xref: /linux/include/net/fib_rules.h (revision 91ec2035134982b98fab0609a9fd8480e8217dc1)
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 
15 struct fib_kuid_range {
16 	kuid_t start;
17 	kuid_t end;
18 };
19 
20 struct 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 	u16			sport_mask;
47 	u16			dport_mask;
48 	u8                      iif_is_l3_master;
49 	u8                      oif_is_l3_master;
50 	struct rcu_head		rcu;
51 };
52 
53 struct fib_lookup_arg {
54 	void			*lookup_ptr;
55 	const void		*lookup_data;
56 	void			*result;
57 	struct fib_rule		*rule;
58 	u32			table;
59 	int			flags;
60 #define FIB_LOOKUP_NOREF		1
61 #define FIB_LOOKUP_IGNORE_LINKSTATE	2
62 };
63 
64 struct fib_rules_ops {
65 	int			family;
66 	struct list_head	list;
67 	int			rule_size;
68 	int			addr_size;
69 	int			unresolved_rules;
70 	int			nr_goto_rules;
71 	unsigned int		fib_rules_seq;
72 
73 	int			(*action)(struct fib_rule *,
74 					  struct flowi *, int,
75 					  struct fib_lookup_arg *);
76 	bool			(*suppress)(struct fib_rule *, int,
77 					    struct fib_lookup_arg *);
78 	int			(*match)(struct fib_rule *,
79 					 struct flowi *, int);
80 	int			(*configure)(struct fib_rule *,
81 					     struct sk_buff *,
82 					     struct fib_rule_hdr *,
83 					     struct nlattr **,
84 					     struct netlink_ext_ack *);
85 	void			(*delete)(struct fib_rule *);
86 	int			(*compare)(struct fib_rule *,
87 					   struct fib_rule_hdr *,
88 					   struct nlattr **);
89 	int			(*fill)(struct fib_rule *, struct sk_buff *,
90 					struct fib_rule_hdr *);
91 	size_t			(*nlmsg_payload)(struct fib_rule *);
92 
93 	/* Called after modifications to the rules set, must flush
94 	 * the route cache if one exists. */
95 	void			(*flush_cache)(struct fib_rules_ops *ops);
96 	bool			(*need_rtnl)(struct net *net);
97 
98 	int			nlgroup;
99 	struct list_head	rules_list;
100 	struct module		*owner;
101 	struct net		*fro_net;
102 	struct mutex		lock;
103 	struct rcu_head		rcu;
104 };
105 
106 struct fib_rule_notifier_info {
107 	struct fib_notifier_info info; /* must be first */
108 	struct fib_rule *rule;
109 };
110 
fib_rule_get(struct fib_rule * rule)111 static inline void fib_rule_get(struct fib_rule *rule)
112 {
113 	refcount_inc(&rule->refcnt);
114 }
115 
fib_rule_get_safe(struct fib_rule * rule)116 static inline bool fib_rule_get_safe(struct fib_rule *rule)
117 {
118 	return refcount_inc_not_zero(&rule->refcnt);
119 }
120 
fib_rule_put(struct fib_rule * rule)121 static inline void fib_rule_put(struct fib_rule *rule)
122 {
123 	if (refcount_dec_and_test(&rule->refcnt))
124 		kfree_rcu(rule, rcu);
125 }
126 
127 #ifdef CONFIG_NET_L3_MASTER_DEV
fib_rule_get_table(struct fib_rule * rule,struct fib_lookup_arg * arg)128 static inline u32 fib_rule_get_table(struct fib_rule *rule,
129 				     struct fib_lookup_arg *arg)
130 {
131 	return rule->l3mdev ? arg->table : rule->table;
132 }
133 #else
fib_rule_get_table(struct fib_rule * rule,struct fib_lookup_arg * arg)134 static inline u32 fib_rule_get_table(struct fib_rule *rule,
135 				     struct fib_lookup_arg *arg)
136 {
137 	return rule->table;
138 }
139 #endif
140 
frh_get_table(struct fib_rule_hdr * frh,struct nlattr ** nla)141 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
142 {
143 	if (nla[FRA_TABLE])
144 		return nla_get_u32(nla[FRA_TABLE]);
145 	return frh->table;
146 }
147 
fib_rule_port_range_set(const struct fib_rule_port_range * range)148 static inline bool fib_rule_port_range_set(const struct fib_rule_port_range *range)
