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