X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=net%2Fmac80211%2Fkey.c;h=5df9e0cc009f2700f09d9ae63e80ece52f2bdbe0;hb=fadf6bf06069138f8e97c9a963be38348ba2708b;hp=0b2328f7d67cdb7b3bc90990f50e0450461d309c;hpb=4fa435018d740cb83d74c92306aa1f796da91ddd;p=linux-2.6-omap-h63xx.git diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 0b2328f7d67..5df9e0cc009 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -13,14 +13,15 @@ #include #include #include +#include #include #include "ieee80211_i.h" #include "debugfs_key.h" #include "aes_ccm.h" -/* - * Key handling basics +/** + * DOC: 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, @@ -34,6 +35,10 @@ * * All operations here are called under RTNL so no extra locking is * required. + * + * NOTE: This code requires that sta info *destruction* is done under + * RTNL, otherwise it can try to access already freed STA structs + * when a STA key is being freed. */ static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; @@ -49,8 +54,8 @@ static const u8 *get_mac_for_key(struct ieee80211_key *key) * 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)) + (key->sdata->vif.type == IEEE80211_IF_TYPE_AP || + key->sdata->vif.type == IEEE80211_IF_TYPE_VLAN)) addr = zero_addr; if (key->sta) @@ -68,6 +73,15 @@ static void ieee80211_key_enable_hw_accel(struct ieee80211_key *key) if (!key->local->ops->set_key) return; + /* + * This makes sure that all pending flushes have + * actually completed prior to uploading new key + * material to the hardware. That is necessary to + * avoid races between flushing STAs and adding + * new keys for them. + */ + __ieee80211_run_pending_flush(key->local); + addr = get_mac_for_key(key); ret = key->local->ops->set_key(local_to_hw(key->local), SET_KEY, @@ -84,16 +98,25 @@ static void ieee80211_key_enable_hw_accel(struct ieee80211_key *key) key->conf.keyidx, print_mac(mac, addr), ret); } +static void ieee80211_key_mark_hw_accel_off(struct ieee80211_key *key) +{ + if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { + key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; + key->flags |= KEY_FLAG_REMOVE_FROM_HARDWARE; + } +} + 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) + if (!key || !key->local->ops->set_key) return; - if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) + if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && + !(key->flags & KEY_FLAG_REMOVE_FROM_HARDWARE)) return; addr = get_mac_for_key(key); @@ -108,12 +131,11 @@ static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) wiphy_name(key->local->hw.wiphy), key->conf.keyidx, print_mac(mac, addr), ret); - key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; + key->flags &= ~(KEY_FLAG_UPLOADED_TO_HARDWARE | + KEY_FLAG_REMOVE_FROM_HARDWARE); } -struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, - struct sta_info *sta, - enum ieee80211_key_alg alg, +struct ieee80211_key *ieee80211_key_alloc(enum ieee80211_key_alg alg, int idx, size_t key_len, const u8 *key_data) @@ -137,10 +159,7 @@ struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, 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; + INIT_LIST_HEAD(&key->list); if (alg == ALG_CCMP) { /* @@ -154,13 +173,68 @@ struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, } } - ieee80211_debugfs_key_add(key->local, key); + return key; +} - /* remove key first */ - if (sta) - ieee80211_key_free(sta->key); - else - ieee80211_key_free(sdata->keys[idx]); +static void __ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, + struct sta_info *sta, + struct ieee80211_key *key, + struct ieee80211_key *new) +{ + int idx, defkey; + + if (new) + list_add(&new->list, &sdata->key_list); + + if (sta) { + rcu_assign_pointer(sta->key, new); + } else { + WARN_ON(new && key && new->conf.keyidx != key->conf.keyidx); + + if (key) + idx = key->conf.keyidx; + else + idx = new->conf.keyidx; + + defkey = key && sdata->default_key == key; + + if (defkey && !new) + ieee80211_set_default_key(sdata, -1); + + rcu_assign_pointer(sdata->keys[idx], new); + if (defkey && new) + ieee80211_set_default_key(sdata, new->conf.keyidx); + } + + if (key) { + ieee80211_key_mark_hw_accel_off(key); + /* + * We'll use an empty list to indicate that the key + * has already been removed. + */ + list_del_init(&key->list); + } +} + +void ieee80211_key_link(struct ieee80211_key *key, + struct ieee80211_sub_if_data *sdata, + struct sta_info *sta) +{ + struct ieee80211_key *old_key; + int idx; + + ASSERT_RTNL(); + might_sleep(); + + BUG_ON(!sdata); + BUG_ON(!key); + + idx = key->conf.keyidx; + key->local = sdata->local; + key->sdata = sdata; + key->sta = sta; + + ieee80211_debugfs_key_add(key->local, key); if (sta) { ieee80211_debugfs_key_sta_link(key, sta); @@ -172,64 +246,79 @@ struct ieee80211_key *ieee80211_key_alloc(struct ieee80211_sub_if_data *sdata, if (sta->flags & WLAN_STA_WME) key->conf.flags |= IEEE80211_KEY_FLAG_WMM_STA; } else { - if (sdata->type == IEEE80211_IF_TYPE_STA) { + if (sdata->vif.type == IEEE80211_IF_TYPE_STA) { struct sta_info *ap; + rcu_read_lock(); + /* 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); } + + rcu_read_unlock(); } } - /* enable hwaccel if appropriate */ - if (netif_running(key->sdata->dev)) - ieee80211_key_enable_hw_accel(key); - if (sta) - rcu_assign_pointer(sta->key, key); + old_key = sta->key; else - rcu_assign_pointer(sdata->keys[idx], key); + old_key = sdata->keys[idx]; - list_add(&key->list, &sdata->key_list); + __ieee80211_key_replace(sdata, sta, old_key, key); - return key; + if (old_key) { + synchronize_rcu(); + ieee80211_key_free(old_key); + } + + if (netif_running(sdata->dev)) + ieee80211_key_enable_hw_accel(key); } void ieee80211_key_free(struct ieee80211_key *key) { + ASSERT_RTNL(); + might_sleep(); + 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); - } + if (key->sdata) { + /* + * Replace key with nothingness. + * + * Because other code may have key reference (RCU protected) + * right now, we then wait for a grace period before freeing + * it. + * An empty list indicates it was never added to the key list + * or has been removed already. It may, however, still be in + * hardware for acceleration. + */ + if (!list_empty(&key->list)) + __ieee80211_key_replace(key->sdata, key->sta, + key, NULL); - /* wait for all key users to complete */ - synchronize_rcu(); + /* + * Do NOT remove this without looking at sta_info_destroy() + */ + synchronize_rcu(); - /* remove from hwaccel if appropriate */ - ieee80211_key_disable_hw_accel(key); + /* + * Remove from hwaccel if appropriate, this will + * only happen when the key is actually unlinked, + * it will already be done when the key was replaced. + */ + 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); } @@ -253,6 +342,10 @@ void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx) void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata) { struct ieee80211_key *key, *tmp; + LIST_HEAD(tmp_list); + + ASSERT_RTNL(); + might_sleep(); list_for_each_entry_safe(key, tmp, &sdata->key_list, list) ieee80211_key_free(key); @@ -262,8 +355,10 @@ 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)) + ASSERT_RTNL(); + might_sleep(); + + if (WARN_ON(!netif_running(sdata->dev))) return; list_for_each_entry(key, &sdata->key_list, list) @@ -274,6 +369,9 @@ void ieee80211_disable_keys(struct ieee80211_sub_if_data *sdata) { struct ieee80211_key *key; + ASSERT_RTNL(); + might_sleep(); + list_for_each_entry(key, &sdata->key_list, list) ieee80211_key_disable_hw_accel(key); }