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 u64 hash;
39 struct inetpeer_addr daddr;
40
41 u32 metrics[RTAX_MAX];
42 u32 rate_tokens; /* rate limiting for ICMP */
43 u32 n_redirects;
44 unsigned long rate_last;
45 /*
46 * Once inet_peer is queued for deletion (refcnt == 0), following field
47 * is not available: rid
48 * We can share memory with rcu_head to help keep inet_peer small.
49 */
50 union {
51 struct {
52 atomic_t rid; /* Frag reception counter */
53 };
54 struct rcu_head rcu;
55 };
56
57 /* following fields might be frequently dirtied */
58 __u32 dtime; /* the time of last use of not referenced entries */
59 refcount_t refcnt;
60 };
61
62 struct inet_peer_base {
63 struct rb_root rb_root;
64 seqlock_t lock;
65 int total;
66 };
67
68 void inet_peer_base_init(struct inet_peer_base *);
69
70 void inet_initpeers(void) __init;
71
72 #define INETPEER_METRICS_NEW (~(u32) 0)
73
inetpeer_set_addr_v4(struct inetpeer_addr * iaddr,__be32 ip)74 static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip)
75 {
76 iaddr->a4.addr = ip;
77 iaddr->a4.vif = 0;
78 iaddr->family = AF_INET;
79 }
80
inetpeer_get_addr_v4(struct inetpeer_addr * iaddr)81 static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr)
82 {
83 return iaddr->a4.addr;
84 }
85
inetpeer_set_addr_v6(struct inetpeer_addr * iaddr,struct in6_addr * in6)86 static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr,
87 struct in6_addr *in6)
88 {
89 iaddr->a6 = *in6;
90 iaddr->family = AF_INET6;
91 }
92
inetpeer_get_addr_v6(struct inetpeer_addr * iaddr)93 static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr)
94 {
95 return &iaddr->a6;
96 }
97
98 /* can be called with or without local BH being disabled */
99 struct inet_peer *inet_getpeer(struct inet_peer_base *base,
100 const struct inetpeer_addr *daddr);
101
inet_getpeer_v4(struct inet_peer_base * base,__be32 v4daddr,int vif)102 static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
103 __be32 v4daddr,
104 int vif)
105 {
106 struct inetpeer_addr daddr;
107
108 daddr.a4.addr = v4daddr;
109 daddr.a4.vif = vif;
110 daddr.family = AF_INET;
111 return inet_getpeer(base, &daddr);
112 }
113
inet_getpeer_v6(struct inet_peer_base * base,const struct in6_addr * v6daddr)114 static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
115 const struct in6_addr *v6daddr)
116 {
117 struct inetpeer_addr daddr;
118
119 daddr.a6 = *v6daddr;
120 daddr.family = AF_INET6;
121 return inet_getpeer(base, &daddr);
122 }
123
inetpeer_addr_cmp(const struct inetpeer_addr * a,const struct inetpeer_addr * b)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 != b->family)
130 return a->family < b->family ? -1 : 1;
131
132 if (a->family == AF_INET)
133 n = sizeof(a->a4) / sizeof(u32);
134 else
135 n = sizeof(a->a6) / sizeof(u32);
136
137 for (i = 0; i < n; i++) {
138 if (a->key[i] == b->key[i])
139 continue;
140 if (a->key[i] < b->key[i])
141 return -1;
142 return 1;
143 }
144
145 return 0;
146 }
147
148 /* can be called from BH context or outside */
149 void inet_putpeer(struct inet_peer *p);
150 bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
151
152 void inetpeer_invalidate_tree(struct inet_peer_base *);
153
154 #endif /* _NET_INETPEER_H */
155