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 <net80211/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 *) IEEE80211_MALLOC(sizeof(struct aclstate), 103 M_80211_ACL, IEEE80211_M_NOWAIT | IEEE80211_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 IEEE80211_FREE(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 IEEE80211_FREE(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 *) IEEE80211_MALLOC(sizeof(struct acl), 179 M_80211_ACL, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 180 if (new == NULL) { 181 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 182 "ACL: add %s failed, no memory\n", ether_sprintf(mac)); 183 /* XXX statistic */ 184 return ENOMEM; 185 } 186 187 ACL_LOCK(as); 188 hash = ACL_HASH(mac); 189 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 190 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) { 191 ACL_UNLOCK(as); 192 IEEE80211_FREE(new, M_80211_ACL); 193 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 194 "ACL: add %s failed, already present\n", 195 ether_sprintf(mac)); 196 return EEXIST; 197 } 198 } 199 IEEE80211_ADDR_COPY(new->acl_macaddr, mac); 200 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list); 201 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash); 202 as->as_nacls++; 203 ACL_UNLOCK(as); 204 205 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 206 "ACL: add %s\n", ether_sprintf(mac)); 207 return 0; 208 } 209 210 static int 211 acl_remove(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 212 { 213 struct aclstate *as = vap->iv_as; 214 struct acl *acl; 215 216 ACL_LOCK(as); 217 acl = _find_acl(as, mac); 218 if (acl != NULL) 219 _acl_free(as, acl); 220 ACL_UNLOCK(as); 221 222 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 223 "ACL: remove %s%s\n", ether_sprintf(mac), 224 acl == NULL ? ", not present" : ""); 225 226 return (acl == NULL ? ENOENT : 0); 227 } 228 229 static int 230 acl_free_all(struct ieee80211vap *vap) 231 { 232 struct aclstate *as = vap->iv_as; 233 struct acl *acl; 234 235 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, "ACL: %s\n", "free all"); 236 237 ACL_LOCK(as); 238 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL) 239 _acl_free(as, acl); 240 ACL_UNLOCK(as); 241 242 return 0; 243 } 244 245 static int 246 acl_setpolicy(struct ieee80211vap *vap, int policy) 247 { 248 struct aclstate *as = vap->iv_as; 249 250 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 251 "ACL: set policy to %u\n", policy); 252 253 switch (policy) { 254 case IEEE80211_MACCMD_POLICY_OPEN: 255 as->as_policy = ACL_POLICY_OPEN; 256 break; 257 case IEEE80211_MACCMD_POLICY_ALLOW: 258 as->as_policy = ACL_POLICY_ALLOW; 259 break; 260 case IEEE80211_MACCMD_POLICY_DENY: 261 as->as_policy = ACL_POLICY_DENY; 262 break; 263 case IEEE80211_MACCMD_POLICY_RADIUS: 264 as->as_policy = ACL_POLICY_RADIUS; 265 break; 266 default: 267 return EINVAL; 268 } 269 return 0; 270 } 271 272 static int 273 acl_getpolicy(struct ieee80211vap *vap) 274 { 275 struct aclstate *as = vap->iv_as; 276 277 return as->as_policy; 278 } 279 280 static int 281 acl_setioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 282 { 283 284 return EINVAL; 285 } 286 287 static int 288 acl_getioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 289 { 290 struct aclstate *as = vap->iv_as; 291 struct acl *acl; 292 struct ieee80211req_maclist *ap; 293 int error; 294 uint32_t i, space; 295 296 switch (ireq->i_val) { 297 case IEEE80211_MACCMD_POLICY: 298 ireq->i_val = as->as_policy; 299 return 0; 300 case IEEE80211_MACCMD_LIST: 301 space = as->as_nacls * IEEE80211_ADDR_LEN; 302 if (ireq->i_len == 0) { 303 ireq->i_len = space; /* return required space */ 304 return 0; /* NB: must not error */ 305 } 306 ap = (struct ieee80211req_maclist *) IEEE80211_MALLOC(space, 307 M_TEMP, IEEE80211_M_NOWAIT); 308 if (ap == NULL) 309 return ENOMEM; 310 i = 0; 311 ACL_LOCK(as); 312 TAILQ_FOREACH(acl, &as->as_list, acl_list) { 313 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr); 314 i++; 315 } 316 ACL_UNLOCK(as); 317 if (ireq->i_len >= space) { 318 error = copyout(ap, ireq->i_data, space); 319 ireq->i_len = space; 320 } else 321 error = copyout(ap, ireq->i_data, ireq->i_len); 322 IEEE80211_FREE(ap, M_TEMP); 323 return error; 324 } 325 return EINVAL; 326 } 327 328 static const struct ieee80211_aclator mac = { 329 .iac_name = "mac", 330 .iac_attach = acl_attach, 331 .iac_detach = acl_detach, 332 .iac_check = acl_check, 333 .iac_add = acl_add, 334 .iac_remove = acl_remove, 335 .iac_flush = acl_free_all, 336 .iac_setpolicy = acl_setpolicy, 337 .iac_getpolicy = acl_getpolicy, 338 .iac_setioctl = acl_setioctl, 339 .iac_getioctl = acl_getioctl, 340 }; 341 IEEE80211_ACL_MODULE(wlan_acl, mac, 1); 342