[PATCH] wireless: Add softmac layer to the kernel

Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/ieee80211/softmac/ieee80211softmac_assoc.c b/net/ieee80211/softmac/ieee80211softmac_assoc.c
new file mode 100644
index 0000000..d491005
--- /dev/null
+++ b/net/ieee80211/softmac/ieee80211softmac_assoc.c
@@ -0,0 +1,356 @@
+#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;
+	function_enter();
+	/* 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 */
+	queue_delayed_work(mac->workqueue, &mac->associnfo.timeout, 5 * HZ);
+}
+
+void
+ieee80211softmac_assoc_timeout(void *d)
+{
+	struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d;
+	unsigned long flags;
+
+	function_enter();
+
+	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);
+}
+
+static void
+ieee80211softmac_reassoc(struct ieee80211softmac_device *mac)
+{
+	function_enter();
+}
+
+
+/* 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;
+	function_enter();
+
+	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;
+	
+	function_enter();
+	
+	/* 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 */
+	if (!found)
+	{
+		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 implement just finding one at all 
+			 *
+			 * 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;
+					continue;
+				}
+				/* we already had a matching network, so
+				 * compare their properties to get the
+				 * better of the two ... (see above)
+				 */
+				/* TODO */
+				/* for now, just */
+				break;
+			}
+		}
+		/* 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: Network not known, trying to initiate scan: ");
+			ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify, NULL);
+			if (ieee80211softmac_start_scan(mac))
+				dprintk("failed.\n");
+			else
+				dprintk("ok.\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 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);
+	mac->dev->flags |= IFF_RUNNING;
+	
+	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;
+				queue_work(mac->workqueue, &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;
+	dprintk(KERN_INFO PFX "got disassoc frame\n");
+	
+	spin_lock_irqsave(&mac->lock, flags);
+	mac->associnfo.bssvalid = 0;
+	mac->associated = 0;
+	spin_unlock_irqrestore(&mac->lock, flags);
+	
+	return 0;
+}