include/net/ip6_fib.h

   1 /*
   2  *      Linux INET6 implementation
   3  *
   4  *      Authors:
   5  *      Pedro Roque             <roque@di.fc.ul.pt>
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License
   9  *      as published by the Free Software Foundation; either version
  10  *      2 of the License, or (at your option) any later version.
  11  */
  12
  13 #ifndef _IP6_FIB_H
  14 #define _IP6_FIB_H
  15
  16 #include <linux/ipv6_route.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/spinlock.h>
  19 #include <net/dst.h>
  20 #include <net/flow.h>
  21 #include <net/netlink.h>
  22 #include <net/inetpeer.h>
  23
  24 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
  25 #define FIB6_TABLE_HASHSZ 256
  26 #else
  27 #define FIB6_TABLE_HASHSZ 1
  28 #endif
  29
  30 struct rt6_info;
  31
  32 struct fib6_config {
  33         u32             fc_table;
  34         u32             fc_metric;
  35         int             fc_dst_len;
  36         int             fc_src_len;
  37         int             fc_ifindex;
  38         u32             fc_flags;
  39         u32             fc_protocol;
  40
  41         struct in6_addr fc_dst;
  42         struct in6_addr fc_src;
  43         struct in6_addr fc_prefsrc;
  44         struct in6_addr fc_gateway;
  45
  46         unsigned long   fc_expires;
  47         struct nlattr   *fc_mx;
  48         int             fc_mx_len;
  49
  50         struct nl_info  fc_nlinfo;
  51 };
  52
  53 struct fib6_node {
  54         struct fib6_node        *parent;
  55         struct fib6_node        *left;
  56         struct fib6_node        *right;
  57 #ifdef CONFIG_IPV6_SUBTREES
  58         struct fib6_node        *subtree;
  59 #endif
  60         struct rt6_info         *leaf;
  61
  62         __u16                   fn_bit;         /* bit key */
  63         __u16                   fn_flags;
  64         __u32                   fn_sernum;
  65         struct rt6_info         *rr_ptr;
  66 };
  67
  68 #ifndef CONFIG_IPV6_SUBTREES
  69 #define FIB6_SUBTREE(fn)        NULL
  70 #else
  71 #define FIB6_SUBTREE(fn)        ((fn)->subtree)
  72 #endif
  73
  74 /*
  75  *      routing information
  76  *
  77  */
  78
  79 struct rt6key {
  80         struct in6_addr addr;
  81         int             plen;
  82 };
  83
  84 struct fib6_table;
  85
  86 struct rt6_info {
  87         struct dst_entry                dst;
  88
  89         /*
  90          * Tail elements of dst_entry (__refcnt etc.)
  91          * and these elements (rarely used in hot path) are in
  92          * the same cache line.
  93          */
  94         struct fib6_table               *rt6i_table;
  95         struct fib6_node                *rt6i_node;
  96
  97         struct in6_addr                 rt6i_gateway;
  98
  99         atomic_t                        rt6i_ref;
 100
 101         /* These are in a separate cache line. */
 102         struct rt6key                   rt6i_dst ____cacheline_aligned_in_smp;
 103         u32                             rt6i_flags;
 104         struct rt6key                   rt6i_src;
 105         struct rt6key                   rt6i_prefsrc;
 106         u32                             rt6i_metric;
 107         u32                             rt6i_peer_genid;
 108
 109         struct inet6_dev                *rt6i_idev;
 110         struct inet_peer                *rt6i_peer;
 111
 112 #ifdef CONFIG_XFRM
 113         u32                             rt6i_flow_cache_genid;
 114 #endif
 115         /* more non-fragment space at head required */
 116         unsigned short                  rt6i_nfheader_len;
 117
 118         u8                              rt6i_protocol;
 119 };
 120
 121 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
 122 {
 123         return ((struct rt6_info *)dst)->rt6i_idev;
 124 }
 125
 126 static inline void rt6_clean_expires(struct rt6_info *rt)
 127 {
 128         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
 129                 dst_release(rt->dst.from);
 130
 131         rt->rt6i_flags &= ~RTF_EXPIRES;
 132         rt->dst.expires = 0;
 133 }
 134
 135 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
 136 {
 137         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
 138                 dst_release(rt->dst.from);
 139
 140         rt->rt6i_flags |= RTF_EXPIRES;
 141         rt->dst.expires = expires;
 142 }
 143
 144 static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
 145 {
 146         if (!(rt->rt6i_flags & RTF_EXPIRES)) {
 147                 if (rt->dst.from)
 148                         dst_release(rt->dst.from);
 149                 /* dst_set_expires relies on expires == 0
 150                  * if it has not been set previously.
