1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2004-2008 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include <sys/cdefs.h>
29 /*
30 * IEEE 802.11 MAC ACL support.
31 *
32 * When this module is loaded the sender address of each auth mgt
33 * frame is passed to the iac_check method and the module indicates
34 * if the frame should be accepted or rejected. If the policy is
35 * set to ACL_POLICY_OPEN then all frames are accepted w/o checking
36 * the address. Otherwise, the address is looked up in the database
37 * and if found the frame is either accepted (ACL_POLICY_ALLOW)
38 * or rejected (ACL_POLICY_DENT).
39 */
40 #include "opt_wlan.h"
41
42 #include <sys/param.h>
43 #include <sys/kernel.h>
44 #include <sys/systm.h>
45 #include <sys/malloc.h>
46 #include <sys/mbuf.h>
47 #include <sys/module.h>
48 #include <sys/queue.h>
49
50 #include <sys/socket.h>
51
52 #include <net/if.h>
53 #include <net/if_media.h>
54 #include <net/ethernet.h>
55 #include <net/route.h>
56
57 #include <net80211/ieee80211_var.h>
58
59 enum {
60 ACL_POLICY_OPEN = 0, /* open, don't check ACL's */
61 ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */
62 ACL_POLICY_DENY = 2, /* deny traffic from MAC */
63 /*
64 * NB: ACL_POLICY_RADIUS must be the same value as
65 * IEEE80211_MACCMD_POLICY_RADIUS because of the way
66 * acl_getpolicy() works.
67 */
68 ACL_POLICY_RADIUS = 7, /* defer to RADIUS ACL server */
69 };
70
71 #define ACL_HASHSIZE 32
72
73 struct acl {
74 TAILQ_ENTRY(acl) acl_list;
75 LIST_ENTRY(acl) acl_hash;
76 uint8_t acl_macaddr[IEEE80211_ADDR_LEN];
77 };
78 struct aclstate {
79 acl_lock_t as_lock;
80 int as_policy;
81 uint32_t as_nacls;
82 TAILQ_HEAD(, acl) as_list; /* list of all ACL's */
83 LIST_HEAD(, acl) as_hash[ACL_HASHSIZE];
84 struct ieee80211vap *as_vap;
85 };
86
87 /* simple hash is enough for variation of macaddr */
88 #define ACL_HASH(addr) \
89 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE)
90
91 static MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl");
92
93 static int acl_free_all(struct ieee80211vap *);
94
95 /* number of references from net80211 layer */
96 static int nrefs = 0;
97
98 static int
acl_attach(struct ieee80211vap * vap)99 acl_attach(struct ieee80211vap *vap)
100 {
101 struct aclstate *as;
102
103 as = (struct aclstate *) IEEE80211_MALLOC(sizeof(struct aclstate),
104 M_80211_ACL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
105 if (as == NULL)
106 return 0;
107 ACL_LOCK_INIT(as, "acl");
108 TAILQ_INIT(&as->as_list);
109 as->as_policy = ACL_POLICY_OPEN;
110 as->as_vap = vap;
111 vap->iv_as = as;
112 nrefs++; /* NB: we assume caller locking */
113 return 1;
114 }
115
116 static void
acl_detach(struct ieee80211vap * vap)117 acl_detach(struct ieee80211vap *vap)
118 {
119 struct aclstate *as = vap->iv_as;
120
121 KASSERT(nrefs > 0, ("imbalanced attach/detach"));
122 nrefs--; /* NB: we assume caller locking */
123
124 acl_free_all(vap);
125 vap->iv_as = NULL;
126 ACL_LOCK_DESTROY(as);
127 IEEE80211_FREE(as, M_80211_ACL);
128 }
129
130 static __inline struct acl *
_find_acl(struct aclstate * as,const uint8_t * macaddr)131 _find_acl(struct aclstate *as, const uint8_t *macaddr)
132 {
133 struct acl *acl;
134 int hash;
135
136 hash = ACL_HASH(macaddr);
137 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
138 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr))
139 return acl;
140 }
141 return NULL;
142 }
143
144 static void
_acl_free(struct aclstate * as,struct acl * acl)145 _acl_free(struct aclstate *as, struct acl *acl)
146 {
147 ACL_LOCK_ASSERT(as);
148
149 TAILQ_REMOVE(&as->as_list, acl, acl_list);
150 LIST_REMOVE(acl, acl_hash);
151 IEEE80211_FREE(acl, M_80211_ACL);
152 as->as_nacls--;
153 }
154
155 static int
acl_check(struct ieee80211vap * vap,const struct ieee80211_frame * wh)156 acl_check(struct ieee80211vap *vap, const struct ieee80211_frame *wh)
157 {
158 struct aclstate *as = vap->iv_as;
159
160 switch (as->as_policy) {
161 case ACL_POLICY_OPEN:
162 case ACL_POLICY_RADIUS:
163 return 1;
164 case ACL_POLICY_ALLOW:
165 return _find_acl(as, wh->i_addr2) != NULL;
166 case ACL_POLICY_DENY:
167 return _find_acl(as, wh->i_addr2) == NULL;
168 }
169 return 0; /* should not happen */
170 }
171
172 static int
acl_add(struct ieee80211vap * vap,const uint8_t mac[IEEE80211_ADDR_LEN])173 acl_add(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN])
174 {
175 struct aclstate *as = vap->iv_as;
176 struct acl *acl, *new;
177 int hash;
178
179 new = (struct acl *) IEEE80211_MALLOC(sizeof(struct acl),
180 M_80211_ACL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
