diff options
Diffstat (limited to 'net/mac80211/key.c')
-rw-r--r-- | net/mac80211/key.c | 243 |
1 files changed, 241 insertions, 2 deletions
diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 843d157..178f00c 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -2,25 +2,198 @@ * 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 <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; + + 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); + + WARN_ON(!ret && (key->conf.hw_key_idx == HW_KEY_IDX_INVALID)); + + 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, " MAC_FMT ") to hardware (%d)\n", + wiphy_name(key->local->hw.wiphy), + key->conf.keyidx, MAC_ARG(addr), ret); +} + +static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) +{ + const u8 *addr; + int ret; + + 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, " MAC_FMT ") from hardware (%d)\n", + wiphy_name(key->local->hw.wiphy), + key->conf.keyidx, MAC_ARG(addr), ret); + + key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; + key->conf.hw_key_idx = HW_KEY_IDX_INVALID; +} + struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, - int idx, size_t key_len, gfp_t flags) + struct sta_info *sta, + ieee80211_key_alg alg, + int idx, + size_t key_len, + const u8 *key_data) { struct ieee80211_key *key; - key = kzalloc(sizeof(struct ieee80211_key) + key_len, flags); + 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.hw_key_idx = HW_KEY_IDX_INVALID; + 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); + + if (sta) { + ieee80211_debugfs_key_sta_link(key, sta); + sta->key = key; + /* + * 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); + } + } + + if (idx >= 0 && idx < NUM_DEFAULT_KEYS) { + if (!sdata->keys[idx]) + sdata->keys[idx] = key; + else + WARN_ON(1); + } else + WARN_ON(1); + } + + list_add(&key->list, &sdata->key_list); + + if (netif_running(key->sdata->dev)) + ieee80211_key_enable_hw_accel(key); + return key; } @@ -29,8 +202,74 @@ void ieee80211_key_free(struct ieee80211_key *key) if (!key) return; + ieee80211_key_disable_hw_accel(key); + + if (key->sta) { + 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) + key->sdata->keys[key->conf.keyidx] = NULL; + else + WARN_ON(1); + } + 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); + + sdata->default_key = key; + + if (sdata->default_key) + ieee80211_debugfs_key_add_default(sdata); + + if (sdata->local->ops->set_key_idx) + sdata->local->ops->set_key_idx( + local_to_hw(sdata->local), idx); + } +} + +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); +} |