2 * This file contains the softmac's association logic.
4 * Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
5 * Joseph Jezak <josejx@gentoo.org>
6 * Larry Finger <Larry.Finger@lwfinger.net>
7 * Danny van Dyk <kugelfang@gentoo.org>
8 * Michael Buesch <mbuesch@freenet.de>
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of version 2 of the GNU General Public License as
12 * published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 * The full GNU General Public License is included in this distribution in the
24 * file called COPYING.
27 #include "ieee80211softmac_priv.h"
32 * Before you can associate, you have to authenticate.
36 /* Sends out an association request to the desired AP */
38 ieee80211softmac_assoc(struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
42 /* Switch to correct channel for this network */
43 mac->set_channel(mac->dev, net->channel);
45 /* Send association request */
46 ieee80211softmac_send_mgt_frame(mac, net, IEEE80211_STYPE_ASSOC_REQ, 0);
48 dprintk(KERN_INFO PFX "sent association request!\n");
50 /* Change the state to associating */
51 spin_lock_irqsave(&mac->lock, flags);
52 mac->associnfo.associating = 1;
53 mac->associated = 0; /* just to make sure */
55 /* Set a timer for timeout */
56 /* FIXME: make timeout configurable */
57 if (likely(mac->running))
58 schedule_delayed_work(&mac->associnfo.timeout, 5 * HZ);
59 spin_unlock_irqrestore(&mac->lock, flags);
63 ieee80211softmac_assoc_timeout(void *d)
65 struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d;
68 spin_lock_irqsave(&mac->lock, flags);
69 /* we might race against ieee80211softmac_handle_assoc_response,
70 * so make sure only one of us does something */
71 if (!mac->associnfo.associating) {
72 spin_unlock_irqrestore(&mac->lock, flags);
75 mac->associnfo.associating = 0;
76 mac->associnfo.bssvalid = 0;
78 spin_unlock_irqrestore(&mac->lock, flags);
80 dprintk(KERN_INFO PFX "assoc request timed out!\n");
81 /* FIXME: we need to know the network here. that requires a bit of restructuring */
82 ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, NULL);
86 ieee80211softmac_disassoc(struct ieee80211softmac_device *mac)
90 spin_lock_irqsave(&mac->lock, flags);
91 if (mac->associnfo.associating)
92 cancel_delayed_work(&mac->associnfo.timeout);
94 netif_carrier_off(mac->dev);
97 mac->associnfo.bssvalid = 0;
98 mac->associnfo.associating = 0;
99 ieee80211softmac_init_txrates(mac);
100 ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_DISASSOCIATED, NULL);
101 spin_unlock_irqrestore(&mac->lock, flags);
104 /* Sends out a disassociation request to the desired AP */
106 ieee80211softmac_send_disassoc_req(struct ieee80211softmac_device *mac, u16 reason)
108 struct ieee80211softmac_network *found;
110 if (mac->associnfo.bssvalid && mac->associated) {
111 found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
113 ieee80211softmac_send_mgt_frame(mac, found, IEEE80211_STYPE_DISASSOC, reason);
116 ieee80211softmac_disassoc(mac);
120 we_support_all_basic_rates(struct ieee80211softmac_device *mac, u8 *from, u8 from_len)
125 for (idx = 0; idx < (from_len); idx++) {
127 if (!(rate & IEEE80211_BASIC_RATE_MASK))
129 rate &= ~IEEE80211_BASIC_RATE_MASK;
130 if (!ieee80211softmac_ratesinfo_rate_supported(&mac->ratesinfo, rate))
137 network_matches_request(struct ieee80211softmac_device *mac, struct ieee80211_network *net)
139 /* we cannot associate to networks whose name we don't know */
140 if (ieee80211_is_empty_essid(net->ssid, net->ssid_len))
142 /* do not associate to a network whose BSSBasicRateSet we cannot support */
143 if (!we_support_all_basic_rates(mac, net->rates, net->rates_len))
145 /* do we really need to check the ex rates? */
146 if (!we_support_all_basic_rates(mac, net->rates_ex, net->rates_ex_len))
149 /* assume that users know what they're doing ...
