| /* | 
 |  * 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; | 
 | } |