1 /*-
2 * Copyright (c) 2004-2005 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * Alternatively, this software may be distributed under the terms of the
17 * GNU General Public License ("GPL") version 2 as published by the Free
18 * Software Foundation.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: releng/6.2/sys/net80211/ieee80211_acl.c 149772 2005-09-03 22:40:02Z sam $");
34
35 /*
36 * IEEE 802.11 MAC ACL support.
37 *
38 * When this module is loaded the sender address of each received
39 * frame is passed to the iac_check method and the module indicates
40 * if the frame should be accepted or rejected. If the policy is
41 * set to ACL_POLICY_OPEN then all frames are accepted w/o checking
42 * the address. Otherwise, the address is looked up in the database
43 * and if found the frame is either accepted (ACL_POLICY_ALLOW)
44 * or rejected (ACL_POLICY_DENT).
45 */
46 #include <sys/param.h>
47 #include <sys/kernel.h>
48 #include <sys/systm.h>
49 #include <sys/mbuf.h>
50 #include <sys/module.h>
51 #include <sys/queue.h>
52
53 #include <sys/socket.h>
54
55 #include <net/if.h>
56 #include <net/if_media.h>
57 #include <net/ethernet.h>
58 #include <net/route.h>
59
60 #include <net80211/ieee80211_var.h>
61
62 enum {
63 ACL_POLICY_OPEN = 0, /* open, don't check ACL's */
64 ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */
65 ACL_POLICY_DENY = 2, /* deny traffic from MAC */
66 };
67
68 #define ACL_HASHSIZE 32
69
70 struct acl {
71 TAILQ_ENTRY(acl) acl_list;
72 LIST_ENTRY(acl) acl_hash;
73 u_int8_t acl_macaddr[IEEE80211_ADDR_LEN];
74 };
75 struct aclstate {
76 acl_lock_t as_lock;
77 int as_policy;
78 int as_nacls;
79 TAILQ_HEAD(, acl) as_list; /* list of all ACL's */
80 LIST_HEAD(, acl) as_hash[ACL_HASHSIZE];
81 struct ieee80211com *as_ic;
82 };
83
84 /* simple hash is enough for variation of macaddr */
85 #define ACL_HASH(addr) \
86 (((const u_int8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE)
87
88 MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl");
89
90 static int acl_free_all(struct ieee80211com *);
91
92 static int
93 acl_attach(struct ieee80211com *ic)
94 {
95 struct aclstate *as;
96
97 MALLOC(as, struct aclstate *, sizeof(struct aclstate),
98 M_80211_ACL, M_NOWAIT | M_ZERO);
99 if (as == NULL)
100 return 0;
101 ACL_LOCK_INIT(as, "acl");
102 TAILQ_INIT(&as->as_list);
103 as->as_policy = ACL_POLICY_OPEN;
104 as->as_ic = ic;
105 ic->ic_as = as;
106 return 1;
107 }
108
109 static void
110 acl_detach(struct ieee80211com *ic)
111 {
112 struct aclstate *as = ic->ic_as;
113
114 acl_free_all(ic);
115 ic->ic_as = NULL;
116 ACL_LOCK_DESTROY(as);
117 FREE(as, M_DEVBUF);
118 }
119
120 static __inline struct acl *
121 _find_acl(struct aclstate *as, const u_int8_t *macaddr)
122 {
123 struct acl *acl;
124 int hash;
125
126 hash = ACL_HASH(macaddr);
127 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
128 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr))
129 return acl;
130 }
131 return NULL;
132 }
133
134 static void
135 _acl_free(struct aclstate *as, struct acl *acl)
136 {
137 ACL_LOCK_ASSERT(as);
138
139 TAILQ_REMOVE(&as->as_list, acl, acl_list);
140 LIST_REMOVE(acl, acl_hash);
141 FREE(acl, M_80211_ACL);
142 as->as_nacls--;
143 }
144
145 static int
146 acl_check(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
147 {
148 struct aclstate *as = ic->ic_as;
149
150 switch (as->as_policy) {
151 case ACL_POLICY_OPEN:
152 return 1;
153 case ACL_POLICY_ALLOW:
154 return _find_acl(as, mac) != NULL;
155 case ACL_POLICY_DENY:
156 return _find_acl(as, mac) == NULL;
157 }
158 return 0; /* should not happen */
159 }
160
161 static int
162 acl_add(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
163 {
164 struct aclstate *as = ic->ic_as;
165 struct acl *acl, *new;
166 int hash;
167
168 MALLOC(new, struct acl *, sizeof(struct acl), M_80211_ACL, M_NOWAIT | M_ZERO);
169 if (new == NULL) {
170 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
171 "ACL: add %s failed, no memory\n", ether_sprintf(mac));
172 /* XXX statistic */
173 return ENOMEM;
174 }
175
176 ACL_LOCK(as);
177 hash = ACL_HASH(mac);
178 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
179 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) {
180 ACL_UNLOCK(as);
181 FREE(new, M_80211_ACL);