150 * (note we don't let them select a net we're incompatible with) */
151 if (mac->associnfo.bssfixed) {
152 return !memcmp(mac->associnfo.bssid, net->bssid, ETH_ALEN);
155 /* if 'ANY' network requested, take any that doesn't have privacy enabled */
156 if (mac->associnfo.req_essid.len == 0
157 && !(net->capability & WLAN_CAPABILITY_PRIVACY))
159 if (net->ssid_len != mac->associnfo.req_essid.len)
161 if (!memcmp(net->ssid, mac->associnfo.req_essid.data, mac->associnfo.req_essid.len))
167 ieee80211softmac_assoc_notify(struct net_device *dev, void *context)
169 struct ieee80211softmac_device *mac = ieee80211_priv(dev);
170 ieee80211softmac_assoc_work((void*)mac);
173 /* This function is called to handle userspace requests (asynchronously) */
175 ieee80211softmac_assoc_work(void *d)
177 struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d;
178 struct ieee80211softmac_network *found = NULL;
179 struct ieee80211_network *net = NULL, *best = NULL;
183 /* ieee80211_disassoc might clear this */
184 bssvalid = mac->associnfo.bssvalid;
188 ieee80211softmac_send_disassoc_req(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT);
190 /* try to find the requested network in our list, if we found one already */
191 if (bssvalid || mac->associnfo.bssfixed)
192 found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
194 /* Search the ieee80211 networks for this network if we didn't find it by bssid,
195 * but only if we've scanned at least once (to get a better list of networks to
196 * select from). If we have not scanned before, the !found logic below will be
197 * invoked and will scan. */
198 if (!found && (mac->associnfo.scan_retry < IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT))
200 s8 rssi = -128; /* if I don't initialise, gcc emits an invalid warning
201 because it cannot follow the best pointer logic. */
202 spin_lock_irqsave(&mac->ieee->lock, flags);
203 list_for_each_entry(net, &mac->ieee->network_list, list) {
204 /* we're supposed to find the network with
205 * the best signal here, as we're asked to join
206 * any network with a specific ESSID, and many
207 * different ones could have that.
209 * I'll for now just go with the reported rssi.
211 * We also should take into account the rateset
212 * here to find the best BSSID to try.
214 if (network_matches_request(mac, net)) {
217 rssi = best->stats.rssi;
220 /* we already had a matching network, so
221 * compare their properties to get the
222 * better of the two ... (see above)
224 if (rssi < net->stats.rssi) {
226 rssi = best->stats.rssi;
230 /* if we unlock here, we might get interrupted and the `best'
231 * pointer could go stale */
233 found = ieee80211softmac_create_network(mac, best);
234 /* if found is still NULL, then we got -ENOMEM somewhere */
236 ieee80211softmac_add_network(mac, found);
238 spin_unlock_irqrestore(&mac->ieee->lock, flags);
242 if (mac->associnfo.scan_retry > 0) {
243 spin_lock_irqsave(&mac->lock, flags);
244 mac->associnfo.scan_retry--;
245 spin_unlock_irqrestore(&mac->lock, flags);
247 /* We know of no such network. Let's scan.
248 * NB: this also happens if we had no memory to copy the network info...
249 * Maybe we can hope to have more memory after scanning finishes ;)
251 dprintk(KERN_INFO PFX "Associate: Scanning for networks first.\n");
252 ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify, NULL);
253 if (ieee80211softmac_start_scan(mac))
254 dprintk(KERN_INFO PFX "Associate: failed to initiate scan. Is device up?\n");
257 spin_lock_irqsave(&mac->lock, flags);
258 mac->associnfo.associating = 0;
260 spin_unlock_irqrestore(&mac->lock, flags);
262 dprintk(KERN_INFO PFX "Unable to find matching network after scan!\n");
263 /* reset the retry counter for the next user request since we
264 * break out and don't reschedule ourselves after this point. */
265 mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
266 ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL);
271 /* reset the retry counter for the next user request since we
272 * now found a net and will try to associate to it, but not
273 * schedule this function again. */
274 mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
275 mac->associnfo.bssvalid = 1;
276 memcpy(mac->associnfo.bssid, found->bssid, ETH_ALEN);
277 /* copy the ESSID for displaying it */
278 mac->associnfo.associate_essid.len = found->essid.len;
279 memcpy(mac->associnfo.associate_essid.data, found->essid.data, IW_ESSID_MAX_SIZE + 1);
