// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2007-2008 Johannes Berg * Copyright 2013-2014 Intel Mobile Communications GmbH * Copyright 2015-2017 Intel Deutschland GmbH * Copyright 2018-2020, 2022 Intel Corporation */ #include #include #include #include #include #include #include #include #include #include #include "ieee80211_i.h" #include "driver-ops.h" #include "debugfs_key.h" #include "aes_ccm.h" #include "aes_cmac.h" #include "aes_gmac.h" #include "aes_gcm.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 algorithms * that are implemented in software, for each key the hardware is asked * to enable that key for offloading but if it cannot do that the key is * simply kept for software encryption (unless it is for an algorithm * that isn't implemented in software). * There is currently no way of knowing whether a key is handled in SW * or HW except by looking into debugfs. * * All key management is internally protected by a mutex. Within all * other parts of 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) { lockdep_assert_held(&local->key_mtx); } static void update_vlan_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta) { struct ieee80211_sub_if_data *vlan; if (sdata->vif.type != NL80211_IFTYPE_AP) return; /* crypto_tx_tailroom_needed_cnt is protected by this */ assert_key_lock(sdata->local); rcu_read_lock(); list_for_each_entry_rcu(vlan, &sdata->u.ap.vlans, u.vlan.list) vlan->crypto_tx_tailroom_needed_cnt += delta; rcu_read_unlock(); } static void increment_tailroom_need_count(struct ieee80211_sub_if_data *sdata) { /* * When this count is zero, SKB resizing for allocating tailroom * for IV or MMIC is skipped. But, this check has created two race * cases in xmit path while transiting from zero count to one: * * 1. SKB resize was skipped because no key was added but just before * the xmit key is added and SW encryption kicks off. * * 2. SKB resize was skipped because all the keys were hw planted but * just before xmit one of the key is deleted and SW encryption kicks * off. * * In both the above case SW encryption will find not enough space for * tailroom and exits with WARN_ON. (See WARN_ONs at wpa.c) * * Solution has been explained at * http://mid.gmane.org/1308590980.4322.19.camel@jlt3.sipsolutions.net */ assert_key_lock(sdata->local); update_vlan_tailroom_need_count(sdata, 1); if (!sdata->crypto_tx_tailroom_needed_cnt++) { /* * Flush all XMIT packets currently using HW encryption or no * encryption at all if the count transition is from 0 -> 1. */ synchronize_net(); } } static void decrease_tailroom_need_count(struct ieee80211_sub_if_data *sdata, int delta) { assert_key_lock(sdata->local); WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt < delta); update_vlan_tailroom_need_count(sdata, -delta); sdata->crypto_tx_tailroom_needed_cnt -= delta; } static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key) { struct ieee80211_sub_if_data *sdata = key->sdata; struct sta_info *sta; int ret = -EOPNOTSUPP; might_sleep(); if (key->flags & KEY_FLAG_TAINTED) { /* If we get here, it's during resume and the key is * tainted so shouldn't be used/programmed any more. * However, its flags may still indicate that it was * programmed into the device (since we're in resume) * so clear that flag now to avoid trying to remove * it again later. */ if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE && !(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | IEEE80211_KEY_FLAG_PUT_MIC_SPACE | IEEE80211_KEY_FLAG_RESERVE_TAILROOM))) increment_tailroom_need_count(sdata); key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; return -EINVAL; } if (!key->local->ops->set_key) goto out_unsupported; assert_key_lock(key->local); sta = key->sta; /* * If this is a per-STA GTK, check if it * is supported; if not, return. */ if (sta && !(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE) && !ieee80211_hw_check(&key->local->hw, SUPPORTS_PER_STA_GTK)) goto out_unsupported; if (sta && !sta->uploaded) goto out_unsupported; if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) { /* * The driver doesn't know anything about VLAN interfaces. * Hence, don't send GTKs for VLAN interfaces to the driver. */ if (!(key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) { ret = 1; goto out_unsupported; } } if (key->conf.link_id >= 0 && sdata->vif.active_links && !