1 files changed, 279 insertions, 0 deletions
diff --git a/net/mac80211/key.c b/net/mac80211/key.c
new file mode 100644
index 00000000000..0b2328f7d67
--- /dev/null
+++ b/net/mac80211/key.c
@@ -0,0 +1,279 @@
+/*
+ * Copyright 2002-2005, Instant802 Networks, Inc.
+ * Copyright 2005-2006, Devicescape Software, Inc.
+ * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/if_ether.h>
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+#include <net/mac80211.h>
+#include "ieee80211_i.h"
+#include "debugfs_key.h"
+#include "aes_ccm.h"
+
+
+/*
+ * Key handling basics
+ *
+ * Key handling in mac80211 is done based on per-interface (sub_if_data)
+ * keys and per-station keys. Since each station belongs to an interface,
+ * each station key also belongs to that interface.
+ *
+ * Hardware acceleration is done on a best-effort basis, for each key
+ * that is eligible the hardware is asked to enable that key but if
+ * it cannot do that they key is simply kept for software encryption.
+ * There is currently no way of knowing this except by looking into
+ * debugfs.
+ *
+ * All operations here are called under RTNL so no extra locking is
+ * required.
+ */
+
+static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
+static const u8 zero_addr[ETH_ALEN];
+
+static const u8 *get_mac_for_key(struct ieee80211_key *key)
+{
+	const u8 *addr = bcast_addr;
+
+	/*
+	 * If we're an AP we won't ever receive frames with a non-WEP
+	 * group key so we tell the driver that by using the zero MAC
+	 * address to indicate a transmit-only key.
+	 */
+	if (key->conf.alg != ALG_WEP &&
+	    (key->sdata->type == IEEE80211_IF_TYPE_AP ||
+	     key->sdata->type == IEEE80211_IF_TYPE_VLAN))
+		addr = zero_addr;
+
+	if (key->sta)
+		addr = key->sta->addr;
+
+	return addr;
+}
+
+static void ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
+{
+	const u8 *addr;
+	int ret;
+	DECLARE_MAC_BUF(mac);
+
+	if (!key->local->ops->set_key)
+		return;
+
+	addr = get_mac_for_key(key);
+
+	ret = key->local->ops->set_key(local_to_hw(key->local), SET_KEY,
+				       key->sdata->dev->dev_addr, addr,
+				       &key->conf);
+
+	if (!ret)
+		key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
+
+	if (ret && ret != -ENOSPC && ret != -EOPNOTSUPP)
+		printk(KERN_ERR "mac80211-%s: failed to set key "
+		       "(%d, %s) to hardware (%d)\n",
+		       wiphy_name(key->local->hw.wiphy),
+		       key->conf.keyidx, print_mac(mac, addr), ret);
+}
+
+static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
+{
+	const u8 *addr;
+	int ret;
+	DECLARE_MAC_BUF(mac);
+
+	if (!key->local->ops->set_key)
+		return;
+
+	if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
+		return;
+
+	addr = get_mac_for_key(key);
+
+	ret = key->local->ops->set_key(local_to_hw(key->local), DISABLE_KEY,
+				       key->sdata->dev->dev_addr, addr,
+				       &key->conf);
+
+	if (ret)
+		printk(KERN_ERR "mac80211-%s: failed to remove key "
+		       "(%d, %s) from hardware (%d)\n",
+		       wiphy_name(key->local->hw.wiphy),
+		       key->conf.keyidx, print_mac(mac, addr), ret);
+
+	key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
+}
+
+struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata,
+					  struct sta_info *sta,
+					  enum ieee80211_key_alg alg,
+					  int idx,
+					  size_t key_len,
+					  const u8 *key_data)
+{
+	struct ieee80211_key *key;
+
+	BUG_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS);
+
+	key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
+	if (!key)
+		return NULL;
+
+	/*
+	 * Default to software encryption; we'll later upload the
+	 * key to the hardware if possible.
