xref: /linux/include/net/fib_rules.h (revision d96fc832bcb6269d96e33d506f33033d7ed08598)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_FIB_RULES_H
3 #define __NET_FIB_RULES_H
4 
5 #include <linux/types.h>
6 #include <linux/slab.h>
7 #include <linux/netdevice.h>
8 #include <linux/fib_rules.h>
9 #include <linux/refcount.h>
10 #include <net/flow.h>
11 #include <net/rtnetlink.h>
12 #include <net/fib_notifier.h>
13 
14 struct fib_kuid_range {
15 	kuid_t start;
16 	kuid_t end;
17 };
18 
19 struct fib_rule {
20 	struct list_head	list;
21 	int			iifindex;
22 	int			oifindex;
23 	u32			mark;
24 	u32			mark_mask;
25 	u32			flags;
26 	u32			table;
27 	u8			action;
28 	u8			l3mdev;
29 	u8                      proto;
30 	/* 1 byte hole, try to use */
31 	u32			target;
32 	__be64			tun_id;
33 	struct fib_rule __rcu	*ctarget;
34 	struct net		*fr_net;
35 
36 	refcount_t		refcnt;
37 	u32			pref;
38 	int			suppress_ifgroup;
39 	int			suppress_prefixlen;
40 	char			iifname[IFNAMSIZ];
41 	char			oifname[IFNAMSIZ];
42 	struct fib_kuid_range	uid_range;
43 	struct rcu_head		rcu;
44 };
45 
46 struct fib_lookup_arg {
47 	void			*lookup_ptr;
48 	void			*result;
49 	struct fib_rule		*rule;
50 	u32			table;
51 	int			flags;
52 #define FIB_LOOKUP_NOREF		1
53 #define FIB_LOOKUP_IGNORE_LINKSTATE	2
54 };
55 
56 struct fib_rules_ops {
57 	int			family;
58 	struct list_head	list;
59 	int			rule_size;
60 	int			addr_size;
61 	int			unresolved_rules;
62 	int			nr_goto_rules;
63 	unsigned int		fib_rules_seq;
64 
65 	int			(*action)(struct fib_rule *,
66 					  struct flowi *, int,
67 					  struct fib_lookup_arg *);
68 	bool			(*suppress)(struct fib_rule *,
69 					    struct fib_lookup_arg *);
70 	int			(*match)(struct fib_rule *,
71 					 struct flowi *, int);
72 	int			(*configure)(struct fib_rule *,
73 					     struct sk_buff *,
74 					     struct fib_rule_hdr *,
75 					     struct nlattr **);
76 	int			(*delete)(struct fib_rule *);
77 	int			(*compare)(struct fib_rule *,
78 					   struct fib_rule_hdr *,
79 					   struct nlattr **);
80 	int			(*fill)(struct fib_rule *, struct sk_buff *,
81 					struct fib_rule_hdr *);
82 	size_t			(*nlmsg_payload)(struct fib_rule *);
83 
84 	/* Called after modifications to the rules set, must flush
85 	 * the route cache if one exists. */
86 	void			(*flush_cache)(struct fib_rules_ops *ops);
87 
88 	int			nlgroup;
89 	const struct nla_policy	*policy;
90 	struct list_head	rules_list;
91 	struct module		*owner;
92 	struct net		*fro_net;
93 	struct rcu_head		rcu;
94 };
95 
96 struct fib_rule_notifier_info {
97 	struct fib_notifier_info info; /* must be first */
98 	struct fib_rule *rule;
99 };
100 
101 #define FRA_GENERIC_POLICY \
102 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
103 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
104 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
105 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
106 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
107 	[FRA_TABLE]     = { .type = NLA_U32 }, \
108 	[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
109 	[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
110 	[FRA_GOTO]	= { .type = NLA_U32 }, \
111 	[FRA_L3MDEV]	= { .type = NLA_U8 }, \
112 	[FRA_UID_RANGE]	= { .len = sizeof(struct fib_rule_uid_range) }, \
113 	[FRA_PROTOCOL]  = { .type = NLA_U8 }
114 
115 static inline void fib_rule_get(struct fib_rule *rule)
116 {
117 	refcount_inc(&rule->refcnt);
118 }
119 
120 static inline void fib_rule_put(struct fib_rule *rule)
121 {
122 	if (refcount_dec_and_test(&rule->refcnt))
123 		kfree_rcu(rule, rcu);
124 }
125 
126 #ifdef CONFIG_NET_L3_MASTER_DEV
127 static inline u32 fib_rule_get_table(struct fib_rule *rule,
128 				     struct fib_lookup_arg *arg)
129 {
130 	return rule->l3mdev ? arg->table : rule->table;
131 }
132 #else
133 static inline u32 fib_rule_get_table(struct fib_rule *rule,
134 				     struct fib_lookup_arg *arg)
135 {
136 	return rule->table;
137 }
138 #endif
139 
140 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
141 {
142 	if (nla[FRA_TABLE])
143 		return nla_get_u32(nla[FRA_TABLE]);
144 	return frh->table;
145 }
146 
147 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
148 					 struct net *);
149 void fib_rules_unregister(struct fib_rules_ops *);
150 
151 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
152 		     struct fib_lookup_arg *);
153 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
154 			 u32 flags);
155 bool fib_rule_matchall(const struct fib_rule *rule);
156 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family);
157 unsigned int fib_rules_seq_read(struct net *net, int family);
158 
159 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
160 		   struct netlink_ext_ack *extack);
161 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
162 		   struct netlink_ext_ack *extack);
163 #endif
164