net/ieee80211/softmac/ieee80211softmac_assoc.c - maze/linux - Git at Google

 /*
  * This file contains the softmac's association logic.
  *
  * Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
  *                          Joseph Jezak <josejx@gentoo.org>
  *                          Larry Finger <Larry.Finger@lwfinger.net>
  *                          Danny van Dyk <kugelfang@gentoo.org>
  *                          Michael Buesch <mbuesch@freenet.de>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License as
  * published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  *
  * The full GNU General Public License is included in this distribution in the
  * file called COPYING.
  */

 #include "ieee80211softmac_priv.h"

 /*
  * Overview
  *
  * Before you can associate, you have to authenticate.
  *
  */

 /* Sends out an association request to the desired AP */
 static void
 ieee80211softmac_assoc(struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 {
 	unsigned long flags;

 	/* Switch to correct channel for this network */
 	mac->set_channel(mac->dev, net->channel);

 	/* Send association request */
 	ieee80211softmac_send_mgt_frame(mac, net, IEEE80211_STYPE_ASSOC_REQ, 0);

 	dprintk(KERN_INFO PFX "sent association request!\n");

 	spin_lock_irqsave(&mac->lock, flags);
 	mac->associnfo.associated = 0; /* just to make sure */

 	/* Set a timer for timeout */
 	/* FIXME: make timeout configurable */
 	if (likely(mac->running))
 		schedule_delayed_work(&mac->associnfo.timeout, 5 * HZ);
 	spin_unlock_irqrestore(&mac->lock, flags);
 }

 void
 ieee80211softmac_assoc_timeout(struct work_struct *work)
 {
 	struct ieee80211softmac_device *mac =
 		container_of(work, struct ieee80211softmac_device,
 			     associnfo.timeout.work);
 	struct ieee80211softmac_network *n;

 	mutex_lock(&mac->associnfo.mutex);
 	/* we might race against ieee80211softmac_handle_assoc_response,
 	 * so make sure only one of us does something */
 	if (!mac->associnfo.associating)
 		goto out;
 	mac->associnfo.associating = 0;
 	mac->associnfo.bssvalid = 0;
 	mac->associnfo.associated = 0;

 	n = ieee80211softmac_get_network_by_bssid_locked(mac, mac->associnfo.bssid);

 	dprintk(KERN_INFO PFX "assoc request timed out!\n");
 	ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, n);
 out:
 	mutex_unlock(&mac->associnfo.mutex);
 }

 void
 ieee80211softmac_disassoc(struct ieee80211softmac_device *mac)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&mac->lock, flags);
 	if (mac->associnfo.associating)
 		cancel_delayed_work(&mac->associnfo.timeout);

 	netif_carrier_off(mac->dev);

 	mac->associnfo.associated = 0;
 	mac->associnfo.bssvalid = 0;
 	mac->associnfo.associating = 0;
 	ieee80211softmac_init_bss(mac);
 	ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_DISASSOCIATED, NULL);
 	spin_unlock_irqrestore(&mac->lock, flags);
 }

 /* Sends out a disassociation request to the desired AP */
 void
 ieee80211softmac_send_disassoc_req(struct ieee80211softmac_device *mac, u16 reason)
 {
 	struct ieee80211softmac_network *found;

 	if (mac->associnfo.bssvalid && mac->associnfo.associated) {
 		found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
 		if (found)
 			ieee80211softmac_send_mgt_frame(mac, found, IEEE80211_STYPE_DISASSOC, reason);
 	}

 	ieee80211softmac_disassoc(mac);
 }

 static inline int
 we_support_all_basic_rates(struct ieee80211softmac_device *mac, u8 *from, u8 from_len)
 {
 	int idx;
 	u8 rate;

 	for (idx = 0; idx < (from_len); idx++) {
 		rate = (from)[idx];
 		if (!(rate & IEEE80211_BASIC_RATE_MASK))
 			continue;
 		rate &= ~IEEE80211_BASIC_RATE_MASK;
 		if (!ieee80211softmac_ratesinfo_rate_supported(&mac->ratesinfo, rate))
 			return 0;
 	}
 	return 1;
 }

 static int
 network_matches_request(struct ieee80211softmac_device *mac, struct ieee80211_network *net)
 {
 	/* we cannot associate to networks whose name we don't know */
 	if (ieee80211_is_empty_essid(net->ssid, net->ssid_len))
 		return 0;
 	/* do not associate to a network whose BSSBasicRateSet we cannot support */
 	if (!we_support_all_basic_rates(mac, net->rates, net->rates_len))
 		return 0;
 	/* do we really need to check the ex rates? */
 	if (!we_support_all_basic_rates(mac, net->rates_ex, net->rates_ex_len))
 		return 0;

