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  	struct rcu_head		rcu;
47  };
48  
49  struct 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  
60  struct 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  
100  struct fib_rule_notifier_info {
101  	struct fib_notifier_info info; /* must be first */
102  	struct fib_rule *rule;
103  };
104  
fib_rule_get(struct fib_rule * rule)105  static inline void fib_rule_get(struct fib_rule *rule)
106  {
107  	refcount_inc(&rule->refcnt);
108  }
109  
fib_rule_put(struct fib_rule * rule)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
fib_rule_get_table(struct fib_rule * rule,struct fib_lookup_arg * arg)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
fib_rule_get_table(struct fib_rule * rule,struct fib_lookup_arg * arg)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  
frh_get_table(struct fib_rule_hdr * frh,struct nlattr ** nla)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  
fib_rule_port_range_set(const struct fib_rule_port_range * range)137  static 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  
fib_rule_port_inrange(const struct fib_rule_port_range * a,__be16 port)142  static 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  
fib_rule_port_range_valid(const struct fib_rule_port_range * a)149  static 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  
fib_rule_port_range_compare(struct fib_rule_port_range * a,struct fib_rule_port_range * b)155  static 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  
fib_rule_requires_fldissect(struct fib_rule * rule)162  static 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  
169  struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
170  					 struct net *);
171  void fib_rules_unregister(struct fib_rules_ops *);
172  
173  int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
174  		     struct fib_lookup_arg *);
175  int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table);
176  bool fib_rule_matchall(const struct fib_rule *rule);
177  int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
178  		   struct netlink_ext_ack *extack);
179  unsigned int fib_rules_seq_read(struct net *net, int family);
180  
181  int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
182  		   struct netlink_ext_ack *extack);
183  int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
184  		   struct netlink_ext_ack *extack);
185  
186  INDIRECT_CALLABLE_DECLARE(int fib6_rule_match(struct fib_rule *rule,
187  					    struct flowi *fl, int flags));
188  INDIRECT_CALLABLE_DECLARE(int fib4_rule_match(struct fib_rule *rule,
189  					    struct flowi *fl, int flags));
190  
191  INDIRECT_CALLABLE_DECLARE(int fib6_rule_action(struct fib_rule *rule,
192  			    struct flowi *flp, int flags,
193  			    struct fib_lookup_arg *arg));
194  INDIRECT_CALLABLE_DECLARE(int fib4_rule_action(struct fib_rule *rule,
195  			    struct flowi *flp, int flags,
196  			    struct fib_lookup_arg *arg));
197  
198  INDIRECT_CALLABLE_DECLARE(bool fib6_rule_suppress(struct fib_rule *rule,
199  						int flags,
200  						struct fib_lookup_arg *arg));
201  INDIRECT_CALLABLE_DECLARE(bool fib4_rule_suppress(struct fib_rule *rule,
202  						int flags,
203  						struct fib_lookup_arg *arg));
204  #endif
205