);
 263 #endif
 264
 265 static inline void fib_combine_itag(u32 *itag, struct fib_result *res)
 266 {
 267 #ifdef CONFIG_NET_CLS_ROUTE
 268 #ifdef CONFIG_IP_MULTIPLE_TABLES
 269         u32 rtag;
 270 #endif
 271         *itag = FIB_RES_NH(*res).nh_tclassid<<16;
 272 #ifdef CONFIG_IP_MULTIPLE_TABLES
 273         rtag = fib_rules_tclass(res);
 274         if (*itag == 0)
 275                 *itag = (rtag<<16);
 276         *itag |= (rtag>>16);
 277 #endif
 278 #endif
 279 }
 280
 281 extern void free_fib_info(struct fib_info *fi);
 282
 283 static inline void fib_info_put(struct fib_info *fi)
 284 {
 285         if (atomic_dec_and_test(&fi->fib_clntref))
 286                 free_fib_info(fi);
 287 }
 288
 289 static inline void fib_res_put(struct fib_result *res)
 290 {
 291         if (res->fi)
 292                 fib_info_put(res->fi);
 293 #ifdef CONFIG_IP_MULTIPLE_TABLES
 294         if (res->r)
 295                 fib_rule_put(res->r);
 296 #endif
 297 }
 298
 299 #ifdef CONFIG_PROC_FS
 300 extern int  fib_proc_init(void);
 301 extern void fib_proc_exit(void);
 302 #endif
 303
 304 #endif  /* _NET_FIB_H */