 	/* assume that users know what they're doing ...
 	 * (note we don't let them select a net we're incompatible with) */
 	if (mac->associnfo.bssfixed) {
 		return !memcmp(mac->associnfo.bssid, net->bssid, ETH_ALEN);
 	}

 	/* if 'ANY' network requested, take any that doesn't have privacy enabled */
 	if (mac->associnfo.req_essid.len == 0
 	    && !(net->capability & WLAN_CAPABILITY_PRIVACY))
 		return 1;
 	if (net->ssid_len != mac->associnfo.req_essid.len)
 		return 0;
 	if (!memcmp(net->ssid, mac->associnfo.req_essid.data, mac->associnfo.req_essid.len))
 		return 1;
 	return 0;
 }

 static void
 ieee80211softmac_assoc_notify_scan(struct net_device *dev, int event_type, void *context)
 {
 	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
 	ieee80211softmac_assoc_work(&mac->associnfo.work.work);
 }

 static void
 ieee80211softmac_assoc_notify_auth(struct net_device *dev, int event_type, void *context)
 {
 	struct ieee80211softmac_device *mac = ieee80211_priv(dev);

 	switch (event_type) {
 	case IEEE80211SOFTMAC_EVENT_AUTHENTICATED:
 		ieee80211softmac_assoc_work(&mac->associnfo.work.work);
 		break;
 	case IEEE80211SOFTMAC_EVENT_AUTH_FAILED:
 	case IEEE80211SOFTMAC_EVENT_AUTH_TIMEOUT:
 		ieee80211softmac_disassoc(mac);
 		break;
 	}
 }

 /* This function is called to handle userspace requests (asynchronously) */
 void
 ieee80211softmac_assoc_work(struct work_struct *work)
 {
 	struct ieee80211softmac_device *mac =
 		container_of(work, struct ieee80211softmac_device,
 			     associnfo.work.work);
 	struct ieee80211softmac_network *found = NULL;
 	struct ieee80211_network *net = NULL, *best = NULL;
 	int bssvalid;
 	unsigned long flags;

 	mutex_lock(&mac->associnfo.mutex);

 	if (!mac->associnfo.associating)
 		goto out;

 	/* ieee80211_disassoc might clear this */
 	bssvalid = mac->associnfo.bssvalid;

 	/* meh */
 	if (mac->associnfo.associated)
 		ieee80211softmac_send_disassoc_req(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT);

 	/* try to find the requested network in our list, if we found one already */
 	if (bssvalid || mac->associnfo.bssfixed)
 		found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);

 	/* Search the ieee80211 networks for this network if we didn't find it by bssid,
 	 * but only if we've scanned at least once (to get a better list of networks to
 	 * select from). If we have not scanned before, the !found logic below will be
 	 * invoked and will scan. */
 	if (!found && (mac->associnfo.scan_retry < IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT))
 	{
 		s8 rssi = -128;	/* if I don't initialise, gcc emits an invalid warning
 				   because it cannot follow the best pointer logic. */
 		spin_lock_irqsave(&mac->ieee->lock, flags);
 		list_for_each_entry(net, &mac->ieee->network_list, list) {
 			/* we're supposed to find the network with
 			 * the best signal here, as we're asked to join
 			 * any network with a specific ESSID, and many
 			 * different ones could have that.
 			 *
 			 * I'll for now just go with the reported rssi.
 			 *
 			 * We also should take into account the rateset
 			 * here to find the best BSSID to try.
 			 */
 			if (network_matches_request(mac, net)) {
 				if (!best) {
 					best = net;
 					rssi = best->stats.rssi;
 					continue;
 				}
 				/* we already had a matching network, so
 				 * compare their properties to get the
 				 * better of the two ... (see above)
 				 */
 				if (rssi < net->stats.rssi) {
 					best = net;
 					rssi = best->stats.rssi;
 				}
 			}
 		}
 		/* if we unlock here, we might get interrupted and the `best'
 		 * pointer could go stale */
 		if (best) {
 			found = ieee80211softmac_create_network(mac, best);
 			/* if found is still NULL, then we got -ENOMEM somewhere */
 			if (found)
 				ieee80211softmac_add_network(mac, found);
 		}
 		spin_unlock_irqrestore(&mac->ieee->lock, flags);
 	}

