xref: /openbmc/linux/include/net/inetpeer.h (revision 8cb5d748)
1 /*
2  *		INETPEER - A storage for permanent information about peers
3  *
4  *  Authors:	Andrey V. Savochkin <saw@msu.ru>
5  */
6 
7 #ifndef _NET_INETPEER_H
8 #define _NET_INETPEER_H
9 
10 #include <linux/types.h>
11 #include <linux/init.h>
12 #include <linux/jiffies.h>
13 #include <linux/spinlock.h>
14 #include <linux/rtnetlink.h>
15 #include <net/ipv6.h>
16 #include <linux/atomic.h>
17 
18 /* IPv4 address key for cache lookups */
19 struct ipv4_addr_key {
20 	__be32	addr;
21 	int	vif;
22 };
23 
24 #define INETPEER_MAXKEYSZ   (sizeof(struct in6_addr) / sizeof(u32))
25 
26 struct inetpeer_addr {
27 	union {
28 		struct ipv4_addr_key	a4;
29 		struct in6_addr		a6;
30 		u32			key[INETPEER_MAXKEYSZ];
31 	};
32 	__u16				family;
33 };
34 
35 struct inet_peer {
36 	struct rb_node		rb_node;
37 	struct inetpeer_addr	daddr;
38 
39 	u32			metrics[RTAX_MAX];
40 	u32			rate_tokens;	/* rate limiting for ICMP */
41 	unsigned long		rate_last;
42 	/*
43 	 * Once inet_peer is queued for deletion (refcnt == 0), following field
44 	 * is not available: rid
45 	 * We can share memory with rcu_head to help keep inet_peer small.
46 	 */
47 	union {
48 		struct {
49 			atomic_t			rid;		/* Frag reception counter */
50 		};
51 		struct rcu_head         rcu;
52 	};
53 
54 	/* following fields might be frequently dirtied */
55 	__u32			dtime;	/* the time of last use of not referenced entries */
56 	refcount_t		refcnt;
57 };
58 
59 struct inet_peer_base {
60 	struct rb_root		rb_root;
61 	seqlock_t		lock;
62 	int			total;
63 };
64 
65 void inet_peer_base_init(struct inet_peer_base *);
66 
67 void inet_initpeers(void) __init;
68 
69 #define INETPEER_METRICS_NEW	(~(u32) 0)
70 
71 static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip)
72 {
73 	iaddr->a4.addr = ip;
74 	iaddr->a4.vif = 0;
75 	iaddr->family = AF_INET;
76 }
77 
78 static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr)
79 {
80 	return iaddr->a4.addr;
81 }
82 
83 static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr,
84 					struct in6_addr *in6)
85 {
86 	iaddr->a6 = *in6;
87 	iaddr->family = AF_INET6;
88 }
89 
90 static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr)
91 {
92 	return &iaddr->a6;
93 }
94 
95 /* can be called with or without local BH being disabled */
96 struct inet_peer *inet_getpeer(struct inet_peer_base *base,
97 			       const struct inetpeer_addr *daddr,
98 			       int create);
99 
100 static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
101 						__be32 v4daddr,
102 						int vif, int create)
103 {
104 	struct inetpeer_addr daddr;
105 
106 	daddr.a4.addr = v4daddr;
107 	daddr.a4.vif = vif;
108 	daddr.family = AF_INET;
109 	return inet_getpeer(base, &daddr, create);
110 }
111 
112 static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
113 						const struct in6_addr *v6daddr,
114 						int create)
115 {
116 	struct inetpeer_addr daddr;
117 
118 	daddr.a6 = *v6daddr;
119 	daddr.family = AF_INET6;
120 	return inet_getpeer(base, &daddr, create);
121 }
122 
123 static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a,
124 				    const struct inetpeer_addr *b)
125 {
126 	int i, n;
127 
128 	if (a->family == AF_INET)
129 		n = sizeof(a->a4) / sizeof(u32);
130 	else
131 		n = sizeof(a->a6) / sizeof(u32);
132 
133 	for (i = 0; i < n; i++) {
134 		if (a->key[i] == b->key[i])
135 			continue;
136 		if (a->key[i] < b->key[i])
137 			return -1;
138 		return 1;
139 	}
140 
141 	return 0;
142 }
143 
144 /* can be called from BH context or outside */
145 void inet_putpeer(struct inet_peer *p);
146 bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
147 
148 void inetpeer_invalidate_tree(struct inet_peer_base *);
149 
150 #endif /* _NET_INETPEER_H */
151