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 * $FreeBSD: head/sys/net80211/ieee80211_acl.c 186302 2008-12-18 23:00:09Z sam $ 26 */ 27 28 /* 29 * IEEE 802.11 MAC ACL support. 30 * 31 * When this module is loaded the sender address of each auth mgt 32 * frame is passed to the iac_check method and the module indicates 33 * if the frame should be accepted or rejected. If the policy is 34 * set to ACL_POLICY_OPEN then all frames are accepted w/o checking 35 * the address. Otherwise, the address is looked up in the database 36 * and if found the frame is either accepted (ACL_POLICY_ALLOW) 37 * or rejected (ACL_POLICY_DENT). 38 */ 39 #include "opt_wlan.h" 40 41 #include <sys/param.h> 42 #include <sys/kernel.h> 43 #include <sys/systm.h> 44 #include <sys/mbuf.h> 45 #include <sys/module.h> 46 #include <sys/queue.h> 47 48 #include <sys/socket.h> 49 50 #include <net/if.h> 51 #include <net/if_media.h> 52 #include <net/ethernet.h> 53 #include <net/route.h> 54 55 #include <netproto/802_11/ieee80211_var.h> 56 57 enum { 58 ACL_POLICY_OPEN = 0, /* open, don't check ACL's */ 59 ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */ 60 ACL_POLICY_DENY = 2, /* deny traffic from MAC */ 61 /* 62 * NB: ACL_POLICY_RADIUS must be the same value as 63 * IEEE80211_MACCMD_POLICY_RADIUS because of the way 64 * acl_getpolicy() works. 65 */ 66 ACL_POLICY_RADIUS = 7, /* defer to RADIUS ACL server */ 67 }; 68 69 #define ACL_HASHSIZE 32 70 71 struct acl { 72 TAILQ_ENTRY(acl) acl_list; 73 LIST_ENTRY(acl) acl_hash; 74 uint8_t acl_macaddr[IEEE80211_ADDR_LEN]; 75 }; 76 struct aclstate { 77 int as_policy; 78 int as_nacls; 79 TAILQ_HEAD(, acl) as_list; /* list of all ACL's */ 80 LIST_HEAD(, acl) as_hash[ACL_HASHSIZE]; 81 struct ieee80211vap *as_vap; 82 }; 83 84 /* simple hash is enough for variation of macaddr */ 85 #define ACL_HASH(addr) \ 86 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE) 87 88 MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl"); 89 90 static int acl_free_all(struct ieee80211vap *); 91 92 /* number of references from net80211 layer */ 93 static int nrefs = 0; 94 95 static int 96 acl_attach(struct ieee80211vap *vap) 97 { 98 struct aclstate *as; 99 100 as = (struct aclstate *) kmalloc(sizeof(struct aclstate), 101 M_80211_ACL, M_INTWAIT | 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_vap = vap; 107 vap->iv_as = as; 108 nrefs++; /* NB: we assume caller locking */ 109 return 1; 110 } 111 112 static void 113 acl_detach(struct ieee80211vap *vap) 114 { 115 struct aclstate *as = vap->iv_as; 116 117 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 118 nrefs--; /* NB: we assume caller locking */ 119 120 acl_free_all(vap); 121 vap->iv_as = NULL; 122 kfree(as, M_80211_ACL); 123 } 124 125 static __inline struct acl * 126 _find_acl(struct aclstate *as, const uint8_t *macaddr) 127 { 128 struct acl *acl; 129 int hash; 130 131 hash = ACL_HASH(macaddr); 132 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 133 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr)) 134 return acl; 135 } 136 return NULL; 137 } 138 139 static void 140 _acl_free(struct aclstate *as, struct acl *acl) 141 { 142 143 TAILQ_REMOVE(&as->as_list, acl, acl_list); 144 LIST_REMOVE(acl, acl_hash); 145 kfree(acl, M_80211_ACL); 146 as->as_nacls--; 147 } 148 149 static int 150 acl_check(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 151 { 152 struct aclstate *as = vap->iv_as; 153 154 switch (as->as_policy) { 155 case ACL_POLICY_OPEN: 156 case ACL_POLICY_RADIUS: 157 return 1; 158 case ACL_POLICY_ALLOW: 159 return _find_acl(as, mac) != NULL; 160 case ACL_POLICY_DENY: 161 return _find_acl(as, mac) == NULL; 162 } 163 return 0; /* should not happen */ 164 } 165 166 static int 167 acl_add(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 168 { 169 struct aclstate *as = vap->iv_as; 170 struct acl *acl, *new; 171 #ifdef IEEE80211_DEBUG 172 char ethstr[ETHER_ADDRSTRLEN + 1]; 173 #endif 174 int hash; 175 176 new = (struct acl *) kmalloc(sizeof(struct acl), M_80211_ACL, M_INTWAIT | M_ZERO); 177 if (new == NULL) { 178 