 	if (!found) {
 		if (mac->associnfo.scan_retry > 0) {
 			mac->associnfo.scan_retry--;

 			/* We know of no such network. Let's scan.
 			 * NB: this also happens if we had no memory to copy the network info...
 			 * Maybe we can hope to have more memory after scanning finishes ;)
 			 */
 			dprintk(KERN_INFO PFX "Associate: Scanning for networks first.\n");
 			ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify_scan, NULL);
 			if (ieee80211softmac_start_scan(mac))
 				dprintk(KERN_INFO PFX "Associate: failed to initiate scan. Is device up?\n");
 			goto out;
 		} else {
 			mac->associnfo.associating = 0;
 			mac->associnfo.associated = 0;

 			dprintk(KERN_INFO PFX "Unable to find matching network after scan!\n");
 			/* reset the retry counter for the next user request since we
 			 * break out and don't reschedule ourselves after this point. */
 			mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
 			ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL);
 			goto out;
 		}
 	}

 	/* reset the retry counter for the next user request since we
 	 * now found a net and will try to associate to it, but not
 	 * schedule this function again. */
 	mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
 	mac->associnfo.bssvalid = 1;
 	memcpy(mac->associnfo.bssid, found->bssid, ETH_ALEN);
 	/* copy the ESSID for displaying it */
 	mac->associnfo.associate_essid.len = found->essid.len;
 	memcpy(mac->associnfo.associate_essid.data, found->essid.data, IW_ESSID_MAX_SIZE + 1);

 	/* we found a network! authenticate (if necessary) and associate to it. */
 	if (found->authenticating) {
 		dprintk(KERN_INFO PFX "Already requested authentication, waiting...\n");
 		if(!mac->associnfo.assoc_wait) {
 			mac->associnfo.assoc_wait = 1;
 			ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify_auth, NULL, GFP_KERNEL);
 		}
 		goto out;
 	}
 	if (!found->authenticated && !found->authenticating) {
 		/* This relies on the fact that _auth_req only queues the work,
 		 * otherwise adding the notification would be racy. */
 		if (!ieee80211softmac_auth_req(mac, found)) {
 			if(!mac->associnfo.assoc_wait) {
 				dprintk(KERN_INFO PFX "Cannot associate without being authenticated, requested authentication\n");
 				mac->associnfo.assoc_wait = 1;
 				ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify_auth, NULL, GFP_KERNEL);
 			}
 		} else {
 			printkl(KERN_WARNING PFX "Not authenticated, but requesting authentication failed. Giving up to associate\n");
 			mac->associnfo.assoc_wait = 0;
 			ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found);
 		}
 		goto out;
 	}
 	/* finally! now we can start associating */
 	mac->associnfo.assoc_wait = 0;
 	ieee80211softmac_assoc(mac, found);

 out:
 	mutex_unlock(&mac->associnfo.mutex);
 }

 /* call this to do whatever is necessary when we're associated */
 static void
 ieee80211softmac_associated(struct ieee80211softmac_device *mac,
 	struct ieee80211_assoc_response * resp,
 	struct ieee80211softmac_network *net)
 {
 	u16 cap = le16_to_cpu(resp->capability);
 	u8 erp_value = net->erp_value;

 	mac->associnfo.associating = 0;
 	mac->bssinfo.supported_rates = net->supported_rates;
 	ieee80211softmac_recalc_txrates(mac);

 	mac->associnfo.associated = 1;

 	mac->associnfo.short_preamble_available =
 		(cap & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0;
 	ieee80211softmac_process_erp(mac, erp_value);

