1 /*
2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * Development of this code funded by Astaro AG (http://www.astaro.com/)
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/list.h>
15 #include <linux/rbtree.h>
16 #include <linux/netlink.h>
17 #include <linux/netfilter.h>
18 #include <linux/netfilter/nf_tables.h>
19 #include <net/netfilter/nf_tables.h>
20
21 static DEFINE_SPINLOCK(nft_rbtree_lock);
22
23 struct nft_rbtree {
24 struct rb_root root;
25 };
26
27 struct nft_rbtree_elem {
28 struct rb_node node;
29 u16 flags;
30 struct nft_data key;
31 struct nft_data data[];
32 };
33
nft_rbtree_lookup(const struct nft_set * set,const struct nft_data * key,struct nft_data * data)34 static bool nft_rbtree_lookup(const struct nft_set *set,
35 const struct nft_data *key,
36 struct nft_data *data)
37 {
38 const struct nft_rbtree *priv = nft_set_priv(set);
39 const struct nft_rbtree_elem *rbe, *interval = NULL;
40 const struct rb_node *parent = priv->root.rb_node;
41 int d;
42
43 spin_lock_bh(&nft_rbtree_lock);
44 while (parent != NULL) {
45 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
46
47 d = nft_data_cmp(&rbe->key, key, set->klen);
48 if (d < 0) {
49 parent = parent->rb_left;
50 interval = rbe;
51 } else if (d > 0)
52 parent = parent->rb_right;
53 else {
54 found:
55 if (rbe->flags & NFT_SET_ELEM_INTERVAL_END)
56 goto out;
57 if (set->flags & NFT_SET_MAP)
58 nft_data_copy(data, rbe->data);
59
60 spin_unlock_bh(&nft_rbtree_lock);
61 return true;
62 }
63 }
64
65 if (set->flags & NFT_SET_INTERVAL && interval != NULL) {
66 rbe = interval;
67 goto found;
68 }
69 out:
70 spin_unlock_bh(&nft_rbtree_lock);
71 return false;
72 }
73
nft_rbtree_elem_destroy(const struct nft_set * set,struct nft_rbtree_elem * rbe)74 static void nft_rbtree_elem_destroy(const struct nft_set *set,
75 struct nft_rbtree_elem *rbe)
76 {
77 nft_data_uninit(&rbe->key, NFT_DATA_VALUE);
78 if (set->flags & NFT_SET_MAP &&
79 !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
80 nft_data_uninit(rbe->data, set->dtype);
81
82 kfree(rbe);
83 }
84
__nft_rbtree_insert(const struct nft_set * set,struct nft_rbtree_elem * new)85 static int __nft_rbtree_insert(const struct nft_set *set,
86 struct nft_rbtree_elem *new)
87 {
88 struct nft_rbtree *priv = nft_set_priv(set);
89 struct nft_rbtree_elem *rbe;
90 struct rb_node *parent, **p;
91 int d;
92
93 parent = NULL;
94 p = &priv->root.rb_node;
95 while (*p != NULL) {
96 parent = *p;
97 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
98 d = nft_data_cmp(&rbe->key, &new->key, set->klen);
99 if (d < 0)
100 p = &parent->rb_left;
101 else if (d > 0)
102 p = &parent->rb_right;
103 else
104 return -EEXIST;
105 }
106 rb_link_node(&new->node, parent, p);
107 rb_insert_color(&new->node, &priv->root);
108 return 0;
109 }
110
nft_rbtree_insert(const struct nft_set * set,const struct nft_set_elem * elem)111 static int nft_rbtree_insert(const struct nft_set *set,
112 const struct nft_set_elem *elem)
113 {
114 struct nft_rbtree_elem *rbe;
115 unsigned int size;
116 int err;
117
118 size = sizeof(*rbe);
119 if (set->flags & NFT_SET_MAP &&
120 !(elem->flags & NFT_SET_ELEM_INTERVAL_END))
121 size += sizeof(rbe->data[0]);
122
123 rbe = kzalloc(size, GFP_KERNEL);
124 if (rbe == NULL)
125 return -ENOMEM;
126
127 rbe->flags = elem->flags;
128 nft_data_copy(&rbe->key, &elem->key);
129 if (set->flags & NFT_SET_MAP &&
130 !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
131 nft_data_copy(rbe->data, &elem->data);
132
133 spin_lock_bh(&nft_rbtree_lock);
134 err = __nft_rbtree_insert(set, rbe);
135 if (err < 0)
136 kfree(rbe);
137
138 spin_unlock_bh(&nft_rbtree_lock);
139 return err;
140 }
141
nft_rbtree_remove(const struct nft_set * set,const struct nft_set_elem * elem)142 static void nft_rbtree_remove(const struct nft_set *set,
143 const struct nft_set_elem *elem)
144 {
145 struct nft_rbtree *priv = nft_set_priv(set);
146 struct nft_rbtree_elem *rbe = elem->cookie;
147
148 spin_lock_bh(&nft_rbtree_lock);
149 rb_erase(&rbe->node, &priv->root);
150 spin_unlock_bh(&nft_rbtree_lock);
151 kfree(rbe);
152 }
153
nft_rbtree_get(const struct nft_set * set,struct nft_set_elem * elem)154 static int nft_rbtree_get(const struct nft_set *set, struct nft_set_elem *elem)
