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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
52
53
54
55
56
57static LIST_HEAD(sel_netnode_list);
58static DEFINE_SPINLOCK(sel_netnode_lock);
59static struct sel_netnode_bkt sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
60
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69
70static unsigned int sel_netnode_hashfn_ipv4(__be32 addr)
71{
72
73
74 return (addr & (SEL_NETNODE_HASH_SIZE - 1));
75}
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85
86static unsigned int sel_netnode_hashfn_ipv6(const struct in6_addr *addr)
87{
88
89
90
91 return (addr->s6_addr32[3] & (SEL_NETNODE_HASH_SIZE - 1));
92}
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103
104static struct sel_netnode *sel_netnode_find(const void *addr, u16 family)
105{
106 unsigned int idx;
107 struct sel_netnode *node;
108
109 switch (family) {
110 case PF_INET:
111 idx = sel_netnode_hashfn_ipv4(*(__be32 *)addr);
112 break;
113 case PF_INET6:
114 idx = sel_netnode_hashfn_ipv6(addr);
115 break;
116 default:
117 BUG();
118 return NULL;
119 }
120
121 list_for_each_entry_rcu(node, &sel_netnode_hash[idx].list, list)
122 if (node->nsec.family == family)
123 switch (family) {
124 case PF_INET:
125 if (node->nsec.addr.ipv4 == *(__be32 *)addr)
126 return node;
127 break;
128 case PF_INET6:
129 if (ipv6_addr_equal(&node->nsec.addr.ipv6,
130 addr))
131 return node;
132 break;
133 }
134
135 return NULL;
136}
137
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143
144
145
146static void sel_netnode_insert(struct sel_netnode *node)
147{
148 unsigned int idx;
149
150 switch (node->nsec.family) {
151 case PF_INET:
152 idx = sel_netnode_hashfn_ipv4(node->nsec.addr.ipv4);
153 break;
154 case PF_INET6:
155 idx = sel_netnode_hashfn_ipv6(&node->nsec.addr.ipv6);
156 break;
157 default:
158 BUG();
159 return;
160 }
161
162
163
164 list_add_rcu(&node->list, &sel_netnode_hash[idx].list);
165 if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) {
166 struct sel_netnode *tail;
167 tail = list_entry(
168 rcu_dereference_protected(sel_netnode_hash[idx].list.prev,
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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188
189
190static int sel_netnode_sid_slow(void *addr, u16 family, u32 *sid)
191{
192 int ret = -ENOMEM;
193 struct sel_netnode *node;
194 struct sel_netnode *new = NULL;
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 new = kzalloc(sizeof(*new), GFP_ATOMIC);
204 if (new == NULL)
205 goto out;
206 switch (family) {
207 case PF_INET:
208 ret = security_node_sid(&selinux_state, PF_INET,
209 addr, sizeof(struct in_addr), sid);
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 new->nsec.addr.ipv6 = *(struct in6_addr *)addr;
216 break;
217 default:
218 BUG();
219 ret = -EINVAL;
220 }
221 if (ret != 0)
222 goto out;
223
224 new->nsec.family = family;
225 new->nsec.sid = *sid;
226 sel_netnode_insert(new);
227
228out:
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 kfree(new);
234 }
235 return ret;
236}
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251
252int sel_netnode_sid(void *addr, u16 family, u32 *sid)
253{
254 struct sel_netnode *node;
255
256 rcu_read_lock();
257 node = sel_netnode_find(addr, family);
258 if (node != NULL) {
259 *sid = node->nsec.sid;
260 rcu_read_unlock();
261 return 0;
262 }
263 rcu_read_unlock();
264
265 return sel_netnode_sid_slow(addr, family, sid);
266}
267
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273
274
275void sel_netnode_flush(void)
276{
277 unsigned int idx;
278 struct sel_netnode *node, *node_tmp;
279
280 spin_lock_bh(&sel_netnode_lock);
281 for (idx = 0; idx < SEL_NETNODE_HASH_SIZE; idx++) {
282 list_for_each_entry_safe(node, node_tmp,
283 &sel_netnode_hash[idx].list, list) {
284 list_del_rcu(&node->list);
285 kfree_rcu(node, rcu);
286 }
287 sel_netnode_hash[idx].size = 0;
288 }
289 spin_unlock_bh(&sel_netnode_lock);
290}
291
292static __init int sel_netnode_init(void)
293{
294 int iter;
295
296 if (!selinux_enabled)
297 return 0;
298
299 for (iter = 0; iter < SEL_NETNODE_HASH_SIZE; iter++) {
300 INIT_LIST_HEAD(&sel_netnode_hash[iter].list);
301 sel_netnode_hash[iter].size = 0;
302 }
303
304 return 0;
305}
306
307__initcall(sel_netnode_init);
308