1 /*- 2 * Copyright (c) 2004-2008 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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include <sys/cdefs.h> 27 __FBSDID("$FreeBSD$"); 28 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/mbuf.h> 46 #include <sys/module.h> 47 #include <sys/queue.h> 48 49 #include <sys/socket.h> 50 51 #include <net/if.h> 52 #include <net/if_media.h> 53 #include <net/ethernet.h> 54 #include <net/route.h> 55 56 #include <netproto/802_11/ieee80211_var.h> 57 58 enum { 59 ACL_POLICY_OPEN = 0, /* open, don't check ACL's */ 60 ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */ 61 ACL_POLICY_DENY = 2, /* deny traffic from MAC */ 62 /* 63 * NB: ACL_POLICY_RADIUS must be the same value as 64 * IEEE80211_MACCMD_POLICY_RADIUS because of the way 65 * acl_getpolicy() works. 66 */ 67 ACL_POLICY_RADIUS = 7, /* defer to RADIUS ACL server */ 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 acl_lock_t as_lock; 79 int as_policy; 80 uint32_t as_nacls; 81 TAILQ_HEAD(, acl) as_list; /* list of all ACL's */ 82 LIST_HEAD(, acl) as_hash[ACL_HASHSIZE]; 83 struct ieee80211vap *as_vap; 84 }; 85 86 /* simple hash is enough for variation of macaddr */ 87 #define ACL_HASH(addr) \ 88 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE) 89 90 static MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl"); 91 92 static int acl_free_all(struct ieee80211vap *); 93 94 /* number of references from net80211 layer */ 95 static int nrefs = 0; 96 97 static int 98 acl_attach(struct ieee80211vap *vap) 99 { 100 struct aclstate *as; 101 102 as = (struct aclstate *) kmalloc(sizeof(struct aclstate), 103 M_80211_ACL, M_INTWAIT | M_ZERO); 104 if (as == NULL) 105 return 0; 106 ACL_LOCK_INIT(as, "acl"); 107 TAILQ_INIT(&as->as_list); 108 as->as_policy = ACL_POLICY_OPEN; 109 as->as_vap = vap; 110 vap->iv_as = as; 111 nrefs++; /* NB: we assume caller locking */ 112 return 1; 113 } 114 115 static void 116 acl_detach(struct ieee80211vap *vap) 117 { 118 struct aclstate *as = vap->iv_as; 119 120 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 121 nrefs--; /* NB: we assume caller locking */ 122 123 acl_free_all(vap); 124 vap->iv_as = NULL; 125 ACL_LOCK_DESTROY(as); 126 kfree(as, M_80211_ACL); 127 } 128 129 static __inline struct acl * 130 _find_acl(struct aclstate *as, const uint8_t *macaddr) 131 { 132 struct acl *acl; 133 int hash; 134 135 hash = ACL_HASH(macaddr); 136 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 137 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr)) 138 return acl; 139 } 140 return NULL; 141 } 142 143 static void 144 _acl_free(struct aclstate *as, struct acl *acl) 145 { 146 ACL_LOCK_ASSERT(as); 147 148 TAILQ_REMOVE(&as->as_list, acl, acl_list); 149 LIST_REMOVE(acl, acl_hash); 150 kfree(acl, M_80211_ACL); 151 as->as_nacls--; 152 } 153 154 static int 155 acl_check(struct ieee80211vap *vap, const struct ieee80211_frame *wh) 156 { 157 struct aclstate *as = vap->iv_as; 158 159 switch (as->as_policy) { 160 case ACL_POLICY_OPEN: 161 case ACL_POLICY_RADIUS: 162 return 1; 163 case ACL_POLICY_ALLOW: 164 return _find_acl(as, wh->i_addr2) != NULL; 165 case ACL_POLICY_DENY: 166 return _find_acl(as, wh->i_addr2) == NULL; 167 } 168 return 0; /* should not happen */ 169 } 170 171 static int 172 acl_add(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 173 { 174 struct aclstate *as = vap->iv_as; 175 struct acl *acl, *new; 176 int hash; 177 178 new = (struct acl *) kmalloc(sizeof(struct acl), M_80211_ACL, M_INTWAIT | M_ZERO); 179 if (new == NULL) { 180 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 181 "ACL: add %s failed, no memory\n", ether_sprintf(mac)); 182 /* XXX statistic */ 183 return ENOMEM; 184 } 185 186 ACL_LOCK(as); 187 hash = ACL_HASH(mac); 188 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 189 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) { 