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 * $FreeBSD: src/sys/net80211/ieee80211_acl.c,v 1.3.2.1 2005/09/03 22:40:02 sam Exp $ 32 * $DragonFly: src/sys/netproto/802_11/wlan_acl/ieee80211_acl.c,v 1.3 2006/12/22 23:57:53 swildner Exp $ 33 */ 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 #include <sys/serialize.h> 53 54 #include <sys/socket.h> 55 56 #include <net/if.h> 57 #include <net/if_arp.h> 58 #include <net/if_media.h> 59 #include <net/ethernet.h> 60 #include <net/route.h> 61 62 #include <netproto/802_11/ieee80211_var.h> 63 64 enum { 65 ACL_POLICY_OPEN = 0, /* open, don't check ACL's */ 66 ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */ 67 ACL_POLICY_DENY = 2, /* deny traffic from MAC */ 68 }; 69 70 #define ACL_HASHSIZE 32 71 72 struct acl { 73 TAILQ_ENTRY(acl) acl_list; 74 LIST_ENTRY(acl) acl_hash; 75 uint8_t acl_macaddr[IEEE80211_ADDR_LEN]; 76 }; 77 struct aclstate { 78 #if 0 79 acl_lock_t as_lock; 80 #endif 81 int as_policy; 82 int as_nacls; 83 TAILQ_HEAD(, acl) as_list; /* list of all ACL's */ 84 LIST_HEAD(, acl) as_hash[ACL_HASHSIZE]; 85 struct ieee80211com *as_ic; 86 }; 87 88 /* simple hash is enough for variation of macaddr */ 89 #define ACL_HASH(addr) \ 90 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE) 91 92 MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl"); 93 94 static int acl_free_all(struct ieee80211com *); 95 96 static int 97 acl_attach(struct ieee80211com *ic) 98 { 99 struct aclstate *as; 100 101 as = kmalloc(sizeof(struct aclstate), M_80211_ACL, M_NOWAIT | M_ZERO); 102 if (as == NULL) 103 return 0; 104 TAILQ_INIT(&as->as_list); 105 as->as_policy = ACL_POLICY_OPEN; 106 as->as_ic = ic; 107 ic->ic_as = as; 108 return 1; 109 } 110 111 static void 112 acl_detach(struct ieee80211com *ic) 113 { 114 struct aclstate *as = ic->ic_as; 115 116 acl_free_all(ic); 117 ic->ic_as = NULL; 118 kfree(as, M_DEVBUF); 119 } 120 121 static __inline struct acl * 122 _find_acl(struct aclstate *as, const uint8_t *macaddr) 123 { 124 struct acl *acl; 125 int hash; 126 127 hash = ACL_HASH(macaddr); 128 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 129 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr)) 130 return acl; 131 } 132 return NULL; 133 } 134 135 static void 136 _acl_free(struct aclstate *as, struct acl *acl) 137 { 138 ASSERT_SERIALIZED(as->as_ic->ic_ifp->if_serializer); 139 140 TAILQ_REMOVE(&as->as_list, acl, acl_list); 141 LIST_REMOVE(acl, acl_hash); 142 kfree(acl, M_80211_ACL); 143 as->as_nacls--; 144 } 145 146 static int 147 acl_check(struct ieee80211com *ic, const uint8_t mac[IEEE80211_ADDR_LEN]) 148 { 149 struct aclstate *as = ic->ic_as; 150 151 switch (as->as_policy) { 152 case ACL_POLICY_OPEN: 153 return 1; 154 case ACL_POLICY_ALLOW: 155 return _find_acl(as, mac) != NULL; 156 case ACL_POLICY_DENY: 157 return _find_acl(as, mac) == NULL; 158 } 159 return 0; /* should not happen */ 160 } 161 162 static int 163 acl_add(struct ieee80211com *ic, const uint8_t mac[IEEE80211_ADDR_LEN]) 164 { 165 struct aclstate *as = ic->ic_as; 166 struct acl *acl, *new; 167 int hash; 168 169 ASSERT_SERIALIZED(ic->ic_ifp->if_serializer); 170 171 new = kmalloc(sizeof(struct acl), M_80211_ACL, M_NOWAIT | M_ZERO); 172 if (new == NULL) { 173 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, 174 "ACL: add %6D failed, no memory\n", mac, ":"); 175 /* XXX statistic */ 176 return ENOMEM; 177 } 178 179 hash = ACL_HASH(mac); 180 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 181 