| /* |
| * 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, |
| 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); |
| BUG_ON(alg == ALG_NONE); |
| |
| 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); |
| } |