diff options
Diffstat (limited to 'net/mac80211/key.c')
| -rw-r--r-- | net/mac80211/key.c | 54 |
1 files changed, 50 insertions, 4 deletions
diff --git a/net/mac80211/key.c b/net/mac80211/key.c index a98fc2b5e0dc..938049395f90 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -4,7 +4,7 @@ * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> * Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net> * Copyright 2013-2014 Intel Mobile Communications GmbH - * Copyright 2015 Intel Deutschland GmbH + * Copyright 2015-2017 Intel Deutschland GmbH * * 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 @@ -19,6 +19,7 @@ #include <linux/slab.h> #include <linux/export.h> #include <net/mac80211.h> +#include <crypto/algapi.h> #include <asm/unaligned.h> #include "ieee80211_i.h" #include "driver-ops.h" @@ -609,6 +610,39 @@ void ieee80211_key_free_unused(struct ieee80211_key *key) 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_sub_if_data *sdata, struct sta_info *sta) @@ -620,9 +654,6 @@ int ieee80211_key_link(struct ieee80211_key *key, pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE; idx = key->conf.keyidx; - key->local = sdata->local; - key->sdata = sdata; - key->sta = sta; mutex_lock(&sdata->local->key_mtx); @@ -633,6 +664,20 @@ int ieee80211_key_link(struct ieee80211_key *key, else old_key = key_mtx_dereference(sdata->local, sdata->keys[idx]); + /* + * 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; + increment_tailroom_need_count(sdata); ieee80211_key_replace(sdata, sta, pairwise, old_key, key); @@ -648,6 +693,7 @@ int ieee80211_key_link(struct ieee80211_key *key, ret = 0; } + out: mutex_unlock(&sdata->local->key_mtx); return ret; |