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         int                     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 struct mx6_config {
  78         const u32 *mx;
  79         DECLARE_BITMAP(mx_valid, RTAX_MAX);
  80 };
  81
  82 /*
  83  *      routing information
  84  *
  85  */
  86
  87 struct rt6key {
  88         struct in6_addr addr;
  89         int             plen;
  90 };
  91
  92 struct fib6_table;
  93
  94 struct rt6_info {
  95         struct dst_entry                dst;
  96
  97         /*
  98          * Tail elements of dst_entry (__refcnt etc.)
  99          * and these elements (rarely used in hot path) are in
 100          * the same cache line.
 101          */
 102         struct fib6_table               *rt6i_table;
 103         struct fib6_node                *rt6i_node;
 104
 105         struct in6_addr                 rt6i_gateway;
 106
 107         /* Multipath routes:
 108          * siblings is a list of rt6_info that have the the same metric/weight,
 109          * destination, but not the same gateway. nsiblings is just a cache
 110          * to speed up lookup.
 111          */
 112         struct list_head                rt6i_siblings;
 113         unsigned int                    rt6i_nsiblings;
 114
 115         atomic_t                        rt6i_ref;
 116
 117         /* These are in a separate cache line. */
 118         struct rt6key                   rt6i_dst ____cacheline_aligned_in_smp;
 119         u32                             rt6i_flags;
 120         struct rt6key                   rt6i_src;
 121         struct rt6key                   rt6i_prefsrc;
 122
 123         struct inet6_dev                *rt6i_idev;
 124         unsigned long                   _rt6i_peer;
 125
 126         u32                             rt6i_metric;
 127         /* more non-fragment space at head required */
 128         unsigned short                  rt6i_nfheader_len;
 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         rt->rt6i_flags &= ~RTF_EXPIRES;
 170         rt->dst.expires = 0;
 171 }
 172
 173 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
 174 {
 175         rt->dst.expires = expires;
 176         rt->rt6i_flags |= RTF_EXPIRES;
 177 }
 178
 179 static inline void rt6_update_expires(struct rt6_info *rt0, int timeout)
 180 {
 181         struct rt6_info *rt;
 182
 183         for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES);
 184              rt = (struct rt6_info *)rt->dst.from);
 185         if (rt && rt != rt0)
 186                 rt0->dst.expires = rt->dst.expires;
 187
 188         dst_set_expires(&rt0->dst, timeout);
 189         rt0->rt6i_flags |= RTF_EXPIRES;
 190 }
 191
 192 static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
 193 {
 194         struct dst_entry *new = (struct dst_entry *) from;
 195
 196         rt->rt6i_flags &= ~RTF_EXPIRES;
 197         dst_hold(new);
 198         rt->dst.from = new;
 199 }
 200
 201 static inline void ip6_rt_put(struct rt6_info *rt)
 202 {
 203         /* dst_release() accepts a NULL parameter.
 204          * We rely on dst being first structure in struct rt6_info
 205          */
 206         BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
 207         dst_release(&rt->dst);
 208 }
 209
 210 enum fib6_walk_state {
 211 #ifdef CONFIG_IPV6_SUBTREES
 212         FWS_S,
 213 #endif
 214         FWS_L,
 215         FWS_R,
 216         FWS_C,
 217         FWS_U
 218 };
 219
 220 struct fib6_walker {
 221         struct list_head lh;
 222         struct fib6_node *root, *node;
 223         struct rt6_info *leaf;
 224         enum fib6_walk_state state;
 225         bool prune;
 226         unsigned int skip;
 227         unsigned int count;
 228         int (*func)(struct fib6_walker *);
 229         void *args;
 230 };
 231
 232 struct rt6_statistics {
 233         __u32           fib_nodes;
 234         __u32           fib_route_nodes;
 235         __u32           fib_rt_alloc;           /* permanent routes     */
 236         __u32           fib_rt_entries;         /* rt entries in table  */
 237         __u32           fib_rt_cache;           /* cache routes         */
 238         __u32           fib_discarded_routes;
 239 };
 240
 241 #define RTN_TL_ROOT     0x0001
 242 #define RTN_ROOT        0x0002          /* tree root node               */
 243 #define RTN_RTINFO      0x0004          /* node with valid routing info */
 244
 245 /*
 246  *      priority levels (or metrics)
 247  *
 248  */
 249
 250
 251 struct fib6_table {
 252         struct hlist_node       tb6_hlist;
 253         u32                     tb6_id;
 254         rwlock_t                tb6_lock;
 255         struct fib6_node        tb6_root;
 256         struct inet_peer_base   tb6_peers;
 257 };
 258
 259 #define RT6_TABLE_UNSPEC        RT_TABLE_UNSPEC
 260 #define RT6_TABLE_MAIN          RT_TABLE_MAIN
 261 #define RT6_TABLE_DFLT          RT6_TABLE_MAIN
 262 #define RT6_TABLE_INFO          RT6_TABLE_MAIN
 263 #define RT6_TABLE_PREFIX        RT6_TABLE_MAIN
 264
 265 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 266 #define FIB6_TABLE_MIN          1
 267 #define FIB6_TABLE_MAX          RT_TABLE_MAX
 268 #define RT6_TABLE_LOCAL         RT_TABLE_LOCAL
 269 #else
 270 #define FIB6_TABLE_MIN          RT_TABLE_MAIN
 271 #define FIB6_TABLE_MAX          FIB6_TABLE_MIN
 272 #define RT6_TABLE_LOCAL         RT6_TABLE_MAIN
 273 #endif
 274
 275 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
 276                                          struct fib6_table *,
 277                                          struct flowi6 *, int);
 278
 279 /*
 280  *      exported functions
 281  */
 282
 283 struct fib6_table *fib6_get_table(struct net *net, u32 id);
 284 struct fib6_table *fib6_new_table(struct net *net, u32 id);
 285 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
 286                                    int flags, pol_lookup_t lookup);
 287
 288 struct fib6_node *fib6_lookup(struct fib6_node *root,
 289                               const struct in6_addr *daddr,
 290                               const struct in6_addr *saddr);
 291
 292 struct fib6_node *fib6_locate(struct fib6_node *root,
 293                               const struct in6_addr *daddr, int dst_len,
 294                               const struct in6_addr *saddr, int src_len);
 295
 296 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
 297                     void *arg);
 298
 299 int fib6_add(struct fib6_node *root, struct rt6_info *rt,
 300              struct nl_info *info, struct mx6_config *mxc);
 301 int fib6_del(struct rt6_info *rt, struct nl_info *info);
 302
 303 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info);
 304
 305 void fib6_run_gc(unsigned long expires, struct net *net, bool force);
 306
 307 void fib6_gc_cleanup(void);
 308
 309 int fib6_init(void);
 310
 311 int ipv6_route_open(struct inode *inode, struct file *file);
 312
 313 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 314 int fib6_rules_init(void);
 315 void fib6_rules_cleanup(void);
 316 #else
 317 static inline int               fib6_rules_init(void)
 318 {
 319         return 0;
 320 }
 321 static inline void              fib6_rules_cleanup(void)
 322 {
 323         return ;
 324 }
 325 #endif
 326 #endif