Line data Source code
1 : /*
2 : * hostapd / AP table
3 : * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
4 : * Copyright (c) 2003-2004, Instant802 Networks, Inc.
5 : * Copyright (c) 2006, Devicescape Software, Inc.
6 : *
7 : * This software may be distributed under the terms of the BSD license.
8 : * See README for more details.
9 : */
10 :
11 : #include "utils/includes.h"
12 :
13 : #include "utils/common.h"
14 : #include "utils/eloop.h"
15 : #include "common/ieee802_11_defs.h"
16 : #include "common/ieee802_11_common.h"
17 : #include "hostapd.h"
18 : #include "ap_config.h"
19 : #include "ieee802_11.h"
20 : #include "sta_info.h"
21 : #include "beacon.h"
22 : #include "ap_list.h"
23 :
24 :
25 : /* AP list is a double linked list with head->prev pointing to the end of the
26 : * list and tail->next = NULL. Entries are moved to the head of the list
27 : * whenever a beacon has been received from the AP in question. The tail entry
28 : * in this link will thus be the least recently used entry. */
29 :
30 :
31 7480 : static int ap_list_beacon_olbc(struct hostapd_iface *iface, struct ap_info *ap)
32 : {
33 : int i;
34 :
35 14960 : if (iface->current_mode == NULL ||
36 14929 : iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G ||
37 7449 : iface->conf->channel != ap->channel)
38 51 : return 0;
39 :
40 7429 : if (ap->erp != -1 && (ap->erp & ERP_INFO_NON_ERP_PRESENT))
41 0 : return 1;
42 :
43 36049 : for (i = 0; i < WLAN_SUPP_RATES_MAX; i++) {
44 36048 : int rate = (ap->supported_rates[i] & 0x7f) * 5;
45 36048 : if (rate == 60 || rate == 90 || rate > 110)
46 7428 : return 0;
47 : }
48 :
49 1 : return 1;
50 : }
51 :
52 :
53 7486 : static struct ap_info * ap_get_ap(struct hostapd_iface *iface, const u8 *ap)
54 : {
55 : struct ap_info *s;
56 :
57 7486 : s = iface->ap_hash[STA_HASH(ap)];
58 14981 : while (s != NULL && os_memcmp(s->addr, ap, ETH_ALEN) != 0)
59 9 : s = s->hnext;
60 7486 : return s;
61 : }
62 :
63 :
64 270 : static void ap_ap_list_add(struct hostapd_iface *iface, struct ap_info *ap)
65 : {
66 270 : if (iface->ap_list) {
67 33 : ap->prev = iface->ap_list->prev;
68 33 : iface->ap_list->prev = ap;
69 : } else
70 237 : ap->prev = ap;
71 270 : ap->next = iface->ap_list;
72 270 : iface->ap_list = ap;
73 270 : }
74 :
75 :
76 270 : static void ap_ap_list_del(struct hostapd_iface *iface, struct ap_info *ap)
77 : {
78 270 : if (iface->ap_list == ap)
79 243 : iface->ap_list = ap->next;
80 : else
81 27 : ap->prev->next = ap->next;
82 :
83 270 : if (ap->next)
84 6 : ap->next->prev = ap->prev;
85 264 : else if (iface->ap_list)
86 27 : iface->ap_list->prev = ap->prev;
87 270 : }
88 :
89 :
90 265 : static void ap_ap_hash_add(struct hostapd_iface *iface, struct ap_info *ap)
91 : {
92 265 : ap->hnext = iface->ap_hash[STA_HASH(ap->addr)];
93 265 : iface->ap_hash[STA_HASH(ap->addr)] = ap;
94 265 : }
95 :
96 :
97 265 : static void ap_ap_hash_del(struct hostapd_iface *iface, struct ap_info *ap)
98 : {
99 : struct ap_info *s;
100 :
101 265 : s = iface->ap_hash[STA_HASH(ap->addr)];
102 265 : if (s == NULL) return;
