xref: /openbmc/linux/include/net/ip6_fib.h (revision 8684014d)
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
323