(sdata->vif.active_links & BIT(key->conf.link_id))) return 0; ret = drv_set_key(key->local, SET_KEY, sdata, sta ? &sta->sta : NULL, &key->conf); if (!ret) { key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE; if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | IEEE80211_KEY_FLAG_PUT_MIC_SPACE | IEEE80211_KEY_FLAG_RESERVE_TAILROOM))) decrease_tailroom_need_count(sdata, 1); WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) && (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)); WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) && (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)); return 0; } if (ret != -ENOSPC && ret != -EOPNOTSUPP && ret != 1) sdata_err(sdata, "failed to set key (%d, %pM) to hardware (%d)\n", key->conf.keyidx, sta ? sta->sta.addr : bcast_addr, ret); out_unsupported: switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_WEP40: case WLAN_CIPHER_SUITE_WEP104: case WLAN_CIPHER_SUITE_TKIP: case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: /* all of these we can do in software - if driver can */ if (ret == 1) return 0; if (ieee80211_hw_check(&key->local->hw, SW_CRYPTO_CONTROL)) return -EINVAL; return 0; default: return -EINVAL; } } static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) { struct ieee80211_sub_if_data *sdata; struct sta_info *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 = key->sta; sdata = key->sdata; if (key->conf.link_id >= 0 && sdata->vif.active_links && !(sdata->vif.active_links & BIT(key->conf.link_id))) return; if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | IEEE80211_KEY_FLAG_PUT_MIC_SPACE | IEEE80211_KEY_FLAG_RESERVE_TAILROOM))) increment_tailroom_need_count(sdata); key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; ret = drv_set_key(key->local, DISABLE_KEY, sdata, sta ? &sta->sta : NULL, &key->conf); if (ret) sdata_err(sdata, "failed to remove key (%d, %pM) from hardware (%d)\n", key->conf.keyidx, sta ? sta->sta.addr : bcast_addr, ret); } static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force) { struct sta_info *sta = key->sta; struct ieee80211_local *local = key->local; assert_key_lock(local); set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION); sta->ptk_idx = key->conf.keyidx; if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) clear_sta_flag(sta, WLAN_STA_BLOCK_BA); ieee80211_check_fast_xmit(sta); return 0; } int ieee80211_set_tx_key(struct ieee80211_key *key) { return _ieee80211_set_tx_key(key, false); } static void ieee80211_pairwise_rekey(struct ieee80211_key *old, struct ieee80211_key *new) { struct ieee80211_local *local = new->local; struct sta_info *sta = new->sta; int i; assert_key_lock(local); if (new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX) { /* Extended Key ID key install, initial one or rekey */ if (sta->ptk_idx != INVALID_PTK_KEYIDX && !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT)) { /* Aggregation Sessions with Extended Key ID must not * mix MPDUs with different keyIDs within one A-MPDU. * Tear down running Tx aggregation sessions and block * new Rx/Tx aggregation requests during rekey to * ensure there are no A-MPDUs when the driver is not * supporting A-MPDU key borders. (Blocking Tx only * would be sufficient but WLAN_STA_BLOCK_BA gets the * job done for the few ms we need it.) */ set_sta_flag(sta, WLAN_STA_BLOCK_BA); mutex_lock(&sta->ampdu_mlme.mtx); for (i = 0; i < IEEE80211_NUM_TIDS; i++) ___ieee80211_stop_tx_ba_session(sta, i, AGG_STOP_LOCAL_REQUEST); mutex_unlock(&sta->ampdu_mlme.mtx); } } else if (old) { /* Rekey without Extended Key ID. * Aggregation sessions are OK when running on SW crypto. * A broken remote STA may cause issues not observed with HW * crypto, though. */ if (!(old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) return; /* Stop Tx till we are on the new key */ old->flags |= KEY_FLAG_TAINTED; ieee80211_clear_fast_xmit(sta); if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) { set_sta_flag(sta, WLAN_STA_BLOCK_BA); ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_LOCAL_REQUEST); } if (!wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_CAN_REPLACE_PTK0)) { pr_warn_ratelimited("Rekeying PTK for STA %pM but driver can't safely do that.", sta->sta.addr); /* Flushing the driver queues *may* help prevent * the clear text leaks and freezes. */ ieee80211_flush_queues(local, old->sdata, false); } } } static void __ieee80211_set_default_key(struct ieee80211_link_data *link, int idx, bool uni, bool