| /* |
| * 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->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(void *d) |
| { |
| struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d; |
| struct ieee80211softmac_network *n; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&mac->lock, flags); |
| /* we might race against ieee80211softmac_handle_assoc_response, |
| * so make sure only one of us does something */ |
| if (!mac->associnfo.associating) { |
| spin_unlock_irqrestore(&mac->lock, flags); |
| return; |
| } |
| mac->associnfo.associating = 0; |
| mac->associnfo.bssvalid = 0; |
| mac->associated = 0; |
| |
| n = ieee80211softmac_get_network_by_bssid_locked(mac, mac->associnfo.bssid); |
| spin_unlock_irqrestore(&mac->lock, flags); |
| |
| dprintk(KERN_INFO PFX "assoc request timed out!\n"); |
| ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, n); |
| } |
| |
| 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->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->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((void*)mac); |
| } |
| |
| 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((void*)mac); |
| 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(void *d) |
| { |
| struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d; |
| struct ieee80211softmac_network *found = NULL; |
| struct ieee80211_network *net = NULL, *best = NULL; |
| int bssvalid; |
| unsigned long flags; |
| |
| /* ieee80211_disassoc might clear this */ |
| bssvalid = mac->associnfo.bssvalid; |
| |
| /* meh */ |
| if (mac->associated) |
| ieee80211softmac_send_disassoc_req(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT); |
| |
| spin_lock_irqsave(&mac->lock, flags); |
| mac->associnfo.associating = 1; |
| spin_unlock_irqrestore(&mac->lock, flags); |
| |
| /* 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) { |
| spin_lock_irqsave(&mac->lock, flags); |
| mac->associnfo.scan_retry--; |
| spin_unlock_irqrestore(&mac->lock, flags); |
| |
| /* 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"); |
| return; |
| } else { |
| spin_lock_irqsave(&mac->lock, flags); |
| mac->associnfo.associating = 0; |
| mac->associated = 0; |
| spin_unlock_irqrestore(&mac->lock, flags); |
| |
| 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); |
| return; |
| } |
| } |
| |
| /* 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); |
| } |
| return; |
| } |
| 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); |
| } |
| return; |
| } |
| /* finally! now we can start associating */ |
| mac->associnfo.assoc_wait = 0; |
| ieee80211softmac_assoc(mac, found); |
| } |
| |
| /* 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->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_work(&mac->associnfo.work); |
| break; |
| } |
| default: |
| dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status); |
| mac->associnfo.associating = 0; |
| mac->associnfo.bssvalid = 0; |
| mac->associated = 0; |
| ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network); |
| } |
| |
| spin_unlock_irqrestore(&mac->lock, flags); |
| return 0; |
| } |
| |
| 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); |
| |
| /* try to reassociate */ |
| schedule_work(&mac->associnfo.work); |
| |
| 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_work(&mac->associnfo.work); |
| |
| return 0; |
| } |