xref: /linux/include/net/ip6_fib.h (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
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 	struct neighbour		*n;
90 
91 	/*
92 	 * Tail elements of dst_entry (__refcnt etc.)
93 	 * and these elements (rarely used in hot path) are in
94 	 * the same cache line.
95 	 */
96 	struct fib6_table		*rt6i_table;
97 	struct fib6_node		*rt6i_node;
98 
99 	struct in6_addr			rt6i_gateway;
100 
101 	atomic_t			rt6i_ref;
102 
103 	/* These are in a separate cache line. */
104 	struct rt6key			rt6i_dst ____cacheline_aligned_in_smp;
105 	u32				rt6i_flags;
106 	struct rt6key			rt6i_src;
107 	struct rt6key			rt6i_prefsrc;
108 	u32				rt6i_metric;
109 	u32				rt6i_peer_genid;
110 
111 	struct inet6_dev		*rt6i_idev;
112 	unsigned long			_rt6i_peer;
113 
114 #ifdef CONFIG_XFRM
115 	u32				rt6i_flow_cache_genid;
116 #endif
117 	/* more non-fragment space at head required */
118 	unsigned short			rt6i_nfheader_len;
119 
120 	u8				rt6i_protocol;
121 };
122 
123 static inline struct inet_peer *rt6_peer_ptr(struct rt6_info *rt)
124 {
125 	return inetpeer_ptr(rt->_rt6i_peer);
126 }
127 
128 static inline bool rt6_has_peer(struct rt6_info *rt)
129 {
130 	return inetpeer_ptr_is_peer(rt->_rt6i_peer);
131 }
132 
133 static inline void __rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
134 {
135 	__inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
136 }
137 
138 static inline bool rt6_set_peer(struct rt6_info *rt, struct inet_peer *peer)
139 {
140 	return inetpeer_ptr_set_peer(&rt->_rt6i_peer, peer);
141 }
142 
143 static inline void rt6_init_peer(struct rt6_info *rt, struct inet_peer_base *base)
144 {
145 	inetpeer_init_ptr(&rt->_rt6i_peer, base);
146 }
147 
148 static inline void rt6_transfer_peer(struct rt6_info *rt, struct rt6_info *ort)
149 {
150 	inetpeer_transfer_peer(&rt->_rt6i_peer, &ort->_rt6i_peer);
151 }
152 
153 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
154 {
155 	return ((struct rt6_info *)dst)->rt6i_idev;
156 }
157 
158 static inline void rt6_clean_expires(struct rt6_info *rt)
159 {
160 	if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
161 		dst_release(rt->dst.from);
162 
163 	rt->rt6i_flags &= ~RTF_EXPIRES;
164 	rt->dst.from = NULL;
165 }
166 
167 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
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.expires = expires;
174 }
175 
176 static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
177 {
178 	if (!(rt->rt6i_flags & RTF_EXPIRES)) {
179 		if (rt->dst.from)
180 			dst_release(rt->dst.from);
181 		/* dst_set_expires relies on expires == 0
182 		 * if it has not been set previously.