multi) { struct ieee80211_sub_if_data *sdata = link->sdata; struct ieee80211_key *key = NULL; assert_key_lock(sdata->local); if (idx >= 0 && idx < NUM_DEFAULT_KEYS) { key = key_mtx_dereference(sdata->local, sdata->keys[idx]); if (!key) key = key_mtx_dereference(sdata->local, link->gtk[idx]); } if (uni) { rcu_assign_pointer(sdata->default_unicast_key, key); ieee80211_check_fast_xmit_iface(sdata); if (sdata->vif.type != NL80211_IFTYPE_AP_VLAN) drv_set_default_unicast_key(sdata->local, sdata, idx); } if (multi) rcu_assign_pointer(link->default_multicast_key, key); ieee80211_debugfs_key_update_default(sdata); } void ieee80211_set_default_key(struct ieee80211_link_data *link, int idx, bool uni, bool multi) { mutex_lock(&link->sdata->local->key_mtx); __ieee80211_set_default_key(link, idx, uni, multi); mutex_unlock(&link->sdata->local->key_mtx); } static void __ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link, int idx) { struct ieee80211_sub_if_data *sdata = link->sdata; struct ieee80211_key *key = NULL; assert_key_lock(sdata->local); if (idx >= NUM_DEFAULT_KEYS && idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) key = key_mtx_dereference(sdata->local, link->gtk[idx]); rcu_assign_pointer(link->default_mgmt_key, key); ieee80211_debugfs_key_update_default(sdata); } void ieee80211_set_default_mgmt_key(struct ieee80211_link_data *link, int idx) { mutex_lock(&link->sdata->local->key_mtx); __ieee80211_set_default_mgmt_key(link, idx); mutex_unlock(&link->sdata->local->key_mtx); } static void __ieee80211_set_default_beacon_key(struct ieee80211_link_data *link, int idx) { struct ieee80211_sub_if_data *sdata = link->sdata; struct ieee80211_key *key = NULL; assert_key_lock(sdata->local); if (idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS && idx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS + NUM_DEFAULT_BEACON_KEYS) key = key_mtx_dereference(sdata->local, link->gtk[idx]); rcu_assign_pointer(link->default_beacon_key, key); ieee80211_debugfs_key_update_default(sdata); } void ieee80211_set_default_beacon_key(struct ieee80211_link_data *link, int idx) { mutex_lock(&link->sdata->local->key_mtx); __ieee80211_set_default_beacon_key(link, idx); mutex_unlock(&link->sdata->local->key_mtx); } static int ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, struct ieee80211_link_data *link, struct sta_info *sta, bool pairwise, struct ieee80211_key *old, struct ieee80211_key *new) { struct link_sta_info *link_sta = sta ? &sta->deflink : NULL; int link_id; int idx; int ret = 0; bool defunikey, defmultikey, defmgmtkey, defbeaconkey; bool is_wep; /* caller must provide at least one old/new */ if (WARN_ON(!new && !old)) return 0; if (new) { idx = new->conf.keyidx; is_wep = new->conf.cipher == WLAN_CIPHER_SUITE_WEP40 || new->conf.cipher == WLAN_CIPHER_SUITE_WEP104; link_id = new->conf.link_id; } else { idx = old->conf.keyidx; is_wep = old->conf.cipher == WLAN_CIPHER_SUITE_WEP40 || old->conf.cipher == WLAN_CIPHER_SUITE_WEP104; link_id = old->conf.link_id; } if (WARN(old && old->conf.link_id != link_id, "old link ID %d doesn't match new link ID %d\n", old->conf.link_id, link_id)) return -EINVAL; if (link_id >= 0) { if (!link) { link = sdata_dereference(sdata->link[link_id], sdata); if (!link) return -ENOLINK; } if (sta) { link_sta = rcu_dereference_protected(sta->link[link_id], lockdep_is_held(&sta->local->sta_mtx)); if (!link_sta) return -ENOLINK; } } else { link = &sdata->deflink; } if ((is_wep || pairwise) && idx >= NUM_DEFAULT_KEYS) return -EINVAL; WARN_ON(new && old && new->conf.keyidx != old->conf.keyidx); if (new && sta && pairwise) { /* Unicast rekey needs special handling. With Extended Key ID * old is still NULL for the first rekey. */ ieee80211_pairwise_rekey(old, new); } if (old) { if (old->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { ieee80211_key_disable_hw_accel(old); if (new) ret = ieee80211_key_enable_hw_accel(new); } } else { if (!new->local->wowlan) ret = ieee80211_key_enable_hw_accel(new); } if (ret) return ret; if (new) list_add_tail_rcu(&new->list, &sdata->key_list); if (sta) { if (pairwise) { rcu_assign_pointer(sta->ptk[idx], new); if (new && !