xref: /openbmc/linux/include/net/fib_rules.h (revision 82e6fdd6)
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 	/* 2 bytes hole, try to use */
30 	u32			target;
31 	__be64			tun_id;
32 	struct fib_rule __rcu	*ctarget;
33 	struct net		*fr_net;
34 
35 	refcount_t		refcnt;
36 	u32			pref;
37 	int			suppress_ifgroup;
38 	int			suppress_prefixlen;
39 	char			iifname[IFNAMSIZ];
40 	char			oifname[IFNAMSIZ];
41 	struct fib_kuid_range	uid_range;
42 	struct rcu_head		rcu;
43 };
44 
45 struct fib_lookup_arg {
46 	void			*lookup_ptr;
47 	void			*result;
48 	struct fib_rule		*rule;
49 	u32			table;
50 	int			flags;
51 #define FIB_LOOKUP_NOREF		1
52 #define FIB_LOOKUP_IGNORE_LINKSTATE	2
53 };
54 
55 struct fib_rules_ops {
56 	int			family;
57 	struct list_head	list;
58 	int			rule_size;
59 	int			addr_size;
60 	int			unresolved_rules;
61 	int			nr_goto_rules;
62 	unsigned int		fib_rules_seq;
63 
64 	int			(*action)(struct fib_rule *,
65 					  struct flowi *, int,
66 					  struct fib_lookup_arg *);
67 	bool			(*suppress)(struct fib_rule *,
68 					    struct fib_lookup_arg *);
69 	int			(*match)(struct fib_rule *,
70 					 struct flowi *, int);
71 	int			(*configure)(struct fib_rule *,
72 					     struct sk_buff *,
73 					     struct fib_rule_hdr *,
74 					     struct nlattr **);
75 	int			(*delete)(struct fib_rule *);
76 	int			(*compare)(struct fib_rule *,
77 					   struct fib_rule_hdr *,
78 					   struct nlattr **);
79 	int			(*fill)(struct fib_rule *, struct sk_buff *,
80 					struct fib_rule_hdr *);
81 	size_t			(*nlmsg_payload)(struct fib_rule *);
82 
83 	/* Called after modifications to the rules set, must flush
84 	 * the route cache if one exists. */
85 	void			(*flush_cache)(struct fib_rules_ops *ops);
86 
87 	int			nlgroup;
88 	const struct nla_policy	*policy;
89 	struct list_head	rules_list;
90 	struct module		*owner;
91 	struct net		*fro_net;
92 	struct rcu_head		rcu;
93 };
94 
95 struct fib_rule_notifier_info {
96 	struct fib_notifier_info info; /* must be first */
97 	struct fib_rule *rule;
98 };
99 
100 #define FRA_GENERIC_POLICY \
101 	[FRA_IIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
102 	[FRA_OIFNAME]	= { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
103 	[FRA_PRIORITY]	= { .type = NLA_U32 }, \
104 	[FRA_FWMARK]	= { .type = NLA_U32 }, \
105 	[FRA_FWMASK]	= { .type = NLA_U32 }, \
106 	[FRA_TABLE]     = { .type = NLA_U32 }, \
107 	[FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
108 	[FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
109 	[FRA_GOTO]	= { .type = NLA_U32 }, \
110 	[FRA_L3MDEV]	= { .type = NLA_U8 }, \
111 	[FRA_UID_RANGE]	= { .len = sizeof(struct fib_rule_uid_range) }
112 
113 static inline void fib_rule_get(struct fib_rule *rule)
114 {
115 	refcount_inc(&rule->refcnt);
116 }
117 
118 static inline void fib_rule_put(struct fib_rule *rule)
119 {
120 	if (refcount_dec_and_test(&rule->refcnt))
121 		kfree_rcu(rule, rcu);
122 }
123 
124 #ifdef CONFIG_NET_L3_MASTER_DEV
125 static inline u32 fib_rule_get_table(struct fib_rule *rule,
126 				     struct fib_lookup_arg *arg)
127 {
128 	return rule->l3mdev ? arg->table : rule->table;
129 }
130 #else
131 static inline u32 fib_rule_get_table(struct fib_rule *rule,
132 				     struct fib_lookup_arg *arg)
133 {
134 	return rule->table;
135 }
136 #endif
137 
138 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
139 {
140 	if (nla[FRA_TABLE])
141 		return nla_get_u32(nla[FRA_TABLE]);
142 	return frh->table;
143 }
144 
145 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
146 					 struct net *);
147 void fib_rules_unregister(struct fib_rules_ops *);
148 
149 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
150 		     struct fib_lookup_arg *);
151 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
152 			 u32 flags);
153 bool fib_rule_matchall(const struct fib_rule *rule);
154 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family);
155 unsigned int fib_rules_seq_read(struct net *net, int family);
156 
157 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
158 		   struct netlink_ext_ack *extack);
159 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
160 		   struct netlink_ext_ack *extack);
161 #endif
162