181 if (new == NULL) {
182 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL,
183 "ACL: add %s failed, no memory\n", ether_sprintf(mac));
184 /* XXX statistic */
185 return ENOMEM;
186 }
187
188 ACL_LOCK(as);
189 hash = ACL_HASH(mac);
190 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
191 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) {
192 ACL_UNLOCK(as);
193 IEEE80211_FREE(new, M_80211_ACL);
194 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL,
195 "ACL: add %s failed, already present\n",
196 ether_sprintf(mac));
197 return EEXIST;
198 }
199 }
200 IEEE80211_ADDR_COPY(new->acl_macaddr, mac);
201 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list);
202 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash);
203 as->as_nacls++;
204 ACL_UNLOCK(as);
205
206 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL,
207 "ACL: add %s\n", ether_sprintf(mac));
208 return 0;
209 }
210
211 static int
acl_remove(struct ieee80211vap * vap,const uint8_t mac[IEEE80211_ADDR_LEN])212 acl_remove(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN])
213 {
214 struct aclstate *as = vap->iv_as;
215 struct acl *acl;
216
217 ACL_LOCK(as);
218 acl = _find_acl(as, mac);
219 if (acl != NULL)
220 _acl_free(as, acl);
221 ACL_UNLOCK(as);
222
223 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL,
224 "ACL: remove %s%s\n", ether_sprintf(mac),
225 acl == NULL ? ", not present" : "");
226
227 return (acl == NULL ? ENOENT : 0);
228 }
229
230 static int
acl_free_all(struct ieee80211vap * vap)231 acl_free_all(struct ieee80211vap *vap)
232 {
233 struct aclstate *as = vap->iv_as;
234 struct acl *acl;
235
236 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, "ACL: %s\n", "free all");
237
238 ACL_LOCK(as);
239 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL)
240 _acl_free(as, acl);
241 ACL_UNLOCK(as);
242
243 return 0;
244 }
245
246 static int
acl_setpolicy(struct ieee80211vap * vap,int policy)247 acl_setpolicy(struct ieee80211vap *vap, int policy)
248 {
249 struct aclstate *as = vap->iv_as;
250
251 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL,
252 "ACL: set policy to %u\n", policy);
253
254 switch (policy) {
255 case IEEE80211_MACCMD_POLICY_OPEN:
256 as->as_policy = ACL_POLICY_OPEN;
257 break;
258 case IEEE80211_MACCMD_POLICY_ALLOW:
259 as->as_policy = ACL_POLICY_ALLOW;
260 break;
261 case IEEE80211_MACCMD_POLICY_DENY:
262 as->as_policy = ACL_POLICY_DENY;
263 break;
264 case IEEE80211_MACCMD_POLICY_RADIUS:
265 as->as_policy = ACL_POLICY_RADIUS;
266 break;
267 default:
268 return EINVAL;
269 }
270 return 0;
271 }
272
273 static int
acl_getpolicy(struct ieee80211vap * vap)274 acl_getpolicy(struct ieee80211vap *vap)
275 {
276 struct aclstate *as = vap->iv_as;
277
278 return as->as_policy;
279 }
280
281 static int
acl_setioctl(struct ieee80211vap * vap,struct ieee80211req * ireq)282 acl_setioctl(struct ieee80211vap *vap, struct ieee80211req *ireq)
283 {
284
285 return EINVAL;
286 }
287
288 static int
acl_getioctl(struct ieee80211vap * vap,struct ieee80211req * ireq)289 acl_getioctl(struct ieee80211vap *vap, struct ieee80211req *ireq)
290 {
291 struct aclstate *as = vap->iv_as;
292 struct acl *acl;
293 struct ieee80211req_maclist *ap;
294 int error;
295 uint32_t i, space;
296
297 switch (ireq->i_val) {
298 case IEEE80211_MACCMD_POLICY:
299 ireq->i_val = as->as_policy;
300 return 0;
301 case IEEE80211_MACCMD_LIST:
302 space = as->as_nacls * IEEE80211_ADDR_LEN;
303 if (ireq->i_len == 0) {
304 ireq->i_len = space; /* return required space */
305 return 0; /* NB: must not error */
306 }
307 ap = (struct ieee80211req_maclist *) IEEE80211_MALLOC(space,
308 M_TEMP, IEEE80211_M_NOWAIT);
309 if (ap == NULL)
310 return ENOMEM;
311 i = 0;
312 ACL_LOCK(as);
313 TAILQ_FOREACH(acl, &as->as_list, acl_list) {
314 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr);
315 i++;
316 }
317 ACL_UNLOCK(as);
318 if (ireq->i_len >= space) {
319 error = copyout(ap, ireq->i_data, space);
320 ireq->i_len = space;
321 } else
322 error = copyout(ap, ireq->i_data, ireq->i_len);
323 IEEE80211_FREE(ap, M_TEMP);
324 return error;
325 }
326 return EINVAL;
327 }
328
329 static const struct ieee80211_aclator mac = {
330 .iac_name = "mac",
331 .iac_attach = acl_attach,
332 .iac_detach = acl_detach,
333 .iac_check = acl_check,
334 .iac_add = acl_add,
335 .iac_remove = acl_remove,
336 .iac_flush = acl_free_all,
337 .iac_setpolicy = acl_setpolicy,
338 .iac_getpolicy = acl_getpolicy,
339 .iac_setioctl = acl_setioctl,
340 .iac_getioctl = acl_getioctl,
341 };
342 IEEE80211_ACL_MODULE(wlan_acl, mac, 1);
343