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#include <linux/indirect_call_wrapper.h>
14
15struct fib_kuid_range {
16	kuid_t start;
17	kuid_t end;
18};
19
20struct fib_rule {
21	struct list_head	list;
22	int			iifindex;
23	int			oifindex;
24	u32			mark;
25	u32			mark_mask;
26	u32			flags;
27	u32			table;
28	u8			action;
29	u8			l3mdev;
30	u8                      proto;
31	u8			ip_proto;
32	u32			target;
33	__be64			tun_id;
34	struct fib_rule __rcu	*ctarget;
35	struct net		*fr_net;
36
37	refcount_t		refcnt;
38	u32			pref;
39	int			suppress_ifgroup;
40	int			suppress_prefixlen;
41	char			iifname[IFNAMSIZ];
42	char			oifname[IFNAMSIZ];
43	struct fib_kuid_range	uid_range;
44	struct fib_rule_port_range	sport_range;
45	struct fib_rule_port_range	dport_range;
46	struct rcu_head		rcu;
47};
48
49struct fib_lookup_arg {
50	void			*lookup_ptr;
51	const void		*lookup_data;
52	void			*result;
53	struct fib_rule		*rule;
54	u32			table;
55	int			flags;
56#define FIB_LOOKUP_NOREF		1
57#define FIB_LOOKUP_IGNORE_LINKSTATE	2
58};
59
60struct fib_rules_ops {
61	int			family;
62	struct list_head	list;
63	int			rule_size;
64	int			addr_size;
65	int			unresolved_rules;
66	int			nr_goto_rules;
67	unsigned int		fib_rules_seq;
68
69	int			(*action)(struct fib_rule *,
70					  struct flowi *, int,
71					  struct fib_lookup_arg *);
72	bool			(*suppress)(struct fib_rule *, int,
73					    struct fib_lookup_arg *);
74	int			(*match)(struct fib_rule *,
75					 struct flowi *, int);
76	int			(*configure)(struct fib_rule *,
77					     struct sk_buff *,
78					     struct fib_rule_hdr *,
79					     struct nlattr **,
80					     struct netlink_ext_ack *);
81	int			(*delete)(struct fib_rule *);
82	int			(*compare)(struct fib_rule *,
83					   struct fib_rule_hdr *,
84					   struct nlattr **);
85	int			(*fill)(struct fib_rule *, struct sk_buff *,
86					struct fib_rule_hdr *);
87	size_t			(*nlmsg_payload)(struct fib_rule *);
88
89	/* Called after modifications to the rules set, must flush
90	 * the route cache if one exists. */
91	void			(*flush_cache)(struct fib_rules_ops *ops);
92
93	int			nlgroup;
94	struct list_head	rules_list;
95	struct module		*owner;
96	struct net		*fro_net;
97	struct rcu_head		rcu;
98};
99
100struct fib_rule_notifier_info {
101	struct fib_notifier_info info; /* must be first */
102	struct fib_rule *rule;
103};
104
105static inline void fib_rule_get(struct fib_rule *rule)
106{
107	refcount_inc(&rule->refcnt);
108}
109
110static 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
117static 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
123static 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
130static 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
137static inline bool fib_rule_port_range_set(const struct fib_rule_port_range *range)
138{
139	return range->start != 0 && range->end != 0;
140}
141
142static inline bool fib_rule_port_inrange(const struct fib_rule_port_range *a,
143					 __be16 port)
144{
145	return ntohs(port) >= a->start &&
146		ntohs(port) <= a->end;
147}
148
149static inline bool fib_rule_port_range_valid(const struct fib_rule_port_range *a)
150{
151	return a->start != 0 && a->end != 0 && a->end < 0xffff &&
152		a->start <= a->end;
153}
154
155static inline bool fib_rule_port_range_compare(struct fib_rule_port_range *a,
156					       struct fib_rule_port_range *b)
157{
158	return a->start == b->start &&
159		a->end == b->end;
160}
161
162static inline bool fib_rule_requires_fldissect(struct fib_rule *rule)
163{
164	return rule->iifindex != LOOPBACK_IFINDEX && (rule->ip_proto ||
165		fib_rule_port_range_set(&rule->sport_range) ||
166		fib_rule_port_range_set(&rule->dport_range));
167}
168
169struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
170					 struct net *);
171void fib_rules_unregister(struct fib_rules_ops *);
172
173int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
174		     struct fib_lookup_arg *);
175int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table);
176bool fib_rule_matchall(const struct fib_rule *rule);
177int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
178		   struct netlink_ext_ack *extack);
179unsigned int fib_rules_seq_read(struct net *net, int family);
180
181int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
182		   struct netlink_ext_ack *extack);
183int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
184		   struct netlink_ext_ack *extack);
185
186INDIRECT_CALLABLE_DECLARE(int fib6_rule_match(struct fib_rule *rule,
187					    struct flowi *fl, int flags));
188INDIRECT_CALLABLE_DECLARE(int fib4_rule_match(struct fib_rule *rule,
189					    struct flowi *fl, int flags));
190
191INDIRECT_CALLABLE_DECLARE(int fib6_rule_action(struct fib_rule *rule,
192			    struct flowi *flp, int flags,
193			    struct fib_lookup_arg *arg));
194INDIRECT_CALLABLE_DECLARE(int fib4_rule_action(struct fib_rule *rule,
195			    struct flowi *flp, int flags,
196			    struct fib_lookup_arg *arg));
197
198INDIRECT_CALLABLE_DECLARE(bool fib6_rule_suppress(struct fib_rule *rule,
199						int flags,
200						struct fib_lookup_arg *arg));
201INDIRECT_CALLABLE_DECLARE(bool fib4_rule_suppress(struct fib_rule *rule,
202						int flags,
203						struct fib_lookup_arg *arg));
204#endif
205