182 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
183 "ACL: add %s failed, already present\n",
184 ether_sprintf(mac));
185 return EEXIST;
186 }
187 }
188 IEEE80211_ADDR_COPY(new->acl_macaddr, mac);
189 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list);
190 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash);
191 as->as_nacls++;
192 ACL_UNLOCK(as);
193
194 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
195 "ACL: add %s\n", ether_sprintf(mac));
196 return 0;
197 }
198
199 static int
200 acl_remove(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
201 {
202 struct aclstate *as = ic->ic_as;
203 struct acl *acl;
204
205 ACL_LOCK(as);
206 acl = _find_acl(as, mac);
207 if (acl != NULL)
208 _acl_free(as, acl);
209 ACL_UNLOCK(as);
210
211 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
212 "ACL: remove %s%s\n", ether_sprintf(mac),
213 acl == NULL ? ", not present" : "");
214
215 return (acl == NULL ? ENOENT : 0);
216 }
217
218 static int
219 acl_free_all(struct ieee80211com *ic)
220 {
221 struct aclstate *as = ic->ic_as;
222 struct acl *acl;
223
224 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, "ACL: %s\n", "free all");
225
226 ACL_LOCK(as);
227 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL)
228 _acl_free(as, acl);
229 ACL_UNLOCK(as);
230
231 return 0;
232 }
233
234 static int
235 acl_setpolicy(struct ieee80211com *ic, int policy)
236 {
237 struct aclstate *as = ic->ic_as;
238
239 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
240 "ACL: set policy to %u\n", policy);
241
242 switch (policy) {
243 case IEEE80211_MACCMD_POLICY_OPEN:
244 as->as_policy = ACL_POLICY_OPEN;
245 break;
246 case IEEE80211_MACCMD_POLICY_ALLOW:
247 as->as_policy = ACL_POLICY_ALLOW;
248 break;
249 case IEEE80211_MACCMD_POLICY_DENY:
250 as->as_policy = ACL_POLICY_DENY;
251 break;
252 default:
253 return EINVAL;
254 }
255 return 0;
256 }
257
258 static int
259 acl_getpolicy(struct ieee80211com *ic)
260 {
261 struct aclstate *as = ic->ic_as;
262
263 return as->as_policy;
264 }
265
266 static int
267 acl_setioctl(struct ieee80211com *ic, struct ieee80211req *ireq)
268 {
269
270 return EINVAL;
271 }
272
273 static int
274 acl_getioctl(struct ieee80211com *ic, struct ieee80211req *ireq)
275 {
276 struct aclstate *as = ic->ic_as;
277 struct acl *acl;
278 struct ieee80211req_maclist *ap;
279 int error, space, i;
280
281 switch (ireq->i_val) {
282 case IEEE80211_MACCMD_POLICY:
283 ireq->i_val = as->as_policy;
284 return 0;
285 case IEEE80211_MACCMD_LIST:
286 space = as->as_nacls * IEEE80211_ADDR_LEN;
287 if (ireq->i_len == 0) {
288 ireq->i_len = space; /* return required space */
289 return 0; /* NB: must not error */
290 }
291 MALLOC(ap, struct ieee80211req_maclist *, space,
292 M_TEMP, M_NOWAIT);
293 if (ap == NULL)
294 return ENOMEM;
295 i = 0;
296 ACL_LOCK(as);
297 TAILQ_FOREACH(acl, &as->as_list, acl_list) {
298 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr);
299 i++;
300 }
301 ACL_UNLOCK(as);
302 if (ireq->i_len >= space) {
303 error = copyout(ap, ireq->i_data, space);
304 ireq->i_len = space;
305 } else
306 error = copyout(ap, ireq->i_data, ireq->i_len);
307 FREE(ap, M_TEMP);
308 return error;
309 }
310 return EINVAL;
311 }
312
313 static const struct ieee80211_aclator mac = {
314 .iac_name = "mac",
315 .iac_attach = acl_attach,
316 .iac_detach = acl_detach,
317 .iac_check = acl_check,
318 .iac_add = acl_add,
319 .iac_remove = acl_remove,
320 .iac_flush = acl_free_all,
321 .iac_setpolicy = acl_setpolicy,
322 .iac_getpolicy = acl_getpolicy,
323 .iac_setioctl = acl_setioctl,
324 .iac_getioctl = acl_getioctl,
325 };
326
327 /*
328 * Module glue.
329 */
330 static int
331 wlan_acl_modevent(module_t mod, int type, void *unused)
332 {
333 switch (type) {
334 case MOD_LOAD:
335 if (bootverbose)
336 printf("wlan: <802.11 MAC ACL support>\n");
337 ieee80211_aclator_register(&mac);
338 return 0;
339 case MOD_UNLOAD:
340 ieee80211_aclator_unregister(&mac);
341 return 0;
342 }
343 return EINVAL;
344 }
345
346 static moduledata_t wlan_acl_mod = {
347 "wlan_acl",
348 wlan_acl_modevent,
349 0
350 };
351 DECLARE_MODULE(wlan_acl, wlan_acl_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
352 MODULE_VERSION(wlan_acl, 1);
353 MODULE_DEPEND(wlan_acl, wlan, 1, 1, 1);
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