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 179 "ACL: add %s failed, no memory\n", kether_ntoa(mac, ethstr)); 180 /* XXX statistic */ 181 return ENOMEM; 182 } 183 184 hash = ACL_HASH(mac); 185 LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) { 186 if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) { 187 kfree(new, M_80211_ACL); 188 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 189 "ACL: add %s failed, already present\n", 190 kether_ntoa(mac, ethstr)); 191 return EEXIST; 192 } 193 } 194 IEEE80211_ADDR_COPY(new->acl_macaddr, mac); 195 TAILQ_INSERT_TAIL(&as->as_list, new, acl_list); 196 LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash); 197 as->as_nacls++; 198 199 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 200 "ACL: add %s\n", kether_ntoa(mac, ethstr)); 201 return 0; 202 } 203 204 static int 205 acl_remove(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN]) 206 { 207 struct aclstate *as = vap->iv_as; 208 struct acl *acl; 209 #ifdef IEEE80211_DEBUG 210 char ethstr[ETHER_ADDRSTRLEN + 1]; 211 #endif 212 213 acl = _find_acl(as, mac); 214 if (acl != NULL) 215 _acl_free(as, acl); 216 217 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 218 "ACL: remove %s%s\n", kether_ntoa(mac, ethstr), 219 acl == NULL ? ", not present" : ""); 220 221 return (acl == NULL ? ENOENT : 0); 222 } 223 224 static int 225 acl_free_all(struct ieee80211vap *vap) 226 { 227 struct aclstate *as = vap->iv_as; 228 struct acl *acl; 229 230 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, "ACL: %s\n", "free all"); 231 232 while ((acl = TAILQ_FIRST(&as->as_list)) != NULL) 233 _acl_free(as, acl); 234 235 return 0; 236 } 237 238 static int 239 acl_setpolicy(struct ieee80211vap *vap, int policy) 240 { 241 struct aclstate *as = vap->iv_as; 242 243 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ACL, 244 "ACL: set policy to %u\n", policy); 245 246 switch (policy) { 247 case IEEE80211_MACCMD_POLICY_OPEN: 248 as->as_policy = ACL_POLICY_OPEN; 249 break; 250 case IEEE80211_MACCMD_POLICY_ALLOW: 251 as->as_policy = ACL_POLICY_ALLOW; 252 break; 253 case IEEE80211_MACCMD_POLICY_DENY: 254 as->as_policy = ACL_POLICY_DENY; 255 break; 256 case IEEE80211_MACCMD_POLICY_RADIUS: 257 as->as_policy = ACL_POLICY_RADIUS; 258 break; 259 default: 260 return EINVAL; 261 } 262 return 0; 263 } 264 265 static int 266 acl_getpolicy(struct ieee80211vap *vap) 267 { 268 struct aclstate *as = vap->iv_as; 269 270 return as->as_policy; 271 } 272 273 static int 274 acl_setioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 275 { 276 277 return EINVAL; 278 } 279 280 static int 281 acl_getioctl(struct ieee80211vap *vap, struct ieee80211req *ireq) 282 { 283 struct aclstate *as = vap->iv_as; 284 struct acl *acl; 285 struct ieee80211req_maclist *ap; 286 int error, space, i; 287 288 switch (ireq->i_val) { 289 case IEEE80211_MACCMD_POLICY: 290 ireq->i_val = as->as_policy; 291 return 0; 292 case IEEE80211_MACCMD_LIST: 293 space = as->as_nacls * IEEE80211_ADDR_LEN; 294 if (ireq->i_len == 0) { 295 ireq->i_len = space; /* return required space */ 296 return 0; /* NB: must not error */ 297 } 298 ap = (struct ieee80211req_maclist *) kmalloc(space, 299 M_TEMP, M_INTWAIT); 300 if (ap == NULL) 301 return ENOMEM; 302 i = 0; 303 TAILQ_FOREACH(acl, &as->as_list, acl_list) { 304 IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr); 305 i++; 306 } 307 if (ireq->i_len >= space) { 308 error = copyout(ap, ireq->i_data, space); 309 ireq->i_len = space; 310 } else 311 error = copyout(ap, ireq->i_data, ireq->i_len); 312 kfree(ap, M_TEMP); 313 return error; 314 } 315 return EINVAL; 316 } 317 318 static const struct ieee80211_aclator mac = { 319 .iac_name = "mac", 320 .iac_attach = acl_attach, 321 .iac_detach = acl_detach, 322 .iac_check = acl_check, 323 .iac_add = acl_add, 324 .iac_remove = acl_remove, 325 .iac_flush = acl_free_all, 326 .iac_setpolicy = acl_setpolicy, 327 .iac_getpolicy = acl_getpolicy, 328 .iac_setioctl = acl_setioctl, 329 .iac_getioctl = acl_getioctl, 330 }; 331 IEEE80211_ACL_MODULE(wlan_acl, mac, 1); 332