aboutsummaryrefslogtreecommitdiffstats
path: root/net/xfrm/xfrm_hash.h
blob: 0622d319e1f269c31e8a6af27e4c986832948534 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
#ifndef _XFRM_HASH_H
#define _XFRM_HASH_H

#include <linux/xfrm.h>
#include <linux/socket.h>

static inline unsigned int __xfrm4_addr_hash(const xfrm_address_t *addr)
{
	return ntohl(addr->a4);
}

static inline unsigned int __xfrm6_addr_hash(const xfrm_address_t *addr)
{
	return ntohl(addr->a6[2] ^ addr->a6[3]);
}

static inline unsigned int __xfrm4_daddr_saddr_hash(const xfrm_address_t *daddr,
						    const xfrm_address_t *saddr)
{
	u32 sum = (__force u32)daddr->a4 + (__force u32)saddr->a4;
	return ntohl((__force __be32)sum);
}

static inline unsigned int __xfrm6_daddr_saddr_hash(const xfrm_address_t *daddr,
						    const xfrm_address_t *saddr)
{
	return ntohl(daddr->a6[2] ^ daddr->a6[3] ^
		     saddr->a6[2] ^ saddr->a6[3]);
}

static inline unsigned int __xfrm_dst_hash(const xfrm_address_t *daddr,
					   const xfrm_address_t *saddr,
					   u32 reqid, unsigned short family,
					   unsigned int hmask)
{
	unsigned int h = family ^ reqid;
	switch (family) {
	case AF_INET:
		h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
		break;
	case AF_INET6:
		h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
		break;
	}
	return (h ^ (h >> 16)) & hmask;
}

static inline unsigned int __xfrm_src_hash(const xfrm_address_t *daddr,
					   const xfrm_address_t *saddr,
					   unsigned short family,
					   unsigned int hmask)
{
	unsigned int h = family;
	switch (family) {
	case AF_INET:
		h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
		break;
	case AF_INET6:
		h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
		break;
	}
	return (h ^ (h >> 16)) & hmask;
}

static inline unsigned int
__xfrm_spi_hash(const xfrm_address_t *daddr, __be32 spi, u8 proto,
		unsigned short family, unsigned int hmask)
{
	unsigned int h = (__force u32)spi ^ proto;
	switch (family) {
	case AF_INET:
		h ^= __xfrm4_addr_hash(daddr);
		break;
	case AF_INET6:
		h ^= __xfrm6_addr_hash(daddr);
		break;
	}
	return (h ^ (h >> 10) ^ (h >> 20)) & hmask;
}

static inline unsigned int __idx_hash(u32 index, unsigned int hmask)
{
	return (index ^ (index >> 8)) & hmask;
}

static inline unsigned int __sel_hash(const struct xfrm_selector *sel,
				      unsigned short family, unsigned int hmask)
{
	const xfrm_address_t *daddr = &sel->daddr;
	const xfrm_address_t *saddr = &sel->saddr;
	unsigned int h = 0;

	switch (family) {
	case AF_INET:
		if (sel->prefixlen_d != 32 ||
		    sel->prefixlen_s != 32)
			return hmask + 1;

		h = __xfrm4_daddr_saddr_hash(daddr, saddr);
		break;

	case AF_INET6:
		if (sel->prefixlen_d != 128 ||
		    sel->prefixlen_s != 128)
			return hmask + 1;

		h = __xfrm6_daddr_saddr_hash(daddr, saddr);
		break;
	}
	h ^= (h >> 16);
	return h & hmask;
}

static inline unsigned int __addr_hash(const xfrm_address_t *daddr,
				       const xfrm_address_t *saddr,
				       unsigned short family, unsigned int hmask)
{
	unsigned int h = 0;

	switch (family) {
	case AF_INET:
		h = __xfrm4_daddr_saddr_hash(daddr, saddr);
		break;

	case AF_INET6:
		h = __xfrm6_daddr_saddr_hash(daddr, saddr);
		break;
	}
	h ^= (h >> 16);
	return h & hmask;
}

struct hlist_head *xfrm_hash_alloc(unsigned int sz);
void xfrm_hash_free(struct hlist_head *n, unsigned int sz);

#endif /* _XFRM_HASH_H */