 	if (mac->set_bssid_filter)
 		mac->set_bssid_filter(mac->dev, net->bssid);
 	memcpy(mac->ieee->bssid, net->bssid, ETH_ALEN);
 	netif_carrier_on(mac->dev);

 	mac->association_id = le16_to_cpup(&resp->aid);
 }

 /* received frame handling functions */
 int
 ieee80211softmac_handle_assoc_response(struct net_device * dev,
 				       struct ieee80211_assoc_response * resp,
 				       struct ieee80211_network * _ieee80211_network)
 {
 	/* NOTE: the network parameter has to be mostly ignored by
 	 *       this code because it is the ieee80211's pointer
 	 *       to the struct, not ours (we made a copy)
 	 */
 	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
 	u16 status = le16_to_cpup(&resp->status);
 	struct ieee80211softmac_network *network = NULL;
 	unsigned long flags;

 	if (unlikely(!mac->running))
 		return -ENODEV;

 	spin_lock_irqsave(&mac->lock, flags);

 	if (!mac->associnfo.associating) {
 		/* we race against the timeout function, so make sure
 		 * only one of us can do work */
 		spin_unlock_irqrestore(&mac->lock, flags);
 		return 0;
 	}
 	network = ieee80211softmac_get_network_by_bssid_locked(mac, resp->header.addr3);

 	/* someone sending us things without us knowing him? Ignore. */
 	if (!network) {
 		dprintk(KERN_INFO PFX "Received unrequested assocation response from " MAC_FMT "\n", MAC_ARG(resp->header.addr3));
 		spin_unlock_irqrestore(&mac->lock, flags);
 		return 0;
 	}

 	/* now that we know it was for us, we can cancel the timeout */
 	cancel_delayed_work(&mac->associnfo.timeout);

 	/* if the association response included an ERP IE, update our saved
 	 * copy */
 	if (_ieee80211_network->flags & NETWORK_HAS_ERP_VALUE)
 		network->erp_value = _ieee80211_network->erp_value;

 	switch (status) {
 		case 0:
 			dprintk(KERN_INFO PFX "associated!\n");
 			ieee80211softmac_associated(mac, resp, network);
 			ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATED, network);
 			break;
 		case WLAN_REASON_STA_REQ_ASSOC_WITHOUT_AUTH:
 			if (!network->auth_desynced_once) {
 				/* there seem to be a few rare cases where our view of
 				 * the world is obscured, or buggy APs that don't DEAUTH
 				 * us properly. So we handle that, but allow it only once.
 				 */
 				printkl(KERN_INFO PFX "We were not authenticated during association, retrying...\n");
 				network->authenticated = 0;
 				/* we don't want to do this more than once ... */
 				network->auth_desynced_once = 1;
 				schedule_delayed_work(&mac->associnfo.work, 0);
 				break;
 			}
 		default:
 			dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status);
 			mac->associnfo.associating = 0;
 			mac->associnfo.bssvalid = 0;
 			mac->associnfo.associated = 0;
 			ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network);
 	}

 	spin_unlock_irqrestore(&mac->lock, flags);
 	return 0;
 }

 void
 ieee80211softmac_try_reassoc(struct ieee80211softmac_device *mac)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&mac->lock, flags);
 	mac->associnfo.associating = 1;
 	schedule_delayed_work(&mac->associnfo.work, 0);
 	spin_unlock_irqrestore(&mac->lock, flags);
 }

 int
 ieee80211softmac_handle_disassoc(struct net_device * dev,
 				 struct ieee80211_disassoc *disassoc)
 {
 	struct ieee80211softmac_device *mac = ieee80211_priv(dev);

 	if (unlikely(!mac->running))
 		return -ENODEV;

 	if (memcmp(disassoc->header.addr2, mac->associnfo.bssid, ETH_ALEN))
 		return 0;

 	if (memcmp(disassoc->header.addr1, mac->dev->dev_addr, ETH_ALEN))
 		return 0;

 	dprintk(KERN_INFO PFX "got disassoc frame\n");
 	ieee80211softmac_disassoc(mac);

 	ieee80211softmac_try_reassoc(mac);

 	return 0;
 }

 int
 ieee80211softmac_handle_reassoc_req(struct net_device * dev,
 				    struct ieee80211_reassoc_request * resp)
 {
 	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
 	struct ieee80211softmac_network *network;

