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         u32             fc_type;        /* only 8 bits are used */
  41
  42         struct in6_addr fc_dst;
  43         struct in6_addr fc_src;
  44         struct in6_addr fc_prefsrc;
  45         struct in6_addr fc_gateway;
  46
  47         unsigned long   fc_expires;
  48         struct nlattr   *fc_mx;
  49         int             fc_mx_len;
  50         int             fc_mp_len;
  51         struct nlattr   *fc_mp;
  52
  53         struct nl_info  fc_nlinfo;
  54 };
  55
  56 struct fib6_node {
  57         struct fib6_node        *parent;
  58         struct fib6_node        *left;
  59         struct fib6_node        *right;
  60 #ifdef CONFIG_IPV6_SUBTREES
  61         struct fib6_node        *subtree;
  62 #endif
  63         struct rt6_info         *leaf;
  64
  65         __u16                   fn_bit;         /* bit key */
  66         __u16                   fn_flags;
  67         __u32                   fn_sernum;
  68         struct rt6_info         *rr_ptr;
  69 };
  70
  71 #ifndef CONFIG_IPV6_SUBTREES
  72 #define FIB6_SUBTREE(fn)        NULL
  73 #else
  74 #define FIB6_SUBTREE(fn)        ((fn)->subtree)
  75 #endif
  76
  77 /*
  78  *      routing information
  79  *
  80  */
  81
  82 struct rt6key {
  83         struct in6_addr addr;
  84         int             plen;
  85 };
  86
  87 struct fib6_table;
  88
  89 struct rt6_info {
  90         struct dst_entry                dst;
  91
  92         struct neighbour                *n;
  93
  94         /*
  95          * Tail elements of dst_entry (__refcnt etc.)
  96          * and these elements (rarely used in hot path) are in
  97          * the same cache line.
  98          */
  99         struct fib6_table               *rt6i_table;
 100         struct fib6_node                *rt6i_node;
 101
 102         struct in6_addr                 rt6i_gateway;
 103
 104         /* Multipath routes:
 105          * siblings is a list of rt6_info that have the the same metric/weight,
 106          * destination, but not the same gateway. nsiblings is just a cache
 107          * to speed up lookup.
 108          */
 109         struct list_head                rt6i_siblings;
 110         unsigned int                    rt6i_nsiblings;
 111
 112         atomic_t                        rt6i_ref;
 113
 114         /* These are in a separate cache line. */
 115         struct rt6key                   rt6i_dst ____cacheline_aligned_in_smp;
 116         u32                             rt6i_flags;
 117         struct rt6key                   rt6i_src;
 118         struct rt6key                   rt6i_prefsrc;
 119         u32                             rt6i_metric;
 120
 121         struct inet6_dev                *rt6i_idev;
 122         unsigned long                   _rt6i_peer;
 123
 124         u32                             rt6i_genid;
 125
 126         /* more non-fragment space at head required */
 127         unsigned short                  rt6i_nfheader_len;
 128
 129         u8                              rt6i_protocol;
 130 };
 131
 132 static inline struct inet_peer *rt6_peer_ptr(struct rt6_info *rt)
 133 {
 134         return inetpeer_ptr(rt->_rt6i_peer);
 135 }
 136
 137 static inline bool rt6_has_peer(struct rt6_info *rt)
 138 {
 139         return inetpeer_ptr_is_peer(rt->_rt6i_peer);
 140 }
 141
 142 static inline void __rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
 143 {
 144         __inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
 145 }
 146
 147 static inline bool rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
 148 {
 149         return inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
 150 }
 151
 152 static inline void rt6_init_peer(struct rt6_info *rt, struct inet_peer_base *base)
 153 {
 154         inetpeer_init_ptr(&rt->_rt6i_peer, base);
 155 }
 156
 157 static inline void rt6_transfer_peer(struct rt6_info *rt, struct rt6_info *ort)
 158 {
 159         inetpeer_transfer_peer(&rt->_rt6i_peer, &ort->_rt6i_peer);
 160 }
 161
 162 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
 163 {
 164         return ((struct rt6_info *)dst)->rt6i_idev;
 165 }
 166
 167 static inline void rt6_clean_expires(struct rt6_info *rt)
 168 {
 169         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
 170                 dst_release(rt->dst.from);
 171
 172         rt->rt6i_flags &= ~RTF_EXPIRES;
 173         rt->dst.from = NULL;
 174 }
 175
 176 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
 177 {
 178         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
 179                 dst_release(rt->dst.from);
 180
 181         rt->rt6i_flags |= RTF_EXPIRES;
 182         rt->dst.expires = expires;
 183 }
 184
 185 static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
 186 {
 187         if (!(rt->rt6i_flags & RTF_EXPIRES)) {
 188                 if (rt->dst.from)
 189                         dst_release(rt->dst.from);
 190                 /* dst_set_expires relies on expires == 0
 191                  * if it has not been set previously.
