xref: /linux/include/net/fib_rules.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 #ifndef __NET_FIB_RULES_H
2 #define __NET_FIB_RULES_H
3 
4 #include <linux/types.h>
5 #include <linux/slab.h>
6 #include <linux/netdevice.h>
7 #include <linux/fib_rules.h>
8 #include <net/flow.h>
9 #include <net/rtnetlink.h>
10 
11 struct fib_rule {
12 	struct list_head	list;
13 	atomic_t		refcnt;
14 	int			iifindex;
15 	int			oifindex;
16 	u32			mark;
17 	u32			mark_mask;
18 	u32			pref;
19 	u32			flags;
20 	u32			table;
21 	u8			action;
22 	u32			target;
23 	struct fib_rule __rcu	*ctarget;
24 	char			iifname[IFNAMSIZ];
25 	char			oifname[IFNAMSIZ];
26 	struct rcu_head		rcu;
27 	struct net *		fr_net;
28 };
29 
30 struct fib_lookup_arg {
31 	void			*lookup_ptr;
32 	void			*result;
33 	struct fib_rule		*rule;
34 	int			flags;
35 #define FIB_LOOKUP_NOREF	1
36 };
37 
38 struct fib_rules_ops {
39 	int			family;
40 	struct list_head	list;
41 	int			rule_size;
42 	int			addr_size;
43 	int			unresolved_rules;
44 	int			nr_goto_rules;
45 
46 	int			(*action)(struct fib_rule *,
47 					  struct flowi *, int,
48 					  struct fib_lookup_arg *);
49 	int			(*match)(struct fib_rule *,
50 					 struct flowi *, int);
51 	int			(*configure)(struct fib_rule *,
52 					     struct sk_buff *,
53 					     struct fib_rule_hdr *,
54 					     struct nlattr **);
55 	void			(*delete)(struct fib_rule *);
56 	int			(*compare)(struct fib_rule *,
57 					   struct fib_rule_hdr *,
58 					   struct nlattr **);
59 	int			(*fill)(struct fib_rule *, struct sk_buff *,
60 					struct fib_rule_hdr *);
61 	u32			(*default_pref)(struct fib_rules_ops *ops);
62 	size_t			(*nlmsg_payload)(struct fib_rule *);
63 
64 	/* Called after modifications to the rules set, must flush
65 	 * the route cache if one exists. */
66 	void			(*flush_cache)(struct fib_rules_ops *ops);
67 
68 	int			nlgroup;
69 	const struct nla_policy	*policy;
70 	struct list_head	rules_list;
71 	struct module		*owner;
72 	struct net		*fro_net;
73 	struct rcu_head		rcu;
74 };
75 
76 #define FRA_GENERIC_POLICY \
77 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
78 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
79 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
80 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
81 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
82 	[FRA_TABLE]     = { .type = NLA_U32 }, \
83 	[FRA_GOTO]	= { .type = NLA_U32 }
84 
85 static inline void fib_rule_get(struct fib_rule *rule)
86 {
87 	atomic_inc(&rule->refcnt);
88 }
89 
90 static inline void fib_rule_put_rcu(struct rcu_head *head)
91 {
92 	struct fib_rule *rule = container_of(head, struct fib_rule, rcu);
93 	release_net(rule->fr_net);
94 	kfree(rule);
95 }
96 
97 static inline void fib_rule_put(struct fib_rule *rule)
98 {
99 	if (atomic_dec_and_test(&rule->refcnt))
100 		call_rcu(&rule->rcu, fib_rule_put_rcu);
101 }
102 
103 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
104 {
105 	if (nla[FRA_TABLE])
106 		return nla_get_u32(nla[FRA_TABLE]);
107 	return frh->table;
108 }
109 
110 extern struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *, struct net *);
111 extern void fib_rules_unregister(struct fib_rules_ops *);
112 
113 extern int			fib_rules_lookup(struct fib_rules_ops *,
114 						 struct flowi *, int flags,
115 						 struct fib_lookup_arg *);
116 extern int			fib_default_rule_add(struct fib_rules_ops *,
117 						     u32 pref, u32 table,
118 						     u32 flags);
119 extern u32			fib_default_rule_pref(struct fib_rules_ops *ops);
120 #endif
121