149 {
150 	return range->start != 0 && range->end != 0;
151 }
152 
fib_rule_port_inrange(const struct fib_rule_port_range * a,__be16 port)153 static inline bool fib_rule_port_inrange(const struct fib_rule_port_range *a,
154 					 __be16 port)
155 {
156 	return ntohs(port) >= a->start &&
157 		ntohs(port) <= a->end;
158 }
159 
fib_rule_port_match(const struct fib_rule_port_range * range,u16 port_mask,__be16 port)160 static inline bool fib_rule_port_match(const struct fib_rule_port_range *range,
161 				       u16 port_mask, __be16 port)
162 {
163 	if ((range->start ^ ntohs(port)) & port_mask)
164 		return false;
165 	if (!port_mask && fib_rule_port_range_set(range) &&
166 	    !fib_rule_port_inrange(range, port))
167 		return false;
168 	return true;
169 }
170 
fib_rule_port_range_valid(const struct fib_rule_port_range * a)171 static inline bool fib_rule_port_range_valid(const struct fib_rule_port_range *a)
172 {
173 	return a->start != 0 && a->end != 0 && a->end < 0xffff &&
174 		a->start <= a->end;
175 }
176 
fib_rule_port_range_compare(struct fib_rule_port_range * a,struct fib_rule_port_range * b)177 static inline bool fib_rule_port_range_compare(struct fib_rule_port_range *a,
178 					       struct fib_rule_port_range *b)
179 {
180 	return a->start == b->start &&
181 		a->end == b->end;
182 }
183 
184 static inline bool
fib_rule_port_is_range(const struct fib_rule_port_range * range)185 fib_rule_port_is_range(const struct fib_rule_port_range *range)
186 {
187 	return range->start != range->end;
188 }
189 
fib_rule_requires_fldissect(struct fib_rule * rule)190 static inline bool fib_rule_requires_fldissect(struct fib_rule *rule)
191 {
192 	return rule->iifindex != LOOPBACK_IFINDEX && (rule->ip_proto ||
193 		fib_rule_port_range_set(&rule->sport_range) ||
194 		fib_rule_port_range_set(&rule->dport_range));
195 }
196 
197 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
198 					 struct net *);
199 void fib_rules_unregister(struct fib_rules_ops *);
200 
201 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
202 		     struct fib_lookup_arg *);
203 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table);
204 bool fib_rule_matchall(const struct fib_rule *rule);
205 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
206 		   struct netlink_ext_ack *extack);
207 unsigned int fib_rules_seq_read(const struct net *net, int family);
208 
209 int fib_newrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh,
210 		struct netlink_ext_ack *extack, bool rtnl_held);
211 int fib_delrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh,
212 		struct netlink_ext_ack *extack, bool rtnl_held);
213 
214 INDIRECT_CALLABLE_DECLARE(int fib6_rule_match(struct fib_rule *rule,
215 					    struct flowi *fl, int flags));
216 INDIRECT_CALLABLE_DECLARE(int fib4_rule_match(struct fib_rule *rule,
217 					    struct flowi *fl, int flags));
218 
219 INDIRECT_CALLABLE_DECLARE(int fib6_rule_action(struct fib_rule *rule,
220 			    struct flowi *flp, int flags,
221 			    struct fib_lookup_arg *arg));
222 INDIRECT_CALLABLE_DECLARE(int fib4_rule_action(struct fib_rule *rule,
223 			    struct flowi *flp, int flags,
224 			    struct fib_lookup_arg *arg));
225 
226 INDIRECT_CALLABLE_DECLARE(bool fib6_rule_suppress(struct fib_rule *rule,
227 						int flags,
228 						struct fib_lookup_arg *arg));
229 INDIRECT_CALLABLE_DECLARE(bool fib4_rule_suppress(struct fib_rule *rule,
230 						int flags,
231 						struct fib_lookup_arg *arg));
232 #endif
233