 	if (unlikely(!mac->running))
 		return -ENODEV;

 	network = ieee80211softmac_get_network_by_bssid(mac, resp->header.addr3);
 	if (!network) {
 		dprintkl(KERN_INFO PFX "reassoc request from unknown network\n");
 		return 0;
 	}
 	schedule_delayed_work(&mac->associnfo.work, 0);

 	return 0;
 }
	/*
	* This file contains the softmac's association logic.
	*
	* Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
	* Joseph Jezak <josejx@gentoo.org>
	* Larry Finger <Larry.Finger@lwfinger.net>
	* Danny van Dyk <kugelfang@gentoo.org>
	* Michael Buesch <mbuesch@freenet.de>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of version 2 of the GNU General Public License as
	* published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*
	* The full GNU General Public License is included in this distribution in the
	* file called COPYING.
	*/

	#include "ieee80211softmac_priv.h"

	/*
	* Overview
	*
	* Before you can associate, you have to authenticate.
	*
	*/

	/* Sends out an association request to the desired AP */
	static void
	ieee80211softmac_assoc(struct ieee80211softmac_device mac, struct ieee80211softmac_network net)
	{
	unsigned long flags;

	/* Switch to correct channel for this network */
	mac->set_channel(mac->dev, net->channel);

	/* Send association request */
	ieee80211softmac_send_mgt_frame(mac, net, IEEE80211_STYPE_ASSOC_REQ, 0);

	dprintk(KERN_INFO PFX "sent association request!\n");

	spin_lock_irqsave(&mac->lock, flags);
	mac->associnfo.associated = 0; /* just to make sure */

	/* Set a timer for timeout */
	/* FIXME: make timeout configurable */
	if (likely(mac->running))
	schedule_delayed_work(&mac->associnfo.timeout, 5 * HZ);
	spin_unlock_irqrestore(&mac->lock, flags);
	}

	void
	ieee80211softmac_assoc_timeout(struct work_struct *work)
	{
	struct ieee80211softmac_device *mac =
	container_of(work, struct ieee80211softmac_device,
	associnfo.timeout.work);
	struct ieee80211softmac_network *n;

	mutex_lock(&mac->associnfo.mutex);
	/* we might race against ieee80211softmac_handle_assoc_response,
	* so make sure only one of us does something */
	if (!mac->associnfo.associating)
	goto out;
	mac->associnfo.associating = 0;
	mac->associnfo.bssvalid = 0;
	mac->associnfo.associated = 0;

	n = ieee80211softmac_get_network_by_bssid_locked(mac, mac->associnfo.bssid);

	dprintk(KERN_INFO PFX "assoc request timed out!\n");
	ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, n);
	out:
	mutex_unlock(&mac->associnfo.mutex);
	}

	void
	ieee80211softmac_disassoc(struct ieee80211softmac_device *mac)
	{
	unsigned long flags;

	spin_lock_irqsave(&mac->lock, flags);
	if (mac->associnfo.associating)
	cancel_delayed_work(&mac->associnfo.timeout);

	netif_carrier_off(mac->dev);

	mac->associnfo.associated = 0;
	mac->associnfo.bssvalid = 0;
	mac->associnfo.associating = 0;
	ieee80211softmac_init_bss(mac);
	ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_DISASSOCIATED, NULL);
	spin_unlock_irqrestore(&mac->lock, flags);
	}

	/* Sends out a disassociation request to the desired AP */
	void
	ieee80211softmac_send_disassoc_req(struct ieee80211softmac_device *mac, u16 reason)
	{
	struct ieee80211softmac_network *found;

	if (mac->associnfo.bssvalid && mac->associnfo.associated) {
	found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
	if (found)
	ieee80211softmac_send_mgt_frame(mac, found, IEEE80211_STYPE_DISASSOC, reason);
	}

	ieee80211softmac_disassoc(mac);
	}

	static inline int
	we_support_all_basic_rates(struct ieee80211softmac_device mac, u8 from, u8 from_len)
	{
	int idx;
	u8 rate;