103 265 : if (os_memcmp(s->addr, ap->addr, ETH_ALEN) == 0) {
104 262 : iface->ap_hash[STA_HASH(ap->addr)] = s->hnext;
105 262 : return;
106 : }
107 :
108 9 : while (s->hnext != NULL &&
109 3 : os_memcmp(s->hnext->addr, ap->addr, ETH_ALEN) != 0)
110 0 : s = s->hnext;
111 3 : if (s->hnext != NULL)
112 3 : s->hnext = s->hnext->hnext;
113 : else
114 0 : wpa_printf(MSG_INFO, "AP: could not remove AP " MACSTR
115 0 : " from hash table", MAC2STR(ap->addr));
116 : }
117 :
118 :
119 265 : static void ap_free_ap(struct hostapd_iface *iface, struct ap_info *ap)
120 : {
121 265 : ap_ap_hash_del(iface, ap);
122 265 : ap_ap_list_del(iface, ap);
123 :
124 265 : iface->num_ap--;
125 265 : os_free(ap);
126 265 : }
127 :
128 :
129 1395 : static void hostapd_free_aps(struct hostapd_iface *iface)
130 : {
131 : struct ap_info *ap, *prev;
132 :
133 1395 : ap = iface->ap_list;
134 :
135 3032 : while (ap) {
136 242 : prev = ap;
137 242 : ap = ap->next;
138 242 : ap_free_ap(iface, prev);
139 : }
140 :
141 1395 : iface->ap_list = NULL;
142 1395 : }
143 :
144 :
145 266 : static struct ap_info * ap_ap_add(struct hostapd_iface *iface, const u8 *addr)
146 : {
147 : struct ap_info *ap;
148 :
149 266 : ap = os_zalloc(sizeof(struct ap_info));
150 266 : if (ap == NULL)
151 1 : return NULL;
152 :
153 : /* initialize AP info data */
154 265 : os_memcpy(ap->addr, addr, ETH_ALEN);
155 265 : ap_ap_list_add(iface, ap);
156 265 : iface->num_ap++;
157 265 : ap_ap_hash_add(iface, ap);
158 :
159 265 : if (iface->num_ap > iface->conf->ap_table_max_size && ap != ap->prev) {
160 132 : wpa_printf(MSG_DEBUG, "Removing the least recently used AP "
161 132 : MACSTR " from AP table", MAC2STR(ap->prev->addr));
162 22 : ap_free_ap(iface, ap->prev);
163 : }
164 :
165 265 : return ap;
166 : }
167 :
168 :
169 7500 : void ap_list_process_beacon(struct hostapd_iface *iface,
170 : const struct ieee80211_mgmt *mgmt,
171 : struct ieee802_11_elems *elems,
172 : struct hostapd_frame_info *fi)
173 : {
174 : struct ap_info *ap;
175 7500 : int new_ap = 0;
176 7500 : int set_beacon = 0;
177 :
178 7500 : if (iface->conf->ap_table_max_size < 1)
179 14 : return;
180 :
181 7486 : ap = ap_get_ap(iface, mgmt->bssid);
182 7486 : if (!ap) {
183 266 : ap = ap_ap_add(iface, mgmt->bssid);
184 266 : if (!ap) {
185 1 : wpa_printf(MSG_INFO,
186 : "Failed to allocate AP information entry");
187 1 : return;
188 : }
189 265 : new_ap = 1;
190 : }
191 :
192 14970 : merge_byte_arrays(ap->supported_rates, WLAN_SUPP_RATES_MAX,
193 7485 : elems->supp_rates, elems->supp_rates_len,
194 7485 : elems->ext_supp_rates, elems->ext_supp_rates_len);
195 :
196 7485 : if (elems->erp_info && elems->erp_info_len == 1)
197 7453 : ap->erp = elems->erp_info[0];
198 : else
199 32 : ap->erp = -1;
200 :
201 7485 : if (elems->ds_params && elems->ds_params_len == 1)
202 7485 : ap->channel = elems->ds_params[0];
203 0 : else if (elems->ht_operation && elems->ht_operation_len >= 1)
204 0 : ap->channel = elems->ht_operation[0];
205 0 : else if (fi)
206 0 : ap->channel = fi->channel;
207 :
208 7485 : if (elems->ht_capabilities)
209 7477 : ap->ht_support = 1;
210 : else
