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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/jhash.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
struct nft_hash {
struct hlist_head *hash;
unsigned int hsize;
};
struct nft_hash_elem {
struct hlist_node hnode;
struct nft_data key;
struct nft_data data[];
};
static u32 nft_hash_rnd __read_mostly;
static bool nft_hash_rnd_initted __read_mostly;
static unsigned int nft_hash_data(const struct nft_data *data,
unsigned int hsize, unsigned int len)
{
unsigned int h;
h = jhash(data->data, len, nft_hash_rnd);
return ((u64)h * hsize) >> 32;
}
static bool nft_hash_lookup(const struct nft_set *set,
const struct nft_data *key,
struct nft_data *data)
{
const struct nft_hash *priv = nft_set_priv(set);
const struct nft_hash_elem *he;
unsigned int h;
h = nft_hash_data(key, priv->hsize, set->klen);
hlist_for_each_entry(he, &priv->hash[h], hnode) {
if (nft_data_cmp(&he->key, key, set->klen))
continue;
if (set->flags & NFT_SET_MAP)
nft_data_copy(data, he->data);
return true;
}
return false;
}
static void nft_hash_elem_destroy(const struct nft_set *set,
struct nft_hash_elem *he)
{
nft_data_uninit(&he->key, NFT_DATA_VALUE);
if (set->flags & NFT_SET_MAP)
nft_data_uninit(he->data, set->dtype);
kfree(he);
}
static int nft_hash_insert(const struct nft_set *set,
const struct nft_set_elem *elem)
{
struct nft_hash *priv = nft_set_priv(set);
struct nft_hash_elem *he;
unsigned int size, h;
if (elem->flags != 0)
return -EINVAL;
size = sizeof(*he);
if (set->flags & NFT_SET_MAP)
size += sizeof(he->data[0]);
he = kzalloc(size, GFP_KERNEL);
if (he == NULL)
return -ENOMEM;
nft_data_copy(&he->key, &elem->key);
if (set->flags & NFT_SET_MAP)
nft_data_copy(he->data, &elem->data);
h = nft_hash_data(&he->key, priv->hsize, set->klen);
hlist_add_head_rcu(&he->hnode, &priv->hash[h]);
return 0;
}
static void nft_hash_remove(const struct nft_set *set,
const struct nft_set_elem *elem)
{
struct nft_hash_elem *he = elem->cookie;
hlist_del_rcu(&he->hnode);
kfree(he);
}
static int nft_hash_get(const struct nft_set *set, struct nft_set_elem *elem)
{
const struct nft_hash *priv = nft_set_priv(set);
struct nft_hash_elem *he;
unsigned int h;
h = nft_hash_data(&elem->key, priv->hsize, set->klen);
hlist_for_each_entry(he, &priv->hash[h], hnode) {
if (nft_data_cmp(&he->key, &elem->key, set->klen))
continue;
elem->cookie = he;
elem->flags = 0;
if (set->flags & NFT_SET_MAP)
nft_data_copy(&elem->data, he->data);
return 0;
}
return -ENOENT;
}
static void nft_hash_walk(const struct nft_ctx *ctx, const struct nft_set *set,
struct nft_set_iter *iter)
{
const struct nft_hash *priv = nft_set_priv(set);
const struct nft_hash_elem *he;
struct nft_set_elem elem;
unsigned int i;
for (i = 0; i < priv->hsize; i++) {
hlist_for_each_entry(he, &priv->hash[i], hnode) {
if (iter->count < iter->skip)
goto cont;
memcpy(&elem.key, &he->key, sizeof(elem.key));
if (set->flags & NFT_SET_MAP)
memcpy(&elem.data, he->data, sizeof(elem.data));
elem.flags = 0;
iter->err = iter->fn(ctx, set, iter, &elem);
if (iter->err < 0)
return;
cont:
iter->count++;
}
}
}
static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
{
return sizeof(struct nft_hash);
}
static int nft_hash_init(const struct nft_set *set,
const struct nlattr * const tb[])
{
struct nft_hash *priv = nft_set_priv(set);
unsigned int cnt, i;
if (unlikely(!nft_hash_rnd_initted)) {
get_random_bytes(&nft_hash_rnd, 4);
nft_hash_rnd_initted = true;
}
/* Aim for a load factor of 0.75 */
// FIXME: temporarily broken until we have set descriptions
cnt = 100;
cnt = cnt * 4 / 3;
priv->hash = kcalloc(cnt, sizeof(struct hlist_head), GFP_KERNEL);
if (priv->hash == NULL)
return -ENOMEM;
priv->hsize = cnt;
for (i = 0; i < cnt; i++)
INIT_HLIST_HEAD(&priv->hash[i]);
return 0;
}
static void nft_hash_destroy(const struct nft_set *set)
{
const struct nft_hash *priv = nft_set_priv(set);
const struct hlist_node *next;
struct nft_hash_elem *elem;
unsigned int i;
for (i = 0; i < priv->hsize; i++) {
hlist_for_each_entry_safe(elem, next, &priv->hash[i], hnode) {
hlist_del(&elem->hnode);
nft_hash_elem_destroy(set, elem);
}
}
kfree(priv->hash);
}
static struct nft_set_ops nft_hash_ops __read_mostly = {
.privsize = nft_hash_privsize,
.init = nft_hash_init,
.destroy = nft_hash_destroy,
.get = nft_hash_get,
.insert = nft_hash_insert,
.remove = nft_hash_remove,
.lookup = nft_hash_lookup,
.walk = nft_hash_walk,
.features = NFT_SET_MAP,
.owner = THIS_MODULE,
};
static int __init nft_hash_module_init(void)
{
return nft_register_set(&nft_hash_ops);
}
static void __exit nft_hash_module_exit(void)
{
nft_unregister_set(&nft_hash_ops);
}
module_init(nft_hash_module_init);
module_exit(nft_hash_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_SET();
|