	for (idx = 0; idx < (from_len); idx++) {
	rate = (from)[idx];
	if (!(rate & IEEE80211_BASIC_RATE_MASK))
	continue;
	rate &= ~IEEE80211_BASIC_RATE_MASK;
	if (!ieee80211softmac_ratesinfo_rate_supported(&mac->ratesinfo, rate))
	return 0;
	}
	return 1;
	}

	static int
	network_matches_request(struct ieee80211softmac_device mac, struct ieee80211_network net)
	{
	/* we cannot associate to networks whose name we don't know */
	if (ieee80211_is_empty_essid(net->ssid, net->ssid_len))
	return 0;
	/* do not associate to a network whose BSSBasicRateSet we cannot support */
	if (!we_support_all_basic_rates(mac, net->rates, net->rates_len))
	return 0;
	/* do we really need to check the ex rates? */
	if (!we_support_all_basic_rates(mac, net->rates_ex, net->rates_ex_len))
	return 0;

	/* assume that users know what they're doing ...
	* (note we don't let them select a net we're incompatible with) */
	if (mac->associnfo.bssfixed) {
	return !memcmp(mac->associnfo.bssid, net->bssid, ETH_ALEN);
	}

	/* if 'ANY' network requested, take any that doesn't have privacy enabled */
	if (mac->associnfo.req_essid.len == 0
	&& !(net->capability & WLAN_CAPABILITY_PRIVACY))
	return 1;
	if (net->ssid_len != mac->associnfo.req_essid.len)
	return 0;
	if (!memcmp(net->ssid, mac->associnfo.req_essid.data, mac->associnfo.req_essid.len))
	return 1;
	return 0;
	}

	static void
	ieee80211softmac_assoc_notify_scan(struct net_device dev, int event_type, void context)
	{
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
	ieee80211softmac_assoc_work(&mac->associnfo.work.work);
	}

	static void
	ieee80211softmac_assoc_notify_auth(struct net_device dev, int event_type, void context)
	{
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);

	switch (event_type) {
	case IEEE80211SOFTMAC_EVENT_AUTHENTICATED:
	ieee80211softmac_assoc_work(&mac->associnfo.work.work);
	break;
	case IEEE80211SOFTMAC_EVENT_AUTH_FAILED:
	case IEEE80211SOFTMAC_EVENT_AUTH_TIMEOUT:
	ieee80211softmac_disassoc(mac);
	break;
	}
	}

	/* This function is called to handle userspace requests (asynchronously) */
	void
	ieee80211softmac_assoc_work(struct work_struct *work)
	{
	struct ieee80211softmac_device *mac =
	container_of(work, struct ieee80211softmac_device,
	associnfo.work.work);
	struct ieee80211softmac_network *found = NULL;
	struct ieee80211_network net = NULL, best = NULL;
	int bssvalid;
	unsigned long flags;

	mutex_lock(&mac->associnfo.mutex);

	if (!mac->associnfo.associating)
	goto out;

	/* ieee80211_disassoc might clear this */
	bssvalid = mac->associnfo.bssvalid;

	/* meh */
	if (mac->associnfo.associated)
	ieee80211softmac_send_disassoc_req(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT);

	/* try to find the requested network in our list, if we found one already */
	if (bssvalid \|\| mac->associnfo.bssfixed)
	found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);

	/* Search the ieee80211 networks for this network if we didn't find it by bssid,
	* but only if we've scanned at least once (to get a better list of networks to
	* select from). If we have not scanned before, the !found logic below will be
	* invoked and will scan. */
	if (!found && (mac->associnfo.scan_retry < IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT))
	{
	s8 rssi = -128; /* if I don't initialise, gcc emits an invalid warning
	because it cannot follow the best pointer logic. */
	spin_lock_irqsave(&mac->ieee->lock, flags);
	list_for_each_entry(net, &mac->ieee->network_list, list) {
	/* we're supposed to find the network with
	* the best signal here, as we're asked to join
	* any network with a specific ESSID, and many
	* different ones could have that.
	*
	* I'll for now just go with the reported rssi.
	*
	* We also should take into account the rateset
	* here to find the best BSSID to try.
	*/
	if (network_matches_request(mac, net)) {
	if (!best) {
	best = net;
	rssi = best->stats.rssi;
	continue;
	}
	/* we already had a matching network, so
	* compare their properties to get the
	* better of the two ... (see above)
	*/
	if (rssi < net->stats.rssi) {
	best = net;
	rssi = best->stats.rssi;
	}
	}
	}
	/* if we unlock here, we might get interrupted and the `best'
	* pointer could go stale */
	if (best) {
	found = ieee80211softmac_create_network(mac, best);
	/* if found is still NULL, then we got -ENOMEM somewhere */
	if (found)
	ieee80211softmac_add_network(mac, found);
	}
	spin_unlock_irqrestore(&mac->ieee->lock, flags);
	}

