xref: /linux/include/net/fib_rules.h (revision d257f9bf06129613de539ea71ecea60848b662cd)
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 <linux/refcount.h>
9 #include <net/flow.h>
10 #include <net/rtnetlink.h>
11 
12 struct fib_kuid_range {
13 	kuid_t start;
14 	kuid_t end;
15 };
16 
17 struct fib_rule {
18 	struct list_head	list;
19 	int			iifindex;
20 	int			oifindex;
21 	u32			mark;
22 	u32			mark_mask;
23 	u32			flags;
24 	u32			table;
25 	u8			action;
26 	u8			l3mdev;
27 	/* 2 bytes hole, try to use */
28 	u32			target;
29 	__be64			tun_id;
30 	struct fib_rule __rcu	*ctarget;
31 	struct net		*fr_net;
32 
33 	refcount_t		refcnt;
34 	u32			pref;
35 	int			suppress_ifgroup;
36 	int			suppress_prefixlen;
37 	char			iifname[IFNAMSIZ];
38 	char			oifname[IFNAMSIZ];
39 	struct fib_kuid_range	uid_range;
40 	struct rcu_head		rcu;
41 };
42 
43 struct fib_lookup_arg {
44 	void			*lookup_ptr;
45 	void			*result;
46 	struct fib_rule		*rule;
47 	u32			table;
48 	int			flags;
49 #define FIB_LOOKUP_NOREF		1
50 #define FIB_LOOKUP_IGNORE_LINKSTATE	2
51 };
52 
53 struct fib_rules_ops {
54 	int			family;
55 	struct list_head	list;
56 	int			rule_size;
57 	int			addr_size;
58 	int			unresolved_rules;
59 	int			nr_goto_rules;
60 
61 	int			(*action)(struct fib_rule *,
62 					  struct flowi *, int,
63 					  struct fib_lookup_arg *);
64 	bool			(*suppress)(struct fib_rule *,
65 					    struct fib_lookup_arg *);
66 	int			(*match)(struct fib_rule *,
67 					 struct flowi *, int);
68 	int			(*configure)(struct fib_rule *,
69 					     struct sk_buff *,
70 					     struct fib_rule_hdr *,
71 					     struct nlattr **);
72 	int			(*delete)(struct fib_rule *);
73 	int			(*compare)(struct fib_rule *,
74 					   struct fib_rule_hdr *,
75 					   struct nlattr **);
76 	int			(*fill)(struct fib_rule *, struct sk_buff *,
77 					struct fib_rule_hdr *);
78 	size_t			(*nlmsg_payload)(struct fib_rule *);
79 
80 	/* Called after modifications to the rules set, must flush
81 	 * the route cache if one exists. */
82 	void			(*flush_cache)(struct fib_rules_ops *ops);
83 
84 	int			nlgroup;
85 	const struct nla_policy	*policy;
86 	struct list_head	rules_list;
87 	struct module		*owner;
88 	struct net		*fro_net;
89 	struct rcu_head		rcu;
90 };
91 
92 #define FRA_GENERIC_POLICY \
93 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
94 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
95 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
96 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
97 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
98 	[FRA_TABLE]     = { .type = NLA_U32 }, \
99 	[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
100 	[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
101 	[FRA_GOTO]	= { .type = NLA_U32 }, \
102 	[FRA_L3MDEV]	= { .type = NLA_U8 }, \
103 	[FRA_UID_RANGE]	= { .len = sizeof(struct fib_rule_uid_range) }
104 
105 static inline void fib_rule_get(struct fib_rule *rule)
106 {
107 	refcount_inc(&rule->refcnt);
108 }
109 
110 static inline void fib_rule_put(struct fib_rule *rule)
111 {
112 	if (refcount_dec_and_test(&rule->refcnt))
113 		kfree_rcu(rule, rcu);
114 }
115 
116 #ifdef CONFIG_NET_L3_MASTER_DEV
117 static inline u32 fib_rule_get_table(struct fib_rule *rule,
118 				     struct fib_lookup_arg *arg)
119 {
120 	return rule->l3mdev ? arg->table : rule->table;
121 }
122 #else
123 static inline u32 fib_rule_get_table(struct fib_rule *rule,
124 				     struct fib_lookup_arg *arg)
125 {
126 	return rule->table;
127 }
128 #endif
129 
130 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
131 {
132 	if (nla[FRA_TABLE])
133 		return nla_get_u32(nla[FRA_TABLE]);
134 	return frh->table;
135 }
136 
137 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
138 					 struct net *);
139 void fib_rules_unregister(struct fib_rules_ops *);
140 
141 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
142 		     struct fib_lookup_arg *);
143 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
144 			 u32 flags);
145 bool fib_rule_matchall(const struct fib_rule *rule);
146 
147 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
148 		   struct netlink_ext_ack *extack);
149 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
150 		   struct netlink_ext_ack *extack);
151 #endif
152