 151                  */
 152                 rt->dst.expires = 0;
 153         }
 154
 155         dst_set_expires(&rt->dst, timeout);
 156         rt->rt6i_flags |= RTF_EXPIRES;
 157 }
 158
 159 static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
 160 {
 161         struct dst_entry *new = (struct dst_entry *) from;
 162
 163         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from) {
 164                 if (new == rt->dst.from)
 165                         return;
 166                 dst_release(rt->dst.from);
 167         }
 168
 169         rt->rt6i_flags &= ~RTF_EXPIRES;
 170         rt->dst.from = new;
 171         dst_hold(new);
 172 }
 173
 174 struct fib6_walker_t {
 175         struct list_head lh;
 176         struct fib6_node *root, *node;
 177         struct rt6_info *leaf;
 178         unsigned char state;
 179         unsigned char prune;
 180         unsigned int skip;
 181         unsigned int count;
 182         int (*func)(struct fib6_walker_t *);
 183         void *args;
 184 };
 185
 186 struct rt6_statistics {
 187         __u32           fib_nodes;
 188         __u32           fib_route_nodes;
 189         __u32           fib_rt_alloc;           /* permanent routes     */
 190         __u32           fib_rt_entries;         /* rt entries in table  */
 191         __u32           fib_rt_cache;           /* cache routes         */
 192         __u32           fib_discarded_routes;
 193 };
 194
 195 #define RTN_TL_ROOT     0x0001
 196 #define RTN_ROOT        0x0002          /* tree root node               */
 197 #define RTN_RTINFO      0x0004          /* node with valid routing info */
 198
 199 /*
 200  *      priority levels (or metrics)
 201  *
 202  */
 203
 204
 205 struct fib6_table {
 206         struct hlist_node       tb6_hlist;
 207         u32                     tb6_id;
 208         rwlock_t                tb6_lock;
 209         struct fib6_node        tb6_root;
 210 };
 211
 212 #define RT6_TABLE_UNSPEC        RT_TABLE_UNSPEC
 213 #define RT6_TABLE_MAIN          RT_TABLE_MAIN
 214 #define RT6_TABLE_DFLT          RT6_TABLE_MAIN
 215 #define RT6_TABLE_INFO          RT6_TABLE_MAIN
 216 #define RT6_TABLE_PREFIX        RT6_TABLE_MAIN
 217
 218 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 219 #define FIB6_TABLE_MIN          1
 220 #define FIB6_TABLE_MAX          RT_TABLE_MAX
 221 #define RT6_TABLE_LOCAL         RT_TABLE_LOCAL
 222 #else
 223 #define FIB6_TABLE_MIN          RT_TABLE_MAIN
 224 #define FIB6_TABLE_MAX          FIB6_TABLE_MIN
 225 #define RT6_TABLE_LOCAL         RT6_TABLE_MAIN
 226 #endif
 227
 228 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
 229                                          struct fib6_table *,
 230                                          struct flowi6 *, int);
 231
 232 /*
 233  *      exported functions
 234  */
 235
 236 extern struct fib6_table        *fib6_get_table(struct net *net, u32 id);
 237 extern struct fib6_table        *fib6_new_table(struct net *net, u32 id);
 238 extern struct dst_entry         *fib6_rule_lookup(struct net *net,
 239                                                   struct flowi6 *fl6, int flags,
 240                                                   pol_lookup_t lookup);
 241
 242 extern struct fib6_node         *fib6_lookup(struct fib6_node *root,
 243                                              const struct in6_addr *daddr,
 244                                              const struct in6_addr *saddr);
 245
 246 struct fib6_node                *fib6_locate(struct fib6_node *root,
 247                                              const struct in6_addr *daddr, int dst_len,
 248                                              const struct in6_addr *saddr, int src_len);
 249
 250 extern void                     fib6_clean_all_ro(struct net *net,
 251                                                int (*func)(struct rt6_info *, void *arg),
 252                                                int prune, void *arg);
 253
 254 extern void                     fib6_clean_all(struct net *net,
 255                                                int (*func)(struct rt6_info *, void *arg),
 256                                                int prune, void *arg);
 257
 258 extern int                      fib6_add(struct fib6_node *root,
 259                                          struct rt6_info *rt,
 260                                          struct nl_info *info);
 261
 262 extern int                      fib6_del(struct rt6_info *rt,
 263                                          struct nl_info *info);
 264
 265 extern void                     inet6_rt_notify(int event, struct rt6_info *rt,
 266                                                 struct nl_info *info);
 267
 268 extern void                     fib6_run_gc(unsigned long expires,
 269                                             struct net *net);
 270
 271 extern void                     fib6_gc_cleanup(void);
 272
 273 extern int                      fib6_init(void);
 274
 275 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 276 extern int                      fib6_rules_init(void);
 277 extern void                     fib6_rules_cleanup(void);
 278 #else
 279 static inline int               fib6_rules_init(void)
 280 {
 281         return 0;
 282 }
 283 static inline void              fib6_rules_cleanup(void)
 284 {
 285         return ;
 286 }
 287 #endif
 288 #endif