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 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 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 * 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 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 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 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 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 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 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 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 282 acl_setioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 283 { 284 285 return EINVAL; 286 } 287 288 static int 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