	if (!found) {
	if (mac->associnfo.scan_retry > 0) {
	mac->associnfo.scan_retry--;

	/* We know of no such network. Let's scan.
	* NB: this also happens if we had no memory to copy the network info...
	* Maybe we can hope to have more memory after scanning finishes ;)
	*/
	dprintk(KERN_INFO PFX "Associate: Scanning for networks first.\n");
	ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify_scan, NULL);
	if (ieee80211softmac_start_scan(mac))
	dprintk(KERN_INFO PFX "Associate: failed to initiate scan. Is device up?\n");
	goto out;
	} else {
	mac->associnfo.associating = 0;
	mac->associnfo.associated = 0;

	dprintk(KERN_INFO PFX "Unable to find matching network after scan!\n");
	/* reset the retry counter for the next user request since we
	* break out and don't reschedule ourselves after this point. */
	mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
	ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL);
	goto out;
	}
	}

	/* reset the retry counter for the next user request since we
	* now found a net and will try to associate to it, but not
	* schedule this function again. */
	mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
	mac->associnfo.bssvalid = 1;
	memcpy(mac->associnfo.bssid, found->bssid, ETH_ALEN);
	/* copy the ESSID for displaying it */
	mac->associnfo.associate_essid.len = found->essid.len;
	memcpy(mac->associnfo.associate_essid.data, found->essid.data, IW_ESSID_MAX_SIZE + 1);

	/* we found a network! authenticate (if necessary) and associate to it. */
	if (found->authenticating) {
	dprintk(KERN_INFO PFX "Already requested authentication, waiting...\n");
	if(!mac->associnfo.assoc_wait) {
	mac->associnfo.assoc_wait = 1;
	ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify_auth, NULL, GFP_KERNEL);
	}
	goto out;
	}
	if (!found->authenticated && !found->authenticating) {
	/* This relies on the fact that _auth_req only queues the work,
	* otherwise adding the notification would be racy. */
	if (!ieee80211softmac_auth_req(mac, found)) {
	if(!mac->associnfo.assoc_wait) {
	dprintk(KERN_INFO PFX "Cannot associate without being authenticated, requested authentication\n");
	mac->associnfo.assoc_wait = 1;
	ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify_auth, NULL, GFP_KERNEL);
	}
	} else {
	printkl(KERN_WARNING PFX "Not authenticated, but requesting authentication failed. Giving up to associate\n");
	mac->associnfo.assoc_wait = 0;
	ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found);
	}
	goto out;
	}
	/* finally! now we can start associating */
	mac->associnfo.assoc_wait = 0;
	ieee80211softmac_assoc(mac, found);

	out:
	mutex_unlock(&mac->associnfo.mutex);
	}

	/* call this to do whatever is necessary when we're associated */
	static void
	ieee80211softmac_associated(struct ieee80211softmac_device *mac,
	struct ieee80211_assoc_response * resp,
	struct ieee80211softmac_network *net)
	{
	u16 cap = le16_to_cpu(resp->capability);
	u8 erp_value = net->erp_value;

	mac->associnfo.associating = 0;
	mac->bssinfo.supported_rates = net->supported_rates;
	ieee80211softmac_recalc_txrates(mac);

	mac->associnfo.associated = 1;

	mac->associnfo.short_preamble_available =
	(cap & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0;
	ieee80211softmac_process_erp(mac, erp_value);

	if (mac->set_bssid_filter)
	mac->set_bssid_filter(mac->dev, net->bssid);
	memcpy(mac->ieee->bssid, net->bssid, ETH_ALEN);
	netif_carrier_on(mac->dev);

