1 files changed, 396 insertions, 0 deletions

diff --git a/net/ieee80211/softmac/ieee80211softmac_assoc.c b/net/ieee80211/softmac/ieee80211softmac_assoc.c
new file mode 100644
index 000000000000..be61de78dfa4
--- /dev/null
+++ b/net/ieee80211/softmac/ieee80211softmac_assoc.c
@@ -0,0 +1,396 @@
+/*
+ * 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");
+
+        /* Change the state to associating */
+        spin_lock_irqsave(&mac->lock, flags);
+        mac->associnfo.associating = 1;
+        mac->associated = 0; /* just to make sure */
+        spin_unlock_irqrestore(&mac->lock, flags);
+
+        /* Set a timer for timeout */
+        /* FIXME: make timeout configurable */
+        schedule_delayed_work(&mac->associnfo.timeout, 5 * HZ);
+}
+
+void
+ieee80211softmac_assoc_timeout(void *d)
+{
+        struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d;
+        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;
+        spin_unlock_irqrestore(&mac->lock, flags);
+
+        dprintk(KERN_INFO PFX "assoc request timed out!\n");
+        /* FIXME: we need to know the network here. that requires a bit of restructuring */
+        ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, NULL);
+}
+
+/* Sends out a disassociation request to the desired AP */
+static void
+ieee80211softmac_disassoc(struct ieee80211softmac_device *mac, u16 reason)
+{
+        unsigned long flags;
+        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);
+        } else if (mac->associnfo.associating) {
+                cancel_delayed_work(&mac->associnfo.timeout);
+        }
+
+        /* Change our state */
+        spin_lock_irqsave(&mac->lock, flags);
+        /* Do NOT clear bssvalid as that will break ieee80211softmac_assoc_work! */
+        mac->associated = 0;
+        mac->associnfo.associating = 0;
+        spin_unlock_irqrestore(&mac->lock, flags);
+}
+
+static inline int
+we_support_all_basic_rates(struct ieee80211softmac_device *mac, u8 *from, u8 from_len)
+{
+        int idx, search, found;
+        u8 rate, search_rate;
+
+        for (idx = 0; idx < (from_len); idx++) {
+                rate = (from)[idx];
+                if (!(rate & IEEE80211_BASIC_RATE_MASK))
+                        continue;
+                found = 0;
+                rate &= ~IEEE80211_BASIC_RATE_MASK;
+                for (search = 0; search < mac->ratesinfo.count; search++) {
+                        search_rate = mac->ratesinfo.rates[search];
+                        search_rate &= ~IEEE80211_BASIC_RATE_MASK;
+                        if (rate == search_rate) {
+                                found = 1;
+                                break;
+                        }
+                }
+                if (!found)
+                        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;
+
+        /* 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(struct net_device *dev, void *context)
+{
+        struct ieee80211softmac_device *mac = ieee80211_priv(dev);
+        ieee80211softmac_assoc_work((void*)mac);
+}
+
+/* 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;
+        unsigned long flags;
+        
+        /* meh */
+        if (mac->associated)
+                ieee80211softmac_disassoc(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT);
+
+        /* try to find the requested network in our list, if we found one already */
+        if (mac->associnfo.bssvalid)
+                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, 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");
+                        ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL);
+                        return;
+                }
+        }
+        
+        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->authenticated) {
+                /* 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)) {
+                        dprintk(KERN_INFO PFX "cannot associate without being authenticated, requested authentication\n");
+                        ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify, NULL, GFP_KERNEL);
+                } else {
+                        printkl(KERN_WARNING PFX "Not authenticated, but requesting authentication failed. Giving up to associate\n");
+                        ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found);
+                }
+                return;
+        }
+        /* finally! now we can start associating */
+        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)
+{
+        mac->associnfo.associating = 0;
+        mac->associated = 1;
+        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_do_not_use)
+{
+        /* NOTE: the network parameter has to be 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;
+        
+        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);
+
+        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);
+        unsigned long flags;
+        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");
+        netif_carrier_off(dev);
+        spin_lock_irqsave(&mac->lock, flags);
+        mac->associnfo.bssvalid = 0;
+        mac->associated = 0;
+        schedule_work(&mac->associnfo.work);
+        spin_unlock_irqrestore(&mac->lock, flags);
+        
+        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;
+
+        network = ieee80211softmac_get_network_by_bssid(mac, resp->header.addr3);
+        if (!network) {
+                dprintkl(KERN_INFO PFX "reassoc request from unknown network\n");
+                return 0;
+        }
+        ieee80211softmac_assoc(mac, network);
+        return 0;
+}