+	 */
+	key->conf.flags = 0;
+	key->flags = 0;
+
+	key->conf.alg = alg;
+	key->conf.keyidx = idx;
+	key->conf.keylen = key_len;
+	memcpy(key->conf.key, key_data, key_len);
+
+	key->local = sdata->local;
+	key->sdata = sdata;
+	key->sta = sta;
+
+	if (alg == ALG_CCMP) {
+		/*
+		 * Initialize AES key state here as an optimization so that
+		 * it does not need to be initialized for every packet.
+		 */
+		key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
+		if (!key->u.ccmp.tfm) {
+			ieee80211_key_free(key);
+			return NULL;
+		}
+	}
+
+	ieee80211_debugfs_key_add(key->local, key);
+
+	/* remove key first */
+	if (sta)
+		ieee80211_key_free(sta->key);
+	else
+		ieee80211_key_free(sdata->keys[idx]);
+
+	if (sta) {
+		ieee80211_debugfs_key_sta_link(key, sta);
+
+		/*
+		 * some hardware cannot handle TKIP with QoS, so
+		 * we indicate whether QoS could be in use.
+		 */
+		if (sta->flags & WLAN_STA_WME)
+			key->conf.flags |= IEEE80211_KEY_FLAG_WMM_STA;
+	} else {
+		if (sdata->type == IEEE80211_IF_TYPE_STA) {
+			struct sta_info *ap;
+
+			/* same here, the AP could be using QoS */
+			ap = sta_info_get(key->local, key->sdata->u.sta.bssid);
+			if (ap) {
+				if (ap->flags & WLAN_STA_WME)
+					key->conf.flags |=
+						IEEE80211_KEY_FLAG_WMM_STA;
+				sta_info_put(ap);
+			}
+		}
+	}
+
+	/* enable hwaccel if appropriate */
+	if (netif_running(key->sdata->dev))
+		ieee80211_key_enable_hw_accel(key);
+
+	if (sta)
+		rcu_assign_pointer(sta->key, key);
+	else
+		rcu_assign_pointer(sdata->keys[idx], key);
+
+	list_add(&key->list, &sdata->key_list);
+
+	return key;
+}
+
+void ieee80211_key_free(struct ieee80211_key *key)
+{
+	if (!key)
+		return;
+
+	if (key->sta) {
+		rcu_assign_pointer(key->sta->key, NULL);
+	} else {
+		if (key->sdata->default_key == key)
+			ieee80211_set_default_key(key->sdata, -1);
+		if (key->conf.keyidx >= 0 &&
+		    key->conf.keyidx < NUM_DEFAULT_KEYS)
+			rcu_assign_pointer(key->sdata->keys[key->conf.keyidx],
+					   NULL);
+		else
+			WARN_ON(1);
+	}
+
+	/* wait for all key users to complete */
+	synchronize_rcu();
+
+	/* remove from hwaccel if appropriate */
+	ieee80211_key_disable_hw_accel(key);
+
+	if (key->conf.alg == ALG_CCMP)
+		ieee80211_aes_key_free(key->u.ccmp.tfm);
+	ieee80211_debugfs_key_remove(key);
+
+	list_del(&key->list);
+
+	kfree(key);
+}
+
+void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx)
+{
+	struct ieee80211_key *key = NULL;
+
+	if (idx >= 0 && idx < NUM_DEFAULT_KEYS)
+		key = sdata->keys[idx];
+
+	if (sdata->default_key != key) {
+		ieee80211_debugfs_key_remove_default(sdata);
+
+		rcu_assign_pointer(sdata->default_key, key);
+
+		if (sdata->default_key)
+			ieee80211_debugfs_key_add_default(sdata);
+	}
+}
+
+void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_key *key, *tmp;
+
+	list_for_each_entry_safe(key, tmp, &sdata->key_list, list)
+		ieee80211_key_free(key);
+}
+
+void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_key *key;
+
+	WARN_ON(!netif_running(sdata->dev));
+	if (!netif_running(sdata->dev))
+		return;
+
+	list_for_each_entry(key, &sdata->key_list, list)
+		ieee80211_key_enable_hw_accel(key);
+}
+
+void ieee80211_disable_keys(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_key *key;
+
+	list_for_each_entry(key, &sdata->key_list, list)
+		ieee80211_key_disable_hw_accel(key);
+}