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21#include <linux/types.h>
22#include <linux/rcupdate.h>
23#include <linux/list.h>
24#include <linux/slab.h>
25#include <linux/spinlock.h>
26#include <linux/in.h>
27#include <linux/in6.h>
28#include <linux/ip.h>
29#include <linux/ipv6.h>
30#include <net/ip.h>
31#include <net/ipv6.h>
32
33#include "netnode.h"
34#include "objsec.h"
35
36#define SEL_NETNODE_HASH_SIZE 256
37#define SEL_NETNODE_HASH_BKT_LIMIT 16
38
39struct sel_netnode_bkt {
40 unsigned int size;
41 struct list_head list;
42};
43
44struct sel_netnode {
45 struct netnode_security_struct nsec;
46
47 struct list_head list;
48 struct rcu_head rcu;
49};
50
51
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53
54
55
56
57static DEFINE_SPINLOCK(sel_netnode_lock);
58static struct sel_netnode_bkt sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
59
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68
69static unsigned int sel_netnode_hashfn_ipv4(__be32 addr)
70{
71
72
73 return (addr & (SEL_NETNODE_HASH_SIZE - 1));
74}
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84
85static unsigned int sel_netnode_hashfn_ipv6(const struct in6_addr *addr)
86{
87
88
89
90 return (addr->s6_addr32[3] & (SEL_NETNODE_HASH_SIZE - 1));
91}
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102
103static struct sel_netnode *sel_netnode_find(const void *addr, u16 family)
104{
105 unsigned int idx;
106 struct sel_netnode *node;
107
108 switch (family) {
109 case PF_INET:
110 idx = sel_netnode_hashfn_ipv4(*(const __be32 *)addr);
111 break;
112 case PF_INET6:
113 idx = sel_netnode_hashfn_ipv6(addr);
114 break;
115 default:
116 BUG();
117 return NULL;
118 }
119
120 list_for_each_entry_rcu(node, &sel_netnode_hash[idx].list, list)
121 if (node->nsec.family == family)
122 switch (family) {
123 case PF_INET:
124 if (node->nsec.addr.ipv4 == *(const __be32 *)addr)
125 return node;
126 break;
127 case PF_INET6:
128 if (ipv6_addr_equal(&node->nsec.addr.ipv6,
129 addr))
130 return node;
131 break;
132 }
133
134 return NULL;
135}
136
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143
144
145static void sel_netnode_insert(struct sel_netnode *node)
146{
147 unsigned int idx;
148
149 switch (node->nsec.family) {
150 case PF_INET:
151 idx = sel_netnode_hashfn_ipv4(node->nsec.addr.ipv4);
152 break;
153 case PF_INET6:
154 idx = sel_netnode_hashfn_ipv6(&node->nsec.addr.ipv6);
155 break;
156 default:
157 BUG();
158 return;
159 }
160
161
162
163 list_add_rcu(&node->list, &sel_netnode_hash[idx].list);
164 if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) {
165 struct sel_netnode *tail;
166 tail = list_entry(
167 rcu_dereference_protected(
168 list_tail_rcu(&sel_netnode_hash[idx].list),
169 lockdep_is_held(&sel_netnode_lock)),
170 struct sel_netnode, list);
171 list_del_rcu(&tail->list);
172 kfree_rcu(tail, rcu);
173 } else
174 sel_netnode_hash[idx].size++;
175}
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189
190static int sel_netnode_sid_slow(void *addr, u16 family, u32 *sid)
191{
192 int ret;
193 struct sel_netnode *node;
194 struct sel_netnode *new;
195
196 spin_lock_bh(&sel_netnode_lock);
197 node = sel_netnode_find(addr, family);
198 if (node != NULL) {
199 *sid = node->nsec.sid;
200 spin_unlock_bh(&sel_netnode_lock);
201 return 0;
202 }
203
204 new = kzalloc(sizeof(*new), GFP_ATOMIC);
205 switch (family) {
206 case PF_INET:
207 ret = security_node_sid(&selinux_state, PF_INET,
208 addr, sizeof(struct in_addr), sid);
209 if (new)
210 new->nsec.addr.ipv4 = *(__be32 *)addr;
211 break;
212 case PF_INET6:
213 ret = security_node_sid(&selinux_state, PF_INET6,
214 addr, sizeof(struct in6_addr), sid);
215 if (new)
216 new->nsec.addr.ipv6 = *(struct in6_addr *)addr;
217 break;
218 default:
219 BUG();
220 ret = -EINVAL;
221 }
222 if (ret == 0 && new) {
223 new->nsec.family = family;
224 new->nsec.sid = *sid;
225 sel_netnode_insert(new);
226 } else
227 kfree(new);
228
229 spin_unlock_bh(&sel_netnode_lock);
230 if (unlikely(ret))
231 pr_warn("SELinux: failure in %s(), unable to determine network node label\n",
232 __func__);
233 return ret;
234}
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249
250int sel_netnode_sid(void *addr, u16 family, u32 *sid)
251{
252 struct sel_netnode *node;
253
254 rcu_read_lock();
255 node = sel_netnode_find(addr, family);
256 if (node != NULL) {
257 *sid = node->nsec.sid;
258 rcu_read_unlock();
259 return 0;
260 }
261 rcu_read_unlock();
262
263 return sel_netnode_sid_slow(addr, family, sid);
264}
265
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271
272
273void sel_netnode_flush(void)
274{
275 unsigned int idx;
276 struct sel_netnode *node, *node_tmp;
277
278 spin_lock_bh(&sel_netnode_lock);
279 for (idx = 0; idx < SEL_NETNODE_HASH_SIZE; idx++) {
280 list_for_each_entry_safe(node, node_tmp,
281 &sel_netnode_hash[idx].list, list) {
282 list_del_rcu(&node->list);
283 kfree_rcu(node, rcu);
284 }
285 sel_netnode_hash[idx].size = 0;
286 }
287 spin_unlock_bh(&sel_netnode_lock);
288}
289
290static __init int sel_netnode_init(void)
291{
292 int iter;
293
294 if (!selinux_enabled_boot)
295 return 0;
296
297 for (iter = 0; iter < SEL_NETNODE_HASH_SIZE; iter++) {
298 INIT_LIST_HEAD(&sel_netnode_hash[iter].list);
299 sel_netnode_hash[iter].size = 0;
300 }
301
302 return 0;
303}
304
305__initcall(sel_netnode_init);
306