1 /*
2  *	Linux INET6 implementation
3  *
4  *	Authors:
5  *	Pedro Roque		<pedro_m@yahoo.com>
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 #ifdef __KERNEL__
17 
18 #include <linux/ipv6_route.h>
19 
20 #include <net/dst.h>
21 #include <net/flow.h>
22 #include <linux/rtnetlink.h>
23 
24 struct rt6_info;
25 
26 struct fib6_node
27 {
28 	struct fib6_node	*parent;
29 	struct fib6_node	*left;
30 	struct fib6_node	*right;
31 
32 	struct fib6_node	*subtree;
33 
34 	struct rt6_info		*leaf;
35 
36 	__u16			fn_bit;		/* bit key */
37 	__u16			fn_flags;
38 	__u32			fn_sernum;
39 };
40 
41 
42 /*
43  *	routing information
44  *
45  */
46 
47 struct rt6key
48 {
49 	struct in6_addr	addr;
50 	int		plen;
51 };
52 
53 struct rt6_info
54 {
55 	union {
56 		struct dst_entry	dst;
57 		struct rt6_info		*next;
58 	} u;
59 
60 #define rt6i_dev			u.dst.dev
61 #define rt6i_nexthop			u.dst.neighbour
62 #define rt6i_expires			u.dst.expires
63 
64 	struct fib6_node		*rt6i_node;
65 
66 	struct in6_addr			rt6i_gateway;
67 
68 	u32				rt6i_flags;
69 	u32				rt6i_metric;
70 	u8				rt6i_hoplimit;
71 	atomic_t			rt6i_ref;
72 
73 	union {
74 		struct flow_rule	*rt6iu_flowr;
75 		struct flow_filter	*rt6iu_filter;
76 	} flow_u;
77 
78 #define rt6i_flowr			flow_u.rt6iu_flowr
79 #define rt6i_filter			flow_u.rt6iu_filter
80 
81 	struct rt6key			rt6i_dst;
82 	struct rt6key			rt6i_src;
83 
84 	u8				rt6i_protocol;
85 };
86 
87 struct fib6_walker_t
88 {
89 	struct fib6_walker_t *prev, *next;
90 	struct fib6_node *root, *node;
91 	struct rt6_info *leaf;
92 	unsigned char state;
93 	unsigned char prune;
94 	int (*func)(struct fib6_walker_t *);
95 	void *args;
96 };
97 
98 extern struct fib6_walker_t fib6_walker_list;
99 extern rwlock_t fib6_walker_lock;
100 
fib6_walker_link(struct fib6_walker_t * w)101 static inline void fib6_walker_link(struct fib6_walker_t *w)
102 {
103 	write_lock_bh(&fib6_walker_lock);
104 	w->next = fib6_walker_list.next;
105 	w->prev = &fib6_walker_list;
106 	w->next->prev = w;
107 	w->prev->next = w;
108 	write_unlock_bh(&fib6_walker_lock);
109 }
110 
fib6_walker_unlink(struct fib6_walker_t * w)111 static inline void fib6_walker_unlink(struct fib6_walker_t *w)
112 {
113 	write_lock_bh(&fib6_walker_lock);
114 	w->next->prev = w->prev;
115 	w->prev->next = w->next;
116 	w->prev = w->next = w;
117 	write_unlock_bh(&fib6_walker_lock);
118 }
119 
120 struct rt6_statistics {
121 	__u32		fib_nodes;
122 	__u32		fib_route_nodes;
123 	__u32		fib_rt_alloc;		/* permanent routes	*/
124 	__u32		fib_rt_entries;		/* rt entries in table	*/
125 	__u32		fib_rt_cache;		/* cache routes		*/
126 };
127 
128 #define RTN_TL_ROOT	0x0001
129 #define RTN_ROOT	0x0002		/* tree root node		*/
130 #define RTN_RTINFO	0x0004		/* node with valid routing info	*/
131 
132 /*
133  *	priority levels (or metrics)
134  *
135  */
136 
137 #define RTPRI_FIREWALL	8		/* Firewall control information	*/
138 #define RTPRI_FLOW	16		/* Flow based forwarding rules	*/
139 #define RTPRI_KERN_CTL	32		/* Kernel control routes	*/
140 
141 #define RTPRI_USER_MIN	256		/* Mimimum user priority	*/
142 #define RTPRI_USER_MAX	1024		/* Maximum user priority	*/
143 
144 #define RTPRI_KERN_DFLT	4096		/* Kernel default routes	*/
145 
146 #define	MAX_FLOW_BACKTRACE	32
147 
148 
149 typedef void			(*f_pnode)(struct fib6_node *fn, void *);
150 
151 extern struct fib6_node		ip6_routing_table;
152 
153 /*
154  *	exported functions
155  */
156 
157 extern struct fib6_node		*fib6_lookup(struct fib6_node *root,
158 					     struct in6_addr *daddr,
159 					     struct in6_addr *saddr);
160 
161 struct fib6_node		*fib6_locate(struct fib6_node *root,
162 					     struct in6_addr *daddr, int dst_len,
163 					     struct in6_addr *saddr, int src_len);
164 
165 extern void			fib6_clean_tree(struct fib6_node *root,
166 						int (*func)(struct rt6_info *, void *arg),
167 						int prune, void *arg);
168 
169 extern int			fib6_walk(struct fib6_walker_t *w);
170 extern int			fib6_walk_continue(struct fib6_walker_t *w);
171 
172 extern int			fib6_add(struct fib6_node *root,
173 					 struct rt6_info *rt,
174 					 struct nlmsghdr *nlh,
175 					 struct netlink_skb_parms *req);
176 
177 extern int			fib6_del(struct rt6_info *rt,
178 					 struct nlmsghdr *nlh,
179 					 struct netlink_skb_parms *req);
180 
181 extern void			inet6_rt_notify(int event, struct rt6_info *rt,
182 						struct nlmsghdr *nlh,
183 						struct netlink_skb_parms *req);
184 
185 extern void			fib6_run_gc(unsigned long dummy);
186 
187 extern void			fib6_gc_cleanup(void);
188 
189 extern void			fib6_init(void);
190 #endif
191 #endif
192