| /* |
| * Copyright 2002-2005, Instant802 Networks, Inc. |
| * Copyright 2005-2006, Devicescape Software, Inc. |
| * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> |
| * Copyright 2007-2008 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 <linux/rtnetlink.h> |
| #include <linux/slab.h> |
| #include <net/mac80211.h> |
| #include "ieee80211_i.h" |
| #include "driver-ops.h" |
| #include "debugfs_key.h" |
| #include "aes_ccm.h" |
| #include "aes_cmac.h" |
| |
| |
| /** |
| * 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, |
| * 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 key operations are protected internally. |
| * |
| * Within mac80211, key references are, just as STA structure references, |
| * protected by RCU. Note, however, that some things are unprotected, |
| * namely the key->sta dereferences within the hardware acceleration |
| * functions. This means that sta_info_destroy() must remove the key |
| * which waits for an RCU grace period. |
| */ |
| |
| static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; |
| |
| static void assert_key_lock(struct ieee80211_local *local) |
| { |
| WARN_ON(!mutex_is_locked(&local->key_mtx)); |
| } |
| |
| static struct ieee80211_sta *get_sta_for_key(struct ieee80211_key *key) |
| { |
| if (key->sta) |
| return &key->sta->sta; |
| |
| return NULL; |
| } |
| |
| static void ieee80211_key_enable_hw_accel(struct ieee80211_key *key) |
| { |
| struct ieee80211_sub_if_data *sdata; |
| struct ieee80211_sta *sta; |
| int ret; |
| |
| might_sleep(); |
| |
| if (!key->local->ops->set_key) |
| return; |
| |
| assert_key_lock(key->local); |
| |
| sta = get_sta_for_key(key); |
| |
| sdata = key->sdata; |
| if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) |
| sdata = container_of(sdata->bss, |
| struct ieee80211_sub_if_data, |
| u.ap); |
| |
| ret = drv_set_key(key->local, SET_KEY, sdata, sta, &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, %pM) to hardware (%d)\n", |
| wiphy_name(key->local->hw.wiphy), |
| key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); |
| } |
| |
| static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) |
| { |
| struct ieee80211_sub_if_data *sdata; |
| struct ieee80211_sta *sta; |
| int ret; |
| |
| might_sleep(); |
| |
| if (!key || !key->local->ops->set_key) |
| return; |
| |
| assert_key_lock(key->local); |
| |
| if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) |
| return; |
| |
| sta = get_sta_for_key(key); |
| sdata = key->sdata; |
| |
| if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) |
| sdata = container_of(sdata->bss, |
| struct ieee80211_sub_if_data, |
| u.ap); |
| |
| ret = drv_set_key(key->local, DISABLE_KEY, sdata, |
| sta, &key->conf); |
| |
| if (ret) |
| printk(KERN_ERR "mac80211-%s: failed to remove key " |
| "(%d, %pM) from hardware (%d)\n", |
| wiphy_name(key->local->hw.wiphy), |
| key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); |
| |
| key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; |
| } |
| |
| static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, |
| int idx) |
| { |
| struct ieee80211_key *key = NULL; |
| |
| assert_key_lock(sdata->local); |
| |
| if (idx >= 0 && idx < NUM_DEFAULT_KEYS) |
| key = sdata->keys[idx]; |
| |
| rcu_assign_pointer(sdata->default_key, key); |
| |
| if (key) { |
| ieee80211_debugfs_key_remove_default(key->sdata); |
| ieee80211_debugfs_key_add_default(key->sdata); |
| } |
| } |
| |
| void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx) |
| { |
| mutex_lock(&sdata->local->key_mtx); |
| __ieee80211_set_default_key(sdata, idx); |
| mutex_unlock(&sdata->local->key_mtx); |
| } |
| |
| static void |
| __ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, int idx) |
| { |
