xref: /linux/include/net/fib_rules.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 	int			iifindex;
14 	int			oifindex;
15 	u32			mark;
16 	u32			mark_mask;
17 	u32			flags;
18 	u32			table;
19 	u8			action;
20 	/* 3 bytes hole, try to use */
21 	u32			target;
22 	struct fib_rule __rcu	*ctarget;
23 	struct net		*fr_net;
24 
25 	atomic_t		refcnt;
26 	u32			pref;
27 	int			suppress_ifgroup;
28 	int			suppress_prefixlen;
29 	char			iifname[IFNAMSIZ];
30 	char			oifname[IFNAMSIZ];
31 	struct rcu_head		rcu;
32 };
33 
34 struct fib_lookup_arg {
35 	void			*lookup_ptr;
36 	void			*result;
37 	struct fib_rule		*rule;
38 	int			flags;
39 #define FIB_LOOKUP_NOREF	1
40 };
41 
42 struct fib_rules_ops {
43 	int			family;
44 	struct list_head	list;
45 	int			rule_size;
46 	int			addr_size;
47 	int			unresolved_rules;
48 	int			nr_goto_rules;
49 
50 	int			(*action)(struct fib_rule *,
51 					  struct flowi *, int,
52 					  struct fib_lookup_arg *);
53 	bool			(*suppress)(struct fib_rule *,
54 					    struct fib_lookup_arg *);
55 	int			(*match)(struct fib_rule *,
56 					 struct flowi *, int);
57 	int			(*configure)(struct fib_rule *,
58 					     struct sk_buff *,
59 					     struct fib_rule_hdr *,
60 					     struct nlattr **);
61 	void			(*delete)(struct fib_rule *);
62 	int			(*compare)(struct fib_rule *,
63 					   struct fib_rule_hdr *,
64 					   struct nlattr **);
65 	int			(*fill)(struct fib_rule *, struct sk_buff *,
66 					struct fib_rule_hdr *);
67 	u32			(*default_pref)(struct fib_rules_ops *ops);
68 	size_t			(*nlmsg_payload)(struct fib_rule *);
69 
70 	/* Called after modifications to the rules set, must flush
71 	 * the route cache if one exists. */
72 	void			(*flush_cache)(struct fib_rules_ops *ops);
73 
74 	int			nlgroup;
75 	const struct nla_policy	*policy;
76 	struct list_head	rules_list;
77 	struct module		*owner;
78 	struct net		*fro_net;
79 	struct rcu_head		rcu;
80 };
81 
82 #define FRA_GENERIC_POLICY \
83 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
84 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
85 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
86 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
87 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
88 	[FRA_TABLE]     = { .type = NLA_U32 }, \
89 	[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
90 	[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
91 	[FRA_GOTO]	= { .type = NLA_U32 }
92 
93 static inline void fib_rule_get(struct fib_rule *rule)
94 {
95 	atomic_inc(&rule->refcnt);
96 }
97 
98 static inline void fib_rule_put_rcu(struct rcu_head *head)
99 {
100 	struct fib_rule *rule = container_of(head, struct fib_rule, rcu);
101 	release_net(rule->fr_net);
102 	kfree(rule);
103 }
104 
105 static inline void fib_rule_put(struct fib_rule *rule)
106 {
107 	if (atomic_dec_and_test(&rule->refcnt))
108 		call_rcu(&rule->rcu, fib_rule_put_rcu);
109 }
110 
111 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
112 {
113 	if (nla[FRA_TABLE])
114 		return nla_get_u32(nla[FRA_TABLE]);
115 	return frh->table;
116 }
117 
118 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
119 					 struct net *);
120 void fib_rules_unregister(struct fib_rules_ops *);
121 
122 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
123 		     struct fib_lookup_arg *);
124 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
125 			 u32 flags);
126 u32 fib_default_rule_pref(struct fib_rules_ops *ops);
127 #endif
128