 192                  */
 193                 rt->dst.expires = 0;
 194         }
 195
 196         dst_set_expires(&rt->dst, timeout);
 197         rt->rt6i_flags |= RTF_EXPIRES;
 198 }
 199
 200 static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
 201 {
 202         struct dst_entry *new = (struct dst_entry *) from;
 203
 204         if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from) {
 205                 if (new == rt->dst.from)
 206                         return;
 207                 dst_release(rt->dst.from);
 208         }
 209
 210         rt->rt6i_flags &= ~RTF_EXPIRES;
 211         rt->dst.from = new;
 212         dst_hold(new);
 213 }
 214
 215 static inline void ip6_rt_put(struct rt6_info *rt)
 216 {
 217         /* dst_release() accepts a NULL parameter.
 218          * We rely on dst being first structure in struct rt6_info
 219          */
 220         BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
 221         dst_release(&rt->dst);
 222 }
 223
 224 struct fib6_walker_t {
 225         struct list_head lh;
 226         struct fib6_node *root, *node;
 227         struct rt6_info *leaf;
 228         unsigned char state;
 229         unsigned char prune;
 230         unsigned int skip;
 231         unsigned int count;
 232         int (*func)(struct fib6_walker_t *);
 233         void *args;
 234 };
 235
 236 struct rt6_statistics {
 237         __u32           fib_nodes;
 238         __u32           fib_route_nodes;
 239         __u32           fib_rt_alloc;           /* permanent routes     */
 240         __u32           fib_rt_entries;         /* rt entries in table  */
 241         __u32           fib_rt_cache;           /* cache routes         */
 242         __u32           fib_discarded_routes;
 243 };
 244
 245 #define RTN_TL_ROOT     0x0001
 246 #define RTN_ROOT        0x0002          /* tree root node               */
 247 #define RTN_RTINFO      0x0004          /* node with valid routing info */
 248
 249 /*
 250  *      priority levels (or metrics)
 251  *
 252  */
 253
 254
 255 struct fib6_table {
 256         struct hlist_node       tb6_hlist;
 257         u32                     tb6_id;
 258         rwlock_t                tb6_lock;
 259         struct fib6_node        tb6_root;
 260         struct inet_peer_base   tb6_peers;
 261 };
 262
 263 #define RT6_TABLE_UNSPEC        RT_TABLE_UNSPEC
 264 #define RT6_TABLE_MAIN          RT_TABLE_MAIN
 265 #define RT6_TABLE_DFLT          RT6_TABLE_MAIN
 266 #define RT6_TABLE_INFO          RT6_TABLE_MAIN
 267 #define RT6_TABLE_PREFIX        RT6_TABLE_MAIN
 268
 269 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 270 #define FIB6_TABLE_MIN          1
 271 #define FIB6_TABLE_MAX          RT_TABLE_MAX
 272 #define RT6_TABLE_LOCAL         RT_TABLE_LOCAL
 273 #else
 274 #define FIB6_TABLE_MIN          RT_TABLE_MAIN
 275 #define FIB6_TABLE_MAX          FIB6_TABLE_MIN
 276 #define RT6_TABLE_LOCAL         RT6_TABLE_MAIN
 277 #endif
 278
 279 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
 280                                          struct fib6_table *,
 281                                          struct flowi6 *, int);
 282
 283 /*
 284  *      exported functions
 285  */
 286
 287 extern struct fib6_table        *fib6_get_table(struct net *net, u32 id);
 288 extern struct fib6_table        *fib6_new_table(struct net *net, u32 id);
 289 extern struct dst_entry         *fib6_rule_lookup(struct net *net,
 290                                                   struct flowi6 *fl6, int flags,
 291                                                   pol_lookup_t lookup);
 292
 293 extern struct fib6_node         *fib6_lookup(struct fib6_node *root,
 294                                              const struct in6_addr *daddr,
 295                                              const struct in6_addr *saddr);
 296
 297 struct fib6_node                *fib6_locate(struct fib6_node *root,
 298                                              const struct in6_addr *daddr, int dst_len,
 299                                              const struct in6_addr *saddr, int src_len);
 300
 301 extern void                     fib6_clean_all_ro(struct net *net,
 302                                                int (*func)(struct rt6_info *, void *arg),
 303                                                int prune, void *arg);
 304
 305 extern void                     fib6_clean_all(struct net *net,
 306                                                int (*func)(struct rt6_info *, void *arg),
 307                                                int prune, void *arg);
 308
 309 extern int                      fib6_add(struct fib6_node *root,
 310                                          struct rt6_info *rt,
 311                                          struct nl_info *info);
 312
 313 extern int                      fib6_del(struct rt6_info *rt,
 314                                          struct nl_info *info);
 315
 316 extern void                     inet6_rt_notify(int event, struct rt6_info *rt,
 317                                                 struct nl_info *info);
 318
 319 extern void                     fib6_run_gc(unsigned long expires,
 320                                             struct net *net);
 321
 322 extern void                     fib6_gc_cleanup(void);
 323
 324 extern int                      fib6_init(void);
 325
 326 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 327 extern int                      fib6_rules_init(void);
 328 extern void                     fib6_rules_cleanup(void);
 329 #else
 330 static inline int               fib6_rules_init(void)
 331 {
 332         return 0;
 333 }
 334 static inline void              fib6_rules_cleanup(void)
 335 {
 336         return ;
 337 }
 338 #endif
 339 #endif