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) { 182 FREE(new, M_80211_ACL); 183 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, 184 "ACL: add %6D failed, already present\n", 185 mac, ":"); 186 return EEXIST; 187 } 188 } 189 IEEE80211_ADDR_COPY(new->acl_macaddr, mac); 190 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list); 191 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash); 192 as->as_nacls++; 193 194 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, 195 "ACL: add %6D\n", mac, ":"); 196 return 0; 197 } 198 199 static int 200 acl_remove(struct ieee80211com *ic, const uint8_t mac[IEEE80211_ADDR_LEN]) 201 { 202 struct aclstate *as = ic->ic_as; 203 struct acl *acl; 204 205 ASSERT_SERIALIZED(ic->ic_ifp->if_serializer); 206 207 acl = _find_acl(as, mac); 208 if (acl != NULL) 209 _acl_free(as, acl); 210 211 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, 212 "ACL: remove %6D%s\n", 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 ASSERT_SERIALIZED(ic->ic_ifp->if_serializer); 225 226 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, "ACL: %s\n", "free all"); 227 228 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL) 229 _acl_free(as, acl); 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 return ((struct aclstate *)(ic->ic_as))->as_policy; 262 } 263 264 static int 265 acl_setioctl(struct ieee80211com *ic, struct ieee80211req *ireq) 266 { 267 return EINVAL; 268 } 269 270 static int 271 acl_getioctl(struct ieee80211com *ic, struct ieee80211req *ireq) 272 { 273 struct aclstate *as = ic->ic_as; 274 struct acl *acl; 275 struct ieee80211req_maclist *ap; 276 int error, space, i; 277 278 ASSERT_SERIALIZED(ic->ic_ifp->if_serializer); 279 280 switch (ireq->i_val) { 281 case IEEE80211_MACCMD_POLICY: 282 ireq->i_val = as->as_policy; 283 return 0; 284 case IEEE80211_MACCMD_LIST: 285 space = as->as_nacls * IEEE80211_ADDR_LEN; 286 if (ireq->i_len == 0) { 287 ireq->i_len = space; /* return required space */ 288 return 0; /* NB: must not error */ 289 } 290 ap = kmalloc(space, M_TEMP, M_NOWAIT); 291 if (ap == NULL) 292 return ENOMEM; 293 i = 0; 294 TAILQ_FOREACH(acl, &as->as_list, acl_list) { 295 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr); 296 i++; 297 } 298 if (ireq->i_len >= space) { 299 error = copyout(ap, ireq->i_data, space); 300 ireq->i_len = space; 301 } else 302 error = copyout(ap, ireq->i_data, ireq->i_len); 303 kfree(ap, M_TEMP); 304 return error; 305 } 306 return EINVAL; 307 } 308 309 static const struct ieee80211_aclator mac = { 310 .iac_name = "mac", 311 .iac_attach = acl_attach, 312 .iac_detach = acl_detach, 313 .iac_check = acl_check, 314 .iac_add = acl_add, 315 .iac_remove = acl_remove, 316 .iac_flush = acl_free_all, 317 .iac_setpolicy = acl_setpolicy, 318 .iac_getpolicy = acl_getpolicy, 319 .iac_setioctl = acl_setioctl, 320 .iac_getioctl = acl_getioctl, 321 }; 322 323 /* 324 * Module glue. 325 */ 326 static int 327 wlan_acl_modevent(module_t mod, int type, void *unused) 328 { 329 switch (type) { 330 case MOD_LOAD: 331 if (bootverbose) 332 kprintf("wlan: <802.11 MAC ACL support>\n"); 333 ieee80211_aclator_register(&mac); 334 return 0; 335 case MOD_UNLOAD: 336 ieee80211_aclator_unregister(&mac); 337 return 0; 338 } 339 return EINVAL; 340 } 341 342 static moduledata_t wlan_acl_mod = { 343 "wlan_acl", 344 wlan_acl_modevent, 345 0 346 }; 347 DECLARE_MODULE(wlan_acl, wlan_acl_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST); 348 MODULE_VERSION(wlan_acl, 1); 349 MODULE_DEPEND(wlan_acl, wlan, 1, 1, 1); 350