1109998Smarkm/* SPDX-License-Identifier: GPL-2.0 */
2109998Smarkm/*
3109998Smarkm *		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 */
20struct ipv4_addr_key {
21	__be32	addr;
22	int	vif;
23};
24
25#define INETPEER_MAXKEYSZ   (sizeof(struct in6_addr) / sizeof(u32))
26
27struct 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
36struct 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	u32			n_redirects;
43	unsigned long		rate_last;
44	/*
45	 * Once inet_peer is queued for deletion (refcnt == 0), following field
46	 * is not available: rid
47	 * We can share memory with rcu_head to help keep inet_peer small.
48	 */
49	union {
50		struct {
51			atomic_t			rid;		/* Frag reception counter */
52		};
53		struct rcu_head         rcu;
54	};
55
56	/* following fields might be frequently dirtied */
57	__u32			dtime;	/* the time of last use of not referenced entries */
58	refcount_t		refcnt;
59};
60
61struct inet_peer_base {
62	struct rb_root		rb_root;
63	seqlock_t		lock;
64	int			total;
65};
66
67void inet_peer_base_init(struct inet_peer_base *);
68
69void inet_initpeers(void) __init;
70
71#define INETPEER_METRICS_NEW	(~(u32) 0)
72
73static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip)
74{
75	iaddr->a4.addr = ip;
76	iaddr->a4.vif = 0;
77	iaddr->family = AF_INET;
78}
79
80static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr)
81{
82	return iaddr->a4.addr;
83}
84
85static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr,
86					struct in6_addr *in6)
87{
88	iaddr->a6 = *in6;
89	iaddr->family = AF_INET6;
90}
91
92static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr)
93{
94	return &iaddr->a6;
95}
96
97/* can be called with or without local BH being disabled */
98struct inet_peer *inet_getpeer(struct inet_peer_base *base,
99			       const struct inetpeer_addr *daddr,
100			       int create);
101
102static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
103						__be32 v4daddr,
104						int vif, int create)
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, create);
112}
113
114static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
115						const struct in6_addr *v6daddr,
116						int create)
117{
118	struct inetpeer_addr daddr;
119
120	daddr.a6 = *v6daddr;
121	daddr.family = AF_INET6;
122	return inet_getpeer(base, &daddr, create);
123}
124
125static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a,
126				    const struct inetpeer_addr *b)
127{
128	int i, n;
129
130	if (a->family == AF_INET)
131		n = sizeof(a->a4) / sizeof(u32);
132	else
133		n = sizeof(a->a6) / sizeof(u32);
134
135	for (i = 0; i < n; i++) {
136		if (a->key[i] == b->key[i])
137			continue;
138		if (a->key[i] < b->key[i])
139			return -1;
140		return 1;
141	}
142
143	return 0;
144}
145
146/* can be called from BH context or outside */
147void inet_putpeer(struct inet_peer *p);
148bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
149
150void inetpeer_invalidate_tree(struct inet_peer_base *);
151
152#endif /* _NET_INETPEER_H */
153