211 8 : ap->ht_support = 0;
212 :
213 7485 : os_get_reltime(&ap->last_beacon);
214 :
215 7485 : if (!new_ap && ap != iface->ap_list) {
216 : /* move AP entry into the beginning of the list so that the
217 : * oldest entry is always in the end of the list */
218 5 : ap_ap_list_del(iface, ap);
219 5 : ap_ap_list_add(iface, ap);
220 : }
221 :
222 14965 : if (!iface->olbc &&
223 7480 : ap_list_beacon_olbc(iface, ap)) {
224 1 : iface->olbc = 1;
225 7 : wpa_printf(MSG_DEBUG, "OLBC AP detected: " MACSTR
226 : " (channel %d) - enable protection",
227 6 : MAC2STR(ap->addr), ap->channel);
228 1 : set_beacon++;
229 : }
230 :
231 : #ifdef CONFIG_IEEE80211N
232 7488 : if (!iface->olbc_ht && !ap->ht_support &&
233 6 : (ap->channel == 0 ||
234 4 : ap->channel == iface->conf->channel ||
235 2 : ap->channel == iface->conf->channel +
236 1 : iface->conf->secondary_channel * 4)) {
237 2 : iface->olbc_ht = 1;
238 2 : hostapd_ht_operation_update(iface);
239 14 : wpa_printf(MSG_DEBUG, "OLBC HT AP detected: " MACSTR
240 : " (channel %d) - enable protection",
241 12 : MAC2STR(ap->addr), ap->channel);
242 2 : set_beacon++;
243 : }
244 : #endif /* CONFIG_IEEE80211N */
245 :
246 7485 : if (set_beacon)
247 2 : ieee802_11_update_beacons(iface);
248 : }
249 :
250 :
251 986 : static void ap_list_timer(void *eloop_ctx, void *timeout_ctx)
252 : {
253 986 : struct hostapd_iface *iface = eloop_ctx;
254 : struct os_reltime now;
255 : struct ap_info *ap;
256 986 : int set_beacon = 0;
257 :
258 986 : eloop_register_timeout(10, 0, ap_list_timer, iface, NULL);
259 :
260 986 : if (!iface->ap_list)
261 1928 : return;
262 :
263 44 : os_get_reltime(&now);
264 :
265 89 : while (iface->ap_list) {
266 44 : ap = iface->ap_list->prev;
267 44 : if (!os_reltime_expired(&now, &ap->last_beacon,
268 44 : iface->conf->ap_table_expiration_time))
269 43 : break;
270 :
271 1 : ap_free_ap(iface, ap);
272 : }
273 :
274 44 : if (iface->olbc || iface->olbc_ht) {
275 1 : int olbc = 0;
276 1 : int olbc_ht = 0;
277 :
278 1 : ap = iface->ap_list;
279 2 : while (ap && (olbc == 0 || olbc_ht == 0)) {
280 0 : if (ap_list_beacon_olbc(iface, ap))
281 0 : olbc = 1;
282 0 : if (!ap->ht_support)
283 0 : olbc_ht = 1;
284 0 : ap = ap->next;
285 : }
286 1 : if (!olbc && iface->olbc) {
287 1 : wpa_printf(MSG_DEBUG, "OLBC not detected anymore");
288 1 : iface->olbc = 0;
289 1 : set_beacon++;
290 : }
291 : #ifdef CONFIG_IEEE80211N
292 1 : if (!olbc_ht && iface->olbc_ht) {
293 1 : wpa_printf(MSG_DEBUG, "OLBC HT not detected anymore");
294 1 : iface->olbc_ht = 0;
295 1 : hostapd_ht_operation_update(iface);
296 1 : set_beacon++;
297 : }
298 : #endif /* CONFIG_IEEE80211N */
299 : }
300 :
301 44 : if (set_beacon)
302 1 : ieee802_11_update_beacons(iface);
303 : }
304 :
305 :
306 1202 : int ap_list_init(struct hostapd_iface *iface)
307 : {
308 1202 : eloop_register_timeout(10, 0, ap_list_timer, iface, NULL);
309 1202 : return 0;
310 : }
311 :
312 :
313 1395 : void ap_list_deinit(struct hostapd_iface *iface)
314 : {
315 1395 : eloop_cancel_timeout(ap_list_timer, iface, NULL);
316 1395 : hostapd_free_aps(iface);
317 1395 : }
|