| struct ieee80211_key *key = NULL; |
| |
| assert_key_lock(sdata->local); |
| |
| if (idx >= NUM_DEFAULT_KEYS && |
| idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) |
| key = sdata->keys[idx]; |
| |
| rcu_assign_pointer(sdata->default_mgmt_key, key); |
| |
| if (key) { |
| ieee80211_debugfs_key_remove_mgmt_default(key->sdata); |
| ieee80211_debugfs_key_add_mgmt_default(key->sdata); |
| } |
| } |
| |
| void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata, |
| int idx) |
| { |
| mutex_lock(&sdata->local->key_mtx); |
| __ieee80211_set_default_mgmt_key(sdata, idx); |
| mutex_unlock(&sdata->local->key_mtx); |
| } |
| |
| |
| static void __ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, |
| struct sta_info *sta, |
| struct ieee80211_key *old, |
| struct ieee80211_key *new) |
| { |
| int idx, defkey, defmgmtkey; |
| |
| if (new) |
| list_add(&new->list, &sdata->key_list); |
| |
| if (sta) { |
| rcu_assign_pointer(sta->key, new); |
| } else { |
| WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx); |
| |
| if (old) |
| idx = old->conf.keyidx; |
| else |
| idx = new->conf.keyidx; |
| |
| defkey = old && sdata->default_key == old; |
| defmgmtkey = old && sdata->default_mgmt_key == old; |
| |
| if (defkey && !new) |
| __ieee80211_set_default_key(sdata, -1); |
| if (defmgmtkey && !new) |
| __ieee80211_set_default_mgmt_key(sdata, -1); |
| |
| rcu_assign_pointer(sdata->keys[idx], new); |
| if (defkey && new) |
| __ieee80211_set_default_key(sdata, new->conf.keyidx); |
| if (defmgmtkey && new) |
| __ieee80211_set_default_mgmt_key(sdata, |
| new->conf.keyidx); |
| } |
| |
| if (old) { |
| /* |
| * We'll use an empty list to indicate that the key |
| * has already been removed. |
| */ |
| list_del_init(&old->list); |
| } |
| } |
| |
| struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len, |
| const u8 *key_data, |
| size_t seq_len, const u8 *seq) |
| { |
| struct ieee80211_key *key; |
| int i, j, err; |
| |
| BUG_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS); |
| |
| key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL); |
| if (!key) |
| return ERR_PTR(-ENOMEM); |
| |
| /* |
| * Default to software encryption; we'll later upload the |
| * key to the hardware if possible. |
| */ |
| key->conf.flags = 0; |
| key->flags = 0; |
| |
| key->conf.cipher = cipher; |
| key->conf.keyidx = idx; |
| key->conf.keylen = key_len; |
| switch (cipher) { |
| case WLAN_CIPHER_SUITE_WEP40: |
| case WLAN_CIPHER_SUITE_WEP104: |
| key->conf.iv_len = WEP_IV_LEN; |
| key->conf.icv_len = WEP_ICV_LEN; |
| break; |
| case WLAN_CIPHER_SUITE_TKIP: |
| key->conf.iv_len = TKIP_IV_LEN; |
| key->conf.icv_len = TKIP_ICV_LEN; |
| if (seq) { |
| for (i = 0; i < NUM_RX_DATA_QUEUES; i++) { |
| key->u.tkip.rx[i].iv32 = |
| get_unaligned_le32(&seq[2]); |
| key->u.tkip.rx[i].iv16 = |
| get_unaligned_le16(seq); |
| } |
| } |
| break; |
| case WLAN_CIPHER_SUITE_CCMP: |
| key->conf.iv_len = CCMP_HDR_LEN; |
| key->conf.icv_len = CCMP_MIC_LEN; |
| if (seq) { |
| for (i = 0; i < NUM_RX_DATA_QUEUES + 1; i++) |
| for (j = 0; j < CCMP_PN_LEN; j++) |
| key->u.ccmp.rx_pn[i][j] = |
| seq[CCMP_PN_LEN - j - 1]; |
| } |
| /* |
| * 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 (IS_ERR(key->u.ccmp.tfm)) { |
| err = PTR_ERR(key->u.ccmp.tfm); |
| kfree(key); |
| key = ERR_PTR(err); |
| } |
| break; |
| case WLAN_CIPHER_SUITE_AES_CMAC: |
| key->conf.iv_len = 0; |
| key->conf.icv_len = sizeof(struct ieee80211_mmie); |
| if (seq) |
| for (j = 0; j < 6; j++) |
| key->u.aes_cmac.rx_pn[j] = seq[6 - j - 1]; |
| /* |
| * Initialize AES key state here as an optimization so that |
| * it does not need to be initialized for every packet. |
| */ |
| key->u.aes_cmac.tfm = |
| ieee80211_aes_cmac_key_setup(key_data); |
