aboutsummaryrefslogtreecommitdiffstats
path: root/net/xfrm/xfrm_hash.h
blob: d3abb0b7dc62190259c941fb28cdfc068d32c1df (plain)
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
#ifndef _XFRM_HASH_H
#define _XFRM_HASH_H

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

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

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

static inline unsigned int __xfrm4_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
{
	return ntohl(daddr->a4 ^ saddr->a4);
}

static inline unsigned int __xfrm6_daddr_saddr_hash(xfrm_address_t *daddr, 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(xfrm_address_t *daddr, 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 __xfrm_src_hash(xfrm_address_t *saddr,
				       unsigned short family,
				       unsigned int hmask)
{
	unsigned int h = family;
	switch (family) {
	case AF_INET:
		h ^= __xfrm4_addr_hash(saddr);
		break;
	case AF_INET6:
		h ^= __xfrm6_addr_hash(saddr);
		break;
	};
	return (h ^ (h >> 16)) & hmask;
}

static inline unsigned int
__xfrm_spi_hash(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family,
		unsigned int hmask)
{
	unsigned int h = 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(struct xfrm_selector *sel, unsigned short family, unsigned int hmask)
{
	xfrm_address_t *daddr = &sel->daddr;
	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(xfrm_address_t *daddr, 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;
}

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

#endif /* _XFRM_HASH_H */