183 		 */
184 		rt->dst.expires = 0;
185 	}
186 
187 	dst_set_expires(&rt->dst, timeout);
188 	rt->rt6i_flags |= RTF_EXPIRES;
189 }
190 
191 static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
192 {
193 	struct dst_entry *new = (struct dst_entry *) from;
194 
195 	if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from) {
196 		if (new == rt->dst.from)
197 			return;
198 		dst_release(rt->dst.from);
199 	}
200 
201 	rt->rt6i_flags &= ~RTF_EXPIRES;
202 	rt->dst.from = new;
203 	dst_hold(new);
204 }
205 
206 struct fib6_walker_t {
207 	struct list_head lh;
208 	struct fib6_node *root, *node;
209 	struct rt6_info *leaf;
210 	unsigned char state;
211 	unsigned char prune;
212 	unsigned int skip;
213 	unsigned int count;
214 	int (*func)(struct fib6_walker_t *);
215 	void *args;
216 };
217 
218 struct rt6_statistics {
219 	__u32		fib_nodes;
220 	__u32		fib_route_nodes;
221 	__u32		fib_rt_alloc;		/* permanent routes	*/
222 	__u32		fib_rt_entries;		/* rt entries in table	*/
223 	__u32		fib_rt_cache;		/* cache routes		*/
224 	__u32		fib_discarded_routes;
225 };
226 
227 #define RTN_TL_ROOT	0x0001
228 #define RTN_ROOT	0x0002		/* tree root node		*/
229 #define RTN_RTINFO	0x0004		/* node with valid routing info	*/
230 
231 /*
232  *	priority levels (or metrics)
233  *
234  */
235 
236 
237 struct fib6_table {
238 	struct hlist_node	tb6_hlist;
239 	u32			tb6_id;
240 	rwlock_t		tb6_lock;
241 	struct fib6_node	tb6_root;
242 	struct inet_peer_base	tb6_peers;
243 };
244 
245 #define RT6_TABLE_UNSPEC	RT_TABLE_UNSPEC
246 #define RT6_TABLE_MAIN		RT_TABLE_MAIN
247 #define RT6_TABLE_DFLT		RT6_TABLE_MAIN
248 #define RT6_TABLE_INFO		RT6_TABLE_MAIN
249 #define RT6_TABLE_PREFIX	RT6_TABLE_MAIN
250 
251 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
252 #define FIB6_TABLE_MIN		1
253 #define FIB6_TABLE_MAX		RT_TABLE_MAX
254 #define RT6_TABLE_LOCAL		RT_TABLE_LOCAL
255 #else
256 #define FIB6_TABLE_MIN		RT_TABLE_MAIN
257 #define FIB6_TABLE_MAX		FIB6_TABLE_MIN
258 #define RT6_TABLE_LOCAL		RT6_TABLE_MAIN
259 #endif
260 
261 typedef struct rt6_info *(*pol_lookup_t)(struct net *,
262 					 struct fib6_table *,
263 					 struct flowi6 *, int);
264 
265 /*
266  *	exported functions
267  */
268 
269 extern struct fib6_table        *fib6_get_table(struct net *net, u32 id);
270 extern struct fib6_table        *fib6_new_table(struct net *net, u32 id);
271 extern struct dst_entry         *fib6_rule_lookup(struct net *net,
272 						  struct flowi6 *fl6, int flags,
273 						  pol_lookup_t lookup);
274 
275 extern struct fib6_node		*fib6_lookup(struct fib6_node *root,
276 					     const struct in6_addr *daddr,
277 					     const struct in6_addr *saddr);
278 
279 struct fib6_node		*fib6_locate(struct fib6_node *root,
280 					     const struct in6_addr *daddr, int dst_len,
281 					     const struct in6_addr *saddr, int src_len);
282 
283 extern void			fib6_clean_all_ro(struct net *net,
284 					       int (*func)(struct rt6_info *, void *arg),
285 					       int prune, void *arg);
286 
287 extern void			fib6_clean_all(struct net *net,
288 					       int (*func)(struct rt6_info *, void *arg),
289 					       int prune, void *arg);
290 
291 extern int			fib6_add(struct fib6_node *root,
292 					 struct rt6_info *rt,
293 					 struct nl_info *info);
294 
295 extern int			fib6_del(struct rt6_info *rt,
296 					 struct nl_info *info);
297 
298 extern void			inet6_rt_notify(int event, struct rt6_info *rt,
299 						struct nl_info *info);
300 
301 extern void			fib6_run_gc(unsigned long expires,
302 					    struct net *net);
303 
304 extern void			fib6_gc_cleanup(void);
305 
306 extern int			fib6_init(void);
307 
308 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
309 extern int			fib6_rules_init(void);
310 extern void			fib6_rules_cleanup(void);
311 #else
312 static inline int               fib6_rules_init(void)
313 {
314 	return 0;
315 }
316 static inline void              fib6_rules_cleanup(void)
317 {
318 	return ;
319 }
320 #endif
321 #endif
322