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX)) _ieee80211_set_tx_key(new, true); } else { rcu_assign_pointer(link_sta->gtk[idx], new); } /* Only needed for transition from no key -> key. * Still triggers unnecessary when using Extended Key ID * and installing the second key ID the first time. */ if (new && !old) ieee80211_check_fast_rx(sta); } else { defunikey = old && old == key_mtx_dereference(sdata->local, sdata->default_unicast_key); defmultikey = old && old == key_mtx_dereference(sdata->local, link->default_multicast_key); defmgmtkey = old && old == key_mtx_dereference(sdata->local, link->default_mgmt_key); defbeaconkey = old && old == key_mtx_dereference(sdata->local, link->default_beacon_key); if (defunikey && !new) __ieee80211_set_default_key(link, -1, true, false); if (defmultikey && !new) __ieee80211_set_default_key(link, -1, false, true); if (defmgmtkey && !new) __ieee80211_set_default_mgmt_key(link, -1); if (defbeaconkey && !new) __ieee80211_set_default_beacon_key(link, -1); if (is_wep || pairwise) rcu_assign_pointer(sdata->keys[idx], new); else rcu_assign_pointer(link->gtk[idx], new); if (defunikey && new) __ieee80211_set_default_key(link, new->conf.keyidx, true, false); if (defmultikey && new) __ieee80211_set_default_key(link, new->conf.keyidx, false, true); if (defmgmtkey && new) __ieee80211_set_default_mgmt_key(link, new->conf.keyidx); if (defbeaconkey && new) __ieee80211_set_default_beacon_key(link, new->conf.keyidx); } if (old) list_del_rcu(&old->list); return 0; } 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; if (WARN_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS + NUM_DEFAULT_BEACON_KEYS)) return ERR_PTR(-EINVAL); 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.link_id = -1; 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 = IEEE80211_WEP_IV_LEN; key->conf.icv_len = IEEE80211_WEP_ICV_LEN; break; case WLAN_CIPHER_SUITE_TKIP: key->conf.iv_len = IEEE80211_TKIP_IV_LEN; key->conf.icv_len = IEEE80211_TKIP_ICV_LEN; if (seq) { for (i = 0; i < IEEE80211_NUM_TIDS; i++) { key->u.tkip.rx[i].iv32 = get_unaligned_le32(&seq[2]); key->u.tkip.rx[i].iv16 = get_unaligned_le16(seq); } } spin_lock_init(&key->u.tkip.txlock); break; case WLAN_CIPHER_SUITE_CCMP: key->conf.iv_len = IEEE80211_CCMP_HDR_LEN; key->conf.icv_len = IEEE80211_CCMP_MIC_LEN; if (seq) { for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++) for (j = 0; j < IEEE80211_CCMP_PN_LEN; j++) key->u.ccmp.rx_pn[i][j] = seq[IEEE80211_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, key_len, IEEE80211_CCMP_MIC_LEN); if (IS_ERR(key->u.ccmp.tfm)) { err = PTR_ERR(key->u.ccmp.tfm); kfree(key); return ERR_PTR(err); } break; case WLAN_CIPHER_SUITE_CCMP_256: key->conf.iv_len = IEEE80211_CCMP_256_HDR_LEN; key->conf.icv_len = IEEE80211_CCMP_256_MIC_LEN; for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++) for (j = 0; j < IEEE80211_CCMP_256_PN_LEN; j++) key->u.ccmp.rx_pn[i][j] = seq[IEEE80211_CCMP_256_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, key_len, IEEE80211_CCMP_256_MIC_LEN); if (IS_ERR(key->u.ccmp.tfm)) { err = PTR_ERR(key->u.ccmp.tfm); kfree(key); return ERR_PTR(err); } break; case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: key->conf.iv_len = 0; if (cipher == WLAN_CIPHER_SUITE_AES_CMAC) key->conf.icv_len = sizeof(struct ieee80211_mmie); else key->conf.icv_len = sizeof(struct ieee80211_mmie_16); if (seq) for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++) key->u.aes_cmac.rx_pn[j] = seq[IEEE80211_CMAC_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.aes_cmac.tfm = ieee80211_aes_cmac_key_setup(key_data, key_len); if (IS_ERR(key->u.aes_cmac.tfm)) { err = PTR_ERR(key->u.aes_cmac.tfm); kfree(key); return ERR_PTR(err); } break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: key->conf.iv_len = 0; key->conf.icv_len = sizeof(struct ieee80211_mmie_16); if (seq) for (j = 0; j < IEEE80211_GMAC_PN_LEN; j++) key->u.aes_gmac.rx_pn[j] = seq[IEEE80211_GMAC_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.aes_gmac.tfm = ieee80211_aes_gmac_key_setup(key_data, key_len); if (IS_ERR(key->u.aes_gmac.tfm)) { err = PTR_ERR(key->u.aes_gmac.tfm); kfree(key); return ERR_PTR(err); } break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: key->conf.iv_len = IEEE80211_GCMP_HDR_LEN; key->conf.icv_len = IEEE80211_GCMP_MIC_LEN; for (i = 0; seq && i < IEEE80211_NUM_TIDS + 1; i++) for (j = 0; j < IEEE80211_GCMP_PN_LEN; j++) key->u.gcmp.rx_pn[i][j] = seq[IEEE80211_GCMP_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.gcmp.tfm = ieee80211_aes_gcm_key_setup_encrypt(key_data, key_len); if (IS_ERR(key->u.gcmp.tfm)) { err = PTR_ERR(key->u.gcmp.tfm); kfree(key); return