	mac->association_id = le16_to_cpup(&resp->aid);
	}

	/* received frame handling functions */
	int
	ieee80211softmac_handle_assoc_response(struct net_device * dev,
	struct ieee80211_assoc_response * resp,
	struct ieee80211_network * _ieee80211_network)
	{
	/* NOTE: the network parameter has to be mostly ignored by
	* this code because it is the ieee80211's pointer
	* to the struct, not ours (we made a copy)
	*/
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
	u16 status = le16_to_cpup(&resp->status);
	struct ieee80211softmac_network *network = NULL;
	unsigned long flags;

	if (unlikely(!mac->running))
	return -ENODEV;

	spin_lock_irqsave(&mac->lock, flags);

	if (!mac->associnfo.associating) {
	/* we race against the timeout function, so make sure
	* only one of us can do work */
	spin_unlock_irqrestore(&mac->lock, flags);
	return 0;
	}
	network = ieee80211softmac_get_network_by_bssid_locked(mac, resp->header.addr3);

	/* someone sending us things without us knowing him? Ignore. */
	if (!network) {
	dprintk(KERN_INFO PFX "Received unrequested assocation response from " MAC_FMT "\n", MAC_ARG(resp->header.addr3));
	spin_unlock_irqrestore(&mac->lock, flags);
	return 0;
	}

	/* now that we know it was for us, we can cancel the timeout */
	cancel_delayed_work(&mac->associnfo.timeout);

	/* if the association response included an ERP IE, update our saved
	* copy */
	if (_ieee80211_network->flags & NETWORK_HAS_ERP_VALUE)
	network->erp_value = _ieee80211_network->erp_value;

	switch (status) {
	case 0:
	dprintk(KERN_INFO PFX "associated!\n");
	ieee80211softmac_associated(mac, resp, network);
	ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATED, network);
	break;
	case WLAN_REASON_STA_REQ_ASSOC_WITHOUT_AUTH:
	if (!network->auth_desynced_once) {
	/* there seem to be a few rare cases where our view of
	* the world is obscured, or buggy APs that don't DEAUTH
	* us properly. So we handle that, but allow it only once.
	*/
	printkl(KERN_INFO PFX "We were not authenticated during association, retrying...\n");
	network->authenticated = 0;
	/* we don't want to do this more than once ... */
	network->auth_desynced_once = 1;
	schedule_delayed_work(&mac->associnfo.work, 0);
	break;
	}
	default:
	dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status);
	mac->associnfo.associating = 0;
	mac->associnfo.bssvalid = 0;
	mac->associnfo.associated = 0;
	ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network);
	}

	spin_unlock_irqrestore(&mac->lock, flags);
	return 0;
	}

	void
	ieee80211softmac_try_reassoc(struct ieee80211softmac_device *mac)
	{
	unsigned long flags;

	spin_lock_irqsave(&mac->lock, flags);
	mac->associnfo.associating = 1;
	schedule_delayed_work(&mac->associnfo.work, 0);
	spin_unlock_irqrestore(&mac->lock, flags);
	}

	int
	ieee80211softmac_handle_disassoc(struct net_device * dev,
	struct ieee80211_disassoc *disassoc)
	{
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);

	if (unlikely(!mac->running))
	return -ENODEV;

	if (memcmp(disassoc->header.addr2, mac->associnfo.bssid, ETH_ALEN))
	return 0;

	if (memcmp(disassoc->header.addr1, mac->dev->dev_addr, ETH_ALEN))
	return 0;

	dprintk(KERN_INFO PFX "got disassoc frame\n");
	ieee80211softmac_disassoc(mac);

	ieee80211softmac_try_reassoc(mac);

	return 0;
	}

	int
	ieee80211softmac_handle_reassoc_req(struct net_device * dev,
	struct ieee80211_reassoc_request * resp)
	{
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
	struct ieee80211softmac_network *network;

	if (unlikely(!mac->running))
	return -ENODEV;

	network = ieee80211softmac_get_network_by_bssid(mac, resp->header.addr3);
	if (!network) {
	dprintkl(KERN_INFO PFX "reassoc request from unknown network\n");
	return 0;
	}
	schedule_delayed_work(&mac->associnfo.work, 0);

	return 0;
	}