xref: /linux/include/net/fib_rules.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 #define FIB_LOOKUP_IGNORE_LINKSTATE	2
41 };
42 
43 struct fib_rules_ops {
44 	int			family;
45 	struct list_head	list;
46 	int			rule_size;
47 	int			addr_size;
48 	int			unresolved_rules;
49 	int			nr_goto_rules;
50 
51 	int			(*action)(struct fib_rule *,
52 					  struct flowi *, int,
53 					  struct fib_lookup_arg *);
54 	bool			(*suppress)(struct fib_rule *,
55 					    struct fib_lookup_arg *);
56 	int			(*match)(struct fib_rule *,
57 					 struct flowi *, int);
58 	int			(*configure)(struct fib_rule *,
59 					     struct sk_buff *,
60 					     struct fib_rule_hdr *,
61 					     struct nlattr **);
62 	int			(*delete)(struct fib_rule *);
63 	int			(*compare)(struct fib_rule *,
64 					   struct fib_rule_hdr *,
65 					   struct nlattr **);
66 	int			(*fill)(struct fib_rule *, struct sk_buff *,
67 					struct fib_rule_hdr *);
68 	u32			(*default_pref)(struct fib_rules_ops *ops);
69 	size_t			(*nlmsg_payload)(struct fib_rule *);
70 
71 	/* Called after modifications to the rules set, must flush
72 	 * the route cache if one exists. */
73 	void			(*flush_cache)(struct fib_rules_ops *ops);
74 
75 	int			nlgroup;
76 	const struct nla_policy	*policy;
77 	struct list_head	rules_list;
78 	struct module		*owner;
79 	struct net		*fro_net;
80 	struct rcu_head		rcu;
81 };
82 
83 #define FRA_GENERIC_POLICY \
84 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
85 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
86 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
87 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
88 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
89 	[FRA_TABLE]     = { .type = NLA_U32 }, \
90 	[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
91 	[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
92 	[FRA_GOTO]	= { .type = NLA_U32 }
93 
94 static inline void fib_rule_get(struct fib_rule *rule)
95 {
96 	atomic_inc(&rule->refcnt);
97 }
98 
99 static inline void fib_rule_put(struct fib_rule *rule)
100 {
101 	if (atomic_dec_and_test(&rule->refcnt))
102 		kfree_rcu(rule, rcu);
103 }
104 
105 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
106 {
107 	if (nla[FRA_TABLE])
108 		return nla_get_u32(nla[FRA_TABLE]);
109 	return frh->table;
110 }
111 
112 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
113 					 struct net *);
114 void fib_rules_unregister(struct fib_rules_ops *);
115 
116 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
117 		     struct fib_lookup_arg *);
118 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
119 			 u32 flags);
120 u32 fib_default_rule_pref(struct fib_rules_ops *ops);
121 #endif
122