ERR_PTR(err); } break; } memcpy(key->conf.key, key_data, key_len); INIT_LIST_HEAD(&key->list); return key; } static void ieee80211_key_free_common(struct ieee80211_key *key) { switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: ieee80211_aes_key_free(key->u.ccmp.tfm); break; case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm); break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: ieee80211_aes_gmac_key_free(key->u.aes_gmac.tfm); break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: ieee80211_aes_gcm_key_free(key->u.gcmp.tfm); break; } kfree_sensitive(key); } static void __ieee80211_key_destroy(struct ieee80211_key *key, bool delay_tailroom) { if (key->local) { struct ieee80211_sub_if_data *sdata = key->sdata; ieee80211_debugfs_key_remove(key); if (delay_tailroom) { /* see ieee80211_delayed_tailroom_dec */ sdata->crypto_tx_tailroom_pending_dec++; schedule_delayed_work(&sdata->dec_tailroom_needed_wk, HZ/2); } else { decrease_tailroom_need_count(sdata, 1); } } ieee80211_key_free_common(key); } static void ieee80211_key_destroy(struct ieee80211_key *key, bool delay_tailroom) { if (!key) return; /* * Synchronize so the TX path and rcu key iterators * can no longer be using this key before we free/remove it. */ synchronize_net(); __ieee80211_key_destroy(key, delay_tailroom); } void ieee80211_key_free_unused(struct ieee80211_key *key) { WARN_ON(key->sdata || key->local); ieee80211_key_free_common(key); } static bool ieee80211_key_identical(struct ieee80211_sub_if_data *sdata, struct ieee80211_key *old, struct ieee80211_key *new) { u8 tkip_old[WLAN_KEY_LEN_TKIP], tkip_new[WLAN_KEY_LEN_TKIP]; u8 *tk_old, *tk_new; if (!old || new->conf.keylen != old->conf.keylen) return false; tk_old = old->conf.key; tk_new = new->conf.key; /* * In station mode, don't compare the TX MIC key, as it's never used * and offloaded rekeying may not care to send it to the host. This * is the case in iwlwifi, for example. */ if (sdata->vif.type == NL80211_IFTYPE_STATION && new->conf.cipher == WLAN_CIPHER_SUITE_TKIP && new->conf.keylen == WLAN_KEY_LEN_TKIP && !(new->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE)) { memcpy(tkip_old, tk_old, WLAN_KEY_LEN_TKIP); memcpy(tkip_new, tk_new, WLAN_KEY_LEN_TKIP); memset(tkip_old + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8); memset(tkip_new + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY, 0, 8); tk_old = tkip_old; tk_new = tkip_new; } return !crypto_memneq(tk_old, tk_new, new->conf.keylen); } int ieee80211_key_link(struct ieee80211_key *key, struct ieee80211_link_data *link, struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = link->sdata; static atomic_t key_color = ATOMIC_INIT(0); struct ieee80211_key *old_key = NULL; int idx = key->conf.keyidx; bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE; /* * We want to delay tailroom updates only for station - in that * case it helps roaming speed, but in other cases it hurts and * can cause warnings to appear. */ bool delay_tailroom = sdata->vif.type == NL80211_IFTYPE_STATION; int ret = -EOPNOTSUPP; mutex_lock(&sdata->local->key_mtx); if (sta && pairwise) { struct ieee80211_key *alt_key; old_key = key_mtx_dereference(sdata->local, sta->ptk[idx]); alt_key = key_mtx_dereference(sdata->local, sta->ptk[idx ^ 1]); /* The rekey code assumes that the old and new key are using * the same cipher. Enforce the assumption for pairwise keys. */ if ((alt_key && alt_key->conf.cipher != key->conf.cipher) || (old_key && old_key->conf.cipher != key->conf.cipher)) goto out; } else if (sta) { struct link_sta_info *link_sta = &sta->deflink; int link_id = key->conf.link_id; if (link_id >= 0) { link_sta = rcu_dereference_protected(sta->link[link_id], lockdep_is_held(&sta->local->sta_mtx)); if (!link_sta) { ret = -ENOLINK; goto out; } } old_key = key_mtx_dereference(sdata->local, link_sta->gtk[idx]); } else { if (idx < NUM_DEFAULT_KEYS) old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]); if (!old_key) old_key = key_mtx_dereference(sdata->local, link->gtk[idx]); } /* Non-pairwise keys must also not switch the cipher on rekey */ if (!pairwise) { if (old_key && old_key->conf.cipher != key->conf.cipher) goto out; } /* * Silently accept key re-installation without really installing the * new version of the key to avoid nonce reuse or replay issues. */ if (ieee80211_key_identical(sdata, old_key, key)) { ieee80211_key_free_unused(key); ret = 0; goto out; } key->local = sdata->local; key->sdata = sdata; key->sta = sta; /* * Assign a unique ID to every key so we can easily prevent mixed * key and fragment cache attacks. */ key->color = atomic_inc_return(&key_color); increment_tailroom_need_count(sdata); ret = ieee80211_key_replace(sdata, link, sta, pairwise, old_key, key); if (!ret) { ieee80211_debugfs_key_add(key); ieee80211_key_destroy(old_key, delay_tailroom); } else { ieee80211_key_free(key, delay_tailroom); } out: mutex_unlock(&sdata->local->key_mtx); return ret; } void ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom) { if (!key) return; /* * Replace key with nothingness if it was ever used. */ if (key->sdata) ieee80211_key_replace(key->sdata, NULL, key->sta, key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, key, NULL); ieee80211_key_destroy(key, delay_tailroom); } void ieee80211_reenable_keys(struct ieee80211_sub_if_data *sdata) { struct ieee80211_key *key; struct ieee80211_sub_if_data *vlan; lockdep_assert_wiphy(sdata->local->hw.wiphy); mutex_lock(&sdata->local->key_mtx); sdata->crypto_tx_tailroom_needed_cnt = 0; sdata->crypto_tx_tailroom_pending_dec = 0; if (sdata->vif.type == NL80211_IFTYPE_AP) { list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) { vlan->crypto_tx_tailroom_needed_cnt = 0; vlan->crypto_tx_tailroom_pending_dec = 0; } } if (ieee80211_sdata_running(sdata)) { list_for_each_entry(key, &sdata->key_list, list) { increment_tailroom_need_count(sdata); ieee80211_key_enable_hw_accel(key); } } mutex_unlock(&sdata->local->key_mtx); } void ieee80211_iter_keys(struct ieee80211_hw *hw, struct ieee80211_vif *vif, void (*iter)(struct ieee80211_hw *hw, struct ieee80211_vif *vif, struct ieee80211_sta *sta, struct ieee80211_key_conf *key, void *data), void *iter_data) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_key *key, *tmp; struct ieee80211_sub_if_data *sdata; lockdep_assert_wiphy(hw->wiphy); mutex_lock(&local->key_mtx); if (vif) { sdata = vif_to_sdata(vif); list_for_each_entry_safe(key, tmp, &sdata->key_list, list) iter(hw, &sdata->vif, key->sta ? &key->sta->sta : NULL, &key->conf, iter_data); } else { list_for_each_entry(sdata, &local->interfaces, list) list_for_each_entry_safe(key, tmp, &sdata->key_list, list) iter(hw, &sdata->vif, key->sta ? &key->sta->sta : NULL, &key->conf, iter_data); } mutex_unlock(&local->key_mtx); } EXPORT_SYMBOL(ieee80211_iter_keys); static void _ieee80211_iter_keys_rcu(struct ieee80211_hw *hw, struct ieee80211_sub_if_data *sdata, void (*iter)(struct ieee80211_hw *hw, struct ieee80211_vif *vif, struct ieee80211_sta *sta, struct ieee80211_key_conf *key, void *data), void *iter_data) { struct ieee80211_key *key; list_for_each_entry_rcu(key, &sdata->key_list, list) { /* skip keys of station in removal process */ if (key->sta && key->sta->removed) continue; if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) continue; iter(hw, &sdata->vif, key->sta ? &key->sta->sta : NULL, &key->conf, iter_data); } } void ieee80211_iter_keys_rcu(struct ieee80211_hw *hw, struct ieee80211_vif *vif, void (*iter)(struct ieee80211_hw *hw, struct ieee80211_vif *vif, struct ieee80211_sta *sta, struct ieee80211_key_conf *key, void *data), void *iter_data) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_sub_if_data *sdata; if (vif) { sdata = vif_to_sdata(vif); _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data); } else { list_for_each_entry_rcu(sdata, &local->interfaces, list) _ieee80211_iter_keys_rcu(hw, sdata, iter, iter_data); } } EXPORT_SYMBOL(ieee80211_iter_keys_rcu); static void ieee80211_free_keys_iface(struct ieee80211_sub_if_data *sdata, struct list_head *keys) { struct ieee80211_key *key, *tmp; decrease_tailroom_need_count(sdata, sdata->crypto_tx_tailroom_pending_dec); sdata->crypto_tx_tailroom_pending_dec = 0; ieee80211_debugfs_key_remove_mgmt_default(sdata); ieee80211_debugfs_key_remove_beacon_default(sdata); list_for_each_entry_safe(key, tmp, &sdata->key_list, list) { ieee80211_key_replace(key->sdata, NULL, key->sta, key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, key, NULL); list_add_tail(&key->list, keys); } ieee80211_debugfs_key_update_default(sdata); } void ieee80211_remove_link_keys(struct ieee80211_link_data *link, struct list_head *keys) { struct ieee80211_sub_if_data *sdata = link->sdata; struct ieee80211_local *local = sdata->local; struct ieee80211_key *key, *tmp; mutex_lock(&local->key_mtx); list_for_each_entry_safe(key, tmp, &sdata->key_list, list) { if (key->conf.link_id != link->link_id) continue; ieee80211_key_replace(key->sdata, link, key->sta, key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, key, NULL); list_add_tail(&key->list, keys); } mutex_unlock(&local->key_mtx); } void ieee80211_free_key_list(struct ieee80211_local *local, struct list_head *keys) { struct ieee80211_key *key, *tmp; mutex_lock(&local->key_mtx); list_for_each_entry_safe(key, tmp, keys, list) __ieee80211_key_destroy(key, false); mutex_unlock(&local->key_mtx); } void ieee80211_free_keys(struct ieee80211_sub_if_data *sdata, bool force_synchronize) { struct ieee80211_local *local = sdata->local; struct ieee80211_sub_if_data *vlan; struct ieee80211_sub_if_data *master; struct ieee80211_key *key, *tmp; LIST_HEAD(keys); cancel_delayed_work_sync(&sdata->dec_tailroom_needed_wk); mutex_lock(&local->key_mtx); ieee80211_free_keys_iface(sdata, &keys); if (sdata->vif.type == NL80211_IFTYPE_AP) { list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) ieee80211_free_keys_iface(vlan, &keys); } if (!list_empty(&keys) || force_synchronize) synchronize_net(); list_for_each_entry_safe(key, tmp, &keys, list) __ieee80211_key_destroy(key, false); if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) { if (sdata->bss) { master = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt != master->crypto_tx_tailroom_needed_cnt); } } else { WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt || sdata->crypto_tx_tailroom_pending_dec); } if (sdata->vif.type == NL80211_IFTYPE_AP) { list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) WARN_ON_ONCE(vlan->crypto_tx_tailroom_needed_cnt || vlan->crypto_tx_tailroom_pending_dec); } mutex_unlock(&local->key_mtx); } void ieee80211_free_sta_keys(struct ieee80211_local *local, struct sta_info *sta) { struct ieee80211_key *key; int i; mutex_lock(&local->key_mtx); for (i = 0; i < ARRAY_SIZE(sta->deflink.gtk); i++) { key = key_mtx_dereference(local, sta->deflink.gtk[i]); if (!key) continue; ieee80211_key_replace(key->sdata, NULL, key->sta, key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, key, NULL); __ieee80211_key_destroy(key, key->sdata->vif.type == NL80211_IFTYPE_STATION); } for (i = 0; i < NUM_DEFAULT_KEYS; i++) { key = key_mtx_dereference(local, sta->ptk[i]); if (!key) continue; ieee80211_key_replace(key->sdata, NULL, key->sta, key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE, key, NULL); __ieee80211_key_destroy(key, key->sdata->vif.type == NL80211_IFTYPE_STATION); } mutex_unlock(&local->key_mtx); } void ieee80211_delayed_tailroom_dec(struct work_struct *wk) { struct ieee80211_sub_if_data *sdata; sdata = container_of(wk, struct ieee80211_sub_if_data, dec_tailroom_needed_wk.work); /* * The reason for the delayed tailroom needed decrementing is to * make roaming faster: during roaming, all keys are first deleted * and then new keys are installed. The first new key causes the * crypto_tx_tailroom_needed_cnt to go from 0 to 1, which invokes * the cost of synchronize_net() (which can be slow). Avoid this * by deferring the crypto_tx_tailroom_needed_cnt decrementing on * key removal for a while, so if we roam the value is larger than * zero and no 0->1 transition happens. * * The cost is that if the AP switching was from an AP with keys * to one without, we still allocate tailroom while it would no * longer be needed. However, in the typical (fast) roaming case * within an ESS this usually won't happen. */ mutex_lock(&sdata->local->key_mtx); decrease_tailroom_need_count(sdata, sdata->crypto_tx_tailroom_pending_dec); sdata->crypto_tx_tailroom_pending_dec = 0; mutex_unlock(&sdata->local->key_mtx); } void ieee80211_gtk_rekey_notify(struct ieee80211_vif *vif, const u8 *bssid, const u8 *replay_ctr, gfp_t gfp) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); trace_api_gtk_rekey_notify(sdata, bssid, replay_ctr); cfg80211_gtk_rekey_notify(sdata->dev, bssid, replay_ctr, gfp); } EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_notify); void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf, int tid, struct ieee80211_key_seq *seq) { struct ieee80211_key *key; const u8 *pn; key = container_of(keyconf, struct ieee80211_key, conf); switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_TKIP: if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS)) return; seq->tkip.iv32 = key->u.tkip.rx[tid].iv32; seq->tkip.iv16 = key->u.tkip.rx[tid].iv16; break; case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS)) return; if (tid < 0) pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS]; else pn = key->u.ccmp.rx_pn[tid]; memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN); break; case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_cmac.rx_pn; memcpy(seq->aes_cmac.pn, pn, IEEE80211_CMAC_PN_LEN); break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_gmac.rx_pn; memcpy(seq->aes_gmac.pn, pn, IEEE80211_GMAC_PN_LEN); break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS)) return; if (tid < 0) pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS]; else pn = key->u.gcmp.rx_pn[tid]; memcpy(seq->gcmp.pn, pn, IEEE80211_GCMP_PN_LEN); break; } } EXPORT_SYMBOL(ieee80211_get_key_rx_seq); void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf, int tid, struct ieee80211_key_seq *seq) { struct ieee80211_key *key; u8 *pn; key = container_of(keyconf, struct ieee80211_key, conf); switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_TKIP: if (WARN_ON(tid < 0 || tid >= IEEE80211_NUM_TIDS)) return; key->u.tkip.rx[tid].iv32 = seq->tkip.iv32; key->u.tkip.rx[tid].iv16 = seq->tkip.iv16; break; case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS)) return; if (tid < 0) pn = key->u.ccmp.rx_pn[IEEE80211_NUM_TIDS]; else pn = key->u.ccmp.rx_pn[tid]; memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN); break; case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_cmac.rx_pn; memcpy(pn, seq->aes_cmac.pn, IEEE80211_CMAC_PN_LEN); break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_gmac.rx_pn; memcpy(pn, seq->aes_gmac.pn, IEEE80211_GMAC_PN_LEN); break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: if (WARN_ON(tid < -1 || tid >= IEEE80211_NUM_TIDS)) return; if (tid < 0) pn = key->u.gcmp.rx_pn[IEEE80211_NUM_TIDS]; else pn = key->u.gcmp.rx_pn[tid]; memcpy(pn, seq->gcmp.pn, IEEE80211_GCMP_PN_LEN); break; default: WARN_ON(1); break; } } EXPORT_SYMBOL_GPL(ieee80211_set_key_rx_seq); void ieee80211_remove_key(struct ieee80211_key_conf *keyconf) { struct ieee80211_key *key; key = container_of(keyconf, struct ieee80211_key, conf); assert_key_lock(key->local); /* * if key was uploaded, we assume the driver will/has remove(d) * it, so adjust bookkeeping accordingly */ if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; if (!(key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC | IEEE80211_KEY_FLAG_PUT_MIC_SPACE | IEEE80211_KEY_FLAG_RESERVE_TAILROOM))) increment_tailroom_need_count(key->sdata); } ieee80211_key_free(key, false); } EXPORT_SYMBOL_GPL(ieee80211_remove_key); struct ieee80211_key_conf * ieee80211_gtk_rekey_add(struct ieee80211_vif *vif, struct ieee80211_key_conf *keyconf) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct ieee80211_key *key; int err; if (WARN_ON(!local->wowlan)) return ERR_PTR(-EINVAL); if (WARN_ON(vif->type != NL80211_IFTYPE_STATION)) return ERR_PTR(-EINVAL); key = ieee80211_key_alloc(keyconf->cipher, keyconf->keyidx, keyconf->keylen, keyconf->key, 0, NULL); if (IS_ERR(key)) return ERR_CAST(key); if (sdata->u.mgd.mfp != IEEE80211_MFP_DISABLED) key->conf.flags |= IEEE80211_KEY_FLAG_RX_MGMT; /* FIXME: this function needs to get a link ID */ err = ieee80211_key_link(key, &sdata->deflink, NULL); if (err) return ERR_PTR(err); return &key->conf; } EXPORT_SYMBOL_GPL(ieee80211_gtk_rekey_add); void ieee80211_key_mic_failure(struct ieee80211_key_conf *keyconf) { struct ieee80211_key *key; key = container_of(keyconf, struct ieee80211_key, conf); switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: key->u.aes_cmac.icverrors++; break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: key->u.aes_gmac.icverrors++; break; default: /* ignore the others for now, we don't keep counters now */ break; } } EXPORT_SYMBOL_GPL(ieee80211_key_mic_failure); void ieee80211_key_replay(struct ieee80211_key_conf *keyconf) { struct ieee80211_key *key; key = container_of(keyconf, struct ieee80211_key, conf); switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: key->u.ccmp.replays++; break; case WLAN_CIPHER_SUITE_AES_CMAC: case WLAN_CIPHER_SUITE_BIP_CMAC_256: key->u.aes_cmac.replays++; break; case WLAN_CIPHER_SUITE_BIP_GMAC_128: case WLAN_CIPHER_SUITE_BIP_GMAC_256: key->u.aes_gmac.replays++; break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: key->u.gcmp.replays++; break; } } EXPORT_SYMBOL_GPL(ieee80211_key_replay);