155 {
156 const struct nft_rbtree *priv = nft_set_priv(set);
157 const struct rb_node *parent = priv->root.rb_node;
158 struct nft_rbtree_elem *rbe;
159 int d;
160
161 spin_lock_bh(&nft_rbtree_lock);
162 while (parent != NULL) {
163 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
164
165 d = nft_data_cmp(&rbe->key, &elem->key, set->klen);
166 if (d < 0)
167 parent = parent->rb_left;
168 else if (d > 0)
169 parent = parent->rb_right;
170 else {
171 elem->cookie = rbe;
172 if (set->flags & NFT_SET_MAP &&
173 !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
174 nft_data_copy(&elem->data, rbe->data);
175 elem->flags = rbe->flags;
176 spin_unlock_bh(&nft_rbtree_lock);
177 return 0;
178 }
179 }
180 spin_unlock_bh(&nft_rbtree_lock);
181 return -ENOENT;
182 }
183
nft_rbtree_walk(const struct nft_ctx * ctx,const struct nft_set * set,struct nft_set_iter * iter)184 static void nft_rbtree_walk(const struct nft_ctx *ctx,
185 const struct nft_set *set,
186 struct nft_set_iter *iter)
187 {
188 const struct nft_rbtree *priv = nft_set_priv(set);
189 const struct nft_rbtree_elem *rbe;
190 struct nft_set_elem elem;
191 struct rb_node *node;
192
193 spin_lock_bh(&nft_rbtree_lock);
194 for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
195 if (iter->count < iter->skip)
196 goto cont;
197
198 rbe = rb_entry(node, struct nft_rbtree_elem, node);
199 nft_data_copy(&elem.key, &rbe->key);
200 if (set->flags & NFT_SET_MAP &&
201 !(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
202 nft_data_copy(&elem.data, rbe->data);
203 elem.flags = rbe->flags;
204
205 iter->err = iter->fn(ctx, set, iter, &elem);
206 if (iter->err < 0) {
207 spin_unlock_bh(&nft_rbtree_lock);
208 return;
209 }
210 cont:
211 iter->count++;
212 }
213 spin_unlock_bh(&nft_rbtree_lock);
214 }
215
nft_rbtree_privsize(const struct nlattr * const nla[])216 static unsigned int nft_rbtree_privsize(const struct nlattr * const nla[])
217 {
218 return sizeof(struct nft_rbtree);
219 }
220
nft_rbtree_init(const struct nft_set * set,const struct nft_set_desc * desc,const struct nlattr * const nla[])221 static int nft_rbtree_init(const struct nft_set *set,
222 const struct nft_set_desc *desc,
223 const struct nlattr * const nla[])
224 {
225 struct nft_rbtree *priv = nft_set_priv(set);
226
227 priv->root = RB_ROOT;
228 return 0;
229 }
230
nft_rbtree_destroy(const struct nft_set * set)231 static void nft_rbtree_destroy(const struct nft_set *set)
232 {
233 struct nft_rbtree *priv = nft_set_priv(set);
234 struct nft_rbtree_elem *rbe;
235 struct rb_node *node;
236
237 while ((node = priv->root.rb_node) != NULL) {
238 rb_erase(node, &priv->root);
239 rbe = rb_entry(node, struct nft_rbtree_elem, node);
240 nft_rbtree_elem_destroy(set, rbe);
241 }
242 }
243
nft_rbtree_estimate(const struct nft_set_desc * desc,u32 features,struct nft_set_estimate * est)244 static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
245 struct nft_set_estimate *est)
246 {
247 unsigned int nsize;
248
249 nsize = sizeof(struct nft_rbtree_elem);
250 if (features & NFT_SET_MAP)
251 nsize += FIELD_SIZEOF(struct nft_rbtree_elem, data[0]);
252
253 if (desc->size)
254 est->size = sizeof(struct nft_rbtree) + desc->size * nsize;
255 else
256 est->size = nsize;
257
258 est->class = NFT_SET_CLASS_O_LOG_N;
259
260 return true;
261 }
262
263 static struct nft_set_ops nft_rbtree_ops __read_mostly = {
264 .privsize = nft_rbtree_privsize,
265 .estimate = nft_rbtree_estimate,
266 .init = nft_rbtree_init,
267 .destroy = nft_rbtree_destroy,
268 .insert = nft_rbtree_insert,
269 .remove = nft_rbtree_remove,
270 .get = nft_rbtree_get,
271 .lookup = nft_rbtree_lookup,
272 .walk = nft_rbtree_walk,
273 .features = NFT_SET_INTERVAL | NFT_SET_MAP,
274 .owner = THIS_MODULE,
275 };
276
nft_rbtree_module_init(void)277 static int __init nft_rbtree_module_init(void)
278 {
279 return nft_register_set(&nft_rbtree_ops);
280 }
281
nft_rbtree_module_exit(void)282 static void __exit nft_rbtree_module_exit(void)
283 {
284 nft_unregister_set(&nft_rbtree_ops);
285 }
286
287 module_init(nft_rbtree_module_init);
288 module_exit(nft_rbtree_module_exit);
289
290 MODULE_LICENSE("GPL");
291 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
292 MODULE_ALIAS_NFT_SET();
293