281 /* we found a network! authenticate (if necessary) and associate to it. */
282 if (!found->authenticated) {
283 /* This relies on the fact that _auth_req only queues the work,
284 * otherwise adding the notification would be racy. */
285 if (!ieee80211softmac_auth_req(mac, found)) {
286 dprintk(KERN_INFO PFX "cannot associate without being authenticated, requested authentication\n");
287 ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify, NULL, GFP_KERNEL);
289 printkl(KERN_WARNING PFX "Not authenticated, but requesting authentication failed. Giving up to associate\n");
290 ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found);
294 /* finally! now we can start associating */
295 ieee80211softmac_assoc(mac, found);
298 /* call this to do whatever is necessary when we're associated */
300 ieee80211softmac_associated(struct ieee80211softmac_device *mac,
301 struct ieee80211_assoc_response * resp,
302 struct ieee80211softmac_network *net)
304 mac->associnfo.associating = 0;
305 mac->associnfo.supported_rates = net->supported_rates;
306 ieee80211softmac_recalc_txrates(mac);
309 if (mac->set_bssid_filter)
310 mac->set_bssid_filter(mac->dev, net->bssid);
311 memcpy(mac->ieee->bssid, net->bssid, ETH_ALEN);
312 netif_carrier_on(mac->dev);
314 mac->association_id = le16_to_cpup(&resp->aid);
317 /* received frame handling functions */
319 ieee80211softmac_handle_assoc_response(struct net_device * dev,
320 struct ieee80211_assoc_response * resp,
321 struct ieee80211_network * _ieee80211_network_do_not_use)
323 /* NOTE: the network parameter has to be ignored by
324 * this code because it is the ieee80211's pointer
325 * to the struct, not ours (we made a copy)
327 struct ieee80211softmac_device *mac = ieee80211_priv(dev);
328 u16 status = le16_to_cpup(&resp->status);
329 struct ieee80211softmac_network *network = NULL;
332 if (unlikely(!mac->running))
335 spin_lock_irqsave(&mac->lock, flags);
337 if (!mac->associnfo.associating) {
338 /* we race against the timeout function, so make sure
339 * only one of us can do work */
340 spin_unlock_irqrestore(&mac->lock, flags);
343 network = ieee80211softmac_get_network_by_bssid_locked(mac, resp->header.addr3);
345 /* someone sending us things without us knowing him? Ignore. */
347 dprintk(KERN_INFO PFX "Received unrequested assocation response from " MAC_FMT "\n", MAC_ARG(resp->header.addr3));
348 spin_unlock_irqrestore(&mac->lock, flags);
352 /* now that we know it was for us, we can cancel the timeout */
353 cancel_delayed_work(&mac->associnfo.timeout);
357 dprintk(KERN_INFO PFX "associated!\n");
358 ieee80211softmac_associated(mac, resp, network);
359 ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATED, network);
361 case WLAN_REASON_STA_REQ_ASSOC_WITHOUT_AUTH:
362 if (!network->auth_desynced_once) {
363 /* there seem to be a few rare cases where our view of
364 * the world is obscured, or buggy APs that don't DEAUTH
365 * us properly. So we handle that, but allow it only once.
367 printkl(KERN_INFO PFX "We were not authenticated during association, retrying...\n");
368 network->authenticated = 0;
369 /* we don't want to do this more than once ... */
370 network->auth_desynced_once = 1;
371 schedule_work(&mac->associnfo.work);
375 dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status);
376 mac->associnfo.associating = 0;
377 mac->associnfo.bssvalid = 0;
379 ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network);
382 spin_unlock_irqrestore(&mac->lock, flags);
387 ieee80211softmac_handle_disassoc(struct net_device * dev,
388 struct ieee80211_disassoc *disassoc)
390 struct ieee80211softmac_device *mac = ieee80211_priv(dev);
392 if (unlikely(!mac->running))
395 if (memcmp(disassoc->header.addr2, mac->associnfo.bssid, ETH_ALEN))
398 if (memcmp(disassoc->header.addr1, mac->dev->dev_addr, ETH_ALEN))
401 dprintk(KERN_INFO PFX "got disassoc frame\n");
402 ieee80211softmac_disassoc(mac);
404 /* try to reassociate */
405 schedule_work(&mac->associnfo.work);
411 ieee80211softmac_handle_reassoc_req(struct net_device * dev,
412 struct ieee80211_reassoc_request * resp)
414 struct ieee80211softmac_device *mac = ieee80211_priv(dev);
415 struct ieee80211softmac_network *network;
417 if (unlikely(!mac->running))
420 network = ieee80211softmac_get_network_by_bssid(mac, resp->header.addr3);
422 dprintkl(KERN_INFO PFX "reassoc request from unknown network\n");
425 schedule_work(&mac->associnfo.work);