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 struct nft_set_ext ext;
30 };
31
32
nft_rbtree_lookup(const struct nft_set * set,const u32 * key,const struct nft_set_ext ** ext)33 static bool nft_rbtree_lookup(const struct nft_set *set, const u32 *key,
34 const struct nft_set_ext **ext)
35 {
36 const struct nft_rbtree *priv = nft_set_priv(set);
37 const struct nft_rbtree_elem *rbe, *interval = NULL;
38 const struct rb_node *parent;
39 u8 genmask = nft_genmask_cur(read_pnet(&set->pnet));
40 int d;
41
42 spin_lock_bh(&nft_rbtree_lock);
43 parent = priv->root.rb_node;
44 while (parent != NULL) {
45 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
46
47 d = memcmp(nft_set_ext_key(&rbe->ext), 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 (!nft_set_elem_active(&rbe->ext, genmask)) {
56 parent = parent->rb_left;
57 continue;
58 }
59 if (nft_set_ext_exists(&rbe->ext, NFT_SET_EXT_FLAGS) &&
60 *nft_set_ext_flags(&rbe->ext) &
61 NFT_SET_ELEM_INTERVAL_END)
62 goto out;
63 spin_unlock_bh(&nft_rbtree_lock);
64
65 *ext = &rbe->ext;
66 return true;
67 }
68 }
69
70 if (set->flags & NFT_SET_INTERVAL && interval != NULL) {
71 rbe = interval;
72 goto found;
73 }
74 out:
75 spin_unlock_bh(&nft_rbtree_lock);
76 return false;
77 }
78
__nft_rbtree_insert(const struct nft_set * set,struct nft_rbtree_elem * new)79 static int __nft_rbtree_insert(const struct nft_set *set,
80 struct nft_rbtree_elem *new)
81 {
82 struct nft_rbtree *priv = nft_set_priv(set);
83 struct nft_rbtree_elem *rbe;
84 struct rb_node *parent, **p;
85 u8 genmask = nft_genmask_next(read_pnet(&set->pnet));
86 int d;
87
88 parent = NULL;
89 p = &priv->root.rb_node;
90 while (*p != NULL) {
91 parent = *p;
92 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
93 d = memcmp(nft_set_ext_key(&rbe->ext),
94 nft_set_ext_key(&new->ext),
95 set->klen);
96 if (d < 0)
97 p = &parent->rb_left;
98 else if (d > 0)
99 p = &parent->rb_right;
100 else {
101 if (nft_set_elem_active(&rbe->ext, genmask))
102 return -EEXIST;
103 p = &parent->rb_left;
104 }
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 = elem->priv;
115 int err;
116
117 spin_lock_bh(&nft_rbtree_lock);
118 err = __nft_rbtree_insert(set, rbe);
119 spin_unlock_bh(&nft_rbtree_lock);
120
121 return err;
122 }
123
nft_rbtree_remove(const struct nft_set * set,const struct nft_set_elem * elem)124 static void nft_rbtree_remove(const struct nft_set *set,
125 const struct nft_set_elem *elem)
126 {
127 struct nft_rbtree *priv = nft_set_priv(set);
128 struct nft_rbtree_elem *rbe = elem->priv;
129
130 spin_lock_bh(&nft_rbtree_lock);
131 rb_erase(&rbe->node, &priv->root);
132 spin_unlock_bh(&nft_rbtree_lock);
133 }
134
nft_rbtree_activate(const struct nft_set * set,const struct nft_set_elem * elem)135 static void nft_rbtree_activate(const struct nft_set *set,
136 const struct nft_set_elem *elem)
137 {
138 struct nft_rbtree_elem *rbe = elem->priv;
139
140 nft_set_elem_change_active(set, &rbe->ext);
141 }
142
nft_rbtree_deactivate(const struct nft_set * set,const struct nft_set_elem * elem)143 static void *nft_rbtree_deactivate(const struct nft_set *set,
144 const struct nft_set_elem *elem)
145 {
146 const struct nft_rbtree *priv = nft_set_priv(set);
147 const struct rb_node *parent = priv->root.rb_node;
148 struct nft_rbtree_elem *rbe;
149 u8 genmask = nft_genmask_cur(read_pnet(&set->pnet));
150 int d;
151
152 while (parent != NULL) {
153 rbe = rb_entry(parent, struct nft_rbtree_elem, node);
154
155 d = memcmp(nft_set_ext_key(&rbe->ext), &elem->key.val,
156 set->klen);
157 if (d < 0)
158 parent = parent->rb_left;
159 else if (d > 0)
160 parent = parent->rb_right;