| if (IS_ERR(key->u.aes_cmac.tfm)) { |
| err = PTR_ERR(key->u.aes_cmac.tfm); |
| kfree(key); |
| key = ERR_PTR(err); |
| } |
| break; |
| } |
| memcpy(key->conf.key, key_data, key_len); |
| INIT_LIST_HEAD(&key->list); |
| |
| return key; |
| } |
| |
| static void __ieee80211_key_destroy(struct ieee80211_key *key) |
| { |
| if (!key) |
| return; |
| |
| if (key->local) |
| ieee80211_key_disable_hw_accel(key); |
| |
| if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP) |
| ieee80211_aes_key_free(key->u.ccmp.tfm); |
| if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC) |
| ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm); |
| if (key->local) |
| ieee80211_debugfs_key_remove(key); |
| |
| kfree(key); |
| } |
| |
| 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; |
| |
| BUG_ON(!sdata); |
| BUG_ON(!key); |
| |
| idx = key->conf.keyidx; |
| key->local = sdata->local; |
| key->sdata = sdata; |
| key->sta = sta; |
| |
| if (sta) { |
| /* |
| * some hardware cannot handle TKIP with QoS, so |
| * we indicate whether QoS could be in use. |
| */ |
| if (test_sta_flags(sta, WLAN_STA_WME)) |
| key->conf.flags |= IEEE80211_KEY_FLAG_WMM_STA; |
| |
| /* |
| * This key is for a specific sta interface, |
| * inform the driver that it should try to store |
| * this key as pairwise key. |
| */ |
| key->conf.flags |= IEEE80211_KEY_FLAG_PAIRWISE; |
| } else { |
| if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
| struct sta_info *ap; |
| |
| /* |
| * We're getting a sta pointer in, |
| * so must be under RCU read lock. |
| */ |
| |
| /* same here, the AP could be using QoS */ |
| ap = sta_info_get(key->sdata, key->sdata->u.mgd.bssid); |
| if (ap) { |
| if (test_sta_flags(ap, WLAN_STA_WME)) |
| key->conf.flags |= |
| IEEE80211_KEY_FLAG_WMM_STA; |
| } |
| } |
| } |
| |
| mutex_lock(&sdata->local->key_mtx); |
| |
| if (sta) |
| old_key = sta->key; |
| else |
| old_key = sdata->keys[idx]; |
| |
| __ieee80211_key_replace(sdata, sta, old_key, key); |
| __ieee80211_key_destroy(old_key); |
| |
| ieee80211_debugfs_key_add(key); |
| |
| ieee80211_key_enable_hw_accel(key); |
| |
| mutex_unlock(&sdata->local->key_mtx); |
| } |
| |
| static void __ieee80211_key_free(struct ieee80211_key *key) |
| { |
| /* |
| * Replace key with nothingness if it was ever used. |
| */ |
| if (key->sdata) |
| __ieee80211_key_replace(key->sdata, key->sta, |
| key, NULL); |
| __ieee80211_key_destroy(key); |
| } |
| |
| void ieee80211_key_free(struct ieee80211_local *local, |
| struct ieee80211_key *key) |
| { |
| if (!key) |
| return; |
| |
| mutex_lock(&local->key_mtx); |
| __ieee80211_key_free(key); |
| mutex_unlock(&local->key_mtx); |
| } |
| |
| void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_key *key; |
| |
| ASSERT_RTNL(); |
| |
| if (WARN_ON(!ieee80211_sdata_running(sdata))) |
| return; |
| |
| mutex_lock(&sdata->local->key_mtx); |
| |
| list_for_each_entry(key, &sdata->key_list, list) |
| ieee80211_key_enable_hw_accel(key); |
| |
| mutex_unlock(&sdata->local->key_mtx); |
| } |
| |
| void ieee80211_disable_keys(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_key *key; |
| |
| ASSERT_RTNL(); |
| |
| mutex_lock(&sdata->local->key_mtx); |
| |
| list_for_each_entry(key, &sdata->key_list, list) |
| ieee80211_key_disable_hw_accel(key); |
| |
| mutex_unlock(&sdata->local->key_mtx); |
| } |
| |
| void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata) |
| { |
| struct ieee80211_key *key, *tmp; |
| |
| mutex_lock(&sdata->local->key_mtx); |
| |
| ieee80211_debugfs_key_remove_default(sdata); |
| ieee80211_debugfs_key_remove_mgmt_default(sdata); |
| |
| list_for_each_entry_safe(key, tmp, &sdata->key_list, list) |
| __ieee80211_key_free(key); |
| |
| mutex_unlock(&sdata->local->key_mtx); |
| } |