xref: /openbmc/linux/include/net/inetpeer.h (revision 6d99a79c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *		INETPEER - A storage for permanent information about peers
4  *
5  *  Authors:	Andrey V. Savochkin <saw@msu.ru>
6  */
7 
8 #ifndef _NET_INETPEER_H
9 #define _NET_INETPEER_H
10 
11 #include <linux/types.h>
12 #include <linux/init.h>
13 #include <linux/jiffies.h>
14 #include <linux/spinlock.h>
15 #include <linux/rtnetlink.h>
16 #include <net/ipv6.h>
17 #include <linux/atomic.h>
18 
19 /* IPv4 address key for cache lookups */
20 struct ipv4_addr_key {
21 	__be32	addr;
22 	int	vif;
23 };
24 
25 #define INETPEER_MAXKEYSZ   (sizeof(struct in6_addr) / sizeof(u32))
26 
27 struct inetpeer_addr {
28 	union {
29 		struct ipv4_addr_key	a4;
30 		struct in6_addr		a6;
31 		u32			key[INETPEER_MAXKEYSZ];
32 	};
33 	__u16				family;
34 };
35 
36 struct inet_peer {
37 	struct rb_node		rb_node;
38 	struct inetpeer_addr	daddr;
39 
40 	u32			metrics[RTAX_MAX];
41 	u32			rate_tokens;	/* rate limiting for ICMP */
42 	unsigned long		rate_last;
43 	/*
44 	 * Once inet_peer is queued for deletion (refcnt == 0), following field
45 	 * is not available: rid
46 	 * We can share memory with rcu_head to help keep inet_peer small.
47 	 */
48 	union {
49 		struct {
50 			atomic_t			rid;		/* Frag reception counter */
51 		};
52 		struct rcu_head         rcu;
53 	};
54 
55 	/* following fields might be frequently dirtied */
56 	__u32			dtime;	/* the time of last use of not referenced entries */
57 	refcount_t		refcnt;
58 };
59 
60 struct inet_peer_base {
61 	struct rb_root		rb_root;
62 	seqlock_t		lock;
63 	int			total;
64 };
65 
66 void inet_peer_base_init(struct inet_peer_base *);
67 
68 void inet_initpeers(void) __init;
69 
70 #define INETPEER_METRICS_NEW	(~(u32) 0)
71 
72 static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip)
73 {
74 	iaddr->a4.addr = ip;
75 	iaddr->a4.vif = 0;
76 	iaddr->family = AF_INET;
77 }
78 
79 static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr)
80 {
81 	return iaddr->a4.addr;
82 }
83 
84 static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr,
85 					struct in6_addr *in6)
86 {
87 	iaddr->a6 = *in6;
88 	iaddr->family = AF_INET6;
89 }
90 
91 static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr)
92 {
93 	return &iaddr->a6;
94 }
95 
96 /* can be called with or without local BH being disabled */
97 struct inet_peer *inet_getpeer(struct inet_peer_base *base,
98 			       const struct inetpeer_addr *daddr,
99 			       int create);
100 
101 static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
102 						__be32 v4daddr,
103 						int vif, int create)
104 {
105 	struct inetpeer_addr daddr;
106 
107 	daddr.a4.addr = v4daddr;
108 	daddr.a4.vif = vif;
109 	daddr.family = AF_INET;
110 	return inet_getpeer(base, &daddr, create);
111 }
112 
113 static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
114 						const struct in6_addr *v6daddr,
115 						int create)
116 {
117 	struct inetpeer_addr daddr;
118 
119 	daddr.a6 = *v6daddr;
120 	daddr.family = AF_INET6;
121 	return inet_getpeer(base, &daddr, create);
122 }
123 
124 static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a,
125 				    const struct inetpeer_addr *b)
126 {
127 	int i, n;
128 
129 	if (a->family == AF_INET)
130 		n = sizeof(a->a4) / sizeof(u32);
131 	else
132 		n = sizeof(a->a6) / sizeof(u32);
133 
134 	for (i = 0; i < n; i++) {
135 		if (a->key[i] == b->key[i])
136 			continue;
137 		if (a->key[i] < b->key[i])
138 			return -1;
139 		return 1;
140 	}
141 
142 	return 0;
143 }
144 
145 /* can be called from BH context or outside */
146 void inet_putpeer(struct inet_peer *p);
147 bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
148 
149 void inetpeer_invalidate_tree(struct inet_peer_base *);
150 
151 #endif /* _NET_INETPEER_H */
152