161 else {
162 if (!nft_set_elem_active(&rbe->ext, genmask)) {
163 parent = parent->rb_left;
164 continue;
165 }
166 nft_set_elem_change_active(set, &rbe->ext);
167 return rbe;
168 }
169 }
170 return NULL;
171 }
172
nft_rbtree_walk(const struct nft_ctx * ctx,const struct nft_set * set,struct nft_set_iter * iter)173 static void nft_rbtree_walk(const struct nft_ctx *ctx,
174 const struct nft_set *set,
175 struct nft_set_iter *iter)
176 {
177 const struct nft_rbtree *priv = nft_set_priv(set);
178 struct nft_rbtree_elem *rbe;
179 struct nft_set_elem elem;
180 struct rb_node *node;
181 u8 genmask = nft_genmask_cur(read_pnet(&set->pnet));
182
183 spin_lock_bh(&nft_rbtree_lock);
184 for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
185 rbe = rb_entry(node, struct nft_rbtree_elem, node);
186
187 if (iter->count < iter->skip)
188 goto cont;
189 if (!nft_set_elem_active(&rbe->ext, genmask))
190 goto cont;
191
192 elem.priv = rbe;
193
194 iter->err = iter->fn(ctx, set, iter, &elem);
195 if (iter->err < 0) {
196 spin_unlock_bh(&nft_rbtree_lock);
197 return;
198 }
199 cont:
200 iter->count++;
201 }
202 spin_unlock_bh(&nft_rbtree_lock);
203 }
204
nft_rbtree_privsize(const struct nlattr * const nla[])205 static unsigned int nft_rbtree_privsize(const struct nlattr * const nla[])
206 {
207 return sizeof(struct nft_rbtree);
208 }
209
nft_rbtree_init(const struct nft_set * set,const struct nft_set_desc * desc,const struct nlattr * const nla[])210 static int nft_rbtree_init(const struct nft_set *set,
211 const struct nft_set_desc *desc,
212 const struct nlattr * const nla[])
213 {
214 struct nft_rbtree *priv = nft_set_priv(set);
215
216 priv->root = RB_ROOT;
217 return 0;
218 }
219
nft_rbtree_destroy(const struct nft_set * set)220 static void nft_rbtree_destroy(const struct nft_set *set)
221 {
222 struct nft_rbtree *priv = nft_set_priv(set);
223 struct nft_rbtree_elem *rbe;
224 struct rb_node *node;
225
226 while ((node = priv->root.rb_node) != NULL) {
227 rb_erase(node, &priv->root);
228 rbe = rb_entry(node, struct nft_rbtree_elem, node);
229 nft_set_elem_destroy(set, rbe);
230 }
231 }
232
nft_rbtree_estimate(const struct nft_set_desc * desc,u32 features,struct nft_set_estimate * est)233 static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
234 struct nft_set_estimate *est)
235 {
236 unsigned int nsize;
237
238 nsize = sizeof(struct nft_rbtree_elem);
239 if (desc->size)
240 est->size = sizeof(struct nft_rbtree) + desc->size * nsize;
241 else
242 est->size = nsize;
243
244 est->class = NFT_SET_CLASS_O_LOG_N;
245
246 return true;
247 }
248
249 static struct nft_set_ops nft_rbtree_ops __read_mostly = {
250 .privsize = nft_rbtree_privsize,
251 .elemsize = offsetof(struct nft_rbtree_elem, ext),
252 .estimate = nft_rbtree_estimate,
253 .init = nft_rbtree_init,
254 .destroy = nft_rbtree_destroy,
255 .insert = nft_rbtree_insert,
256 .remove = nft_rbtree_remove,
257 .deactivate = nft_rbtree_deactivate,
258 .activate = nft_rbtree_activate,
259 .lookup = nft_rbtree_lookup,
260 .walk = nft_rbtree_walk,
261 .features = NFT_SET_INTERVAL | NFT_SET_MAP,
262 .owner = THIS_MODULE,
263 };
264
nft_rbtree_module_init(void)265 static int __init nft_rbtree_module_init(void)
266 {
267 return nft_register_set(&nft_rbtree_ops);
268 }
269
nft_rbtree_module_exit(void)270 static void __exit nft_rbtree_module_exit(void)
271 {
272 nft_unregister_set(&nft_rbtree_ops);
273 }
274
275 module_init(nft_rbtree_module_init);
276 module_exit(nft_rbtree_module_exit);
277
278 MODULE_LICENSE("GPL");
279 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
280 MODULE_ALIAS_NFT_SET();
281