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 /*
  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
 118         struct inet6_dev                *rt6i_idev;
 119         unsigned long                   _rt6i_peer;
 120
 121         u32                             rt6i_metric;
 122         /* more non-fragment space at head required */
 123         unsigned short                  rt6i_nfheader_len;
 124         u8                              rt6i_protocol;
 125 };
 126
 127 static inline struct inet_peer *rt6_peer_ptr(struct rt6_info *rt)
 128 {
 129         return inetpeer_ptr(rt->_rt6i_peer);
 130 }
 131
 132 static inline bool rt6_has_peer(struct rt6_info *rt)
 133 {
 134         return inetpeer_ptr_is_peer(rt->_rt6i_peer);
 135 }
 136
 137 static inline void __rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
 138 {
 139         __inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
 140 }
 141
 142 static inline bool rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
 143 {
 144         return inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
 145 }
 146
 147 static inline void rt6_init_peer(struct rt6_info *rt, struct inet_peer_base *base)
 148 {
 149         inetpeer_init_ptr(&rt->_rt6i_peer, base);
 150 }
 151
 152 static inline void rt6_transfer_peer(struct rt6_info *rt, struct rt6_info *ort)
 153 {
 154         inetpeer_transfer_peer(&rt->_rt6i_peer, &ort->_rt6i_peer);
 155 }
 156
 157 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
 158 {
 159         return ((struct rt6_info *)dst)->rt6i_idev;
 160 }
 161
 162 static inline void rt6_clean_expires(struct rt6_info *rt)
 163 {
 164         rt->rt6i_flags &= ~RTF_EXPIRES;
 165         rt->dst.expires = 0;
 166 }
 167
 168 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
 169 {
 170         rt->dst.expires = expires;
 171         rt->rt6i_flags |= RTF_EXPIRES;
 172 }
 173
 174 static inline void rt6_update_expires(struct rt6_info *rt0, int timeout)
 175 {
 176         struct rt6_info *rt;
 177
 178         for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES);
 179              rt = (struct rt6_info *)rt->dst.from);
 180         if (rt && rt != rt0)
 181                 rt0->dst.expires = rt->dst.expires;
 182
 183         dst_set_expires(&rt0->dst, timeout);
 184         rt0->rt6i_flags |= RTF_EXPIRES;
 185 }
 186
 187 static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
 188 {
 189         struct dst_entry *new = (struct dst_entry *) from;
 190
 191         rt->rt6i_flags &= ~RTF_EXPIRES;
 192         dst_hold(new);
 193         rt->dst.from = new;
 194 }
 195
 196 static inline void ip6_rt_put(struct rt6_info *rt)
 197 {
 198         /* dst_release() accepts a NULL parameter.
 199          * We rely on dst being first structure in struct rt6_info
 200          */
 201         BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
 202         dst_release(&rt->dst);
 203 }
 204
 205 enum fib6_walk_state {
 206 #ifdef CONFIG_IPV6_SUBTREES
 207         FWS_S,
 208 #endif
 209         FWS_L,
 210         FWS_R,
 211         FWS_C,
 212         FWS_U
 213 };
 214
 215 struct fib6_walker {
 216         struct list_head lh;
 217         struct fib6_node *root, *node;
 218         struct rt6_info *leaf;
 219         enum fib6_walk_state state;
 220         bool prune;
 221         unsigned int skip;
 222         unsigned int count;
 223         int (*func)(struct fib6_walker *);
 224         void *args;
 225 };
 226
 227 struct rt6_statistics {
 228         __u32           fib_nodes;
 229         __u32           fib_route_nodes;
 230         __u32           fib_rt_alloc;           /* permanent routes     */
 231         __u32           fib_rt_entries;         /* rt entries in table  */
 232         __u32           fib_rt_cache;           /* cache routes         */
 233         __u32           fib_discarded_routes;
 234 };
 235
 236 #define RTN_TL_ROOT     0x0001
 237 #define RTN_ROOT        0x0002          /* tree root node               */
 238 #define RTN_RTINFO      0x0004          /* node with valid routing info */
 239
 240 /*
 241  *      priority levels (or metrics)
 242  *
 243  */
 244
 245
 246 struct fib6_table {
 247         struct hlist_node       tb6_hlist;
 248         u32                     tb6_id;
 249         rwlock_t                tb6_lock;
 250         struct fib6_node        tb6_root;
 251         struct inet_peer_base   tb6_peers;
 252 };
 253
 254 #define RT6_TABLE_UNSPEC        RT_TABLE_UNSPEC
 255 #define RT6_TABLE_MAIN          RT_TABLE_MAIN
 256 #define RT6_TABLE_DFLT          RT6_TABLE_MAIN
 257 #define RT6_TABLE_INFO          RT6_TABLE_MAIN
 258 #define RT6_TABLE_PREFIX        RT6_TABLE_MAIN
 259
 260 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 261 #define FIB6_TABLE_MIN          1
 262 #define FIB6_TABLE_MAX          RT_TABLE_MAX
 263 #define RT6_TABLE_LOCAL         RT_TABLE_LOCAL
 264 #else
 265 #define FIB6_TABLE_MIN          RT_TABLE_MAIN
 266 #define FIB6_TABLE_MAX          FIB6_TABLE_MIN
 267 #define RT6_TABLE_LOCAL         RT6_TABLE_MAIN
 268 #endif
 269
 270 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
 271                                          struct fib6_table *,
 272                                          struct flowi6 *, int);
 273
 274 /*
 275  *      exported functions
 276  */
 277
 278 struct fib6_table *fib6_get_table(struct net *net, u32 id);
 279 struct fib6_table *fib6_new_table(struct net *net, u32 id);
 280 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
 281                                    int flags, pol_lookup_t lookup);
 282
 283 struct fib6_node *fib6_lookup(struct fib6_node *root,
 284                               const struct in6_addr *daddr,
 285                               const struct in6_addr *saddr);
 286
 287 struct fib6_node *fib6_locate(struct fib6_node *root,
 288                               const struct in6_addr *daddr, int dst_len,
 289                               const struct in6_addr *saddr, int src_len);
 290
 291 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
 292                     void *arg);
 293
 294 int fib6_add(struct fib6_node *root, struct rt6_info *rt, struct nl_info *info,
 295              struct nlattr *mx, int mx_len);
 296
 297 int fib6_del(struct rt6_info *rt, struct nl_info *info);
 298
 299 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info);
 300
 301 void fib6_run_gc(unsigned long expires, struct net *net, bool force);
 302
 303 void fib6_gc_cleanup(void);
 304
 305 int fib6_init(void);
 306
 307 int ipv6_route_open(struct inode *inode, struct file *file);
 308
 309 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 310 int fib6_rules_init(void);
 311 void fib6_rules_cleanup(void);
 312 #else
 313 static inline int               fib6_rules_init(void)
 314 {
 315         return 0;
 316 }
 317 static inline void              fib6_rules_cleanup(void)
 318 {
 319         return ;
 320 }
 321 #endif
 322 #endif