190 ACL_UNLOCK(as); 191 kfree(new, M_80211_ACL); 192 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 193 "ACL: add %s failed, already present\n", 194 ether_sprintf(mac)); 195 return EEXIST; 196 } 197 } 198 IEEE80211_ADDR_COPY(new->acl_macaddr, mac); 199 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list); 200 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash); 201 as->as_nacls++; 202 ACL_UNLOCK(as); 203 204 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 205 "ACL: add %s\n", ether_sprintf(mac)); 206 return 0; 207 } 208 209 static int 210 acl_remove(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 211 { 212 struct aclstate *as = vap->iv_as; 213 struct acl *acl; 214 215 ACL_LOCK(as); 216 acl = _find_acl(as, mac); 217 if (acl != NULL) 218 _acl_free(as, acl); 219 ACL_UNLOCK(as); 220 221 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 222 "ACL: remove %s%s\n", ether_sprintf(mac), 223 acl == NULL ? ", not present" : ""); 224 225 return (acl == NULL ? ENOENT : 0); 226 } 227 228 static int 229 acl_free_all(struct ieee80211vap *vap) 230 { 231 struct aclstate *as = vap->iv_as; 232 struct acl *acl; 233 234 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, "ACL: %s\n", "free all"); 235 236 ACL_LOCK(as); 237 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL) 238 _acl_free(as, acl); 239 ACL_UNLOCK(as); 240 241 return 0; 242 } 243 244 static int 245 acl_setpolicy(struct ieee80211vap *vap, int policy) 246 { 247 struct aclstate *as = vap->iv_as; 248 249 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 250 "ACL: set policy to %u\n", policy); 251 252 switch (policy) { 253 case IEEE80211_MACCMD_POLICY_OPEN: 254 as->as_policy = ACL_POLICY_OPEN; 255 break; 256 case IEEE80211_MACCMD_POLICY_ALLOW: 257 as->as_policy = ACL_POLICY_ALLOW; 258 break; 259 case IEEE80211_MACCMD_POLICY_DENY: 260 as->as_policy = ACL_POLICY_DENY; 261 break; 262 case IEEE80211_MACCMD_POLICY_RADIUS: 263 as->as_policy = ACL_POLICY_RADIUS; 264 break; 265 default: 266 return EINVAL; 267 } 268 return 0; 269 } 270 271 static int 272 acl_getpolicy(struct ieee80211vap *vap) 273 { 274 struct aclstate *as = vap->iv_as; 275 276 return as->as_policy; 277 } 278 279 static int 280 acl_setioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 281 { 282 283 return EINVAL; 284 } 285 286 static int 287 acl_getioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 288 { 289 struct aclstate *as = vap->iv_as; 290 struct acl *acl; 291 struct ieee80211req_maclist *ap; 292 int error; 293 uint32_t i, space; 294 295 switch (ireq->i_val) { 296 case IEEE80211_MACCMD_POLICY: 297 ireq->i_val = as->as_policy; 298 return 0; 299 case IEEE80211_MACCMD_LIST: 300 space = as->as_nacls * IEEE80211_ADDR_LEN; 301 if (ireq->i_len == 0) { 302 ireq->i_len = space; /* return required space */ 303 return 0; /* NB: must not error */ 304 } 305 ap = (struct ieee80211req_maclist *) kmalloc(space, 306 M_TEMP, M_INTWAIT); 307 if (ap == NULL) 308 return ENOMEM; 309 i = 0; 310 ACL_LOCK(as); 311 TAILQ_FOREACH(acl, &as->as_list, acl_list) { 312 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr); 313 i++; 314 } 315 ACL_UNLOCK(as); 316 if (ireq->i_len >= space) { 317 error = copyout(ap, ireq->i_data, space); 318 ireq->i_len = space; 319 } else 320 error = copyout(ap, ireq->i_data, ireq->i_len); 321 kfree(ap, M_TEMP); 322 return error; 323 } 324 return EINVAL; 325 } 326 327 static const struct ieee80211_aclator mac = { 328 .iac_name = "mac", 329 .iac_attach = acl_attach, 330 .iac_detach = acl_detach, 331 .iac_check = acl_check, 332 .iac_add = acl_add, 333 .iac_remove = acl_remove, 334 .iac_flush = acl_free_all, 335 .iac_setpolicy = acl_setpolicy, 336 .iac_getpolicy = acl_getpolicy, 337 .iac_setioctl = acl_setioctl, 338 .iac_getioctl = acl_getioctl, 339 }; 340 IEEE80211_ACL_MODULE(wlan_acl, mac, 1); 341